gtk-demo: Add a few path benchmarks

The Tiger and Graph examples in the fishbowl test
path handling.

.gitlab-ci/test-msys2.sh

@@ -15,9 +15,9 @@ pacman --noconfirm -Suy
 pacman --noconfirm -S --needed \
     base-devel \
     git \
-    mingw-w64-$MSYS2_ARCH-toolchain \
+    mingw-w64-$MSYS2_ARCH-cc \
     mingw-w64-$MSYS2_ARCH-ccache \
-    mingw-w64-$MSYS2_ARCH-pkg-config \
+    mingw-w64-$MSYS2_ARCH-pkgconf \
     mingw-w64-$MSYS2_ARCH-gobject-introspection \
     mingw-w64-$MSYS2_ARCH-meson \
     mingw-w64-$MSYS2_ARCH-adwaita-icon-theme \
@@ -30,7 +30,7 @@ pacman --noconfirm -S --needed \
     mingw-w64-$MSYS2_ARCH-libepoxy \
     mingw-w64-$MSYS2_ARCH-pango \
     mingw-w64-$MSYS2_ARCH-fribidi \
-    mingw-w64-$MSYS2_ARCH-gst-plugins-bad \
+    mingw-w64-$MSYS2_ARCH-gst-plugins-bad-libs \
     mingw-w64-$MSYS2_ARCH-shared-mime-info \
     mingw-w64-$MSYS2_ARCH-python-gobject
 

demos/gtk-demo/cursors.c

@@ -24,6 +24,7 @@ do_cursors (GtkWidget *do_widget)
 
       builder = gtk_builder_new_from_resource ("/cursors/cursors.ui");
       window = GTK_WIDGET (gtk_builder_get_object (builder, "window"));
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
       gtk_window_set_display (GTK_WINDOW (window),
                               gtk_widget_get_display (do_widget));
       g_signal_connect (window, "destroy",
@@ -34,9 +35,7 @@ do_cursors (GtkWidget *do_widget)
   if (!gtk_widget_get_visible (window))
     gtk_widget_show (window);
   else
-    {
-      gtk_window_destroy (GTK_WINDOW (window));
-    }
+    gtk_window_destroy (GTK_WINDOW (window));
 
   return window;
 }

demos/gtk-demo/curve-editor.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+#define CURVE_TYPE_EDITOR (curve_editor_get_type ())
+G_DECLARE_FINAL_TYPE (CurveEditor, curve_editor, CURVE, EDITOR, GtkWidget)
+
+GtkWidget *       curve_editor_new              (void);
+
+void              curve_editor_set_edit         (CurveEditor *self,
+                                                 gboolean     edit);
+
+void              curve_editor_set_path         (CurveEditor *self,
+                                                 GskPath     *path);
+
+GskPath *         curve_editor_get_path         (CurveEditor *self);
+
+void              curve_editor_set_stroke       (CurveEditor *self,
+                                                 GskStroke   *stroke);
+
+const GskStroke * curve_editor_get_stroke       (CurveEditor *self);
+
+
+void              curve_editor_set_color        (CurveEditor *self,
+                                                 GdkRGBA     *color);
+
+const GdkRGBA *   curve_editor_get_color        (CurveEditor *self);
+
+gboolean          curve_editor_get_show_outline (CurveEditor *self);
+
+void              curve_editor_set_show_outline (CurveEditor *self,
+                                                 gboolean     show_outline);
+
+G_END_DECLS

demos/gtk-demo/curve.c

@@ -0,0 +1,272 @@
+/* Path/Curve Editor
+ *
+ * This demo shows an elaborate curve editor that you would expect to find
+ * in a vector graphics editor. It is built on top of GTK's path APIs.
+ */
+
+#include <gtk/gtk.h>
+#include "curve-editor.h"
+
+
+static GskPath *
+make_circle_path (void)
+{
+  float w = 310;
+  float h = 310;
+  float cx = w / 2;
+  float cy = h / 2;
+  float pad = 20;
+  float r = (w - 2 * pad) / 2;
+  float k = 0.55228;
+  float kr = k  * r;
+  GskPathBuilder *builder;
+
+  builder = gsk_path_builder_new ();
+
+  gsk_path_builder_move_to (builder,  cx, pad);
+  gsk_path_builder_curve_to (builder, cx + kr, pad,
+                                      w - pad, cy - kr,
+                                      w - pad, cy);
+  gsk_path_builder_curve_to (builder, w - pad, cy + kr,
+                                      cx + kr, h - pad,
+                                      cx, h - pad);
+  gsk_path_builder_curve_to (builder, cx - kr, h - pad,
+                                      pad, cy + kr,
+                                      pad, cy);
+  gsk_path_builder_curve_to (builder, pad, cy - kr,
+                                      cx - kr, pad,
+                                      cx, pad);
+  gsk_path_builder_close (builder);
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+static void
+edit_changed (GtkToggleButton *button,
+              GParamSpec      *pspec,
+              CurveEditor     *editor)
+{
+  curve_editor_set_edit (editor, gtk_toggle_button_get_active (button));
+}
+
+static void
+reset (GtkButton   *button,
+       CurveEditor *editor)
+{
+  GskPath *path;
+
+  path = make_circle_path ();
+  curve_editor_set_path (editor, path);
+  gsk_path_unref (path);
+}
+
+static void
+line_width_changed (GtkSpinButton *spin,
+                    CurveEditor   *editor)
+{
+  GskStroke *stroke;
+
+  stroke = gsk_stroke_copy (curve_editor_get_stroke (editor));
+  gsk_stroke_set_line_width (stroke, gtk_spin_button_get_value (spin));
+  curve_editor_set_stroke (editor, stroke);
+  gsk_stroke_free (stroke);
+}
+
+static void
+cap_changed (GtkDropDown *combo,
+             GParamSpec  *pspec,
+             CurveEditor *editor)
+{
+  GskStroke *stroke;
+
+  stroke = gsk_stroke_copy (curve_editor_get_stroke (editor));
+  gsk_stroke_set_line_cap (stroke, (GskLineCap)gtk_drop_down_get_selected (combo));
+  curve_editor_set_stroke (editor, stroke);
+  gsk_stroke_free (stroke);
+}
+
+static void
+join_changed (GtkDropDown *combo,
+              GParamSpec  *pspec,
+              CurveEditor *editor)
+{
+  GskStroke *stroke;
+
+  stroke = gsk_stroke_copy (curve_editor_get_stroke (editor));
+  gsk_stroke_set_line_join (stroke, (GskLineJoin)gtk_drop_down_get_selected (combo));
+  curve_editor_set_stroke (editor, stroke);
+  gsk_stroke_free (stroke);
+}
+
+static void
+color_changed (GtkColorChooser *chooser,
+               GParamSpec      *pspec,
+               CurveEditor     *editor)
+{
+  GdkRGBA color;
+
+  gtk_color_chooser_get_rgba (chooser, &color);
+  curve_editor_set_color (editor, &color);
+}
+
+static void
+stroke_toggled (GtkCheckButton *button,
+                CurveEditor    *editor)
+{
+  curve_editor_set_show_outline (editor, gtk_check_button_get_active (button));
+  gtk_widget_queue_draw (GTK_WIDGET (editor));
+}
+
+static void
+limit_changed (GtkSpinButton *spin,
+               CurveEditor   *editor)
+{
+  GskStroke *stroke;
+
+  stroke = gsk_stroke_copy (curve_editor_get_stroke (editor));
+  gsk_stroke_set_miter_limit (stroke, gtk_spin_button_get_value (spin));
+  curve_editor_set_stroke (editor, stroke);
+  gsk_stroke_free (stroke);
+}
+
+static void
+dashes_changed (GtkEntry    *entry,
+                GParamSpec  *spec,
+                CurveEditor *editor)
+{
+  const char *text;
+  char **split;
+  GArray *dash;
+  GskStroke *stroke;
+
+  text = gtk_editable_get_text (GTK_EDITABLE (entry));
+  split = g_strsplit (text, " ", 0);
+
+  dash = g_array_new (FALSE, FALSE, sizeof (float));
+  for (int i = 0; split[i] != NULL; i++)
+    {
+      double d;
+      char *endp = 0;
+
+      d = g_strtod (split[i], &endp);
+      if (*endp == '\0')
+        g_array_append_vals (dash, (float[1]) { d }, 1);
+    }
+
+  g_strfreev (split);
+
+  stroke = gsk_stroke_copy (curve_editor_get_stroke (editor));
+  gsk_stroke_set_dash (stroke, (const float *)dash->data, dash->len);
+  curve_editor_set_stroke (editor, stroke);
+  gsk_stroke_free (stroke);
+
+  g_array_free (dash, TRUE);
+}
+
+GtkWidget *
+do_curve (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+  GtkWidget *demo;
+  GtkWidget *edit_toggle;
+  GtkWidget *reset_button;
+  GtkWidget *titlebar;
+  GtkWidget *stroke_toggle;
+  GtkWidget *line_width_spin;
+  GtkWidget *stroke_button;
+  GtkWidget *popover;
+  GtkWidget *grid;
+  GtkWidget *cap_combo;
+  GtkWidget *join_combo;
+  GtkWidget *color_button;
+  GtkWidget *limit_spin;
+  GtkWidget *dash_entry;
+
+  if (!window)
+    {
+      window = gtk_window_new ();
+      gtk_window_set_title (GTK_WINDOW (window), "Curve Editor");
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
+      gtk_window_set_default_size (GTK_WINDOW (window), 315, 350);
+
+      edit_toggle = gtk_toggle_button_new ();
+      gtk_button_set_icon_name (GTK_BUTTON (edit_toggle), "document-edit-symbolic");
+
+      reset_button = gtk_button_new_from_icon_name ("edit-undo-symbolic");
+
+      stroke_button = gtk_menu_button_new ();
+      gtk_menu_button_set_icon_name (GTK_MENU_BUTTON (stroke_button), "open-menu-symbolic");
+      popover = gtk_popover_new ();
+      gtk_menu_button_set_popover (GTK_MENU_BUTTON (stroke_button), popover);
+
+      grid = gtk_grid_new ();
+      gtk_grid_set_row_spacing (GTK_GRID (grid), 6);
+      gtk_grid_set_column_spacing (GTK_GRID (grid), 6);
+      gtk_popover_set_child (GTK_POPOVER (popover), grid);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Color:"), 0, 0, 1, 1);
+      color_button = gtk_color_button_new_with_rgba (&(GdkRGBA){ 0., 0., 0., 1.});
+      gtk_grid_attach (GTK_GRID (grid), color_button, 1, 0, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Line width:"), 0, 1, 1, 1);
+      line_width_spin = gtk_spin_button_new_with_range (1, 20, 1);
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (line_width_spin), 1);
+      gtk_grid_attach (GTK_GRID (grid), line_width_spin, 1, 1, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Line cap:"), 0, 2, 1, 1);
+      cap_combo = gtk_drop_down_new_from_strings ((const char *[]){"Butt", "Round", "Square", NULL});
+      gtk_grid_attach (GTK_GRID (grid), cap_combo, 1, 2, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Line join:"), 0, 3, 1, 1);
+      join_combo = gtk_drop_down_new_from_strings ((const char *[]){"Miter", "Miter-clip", "Round", "Bevel", "Arcs", NULL});
+      gtk_grid_attach (GTK_GRID (grid), join_combo, 1, 3, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Miter limit:"), 0, 4, 1, 1);
+      limit_spin = gtk_spin_button_new_with_range (0, 10, 1);
+      gtk_spin_button_set_digits (GTK_SPIN_BUTTON (limit_spin), 1);
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (limit_spin), 4);
+      gtk_grid_attach (GTK_GRID (grid), limit_spin, 1, 4, 1, 1);
+
+      gtk_grid_attach (GTK_GRID (grid), gtk_label_new ("Dashes:"), 0, 5, 1, 1);
+      dash_entry = gtk_entry_new ();
+      gtk_grid_attach (GTK_GRID (grid), dash_entry, 1, 5, 1, 1);
+
+      stroke_toggle = gtk_check_button_new_with_label ("Show outline");
+      gtk_grid_attach (GTK_GRID (grid), stroke_toggle, 1, 6, 1, 1);
+
+      titlebar = gtk_header_bar_new ();
+      gtk_header_bar_pack_start (GTK_HEADER_BAR (titlebar), edit_toggle);
+      gtk_header_bar_pack_start (GTK_HEADER_BAR (titlebar), reset_button);
+      gtk_header_bar_pack_start (GTK_HEADER_BAR (titlebar), stroke_button);
+
+      gtk_window_set_titlebar (GTK_WINDOW (window), titlebar);
+
+      demo = curve_editor_new ();
+
+      g_signal_connect (stroke_toggle, "toggled", G_CALLBACK (stroke_toggled), demo);
+      g_signal_connect (edit_toggle, "notify::active", G_CALLBACK (edit_changed), demo);
+      g_signal_connect (reset_button, "clicked", G_CALLBACK (reset), demo);
+      g_signal_connect (cap_combo, "notify::selected", G_CALLBACK (cap_changed), demo);
+      g_signal_connect (join_combo, "notify::selected", G_CALLBACK (join_changed), demo);
+      g_signal_connect (color_button, "notify::rgba", G_CALLBACK (color_changed), demo);
+      g_signal_connect (line_width_spin, "value-changed", G_CALLBACK (line_width_changed), demo);
+      g_signal_connect (limit_spin, "value-changed", G_CALLBACK (limit_changed), demo);
+      g_signal_connect (dash_entry, "notify::text", G_CALLBACK (dashes_changed), demo);
+
+      reset (NULL, CURVE_EDITOR (demo));
+
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (line_width_spin), 6);
+      gtk_color_chooser_set_rgba (GTK_COLOR_CHOOSER (color_button), &(GdkRGBA) { 1, 0, 0, 1 });
+      gtk_drop_down_set_selected (GTK_DROP_DOWN (cap_combo), GSK_LINE_CAP_ROUND);
+      gtk_editable_set_text (GTK_EDITABLE (dash_entry), "0 8");
+
+      gtk_window_set_child (GTK_WINDOW (window), demo);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_window_destroy (GTK_WINDOW (window));
+
+  return window;
+}

demos/gtk-demo/demo.gresource.xml

@@ -128,6 +128,7 @@
     <file>fishbowl.ui</file>
     <file>gtkfishbowl.c</file>
     <file>gtkfishbowl.h</file>
+    <file>tiger.node</file>
   </gresource>
   <gresource prefix="/frames">
     <file>frames.ui</file>
@@ -250,6 +251,10 @@
   <gresource prefix="/video-player">
     <file>bbb.png</file>
   </gresource>
+  <gresource prefix="/curve">
+    <file>curve-editor.c</file>
+    <file>curve-editor.h</file>
+  </gresource>
   <gresource prefix="/sources">
     <file>application_demo.c</file>
     <file>assistant.c</file>
@@ -267,6 +272,7 @@
     <file>css_pixbufs.c</file>
     <file>css_shadows.c</file>
     <file>cursors.c</file>
+    <file>curve.c</file>
     <file>dialog.c</file>
     <file>drawingarea.c</file>
     <file>dropdown.c</file>
@@ -287,6 +293,7 @@
     <file>gears.c</file>
     <file>gestures.c</file>
     <file>glarea.c</file>
+    <file>glyphs.c</file>
     <file>gltransition.c</file>
     <file>headerbar.c</file>
     <file>hypertext.c</file>
@@ -325,6 +332,9 @@
     <file>paintable_symbolic.c</file>
     <file>panes.c</file>
     <file>password_entry.c</file>
+    <file>path_fill.c</file>
+    <file>path_maze.c</file>
+    <file>path_text.c</file>
     <file>peg_solitaire.c</file>
     <file>pickers.c</file>
     <file>printing.c</file>
@@ -409,6 +419,9 @@
   <gresource prefix="/fontrendering">
     <file>fontrendering.ui</file>
   </gresource>
+  <gresource prefix="/path_text">
+    <file>path_text.ui</file>
+  </gresource>
   <gresource prefix="/org/gtk/Demo4">
     <file>icons/16x16/actions/application-exit.png</file>
     <file>icons/16x16/actions/document-new.png</file>

demos/gtk-demo/fishbowl.c

@@ -11,6 +11,9 @@
 #include "gtkgears.h"
 #include "gskshaderpaintable.h"
 
+#include "nodewidget.h"
+#include "graphwidget.h"
+
 const char *const css =
 ".blurred-button {"
 "  box-shadow: 0px 0px 5px 10px rgba(0, 0, 0, 0.5);"
@@ -201,6 +204,18 @@ create_menu_button (void)
   return w;
 }
 
+static GtkWidget *
+create_tiger (void)
+{
+  return node_widget_new ("/fishbowl/tiger.node");
+}
+
+static GtkWidget *
+create_graph (void)
+{
+  return graph_widget_new ();
+}
+
 static const struct {
   const char *name;
   GtkWidget * (*create_func) (void);
@@ -218,6 +233,8 @@ static const struct {
   { "Switch",     create_switch         },
   { "Menubutton", create_menu_button    },
   { "Shader",     create_cogs           },
+  { "Tiger",      create_tiger          },
+  { "Graph",      create_graph          },
 };
 
 static int selected_widget_type = -1;

demos/gtk-demo/graphwidget.c

@@ -0,0 +1,164 @@
+#include "graphwidget.h"
+
+struct _GraphWidget
+{
+  GtkWidget parent_instance;
+
+  GskPath *path;
+  GskStroke *stroke;
+  GdkRGBA color;
+  GskPath *stroke_path;
+
+  guint tick_cb;
+  guint64 start_time;
+
+  double period;
+  double amplitude;
+};
+
+struct _GraphWidgetClass
+{
+  GtkWidgetClass parent_class;
+};
+
+G_DEFINE_TYPE (GraphWidget, graph_widget, GTK_TYPE_WIDGET)
+
+static void
+update_path (GraphWidget *self,
+             float        amplitude)
+{
+  graphene_point_t p[20];
+  GskPathBuilder *builder;
+
+  g_clear_pointer (&self->path, gsk_path_unref);
+  g_clear_pointer (&self->stroke_path, gsk_path_unref);
+
+  for (int i = 0; i < 20; i++)
+    {
+      p[i].x = 10 * i;
+      p[i].y = 50;
+
+      if (i % 4 == 1 || i % 4 == 2)
+        {
+          if (i % 8 < 4)
+            p[i].y += amplitude;
+          else
+            p[i].y -= amplitude;
+        }
+    }
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_move_to (builder, p[0].x, p[0].y);
+
+  for (int i = 0; i < 20; i += 4)
+    gsk_path_builder_curve_to (builder,
+                               p[i+1].x, p[i+1].y,
+                               p[i+2].x, p[i+2].y,
+                               p[i+3].x, p[i+3].y);
+
+  self->path = gsk_path_builder_free_to_path (builder);
+  self->stroke_path = gsk_path_stroke (self->path, self->stroke);
+}
+
+static gboolean
+tick_cb (GtkWidget     *widget,
+         GdkFrameClock *frame_clock,
+         gpointer       user_data)
+{
+  GraphWidget *self = GRAPH_WIDGET (widget);
+  guint64 now;
+  double angle;
+
+  now = gdk_frame_clock_get_frame_time (frame_clock);
+
+  if (self->start_time == 0)
+    self->start_time = now;
+
+  angle = 360 * (now - self->start_time) / (double)(self->period * G_TIME_SPAN_MINUTE);
+  update_path (self, sin (angle) * self->amplitude);
+
+  gtk_widget_queue_draw (widget);
+
+  return G_SOURCE_CONTINUE;
+}
+
+static void
+graph_widget_init (GraphWidget *self)
+{
+  self->color.red = g_random_double_range (0, 1);
+  self->color.green = g_random_double_range (0, 1);
+  self->color.blue = g_random_double_range (0, 1);
+  self->color.alpha = 1;
+
+  self->period = g_random_double_range (0.5, 1);
+  self->amplitude = g_random_double_range (10, 25);
+
+  self->stroke = gsk_stroke_new (2);
+
+  update_path (self, 0);
+
+  self->start_time = 0;
+  self->tick_cb = gtk_widget_add_tick_callback (GTK_WIDGET (self), tick_cb, NULL, NULL);
+}
+
+static void
+graph_widget_dispose (GObject *object)
+{
+  GraphWidget *self = GRAPH_WIDGET (object);
+
+  gsk_path_unref (self->path);
+  gsk_stroke_free (self->stroke);
+
+  G_OBJECT_CLASS (graph_widget_parent_class)->dispose (object);
+}
+
+static void
+graph_widget_snapshot (GtkWidget   *widget,
+                      GtkSnapshot *snapshot)
+{
+  GraphWidget *self = GRAPH_WIDGET (widget);
+  int width, height;
+
+  width = gtk_widget_get_width (widget);
+  height = gtk_widget_get_height (widget);
+
+  gtk_snapshot_push_fill (snapshot, self->stroke_path, GSK_FILL_RULE_WINDING);
+  gtk_snapshot_append_color (snapshot,
+                             &self->color,
+                             &GRAPHENE_RECT_INIT (0, 0, width, height));
+  gtk_snapshot_pop (snapshot);
+}
+
+static void
+graph_widget_measure (GtkWidget      *widget,
+                      GtkOrientation  orientation,
+                      int             for_size,
+                      int            *minimum,
+                      int            *natural,
+                      int            *minimum_baseline,
+                      int            *natural_baseline)
+{
+  if (orientation == GTK_ORIENTATION_HORIZONTAL)
+    *minimum = *natural = 200;
+  else
+    *minimum = *natural = 100;
+}
+
+
+static void
+graph_widget_class_init (GraphWidgetClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
+
+  object_class->dispose = graph_widget_dispose;
+
+  widget_class->snapshot = graph_widget_snapshot;
+  widget_class->measure = graph_widget_measure;
+}
+
+GtkWidget *
+graph_widget_new (void)
+{
+  return g_object_new (GRAPH_TYPE_WIDGET, NULL);
+}

demos/gtk-demo/graphwidget.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <gtk/gtk.h>
+
+#define GRAPH_TYPE_WIDGET (graph_widget_get_type ())
+G_DECLARE_FINAL_TYPE (GraphWidget, graph_widget, GRAPH, WIDGET, GtkWidget)
+
+GtkWidget * graph_widget_new       (void);

demos/gtk-demo/main.c

@@ -512,7 +512,7 @@ load_file (const char *demoname,
 
   info_buffer = gtk_text_buffer_new (NULL);
   gtk_text_buffer_create_tag (info_buffer, "title",
-                              "font", "Sans 18",
+                              "size", 18 * 1024,
                               "pixels-below-lines", 10,
                               NULL);
 

demos/gtk-demo/meson.build

@@ -17,6 +17,7 @@ demos = files([
   'css_pixbufs.c',
   'css_shadows.c',
   'cursors.c',
+  'curve.c',
   'dialog.c',
   'drawingarea.c',
   'dnd.c',
@@ -34,6 +35,7 @@ demos = files([
   'gestures.c',
   'glarea.c',
   'gltransition.c',
+  'glyphs.c',
   'headerbar.c',
   'hypertext.c',
   'iconscroll.c',
@@ -70,6 +72,9 @@ demos = files([
   'paintable_symbolic.c',
   'panes.c',
   'password_entry.c',
+  'path_fill.c',
+  'path_maze.c',
+  'path_text.c',
   'peg_solitaire.c',
   'pickers.c',
   'printing.c',
@@ -130,6 +135,9 @@ extra_demo_sources = files([
   'unicode-names.c',
   'suggestionentry.c',
   'language-names.c',
+  'curve-editor.c',
+  'nodewidget.c',
+  'graphwidget.c',
 ])
 
 if os_unix

demos/gtk-demo/nodewidget.c

@@ -0,0 +1,76 @@
+#include "nodewidget.h"
+
+struct _NodeWidget
+{
+  GtkWidget parent_instance;
+
+  GskRenderNode *node;
+};
+
+struct _NodeWidgetClass
+{
+  GtkWidgetClass parent_class;
+};
+
+G_DEFINE_TYPE (NodeWidget, node_widget, GTK_TYPE_WIDGET)
+
+static void
+node_widget_init (NodeWidget *self)
+{
+}
+
+static void
+node_widget_dispose (GObject *object)
+{
+  NodeWidget *self = NODE_WIDGET (object);
+
+  gsk_render_node_unref (self->node);
+
+  G_OBJECT_CLASS (node_widget_parent_class)->dispose (object);
+}
+
+static void
+node_widget_snapshot (GtkWidget   *widget,
+                      GtkSnapshot *snapshot)
+{
+  NodeWidget *self = NODE_WIDGET (widget);
+
+  gtk_snapshot_append_node (snapshot, self->node);
+}
+
+static void
+node_widget_class_init (NodeWidgetClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
+
+  object_class->dispose = node_widget_dispose;
+
+  widget_class->snapshot = node_widget_snapshot;
+}
+
+GtkWidget *
+node_widget_new (const char *resource)
+{
+  NodeWidget *self;
+  GBytes *bytes;
+  GskRenderNode *node;
+  graphene_rect_t bounds;
+  float scale;
+  GskTransform *transform;
+
+  self = g_object_new (NODE_TYPE_WIDGET, NULL);
+
+  bytes = g_resources_lookup_data (resource, 0, NULL);
+  node = gsk_render_node_deserialize (bytes, NULL, NULL);
+  g_bytes_unref (bytes);
+
+  gsk_render_node_get_bounds (node, &bounds);
+  scale = MIN (100.0/bounds.size.width, 100.0/bounds.size.height);
+  transform = gsk_transform_scale (NULL, scale, scale);
+  self->node = gsk_transform_node_new (node, transform);
+  gsk_transform_unref (transform);
+  gsk_render_node_unref (node);
+
+  return GTK_WIDGET (self);
+}

demos/gtk-demo/nodewidget.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <gtk/gtk.h>
+
+#define NODE_TYPE_WIDGET (node_widget_get_type ())
+G_DECLARE_FINAL_TYPE (NodeWidget, node_widget, NODE, WIDGET, GtkWidget)
+
+GtkWidget * node_widget_new       (const char *file);

demos/gtk-demo/path_fill.c

@@ -0,0 +1,348 @@
+/* Path/Text Fill
+ *
+ * This demo shows how to use PangoCairo to draw text with more than
+ * just a single color.
+ */
+
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+
+#include "paintable.h"
+#include "gsk/gskpathdashprivate.h"
+
+#define GTK_TYPE_PATH_PAINTABLE (gtk_path_paintable_get_type ())
+G_DECLARE_FINAL_TYPE (GtkPathPaintable, gtk_path_paintable, GTK, PATH_PAINTABLE, GObject)
+
+struct _GtkPathPaintable
+{
+  GObject parent_instance;
+
+  int width;
+  int height;
+  GskPath *path;
+  GdkPaintable *background;
+};
+
+struct _GtkPathPaintableClass
+{
+  GObjectClass parent_class;
+};
+
+static int
+gtk_path_paintable_get_intrinsic_width (GdkPaintable *paintable)
+{
+  GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
+
+  if (self->background)
+    return MAX (gdk_paintable_get_intrinsic_width (self->background), self->width);
+  else
+    return self->width;
+}
+
+static int
+gtk_path_paintable_get_intrinsic_height (GdkPaintable *paintable)
+{
+  GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
+
+  if (self->background)
+    return MAX (gdk_paintable_get_intrinsic_height (self->background), self->height);
+  else
+    return self->height;
+}
+
+static void
+gtk_path_paintable_snapshot (GdkPaintable *paintable,
+                             GdkSnapshot  *snapshot,
+                             double        width,
+                             double        height)
+{
+  GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
+
+#if 0
+  gtk_snapshot_push_fill (snapshot, self->path, GSK_FILL_RULE_WINDING);
+#else
+  GskStroke *stroke = gsk_stroke_new (2.0);
+  gtk_snapshot_push_stroke (snapshot, self->path, stroke);
+  gsk_stroke_free (stroke);
+#endif
+
+  if (self->background)
+    {
+      gdk_paintable_snapshot (self->background, snapshot, width, height);
+    }
+  else
+    {
+      gtk_snapshot_append_linear_gradient (snapshot,
+                                           &GRAPHENE_RECT_INIT (0, 0, width, height),
+                                           &GRAPHENE_POINT_INIT (0, 0),
+                                           &GRAPHENE_POINT_INIT (width, height),
+                                           (GskColorStop[8]) {
+                                             { 0.0, { 1.0, 0.0, 0.0, 1.0 } },
+                                             { 0.2, { 1.0, 0.0, 0.0, 1.0 } },
+                                             { 0.3, { 1.0, 1.0, 0.0, 1.0 } },
+                                             { 0.4, { 0.0, 1.0, 0.0, 1.0 } },
+                                             { 0.6, { 0.0, 1.0, 1.0, 1.0 } },
+                                             { 0.7, { 0.0, 0.0, 1.0, 1.0 } },
+                                             { 0.8, { 1.0, 0.0, 1.0, 1.0 } },
+                                             { 1.0, { 1.0, 0.0, 1.0, 1.0 } }
+                                           },
+                                           8);
+    }
+
+  gtk_snapshot_pop (snapshot);
+
+}
+
+static GdkPaintableFlags
+gtk_path_paintable_get_flags (GdkPaintable *paintable)
+{
+  GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
+
+  if (self->background)
+    return gdk_paintable_get_flags (self->background);
+  else
+    return GDK_PAINTABLE_STATIC_CONTENTS | GDK_PAINTABLE_STATIC_SIZE;
+}
+
+static void
+gtk_path_paintable_paintable_init (GdkPaintableInterface *iface)
+{
+  iface->get_intrinsic_width = gtk_path_paintable_get_intrinsic_width;
+  iface->get_intrinsic_height = gtk_path_paintable_get_intrinsic_height;
+  iface->snapshot = gtk_path_paintable_snapshot;
+  iface->get_flags = gtk_path_paintable_get_flags;
+}
+
+/* When defining the GType, we need to implement the GdkPaintable interface */
+G_DEFINE_TYPE_WITH_CODE (GtkPathPaintable, gtk_path_paintable, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (GDK_TYPE_PAINTABLE,
+                                                gtk_path_paintable_paintable_init))
+
+/* Here's the boilerplate for the GObject declaration.
+ * We don't need to do anything special here, because we keep no
+ * data of our own.
+ */
+static void
+gtk_path_paintable_class_init (GtkPathPaintableClass *klass)
+{
+}
+
+static void
+gtk_path_paintable_init (GtkPathPaintable *self)
+{
+}
+
+/* And finally, we add a simple constructor.
+ * It is declared in the header so that the other examples
+ * can use it.
+ */
+GdkPaintable *
+gtk_path_paintable_new (GskPath      *path,
+                        GdkPaintable *background,
+                        int           width,
+                        int           height)
+{
+  GtkPathPaintable *self;
+
+  self = g_object_new (GTK_TYPE_PATH_PAINTABLE, NULL);
+  self->path = path;
+  self->background = background;
+  if (self->background)
+    {
+      g_signal_connect_swapped (self->background, "invalidate-contents", G_CALLBACK (gdk_paintable_invalidate_contents), self);
+      g_signal_connect_swapped (self->background, "invalidate-size", G_CALLBACK (gdk_paintable_invalidate_size), self);
+    }
+  self->width = width;
+  self->height = height;
+
+  return GDK_PAINTABLE (self);
+}
+
+void
+gtk_path_paintable_set_path (GtkPathPaintable *self,
+                             GskPath          *path)
+{
+  g_clear_pointer (&self->path, gsk_path_unref);
+  self->path = gsk_path_ref (path);
+
+  gdk_paintable_invalidate_contents (GDK_PAINTABLE (self));
+}
+
+static GskPath *
+create_hexagon (GtkWidget *widget)
+{
+  GskPathBuilder *builder;
+
+  builder = gsk_path_builder_new ();
+
+  gsk_path_builder_move_to (builder, 120, 0);
+  gsk_path_builder_line_to (builder, 360, 0);
+  gsk_path_builder_line_to (builder, 480, 208);
+  gsk_path_builder_line_to (builder, 360, 416);
+  gsk_path_builder_line_to (builder, 120, 416);
+  gsk_path_builder_line_to (builder, 0, 208);
+  gsk_path_builder_close (builder);
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+static GskPath *
+create_path_from_text (GtkWidget *widget)
+{
+  PangoLayout *layout;
+  PangoFontDescription *desc;
+  GskPathBuilder *builder;
+
+  layout = gtk_widget_create_pango_layout (widget, "Pango power!\nPango power!\nPango power!");
+  desc = pango_font_description_from_string ("sans bold 36");
+  pango_layout_set_font_description (layout, desc);
+  pango_font_description_free (desc);
+
+  builder = gsk_path_builder_new ();
+
+  gsk_path_builder_add_layout (builder, layout);
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+static gboolean
+build_path (GskPathOperation        op,
+            const graphene_point_t *pts,
+            gsize                   n_pts,
+            float                   weight,
+            gpointer                user_data)
+{
+  GskPathBuilder *builder = user_data;
+
+  switch (op)
+  {
+    case GSK_PATH_MOVE:
+      gsk_path_builder_move_to (builder, pts[0].x, pts[0].y);
+      break;
+
+    case GSK_PATH_CLOSE:
+      gsk_path_builder_close (builder);
+      break;
+
+    case GSK_PATH_LINE:
+      gsk_path_builder_line_to (builder, pts[1].x, pts[1].y);
+      break;
+
+    case GSK_PATH_CURVE:
+      gsk_path_builder_curve_to (builder, pts[1].x, pts[1].y, pts[2].x, pts[2].y, pts[3].x, pts[3].y);
+      break;
+
+    case GSK_PATH_CONIC:
+      gsk_path_builder_conic_to (builder, pts[1].x, pts[1].y, pts[2].x, pts[2].y, weight);
+      break;
+
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+
+  return TRUE;
+}
+
+
+static gboolean
+update_path (GtkWidget     *widget,
+             GdkFrameClock *frame_clock,
+             gpointer       measure)
+{
+  float progress = gdk_frame_clock_get_frame_time (frame_clock) % (60 * G_USEC_PER_SEC) / (float) (30 * G_USEC_PER_SEC);
+  GskPathBuilder *builder;
+  GskPath *path;
+  graphene_point_t pos;
+  graphene_vec2_t tangent;
+  GskStroke *stroke;
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_segment (builder,
+                                measure,
+#if 1
+                                0.0, gsk_path_measure_get_length (measure));
+#else
+                                progress > 1 ? (progress - 1) * gsk_path_measure_get_length (measure) : 0.0,
+                                (progress < 1 ? progress : 1.0) * gsk_path_measure_get_length (measure));
+#endif
+
+  path = gsk_path_builder_free_to_path (builder);
+
+  stroke = gsk_stroke_new (1);
+  gsk_stroke_set_dash (stroke, (float[2]) { 10, 5 }, 2);
+  gsk_stroke_set_dash_offset (stroke, - (gdk_frame_clock_get_frame_time (frame_clock) % G_USEC_PER_SEC) * 15. / G_USEC_PER_SEC);
+  builder = gsk_path_builder_new ();
+  gsk_path_dash (path, stroke, 0.2, build_path, builder);
+  gsk_path_unref (path);
+
+  gsk_path_measure_get_point (measure,
+                              (progress > 1 ? (progress - 1) : progress) * gsk_path_measure_get_length (measure),
+                              &pos,
+                              &tangent);
+  gsk_path_builder_move_to (builder, pos.x + 5 * graphene_vec2_get_x (&tangent), pos.y + 5 * graphene_vec2_get_y (&tangent));
+  gsk_path_builder_line_to (builder, pos.x + 3 * graphene_vec2_get_y (&tangent), pos.y + 3 * graphene_vec2_get_x (&tangent));
+  gsk_path_builder_line_to (builder, pos.x - 3 * graphene_vec2_get_y (&tangent), pos.y - 3 * graphene_vec2_get_x (&tangent));
+  gsk_path_builder_close (builder);
+
+  path = gsk_path_builder_free_to_path (builder);
+
+  gtk_path_paintable_set_path (GTK_PATH_PAINTABLE (gtk_picture_get_paintable (GTK_PICTURE (widget))),
+                               path);
+  gsk_path_unref (path);
+
+  return G_SOURCE_CONTINUE;
+}
+
+GtkWidget *
+do_path_fill (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkWidget *picture;
+      GdkPaintable *paintable;
+      GtkMediaStream *stream;
+      GskPath *path;
+      graphene_rect_t bounds;
+      GskPathMeasure *measure;
+
+      window = gtk_window_new ();
+      gtk_window_set_resizable (GTK_WINDOW (window), TRUE);
+      gtk_window_set_title (GTK_WINDOW (window), "Path Fill");
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
+
+#if 0
+      stream = gtk_media_file_new_for_resource ("/images/gtk-logo.webm");
+#else
+      stream = gtk_nuclear_media_stream_new ();
+#endif
+      gtk_media_stream_play (stream);
+      gtk_media_stream_set_loop (stream, TRUE);
+
+      path = create_hexagon (window);
+      path = create_path_from_text (window);
+      gsk_path_get_bounds (path, &bounds);
+
+      paintable = gtk_path_paintable_new (path,
+                                          GDK_PAINTABLE (stream),
+                                          bounds.origin.x + bounds.size.width,
+                                          bounds.origin.y + bounds.size.height);
+      picture = gtk_picture_new_for_paintable (paintable);
+      measure = gsk_path_measure_new (path);
+      gtk_widget_add_tick_callback (picture, update_path, measure, (GDestroyNotify) gsk_path_measure_unref);
+      gtk_picture_set_keep_aspect_ratio (GTK_PICTURE (picture), FALSE);
+      gtk_picture_set_can_shrink (GTK_PICTURE (picture), FALSE);
+      g_object_unref (paintable);
+
+      gtk_window_set_child (GTK_WINDOW (window), picture);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_window_destroy (GTK_WINDOW (window));
+
+  return window;
+}

demos/gtk-demo/path_maze.c

@@ -0,0 +1,339 @@
+/* Path/Maze
+ * #Keywords: game, mouse
+ *
+ * This demo shows how to use a GskPath to create a maze and use
+ * gsk_path_measure_get_closest_point() to check the mouse stays
+ * on the path.
+ *
+ * It also shows off the performance of GskPath (or not) as this
+ * is a rather complex path.
+ */
+
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+
+#include "paintable.h"
+
+#define MAZE_GRID_SIZE 20
+#define MAZE_STROKE_SIZE_ACTIVE (MAZE_GRID_SIZE - 4)
+#define MAZE_STROKE_SIZE_INACTIVE (MAZE_GRID_SIZE - 12)
+#define MAZE_WIDTH 31
+#define MAZE_HEIGHT 21
+
+#define GTK_TYPE_MAZE (gtk_maze_get_type ())
+G_DECLARE_FINAL_TYPE (GtkMaze, gtk_maze, GTK, MAZE, GtkWidget)
+
+struct _GtkMaze
+{
+  GtkWidget parent_instance;
+
+  int width;
+  int height;
+  GskPath *path;
+  GskPathMeasure *measure;
+  GdkPaintable *background;
+
+  gboolean active;
+};
+
+struct _GtkMazeClass
+{
+  GtkWidgetClass parent_class;
+};
+
+G_DEFINE_TYPE (GtkMaze, gtk_maze, GTK_TYPE_WIDGET)
+
+static void
+gtk_maze_measure (GtkWidget      *widget,
+                  GtkOrientation  orientation,
+                  int             for_size,
+                  int            *minimum,
+                  int            *natural,
+                  int            *minimum_baseline,
+                  int            *natural_baseline)
+{
+  GtkMaze *self = GTK_MAZE (widget);
+
+  if (orientation == GTK_ORIENTATION_HORIZONTAL)
+    *minimum = *natural = self->width;
+  else
+    *minimum = *natural = self->height;
+}
+
+static void
+gtk_maze_snapshot (GtkWidget   *widget,
+                   GdkSnapshot *snapshot)
+{
+  GtkMaze *self = GTK_MAZE (widget);
+  double width = gtk_widget_get_width (widget);
+  double height = gtk_widget_get_height (widget);
+  GskStroke *stroke;
+
+  stroke = gsk_stroke_new (MAZE_STROKE_SIZE_INACTIVE);
+  if (self->active)
+    gsk_stroke_set_line_width (stroke, MAZE_STROKE_SIZE_ACTIVE);
+  gsk_stroke_set_line_join (stroke, GSK_LINE_JOIN_ROUND);
+  gsk_stroke_set_line_cap (stroke, GSK_LINE_CAP_ROUND);
+  gtk_snapshot_push_stroke (snapshot, self->path, stroke);
+  gsk_stroke_free (stroke);
+
+  if (self->background)
+    {
+      gdk_paintable_snapshot (self->background, snapshot, width, height);
+    }
+  else
+    {
+      gtk_snapshot_append_linear_gradient (snapshot,
+                                           &GRAPHENE_RECT_INIT (0, 0, width, height),
+                                           &GRAPHENE_POINT_INIT (0, 0),
+                                           &GRAPHENE_POINT_INIT (width, height),
+                                           (GskColorStop[8]) {
+                                             { 0.0, { 1.0, 0.0, 0.0, 1.0 } },
+                                             { 0.2, { 1.0, 0.0, 0.0, 1.0 } },
+                                             { 0.3, { 1.0, 1.0, 0.0, 1.0 } },
+                                             { 0.4, { 0.0, 1.0, 0.0, 1.0 } },
+                                             { 0.6, { 0.0, 1.0, 1.0, 1.0 } },
+                                             { 0.7, { 0.0, 0.0, 1.0, 1.0 } },
+                                             { 0.8, { 1.0, 0.0, 1.0, 1.0 } },
+                                             { 1.0, { 1.0, 0.0, 1.0, 1.0 } }
+                                           },
+                                           8);
+    }
+
+  gtk_snapshot_pop (snapshot);
+
+}
+
+static void
+gtk_maze_dispose (GObject *object)
+{
+  GtkMaze *self = GTK_MAZE (object);
+
+  g_clear_pointer (&self->path, gsk_path_unref);
+  g_clear_pointer (&self->measure, gsk_path_measure_unref);
+  if (self->background)
+    {
+      g_signal_handlers_disconnect_matched (self->background, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
+      g_clear_object (&self->background);
+    }
+
+  G_OBJECT_CLASS (gtk_maze_parent_class)->dispose (object);
+}
+
+static void
+gtk_maze_class_init (GtkMazeClass *klass)
+{
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->dispose = gtk_maze_dispose;
+
+  widget_class->measure = gtk_maze_measure;
+  widget_class->snapshot = gtk_maze_snapshot;
+}
+
+static void
+pointer_motion (GtkEventControllerMotion *controller,
+                double                    x,
+                double                    y,
+                GtkMaze                  *self)
+{
+  if (!self->active)
+    return;
+
+  if (gsk_path_measure_get_closest_point (self->measure, &GRAPHENE_POINT_INIT (x, y), NULL) <= MAZE_STROKE_SIZE_ACTIVE / 2.0f)
+    return;
+
+  self->active = FALSE;
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+pointer_leave (GtkEventControllerMotion *controller,
+               GtkMaze                  *self)
+{
+  if (!self->active)
+    {
+      self->active = TRUE;
+      gtk_widget_queue_draw (GTK_WIDGET (self));
+    }
+}
+
+static void
+gtk_maze_init (GtkMaze *self)
+{
+  GtkEventController *controller;
+
+  controller = GTK_EVENT_CONTROLLER (gtk_event_controller_motion_new ());
+  g_signal_connect (controller, "motion", G_CALLBACK (pointer_motion), self);
+  g_signal_connect (controller, "leave", G_CALLBACK (pointer_leave), self);
+  gtk_widget_add_controller (GTK_WIDGET (self), controller);
+
+  self->active = TRUE;
+}
+
+static void
+gtk_maze_set_path (GtkMaze *self,
+                   GskPath *path)
+{
+  g_clear_pointer (&self->path, gsk_path_unref);
+  g_clear_pointer (&self->measure, gsk_path_measure_unref);
+  self->path = gsk_path_ref (path);
+  self->measure = gsk_path_measure_new (path);
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+GtkWidget *
+gtk_maze_new (GskPath      *path,
+              GdkPaintable *background,
+              int           width,
+              int           height)
+{
+  GtkMaze *self;
+
+  self = g_object_new (GTK_TYPE_MAZE, NULL);
+
+  gtk_maze_set_path (self, path);
+  gsk_path_unref (path);
+  self->background = background;
+  if (self->background)
+    {
+      g_signal_connect_swapped (self->background, "invalidate-contents", G_CALLBACK (gtk_widget_queue_draw), self);
+      g_signal_connect_swapped (self->background, "invalidate-size", G_CALLBACK (gtk_widget_queue_resize), self);
+    }
+  self->width = width;
+  self->height = height;
+
+  return GTK_WIDGET (self);
+}
+
+static void
+add_point_to_maze (GtkBitset      *maze,
+                   GskPathBuilder *builder,
+                   guint           x,
+                   guint           y)
+{
+  gboolean set[4] = { };
+  guint dir;
+
+  gtk_bitset_add (maze, y * MAZE_WIDTH + x);
+
+  while (TRUE)
+    {
+      set[0] = set[0] || x == 0 || gtk_bitset_contains (maze, y * MAZE_WIDTH + x - 1);
+      set[1] = set[1] || y == 0 || gtk_bitset_contains (maze, (y - 1) * MAZE_WIDTH + x);
+      set[2] = set[2] || x + 1 == MAZE_WIDTH || gtk_bitset_contains (maze, y * MAZE_WIDTH + x + 1);
+      set[3] = set[3] || y + 1 == MAZE_HEIGHT || gtk_bitset_contains (maze, (y + 1) * MAZE_WIDTH + x);
+
+      if (set[0] && set[1] && set[2] && set[3])
+        return;
+
+      do
+        {
+          dir = g_random_int_range (0, 4);
+        }
+      while (set[dir]);
+
+      switch (dir)
+        {
+          case 0:
+            gsk_path_builder_move_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            gsk_path_builder_line_to (builder, (x - 0.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            add_point_to_maze (maze, builder, x - 1, y);
+            break;
+
+          case 1:
+            gsk_path_builder_move_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            gsk_path_builder_line_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y - 0.5) * MAZE_GRID_SIZE);
+            add_point_to_maze (maze, builder, x, y - 1);
+            break;
+
+          case 2:
+            gsk_path_builder_move_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            gsk_path_builder_line_to (builder, (x + 1.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            add_point_to_maze (maze, builder, x + 1, y);
+            break;
+
+          case 3:
+            gsk_path_builder_move_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y + 0.5) * MAZE_GRID_SIZE);
+            gsk_path_builder_line_to (builder, (x + 0.5) * MAZE_GRID_SIZE, (y + 1.5) * MAZE_GRID_SIZE);
+            add_point_to_maze (maze, builder, x, y + 1);
+            break;
+
+          default:
+            g_assert_not_reached ();
+            break;
+        }
+    }
+}
+
+static GskPath *
+create_path_for_maze (GtkWidget *widget)
+{
+  GskPathBuilder *builder;
+  GtkBitset *maze;
+
+  builder = gsk_path_builder_new ();
+  maze = gtk_bitset_new_empty ();
+  /* make sure the outer lines are unreachable:
+   * Set the full range, then remove the center again. */
+  gtk_bitset_add_range (maze, 0, MAZE_WIDTH * MAZE_HEIGHT);
+  gtk_bitset_remove_rectangle (maze, MAZE_WIDTH + 1, MAZE_WIDTH - 2, MAZE_HEIGHT - 2, MAZE_WIDTH);
+
+  /* Fill the maze */
+  add_point_to_maze (maze, builder, MAZE_WIDTH / 2, MAZE_HEIGHT / 2);
+
+  /* Add start and stop lines */
+  gsk_path_builder_move_to (builder, 1.5 * MAZE_GRID_SIZE, -0.5 * MAZE_GRID_SIZE);
+  gsk_path_builder_line_to (builder, 1.5 * MAZE_GRID_SIZE, 1.5 * MAZE_GRID_SIZE);
+  gsk_path_builder_move_to (builder, (MAZE_WIDTH - 1.5) * MAZE_GRID_SIZE, (MAZE_HEIGHT - 1.5) * MAZE_GRID_SIZE);
+  gsk_path_builder_line_to (builder, (MAZE_WIDTH - 1.5) * MAZE_GRID_SIZE, (MAZE_HEIGHT + 0.5) * MAZE_GRID_SIZE);
+
+
+  gtk_bitset_unref (maze);
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+GtkWidget *
+do_path_maze (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkWidget *maze;
+      GtkMediaStream *stream;
+      GskPath *path;
+
+      window = gtk_window_new ();
+      gtk_window_set_resizable (GTK_WINDOW (window), TRUE);
+      gtk_window_set_title (GTK_WINDOW (window), "Follow the maze with the mouse");
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
+
+#if 0
+      stream = gtk_media_file_new_for_resource ("/images/gtk-logo.webm");
+#else
+      stream = gtk_nuclear_media_stream_new ();
+#endif
+      gtk_media_stream_play (stream);
+      gtk_media_stream_set_loop (stream, TRUE);
+
+      path = create_path_for_maze (window);
+
+      maze = gtk_maze_new (path,
+                           GDK_PAINTABLE (stream),
+                           MAZE_WIDTH * MAZE_GRID_SIZE,
+                           MAZE_HEIGHT * MAZE_GRID_SIZE);
+
+      gtk_window_set_child (GTK_WINDOW (window), maze);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_window_destroy (GTK_WINDOW (window));
+
+  return window;
+}

demos/gtk-demo/path_text.c

@@ -0,0 +1,594 @@
+/* Path/Curved Text
+ *
+ * This demo shows how to use GskPath to animate a path along another path.
+ */
+
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+
+#define GTK_TYPE_PATH_WIDGET (gtk_path_widget_get_type ())
+G_DECLARE_FINAL_TYPE (GtkPathWidget, gtk_path_widget, GTK, PATH_WIDGET, GtkWidget)
+
+#define POINT_SIZE 8
+
+enum {
+  PROP_0,
+  PROP_TEXT,
+  PROP_EDITABLE,
+  N_PROPS
+};
+
+struct _GtkPathWidget
+{
+  GtkWidget parent_instance;
+
+  char *text;
+  gboolean editable;
+
+  graphene_point_t points[4];
+
+  guint active_point;
+  float line_closest;
+
+  GskPath *line_path;
+  GskPathMeasure *line_measure;
+  GskPath *text_path;
+
+  GdkPaintable *background;
+};
+
+struct _GtkPathWidgetClass
+{
+  GtkWidgetClass parent_class;
+};
+
+static GParamSpec *properties[N_PROPS] = { NULL, };
+
+G_DEFINE_TYPE (GtkPathWidget, gtk_path_widget, GTK_TYPE_WIDGET)
+
+static GskPath *
+create_path_from_text (GtkWidget  *widget,
+                       const char *text)
+{
+  cairo_surface_t *surface;
+  cairo_t *cr;
+  cairo_path_t *path;
+  PangoLayout *layout;
+  PangoFontDescription *desc;
+  GskPath *result;
+
+  surface = cairo_recording_surface_create (CAIRO_CONTENT_COLOR_ALPHA, NULL);
+  cr = cairo_create (surface);
+
+  layout = gtk_widget_create_pango_layout (widget, text);
+  desc = pango_font_description_from_string ("sans bold 36");
+  pango_layout_set_font_description (layout, desc);
+  pango_font_description_free (desc);
+
+  cairo_move_to (cr, 0, - pango_layout_get_baseline (layout) / (double) PANGO_SCALE);
+  pango_cairo_layout_path (cr, layout);
+  path = cairo_copy_path (cr);
+  result = gsk_path_new_from_cairo (path);
+
+  cairo_path_destroy (path);
+  g_object_unref (layout);
+  cairo_destroy (cr);
+  cairo_surface_destroy (surface);
+
+  return result;
+}
+
+typedef struct
+{
+  GskPathMeasure *measure;
+  GskPathBuilder *builder;
+  double scale;
+} GtkPathTransform;
+
+static void
+gtk_path_transform_point (GskPathMeasure         *measure,
+                          const graphene_point_t *pt,
+                          float                   scale,
+                          graphene_point_t       *res)
+{
+  graphene_vec2_t tangent;
+
+  gsk_path_measure_get_point (measure, pt->x * scale, res, &tangent);
+
+  res->x -= pt->y * scale * graphene_vec2_get_y (&tangent);
+  res->y += pt->y * scale * graphene_vec2_get_x (&tangent);
+}
+
+static gboolean
+gtk_path_transform_op (GskPathOperation        op,
+                       const graphene_point_t *pts,
+                       gsize                   n_pts,
+                       float                   weight,
+                       gpointer                data)
+{
+  GtkPathTransform *transform = data;
+
+  switch (op)
+  {
+    case GSK_PATH_MOVE:
+      {
+        graphene_point_t res;
+        gtk_path_transform_point (transform->measure, &pts[0], transform->scale, &res);
+        gsk_path_builder_move_to (transform->builder, res.x, res.y);
+      }
+      break;
+
+    case GSK_PATH_LINE:
+      {
+        graphene_point_t res;
+        gtk_path_transform_point (transform->measure, &pts[1], transform->scale, &res);
+        gsk_path_builder_line_to (transform->builder, res.x, res.y);
+      }
+      break;
+
+    case GSK_PATH_CURVE:
+      {
+        graphene_point_t res[3];
+        gtk_path_transform_point (transform->measure, &pts[1], transform->scale, &res[0]);
+        gtk_path_transform_point (transform->measure, &pts[2], transform->scale, &res[1]);
+        gtk_path_transform_point (transform->measure, &pts[3], transform->scale, &res[2]);
+        gsk_path_builder_curve_to (transform->builder, res[0].x, res[0].y, res[1].x, res[1].y, res[2].x, res[2].y);
+      }
+      break;
+
+    case GSK_PATH_CONIC:
+      {
+        graphene_point_t res[2];
+        gtk_path_transform_point (transform->measure, &pts[1], transform->scale, &res[0]);
+        gtk_path_transform_point (transform->measure, &pts[2], transform->scale, &res[1]);
+        gsk_path_builder_conic_to (transform->builder, res[0].x, res[0].y, res[1].x, res[1].y, weight);
+      }
+      break;
+
+    case GSK_PATH_CLOSE:
+      gsk_path_builder_close (transform->builder);
+      break;
+
+    default:
+      g_assert_not_reached();
+      return FALSE;
+  }
+
+  return TRUE;
+}
+
+static GskPath *
+gtk_path_transform (GskPathMeasure *measure,
+                    GskPath        *path)
+{
+  GtkPathTransform transform = { measure, gsk_path_builder_new () };
+  graphene_rect_t bounds;
+
+  gsk_path_get_bounds (path, &bounds);
+  if (bounds.origin.x + bounds.size.width > 0)
+    transform.scale = gsk_path_measure_get_length (measure) / (bounds.origin.x + bounds.size.width);
+  else
+    transform.scale = 1.0f;
+
+  gsk_path_foreach (path, GSK_PATH_FOREACH_ALLOW_CURVE, gtk_path_transform_op, &transform);
+
+  return gsk_path_builder_free_to_path (transform.builder);
+}
+
+static void
+gtk_path_widget_clear_text_path (GtkPathWidget *self)
+{
+  g_clear_pointer (&self->text_path, gsk_path_unref);
+}
+
+static void
+gtk_path_widget_clear_paths (GtkPathWidget *self)
+{
+  gtk_path_widget_clear_text_path (self);
+
+  g_clear_pointer (&self->line_path, gsk_path_unref);
+  g_clear_pointer (&self->line_measure, gsk_path_measure_unref);
+}
+
+static void
+gtk_path_widget_create_text_path (GtkPathWidget *self)
+{
+  GskPath *path;
+
+  gtk_path_widget_clear_text_path (self);
+
+  if (self->line_measure == NULL)
+    return;
+
+  path = create_path_from_text (GTK_WIDGET (self), self->text);
+  self->text_path = gtk_path_transform (self->line_measure, path);
+
+  gsk_path_unref (path);
+}
+
+static void
+gtk_path_widget_create_paths (GtkPathWidget *self)
+{
+  double width = gtk_widget_get_width (GTK_WIDGET (self));
+  double height = gtk_widget_get_height (GTK_WIDGET (self));
+  GskPathBuilder *builder;
+
+  gtk_path_widget_clear_paths (self);
+
+  if (width <= 0 || height <= 0)
+    return;
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_move_to (builder,
+                            self->points[0].x * width, self->points[0].y * height);
+  gsk_path_builder_curve_to (builder,
+                             self->points[1].x * width, self->points[1].y * height,
+                             self->points[2].x * width, self->points[2].y * height,
+                             self->points[3].x * width, self->points[3].y * height);
+  self->line_path = gsk_path_builder_free_to_path (builder);
+
+  self->line_measure = gsk_path_measure_new (self->line_path);
+
+  gtk_path_widget_create_text_path (self);
+}
+
+static void
+gtk_path_widget_allocate (GtkWidget *widget,
+                          int        width,
+                          int        height,
+                          int        baseline)
+{
+  GtkPathWidget *self = GTK_PATH_WIDGET (widget);
+
+  GTK_WIDGET_CLASS (gtk_path_widget_parent_class)->size_allocate (widget, width, height, baseline);
+
+  gtk_path_widget_create_paths (self);
+}
+
+static void
+gtk_path_widget_snapshot (GtkWidget   *widget,
+                          GtkSnapshot *snapshot)
+{
+  GtkPathWidget *self = GTK_PATH_WIDGET (widget);
+  double width = gtk_widget_get_width (widget);
+  double height = gtk_widget_get_height (widget);
+  GskPath *path;
+  GskStroke *stroke;
+  gsize i;
+
+  /* frosted glass the background */
+  gtk_snapshot_push_blur (snapshot, 100);
+  gdk_paintable_snapshot (self->background, snapshot, width, height);
+  gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 1, 1, 1, 0.5 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+  gtk_snapshot_pop (snapshot);
+
+  /* draw the text */
+  if (self->text_path)
+    {
+      gtk_snapshot_push_fill (snapshot, self->text_path, GSK_FILL_RULE_WINDING);
+      gdk_paintable_snapshot (self->background, snapshot, width, height);
+
+      /* ... with an emboss effect */
+      stroke = gsk_stroke_new (2.0);
+      gtk_snapshot_translate (snapshot, &GRAPHENE_POINT_INIT(1, 1));
+      gtk_snapshot_push_stroke (snapshot, self->text_path, stroke);
+      gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 0, 0, 0, 0.2 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+      gsk_stroke_free (stroke);
+      gtk_snapshot_pop (snapshot);
+
+      gtk_snapshot_pop (snapshot);
+    }
+
+  if (self->editable && self->line_path)
+    {
+      /* draw the control line */
+      stroke = gsk_stroke_new (1.0);
+      gtk_snapshot_push_stroke (snapshot, self->line_path, stroke);
+      gsk_stroke_free (stroke);
+      gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 0, 0, 0, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+      gtk_snapshot_pop (snapshot);
+    }
+
+  if (self->line_closest >= 0)
+    {
+      GskPathBuilder *builder;
+      graphene_point_t closest;
+
+      builder = gsk_path_builder_new ();
+      gsk_path_measure_get_point (self->line_measure, self->line_closest, &closest, NULL);
+      gsk_path_builder_add_circle (builder, &closest, POINT_SIZE);
+      path = gsk_path_builder_free_to_path (builder);
+
+      gtk_snapshot_push_fill (snapshot, path, GSK_FILL_RULE_WINDING);
+      gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 0, 0, 1, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+      gtk_snapshot_pop (snapshot);
+
+      gsk_path_unref (path);
+    }
+
+  if (self->editable && self->line_path)
+    {
+      GskPathBuilder *builder;
+
+      /* draw the points */
+      builder = gsk_path_builder_new ();
+      for (i = 0; i < 4; i++)
+        {
+          gsk_path_builder_add_circle (builder, &GRAPHENE_POINT_INIT (self->points[i].x * width, self->points[i].y * height), POINT_SIZE);
+        }
+      path = gsk_path_builder_free_to_path (builder);
+
+      gtk_snapshot_push_fill (snapshot, path, GSK_FILL_RULE_WINDING);
+      gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 1, 1, 1, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+      gtk_snapshot_pop (snapshot);
+
+      stroke = gsk_stroke_new (1.0);
+      gtk_snapshot_push_stroke (snapshot, path, stroke);
+      gsk_stroke_free (stroke);
+      gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 0, 0, 0, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
+      gtk_snapshot_pop (snapshot);
+
+      gsk_path_unref (path);
+    }
+}
+
+static void
+gtk_path_widget_set_text (GtkPathWidget *self,
+                          const char    *text)
+{
+  if (g_strcmp0 (self->text, text) == 0)
+    return;
+
+  g_free (self->text);
+  self->text = g_strdup (text);
+
+  gtk_path_widget_create_paths (self);
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_TEXT]);
+}
+
+static void
+gtk_path_widget_set_editable (GtkPathWidget *self,
+                              gboolean       editable)
+{
+  if (self->editable == editable)
+    return;
+
+  self->editable = editable;
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_EDITABLE]);
+}
+
+static void
+gtk_path_widget_set_property (GObject      *object,
+                              guint         prop_id,
+                              const GValue *value,
+                              GParamSpec   *pspec)
+
+{
+  GtkPathWidget *self = GTK_PATH_WIDGET (object);
+
+  switch (prop_id)
+    {
+    case PROP_TEXT:
+      gtk_path_widget_set_text (self, g_value_get_string (value));
+      break;
+
+    case PROP_EDITABLE:
+      gtk_path_widget_set_editable (self, g_value_get_boolean (value));
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_path_widget_get_property (GObject    *object,
+                              guint       prop_id,
+                              GValue     *value,
+                              GParamSpec *pspec)
+{
+  GtkPathWidget *self = GTK_PATH_WIDGET (object);
+
+  switch (prop_id)
+    {
+    case PROP_TEXT:
+      g_value_set_string (value, self->text);
+      break;
+
+    case PROP_EDITABLE:
+      g_value_set_boolean (value, self->editable);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_path_widget_dispose (GObject *object)
+{
+  GtkPathWidget *self = GTK_PATH_WIDGET (object);
+
+  gtk_path_widget_clear_paths (self);
+
+  G_OBJECT_CLASS (gtk_path_widget_parent_class)->dispose (object);
+}
+
+static void
+gtk_path_widget_class_init (GtkPathWidgetClass *klass)
+{
+  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->dispose = gtk_path_widget_dispose;
+  object_class->set_property = gtk_path_widget_set_property;
+  object_class->get_property = gtk_path_widget_get_property;
+
+  widget_class->size_allocate = gtk_path_widget_allocate;
+  widget_class->snapshot = gtk_path_widget_snapshot;
+
+  properties[PROP_TEXT] =
+    g_param_spec_string ("text",
+                         "text",
+                         "Text transformed along a path",
+                         NULL,
+                         G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  properties[PROP_EDITABLE] =
+    g_param_spec_boolean ("editable",
+                          "editable",
+                          "If the path can be edited by the user",
+                          FALSE,
+                          G_PARAM_READWRITE | G_PARAM_EXPLICIT_NOTIFY | G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (object_class, N_PROPS, properties);
+}
+
+static void
+drag_begin (GtkGestureDrag *gesture,
+            double          x,
+            double          y,
+            GtkPathWidget  *self)
+{
+  graphene_point_t mouse = GRAPHENE_POINT_INIT (x, y);
+  double width = gtk_widget_get_width (GTK_WIDGET (self));
+  double height = gtk_widget_get_height (GTK_WIDGET (self));
+  gsize i;
+
+  for (i = 0; i < 4; i++)
+    {
+      if (graphene_point_distance (&GRAPHENE_POINT_INIT (self->points[i].x * width, self->points[i].y * height), &mouse, NULL, NULL) <= POINT_SIZE)
+        {
+          self->active_point = i;
+          break;
+        }
+    }
+  if (i == 4)
+    {
+      gtk_gesture_set_state (GTK_GESTURE (gesture), GTK_EVENT_SEQUENCE_DENIED);
+      return;
+    }
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+drag_update (GtkGestureDrag *drag,
+             double          offset_x,
+             double          offset_y,
+             GtkPathWidget  *self)
+{
+  double width = gtk_widget_get_width (GTK_WIDGET (self));
+  double height = gtk_widget_get_height (GTK_WIDGET (self));
+  double start_x, start_y;
+
+  gtk_gesture_drag_get_start_point (drag, &start_x, &start_y);
+
+  self->points[self->active_point] = GRAPHENE_POINT_INIT ((start_x + offset_x) / width,
+                                                          (start_y + offset_y) / height);
+  self->points[self->active_point].x = CLAMP (self->points[self->active_point].x, 0, 1);
+  self->points[self->active_point].y = CLAMP (self->points[self->active_point].y, 0, 1);
+
+  gtk_path_widget_create_paths (self);
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+pointer_motion (GtkEventControllerMotion *controller,
+                double                    x,
+                double                    y,
+                GtkPathWidget            *self)
+{
+  gsk_path_measure_get_closest_point_full (self->line_measure,
+                                           &GRAPHENE_POINT_INIT (x, y),
+                                           INFINITY,
+                                           NULL, NULL,
+                                           &self->line_closest,
+                                           NULL);
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+pointer_leave (GtkEventControllerMotion *controller,
+               GtkPathWidget            *self)
+{
+  self->line_closest = -1;
+
+  gtk_widget_queue_draw (GTK_WIDGET (self));
+}
+
+static void
+gtk_path_widget_init (GtkPathWidget *self)
+{
+  GtkEventController *controller;
+
+  controller = GTK_EVENT_CONTROLLER (gtk_gesture_drag_new ());
+  g_signal_connect (controller, "drag-begin", G_CALLBACK (drag_begin), self);
+  g_signal_connect (controller, "drag-update", G_CALLBACK (drag_update), self);
+  g_signal_connect (controller, "drag-end", G_CALLBACK (drag_update), self);
+  gtk_widget_add_controller (GTK_WIDGET (self), controller);
+
+  controller = GTK_EVENT_CONTROLLER (gtk_event_controller_motion_new ());
+  g_signal_connect (controller, "enter", G_CALLBACK (pointer_motion), self);
+  g_signal_connect (controller, "motion", G_CALLBACK (pointer_motion), self);
+  g_signal_connect (controller, "leave", G_CALLBACK (pointer_leave), self);
+  gtk_widget_add_controller (GTK_WIDGET (self), controller);
+
+  self->line_closest = -1;
+
+  self->points[0] = GRAPHENE_POINT_INIT (0.1, 0.9);
+  self->points[1] = GRAPHENE_POINT_INIT (0.3, 0.1);
+  self->points[2] = GRAPHENE_POINT_INIT (0.7, 0.1);
+  self->points[3] = GRAPHENE_POINT_INIT (0.9, 0.9);
+
+  self->background = GDK_PAINTABLE (gdk_texture_new_from_resource ("/sliding_puzzle/portland-rose.jpg"));
+
+  gtk_path_widget_set_text (self, "It's almost working");
+}
+
+GtkWidget *
+gtk_path_widget_new (void)
+{
+  GtkPathWidget *self;
+
+  self = g_object_new (GTK_TYPE_PATH_WIDGET, NULL);
+
+  return GTK_WIDGET (self);
+}
+
+GtkWidget *
+do_path_text (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkBuilder *builder;
+
+      g_type_ensure (GTK_TYPE_PATH_WIDGET);
+
+      builder = gtk_builder_new_from_resource ("/path_text/path_text.ui");
+      window = GTK_WIDGET (gtk_builder_get_object (builder, "window"));
+      gtk_window_set_display (GTK_WINDOW (window),
+                              gtk_widget_get_display (do_widget));
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *) &window);
+      g_object_unref (builder);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_window_destroy (GTK_WINDOW (window));
+
+  return window;
+}

demos/gtk-demo/path_text.ui

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <object class="GtkWindow" id="window">
+    <property name="title" translatable="yes">Text along a Path</property>
+    <child type="titlebar">
+      <object class="GtkHeaderBar">
+        <child type="end">
+          <object class="GtkToggleButton" id="edit-toggle">
+            <property name="icon-name">document-edit-symbolic</property>
+          </object>
+        </child>
+      </object>
+    </child>
+    <child>
+      <object class="GtkBox">
+        <property name="orientation">vertical</property>
+        <child>
+          <object class="GtkRevealer">
+            <property name="reveal-child" bind-source="edit-toggle" bind-property="active" bind-flags="sync-create"></property>
+            <child>
+              <object class="GtkEntry" id="text">
+                <property name="text">Through the looking glass</property>
+              </object>
+            </child>
+          </object>
+        </child>
+        <child>
+          <object class="GtkPathWidget" id="view">
+            <property name="editable" bind-source="edit-toggle" bind-property="active" bind-flags="sync-create"></property>
+            <property name="text" bind-source="text" bind-property="text" bind-flags="sync-create"></property>
+            <property name="hexpand">true</property>
+            <property name="vexpand">true</property>
+          </object>
+        </child>
+      </object>
+    </child>
+  </object>
+</interface>

docs/reference/gtk/meson.build

@@ -57,7 +57,7 @@ if get_option('gtk_doc')
   )
 endif
 
-rst2man = find_program('rst2man', required: false)
+rst2man = find_program('rst2man', 'rst2man.py', required: false)
 if get_option('man-pages') and not rst2man.found()
   error('No rst2man found, but man pages were explicitly enabled')
 endif

gdk/gdkevents.c

@@ -597,7 +597,8 @@ _gdk_event_unqueue (GdkDisplay *display)
 
 /*
  * If the last N events in the event queue are smooth scroll events
- * for the same surface and device, combine them into one.
+ * for the same surface, the same device and the same scroll unit,
+ * combine them into one.
  *
  * We give the remaining event a history with N items, and deltas
  * that are the sum over the history entries.
@@ -611,6 +612,8 @@ gdk_event_queue_handle_scroll_compression (GdkDisplay *display)
   GdkEvent *last_event = NULL;
   GList *scrolls = NULL;
   GArray *history = NULL;
+  GdkScrollUnit scroll_unit = GDK_SCROLL_UNIT_WHEEL;
+  gboolean scroll_unit_defined = FALSE;
   GdkTimeCoord hist;
 
   l = g_queue_peek_tail_link (&display->queued_events);
@@ -618,6 +621,7 @@ gdk_event_queue_handle_scroll_compression (GdkDisplay *display)
   while (l)
     {
       GdkEvent *event = l->data;
+      GdkScrollEvent *scroll_event = (GdkScrollEvent *) event;
 
       if (event->flags & GDK_EVENT_PENDING)
         break;
@@ -634,11 +638,17 @@ gdk_event_queue_handle_scroll_compression (GdkDisplay *display)
           device != event->device)
         break;
 
+      if (scroll_unit_defined &&
+          scroll_unit != scroll_event->unit)
+        break;
+
       if (!last_event)
         last_event = event;
 
       surface = event->surface;
       device = event->device;
+      scroll_unit = scroll_event->unit;
+      scroll_unit_defined = TRUE;
       scrolls = l;
 
       l = l->prev;
@@ -710,7 +720,8 @@ gdk_event_queue_handle_scroll_compression (GdkDisplay *display)
                                     gdk_event_get_modifier_state (old_event),
                                     dx,
                                     dy,
-                                    gdk_scroll_event_is_stop (old_event));
+                                    gdk_scroll_event_is_stop (old_event),
+                                    scroll_unit);
 
       ((GdkScrollEvent *)event)->history = history;
 
@@ -746,15 +757,21 @@ gdk_motion_event_push_history (GdkEvent *event,
 
   memset (&hist, 0, sizeof (GdkTimeCoord));
   hist.time = gdk_event_get_time (history_event);
+
   if (tool)
     {
       hist.flags = gdk_device_tool_get_axes (tool);
       for (i = GDK_AXIS_X; i < GDK_AXIS_LAST; i++)
         gdk_event_get_axis (history_event, i, &hist.axes[i]);
     }
-  else
+
+  /* GdkTimeCoord has no dedicated fields to record event position. For plain
+   * pointer events, and for tools which don't report GDK_AXIS_X/GDK_AXIS_Y
+   * on their own, we surface the position using the X and Y input axes.
+   */
+  if (!(hist.flags & GDK_AXIS_FLAG_X) || !(hist.flags & GDK_AXIS_FLAG_Y))
     {
-      hist.flags = GDK_AXIS_FLAG_X | GDK_AXIS_FLAG_Y;
+      hist.flags |= GDK_AXIS_FLAG_X | GDK_AXIS_FLAG_Y;
       gdk_event_get_position (history_event, &hist.axes[GDK_AXIS_X], &hist.axes[GDK_AXIS_Y]);
     }
 
@@ -2334,7 +2351,8 @@ gdk_scroll_event_new (GdkSurface      *surface,
                       GdkModifierType  state,
                       double           delta_x,
                       double           delta_y,
-                      gboolean         is_stop)
+                      gboolean         is_stop,
+                      GdkScrollUnit    unit)
 {
   GdkScrollEvent *self = gdk_event_alloc (GDK_SCROLL, surface, device, time);
 
@@ -2344,6 +2362,7 @@ gdk_scroll_event_new (GdkSurface      *surface,
   self->delta_x = delta_x;
   self->delta_y = delta_y;
   self->is_stop = is_stop;
+  self->unit = unit;
 
   return (GdkEvent *) self;
 }
@@ -2363,6 +2382,7 @@ gdk_scroll_event_new_discrete (GdkSurface         *surface,
   self->state = state;
   self->direction = direction;
   self->pointer_emulated = emulated;
+  self->unit = GDK_SCROLL_UNIT_WHEEL;
 
   return (GdkEvent *) self;
 }
@@ -2396,6 +2416,9 @@ gdk_scroll_event_get_direction (GdkEvent *event)
  *
  * The deltas will be zero unless the scroll direction
  * is %GDK_SCROLL_SMOOTH.
+ *
+ * For the representation unit of these deltas, see
+ * [method@Gdk.ScrollEvent.get_unit].
  */
 void
 gdk_scroll_event_get_deltas (GdkEvent *event,
@@ -2438,6 +2461,31 @@ gdk_scroll_event_is_stop (GdkEvent *event)
   return self->is_stop;
 }
 
+/**
+ * gdk_scroll_event_get_unit:
+ * @event: (type GdkScrollEvent): a scroll event.
+ *
+ * Extracts the scroll delta unit of a scroll event.
+ *
+ * The unit will always be %GDK_SCROLL_UNIT_WHEEL if the scroll direction is not
+ * %GDK_SCROLL_SMOOTH.
+ *
+ * Returns: the scroll unit.
+ *
+ * Since: 4.8
+ */
+GdkScrollUnit
+gdk_scroll_event_get_unit (GdkEvent *event)
+{
+  GdkScrollEvent *self = (GdkScrollEvent *) event;
+
+  g_return_val_if_fail (GDK_IS_EVENT (event), GDK_SCROLL_UNIT_WHEEL);
+  g_return_val_if_fail (GDK_IS_EVENT_TYPE (event, GDK_SCROLL),
+                        GDK_SCROLL_UNIT_WHEEL);
+
+  return self->unit;
+}
+
 /* }}} */
 
 /* {{{ GdkTouchpadEvent */

gdk/gdkevents.h

@@ -265,6 +265,37 @@ typedef enum
   GDK_SCROLL_SMOOTH
 } GdkScrollDirection;
 
+/**
+ * GdkScrollUnit:
+ * @GDK_SCROLL_UNIT_WHEEL: The delta is in number of wheel clicks.
+ * @GDK_SCROLL_UNIT_SURFACE: The delta is in surface pixels to scroll directly
+ *   on screen.
+ *
+ * Specifies the unit of scroll deltas.
+ *
+ * When you get %GDK_SCROLL_UNIT_WHEEL, a delta of 1.0 means 1 wheel detent
+ * click in the south direction, 2.0 means 2 wheel detent clicks in the south
+ * direction... This is the same logic for negative values but in the north
+ * direction.
+ *
+ * If you get %GDK_SCROLL_UNIT_SURFACE, are managing a scrollable view and get a
+ * value of 123, you have to scroll 123 surface logical pixels right if it's
+ * @delta_x or down if it's @delta_y. This is the same logic for negative values
+ * but you have to scroll left instead of right if it's @delta_x and up instead
+ * of down if it's @delta_y.
+ *
+ * 1 surface logical pixel is equal to 1 real screen pixel multiplied by the
+ * final scale factor of your graphical interface (the product of the desktop
+ * scale factor and eventually a custom scale factor in your app).
+ *
+ * Since: 4.8
+ */
+typedef enum
+{
+  GDK_SCROLL_UNIT_WHEEL,
+  GDK_SCROLL_UNIT_SURFACE
+} GdkScrollUnit;
+
 /**
  * GdkNotifyType:
  * @GDK_NOTIFY_ANCESTOR: the surface is entered from an ancestor or
@@ -395,6 +426,8 @@ GDK_AVAILABLE_IN_ALL
 void                    gdk_scroll_event_get_deltas     (GdkEvent *event,
                                                          double   *delta_x,
                                                          double   *delta_y);
+GDK_AVAILABLE_IN_4_8
+GdkScrollUnit           gdk_scroll_event_get_unit       (GdkEvent *event);
 
 GDK_AVAILABLE_IN_ALL
 gboolean                gdk_scroll_event_is_stop        (GdkEvent *event);

gdk/gdkeventsprivate.h

@@ -212,6 +212,7 @@ struct _GdkTouchEvent
  * @history: (element-type GdkTimeCoord): array of times and deltas
  *   for other scroll events that were compressed before delivering the
  *   current event
+ * @unit: The scroll unit in which delta_x and delta_y are represented.
  *
  * Generated from button presses for the buttons 4 to 7. Wheel mice are
  * usually configured to generate button press events for buttons 4 and 5
@@ -234,6 +235,7 @@ struct _GdkScrollEvent
   gboolean is_stop;
   GdkDeviceTool *tool;
   GArray *history; /* <GdkTimeCoord> */
+  GdkScrollUnit unit;
 };
 
 /*
@@ -486,7 +488,8 @@ GdkEvent * gdk_scroll_event_new         (GdkSurface      *surface,
                                          GdkModifierType  state,
                                          double           delta_x,
                                          double           delta_y,
-                                         gboolean         is_stop);
+                                         gboolean         is_stop,
+                                         GdkScrollUnit    unit);
 
 GdkEvent * gdk_scroll_event_new_discrete (GdkSurface         *surface,
                                           GdkDevice          *device,

gdk/gdkgltexture.c

@@ -365,6 +365,42 @@ gdk_gl_texture_determine_format (GdkGLTexture *self)
       texture->format = GDK_MEMORY_R32G32B32A32_FLOAT_PREMULTIPLIED;
       break;
 
+    case GL_RGBA:
+      {
+        GLint red_size = 0;
+        GLint green_size = 0;
+        GLint blue_size = 0;
+        GLint alpha_size = 0;
+        GLint red_type = 0;
+        GLint green_type = 0;
+        GLint blue_type = 0;
+        GLint alpha_type = 0;
+
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_RED_TYPE, &red_type);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_GREEN_TYPE, &green_type);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_BLUE_TYPE, &blue_type);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_ALPHA_TYPE, &alpha_type);
+
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_RED_SIZE, &red_size);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_GREEN_SIZE, &green_size);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_BLUE_SIZE, &blue_size);
+        glGetTexLevelParameteriv (GL_TEXTURE_2D, 0, GL_TEXTURE_ALPHA_SIZE, &alpha_size);
+
+#define CHECK_RGBA(rt,gt,bt,at,rs,gs,bs,as) \
+        (red_type == rt && green_type == gt && blue_type == bt && alpha_type == at && \
+         red_size == rs && green_size == gs && blue_size == bs && alpha_size == as)
+
+        if (CHECK_RGBA (GL_UNSIGNED_NORMALIZED, GL_UNSIGNED_NORMALIZED, GL_UNSIGNED_NORMALIZED, GL_UNSIGNED_NORMALIZED, 8, 8, 8, 8))
+          {
+            texture->format = GDK_MEMORY_R8G8B8A8_PREMULTIPLIED;
+            break;
+          }
+
+#undef CHECK_RGBA
+      }
+
+      G_GNUC_FALLTHROUGH;
+
     default:
       g_warning ("Texture in unexpected format 0x%X (%d). File a bug about adding it to GTK", internal_format, internal_format);
       /* fallback to the dumbest possible format

gdk/gdkintl.h

@@ -19,7 +19,7 @@
  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  * file for a list of people on the GTK+ Team.  See the ChangeLog
  * files for a list of changes.  These files are distributed with
- * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
+ * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  */
 
 #ifndef __GDKINTL_H__
@@ -27,10 +27,6 @@
 
 #include <glib/gi18n-lib.h>
 
-#ifdef ENABLE_NLS
-#define P_(String) dgettext(GETTEXT_PACKAGE "-properties",String)
-#else
-#define P_(String) (String)
-#endif
+#define P_(String) dgettext (GETTEXT_PACKAGE "-properties", String)
 
 #endif

gdk/gdksurface.c

@@ -1125,7 +1125,7 @@ gdk_surface_ensure_egl_surface (GdkSurface *self,
       gdk_display_get_egl_config_high_depth (display) != gdk_display_get_egl_config (display))
     {
       gdk_gl_context_clear_current_if_surface (self);
-      eglDestroySurface (gdk_surface_get_display (self), priv->egl_surface);
+      eglDestroySurface (gdk_display_get_egl_display (display), priv->egl_surface);
       priv->egl_surface = NULL;
     }
 

gdk/macos/GdkMacosWindow.c

@@ -171,6 +171,11 @@ typedef NSString *CALayerContentsGravity;
   return inMove;
 }
 
+- (BOOL)inFullscreenTransition;
+{
+  return inFullscreenTransition;
+}
+
 -(void)checkSendEnterNotify
 {
   /* When a new window has been created, and the mouse is in the window
@@ -759,31 +764,37 @@ typedef NSString *CALayerContentsGravity;
 
 -(void)windowWillEnterFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = YES;
   lastUnfullscreenFrame = [self frame];
 }
 
 -(void)windowDidEnterFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = NO;
   initialPositionKnown = NO;
   [self checkSendEnterNotify];
 }
 
 -(void)windowWillExitFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = YES;
 }
 
 -(void)windowDidExitFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = NO;
   initialPositionKnown = NO;
   [self checkSendEnterNotify];
 }
 
 -(void)windowDidFailToEnterFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = NO;
 }
 
 -(void)windowDidFailToExitFullScreen:(NSNotification *)aNotification
 {
+  inFullscreenTransition = NO;
 }
 
 -(void)windowDidChangeScreen:(NSNotification *)aNotification

gdk/macos/GdkMacosWindow.h

@@ -53,6 +53,7 @@
   NSRect           lastMaximizedFrame;
   NSRect           lastUnfullscreenFrame;
   BOOL             inMaximizeTransition;
+  BOOL             inFullscreenTransition;
 }
 
 -(void)beginManualMove;
@@ -70,5 +71,6 @@
 -(void)setDecorated:(BOOL)decorated;
 -(void)swapBuffer:(GdkMacosBuffer *)buffer withDamage:(const cairo_region_t *)damage;
 -(BOOL)needsMouseDownQuirk;
+-(BOOL)inFullscreenTransition;
 
 @end

gdk/macos/gdkmacosdisplay-translate.c

@@ -644,7 +644,8 @@ fill_scroll_event (GdkMacosDisplay *self,
                                  NULL,
                                  get_time_from_ns_event (nsevent),
                                  state,
-                                 0.0, 0.0, TRUE);
+                                 0.0, 0.0, TRUE,
+                                 GDK_SCROLL_UNIT_SURFACE);
 
   dx = [nsevent deltaX];
   dy = [nsevent deltaY];
@@ -665,7 +666,8 @@ fill_scroll_event (GdkMacosDisplay *self,
                                     state,
                                     -sx,
                                     -sy,
-                                    FALSE);
+                                    FALSE,
+                                    GDK_SCROLL_UNIT_SURFACE);
 
       /* Fall through for scroll emulation */
     }
@@ -714,7 +716,8 @@ fill_scroll_event (GdkMacosDisplay *self,
                                   NULL,
                                   get_time_from_ns_event (nsevent),
                                   state,
-                                  0.0, 0.0, TRUE);
+                                  0.0, 0.0, TRUE,
+                                  GDK_SCROLL_UNIT_SURFACE);
     }
 
   return g_steal_pointer (&ret);

gdk/macos/gdkmacosdisplay.c

@@ -434,7 +434,8 @@ select_key_in_idle_cb (gpointer data)
         {
           GdkMacosSurface *surface = iter->data;
 
-          if (GDK_SURFACE_IS_MAPPED (GDK_SURFACE (surface)))
+          if (GDK_SURFACE_IS_MAPPED (GDK_SURFACE (surface)) &&
+              ([surface->window styleMask] & NSWindowStyleMaskMiniaturizable) == 0)
             {
               [surface->window showAndMakeKey:YES];
               break;

gdk/macos/gdkmacostoplevelsurface.c

@@ -33,26 +33,26 @@
 static void
 _gdk_macos_toplevel_surface_fullscreen (GdkMacosToplevelSurface *self)
 {
-  NSWindow *window;
+  GdkMacosWindow *window;
 
   g_assert (GDK_IS_MACOS_TOPLEVEL_SURFACE (self));
 
-  window = _gdk_macos_surface_get_native (GDK_MACOS_SURFACE (self));
+  window = (GdkMacosWindow *)_gdk_macos_surface_get_native (GDK_MACOS_SURFACE (self));
 
-  if (([window styleMask] & NSWindowStyleMaskFullScreen) == 0)
+  if (![window inFullscreenTransition] && ([window styleMask] & NSWindowStyleMaskFullScreen) == 0)
     [window toggleFullScreen:window];
 }
 
 static void
 _gdk_macos_toplevel_surface_unfullscreen (GdkMacosToplevelSurface *self)
 {
-  NSWindow *window;
+  GdkMacosWindow *window;
 
   g_assert (GDK_IS_MACOS_TOPLEVEL_SURFACE (self));
 
-  window = _gdk_macos_surface_get_native (GDK_MACOS_SURFACE (self));
+  window = (GdkMacosWindow *)_gdk_macos_surface_get_native (GDK_MACOS_SURFACE (self));
 
-  if (([window styleMask] & NSWindowStyleMaskFullScreen) != 0)
+  if (![window inFullscreenTransition] && ([window styleMask] & NSWindowStyleMaskFullScreen) != 0)
     [window toggleFullScreen:window];
 }
 
@@ -82,6 +82,19 @@ _gdk_macos_toplevel_surface_unmaximize (GdkMacosToplevelSurface *self)
     [window zoom:window];
 }
 
+static void
+_gdk_macos_toplevel_surface_unminimize (GdkMacosToplevelSurface *self)
+{
+  NSWindow *window;
+
+  g_assert (GDK_IS_MACOS_TOPLEVEL_SURFACE (self));
+
+  window = _gdk_macos_surface_get_native (GDK_MACOS_SURFACE (self));
+
+  if ([window isMiniaturized])
+    [window deminiaturize:window];
+}
+
 static void
 _gdk_macos_toplevel_surface_present (GdkToplevel       *toplevel,
                                      GdkToplevelLayout *layout)
@@ -202,6 +215,8 @@ _gdk_macos_toplevel_surface_present (GdkToplevel       *toplevel,
         _gdk_macos_toplevel_surface_unfullscreen (self);
     }
 
+  _gdk_macos_toplevel_surface_unminimize (self);
+
   if (!GDK_MACOS_SURFACE (self)->did_initial_present)
     {
       int x = 0, y = 0;

gdk/wayland/gdkdevice-wayland.c

@@ -1416,7 +1416,8 @@ flush_smooth_scroll_event (GdkWaylandSeat *seat,
                                 seat->pointer_info.time,
                                 device_get_modifiers (seat->logical_pointer),
                                 delta_x, delta_y,
-                                is_stop);
+                                is_stop,
+                                GDK_SCROLL_UNIT_SURFACE);
 
   _gdk_wayland_display_deliver_event (seat->display, event);
 }
@@ -1755,10 +1756,10 @@ pointer_handle_axis (void              *data,
   switch (axis)
     {
     case WL_POINTER_AXIS_VERTICAL_SCROLL:
-      pointer_frame->delta_y = wl_fixed_to_double (value) / 10.0;
+      pointer_frame->delta_y = wl_fixed_to_double (value);
       break;
     case WL_POINTER_AXIS_HORIZONTAL_SCROLL:
-      pointer_frame->delta_x = wl_fixed_to_double (value) / 10.0;
+      pointer_frame->delta_x = wl_fixed_to_double (value);
       break;
     default:
       g_return_if_reached ();
@@ -1768,7 +1769,7 @@ pointer_handle_axis (void              *data,
 
   GDK_SEAT_NOTE (seat, EVENTS,
             g_message ("scroll, axis %s, value %f, seat %p",
-                       get_axis_name (axis), wl_fixed_to_double (value) / 10.0,
+                       get_axis_name (axis), wl_fixed_to_double (value),
                        seat));
 
   if (display->seat_version < WL_POINTER_HAS_FRAME)
@@ -3994,7 +3995,8 @@ tablet_tool_handle_wheel (void                      *data,
                                 tablet->pointer_info.time,
                                 device_get_modifiers (tablet->logical_device),
                                 0, clicks,
-                                FALSE);
+                                FALSE,
+                                GDK_SCROLL_UNIT_WHEEL);
 
   _gdk_wayland_display_deliver_event (seat->display, event);
 

gdk/win32/gdkclipboard-win32.c

@@ -142,9 +142,13 @@ gdk_win32_clipboard_claim_remote (GdkWin32Clipboard *cb)
   cb->sequence_number = -1;
 
   formats = gdk_win32_clipboard_request_contentformats (cb);
-  gdk_clipboard_claim_remote (GDK_CLIPBOARD (cb), formats);
-  gdk_content_formats_unref (formats);
-  cb->sequence_number = GetClipboardSequenceNumber ();
+
+  if (formats != NULL)
+    {
+      gdk_clipboard_claim_remote (GDK_CLIPBOARD (cb), formats);
+      gdk_content_formats_unref (formats);
+      cb->sequence_number = GetClipboardSequenceNumber ();
+    }
 }
 
 static void

gdk/win32/gdkevents-win32.c

@@ -2742,7 +2742,8 @@ gdk_event_translate (MSG *msg,
                                     build_pointer_event_state (msg),
                                     delta_x,
                                     delta_y,
-                                    FALSE);
+                                    FALSE,
+                                    GDK_SCROLL_UNIT_WHEEL);
 
       /* Append the discrete version too */
       direction = 0;

gdk/x11/gdkclipboard-x11.c

@@ -248,6 +248,10 @@ gdk_x11_clipboard_formats_from_atoms (GdkDisplay *display,
       const char *name;
 
       name = gdk_x11_get_xatom_name_for_display (display , atoms[i]);
+      if (!name)
+        {
+          continue;
+        }
       if (strchr (name, '/'))
         {
           gdk_content_formats_builder_add_mime_type (builder, name);

gdk/x11/gdkdevicemanager-xi2.c

@@ -1778,7 +1778,8 @@ gdk_x11_device_manager_xi2_translate_event (GdkEventTranslator *translator,
                                               state,
                                               delta_x,
                                               delta_y,
-                                              delta_x == 0.0 && delta_y == 0.0);
+                                              delta_x == 0.0 && delta_y == 0.0,
+                                              GDK_SCROLL_UNIT_WHEEL);
               }
             break;
           }

gsk/broadway/gskbroadwayrenderer.c

@@ -269,6 +269,8 @@ collect_reused_child_nodes (GskRenderer *renderer,
     case GSK_BLEND_NODE:
     case GSK_CROSS_FADE_NODE:
     case GSK_BLUR_NODE:
+    case GSK_FILL_NODE:
+    case GSK_STROKE_NODE:
 
     default:
 
@@ -855,6 +857,8 @@ gsk_broadway_renderer_add_node (GskRenderer *renderer,
     case GSK_CROSS_FADE_NODE:
     case GSK_BLUR_NODE:
     case GSK_GL_SHADER_NODE:
+    case GSK_FILL_NODE:
+    case GSK_STROKE_NODE:
     default:
       break; /* Fallback */
     }

gsk/gl/gskglcommandqueue.c

@@ -282,7 +282,7 @@ snapshot_uniforms (GskGLUniformState    *state,
     {
       const GskGLUniformMapping *mapping = &program->mappings[i];
 
-      if (!mapping->info.initial && mapping->location > -1)
+      if (!mapping->info.initial && mapping->info.format && mapping->location > -1)
         {
           uniform[count].location = mapping->location;
           uniform[count].info = mapping->info;

gsk/gl/gskgldriver.c

@@ -44,9 +44,6 @@
 #include <gdk/gdkprofilerprivate.h>
 #include <gdk/gdktextureprivate.h>
 
-#define ATLAS_SIZE 512
-#define MAX_OLD_RATIO 0.5
-
 G_DEFINE_TYPE (GskGLDriver, gsk_gl_driver, G_TYPE_OBJECT)
 
 static guint
@@ -156,50 +153,6 @@ gsk_gl_driver_collect_unused_textures (GskGLDriver *self,
   return collected;
 }
 
-static void
-gsk_gl_texture_atlas_free (GskGLTextureAtlas *atlas)
-{
-  if (atlas->texture_id != 0)
-    {
-      glDeleteTextures (1, &atlas->texture_id);
-      atlas->texture_id = 0;
-    }
-
-  g_clear_pointer (&atlas->nodes, g_free);
-  g_slice_free (GskGLTextureAtlas, atlas);
-}
-
-GskGLTextureAtlas *
-gsk_gl_driver_create_atlas (GskGLDriver *self)
-{
-  GskGLTextureAtlas *atlas;
-
-  g_return_val_if_fail (GSK_IS_GL_DRIVER (self), NULL);
-
-  atlas = g_slice_new0 (GskGLTextureAtlas);
-  atlas->width = ATLAS_SIZE;
-  atlas->height = ATLAS_SIZE;
-  /* TODO: We might want to change the strategy about the amount of
-   *       nodes here? stb_rect_pack.h says width is optimal. */
-  atlas->nodes = g_malloc0_n (atlas->width, sizeof (struct stbrp_node));
-  stbrp_init_target (&atlas->context, atlas->width, atlas->height, atlas->nodes, atlas->width);
-  atlas->texture_id = gsk_gl_command_queue_create_texture (self->command_queue,
-                                                           atlas->width,
-                                                           atlas->height,
-                                                           GL_RGBA8,
-                                                           GL_LINEAR,
-                                                           GL_LINEAR);
-
-  gdk_gl_context_label_object_printf (gdk_gl_context_get_current (),
-                                      GL_TEXTURE, atlas->texture_id,
-                                      "Texture atlas %d",
-                                      atlas->texture_id);
-
-  g_ptr_array_add (self->atlases, atlas);
-
-  return atlas;
-}
-
 static void
 remove_program (gpointer data)
 {
@@ -226,6 +179,29 @@ gsk_gl_driver_shader_weak_cb (gpointer  data,
     g_hash_table_remove (self->shader_cache, where_object_was);
 }
 
+G_GNUC_NULL_TERMINATED static inline GBytes *
+join_sources (GBytes *first_bytes,
+              ...)
+{
+  GByteArray *byte_array = g_byte_array_new ();
+  GBytes *bytes = first_bytes;
+  va_list args;
+
+  va_start (args, first_bytes);
+  while (bytes != NULL)
+    {
+      gsize len;
+      const guint8 *data = g_bytes_get_data (bytes, &len);
+      if (len > 0)
+        g_byte_array_append (byte_array, data, len);
+      g_bytes_unref (bytes);
+      bytes = va_arg (args, GBytes *);
+    }
+  va_end (args);
+
+  return g_byte_array_free_to_bytes (byte_array);
+}
+
 static void
 gsk_gl_driver_dispose (GObject *object)
 {
@@ -235,6 +211,10 @@ gsk_gl_driver_dispose (GObject *object)
   g_assert (self->in_frame == FALSE);
 
 #define GSK_GL_NO_UNIFORMS
+#define GSK_GL_SHADER_RESOURCE(name)
+#define GSK_GL_SHADER_STRING(str)
+#define GSK_GL_SHADER_SINGLE(name)
+#define GSK_GL_SHADER_JOINED(kind, ...)
 #define GSK_GL_ADD_UNIFORM(pos, KEY, name)
 #define GSK_GL_DEFINE_PROGRAM(name, resource, uniforms) \
   GSK_GL_DELETE_PROGRAM(name);                          \
@@ -248,6 +228,10 @@ gsk_gl_driver_dispose (GObject *object)
   } G_STMT_END;
 # include "gskglprograms.defs"
 #undef GSK_GL_NO_UNIFORMS
+#undef GSK_GL_SHADER_RESOURCE
+#undef GSK_GL_SHADER_STRING
+#undef GSK_GL_SHADER_SINGLE
+#undef GSK_GL_SHADER_JOINED
 #undef GSK_GL_ADD_UNIFORM
 #undef GSK_GL_DEFINE_PROGRAM
 
@@ -289,11 +273,10 @@ gsk_gl_driver_dispose (GObject *object)
   g_assert (!self->texture_id_to_key || g_hash_table_size (self->texture_id_to_key) == 0);
   g_assert (!self->key_to_texture_id|| g_hash_table_size (self->key_to_texture_id) == 0);
 
-  g_clear_object (&self->glyphs);
-  g_clear_object (&self->icons);
-  g_clear_object (&self->shadows);
+  g_clear_object (&self->glyphs_library);
+  g_clear_object (&self->icons_library);
+  g_clear_object (&self->shadows_library);
 
-  g_clear_pointer (&self->atlases, g_ptr_array_unref);
   g_clear_pointer (&self->autorelease_framebuffers, g_array_unref);
   g_clear_pointer (&self->key_to_texture_id, g_hash_table_unref);
   g_clear_pointer (&self->textures, g_hash_table_unref);
@@ -330,7 +313,6 @@ gsk_gl_driver_init (GskGLDriver *self)
   self->shader_cache = g_hash_table_new_full (NULL, NULL, NULL, remove_program);
   self->texture_pool = g_array_new (FALSE, FALSE, sizeof (guint));
   self->render_targets = g_ptr_array_new ();
-  self->atlases = g_ptr_array_new_with_free_func ((GDestroyNotify)gsk_gl_texture_atlas_free);
 }
 
 static gboolean
@@ -348,14 +330,14 @@ gsk_gl_driver_load_programs (GskGLDriver  *self,
 
   /* Setup preambles that are shared by all shaders */
   gsk_gl_compiler_set_preamble_from_resource (compiler,
-                                               GSK_GL_COMPILER_ALL,
-                                               "/org/gtk/libgsk/gl/preamble.glsl");
+                                              GSK_GL_COMPILER_ALL,
+                                              "/org/gtk/libgsk/gl/preamble.glsl");
   gsk_gl_compiler_set_preamble_from_resource (compiler,
-                                               GSK_GL_COMPILER_VERTEX,
-                                               "/org/gtk/libgsk/gl/preamble.vs.glsl");
+                                              GSK_GL_COMPILER_VERTEX,
+                                              "/org/gtk/libgsk/gl/preamble.vs.glsl");
   gsk_gl_compiler_set_preamble_from_resource (compiler,
-                                               GSK_GL_COMPILER_FRAGMENT,
-                                               "/org/gtk/libgsk/gl/preamble.fs.glsl");
+                                              GSK_GL_COMPILER_FRAGMENT,
+                                              "/org/gtk/libgsk/gl/preamble.fs.glsl");
 
   /* Setup attributes that are provided via VBO */
   gsk_gl_compiler_bind_attribute (compiler, "aPosition", 0);
@@ -365,10 +347,28 @@ gsk_gl_driver_load_programs (GskGLDriver  *self,
 
   /* Use XMacros to register all of our programs and their uniforms */
 #define GSK_GL_NO_UNIFORMS
+#define GSK_GL_SHADER_RESOURCE(name)                                                            \
+  g_resources_lookup_data("/org/gtk/libgsk/gl/" name, 0, NULL)
+#define GSK_GL_SHADER_STRING(str)                                                               \
+  g_bytes_new_static(str, strlen(str))
+#define GSK_GL_SHADER_SINGLE(bytes)                                                             \
+  G_STMT_START {                                                                                \
+    GBytes *b = bytes;                                                                          \
+    gsk_gl_compiler_set_source (compiler, GSK_GL_COMPILER_ALL, b);                              \
+    g_bytes_unref (b);                                                                          \
+  } G_STMT_END;
+#define GSK_GL_SHADER_JOINED(kind, ...)                                                         \
+  G_STMT_START {                                                                                \
+    GBytes *bytes = join_sources(__VA_ARGS__);                                                  \
+    gsk_gl_compiler_set_source (compiler, GSK_GL_COMPILER_##kind, bytes);                       \
+    g_bytes_unref (bytes);                                                                      \
+  } G_STMT_END;
 #define GSK_GL_ADD_UNIFORM(pos, KEY, name)                                                      \
   gsk_gl_program_add_uniform (program, #name, UNIFORM_##KEY);
-#define GSK_GL_DEFINE_PROGRAM(name, resource, uniforms)                                         \
-  gsk_gl_compiler_set_source_from_resource (compiler, GSK_GL_COMPILER_ALL, resource);           \
+#define GSK_GL_DEFINE_PROGRAM(name, sources, uniforms)                                          \
+  gsk_gl_compiler_set_source (compiler, GSK_GL_COMPILER_VERTEX, NULL);                          \
+  gsk_gl_compiler_set_source (compiler, GSK_GL_COMPILER_FRAGMENT, NULL);                        \
+  sources                                                                                       \
   GSK_GL_COMPILE_PROGRAM(name ## _no_clip, uniforms, "#define NO_CLIP 1\n");                    \
   GSK_GL_COMPILE_PROGRAM(name ## _rect_clip, uniforms, "#define RECT_CLIP 1\n");                \
   GSK_GL_COMPILE_PROGRAM(name, uniforms, "");
@@ -401,6 +401,11 @@ gsk_gl_driver_load_programs (GskGLDriver  *self,
 #undef GSK_GL_DEFINE_PROGRAM_CLIP
 #undef GSK_GL_DEFINE_PROGRAM
 #undef GSK_GL_ADD_UNIFORM
+#undef GSK_GL_SHADER_SINGLE
+#undef GSK_GL_SHADER_JOINED
+#undef GSK_GL_SHADER_RESOURCE
+#undef GSK_GL_SHADER_STRING
+#undef GSK_GL_NO_UNIFORMS
 
   ret = TRUE;
 
@@ -456,9 +461,9 @@ gsk_gl_driver_new (GskGLCommandQueue  *command_queue,
       return NULL;
     }
 
-  self->glyphs = gsk_gl_glyph_library_new (self);
-  self->icons = gsk_gl_icon_library_new (self);
-  self->shadows = gsk_gl_shadow_library_new (self);
+  self->glyphs_library = gsk_gl_glyph_library_new (self);
+  self->icons_library = gsk_gl_icon_library_new (self);
+  self->shadows_library = gsk_gl_shadow_library_new (self);
 
   gdk_profiler_end_mark (before, "create GskGLDriver", NULL);
 
@@ -518,37 +523,6 @@ failure:
   return g_steal_pointer (&driver);
 }
 
-static GPtrArray *
-gsk_gl_driver_compact_atlases (GskGLDriver *self)
-{
-  GPtrArray *removed = NULL;
-
-  g_assert (GSK_IS_GL_DRIVER (self));
-
-  for (guint i = self->atlases->len; i > 0; i--)
-    {
-      GskGLTextureAtlas *atlas = g_ptr_array_index (self->atlases, i - 1);
-
-      if (gsk_gl_texture_atlas_get_unused_ratio (atlas) > MAX_OLD_RATIO)
-        {
-          GSK_NOTE (GLYPH_CACHE,
-                    g_message ("Dropping atlas %d (%g.2%% old)", i,
-                               100.0 * gsk_gl_texture_atlas_get_unused_ratio (atlas)));
-          if (removed == NULL)
-            removed = g_ptr_array_new_with_free_func ((GDestroyNotify)gsk_gl_texture_atlas_free);
-          g_ptr_array_add (removed, g_ptr_array_steal_index (self->atlases, i - 1));
-        }
-    }
-
-  GSK_NOTE (GLYPH_CACHE, {
-    static guint timestamp;
-    if (timestamp++ % 60 == 0)
-      g_message ("%d atlases", self->atlases->len);
-  });
-
-  return removed;
-}
-
 /**
  * gsk_gl_driver_begin_frame:
  * @self: a `GskGLDriver`
@@ -565,7 +539,6 @@ gsk_gl_driver_begin_frame (GskGLDriver       *self,
                            GskGLCommandQueue *command_queue)
 {
   gint64 last_frame_id;
-  GPtrArray *removed;
 
   g_return_if_fail (GSK_IS_GL_DRIVER (self));
   g_return_if_fail (GSK_IS_GL_COMMAND_QUEUE (command_queue));
@@ -580,19 +553,14 @@ gsk_gl_driver_begin_frame (GskGLDriver       *self,
 
   gsk_gl_command_queue_begin_frame (self->command_queue);
 
-  /* Compact atlases with too many freed pixels */
-  removed = gsk_gl_driver_compact_atlases (self);
-
   /* Mark unused pixel regions of the atlases */
-  gsk_gl_texture_library_begin_frame (GSK_GL_TEXTURE_LIBRARY (self->icons),
-                                       self->current_frame_id,
-                                       removed);
-  gsk_gl_texture_library_begin_frame (GSK_GL_TEXTURE_LIBRARY (self->glyphs),
-                                       self->current_frame_id,
-                                       removed);
+  gsk_gl_texture_library_begin_frame (GSK_GL_TEXTURE_LIBRARY (self->icons_library),
+                                      self->current_frame_id);
+  gsk_gl_texture_library_begin_frame (GSK_GL_TEXTURE_LIBRARY (self->glyphs_library),
+                                      self->current_frame_id);
 
   /* Cleanup old shadows */
-  gsk_gl_shadow_library_begin_frame (self->shadows);
+  gsk_gl_shadow_library_begin_frame (self->shadows_library);
 
   /* Remove all textures that are from a previous frame or are no
    * longer used by linked GdkTexture. We do this at the beginning
@@ -600,9 +568,6 @@ gsk_gl_driver_begin_frame (GskGLDriver       *self,
    * we block on any resources while delivering our frames.
    */
   gsk_gl_driver_collect_unused_textures (self, last_frame_id - 1);
-
-  /* Now free atlas textures */
-  g_clear_pointer (&removed, g_ptr_array_unref);
 }
 
 /**
@@ -1182,14 +1147,23 @@ void
 gsk_gl_driver_save_atlases_to_png (GskGLDriver *self,
                                    const char  *directory)
 {
+  GPtrArray *atlases;
+
   g_return_if_fail (GSK_IS_GL_DRIVER (self));
 
   if (directory == NULL)
     directory = ".";
 
-  for (guint i = 0; i < self->atlases->len; i++)
+#define copy_atlases(dst, library) \
+  g_ptr_array_extend(dst, GSK_GL_TEXTURE_LIBRARY(library)->atlases, NULL, NULL)
+  atlases = g_ptr_array_new ();
+  copy_atlases (atlases, self->glyphs_library);
+  copy_atlases (atlases, self->icons_library);
+#undef copy_atlases
+
+  for (guint i = 0; i < atlases->len; i++)
     {
-      GskGLTextureAtlas *atlas = g_ptr_array_index (self->atlases, i);
+      GskGLTextureAtlas *atlas = g_ptr_array_index (atlases, i);
       char *filename = g_strdup_printf ("%s%sframe-%d-atlas-%d.png",
                                         directory,
                                         G_DIR_SEPARATOR_S,
@@ -1198,6 +1172,8 @@ gsk_gl_driver_save_atlases_to_png (GskGLDriver *self,
       write_atlas_to_png (self, atlas, filename);
       g_free (filename);
     }
+
+  g_ptr_array_unref (atlases);
 }
 #endif
 

gsk/gl/gskgldriverprivate.h

@@ -100,17 +100,15 @@ struct _GskGLDriver
   GskGLCommandQueue *shared_command_queue;
   GskGLCommandQueue *command_queue;
 
-  GskGLGlyphLibrary *glyphs;
-  GskGLIconLibrary *icons;
-  GskGLShadowLibrary *shadows;
+  GskGLGlyphLibrary *glyphs_library;
+  GskGLIconLibrary *icons_library;
+  GskGLShadowLibrary *shadows_library;
 
   GArray *texture_pool;
   GHashTable *textures;
   GHashTable *key_to_texture_id;
   GHashTable *texture_id_to_key;
 
-  GPtrArray *atlases;
-
   GHashTable *shader_cache;
 
   GArray *autorelease_framebuffers;
@@ -184,7 +182,6 @@ void                gsk_gl_driver_add_texture_slices     (GskGLDriver         *s
 GskGLProgram      * gsk_gl_driver_lookup_shader          (GskGLDriver         *self,
                                                           GskGLShader         *shader,
                                                           GError             **error);
-GskGLTextureAtlas * gsk_gl_driver_create_atlas           (GskGLDriver         *self);
 
 #ifdef G_ENABLE_DEBUG
 void                gsk_gl_driver_save_atlases_to_png    (GskGLDriver         *self,

gsk/gl/gskglglyphlibrary.c

@@ -84,15 +84,64 @@ gsk_gl_glyph_value_free (gpointer data)
 }
 
 static void
-gsk_gl_glyph_library_begin_frame (GskGLTextureLibrary *library,
-                                  gint64               frame_id,
-                                  GPtrArray           *removed_atlases)
+gsk_gl_glyph_library_clear_cache (GskGLTextureLibrary *library)
 {
   GskGLGlyphLibrary *self = (GskGLGlyphLibrary *)library;
 
+  g_assert (GSK_IS_GL_GLYPH_LIBRARY (self));
+
   memset (self->front, 0, sizeof self->front);
 }
 
+static void
+gsk_gl_glyph_library_init_atlas (GskGLTextureLibrary *self,
+                                 GskGLTextureAtlas   *atlas)
+{
+  gboolean packed G_GNUC_UNUSED;
+  int x, y;
+  guint gl_format;
+  guint gl_type;
+  guint8 pixel_data[4 * 3 * 3];
+
+  g_assert (GSK_IS_GL_GLYPH_LIBRARY (self));
+  g_assert (atlas != NULL);
+
+  /* Insert a single pixel at 0,0 for use in coloring */
+
+  gdk_gl_context_push_debug_group_printf (gdk_gl_context_get_current (),
+                                          "Initializing Atlas");
+
+  packed = gsk_gl_texture_library_allocate (self, atlas, 3, 3, &x, &y);
+  g_assert (packed);
+  g_assert (x == 0 && y == 0);
+
+  memset (pixel_data, 255, sizeof pixel_data);
+
+  if (gdk_gl_context_get_use_es (gdk_gl_context_get_current ()))
+    {
+      gl_format = GL_RGBA;
+      gl_type = GL_UNSIGNED_BYTE;
+    }
+  else
+    {
+      gl_format = GL_BGRA;
+      gl_type = GL_UNSIGNED_INT_8_8_8_8_REV;
+    }
+
+  glBindTexture (GL_TEXTURE_2D, atlas->texture_id);
+
+  glTexSubImage2D (GL_TEXTURE_2D, 0,
+                   0, 0,
+                   3, 3,
+                   gl_format, gl_type,
+                   pixel_data);
+
+  gdk_gl_context_pop_debug_group (gdk_gl_context_get_current ());
+
+  self->driver->command_queue->n_uploads++;
+}
+
+
 static void
 gsk_gl_glyph_library_finalize (GObject *object)
 {
@@ -111,7 +160,8 @@ gsk_gl_glyph_library_class_init (GskGLGlyphLibraryClass *klass)
 
   object_class->finalize = gsk_gl_glyph_library_finalize;
 
-  library_class->begin_frame = gsk_gl_glyph_library_begin_frame;
+  library_class->clear_cache = gsk_gl_glyph_library_clear_cache;
+  library_class->init_atlas = gsk_gl_glyph_library_init_atlas;
 }
 
 static void

gsk/gl/gskglprograms.defs

@@ -1,71 +1,71 @@
 GSK_GL_DEFINE_PROGRAM (blend,
-                       "/org/gtk/libgsk/gl/blend.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("blend.glsl")),
                        GSK_GL_ADD_UNIFORM (1, BLEND_SOURCE2, u_source2)
                        GSK_GL_ADD_UNIFORM (2, BLEND_MODE, u_mode))
 
 GSK_GL_DEFINE_PROGRAM (blit,
-                       "/org/gtk/libgsk/gl/blit.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("blit.glsl")),
                        GSK_GL_NO_UNIFORMS)
 
 GSK_GL_DEFINE_PROGRAM (blur,
-                       "/org/gtk/libgsk/gl/blur.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("blur.glsl")),
                        GSK_GL_ADD_UNIFORM (1, BLUR_RADIUS, u_blur_radius)
                        GSK_GL_ADD_UNIFORM (2, BLUR_SIZE, u_blur_size)
                        GSK_GL_ADD_UNIFORM (3, BLUR_DIR, u_blur_dir))
 
 GSK_GL_DEFINE_PROGRAM (border,
-                       "/org/gtk/libgsk/gl/border.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("border.glsl")),
                        GSK_GL_ADD_UNIFORM (1, BORDER_WIDTHS, u_widths)
                        GSK_GL_ADD_UNIFORM (2, BORDER_OUTLINE_RECT, u_outline_rect))
 
 GSK_GL_DEFINE_PROGRAM (color,
-                       "/org/gtk/libgsk/gl/color.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("color.glsl")),
                        GSK_GL_NO_UNIFORMS)
 
 GSK_GL_DEFINE_PROGRAM (coloring,
-                       "/org/gtk/libgsk/gl/coloring.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("coloring.glsl")),
                        GSK_GL_NO_UNIFORMS)
 
 GSK_GL_DEFINE_PROGRAM (color_matrix,
-                       "/org/gtk/libgsk/gl/color_matrix.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("color_matrix.glsl")),
                        GSK_GL_ADD_UNIFORM (1, COLOR_MATRIX_COLOR_MATRIX, u_color_matrix)
                        GSK_GL_ADD_UNIFORM (2, COLOR_MATRIX_COLOR_OFFSET, u_color_offset))
 
 GSK_GL_DEFINE_PROGRAM (conic_gradient,
-                       "/org/gtk/libgsk/gl/conic_gradient.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("conic_gradient.glsl")),
                        GSK_GL_ADD_UNIFORM (1, CONIC_GRADIENT_COLOR_STOPS, u_color_stops)
                        GSK_GL_ADD_UNIFORM (2, CONIC_GRADIENT_NUM_COLOR_STOPS, u_num_color_stops)
                        GSK_GL_ADD_UNIFORM (3, CONIC_GRADIENT_GEOMETRY, u_geometry))
 
 GSK_GL_DEFINE_PROGRAM (cross_fade,
-                       "/org/gtk/libgsk/gl/cross_fade.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("cross_fade.glsl")),
                        GSK_GL_ADD_UNIFORM (1, CROSS_FADE_PROGRESS, u_progress)
                        GSK_GL_ADD_UNIFORM (2, CROSS_FADE_SOURCE2, u_source2))
 
 GSK_GL_DEFINE_PROGRAM (filled_border,
-                       "/org/gtk/libgsk/gl/filled_border.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("filled_border.glsl")),
                        GSK_GL_ADD_UNIFORM (1, FILLED_BORDER_WIDTHS, u_widths)
                        GSK_GL_ADD_UNIFORM (2, FILLED_BORDER_OUTLINE_RECT, u_outline_rect))
 
 GSK_GL_DEFINE_PROGRAM (inset_shadow,
-                       "/org/gtk/libgsk/gl/inset_shadow.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("inset_shadow.glsl")),
                        GSK_GL_ADD_UNIFORM (1, INSET_SHADOW_SPREAD, u_spread)
                        GSK_GL_ADD_UNIFORM (2, INSET_SHADOW_OFFSET, u_offset)
                        GSK_GL_ADD_UNIFORM (3, INSET_SHADOW_OUTLINE_RECT, u_outline_rect))
 
 GSK_GL_DEFINE_PROGRAM (linear_gradient,
-                       "/org/gtk/libgsk/gl/linear_gradient.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("linear_gradient.glsl")),
                        GSK_GL_ADD_UNIFORM (1, LINEAR_GRADIENT_COLOR_STOPS, u_color_stops)
                        GSK_GL_ADD_UNIFORM (2, LINEAR_GRADIENT_NUM_COLOR_STOPS, u_num_color_stops)
                        GSK_GL_ADD_UNIFORM (3, LINEAR_GRADIENT_POINTS, u_points)
                        GSK_GL_ADD_UNIFORM (4, LINEAR_GRADIENT_REPEAT, u_repeat))
 
 GSK_GL_DEFINE_PROGRAM (outset_shadow,
-                       "/org/gtk/libgsk/gl/outset_shadow.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("outset_shadow.glsl")),
                        GSK_GL_ADD_UNIFORM (1, OUTSET_SHADOW_OUTLINE_RECT, u_outline_rect))
 
 GSK_GL_DEFINE_PROGRAM (radial_gradient,
-                       "/org/gtk/libgsk/gl/radial_gradient.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("radial_gradient.glsl")),
                        GSK_GL_ADD_UNIFORM (1, RADIAL_GRADIENT_COLOR_STOPS, u_color_stops)
                        GSK_GL_ADD_UNIFORM (2, RADIAL_GRADIENT_NUM_COLOR_STOPS, u_num_color_stops)
                        GSK_GL_ADD_UNIFORM (3, RADIAL_GRADIENT_REPEAT, u_repeat)
@@ -73,12 +73,12 @@ GSK_GL_DEFINE_PROGRAM (radial_gradient,
                        GSK_GL_ADD_UNIFORM (5, RADIAL_GRADIENT_GEOMETRY, u_geometry))
 
 GSK_GL_DEFINE_PROGRAM (repeat,
-                       "/org/gtk/libgsk/gl/repeat.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("repeat.glsl")),
                        GSK_GL_ADD_UNIFORM (1, REPEAT_CHILD_BOUNDS, u_child_bounds)
                        GSK_GL_ADD_UNIFORM (2, REPEAT_TEXTURE_RECT, u_texture_rect))
 
 GSK_GL_DEFINE_PROGRAM (unblurred_outset_shadow,
-                       "/org/gtk/libgsk/gl/unblurred_outset_shadow.glsl",
+                       GSK_GL_SHADER_SINGLE (GSK_GL_SHADER_RESOURCE ("unblurred_outset_shadow.glsl")),
                        GSK_GL_ADD_UNIFORM (1, UNBLURRED_OUTSET_SHADOW_SPREAD, u_spread)
                        GSK_GL_ADD_UNIFORM (2, UNBLURRED_OUTSET_SHADOW_OFFSET, u_offset)
                        GSK_GL_ADD_UNIFORM (3, UNBLURRED_OUTSET_SHADOW_OUTLINE_RECT, u_outline_rect))

gsk/gl/gskglrenderjob.c

@@ -2512,7 +2512,9 @@ gsk_gl_render_job_visit_blurred_outset_shadow_node (GskGLRenderJob      *job,
       scaled_outline.corner[i].height *= scale_y;
     }
 
-  cached_tid = gsk_gl_shadow_library_lookup (job->driver->shadows, &scaled_outline, blur_radius);
+  cached_tid = gsk_gl_shadow_library_lookup (job->driver->shadows_library,
+                                             &scaled_outline,
+                                             blur_radius);
 
   if (cached_tid == 0)
     {
@@ -2574,7 +2576,7 @@ gsk_gl_render_job_visit_blurred_outset_shadow_node (GskGLRenderJob      *job,
                                            blur_radius * scale_x,
                                            blur_radius * scale_y);
 
-      gsk_gl_shadow_library_insert (job->driver->shadows,
+      gsk_gl_shadow_library_insert (job->driver->shadows_library,
                                     &scaled_outline,
                                     blur_radius,
                                     blurred_texture_id);
@@ -2858,58 +2860,6 @@ gsk_gl_render_job_visit_cross_fade_node (GskGLRenderJob      *job,
   gsk_gl_render_job_end_draw (job);
 }
 
-static gboolean
-is_non_branching (const GskRenderNode *node)
-{
-  switch ((int)gsk_render_node_get_node_type (node))
-    {
-    case GSK_COLOR_NODE:
-    case GSK_LINEAR_GRADIENT_NODE:
-    case GSK_REPEATING_LINEAR_GRADIENT_NODE:
-    case GSK_RADIAL_GRADIENT_NODE:
-    case GSK_REPEATING_RADIAL_GRADIENT_NODE:
-    case GSK_CONIC_GRADIENT_NODE:
-    case GSK_BORDER_NODE:
-    case GSK_TEXTURE_NODE:
-    case GSK_INSET_SHADOW_NODE:
-    case GSK_OUTSET_SHADOW_NODE:
-    case GSK_TEXT_NODE:
-    case GSK_CAIRO_NODE:
-      return TRUE;
-
-    case GSK_TRANSFORM_NODE:
-      return is_non_branching (gsk_transform_node_get_child (node));
-
-    case GSK_OPACITY_NODE:
-      return is_non_branching (gsk_opacity_node_get_child (node));
-
-    case GSK_COLOR_MATRIX_NODE:
-      return is_non_branching (gsk_color_matrix_node_get_child (node));
-
-    case GSK_CLIP_NODE:
-      return is_non_branching (gsk_clip_node_get_child (node));
-
-    case GSK_ROUNDED_CLIP_NODE:
-      return is_non_branching (gsk_rounded_clip_node_get_child (node));
-
-    case GSK_SHADOW_NODE:
-      return is_non_branching (gsk_shadow_node_get_child (node));
-
-    case GSK_BLUR_NODE:
-      return is_non_branching (gsk_shadow_node_get_child (node));
-
-    case GSK_DEBUG_NODE:
-      return is_non_branching (gsk_debug_node_get_child (node));
-
-    case GSK_CONTAINER_NODE:
-      return gsk_container_node_get_n_children (node) == 1 &&
-             is_non_branching (gsk_container_node_get_child (node, 0));
-
-    default:
-      return FALSE;
-    }
-}
-
 static inline void
 gsk_gl_render_job_visit_opacity_node (GskGLRenderJob      *job,
                                       const GskRenderNode *node)
@@ -2922,11 +2872,7 @@ gsk_gl_render_job_visit_opacity_node (GskGLRenderJob      *job,
     {
       float prev_alpha = gsk_gl_render_job_set_alpha (job, new_alpha);
 
-      /* Handle a few easy cases without offscreen. We bail out
-       * as soon as we see nodes with multiple children - in theory,
-       * we would only need offscreens for overlapping children.
-       */
-      if (is_non_branching (child))
+      if (!gsk_render_node_use_offscreen_for_opacity (child))
         {
           gsk_gl_render_job_visit_node (job, child);
           gsk_gl_render_job_set_alpha (job, prev_alpha);
@@ -2996,7 +2942,7 @@ gsk_gl_render_job_visit_text_node (GskGLRenderJob      *job,
   guint num_glyphs = gsk_text_node_get_num_glyphs (node);
   float x = offset->x + job->offset_x;
   float y = offset->y + job->offset_y;
-  GskGLGlyphLibrary *library = job->driver->glyphs;
+  GskGLGlyphLibrary *library = job->driver->glyphs_library;
   GskGLCommandBatch *batch;
   int x_position = 0;
   GskGLGlyphKey lookup;
@@ -3499,14 +3445,14 @@ gsk_gl_render_job_upload_texture (GskGLRenderJob       *job,
                                   GdkTexture           *texture,
                                   GskGLRenderOffscreen *offscreen)
 {
-  if (gsk_gl_texture_library_can_cache ((GskGLTextureLibrary *)job->driver->icons,
+  if (gsk_gl_texture_library_can_cache ((GskGLTextureLibrary *)job->driver->icons_library,
                                         texture->width,
                                         texture->height) &&
       !GDK_IS_GL_TEXTURE (texture))
     {
       const GskGLIconData *icon_data;
 
-      gsk_gl_icon_library_lookup_or_add (job->driver->icons, texture, &icon_data);
+      gsk_gl_icon_library_lookup_or_add (job->driver->icons_library, texture, &icon_data);
       offscreen->texture_id = GSK_GL_TEXTURE_ATLAS_ENTRY_TEXTURE (icon_data);
       memcpy (&offscreen->area, &icon_data->entry.area, sizeof offscreen->area);
     }
@@ -3824,6 +3770,11 @@ gsk_gl_render_job_visit_node (GskGLRenderJob      *job,
       gsk_gl_render_job_visit_as_fallback (job, node);
     break;
 
+    case GSK_FILL_NODE:
+    case GSK_STROKE_NODE:
+      gsk_gl_render_job_visit_as_fallback (job, node);
+    break;
+
     case GSK_NOT_A_RENDER_NODE:
     default:
       g_assert_not_reached ();
@@ -3869,7 +3820,6 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
 
   filter = offscreen->linear_filter ? GL_LINEAR : GL_NEAREST;
 
-  /* Check if we've already cached the drawn texture. */
   key.pointer = node;
   key.pointer_is_child = TRUE; /* Don't conflict with the child using the cache too */
   key.parent_rect = *offscreen->bounds;
@@ -3877,61 +3827,111 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
   key.scale_y = job->scale_y;
   key.filter = filter;
 
-  cached_id = gsk_gl_driver_lookup_texture (job->driver, &key);
+  float offset_x = job->offset_x;
+  float offset_y = job->offset_y;
+  gboolean flipped_x = job->scale_x < 0;
+  gboolean flipped_y = job->scale_y < 0;
+  graphene_rect_t viewport;
 
-  if (cached_id != 0)
+  if (flipped_x || flipped_y)
     {
-      offscreen->texture_id = cached_id;
-      init_full_texture_region (offscreen);
-      /* We didn't render it offscreen, but hand out an offscreen texture id */
-      offscreen->was_offscreen = TRUE;
-      return TRUE;
+      GskTransform *transform = gsk_transform_scale (NULL,
+                                                     flipped_x ? -1 : 1,
+                                                     flipped_y ? -1 : 1);
+      gsk_gl_render_job_push_modelview (job, transform);
     }
 
-  float scaled_width;
-  float scaled_height;
-  float downscale_x = 1;
-  float downscale_y = 1;
+  gsk_gl_render_job_transform_bounds (job, offscreen->bounds, &viewport);
 
-  g_assert (job->command_queue->max_texture_size > 0);
+  float aligned_x = floorf (viewport.origin.x);
+  float padding_left = viewport.origin.x - aligned_x;
+  float aligned_width = ceilf (viewport.size.width + padding_left);
+  float padding_right = aligned_width - viewport.size.width - padding_left;
+
+  float aligned_y = floorf (viewport.origin.y);
+  float padding_top = viewport.origin.y - aligned_y;
+  float aligned_height = ceilf (viewport.size.height + padding_top);
+  float padding_bottom = aligned_height - viewport.size.height - padding_top;
 
   /* Tweak the scale factor so that the required texture doesn't
    * exceed the max texture limit. This will render with a lower
    * resolution, but this is better than clipping.
    */
-  {
-    int max_texture_size = job->command_queue->max_texture_size;
 
-    scaled_width = ceilf (offscreen->bounds->size.width * fabs (job->scale_x));
-    if (scaled_width > max_texture_size)
-      {
-        downscale_x = (float)max_texture_size / scaled_width;
-        scaled_width = max_texture_size;
-      }
-    if (job->scale_x < 0)
-      downscale_x = -downscale_x;
+  g_assert (job->command_queue->max_texture_size > 0);
 
-    scaled_height = ceilf (offscreen->bounds->size.height * fabs (job->scale_y));
-    if (scaled_height > max_texture_size)
-      {
-        downscale_y = (float)max_texture_size / scaled_height;
-        scaled_height = max_texture_size;
-      }
-    if (job->scale_y < 0)
-      downscale_y = -downscale_y;
-  }
+  float downscale_x = 1;
+  float downscale_y = 1;
+  int texture_width;
+  int texture_height;
+  int max_texture_size = job->command_queue->max_texture_size;
+
+  if (aligned_width > max_texture_size)
+    downscale_x = (float)max_texture_size / viewport.size.width;
+
+  if (aligned_height > max_texture_size)
+    downscale_y = (float)max_texture_size / viewport.size.height;
+
+  if (downscale_x != 1 || downscale_y != 1)
+    {
+      GskTransform *transform = gsk_transform_scale (NULL, downscale_x, downscale_y);
+      gsk_gl_render_job_push_modelview (job, transform);
+      gsk_gl_render_job_transform_bounds (job, offscreen->bounds, &viewport);
+    }
+
+  if (downscale_x == 1)
+    {
+      viewport.origin.x = aligned_x;
+      viewport.size.width = aligned_width;
+      offscreen->area.x = padding_left / aligned_width;
+      offscreen->area.x2 = 1.0f - (padding_right / aligned_width);
+      texture_width = aligned_width;
+    }
+  else
+    {
+      offscreen->area.x = 0;
+      offscreen->area.x2 = 1;
+      texture_width = max_texture_size;
+    }
+
+  if (downscale_y == 1)
+    {
+      viewport.origin.y = aligned_y;
+      viewport.size.height = aligned_height;
+      offscreen->area.y = padding_bottom / aligned_height;
+      offscreen->area.y2 = 1.0f - padding_top / aligned_height;
+      texture_height = aligned_height;
+    }
+   else
+    {
+      offscreen->area.y = 0;
+      offscreen->area.y2 = 1;
+      texture_height = max_texture_size;
+    }
+
+  /* Check if we've already cached the drawn texture. */
+  cached_id = gsk_gl_driver_lookup_texture (job->driver, &key);
+
+  if (cached_id != 0)
+    {
+      if (downscale_x != 1 || downscale_y != 1)
+        gsk_gl_render_job_pop_modelview (job);
+      if (flipped_x || flipped_y)
+        gsk_gl_render_job_pop_modelview (job);
+      offscreen->texture_id = cached_id;
+      /* We didn't render it offscreen, but hand out an offscreen texture id */
+      offscreen->was_offscreen = TRUE;
+      return TRUE;
+    }
 
   GskGLRenderTarget *render_target;
   graphene_matrix_t prev_projection;
   graphene_rect_t prev_viewport;
-  graphene_rect_t viewport;
-  float offset_x = job->offset_x;
-  float offset_y = job->offset_y;
   float prev_alpha;
   guint prev_fbo;
 
   if (!gsk_gl_driver_create_render_target (job->driver,
-                                           scaled_width, scaled_height,
+                                           texture_width, texture_height,
                                            get_target_format (job, node),
                                            filter, filter,
                                            &render_target))
@@ -3953,19 +3953,6 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
                                           render_target->framebuffer_id);
     }
 
-  if (downscale_x != 1 || downscale_y != 1)
-    {
-      GskTransform *transform = gsk_transform_scale (NULL, downscale_x, downscale_y);
-      gsk_gl_render_job_push_modelview (job, transform);
-      gsk_transform_unref (transform);
-    }
-
-  gsk_gl_render_job_transform_bounds (job, offscreen->bounds, &viewport);
-  /* Code above will scale the size with the scale we use in the render ops,
-   * but for the viewport size, we need our own size limited by the texture size */
-  viewport.size.width = scaled_width;
-  viewport.size.height = scaled_height;
-
   gsk_gl_render_job_set_viewport (job, &viewport, &prev_viewport);
   gsk_gl_render_job_set_projection_from_rect (job, &job->viewport, &prev_projection);
   prev_alpha = gsk_gl_render_job_set_alpha (job, 1.0f);
@@ -3983,6 +3970,10 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
 
   if (downscale_x != 1 || downscale_y != 1)
     gsk_gl_render_job_pop_modelview (job);
+
+  if (flipped_x || flipped_y)
+    gsk_gl_render_job_pop_modelview (job);
+
   gsk_gl_render_job_set_viewport (job, &prev_viewport, NULL);
   gsk_gl_render_job_set_projection (job, &prev_projection);
   gsk_gl_render_job_set_alpha (job, prev_alpha);
@@ -3996,8 +3987,6 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
                                                                render_target,
                                                                FALSE);
 
-  init_full_texture_region (offscreen);
-
   if (!offscreen->do_not_cache)
     gsk_gl_driver_cache_texture (job->driver, &key, offscreen->texture_id);
 

gsk/gl/gskglshadowlibrary.c

@@ -29,9 +29,9 @@
 
 struct _GskGLShadowLibrary
 {
-  GObject        parent_instance;
+  GObject      parent_instance;
   GskGLDriver *driver;
-  GArray        *shadows;
+  GArray      *shadows;
 };
 
 typedef struct _Shadow

gsk/gl/gskgltexturelibrary.c

@@ -27,7 +27,10 @@
 #include "gskgldriverprivate.h"
 #include "gskgltexturelibraryprivate.h"
 
-#define MAX_FRAME_AGE 60
+#define DEFAULT_MAX_FRAME_AGE 60
+#define DEFAULT_ATLAS_WIDTH 512
+#define DEFAULT_ATLAS_HEIGHT 512
+#define MAX_OLD_RATIO 0.5
 
 G_DEFINE_ABSTRACT_TYPE (GskGLTextureLibrary, gsk_gl_texture_library, G_TYPE_OBJECT)
 
@@ -39,6 +42,149 @@ enum {
 
 static GParamSpec *properties [N_PROPS];
 
+static void
+gsk_gl_texture_atlas_free (GskGLTextureAtlas *atlas)
+{
+  if (atlas->texture_id != 0)
+    {
+      glDeleteTextures (1, &atlas->texture_id);
+      atlas->texture_id = 0;
+    }
+
+  g_clear_pointer (&atlas->nodes, g_free);
+  g_slice_free (GskGLTextureAtlas, atlas);
+}
+
+static gboolean
+gsk_gl_texture_library_real_compact (GskGLTextureLibrary *self,
+                                     gint64               frame_id)
+{
+  GPtrArray *removed = NULL;
+  gboolean ret = FALSE;
+  gboolean periodic_scan;
+
+  g_assert (GSK_IS_GL_TEXTURE_LIBRARY (self));
+
+  periodic_scan = (self->max_frame_age > 0 &&
+                   (frame_id % self->max_frame_age) == 0);
+
+  for (guint i = self->atlases->len; i > 0; i--)
+    {
+      GskGLTextureAtlas *atlas = g_ptr_array_index (self->atlases, i - 1);
+
+      if (gsk_gl_texture_atlas_get_unused_ratio (atlas) > MAX_OLD_RATIO)
+        {
+          GSK_NOTE (GLYPH_CACHE,
+                    g_message ("Dropping atlas %d (%g.2%% old)", i,
+                               100.0 * gsk_gl_texture_atlas_get_unused_ratio (atlas)));
+          if (removed == NULL)
+            removed = g_ptr_array_new_with_free_func ((GDestroyNotify)gsk_gl_texture_atlas_free);
+          g_ptr_array_add (removed, g_ptr_array_steal_index (self->atlases, i - 1));
+        }
+    }
+
+  if (periodic_scan || removed != NULL)
+    {
+      GskGLTextureAtlasEntry *entry;
+      GHashTableIter iter;
+      guint dropped = 0;
+      guint atlased = 0;
+
+      g_hash_table_iter_init (&iter, self->hash_table);
+      while (g_hash_table_iter_next (&iter, NULL, (gpointer *)&entry))
+        {
+          if (entry->is_atlased)
+            {
+              if (removed && g_ptr_array_find (removed, entry->atlas, NULL))
+                {
+                  g_hash_table_iter_remove (&iter);
+                  dropped++;
+                }
+              else if (periodic_scan)
+                {
+                  gsk_gl_texture_atlas_entry_mark_unused (entry);
+                  entry->accessed = FALSE;
+                  if (entry->is_atlased)
+                    atlased++;
+                }
+            }
+          else
+            {
+              if (!entry->accessed)
+                {
+                  gsk_gl_driver_release_texture (self->driver, entry->texture);
+                  g_hash_table_iter_remove (&iter);
+                  dropped++;
+                }
+
+              if (periodic_scan)
+                  entry->accessed = FALSE;
+            }
+        }
+
+      GSK_NOTE (GLYPH_CACHE, g_message ("%s: Dropped %d individual items",
+                                        G_OBJECT_TYPE_NAME (self),
+                                        dropped);
+                             g_message ("%s: %d items cached (%d atlased, %d individually)",
+                                        G_OBJECT_TYPE_NAME (self),
+                                        g_hash_table_size (self->hash_table),
+                                        atlased,
+                                        g_hash_table_size (self->hash_table) - atlased));
+
+      if (dropped > 0)
+        gsk_gl_texture_library_clear_cache (self);
+
+      ret = TRUE;
+
+      g_clear_pointer (&removed, g_ptr_array_unref);
+    }
+
+  GSK_NOTE (GLYPH_CACHE, {
+    static gint64 last_message;
+    gint64 now = g_get_monotonic_time ();
+    if (now - last_message > G_USEC_PER_SEC)
+      {
+        last_message = now;
+        g_message ("%s contains %d atlases",
+                   G_OBJECT_TYPE_NAME (self),
+                   self->atlases->len);
+      }
+  });
+
+  return ret;
+}
+
+static gboolean
+gsk_gl_texture_library_real_allocate (GskGLTextureLibrary *self,
+                                      GskGLTextureAtlas   *atlas,
+                                      int                  width,
+                                      int                  height,
+                                      int                 *out_x,
+                                      int                 *out_y)
+{
+  stbrp_rect rect;
+
+  g_assert (GSK_IS_GL_TEXTURE_LIBRARY (self));
+  g_assert (atlas != NULL);
+  g_assert (width > 0);
+  g_assert (height > 0);
+  g_assert (out_x != NULL);
+  g_assert (out_y != NULL);
+
+  rect.w = width;
+  rect.h = height;
+
+  stbrp_pack_rects (&atlas->context, &rect, 1);
+
+  if (rect.was_packed)
+    {
+      *out_x = rect.x;
+      *out_y = rect.y;
+    }
+
+  return rect.was_packed;
+}
+
 static void
 gsk_gl_texture_library_constructed (GObject *object)
 {
@@ -52,6 +198,7 @@ gsk_gl_texture_library_dispose (GObject *object)
 {
   GskGLTextureLibrary *self = (GskGLTextureLibrary *)object;
 
+  g_clear_pointer (&self->atlases, g_ptr_array_unref);
   g_clear_object (&self->driver);
 
   G_OBJECT_CLASS (gsk_gl_texture_library_parent_class)->dispose (object);
@@ -105,6 +252,9 @@ gsk_gl_texture_library_class_init (GskGLTextureLibraryClass *klass)
   object_class->get_property = gsk_gl_texture_library_get_property;
   object_class->set_property = gsk_gl_texture_library_set_property;
 
+  klass->compact = gsk_gl_texture_library_real_compact;
+  klass->allocate = gsk_gl_texture_library_real_allocate;
+
   properties [PROP_DRIVER] =
     g_param_spec_object ("driver",
                          "Driver",
@@ -118,6 +268,10 @@ gsk_gl_texture_library_class_init (GskGLTextureLibraryClass *klass)
 static void
 gsk_gl_texture_library_init (GskGLTextureLibrary *self)
 {
+  self->max_frame_age = DEFAULT_MAX_FRAME_AGE;
+  self->atlas_width = DEFAULT_ATLAS_WIDTH;
+  self->atlas_height = DEFAULT_ATLAS_HEIGHT;
+  self->atlases = g_ptr_array_new_with_free_func ((GDestroyNotify)gsk_gl_texture_atlas_free);
 }
 
 void
@@ -136,78 +290,14 @@ gsk_gl_texture_library_set_funcs (GskGLTextureLibrary *self,
 
 void
 gsk_gl_texture_library_begin_frame (GskGLTextureLibrary *self,
-                                    gint64               frame_id,
-                                    GPtrArray            *removed_atlases)
+                                    gint64               frame_id)
 {
-  GHashTableIter iter;
-
   g_return_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self));
 
+  gsk_gl_texture_library_compact (self, frame_id);
+
   if (GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->begin_frame)
-    GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->begin_frame (self, frame_id, removed_atlases);
-
-  if (removed_atlases != NULL)
-    {
-      GskGLTextureAtlasEntry *entry;
-      guint dropped = 0;
-
-      g_hash_table_iter_init (&iter, self->hash_table);
-      while (g_hash_table_iter_next (&iter, NULL, (gpointer *)&entry))
-        {
-          if (entry->is_atlased)
-            {
-              for (guint i = 0; i < removed_atlases->len; i++)
-                {
-                  GskGLTextureAtlas *atlas = g_ptr_array_index (removed_atlases, i);
-
-                  if (atlas == entry->atlas)
-                    {
-                      g_hash_table_iter_remove (&iter);
-                      dropped++;
-                      break;
-                    }
-                }
-            }
-        }
-
-      GSK_NOTE (GLYPH_CACHE,
-                if (dropped > 0)
-                  g_message ("%s: Dropped %d items",
-                             G_OBJECT_TYPE_NAME (self), dropped));
-    }
-
-  if (frame_id % MAX_FRAME_AGE == 0)
-    {
-      GskGLTextureAtlasEntry *entry;
-      int atlased = 0;
-      int dropped = 0;
-
-      g_hash_table_iter_init (&iter, self->hash_table);
-      while (g_hash_table_iter_next (&iter, NULL, (gpointer *)&entry))
-        {
-          if (!entry->is_atlased && !entry->accessed)
-            {
-              gsk_gl_driver_release_texture (self->driver, entry->texture);
-              g_hash_table_iter_remove (&iter);
-              dropped++;
-              continue;
-            }
-
-          gsk_gl_texture_atlas_entry_mark_unused (entry);
-          entry->accessed = FALSE;
-          if (entry->is_atlased)
-            atlased++;
-        }
-
-      GSK_NOTE (GLYPH_CACHE, g_message ("%s: Dropped %d individual items",
-                                        G_OBJECT_TYPE_NAME (self),
-                                        dropped);
-                             g_message ("%s: %d items cached (%d atlased, %d individually)",
-                                        G_OBJECT_TYPE_NAME (self),
-                                        g_hash_table_size (self->hash_table),
-                                        atlased,
-                                        g_hash_table_size (self->hash_table) - atlased));
-    }
+    GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->begin_frame (self, frame_id);
 }
 
 static GskGLTexture *
@@ -234,90 +324,29 @@ gsk_gl_texture_library_pack_one (GskGLTextureLibrary *self,
   return texture;
 }
 
-static inline gboolean
-gsk_gl_texture_atlas_pack (GskGLTextureAtlas *self,
-                           int                width,
-                           int                height,
-                           int               *out_x,
-                           int               *out_y)
-{
-  stbrp_rect rect;
-
-  rect.w = width;
-  rect.h = height;
-
-  stbrp_pack_rects (&self->context, &rect, 1);
-
-  if (rect.was_packed)
-    {
-      *out_x = rect.x;
-      *out_y = rect.y;
-    }
-
-  return rect.was_packed;
-}
-
 static void
-gsk_gl_texture_atlas_initialize (GskGLDriver       *driver,
-                                 GskGLTextureAtlas *atlas)
-{
-  /* Insert a single pixel at 0,0 for use in coloring */
-
-  gboolean packed G_GNUC_UNUSED;
-  int x, y;
-  guint gl_format;
-  guint gl_type;
-  guint8 pixel_data[4 * 3 * 3];
-
-  gdk_gl_context_push_debug_group_printf (gdk_gl_context_get_current (),
-                                          "Initializing Atlas");
-
-  packed = gsk_gl_texture_atlas_pack (atlas, 3, 3, &x, &y);
-  g_assert (packed);
-  g_assert (x == 0 && y == 0);
-
-  memset (pixel_data, 255, sizeof pixel_data);
-
-  if (gdk_gl_context_get_use_es (gdk_gl_context_get_current ()))
-    {
-      gl_format = GL_RGBA;
-      gl_type = GL_UNSIGNED_BYTE;
-    }
-  else
-    {
-      gl_format = GL_BGRA;
-      gl_type = GL_UNSIGNED_INT_8_8_8_8_REV;
-    }
-
-  glBindTexture (GL_TEXTURE_2D, atlas->texture_id);
-
-  glTexSubImage2D (GL_TEXTURE_2D, 0,
-                   0, 0,
-                   3, 3,
-                   gl_format, gl_type,
-                   pixel_data);
-
-  gdk_gl_context_pop_debug_group (gdk_gl_context_get_current ());
-
-  driver->command_queue->n_uploads++;
-}
-
-static void
-gsk_gl_texture_atlases_pack (GskGLDriver        *driver,
-                             int                 width,
-                             int                 height,
-                             GskGLTextureAtlas **out_atlas,
-                             int                *out_x,
-                             int                *out_y)
+gsk_gl_texture_library_pack_any_atlas (GskGLTextureLibrary  *self,
+                                       int                   width,
+                                       int                   height,
+                                       GskGLTextureAtlas   **out_atlas,
+                                       int                  *out_x,
+                                       int                  *out_y)
 {
   GskGLTextureAtlas *atlas = NULL;
   int x, y;
 
-  for (guint i = 0; i < driver->atlases->len; i++)
-    {
-      atlas = g_ptr_array_index (driver->atlases, i);
+  g_assert (GSK_IS_GL_TEXTURE_LIBRARY (self));
+  g_assert (width > 0);
+  g_assert (height > 0);
+  g_assert (out_atlas != NULL);
+  g_assert (out_x != NULL);
+  g_assert (out_y != NULL);
 
-      if (gsk_gl_texture_atlas_pack (atlas, width, height, &x, &y))
+  for (guint i = 0; i < self->atlases->len; i++)
+    {
+      atlas = g_ptr_array_index (self->atlases, i);
+
+      if (gsk_gl_texture_library_allocate (self, atlas, width, height, &x, &y))
         break;
 
       atlas = NULL;
@@ -326,12 +355,10 @@ gsk_gl_texture_atlases_pack (GskGLDriver        *driver,
   if (atlas == NULL)
     {
       /* No atlas has enough space, so create a new one... */
-      atlas = gsk_gl_driver_create_atlas (driver);
-
-      gsk_gl_texture_atlas_initialize (driver, atlas);
+      atlas = gsk_gl_texture_library_acquire_atlas (self);
 
       /* Pack it onto that one, which surely has enough space... */
-      if (!gsk_gl_texture_atlas_pack (atlas, width, height, &x, &y))
+      if (!gsk_gl_texture_library_allocate (self, atlas, width, height, &x, &y))
         g_assert_not_reached ();
     }
 
@@ -380,17 +407,19 @@ gsk_gl_texture_library_pack (GskGLTextureLibrary *self,
       *out_packed_x = 0;
       *out_packed_y = 0;
     }
-  else if (width <= self->max_entry_size && height <= self->max_entry_size)
+  else if (self->max_entry_size == 0 ||
+           (width <= self->max_entry_size &&
+            height <= self->max_entry_size))
     {
       int packed_x;
       int packed_y;
 
-      gsk_gl_texture_atlases_pack (self->driver,
-                                   padding + width + padding,
-                                   padding + height + padding,
-                                   &atlas,
-                                   &packed_x,
-                                   &packed_y);
+      gsk_gl_texture_library_pack_any_atlas (self,
+                                             padding + width + padding,
+                                             padding + height + padding,
+                                             &atlas,
+                                             &packed_x,
+                                             &packed_y);
 
       entry->atlas = atlas;
       entry->is_atlased = TRUE;
@@ -424,3 +453,134 @@ gsk_gl_texture_library_pack (GskGLTextureLibrary *self,
 
   return entry;
 }
+
+/*
+ * gsk_gl_texture_library_clear_cache:
+ *
+ * Clear the front cache if the texture library is using one. For
+ * example the glyph cache would drop it's front cache to force
+ * next lookups to fall through to the GHashTable key lookup.
+ */
+void
+gsk_gl_texture_library_clear_cache (GskGLTextureLibrary *self)
+{
+  g_return_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self));
+
+  if (GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->clear_cache)
+    GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->clear_cache (self);
+}
+
+/*
+ * gsk_gl_texture_library_compact:
+ *
+ * Requests that the texture library compact it's altases. That
+ * generally means to traverse them to look for unused pixels over
+ * a certain threshold and release them if necessary.
+ *
+ * Returns: %TRUE if any compaction occurred.
+ */
+gboolean
+gsk_gl_texture_library_compact (GskGLTextureLibrary *self,
+                                gint64               frame_id)
+{
+  g_return_val_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self), FALSE);
+
+  if (GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->compact)
+    return GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->compact (self, frame_id);
+
+  return FALSE;
+}
+
+void
+gsk_gl_texture_library_reset (GskGLTextureLibrary *self)
+{
+  g_return_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self));
+
+  gsk_gl_texture_library_clear_cache (self);
+
+  g_hash_table_remove_all (self->hash_table);
+
+  if (self->atlases->len)
+    g_ptr_array_remove_range (self->atlases, 0, self->atlases->len);
+}
+
+void
+gsk_gl_texture_library_set_atlas_size (GskGLTextureLibrary *self,
+                                       int                  width,
+                                       int                  height)
+{
+  g_return_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self));
+
+  if (width <= 0)
+    width = DEFAULT_ATLAS_WIDTH;
+
+  if (height <= 0)
+    height = DEFAULT_ATLAS_HEIGHT;
+
+  self->atlas_height = height;
+  self->atlas_width = width;
+
+  gsk_gl_texture_library_reset (self);
+}
+
+/*
+ * gsk_gl_texture_library_acquire_atlas:
+ *
+ * Allocates a new texture atlas based on the current size
+ * and format requirements.
+ */
+GskGLTextureAtlas *
+gsk_gl_texture_library_acquire_atlas (GskGLTextureLibrary *self)
+{
+  GskGLTextureAtlas *atlas;
+
+  g_return_val_if_fail (GSK_IS_GL_TEXTURE_LIBRARY (self), NULL);
+  g_return_val_if_fail (GSK_IS_GL_DRIVER (self->driver), NULL);
+  g_return_val_if_fail (GSK_IS_GL_COMMAND_QUEUE (self->driver->command_queue), NULL);
+  g_return_val_if_fail (self->atlas_width > 0, NULL);
+  g_return_val_if_fail (self->atlas_height > 0, NULL);
+
+  atlas = g_slice_new0 (GskGLTextureAtlas);
+  atlas->width = self->atlas_width;
+  atlas->height = self->atlas_height;
+  /* TODO: We might want to change the strategy about the amount of
+   *       nodes here? stb_rect_pack.h says width is optimal. */
+  atlas->nodes = g_malloc0_n (atlas->width, sizeof (struct stbrp_node));
+  stbrp_init_target (&atlas->context, atlas->width, atlas->height, atlas->nodes, atlas->width);
+  atlas->texture_id = gsk_gl_command_queue_create_texture (self->driver->command_queue,
+                                                           atlas->width,
+                                                           atlas->height,
+                                                           GL_RGBA8,
+                                                           GL_LINEAR,
+                                                           GL_LINEAR);
+
+  gdk_gl_context_label_object_printf (gdk_gl_context_get_current (),
+                                      GL_TEXTURE, atlas->texture_id,
+                                      "Texture atlas %d",
+                                      atlas->texture_id);
+
+  g_ptr_array_add (self->atlases, atlas);
+
+  if (GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->init_atlas)
+    GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->init_atlas (self, atlas);
+
+  return atlas;
+}
+
+gboolean
+gsk_gl_texture_library_allocate (GskGLTextureLibrary *self,
+                                 GskGLTextureAtlas   *atlas,
+                                 int                  width,
+                                 int                  height,
+                                 int                 *out_x,
+                                 int                 *out_y)
+{
+  g_assert (GSK_IS_GL_TEXTURE_LIBRARY (self));
+  g_assert (atlas != NULL);
+  g_assert (width > 0);
+  g_assert (height > 0);
+  g_assert (out_x != NULL);
+  g_assert (out_y != NULL);
+
+  return GSK_GL_TEXTURE_LIBRARY_GET_CLASS (self)->allocate (self, atlas, width, height, out_x, out_y);
+}

gsk/gl/gskgltexturelibraryprivate.h

@@ -50,7 +50,6 @@ typedef struct _GskGLTextureAtlas
    */
   int unused_pixels;
 
-  void *user_data;
 } GskGLTextureAtlas;
 
 typedef struct _GskGLTextureAtlasEntry
@@ -89,40 +88,67 @@ typedef struct _GskGLTextureAtlasEntry
 
 typedef struct _GskGLTextureLibrary
 {
-  GObject        parent_instance;
+  GObject      parent_instance;
   GskGLDriver *driver;
-  GHashTable    *hash_table;
-  guint          max_entry_size;
+  GPtrArray   *atlases;
+  GHashTable  *hash_table;
+  guint        max_entry_size;
+  guint        max_frame_age;
+  guint        atlas_width;
+  guint        atlas_height;
 } GskGLTextureLibrary;
 
 typedef struct _GskGLTextureLibraryClass
 {
   GObjectClass parent_class;
 
-  void (*begin_frame) (GskGLTextureLibrary *library,
-                       gint64               frame_id,
-                       GPtrArray           *removed_atlases);
+  void     (*begin_frame) (GskGLTextureLibrary *library,
+                           gint64               frame_id);
+  gboolean (*compact)     (GskGLTextureLibrary *library,
+                           gint64               frame_id);
+  void     (*clear_cache) (GskGLTextureLibrary *library);
+  void     (*init_atlas)  (GskGLTextureLibrary *library,
+                           GskGLTextureAtlas   *atlas);
+  gboolean (*allocate)    (GskGLTextureLibrary *library,
+                           GskGLTextureAtlas   *atlas,
+                           int                  width,
+                           int                  height,
+                           int                 *out_x,
+                           int                 *out_y);
 } GskGLTextureLibraryClass;
 
 G_DEFINE_AUTOPTR_CLEANUP_FUNC (GskGLTextureLibrary, g_object_unref)
 
-GType    gsk_gl_texture_library_get_type    (void) G_GNUC_CONST;
-void     gsk_gl_texture_library_set_funcs   (GskGLTextureLibrary *self,
-                                             GHashFunc            hash_func,
-                                             GEqualFunc           equal_func,
-                                             GDestroyNotify       key_destroy,
-                                             GDestroyNotify       value_destroy);
-void     gsk_gl_texture_library_begin_frame (GskGLTextureLibrary *self,
-                                             gint64               frame_id,
-                                             GPtrArray           *removed_atlases);
-gpointer gsk_gl_texture_library_pack        (GskGLTextureLibrary *self,
-                                             gpointer             key,
-                                             gsize                valuelen,
-                                             guint                width,
-                                             guint                height,
-                                             int                  padding,
-                                             guint               *out_packed_x,
-                                             guint               *out_packed_y);
+GType              gsk_gl_texture_library_get_type       (void) G_GNUC_CONST;
+gboolean           gsk_gl_texture_library_compact        (GskGLTextureLibrary *self,
+                                                          gint64               frame_id);
+void               gsk_gl_texture_library_clear_cache    (GskGLTextureLibrary *self);
+void               gsk_gl_texture_library_reset          (GskGLTextureLibrary *self);
+void               gsk_gl_texture_library_set_atlas_size (GskGLTextureLibrary *self,
+                                                          int                  width,
+                                                          int                  height);
+GskGLTextureAtlas *gsk_gl_texture_library_acquire_atlas  (GskGLTextureLibrary *self);
+void               gsk_gl_texture_library_set_funcs      (GskGLTextureLibrary *self,
+                                                          GHashFunc            hash_func,
+                                                          GEqualFunc           equal_func,
+                                                          GDestroyNotify       key_destroy,
+                                                          GDestroyNotify       value_destroy);
+void               gsk_gl_texture_library_begin_frame    (GskGLTextureLibrary *self,
+                                                          gint64               frame_id);
+gboolean           gsk_gl_texture_library_allocate       (GskGLTextureLibrary *self,
+                                                          GskGLTextureAtlas   *atlas,
+                                                          int                  width,
+                                                          int                  height,
+                                                          int                 *out_x,
+                                                          int                 *out_y);
+gpointer           gsk_gl_texture_library_pack           (GskGLTextureLibrary *self,
+                                                          gpointer             key,
+                                                          gsize                valuelen,
+                                                          guint                width,
+                                                          guint                height,
+                                                          int                  padding,
+                                                          guint               *out_packed_x,
+                                                          guint               *out_packed_y);
 
 static inline void
 gsk_gl_texture_atlas_mark_unused (GskGLTextureAtlas *self,

gsk/gsk-autocleanup.h

@@ -22,6 +22,8 @@
 
 #ifndef __GI_SCANNER__
 
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskPath, gsk_path_unref)
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskPathMeasure, gsk_path_measure_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskRenderer, g_object_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskRenderNode, gsk_render_node_unref)
 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskTransform, gsk_transform_unref)

gsk/gsk.h

@@ -21,11 +21,15 @@
 #define __GSK_H_INSIDE__
 
 #include <gsk/gskenums.h>
+#include <gsk/gskglshader.h>
+#include <gsk/gskpath.h>
+#include <gsk/gskpathbuilder.h>
+#include <gsk/gskpathmeasure.h>
 #include <gsk/gskrenderer.h>
 #include <gsk/gskrendernode.h>
 #include <gsk/gskroundedrect.h>
+#include <gsk/gskstroke.h>
 #include <gsk/gsktransform.h>
-#include <gsk/gskglshader.h>
 
 #include <gsk/gskcairorenderer.h>
 

gsk/gskboundingbox.c

@@ -0,0 +1,80 @@
+#include "config.h"
+
+#include "gskboundingboxprivate.h"
+
+GskBoundingBox *
+gsk_bounding_box_init (GskBoundingBox         *self,
+                       const graphene_point_t *a,
+                       const graphene_point_t *b)
+{
+  self->min.x = MIN (a->x, b->x);
+  self->min.y = MIN (a->y, b->y);
+  self->max.x = MAX (a->x, b->x);
+  self->max.y = MAX (a->y, b->y);
+  return self;
+}
+
+GskBoundingBox *
+gsk_bounding_box_init_copy (GskBoundingBox       *self,
+                            const GskBoundingBox *src)
+{
+  self->min = src->min;
+  self->max = src->max;
+  return self;
+}
+
+GskBoundingBox *
+gsk_bounding_box_init_from_rect (GskBoundingBox        *self,
+                                 const graphene_rect_t *bounds)
+{
+  self->min = bounds->origin;
+  self->max.x = bounds->origin.x + bounds->size.width;
+  self->max.y = bounds->origin.y + bounds->size.height;
+  return self;
+}
+
+void
+gsk_bounding_box_expand (GskBoundingBox         *self,
+                         const graphene_point_t *p)
+{
+  self->min.x = MIN (self->min.x, p->x);
+  self->min.y = MIN (self->min.y, p->y);
+  self->max.x = MAX (self->max.x, p->x);
+  self->max.y = MAX (self->max.y, p->y);
+}
+
+graphene_rect_t *
+gsk_bounding_box_to_rect (const GskBoundingBox  *self,
+                          graphene_rect_t       *rect)
+{
+  rect->origin = self->min;
+  rect->size.width = self->max.x - self->min.x;
+  rect->size.height = self->max.y - self->min.y;
+  return rect;
+}
+
+gboolean
+gsk_bounding_box_contains_point (const GskBoundingBox     *self,
+                                 const graphene_point_t *p)
+{
+  return self->min.x <= p->x && p->x <= self->max.x &&
+         self->min.y <= p->y && p->y <= self->max.y;
+}
+
+gboolean
+gsk_bounding_box_intersection (const GskBoundingBox *a,
+                               const GskBoundingBox *b,
+                               GskBoundingBox       *res)
+{
+  graphene_point_t min, max;
+
+  min.x = MAX (a->min.x, b->min.x);
+  min.y = MAX (a->min.y, b->min.y);
+  max.x = MIN (a->max.x, b->max.x);
+  max.y = MIN (a->max.y, b->max.y);
+
+  if (res)
+    gsk_bounding_box_init (res, &min, &max);
+
+  return min.x <= max.x && min.y <= max.y;
+}

gsk/gskboundingboxprivate.h

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <gsk/gsktypes.h>
+
+G_BEGIN_DECLS
+
+typedef struct _GskBoundingBox GskBoundingBox;
+
+struct _GskBoundingBox {
+  graphene_point_t min;
+  graphene_point_t max;
+};
+
+GDK_AVAILABLE_IN_ALL
+GskBoundingBox * gsk_bounding_box_init (GskBoundingBox         *self,
+                                        const graphene_point_t *a,
+                                        const graphene_point_t *b);
+
+GDK_AVAILABLE_IN_ALL
+GskBoundingBox * gsk_bounding_box_init_copy (GskBoundingBox       *self,
+                                             const GskBoundingBox *src);
+
+GDK_AVAILABLE_IN_ALL
+GskBoundingBox * gsk_bounding_box_init_from_rect (GskBoundingBox        *self,
+                                                  const graphene_rect_t *bounds);
+
+GDK_AVAILABLE_IN_ALL
+void             gsk_bounding_box_expand (GskBoundingBox         *self,
+                                          const graphene_point_t *p);
+
+GDK_AVAILABLE_IN_ALL
+graphene_rect_t *gsk_bounding_box_to_rect        (const GskBoundingBox  *self,
+                                                  graphene_rect_t       *rect);
+
+GDK_AVAILABLE_IN_ALL
+gboolean         gsk_bounding_box_contains_point (const GskBoundingBox   *self,
+                                                  const graphene_point_t *p);
+
+GDK_AVAILABLE_IN_ALL
+gboolean         gsk_bounding_box_intersection (const GskBoundingBox *a,
+                                                const GskBoundingBox *b,
+                                                GskBoundingBox       *res);
+
+G_END_DECLS

gsk/gskcontourprivate.h

@@ -0,0 +1,133 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_CONTOUR_PRIVATE_H__
+#define __GSK_CONTOUR_PRIVATE_H__
+
+#include <gskpath.h>
+
+#include "gskpathopprivate.h"
+
+G_BEGIN_DECLS
+
+/* A path is flat if it contains no cubic or conic segments.
+ * A path is closed if all its contours end with a GSK_PATH_CLOSE
+ * operation.
+ */
+typedef enum
+{
+  GSK_PATH_FLAT,
+  GSK_PATH_CLOSED
+} GskPathFlags;
+
+typedef struct _GskContour GskContour;
+
+GskContour *            gsk_rect_contour_new                    (const graphene_rect_t  *rect);
+GskContour *            gsk_rounded_rect_contour_new            (const GskRoundedRect   *rounded_rect);
+GskContour *            gsk_circle_contour_new                  (const graphene_point_t *center,
+                                                                 float                   radius,
+                                                                 float                   start_angle,
+                                                                 float                   end_angle);
+GskContour *            gsk_standard_contour_new                (GskPathFlags            flags,
+                                                                 const graphene_point_t *points,
+                                                                 gsize                   n_points,
+                                                                 const gskpathop        *ops,
+                                                                 gsize                   n_ops,
+                                                                 gssize                  offset);
+
+void                    gsk_contour_copy                        (GskContour *            dest,
+                                                                 const GskContour       *src);
+GskContour *            gsk_contour_dup                         (const GskContour       *src);
+
+GskContour *            gsk_contour_reverse                     (const GskContour       *src);
+
+gsize                   gsk_contour_get_size                    (const GskContour       *self);
+GskPathFlags            gsk_contour_get_flags                   (const GskContour       *self);
+void                    gsk_contour_print                       (const GskContour       *self,
+                                                                 GString                *string);
+gboolean                gsk_contour_get_bounds                  (const GskContour       *self,
+                                                                 graphene_rect_t        *bounds);
+gpointer                gsk_contour_init_measure                (const GskContour       *self,
+                                                                 float                   tolerance,
+                                                                 float                  *out_length);
+void                    gsk_contour_free_measure                (const GskContour       *self,
+                                                                 gpointer                data);
+gboolean                gsk_contour_foreach                     (const GskContour       *self,
+                                                                 float                   tolerance,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+void                    gsk_contour_get_start_end               (const GskContour       *self,
+                                                                 graphene_point_t       *start,
+                                                                 graphene_point_t       *end);
+void                    gsk_contour_get_point                   (const GskContour       *self,
+                                                                 gpointer                measure_data,
+                                                                 float                   distance,
+                                                                 graphene_point_t       *pos,
+                                                                 graphene_vec2_t        *tangent);
+float                   gsk_contour_get_curvature               (const GskContour       *self,
+                                                                 gpointer                measure_data,
+                                                                 float                   distance,
+                                                                 graphene_point_t       *center);
+gboolean                gsk_contour_get_closest_point           (const GskContour       *self,
+                                                                 gpointer                measure_data,
+                                                                 float                   tolerance,
+                                                                 const graphene_point_t *point,
+                                                                 float                   threshold,
+                                                                 float                  *out_distance,
+                                                                 graphene_point_t       *out_pos,
+                                                                 float                  *out_offset,
+                                                                 graphene_vec2_t        *out_tangent);
+int                     gsk_contour_get_winding                 (const GskContour       *self,
+                                                                 gpointer                measure_data,
+                                                                 const graphene_point_t *point,
+                                                                 gboolean               *on_edge);
+void                    gsk_contour_add_segment                 (const GskContour       *self,
+                                                                 GskPathBuilder         *builder,
+                                                                 gpointer                measure_data,
+                                                                 gboolean                emit_move_to,
+                                                                 float                   start,
+                                                                 float                   end);
+gboolean                gsk_contour_get_stroke_bounds           (const GskContour       *self,
+                                                                 const GskStroke        *stroke,
+                                                                 graphene_rect_t        *bounds);
+void                    gsk_contour_add_stroke                  (const GskContour       *contour,
+                                                                 GskPathBuilder         *builder,
+                                                                 GskStroke              *stroke);
+void                    gsk_contour_default_add_stroke          (const GskContour       *contour,
+                                                                 GskPathBuilder         *builder,
+                                                                 GskStroke              *stroke);
+
+void                    gsk_contour_offset                      (const GskContour       *contour,
+                                                                 GskPathBuilder         *builder,
+                                                                 float                   distance,
+                                                                 GskLineJoin             line_join,
+                                                                 float                   miter_limit);
+void                    gsk_contour_default_offset              (const GskContour       *contour,
+                                                                 GskPathBuilder         *builder,
+                                                                 float                   distance,
+                                                                 GskLineJoin             line_join,
+                                                                 float                   miter_limit);
+
+gboolean                gsk_contour_is_convex                   (const GskContour       *contour);
+
+G_END_DECLS
+
+#endif /* __GSK_CONTOUR_PRIVATE_H__ */
+

gsk/gskconvexity.c

@@ -0,0 +1,286 @@
+#include "config.h"
+
+#include "gskconvexityprivate.h"
+#include "gskcontourprivate.h"
+
+typedef enum
+{
+  GSK_DIR_CHANGE_UNKNOWN,
+  GSK_DIR_CHANGE_LEFT,
+  GSK_DIR_CHANGE_RIGHT,
+  GSK_DIR_CHANGE_STRAIGHT,
+  GSK_DIR_CHANGE_REVERSE,
+  GSK_DIR_CHANGE_INVALID,
+} GskDirChange;
+
+typedef enum
+{
+  GSK_PATH_DIRECTION_UNKNOWN,
+  GSK_PATH_DIRECTION_CLOCKWISE,
+  GSK_PATH_DIRECTION_COUNTERCLOCKWISE,
+} GskPathDirection;
+
+typedef struct _GskConvexityChecker GskConvexityChecker;
+struct _GskConvexityChecker
+{
+  graphene_point_t first_point;
+  graphene_vec2_t first_vec;
+  graphene_point_t last_point;
+  graphene_vec2_t last_vec;
+  GskDirChange expected_direction;
+  GskPathDirection first_direction;
+  int reversals;
+  gboolean finite;
+  GskConvexity convexity;
+  int xsign;
+  int ysign;
+  int dx;
+  int dy;
+};
+
+static float
+cross_product (graphene_vec2_t *a,
+               graphene_vec2_t *b)
+{
+  float fa[2];
+  float fb[2];
+  graphene_vec2_to_float (a, fa);
+  graphene_vec2_to_float (b, fb);
+  return fa[0] * fb[1] - fa[1] * fb[0];
+}
+
+static GskDirChange
+direction_change (GskConvexityChecker    *c,
+                  graphene_vec2_t *v)
+{
+  float cross = cross_product (&(c->last_vec), v);
+  if (!finite (cross))
+    return GSK_DIR_CHANGE_UNKNOWN;
+
+  if (cross == 0)
+    return graphene_vec2_dot (&(c->last_vec), v) < 0
+           ? GSK_DIR_CHANGE_REVERSE
+           : GSK_DIR_CHANGE_STRAIGHT;
+
+  return cross > 0
+         ? GSK_DIR_CHANGE_RIGHT
+         : GSK_DIR_CHANGE_LEFT;
+}
+
+static gboolean
+add_vec (GskConvexityChecker *c,
+         graphene_vec2_t     *v)
+{
+  GskDirChange dir;
+  int sign;
+
+  dir = direction_change (c, v);
+  switch (dir)
+    {
+    case GSK_DIR_CHANGE_LEFT:
+    case GSK_DIR_CHANGE_RIGHT:
+      if (c->expected_direction == GSK_DIR_CHANGE_INVALID)
+        {
+          c->expected_direction = dir;
+          c->first_direction = (dir == GSK_DIR_CHANGE_RIGHT)
+                               ? GSK_PATH_DIRECTION_CLOCKWISE
+                               : GSK_PATH_DIRECTION_COUNTERCLOCKWISE;
+        }
+      else if (c->expected_direction != dir)
+        {
+          c->first_direction = GSK_PATH_DIRECTION_UNKNOWN;
+          c->convexity = GSK_CONVEXITY_CONCAVE;
+          return FALSE;
+        }
+      graphene_vec2_init_from_vec2 (&c->last_vec, v);
+      break;
+
+    case GSK_DIR_CHANGE_STRAIGHT:
+      break;
+
+    case GSK_DIR_CHANGE_REVERSE:
+      graphene_vec2_init_from_vec2 (&c->last_vec, v);
+      c->reversals++;
+      if (c->reversals > 2)
+        c->convexity = GSK_CONVEXITY_CONCAVE;
+      return c->reversals < 3;
+
+    case GSK_DIR_CHANGE_UNKNOWN:
+      c->finite = FALSE;
+      return FALSE;
+
+    case GSK_DIR_CHANGE_INVALID:
+    default:
+      g_assert_not_reached ();
+    }
+
+  if (graphene_vec2_get_x (v) > 0)
+    sign = 1;
+  else if (graphene_vec2_get_x (v) < 0)
+    sign = -1;
+  else
+    sign = 0;
+
+  if (sign != 0)
+    {
+      if (c->xsign != 42)
+        {
+          if (c->xsign != sign)
+            c->dx++;
+
+          if (c->dx > 2)
+            {
+              c->convexity = GSK_CONVEXITY_CONCAVE;
+              return FALSE;
+            }
+        }
+      c->xsign = sign;
+    }
+
+  if (graphene_vec2_get_y (v) > 0)
+    sign = 1;
+  else if (graphene_vec2_get_y (v) < 0)
+    sign = -1;
+  else
+    sign = 0;
+
+  if (sign != 0)
+    {
+      if (c->ysign != 42)
+        {
+          if (c->ysign != sign)
+            c->dy++;
+
+          if (c->dy > 2)
+            {
+              c->convexity = GSK_CONVEXITY_CONCAVE;
+              return FALSE;
+            }
+        }
+      c->ysign = sign;
+    }
+
+  return TRUE;
+}
+
+static void
+gsk_convexity_checker_init (GskConvexityChecker *c)
+{
+  c->first_point = GRAPHENE_POINT_INIT(0,0);
+  c->last_point = GRAPHENE_POINT_INIT(0,0);
+  graphene_vec2_init (&c->first_vec, 0, 0);
+  graphene_vec2_init (&c->last_vec, 0, 0);
+  c->expected_direction = GSK_DIR_CHANGE_INVALID;
+  c->first_direction = GSK_PATH_DIRECTION_UNKNOWN;
+  c->reversals = 0;
+  c->finite = TRUE;
+  c->convexity = GSK_CONVEXITY_UNKNOWN;
+  c->xsign = 42;
+  c->ysign = 42;
+  c->dx = 0;
+  c->dy = 0;
+}
+
+static void
+gsk_convexity_checker_move (GskConvexityChecker    *c,
+                            const graphene_point_t *p)
+{
+  c->first_point = c->last_point = *p;
+  c->expected_direction = GSK_DIR_CHANGE_INVALID;
+  c->convexity = GSK_CONVEXITY_CONVEX;
+}
+
+static gboolean
+gsk_convexity_checker_add_point (GskConvexityChecker    *c,
+                                 const graphene_point_t *p)
+{
+  graphene_vec2_t v;
+
+  if (graphene_point_equal (&c->last_point, p))
+    return TRUE;
+
+  graphene_vec2_init (&v,
+                      p->x - c->last_point.x,
+                      p->y - c->last_point.y);
+
+  if (graphene_point_equal (&c->first_point, &c->last_point) &&
+      c->expected_direction == GSK_DIR_CHANGE_INVALID)
+    {
+      graphene_vec2_init_from_vec2 (&c->last_vec, &v);
+      graphene_vec2_init_from_vec2 (&c->first_vec, &v);
+    }
+  else if (!add_vec (c, &v))
+    {
+      c->convexity = GSK_CONVEXITY_CONCAVE;
+      return FALSE;
+    }
+
+  c->last_point = *p;
+  return TRUE;
+}
+
+static gboolean
+gsk_convexity_checker_close (GskConvexityChecker *c)
+{
+  if (!(gsk_convexity_checker_add_point (c, &c->first_point) &&
+        add_vec (c, &c->first_vec)))
+    {
+      c->convexity = GSK_CONVEXITY_CONCAVE;
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+static gboolean
+convex_cb (GskPathOperation        op,
+           const graphene_point_t *pts,
+           gsize                   n_pts,
+           float                   weight,
+           gpointer                user_data)
+{
+  GskConvexityChecker *c = user_data;
+
+  switch (op)
+    {
+    case GSK_PATH_MOVE:
+      gsk_convexity_checker_move (c, &pts[0]);
+      break;
+    case GSK_PATH_CLOSE:
+      if (!gsk_convexity_checker_close (c))
+        return FALSE;
+      break;
+    case GSK_PATH_LINE:
+      if (!gsk_convexity_checker_add_point (c, &pts[1]))
+        return FALSE;
+      break;
+    case GSK_PATH_CURVE:
+      if (!gsk_convexity_checker_add_point (c, &pts[1]) ||
+          !gsk_convexity_checker_add_point (c, &pts[2]) ||
+          !gsk_convexity_checker_add_point (c, &pts[3]))
+        return FALSE;
+      break;
+    case GSK_PATH_CONIC:
+      if (!gsk_convexity_checker_add_point (c, &pts[1]) ||
+          !gsk_convexity_checker_add_point (c, &pts[3]))
+        return FALSE;
+      break;
+    default:
+      g_assert_not_reached ();
+    }
+
+  return TRUE;
+}
+
+GskConvexity
+gsk_contour_compute_convexity (const GskContour *contour)
+{
+  GskConvexityChecker c;
+
+  gsk_convexity_checker_init (&c);
+  gsk_contour_foreach (contour, 0.001, convex_cb, &c);
+
+  g_assert (c.convexity != GSK_CONVEXITY_UNKNOWN);
+
+  return c.convexity;
+}

gsk/gskconvexityprivate.h

@@ -0,0 +1,14 @@
+#pragma once
+
+#include "gskcontourprivate.h"
+
+typedef enum
+{
+  GSK_CONVEXITY_UNKNOWN,
+  GSK_CONVEXITY_CONVEX,
+  GSK_CONVEXITY_CONCAVE,
+} GskConvexity;
+
+GskConvexity gsk_contour_compute_convexity (const GskContour *contour);
+
+

gsk/gskcurveintersect.c

@@ -0,0 +1,650 @@
+/*
+ * Copyright © 2020 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Matthias Clasen <mclasen@redhat.com>
+ */
+
+#include "config.h"
+
+#include "gskcurveprivate.h"
+
+static inline gboolean
+acceptable (float t)
+{
+  return 0 - FLT_EPSILON <= t && t <= 1 + FLT_EPSILON;
+}
+
+
+static int
+line_intersect (const GskCurve   *curve1,
+                const GskCurve   *curve2,
+                float            *t1,
+                float            *t2,
+                graphene_point_t *p,
+                int               n)
+{
+  const graphene_point_t *pts1 = curve1->line.points;
+  const graphene_point_t *pts2 = curve2->line.points;
+  float a1 = pts1[0].x - pts1[1].x;
+  float b1 = pts1[0].y - pts1[1].y;
+  float a2 = pts2[0].x - pts2[1].x;
+  float b2 = pts2[0].y - pts2[1].y;
+  float det = a1 * b2 - b1 * a2;
+
+  if (fabs(det) > 0.01)
+    {
+      float tt =   ((pts1[0].x - pts2[0].x) * b2 - (pts1[0].y - pts2[0].y) * a2) / det;
+      float ss = - ((pts1[0].y - pts2[0].y) * a1 - (pts1[0].x - pts2[0].x) * b1) / det;
+
+      if (acceptable (tt) && acceptable (ss))
+        {
+          p[0].x = pts1[0].x + tt * (pts1[1].x - pts1[0].x);
+          p[0].y = pts1[0].y + tt * (pts1[1].y - pts1[0].y);
+
+          t1[0] = tt;
+          t2[0] = ss;
+
+          return 1;
+        }
+    }
+  else /* parallel lines */
+    {
+      float r = a1 * (pts1[1].y - pts2[0].y) - (pts1[1].x - pts2[0].x) * b1;
+      float dist = (r * r) / (a1 * a1 + b1 * b1);
+      float t, s, tt, ss;
+
+      if (dist > 0.01)
+        return 0;
+
+      if (pts1[1].x != pts1[0].x)
+        {
+          t = (pts2[0].x - pts1[0].x) / (pts1[1].x - pts1[0].x);
+          s = (pts2[1].x - pts1[0].x) / (pts1[1].x - pts1[0].x);
+        }
+      else
+        {
+          t = (pts2[0].y - pts1[0].y) / (pts1[1].y - pts1[0].y);
+          s = (pts2[1].y - pts1[0].y) / (pts1[1].y - pts1[0].y);
+        }
+
+      if ((t < 0 && s < 0) || (t > 1 && s > 1))
+        return 0;
+
+      if (acceptable (t))
+        {
+          t1[0] = t;
+          t2[0] = 0;
+          p[0] = pts2[0];
+        }
+      else if (t < 0)
+        {
+          if (pts2[1].x != pts2[0].x)
+            tt = (pts1[0].x - pts2[0].x) / (pts2[1].x - pts2[0].x);
+          else
+            tt = (pts1[0].y - pts2[0].y) / (pts2[1].y - pts2[0].y);
+
+          t1[0] = 0;
+          t2[0] = tt;
+          p[0] = pts1[0];
+        }
+      else
+        {
+          if (pts2[1].x != pts2[0].x)
+            tt = (pts1[1].x - pts2[0].x) / (pts2[1].x - pts2[0].x);
+          else
+            tt = (pts1[1].y - pts2[0].y) / (pts2[1].y - pts2[0].y);
+
+          t1[0] = 1;
+          t2[0] = tt;
+          p[0] = pts1[1];
+        }
+
+      if (acceptable (s))
+        {
+          if (t2[0] == 1)
+            return 1;
+
+          t1[1] = s;
+          t2[1] = 1;
+          p[1] = pts2[1];
+        }
+      else if (s < 0)
+        {
+          if (t1[0] == 0)
+            return 1;
+
+          if (pts2[1].x != pts2[0].x)
+            ss = (pts1[0].x - pts2[0].x) / (pts2[1].x - pts2[0].x);
+          else
+            ss = (pts1[0].y - pts2[0].y) / (pts2[1].y - pts2[0].y);
+
+          t1[1] = 0;
+          t2[1] = ss;
+          p[1] = pts1[0];
+        }
+      else
+        {
+          if (t1[0] == 1)
+            return 1;
+
+          if (pts2[1].x != pts2[0].x)
+            ss = (pts1[1].x - pts2[0].x) / (pts2[1].x - pts2[0].x);
+          else
+            ss = (pts1[1].y - pts2[0].y) / (pts2[1].y - pts2[0].y);
+
+          t1[1] = 1;
+          t2[1] = ss;
+          p[1] = pts1[1];
+        }
+
+      return 2;
+    }
+
+  return 0;
+}
+
+static void
+get_tangent (const graphene_point_t *p0,
+             const graphene_point_t *p1,
+             graphene_vec2_t        *t)
+{
+  graphene_vec2_init (t, p1->x - p0->x, p1->y - p0->y);
+  graphene_vec2_normalize (t, t);
+}
+
+static void
+align_points (const graphene_point_t *p,
+              const graphene_point_t *a,
+              const graphene_point_t *b,
+              graphene_point_t       *q,
+              int                     n)
+{
+  graphene_vec2_t n1;
+  float angle;
+  float s, c;
+  float dist;
+
+  get_tangent (a, b, &n1);
+  angle = - atan2 (graphene_vec2_get_y (&n1), graphene_vec2_get_x (&n1));
+  sincosf (angle, &s, &c);
+
+  dist = sqrtf ((a->x - b->x)*(a->x - b->x) + (a->y - b->y)*(a->y - b->y));
+
+  for (int i = 0; i < n; i++)
+    {
+      q[i].x = ((p[i].x - a->x) * c - (p[i].y - a->y) * s) / dist;
+      q[i].y = ((p[i].x - a->x) * s + (p[i].y - a->y) * c) / dist;
+    }
+}
+
+static void
+find_point_on_line (const graphene_point_t *p1,
+                    const graphene_point_t *p2,
+                    const graphene_point_t *q,
+                    float                  *t)
+{
+  if (p2->x != p1->x)
+    *t = (q->x - p1->x) / (p2->x - p1->x);
+  else
+    *t = (q->y - p1->y) / (p2->y - p1->y);
+}
+
+static float
+cuberoot (float v)
+{
+  if (v < 0)
+    return -pow (-v, 1.f / 3);
+  return pow (v, 1.f / 3);
+}
+
+/* Solve P = 0 where P is
+ * P = (1-t)^3*pa + 3*t*(1-t)^2*pb + 3*t^2*(1-t)*pc + t^3*pd
+ */
+static int
+get_cubic_roots (float pa, float pb, float pc, float pd, float roots[3])
+{
+  float a, b, c, d;
+  float q, q2;
+  float p, p3;
+  float discriminant;
+  float u1, v1, sd;
+  int n_roots = 0;
+
+  d = -pa + 3*pb - 3*pc + pd;
+  a = 3*pa - 6*pb + 3*pc;
+  b = -3*pa + 3*pb;
+  c = pa;
+
+  if (fabs (d) < 0.0001)
+    {
+      if (fabs (a) < 0.0001)
+        {
+          if (fabs (b) < 0.0001)
+            return 0;
+
+          if (acceptable (-c / b))
+            {
+              roots[0] = -c / b;
+
+              return 1;
+            }
+
+          return 0;
+        }
+      q = sqrt (b*b - 4*a*c);
+      roots[n_roots] = (-b + q) / (2 * a);
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+
+      roots[n_roots] = (-b - q) / (2 * a);
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+
+      return n_roots;
+    }
+
+  a /= d;
+  b /= d;
+  c /= d;
+
+  p = (3*b - a*a)/3;
+  p3 = p/3;
+  q = (2*a*a*a - 9*a*b + 27*c)/27;
+  q2 = q/2;
+  discriminant = q2*q2 + p3*p3*p3;
+
+  if (discriminant < 0)
+    {
+      float mp3 = -p/3;
+      float mp33 = mp3*mp3*mp3;
+      float r = sqrt (mp33);
+      float t = -q / (2*r);
+      float cosphi = t < -1 ? -1 : (t > 1 ? 1 : t);
+      float phi = acos (cosphi);
+      float crtr = cuberoot (r);
+      float t1 = 2*crtr;
+
+      roots[n_roots] = t1 * cos (phi/3) - a/3;
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+      roots[n_roots] = t1 * cos ((phi + 2*M_PI) / 3) - a/3;
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+      roots[n_roots] = t1 * cos ((phi + 4*M_PI) / 3) - a/3;
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+
+    return n_roots;
+  }
+
+  if (discriminant == 0)
+    {
+      u1 = q2 < 0 ? cuberoot (-q2) : -cuberoot (q2);
+      roots[n_roots] = 2*u1 - a/3;
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+      roots[n_roots] = -u1 - a/3;
+      if (acceptable (roots[n_roots]))
+        n_roots++;
+
+      return n_roots;
+    }
+
+  sd = sqrt (discriminant);
+  u1 = cuberoot (sd - q2);
+  v1 = cuberoot (sd + q2);
+  roots[n_roots] = u1 - v1 - a/3;
+  if (acceptable (roots[n_roots]))
+    n_roots++;
+
+  return n_roots;
+}
+
+static int
+line_curve_intersect (const GskCurve   *curve1,
+                      const GskCurve   *curve2,
+                      float            *t1,
+                      float            *t2,
+                      graphene_point_t *p,
+                      int               n)
+{
+  const graphene_point_t *a = &curve1->line.points[0];
+  const graphene_point_t *b = &curve1->line.points[1];
+  graphene_point_t pts[4];
+  float t[3];
+  int m, i, j;
+
+  /* Rotate things to place curve1 on the x axis,
+   * then solve curve2 for y == 0.
+   */
+  align_points (curve2->curve.points, a, b, pts, 4);
+
+  m = get_cubic_roots (pts[0].y, pts[1].y, pts[2].y, pts[3].y, t);
+
+  j = 0;
+  for (i = 0; i < m; i++)
+    {
+      t2[j] = t[i];
+      gsk_curve_get_point (curve2, t2[j], &p[j]);
+      find_point_on_line (a, b, &p[j], &t1[j]);
+      if (acceptable (t1[j]))
+        j++;
+      if (j == n)
+        break;
+    }
+
+  return j;
+}
+
+static void
+curve_intersect_recurse (const GskCurve   *curve1,
+                         const GskCurve   *curve2,
+                         float             t1l,
+                         float             t1r,
+                         float             t2l,
+                         float             t2r,
+                         float            *t1,
+                         float            *t2,
+                         graphene_point_t *p,
+                         int               n,
+                         int              *pos,
+                         float             tolerance,
+                         int               level)
+{
+  GskCurve p11, p12, p21, p22;
+  GskBoundingBox b1, b2;
+  float d1, d2;
+
+  if (*pos == n)
+    return;
+
+  if (level == 20)
+    return;
+
+  gsk_curve_get_bounds (curve1, &b1);
+  gsk_curve_get_bounds (curve2, &b2);
+
+  if (!gsk_bounding_box_intersection (&b1, &b2, NULL))
+    return;
+
+  gsk_curve_get_tight_bounds (curve1, &b1);
+  gsk_curve_get_tight_bounds (curve2, &b2);
+
+  if (!gsk_bounding_box_intersection (&b1, &b2, NULL))
+    return;
+
+  d1 = (t1r - t1l) / 2;
+  d2 = (t2r - t2l) / 2;
+
+  if (b1.max.x - b1.min.x < tolerance && b1.max.y - b1.min.y < tolerance &&
+      b2.max.x - b2.min.x < tolerance && b2.max.y - b2.min.y < tolerance)
+    {
+      graphene_point_t c;
+      t1[*pos] = t1l + d1;
+      t2[*pos] = t2l + d2;
+      gsk_curve_get_point (curve1, 0.5, &c);
+
+      for (int i = 0; i < *pos; i++)
+        {
+          if (graphene_point_near (&c, &p[i], 0.1))
+            return;
+        }
+
+      p[*pos] = c;
+      (*pos)++;
+
+      return;
+    }
+
+  gsk_curve_split (curve1, 0.5, &p11, &p12);
+  gsk_curve_split (curve2, 0.5, &p21, &p22);
+
+  curve_intersect_recurse (&p11, &p21, t1l,      t1l + d1, t2l,      t2l + d2, t1, t2, p, n, pos, tolerance, level + 1);
+  curve_intersect_recurse (&p11, &p22, t1l,      t1l + d1, t2l + d2, t2r,      t1, t2, p, n, pos, tolerance, level + 1);
+  curve_intersect_recurse (&p12, &p21, t1l + d1, t1r,      t2l,      t2l + d2, t1, t2, p, n, pos, tolerance, level + 1);
+  curve_intersect_recurse (&p12, &p22, t1l + d1, t1r,      t2l + d2, t2r,      t1, t2, p, n, pos, tolerance, level + 1);
+}
+
+static int
+curve_intersect (const GskCurve   *curve1,
+                 const GskCurve   *curve2,
+                 float            *t1,
+                 float            *t2,
+                 graphene_point_t *p,
+                 int               n,
+                 float             tolerance)
+{
+  int pos = 0;
+
+  curve_intersect_recurse (curve1, curve2, 0, 1, 0, 1, t1, t2, p, n, &pos, tolerance, 0);
+
+  return pos;
+}
+
+static void
+get_bounds (const GskCurve  *curve,
+            float            tl,
+            float            tr,
+            GskBoundingBox  *bounds)
+{
+  GskCurve c;
+
+  gsk_curve_segment (curve, tl, tr, &c);
+  gsk_curve_get_tight_bounds (&c, bounds);
+}
+
+static void
+general_intersect_recurse (const GskCurve   *curve1,
+                           const GskCurve   *curve2,
+                           float             t1l,
+                           float             t1r,
+                           float             t2l,
+                           float             t2r,
+                           float            *t1,
+                           float            *t2,
+                           graphene_point_t *p,
+                           int               n,
+                           int              *pos,
+                           float             tolerance,
+                           int               level)
+{
+  GskBoundingBox b1, b2;
+  float d1, d2;
+
+  if (*pos == n)
+    return;
+
+  if (level == 20)
+    return;
+
+  get_bounds (curve1, t1l, t1r, &b1);
+  get_bounds (curve2, t2l, t2r, &b2);
+
+  if (!gsk_bounding_box_intersection (&b1, &b2, NULL))
+    return;
+
+  d1 = (t1r - t1l) / 2;
+  d2 = (t2r - t2l) / 2;
+
+  if (b1.max.x - b1.min.x < tolerance && b1.max.y - b1.min.y < tolerance &&
+      b2.max.x - b2.min.x < tolerance && b2.max.y - b2.min.y < tolerance)
+    {
+      graphene_point_t c;
+      t1[*pos] = t1l + d1;
+      t2[*pos] = t2l + d2;
+      gsk_curve_get_point (curve1, t1[*pos], &c);
+
+      for (int i = 0; i < *pos; i++)
+        {
+          if (graphene_point_near (&c, &p[i], tolerance))
+            return;
+        }
+
+      p[*pos] = c;
+      (*pos)++;
+
+      return;
+    }
+
+  /* Note that in the conic case, we cannot just split the curves and
+   * pass the two halves down, since splitting changes the parametrization,
+   * and we need the t's to be valid parameters wrt to the original curve.
+   *
+   * So, instead, we determine the bounding boxes above by always starting
+   * from the original curve. That is a bit less efficient, but also works
+   * for conics.
+   */
+  general_intersect_recurse (curve1, curve2, t1l,      t1l + d1, t2l,      t2l + d2, t1, t2, p, n, pos, tolerance, level + 1);
+  general_intersect_recurse (curve1, curve2, t1l,      t1l + d1, t2l + d2, t2r,      t1, t2, p, n, pos, tolerance, level + 1);
+  general_intersect_recurse (curve1, curve2, t1l + d1, t1r,      t2l,      t2l + d2, t1, t2, p, n, pos, tolerance, level + 1);
+  general_intersect_recurse (curve1, curve2, t1l + d1, t1r,      t2l + d2, t2r,      t1, t2, p, n, pos, tolerance, level + 1);
+}
+
+static int
+general_intersect (const GskCurve   *curve1,
+                   const GskCurve   *curve2,
+                   float            *t1,
+                   float            *t2,
+                   graphene_point_t *p,
+                   int               n,
+                   float             tolerance)
+{
+  int pos = 0;
+
+  general_intersect_recurse (curve1, curve2, 0, 1, 0, 1, t1, t2, p, n, &pos, tolerance, 0);
+
+  return pos;
+}
+
+static int
+curve_self_intersect (const GskCurve   *curve,
+                      float            *t1,
+                      float            *t2,
+                      graphene_point_t *p,
+                      int               n)
+{
+  float tt[3], ss[3], s;
+  graphene_point_t pp[3];
+  int m;
+  GskCurve cs, ce;
+
+  if (curve->op != GSK_PATH_CURVE)
+    return 0;
+
+  s = 0.5;
+  m = gsk_curve_get_curvature_points (curve, tt);
+  for (int i = 0; i < m; i++)
+    {
+      if (gsk_curve_get_curvature (curve, tt[i], NULL) == 0)
+        {
+          s = tt[i];
+          break;
+        }
+    }
+
+  gsk_curve_split (curve, s, &cs, &ce);
+
+  m = curve_intersect (&cs, &ce, tt, ss, pp, 3, 0.001);
+
+  if (m > 1)
+    {
+      /* One of the (at most 2) intersections we found
+       * must be the common point where we split the curve.
+       * It will have a t value of 1 and an s value of 0.
+       */
+      if (fabs (tt[0] - 1) > 1e-3)
+        {
+          t1[0] = t2[0] = tt[0] * s;
+          p[0] = pp[0];
+        }
+      else if (fabs (tt[1] - 1) > 1e-3)
+        {
+          t1[0] = t2[0] = tt[1] * s;
+          p[0] = pp[1];
+        }
+      if (fabs (ss[0]) > 1e-3)
+        {
+          t1[1] = t2[1] = s + ss[0] * (1 - s);
+          p[1] = pp[0];
+        }
+      else if (fabs (ss[1]) > 1e-3)
+        {
+          t1[1] = t2[1] = s + ss[1] * (1 - s);
+          p[1] = pp[1];
+        }
+
+      return 2;
+    }
+
+  return 0;
+}
+
+static inline gboolean
+curve_equal (const GskCurve *c1,
+             const GskCurve *c2)
+{
+  gsize curve_size[] = {
+    sizeof (GskLineCurve),
+    sizeof (GskLineCurve),
+    sizeof (GskLineCurve),
+    sizeof (GskCurveCurve),
+    sizeof (GskConicCurve)
+  };
+
+  return c1->op == c2->op && memcmp (c1, c2, curve_size[c1->op]) == 0;
+}
+
+/* Place intersections between the curves in p, and their Bezier positions
+ * in t1 and t2, up to n. Return the number of intersections found.
+ *
+ * Note that two cubic Beziers can have up to 9 intersections.
+ */
+int
+gsk_curve_intersect (const GskCurve   *curve1,
+                     const GskCurve   *curve2,
+                     float            *t1,
+                     float            *t2,
+                     graphene_point_t *p,
+                     int               n)
+{
+  GskPathOperation op1 = curve1->op;
+  GskPathOperation op2 = curve2->op;
+
+  if (op1 == GSK_PATH_CLOSE)
+    op1 = GSK_PATH_LINE;
+
+  if (op2 == GSK_PATH_CLOSE)
+    op2 = GSK_PATH_LINE;
+
+  if (curve_equal (curve1, curve2))
+    return curve_self_intersect (curve1, t1, t2, p, n);
+
+  /* We special-case line-line and line-curve intersections,
+   * since we can solve them directly.
+   * Everything else is done via bisection.
+   */
+  if (op1 == GSK_PATH_LINE && op2 == GSK_PATH_LINE)
+    return line_intersect (curve1, curve2, t1, t2, p, n);
+  else if (op1 == GSK_PATH_LINE && op2 == GSK_PATH_CURVE)
+    return line_curve_intersect (curve1, curve2, t1, t2, p, n);
+  else if (op1 == GSK_PATH_CURVE && op2 == GSK_PATH_LINE)
+    return line_curve_intersect (curve2, curve1, t2, t1, p, n);
+  else if (op1 == GSK_PATH_CURVE && op2 == GSK_PATH_CURVE)
+    return curve_intersect (curve1, curve2, t1, t2, p, n, 0.001);
+  else
+    return general_intersect (curve1, curve2, t1, t2, p, n, 0.001);
+
+}

gsk/gskcurveprivate.h

@@ -0,0 +1,164 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_CURVE_PRIVATE_H__
+#define __GSK_CURVE_PRIVATE_H__
+
+#include "gskpathopprivate.h"
+#include "gskboundingboxprivate.h"
+
+G_BEGIN_DECLS
+
+typedef gpointer gskpathop;
+
+typedef union _GskCurve GskCurve;
+
+typedef struct _GskLineCurve GskLineCurve;
+typedef struct _GskCurveCurve GskCurveCurve;
+typedef struct _GskConicCurve GskConicCurve;
+
+struct _GskLineCurve
+{
+  GskPathOperation op;
+
+  gboolean padding;
+
+  graphene_point_t points[2];
+};
+
+struct _GskCurveCurve
+{
+  GskPathOperation op;
+
+  gboolean has_coefficients;
+
+  graphene_point_t points[4];
+
+  graphene_point_t coeffs[4];
+};
+
+struct _GskConicCurve
+{
+  GskPathOperation op;
+
+  gboolean has_coefficients;
+
+  /* points[0], points[1], points[3] are the control points,
+   * points[2].x is the weight
+   */
+  graphene_point_t points[4];
+
+  graphene_point_t num[3];
+  graphene_point_t denom[3];
+};
+
+union _GskCurve
+{
+  GskPathOperation op;
+  GskLineCurve line;
+  GskCurveCurve curve;
+  GskConicCurve conic;
+};
+
+typedef gboolean (* GskCurveAddLineFunc) (const graphene_point_t *from,
+                                          const graphene_point_t *to,
+                                          float                   from_progress,
+                                          float                   to_progress,
+                                          gpointer                user_data);
+
+typedef gboolean (* GskCurveAddCurveFunc) (const graphene_point_t points[4],
+                                           gpointer                user_data);
+
+void                    gsk_curve_init                          (GskCurve               *curve,
+                                                                 gskpathop               op);
+void                    gsk_curve_init_foreach                  (GskCurve               *curve,
+                                                                 GskPathOperation        op,
+                                                                 const graphene_point_t *pts,
+                                                                 gsize                   n_pts,
+                                                                 float                   weight);
+
+void                    gsk_curve_get_point                     (const GskCurve         *curve,
+                                                                 float                   progress,
+                                                                 graphene_point_t       *pos);
+void                    gsk_curve_get_tangent                   (const GskCurve         *curve,
+                                                                 float                   progress,
+                                                                 graphene_vec2_t        *tangent);
+void                    gsk_curve_get_normal                    (const GskCurve         *curve,
+                                                                 float                   progress,
+                                                                 graphene_vec2_t        *normal);
+void                    gsk_curve_split                         (const GskCurve         *curve,
+                                                                 float                   progress,
+                                                                 GskCurve               *start,
+                                                                 GskCurve               *end);
+void                    gsk_curve_segment                       (const GskCurve         *curve,
+                                                                 float                   start,
+                                                                 float                   end,
+                                                                 GskCurve               *segment);
+gboolean                gsk_curve_decompose                     (const GskCurve         *curve,
+                                                                 float                   tolerance,
+                                                                 GskCurveAddLineFunc     add_line_func,
+                                                                 gpointer                user_data);
+gboolean                gsk_curve_decompose_curve               (const GskCurve         *curve,
+                                                                 float                   tolerance,
+                                                                 GskCurveAddCurveFunc    add_curve_func,
+                                                                 gpointer                user_data);
+gskpathop               gsk_curve_pathop                        (const GskCurve         *curve);
+#define gsk_curve_builder_to(curve, builder) gsk_path_builder_pathop_to ((builder), gsk_curve_pathop (curve))
+const graphene_point_t *gsk_curve_get_start_point               (const GskCurve         *curve);
+const graphene_point_t *gsk_curve_get_end_point                 (const GskCurve         *curve);
+void                    gsk_curve_get_start_tangent             (const GskCurve         *curve,
+                                                                 graphene_vec2_t        *tangent);
+void                    gsk_curve_get_end_tangent               (const GskCurve         *curve,
+                                                                 graphene_vec2_t        *tangent);
+void                    gsk_curve_get_bounds                    (const GskCurve         *curve,
+                                                                 GskBoundingBox         *bounds);
+void                    gsk_curve_get_tight_bounds              (const GskCurve         *curve,
+                                                                 GskBoundingBox         *bounds);
+
+int                     gsk_curve_intersect                     (const GskCurve         *curve1,
+                                                                 const GskCurve         *curve2,
+                                                                 float                  *t1,
+                                                                 float                  *t2,
+                                                                 graphene_point_t       *p,
+                                                                 int                     n);
+
+void                    gsk_curve_offset                        (const GskCurve         *curve,
+                                                                 float                   distance,
+                                                                 GskCurve               *offset_curve);
+void                    gsk_curve_reverse                       (const GskCurve         *curve,
+                                                                 GskCurve               *reverse);
+
+float                   gsk_curve_get_curvature                 (const GskCurve         *curve,
+                                                                 float                   t,
+                                                                 graphene_point_t       *center);
+
+void                    gsk_curve_print                         (const GskCurve         *curve);
+
+
+int                     gsk_curve_get_curvature_points          (const GskCurve         *curve,
+                                                                 float                   t[3]);
+
+int                     gsk_curve_get_cusps                     (const GskCurve         *curve,
+                                                                 float                   t[2]);
+
+G_END_DECLS
+
+#endif /* __GSK_CURVE_PRIVATE_H__ */
+

gsk/gskdebug.c

@@ -10,6 +10,7 @@ static const GdkDebugKey gsk_debug_keys[] = {
   { "surface", GSK_DEBUG_SURFACE, "Information about surfaces" },
   { "fallback", GSK_DEBUG_FALLBACK, "Information about fallbacks" },
   { "glyphcache", GSK_DEBUG_GLYPH_CACHE, "Information about glyph caching" },
+  { "paths", GSK_DEBUG_PATHS, "Information about path processing" },
   { "geometry", GSK_DEBUG_GEOMETRY, "Show borders (when using cairo)" },
   { "full-redraw", GSK_DEBUG_FULL_REDRAW, "Force full redraws" },
   { "sync", GSK_DEBUG_SYNC, "Sync after each frame" },

gsk/gskdebugprivate.h

@@ -14,6 +14,7 @@ typedef enum {
   GSK_DEBUG_VULKAN                = 1 <<  5,
   GSK_DEBUG_FALLBACK              = 1 <<  6,
   GSK_DEBUG_GLYPH_CACHE           = 1 <<  7,
+  GSK_DEBUG_PATHS                 = 1 <<  8,
   /* flags below may affect behavior */
   GSK_DEBUG_GEOMETRY              = 1 <<  9,
   GSK_DEBUG_FULL_REDRAW           = 1 << 10,

gsk/gskenums.h

@@ -1,5 +1,5 @@
 /* GSK - The GTK Scene Kit
- * Copyright 2016  Endless 
+ * Copyright 2016  Endless
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -50,7 +50,7 @@
  * @GSK_BLUR_NODE: A node that applies a blur
  * @GSK_DEBUG_NODE: Debug information that does not affect the rendering
  * @GSK_GL_SHADER_NODE: A node that uses OpenGL fragment shaders to render
- 
+
  * The type of a node determines what the node is rendering.
  */
 typedef enum {
@@ -73,6 +73,8 @@ typedef enum {
   GSK_REPEAT_NODE,
   GSK_CLIP_NODE,
   GSK_ROUNDED_CLIP_NODE,
+  GSK_FILL_NODE,
+  GSK_STROKE_NODE,
   GSK_SHADOW_NODE,
   GSK_BLEND_NODE,
   GSK_CROSS_FADE_NODE,
@@ -167,6 +169,107 @@ typedef enum {
   GSK_CORNER_BOTTOM_LEFT
 } GskCorner;
 
+/**
+ * GskFillRule:
+ * @GSK_FILL_RULE_WINDING: If the path crosses the ray from
+ *   left-to-right, counts +1. If the path crosses the ray
+ *   from right to left, counts -1. (Left and right are determined
+ *   from the perspective of looking along the ray from the starting
+ *   point.) If the total count is non-zero, the point will be filled.
+ * @GSK_FILL_RULE_EVEN_ODD: Counts the total number of
+ *   intersections, without regard to the orientation of the contour. If
+ *   the total number of intersections is odd, the point will be
+ *   filled.
+ *
+ * #GskFillRule is used to select how paths are filled, for example in
+ * gsk_fill_node_new(). Whether or not a point is included in the fill is
+ * determined by taking a ray from that point to infinity and looking
+ * at intersections with the path. The ray can be in any direction,
+ * as long as it doesn't pass through the end point of a segment
+ * or have a tricky intersection such as intersecting tangent to the path.
+ * (Note that filling is not actually implemented in this way. This
+ * is just a description of the rule that is applied.)
+ *
+ * New entries may be added in future versions.
+ **/
+typedef enum {
+  GSK_FILL_RULE_WINDING,
+  GSK_FILL_RULE_EVEN_ODD
+} GskFillRule;
+
+/**
+ * GskLineCap:
+ * @GSK_LINE_CAP_BUTT: Start and stop the line exactly at the start
+ *   and end point
+ * @GSK_LINE_CAP_ROUND: Use a round ending, the center of the circle
+ *   is the start or end point.
+ * @GSK_LINE_CAP_SQUARE: use squared ending, the center of the square
+ *   is the start or end point.
+ *
+ * Specifies how to render the start and end points of contours or
+ * dashes when stroking.
+ *
+ * The default line cap style is @GSK_LINE_CAP_BUTT.
+ */
+typedef enum {
+  GSK_LINE_CAP_BUTT,
+  GSK_LINE_CAP_ROUND,
+  GSK_LINE_CAP_SQUARE
+} GskLineCap;
+
+/**
+ * GskLineJoin:
+ * @GSK_LINE_JOIN_MITER: Use a sharp, angled corner
+ * @GSK_LINE_JOIN_MITER_CLIP: Use a sharp, angled corner, at a distance
+ * @GSK_LINE_JOIN_ROUND: Use a round join, the center of the circle is
+ *   the joint point
+ * @GSK_LINE_JOIN_BEVEL: use a cut-off join, the join is cut off at half
+ *   the line width from the joint point
+ * @GSK_LINE_JOIN_ARCS: Use a sharp angled corner made from circles
+ *
+ * Specifies how to render the junction of two lines when stroking.
+ *
+ * See [method@Gsk.Stroke.set_miter_limit] for details on the difference
+ * between @GSK_LINE_JOIN_MITER and @GSK_LINE_JOIN_MITER_CLIP.
+ *
+ * The default line join style is @GSK_LINE_JOIN_MITER.
+ **/
+typedef enum {
+  GSK_LINE_JOIN_MITER,
+  GSK_LINE_JOIN_MITER_CLIP,
+  GSK_LINE_JOIN_ROUND,
+  GSK_LINE_JOIN_BEVEL,
+  GSK_LINE_JOIN_ARCS
+} GskLineJoin;
+
+/**
+ * GskPathOperation:
+ * @GSK_PATH_MOVE: A move-to operation, with 1 point describing the
+ *   target point.
+ * @GSK_PATH_LINE: A line-to operation, with 2 points describing the
+ *   start and end point of a straight line.
+ * @GSK_PATH_CLOSE: A close operation ending the current contour with
+ *   a line back to the starting point. Two points describe the start
+ *   and end of the line.
+ * @GSK_PATH_CURVE: A curve-to operation describing a cubic Bézier curve
+ *   with 4 points describing the start point, the two control points
+ *   and the end point of the curve.
+ * @GSK_PATH_CONIC: A weighted quadratic Bézier curve with 3 points
+ *   describing the start point, control point and end point of the
+ *   curve. A weight for the curve will be passed, too.
+ *
+ * Path operations can be used to approximate a #GskPath.
+ *
+ * More values may be added in the future.
+ **/
+typedef enum {
+  GSK_PATH_MOVE,
+  GSK_PATH_CLOSE,
+  GSK_PATH_LINE,
+  GSK_PATH_CURVE,
+  GSK_PATH_CONIC,
+} GskPathOperation;
+
 /**
  * GskSerializationError:
  * @GSK_SERIALIZATION_UNSUPPORTED_FORMAT: The format can not be identified
@@ -251,5 +354,4 @@ typedef enum
   GSK_GL_UNIFORM_TYPE_VEC4,
 } GskGLUniformType;
 
-
 #endif /* __GSK_TYPES_H__ */

gsk/gskpath.h

@@ -0,0 +1,159 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#ifndef __GSK_PATH_H__
+#define __GSK_PATH_H__
+
+#if !defined (__GSK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gsk/gsk.h> can be included directly."
+#endif
+
+
+#include <gsk/gsktypes.h>
+
+G_BEGIN_DECLS
+
+/**
+ * GskPathForeachFlags:
+ * @GSK_PATH_FOREACH_ALLOW_CURVE: Allow emission of `GSK_PATH_CURVE` operations.
+ * @GSK_PATH_FOREACH_ALLOW_CONIC: Allow emission of `GSK_PATH_CONIC` operations.
+ *
+ * Flags that can be passed to [method@Gsk.Path.foreach] to enable additional
+ * features.
+ *
+ * By default, [method@Gsk.Path.foreach] will only emit a path with all
+ * operations flattened to straight lines to allow for maximum compatibility.
+ * The only operations emitted will be `GSK_PATH_MOVE`, `GSK_PATH_LINE` and
+ * `GSK_PATH_CLOSE`.
+ */
+typedef enum
+{
+  GSK_PATH_FOREACH_ALLOW_CURVE = (1 << 0),
+  GSK_PATH_FOREACH_ALLOW_CONIC = (1 << 1)
+} GskPathForeachFlags;
+
+/**
+ * GskPathForeachFunc:
+ * @op: The operation to perform
+ * @pts: The points of the operation
+ * @n_pts: The number of points
+ * @weight: The weight for conic curves, or unused if not a conic curve.
+ * @user_data: The user data provided with the function
+ *
+ * Prototype of the callback to iterate throught the operations of
+ * a path.
+ *
+ * Returns: %TRUE to continue evaluating the path, %FALSE to
+ *   immediately abort and not call the function again.
+ */
+typedef gboolean (* GskPathForeachFunc) (GskPathOperation        op,
+                                         const graphene_point_t *pts,
+                                         gsize                   n_pts,
+                                         float                   weight,
+                                         gpointer                user_data);
+
+#define GSK_TYPE_PATH (gsk_path_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_path_get_type                       (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_new_from_cairo                 (const cairo_path_t     *path);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_ref                            (GskPath                *self);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_unref                          (GskPath                *self);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_print                          (GskPath                *self,
+                                                                 GString                *string);
+GDK_AVAILABLE_IN_ALL
+char *                  gsk_path_to_string                      (GskPath                *self);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_parse                          (const char             *string);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_to_cairo                       (GskPath                *self,
+                                                                 cairo_t                *cr);
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_is_empty                       (GskPath                *self);
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_get_bounds                     (GskPath                *self,
+                                                                 graphene_rect_t        *bounds);
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_get_stroke_bounds              (GskPath                *path,
+                                                                 const GskStroke        *stroke,
+                                                                 graphene_rect_t        *bounds);
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_is_convex                      (GskPath                *self);
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_foreach                        (GskPath                *self,
+                                                                 GskPathForeachFlags     flags,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_reverse                        (GskPath                *self);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_transform                      (GskPath                *self,
+                                                                 GskTransform           *transform);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_stroke                         (GskPath                *self,
+                                                                 GskStroke              *stroke);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_offset                         (GskPath                *self,
+                                                                 float                   distance,
+                                                                 GskLineJoin             line_join,
+                                                                 float                   miter_limit);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_union                          (GskPath                *first,
+                                                                 GskPath                *second,
+                                                                 GskFillRule             fill_rule);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_intersection                   (GskPath                *first,
+                                                                 GskPath                *second,
+                                                                 GskFillRule             fill_rule);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_difference                     (GskPath                *first,
+                                                                 GskPath                *second,
+                                                                 GskFillRule             fill_rule);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_symmetric_difference           (GskPath                *first,
+                                                                 GskPath                *second,
+                                                                 GskFillRule             fill_rule);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_simplify                       (GskPath                *self,
+                                                                 GskFillRule             fill_rule);
+
+
+G_END_DECLS
+
+#endif /* __GSK_PATH_H__ */

gsk/gskpathbuilder.c

@@ -0,0 +1,917 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gskpathbuilder.h"
+
+#include "gskpathprivate.h"
+
+/**
+ * GskPathBuilder:
+ *
+ * A `GskPathBuilder` is an auxiliary object that is used to
+ * create new `GskPath` objects.
+ *
+ * A path is constructed like this:
+ *
+ * ```
+ * GskPath *
+ * construct_path (void)
+ * {
+ *   GskPathBuilder *builder;
+ *
+ *   builder = gsk_path_builder_new ();
+ *
+ *   // add contours to the path here
+ *
+ *   return gsk_path_builder_free_to_path (builder);
+ * }
+ * ```
+ *
+ * Adding contours to the path can be done in two ways.
+ * The easiest option is to use the `gsk_path_builder_add_*` group
+ * of functions that add predefined contours to the current path,
+ * either common shapes like [method@Gsk.PathBuilder.add_circle]
+ * or by adding from other paths like [method@Gsk.PathBuilder.add_path].
+ *
+ * The other option is to define each line and curve manually with
+ * the `gsk_path_builder_*_to` group of functions. You start with
+ * a call to [method@Gsk.PathBuilder.move_to] to set the starting point
+ * and then use multiple calls to any of the drawing functions to
+ * move the pen along the plane. Once you are done, you can call
+ * [method@Gsk.PathBuilder.close] to close the path by connecting it
+ * back with a line to the starting point.
+ * This is similar for how paths are drawn in Cairo.
+ */
+
+struct _GskPathBuilder
+{
+  int ref_count;
+
+  GSList *contours; /* (reverse) list of already recorded contours */
+
+  GskPathFlags flags; /* flags for the current path */
+  graphene_point_t current_point; /* the point all drawing ops start from */
+  GArray *ops; /* operations for current contour - size == 0 means no current contour */
+  GArray *points; /* points for the operations */
+};
+
+G_DEFINE_BOXED_TYPE (GskPathBuilder,
+                     gsk_path_builder,
+                     gsk_path_builder_ref,
+                     gsk_path_builder_unref)
+
+
+/**
+ * gsk_path_builder_new:
+ *
+ * Create a new `GskPathBuilder` object. The resulting builder
+ * would create an empty `GskPath`. Use addition functions to add
+ * types to it.
+ *
+ * Returns: a new `GskPathBuilder`
+ **/
+GskPathBuilder *
+gsk_path_builder_new (void)
+{
+  GskPathBuilder *builder;
+
+  builder = g_slice_new0 (GskPathBuilder);
+  builder->ref_count = 1;
+
+  builder->ops = g_array_new (FALSE, FALSE, sizeof (gskpathop));
+  builder->points = g_array_new (FALSE, FALSE, sizeof (graphene_point_t));
+
+  /* Be explicit here */
+  builder->current_point = GRAPHENE_POINT_INIT (0, 0);
+
+  return builder;
+}
+
+/**
+ * gsk_path_builder_ref:
+ * @builder: a `GskPathBuilder`
+ *
+ * Acquires a reference on the given @builder.
+ *
+ * This function is intended primarily for bindings. `GskPathBuilder` objects
+ * should not be kept around.
+ *
+ * Returns: (transfer none): the given `GskPathBuilder` with
+ *   its reference count increased
+ */
+GskPathBuilder *
+gsk_path_builder_ref (GskPathBuilder *builder)
+{
+  g_return_val_if_fail (builder != NULL, NULL);
+  g_return_val_if_fail (builder->ref_count > 0, NULL);
+
+  builder->ref_count += 1;
+
+  return builder;
+}
+
+/* We're cheating here. Out pathops are relative to the NULL pointer,
+ * so that we can not care about the points GArray reallocating itself
+ * until we create the contour.
+ * This does however mean that we need to not use gsk_pathop_get_points()
+ * without offsetting the returned pointer.
+ */
+static inline gskpathop
+gsk_pathop_encode_index (GskPathOperation op,
+                         gsize            index)
+{
+  return gsk_pathop_encode (op, ((graphene_point_t *) NULL) + index);
+}
+
+static void
+gsk_path_builder_ensure_current (GskPathBuilder *builder)
+{
+  if (builder->ops->len != 0)
+    return;
+
+  builder->flags = GSK_PATH_FLAT;
+  g_array_append_vals (builder->ops, (gskpathop[1]) { gsk_pathop_encode_index (GSK_PATH_MOVE, 0) }, 1);
+  g_array_append_val (builder->points, builder->current_point);
+}
+
+static void
+gsk_path_builder_append_current (GskPathBuilder         *builder,
+                                 GskPathOperation        op,
+                                 gsize                   n_points,
+                                 const graphene_point_t *points)
+{
+  gsk_path_builder_ensure_current (builder);
+
+  g_array_append_vals (builder->ops, (gskpathop[1]) { gsk_pathop_encode_index (op, builder->points->len - 1) }, 1);
+  g_array_append_vals (builder->points, points, n_points);
+
+  builder->current_point = points[n_points - 1];
+}
+
+static void
+gsk_path_builder_end_current (GskPathBuilder *builder)
+{
+  GskContour *contour;
+
+  if (builder->ops->len == 0)
+   return;
+
+  contour = gsk_standard_contour_new (builder->flags,
+                                      (graphene_point_t *) builder->points->data,
+                                      builder->points->len,
+                                      (gskpathop *) builder->ops->data,
+                                      builder->ops->len,
+                                      (graphene_point_t *) builder->points->data - (graphene_point_t *) NULL);
+
+  g_array_set_size (builder->ops, 0);
+  g_array_set_size (builder->points, 0);
+
+  /* do this at the end to avoid inflooping when add_contour calls back here */
+  gsk_path_builder_add_contour (builder, contour);
+}
+
+static void
+gsk_path_builder_clear (GskPathBuilder *builder)
+{
+  gsk_path_builder_end_current (builder);
+
+  g_slist_free_full (builder->contours, g_free);
+  builder->contours = NULL;
+}
+
+/**
+ * gsk_path_builder_unref:
+ * @builder: a `GskPathBuilder`
+ *
+ * Releases a reference on the given @builder.
+ */
+void
+gsk_path_builder_unref (GskPathBuilder *builder)
+{
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (builder->ref_count > 0);
+
+  builder->ref_count -= 1;
+
+  if (builder->ref_count > 0)
+    return;
+
+  gsk_path_builder_clear (builder);
+  g_array_unref (builder->ops);
+  g_array_unref (builder->points);
+  g_slice_free (GskPathBuilder, builder);
+}
+
+/**
+ * gsk_path_builder_free_to_path: (skip)
+ * @builder: a `GskPathBuilder`
+ *
+ * Creates a new `GskPath` from the current state of the
+ * given @builder, and frees the @builder instance.
+ *
+ * Returns: (transfer full): the newly created `GskPath`
+ *   with all the contours added to @builder
+ */
+GskPath *
+gsk_path_builder_free_to_path (GskPathBuilder *builder)
+{
+  GskPath *res;
+
+  g_return_val_if_fail (builder != NULL, NULL);
+
+  res = gsk_path_builder_to_path (builder);
+
+  gsk_path_builder_unref (builder);
+
+  return res;
+}
+
+/**
+ * gsk_path_builder_to_path:
+ * @builder: a `GskPathBuilder`
+ *
+ * Creates a new `GskPath` from the given @builder.
+ *
+ * The given `GskPathBuilder` is reset once this function returns;
+ * you cannot call this function multiple times on the same @builder instance.
+ *
+ * This function is intended primarily for bindings. C code should use
+ * gsk_path_builder_free_to_path().
+ *
+ * Returns: (transfer full): the newly created `GskPath`
+ *   with all the contours added to @builder
+ */
+GskPath *
+gsk_path_builder_to_path (GskPathBuilder *builder)
+{
+  GskPath *path;
+
+  g_return_val_if_fail (builder != NULL, NULL);
+
+  gsk_path_builder_end_current (builder);
+
+  builder->contours = g_slist_reverse (builder->contours);
+
+  path = gsk_path_new_from_contours (builder->contours);
+
+  gsk_path_builder_clear (builder);
+
+  return path;
+}
+
+void
+gsk_path_builder_add_contour (GskPathBuilder *builder,
+                              GskContour     *contour)
+{
+  gsk_path_builder_end_current (builder);
+
+  builder->contours = g_slist_prepend (builder->contours, contour);
+}
+
+/**
+ * gsk_path_builder_get_current_point:
+ * @builder: a #GskPathBuilder
+ *
+ * Gets the current point. The current point is used for relative
+ * drawing commands and updated after every operation.
+ *
+ * When @builder is created, the default current point is set to (0, 0).
+ *
+ * Returns: (transfer none): The current point
+ **/
+const graphene_point_t *
+gsk_path_builder_get_current_point (GskPathBuilder *builder)
+{
+  g_return_val_if_fail (builder != NULL, NULL);
+
+  return &builder->current_point;
+}
+
+/**
+ * gsk_path_builder_add_path:
+ * @builder: a `GskPathBuilder`
+ * @path: (transfer none): the path to append
+ *
+ * Appends all of @path to @builder.
+ **/
+void
+gsk_path_builder_add_path (GskPathBuilder *builder,
+                           GskPath        *path)
+{
+  gsize i;
+
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (path != NULL);
+
+  for (i = 0; i < gsk_path_get_n_contours (path); i++)
+    {
+      const GskContour *contour = gsk_path_get_contour (path, i);
+
+      gsk_path_builder_add_contour (builder, gsk_contour_dup (contour));
+    }
+}
+
+/**
+ * gsk_path_builder_add_rect:
+ * @builder: A `GskPathBuilder`
+ * @rect: The rectangle to add to @builder
+ *
+ * Adds a path representing the given rectangle.
+ *
+ * If the width or height of the rectangle is negative, the start
+ * point will be on the right or bottom, respectively.
+ *
+ * If the the width or height are 0, the path will be a closed
+ * horizontal or vertical line. If both are 0, it'll be a closed dot.
+ **/
+void
+gsk_path_builder_add_rect (GskPathBuilder        *builder,
+                           const graphene_rect_t *rect)
+{
+  GskContour *contour;
+
+  g_return_if_fail (builder != NULL);
+
+  contour = gsk_rect_contour_new (rect);
+  gsk_path_builder_add_contour (builder, contour);
+
+  gsk_contour_get_start_end (contour, NULL, &builder->current_point);
+}
+
+/**
+ * gsk_path_builder_add_rounded_rect:
+ * @builder: a `GskPathBuilder`
+ * @rect: the rounded rect
+ *
+ * Adds @rect as a new contour to the path built in @builder.
+ **/
+void
+gsk_path_builder_add_rounded_rect (GskPathBuilder       *builder,
+                                   const GskRoundedRect *rect)
+{
+  GskContour *contour;
+
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (rect != NULL);
+
+  contour = gsk_rounded_rect_contour_new (rect);
+  gsk_path_builder_add_contour (builder, contour);
+}
+
+/**
+ * gsk_path_builder_add_circle:
+ * @builder: a `GskPathBuilder`
+ * @center: the center of the circle
+ * @radius: the radius of the circle
+ *
+ * Adds a circle with the @center and @radius.
+ **/
+void
+gsk_path_builder_add_circle (GskPathBuilder         *builder,
+                             const graphene_point_t *center,
+                             float                   radius)
+{
+  GskContour *contour;
+
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (center != NULL);
+  g_return_if_fail (radius > 0);
+
+  contour = gsk_circle_contour_new (center, radius, 0, 360);
+  gsk_path_builder_add_contour (builder, contour);
+}
+
+/**
+ * gsk_path_builder_add_ellipse:
+ * @builder: a `GskPathBuilder`
+ * @center: the center point of the ellipse
+ * @radius: the radius of the ellipse in x/y direction
+ *
+ * Adds an ellipse with the given @center and the @radius in
+ * x/y direction.
+ **/
+void
+gsk_path_builder_add_ellipse (GskPathBuilder         *builder,
+                              const graphene_point_t *center,
+                              const graphene_size_t  *radius)
+{
+  const float weight = sqrt(0.5f);
+  graphene_point_t pts[8];
+
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (center != NULL);
+  g_return_if_fail (radius != NULL);
+
+  pts[0] = GRAPHENE_POINT_INIT (center->x + radius->width / 2,
+                                center->y);
+  pts[1] = GRAPHENE_POINT_INIT (center->x + radius->width / 2,
+                                center->y + radius->height / 2);
+  pts[2] = GRAPHENE_POINT_INIT (center->x,
+                                center->y + radius->height / 2);
+  pts[3] = GRAPHENE_POINT_INIT (center->x - radius->width / 2,
+                                center->y + radius->height / 2);
+  pts[4] = GRAPHENE_POINT_INIT (center->x - radius->width / 2,
+                                center->y);
+  pts[5] = GRAPHENE_POINT_INIT (center->x - radius->width / 2,
+                                center->y - radius->height / 2);
+  pts[6] = GRAPHENE_POINT_INIT (center->x,
+                                center->y - radius->height / 2);
+  pts[7] = GRAPHENE_POINT_INIT (center->x + radius->width / 2,
+                                center->y - radius->height / 2);
+
+  gsk_path_builder_move_to (builder, pts[0].x, pts[0].y);
+  gsk_path_builder_conic_to (builder, pts[1].x, pts[1].y, pts[2].x, pts[2].y, weight);
+  gsk_path_builder_conic_to (builder, pts[3].x, pts[3].y, pts[4].x, pts[4].y, weight);
+  gsk_path_builder_conic_to (builder, pts[5].x, pts[5].y, pts[6].x, pts[6].y, weight);
+  gsk_path_builder_conic_to (builder, pts[7].x, pts[7].y, pts[0].x, pts[0].y, weight);
+  gsk_path_builder_close (builder);
+}
+
+/**
+ * gsk_path_builder_move_to:
+ * @builder: a `GskPathBuilder`
+ * @x: x coordinate
+ * @y: y coordinate
+ *
+ * Starts a new contour by placing the pen at @x, @y.
+ *
+ * If `gsk_path_builder_move_to()` is called twice in succession,
+ * the first call will result in a contour made up of a single point.
+ * The second call will start a new contour.
+ **/
+void
+gsk_path_builder_move_to (GskPathBuilder *builder,
+                          float           x,
+                          float           y)
+{
+  g_return_if_fail (builder != NULL);
+
+  gsk_path_builder_end_current (builder);
+
+  builder->current_point = GRAPHENE_POINT_INIT(x, y);
+
+  gsk_path_builder_ensure_current (builder);
+}
+
+/**
+ * gsk_path_builder_rel_move_to:
+ * @builder: a `GskPathBuilder`
+ * @x: x offset
+ * @y: y offset
+ *
+ * Starts a new contour by placing the pen at @x, @y relative to the current
+ * point.
+ *
+ * This is the relative version of [method@Gsk.PathBuilder.move_to].
+ **/
+void
+gsk_path_builder_rel_move_to (GskPathBuilder *builder,
+                              float           x,
+                              float           y)
+{
+  g_return_if_fail (builder != NULL);
+
+  gsk_path_builder_move_to (builder,
+                            builder->current_point.x + x,
+                            builder->current_point.y + y);
+}
+
+/**
+ * gsk_path_builder_line_to:
+ * @builder: a `GskPathBuilder`
+ * @x: x coordinate
+ * @y: y coordinate
+ *
+ * Draws a line from the current point to @x, @y and makes it the new current
+ * point.
+ **/
+void
+gsk_path_builder_line_to (GskPathBuilder *builder,
+                          float           x,
+                          float           y)
+{
+  g_return_if_fail (builder != NULL);
+
+  /* skip the line if it goes to the same point */
+  if (graphene_point_equal (&builder->current_point,
+                            &GRAPHENE_POINT_INIT (x, y)))
+    return;
+
+  gsk_path_builder_append_current (builder,
+                                   GSK_PATH_LINE,
+                                   1, (graphene_point_t[1]) {
+                                     GRAPHENE_POINT_INIT (x, y)
+                                   });
+}
+
+/**
+ * gsk_path_builder_rel_line_to:
+ * @builder: a `GskPathBuilder`
+ * @x: x offset
+ * @y: y offset
+ *
+ * Draws a line from the current point to a point offset to it by @x, @y
+ * and makes it the new current point.
+ *
+ * This is the relative version of [method@Gsk.PathBuilder.line_to].
+ **/
+void
+gsk_path_builder_rel_line_to (GskPathBuilder *builder,
+                              float           x,
+                              float           y)
+{
+  g_return_if_fail (builder != NULL);
+
+  gsk_path_builder_line_to (builder,
+                            builder->current_point.x + x,
+                            builder->current_point.y + y);
+}
+
+/**
+ * gsk_path_builder_curve_to:
+ * @builder: a `GskPathBuilder`
+ * @x1: x coordinate of first control point
+ * @y1: y coordinate of first control point
+ * @x2: x coordinate of second control point
+ * @y2: y coordinate of second control point
+ * @x3: x coordinate of the end of the curve
+ * @y3: y coordinate of the end of the curve
+ *
+ * Adds a [cubic Bézier curve](https://en.wikipedia.org/wiki/B%C3%A9zier_curve)
+ * from the current point to @x3, @y3 with @x1, @y1 and @x2, @y2 as the control
+ * points.
+ *
+ * After this, @x3, @y3 will be the new current point.
+ **/
+void
+gsk_path_builder_curve_to (GskPathBuilder *builder,
+                           float           x1,
+                           float           y1,
+                           float           x2,
+                           float           y2,
+                           float           x3,
+                           float           y3)
+{
+  g_return_if_fail (builder != NULL);
+
+  builder->flags &= ~GSK_PATH_FLAT;
+  gsk_path_builder_append_current (builder,
+                                   GSK_PATH_CURVE,
+                                   3, (graphene_point_t[3]) {
+                                     GRAPHENE_POINT_INIT (x1, y1),
+                                     GRAPHENE_POINT_INIT (x2, y2),
+                                     GRAPHENE_POINT_INIT (x3, y3)
+                                   });
+}
+
+/**
+ * gsk_path_builder_rel_curve_to:
+ * @builder: a `GskPathBuilder`
+ * @x1: x offset of first control point
+ * @y1: y offset of first control point
+ * @x2: x offset of second control point
+ * @y2: y offset of second control point
+ * @x3: x offset of the end of the curve
+ * @y3: y offset of the end of the curve
+ *
+ * Adds a [cubic Bézier curve](https://en.wikipedia.org/wiki/B%C3%A9zier_curve)
+ * from the current point to @x3, @y3 with @x1, @y1 and @x2, @y2 as the control
+ * points. All coordinates are given relative to the current point.
+ *
+ * This is the relative version of [method@Gsk.PathBuilder.curve_to].
+ **/
+void
+gsk_path_builder_rel_curve_to (GskPathBuilder *builder,
+                               float           x1,
+                               float           y1,
+                               float           x2,
+                               float           y2,
+                               float           x3,
+                               float           y3)
+{
+  g_return_if_fail (builder != NULL);
+
+  gsk_path_builder_curve_to (builder,
+                             builder->current_point.x + x1,
+                             builder->current_point.y + y1,
+                             builder->current_point.x + x2,
+                             builder->current_point.y + y2,
+                             builder->current_point.x + x3,
+                             builder->current_point.y + y3);
+}
+
+/**
+ * gsk_path_builder_conic_to:
+ * @builder: a `GskPathBuilder`
+ * @x1: x coordinate of control point
+ * @y1: y coordinate of control point
+ * @x2: x coordinate of the end of the curve
+ * @y2: y coordinate of the end of the curve
+ * @weight: weight of the curve
+ *
+ * Adds a [conic curve](https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline)
+ * from the current point to @x2, @y2 with the given
+ * @weight and @x1, @y1 as the single control point.
+ *
+ * Conic curves can be used to draw ellipses and circles.
+ *
+ * After this, @x2, @y2 will be the new current point.
+ **/
+void
+gsk_path_builder_conic_to (GskPathBuilder *builder,
+                           float           x1,
+                           float           y1,
+                           float           x2,
+                           float           y2,
+                           float           weight)
+{
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (weight >= 0);
+
+  builder->flags &= ~GSK_PATH_FLAT;
+  gsk_path_builder_append_current (builder,
+                                   GSK_PATH_CONIC,
+                                   3, (graphene_point_t[3]) {
+                                     GRAPHENE_POINT_INIT (x1, y1),
+                                     GRAPHENE_POINT_INIT (weight, 0),
+                                     GRAPHENE_POINT_INIT (x2, y2)
+                                   });
+}
+
+/**
+ * gsk_path_builder_rel_conic_to:
+ * @builder: a `GskPathBuilder`
+ * @x1: x offset of control point
+ * @y1: y offset of control point
+ * @x2: x offset of the end of the curve
+ * @y2: y offset of the end of the curve
+ * @weight: weight of the curve
+ *
+ * Adds a [conic curve](https://en.wikipedia.org/wiki/Non-uniform_rational_B-spline)
+ * from the current point to @x2, @y2 with the given
+ * @weight and @x1, @y1 as the single control point.
+ *
+ * This is the relative version of [method@Gsk.PathBuilder.conic_to].
+ **/
+void
+gsk_path_builder_rel_conic_to (GskPathBuilder *builder,
+                               float           x1,
+                               float           y1,
+                               float           x2,
+                               float           y2,
+                               float           weight)
+{
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (weight >= 0);
+
+  gsk_path_builder_conic_to (builder,
+                             builder->current_point.x + x1,
+                             builder->current_point.y + y1,
+                             builder->current_point.x + x2,
+                             builder->current_point.y + y2,
+                             weight);
+}
+
+/**
+ * gsk_path_builder_close:
+ * @builder: a `GskPathBuilder`
+ *
+ * Ends the current contour with a line back to the start point.
+ *
+ * Note that this is different from calling [method@Gsk.PathBuilder.line_to]
+ * with the start point in that the contour will be closed. A closed
+ * contour behaves different from an open one when stroking its start
+ * and end point are considered connected, so they will be joined
+ * via the line join, and not ended with line caps.
+ **/
+void
+gsk_path_builder_close (GskPathBuilder *builder)
+{
+  g_return_if_fail (builder != NULL);
+
+  if (builder->ops->len == 0)
+    return;
+
+  builder->flags |= GSK_PATH_CLOSED;
+  gsk_path_builder_append_current (builder,
+                                   GSK_PATH_CLOSE,
+                                   1, (graphene_point_t[1]) {
+                                     g_array_index (builder->points, graphene_point_t, 0)
+                                   });
+
+  gsk_path_builder_end_current (builder);
+}
+
+
+static void
+arc_segment (GskPathBuilder *builder,
+             double          cx,
+             double          cy,
+             double          rx,
+             double          ry,
+             double          sin_phi,
+             double          cos_phi,
+             double          sin_th0,
+             double          cos_th0,
+             double          sin_th1,
+             double          cos_th1,
+             double          t)
+{
+  double x1, y1, x2, y2, x3, y3;
+
+  x1 = rx * (cos_th0 - t * sin_th0);
+  y1 = ry * (sin_th0 + t * cos_th0);
+  x3 = rx * cos_th1;
+  y3 = ry * sin_th1;
+  x2 = x3 + rx * (t * sin_th1);
+  y2 = y3 + ry * (-t * cos_th1);
+
+  gsk_path_builder_curve_to (builder,
+                             cx + cos_phi * x1 - sin_phi * y1,
+                             cy + sin_phi * x1 + cos_phi * y1,
+                             cx + cos_phi * x2 - sin_phi * y2,
+                             cy + sin_phi * x2 + cos_phi * y2,
+                             cx + cos_phi * x3 - sin_phi * y3,
+                             cy + sin_phi * x3 + cos_phi * y3);
+}
+
+void
+gsk_path_builder_svg_arc_to (GskPathBuilder *builder,
+                             float           rx,
+                             float           ry,
+                             float           x_axis_rotation,
+                             gboolean        large_arc,
+                             gboolean        positive_sweep,
+                             float           x,
+                             float           y)
+{
+  graphene_point_t *current;
+  double x1, y1, x2, y2;
+  double phi, sin_phi, cos_phi;
+  double mid_x, mid_y;
+  double lambda;
+  double d;
+  double k;
+  double x1_, y1_;
+  double cx_, cy_;
+  double  cx, cy;
+  double ux, uy, u_len;
+  double cos_theta1, theta1;
+  double vx, vy, v_len;
+  double dp_uv;
+  double cos_delta_theta, delta_theta;
+  int i, n_segs;
+  double d_theta, theta;
+  double sin_th0, cos_th0;
+  double sin_th1, cos_th1;
+  double th_half;
+  double t;
+
+  if (builder->points->len > 0)
+    {
+      current = &g_array_index (builder->points, graphene_point_t, builder->points->len - 1);
+      x1 = current->x;
+      y1 = current->y;
+    }
+  else
+    {
+      x1 = 0;
+      y1 = 0;
+    }
+  x2 = x;
+  y2 = y;
+
+  phi = x_axis_rotation * M_PI / 180.0;
+  sincos (phi, &sin_phi, &cos_phi);
+
+  rx = fabs (rx);
+  ry = fabs (ry);
+
+  mid_x = (x1 - x2) / 2;
+  mid_y = (y1 - y2) / 2;
+
+  x1_ = cos_phi * mid_x + sin_phi * mid_y;
+  y1_ = - sin_phi * mid_x + cos_phi * mid_y;
+
+  lambda = (x1_ / rx) * (x1_ / rx) + (y1_ / ry) * (y1_ / ry);
+  if (lambda > 1)
+    {
+      lambda = sqrt (lambda);
+      rx *= lambda;
+      ry *= lambda;
+    }
+
+  d = (rx * y1_) * (rx * y1_) + (ry * x1_) * (ry * x1_);
+  if (d == 0)
+    return;
+
+  k = sqrt (fabs ((rx * ry) * (rx * ry) / d - 1.0));
+  if (positive_sweep == large_arc)
+    k = -k;
+
+  cx_ = k * rx * y1_ / ry;
+  cy_ = -k * ry * x1_ / rx;
+
+  cx = cos_phi * cx_ - sin_phi * cy_ + (x1 + x2) / 2;
+  cy = sin_phi * cx_ + cos_phi * cy_ + (y1 + y2) / 2;
+
+  ux = (x1_ - cx_) / rx;
+  uy = (y1_ - cy_) / ry;
+  u_len = sqrt (ux * ux + uy * uy);
+  if (u_len == 0)
+    return;
+
+  cos_theta1 = CLAMP (ux / u_len, -1, 1);
+  theta1 = acos (cos_theta1);
+  if (uy < 0)
+    theta1 = - theta1;
+
+  vx = (- x1_ - cx_) / rx;
+  vy = (- y1_ - cy_) / ry;
+  v_len = sqrt (vx * vx + vy * vy);
+  if (v_len == 0)
+    return;
+
+  dp_uv = ux * vx + uy * vy;
+  cos_delta_theta = CLAMP (dp_uv / (u_len * v_len), -1, 1);
+  delta_theta = acos (cos_delta_theta);
+  if (ux * vy - uy * vx < 0)
+    delta_theta = - delta_theta;
+  if (positive_sweep && delta_theta < 0)
+    delta_theta += 2 * M_PI;
+  else if (!positive_sweep && delta_theta > 0)
+    delta_theta -= 2 * M_PI;
+
+  n_segs = ceil (fabs (delta_theta / (M_PI_2 + 0.001)));
+  d_theta = delta_theta / n_segs;
+  theta = theta1;
+  sincos (theta1, &sin_th1, &cos_th1);
+
+  th_half = d_theta / 2;
+  t = (8.0 / 3.0) * sin (th_half / 2) * sin (th_half / 2) / sin (th_half);
+
+  for (i = 0; i < n_segs; i++)
+    {
+      theta = theta1;
+      theta1 = theta + d_theta;
+      sin_th0 = sin_th1;
+      cos_th0 = cos_th1;
+      sincos (theta1, &sin_th1, &cos_th1);
+      arc_segment (builder,
+                   cx, cy, rx, ry,
+                   sin_phi, cos_phi,
+                   sin_th0, cos_th0,
+                   sin_th1, cos_th1,
+                   t);
+    }
+}
+
+/**
+ * gsk_path_builder_add_layout:
+ * @builder: a `GskPathBuilder`
+ * @layout: the pango layout to add
+ *
+ * Adds the outlines for the glyphs in @layout to @builder.
+ */
+void
+gsk_path_builder_add_layout (GskPathBuilder *builder,
+                             PangoLayout    *layout)
+{
+  cairo_surface_t *surface;
+  cairo_t *cr;
+  cairo_path_t *cairo_path;
+  GskPath *path;
+
+  surface = cairo_recording_surface_create (CAIRO_CONTENT_COLOR_ALPHA, NULL);
+  cr = cairo_create (surface);
+
+  pango_cairo_layout_path (cr, layout);
+  cairo_path = cairo_copy_path_flat (cr);
+  path = gsk_path_new_from_cairo (cairo_path);
+
+  gsk_path_builder_add_path (builder, path);
+
+  gsk_path_unref (path);
+
+  cairo_path_destroy (cairo_path);
+  cairo_destroy (cr);
+  cairo_surface_destroy (surface);
+}

gsk/gskpathbuilder.h

@@ -0,0 +1,132 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#ifndef __GSK_PATH_BUILDER_H__
+#define __GSK_PATH_BUILDER_H__
+
+#if !defined (__GSK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gsk/gsk.h> can be included directly."
+#endif
+
+
+#include <gsk/gskroundedrect.h>
+#include <gsk/gsktypes.h>
+
+G_BEGIN_DECLS
+
+#define GSK_TYPE_PATH_BUILDER (gsk_path_builder_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_path_builder_get_type               (void) G_GNUC_CONST;
+
+GDK_AVAILABLE_IN_ALL
+GskPathBuilder *        gsk_path_builder_new                    (void);
+GDK_AVAILABLE_IN_ALL
+GskPathBuilder *        gsk_path_builder_ref                    (GskPathBuilder         *builder);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_unref                  (GskPathBuilder         *builder);
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_builder_free_to_path           (GskPathBuilder         *builder) G_GNUC_WARN_UNUSED_RESULT;
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_builder_to_path                (GskPathBuilder         *builder) G_GNUC_WARN_UNUSED_RESULT;
+
+GDK_AVAILABLE_IN_ALL
+const graphene_point_t *gsk_path_builder_get_current_point      (GskPathBuilder         *builder);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_path               (GskPathBuilder         *builder,
+                                                                 GskPath                *path);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_rect               (GskPathBuilder         *builder,
+                                                                 const graphene_rect_t  *rect);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_rounded_rect       (GskPathBuilder         *builder,
+                                                                 const GskRoundedRect   *rect);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_circle             (GskPathBuilder         *builder,
+                                                                 const graphene_point_t *center,
+                                                                 float                   radius);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_ellipse            (GskPathBuilder         *builder,
+                                                                 const graphene_point_t *center,
+                                                                 const graphene_size_t  *radius);
+/* next function implemented in gskpathmeasure.c */
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_segment            (GskPathBuilder         *builder,
+                                                                 GskPathMeasure         *measure,
+                                                                 float                   start,
+                                                                 float                   end);
+
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_move_to                (GskPathBuilder         *builder,
+                                                                 float                   x,
+                                                                 float                   y);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_rel_move_to            (GskPathBuilder         *builder,
+                                                                 float                   x,
+                                                                 float                   y);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_line_to                (GskPathBuilder         *builder,
+                                                                 float                   x,
+                                                                 float                   y);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_rel_line_to            (GskPathBuilder         *builder,
+                                                                 float                   x,
+                                                                 float                   y);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_curve_to               (GskPathBuilder         *builder,
+                                                                 float                   x1,
+                                                                 float                   y1,
+                                                                 float                   x2,
+                                                                 float                   y2,
+                                                                 float                   x3,
+                                                                 float                   y3);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_rel_curve_to           (GskPathBuilder         *builder,
+                                                                 float                   x1,
+                                                                 float                   y1,
+                                                                 float                   x2,
+                                                                 float                   y2,
+                                                                 float                   x3,
+                                                                 float                   y3);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_conic_to               (GskPathBuilder         *builder,
+                                                                 float                   x1,
+                                                                 float                   y1,
+                                                                 float                   x2,
+                                                                 float                   y2,
+                                                                 float                   weight);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_rel_conic_to           (GskPathBuilder         *builder,
+                                                                 float                   x1,
+                                                                 float                   y1,
+                                                                 float                   x2,
+                                                                 float                   y2,
+                                                                 float                   weight);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_close                  (GskPathBuilder         *builder);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_layout             (GskPathBuilder         *builder,
+                                                                 PangoLayout            *layout);
+
+G_END_DECLS
+
+#endif /* __GSK_PATH_BUILDER_H__ */

gsk/gskpathdash.c

@@ -0,0 +1,291 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gskpathdashprivate.h"
+
+#include "gskcontourprivate.h"
+#include "gskcurveprivate.h"
+#include "gskpathprivate.h"
+#include "gskstrokeprivate.h"
+
+typedef struct 
+{
+  float offset;                 /* how much of the current dash we've spent */
+  gsize dash_index;             /* goes from 0 to n_dash * 2, so we don't have to care about on/off
+                                   for uneven dashes */
+  gboolean on;                  /* If we're currently dashing or not */
+  gboolean may_close;           /* TRUE if we haven't turned the dash off in this contour */
+  gboolean needs_move_to;       /* If we have emitted the initial move_to() yet */
+  enum {
+    NORMAL, /* no special behavior required */
+    SKIP,   /* skip the next dash */
+    ONLY,   /* only do the first dash */
+    DONE    /* done with the first dash */
+  } first_dash_behavior;        /* How to handle the first dash in the loop. We loop closed contours
+                                   twice to make sure the first dash and the last dash can get joined */
+
+  GskCurve curve;               /* Curve we are currently processing */
+
+  float collect_start;          /* We're collecting multiple line segments when decomposing. */
+  float collect_length;         /* No need to emit a curve for every line segment when the dash is long enough. */
+
+  /* from the stroke */
+  float *dash;
+  gsize n_dash;
+  float dash_length;
+  float dash_offset;
+
+  float tolerance;
+  GskPathForeachFunc func;
+  gpointer user_data;
+} GskPathDash;
+
+static void
+gsk_path_dash_setup (GskPathDash *self)
+{
+  self->offset = fmodf (self->dash_offset, 2 * self->dash_length);
+
+  self->dash_index = 0;
+  self->on = TRUE;
+  self->may_close = TRUE;
+  while (self->offset > self->dash[self->dash_index % self->n_dash])
+    {
+      self->offset -= self->dash[self->dash_index % self->n_dash];
+      self->dash_index++;
+      self->on = !self->on;
+    }
+  if (self->first_dash_behavior != ONLY)
+    self->needs_move_to = TRUE;
+}
+
+static gboolean
+gsk_path_dash_ensure_move_to (GskPathDash            *self,
+                              const graphene_point_t *pt)
+{
+  if (!self->needs_move_to)
+    return TRUE;
+
+  if (!self->func (GSK_PATH_MOVE, pt, 1, 0, self->user_data))
+    return FALSE;
+
+  self->needs_move_to = FALSE;
+  return TRUE;
+}
+
+static gboolean
+gsk_path_dash_add_line_segment (const graphene_point_t *start,
+                                const graphene_point_t *end,
+                                float                   t_start,
+                                float                   t_end,
+                                gpointer                user_data)
+{
+  GskPathDash *self = user_data;
+  float remaining, length, t_step;
+
+  length = graphene_point_distance (start, end, NULL, NULL);
+  if (self->collect_length)
+    {
+      t_start = self->collect_start;
+      length += self->collect_length;
+      self->collect_length = 0;
+    }
+
+  t_step = t_end - t_start;
+  remaining = length;
+
+  while (remaining)
+    {
+      float piece;
+
+      if (self->offset + remaining <= self->dash[self->dash_index % self->n_dash])
+        {
+          /* try collecting multiple line segments */
+          if (t_end < 1.0)
+            {
+              self->collect_start = t_start + t_step * (length - remaining) / length;
+              self->collect_length = remaining;
+              return TRUE;
+            }
+
+          piece = remaining;
+        }
+      else
+        piece = self->dash[self->dash_index % self->n_dash] - self->offset;
+
+      if (self->on)
+        {
+          if (self->first_dash_behavior != SKIP)
+            {
+              GskCurve segment;
+
+              if (piece)
+                {
+                  gsk_curve_segment (&self->curve,
+                                     t_start + t_step * (length - remaining) / length,
+                                     t_start + t_step * (length - (remaining - piece)) / length,
+                                     &segment);
+                  if (!gsk_path_dash_ensure_move_to (self, gsk_curve_get_start_point (&segment)))
+                    return FALSE;
+
+                  if (!gsk_pathop_foreach (gsk_curve_pathop (&segment), self->func, self->user_data))
+                    return FALSE;
+                }
+              else
+                {
+                  graphene_point_t p;
+
+                  gsk_curve_get_point (&self->curve, t_start + t_step * (length - remaining) / length, &p);
+                  if (!gsk_path_dash_ensure_move_to (self, &p))
+                    return FALSE;
+                }
+            }
+        }
+      else
+        {
+          self->may_close = FALSE;
+          if (self->first_dash_behavior == ONLY)
+            {
+              self->first_dash_behavior = DONE;
+              return FALSE;
+            }
+          self->first_dash_behavior = NORMAL;
+        }
+
+      if (self->offset + remaining <= self->dash[self->dash_index % self->n_dash])
+        {
+          self->offset += remaining;
+          remaining = 0;
+        }
+      else
+        {
+          remaining -= piece;
+          self->offset = 0;
+          self->dash_index++;
+          self->dash_index %= 2 * self->n_dash;
+          self->on = !self->on;
+          self->needs_move_to = TRUE;
+        }
+    }
+
+  return TRUE;
+}
+
+static gboolean
+gsk_path_dash_foreach (GskPathOperation        op,
+                       const graphene_point_t *pts,
+                       gsize                   n_pts,
+                       float                   weight,
+                       gpointer                user_data)
+{
+  GskPathDash *self = user_data;
+
+  switch (op)
+  {
+    case GSK_PATH_MOVE:
+      gsk_path_dash_setup (self);
+      break;
+
+    case GSK_PATH_CLOSE:
+      if (self->may_close)
+        {
+          if (graphene_point_equal (&pts[0], &pts[1]))
+            return self->func (GSK_PATH_CLOSE, pts, 2, 0, self->user_data);
+        }
+      else
+        op = GSK_PATH_LINE;
+      G_GNUC_FALLTHROUGH;
+
+    case GSK_PATH_LINE:
+    case GSK_PATH_CURVE:
+    case GSK_PATH_CONIC:
+      gsk_curve_init_foreach (&self->curve, op, pts, n_pts, weight);
+      if (!gsk_curve_decompose (&self->curve, self->tolerance, gsk_path_dash_add_line_segment, self))
+        return FALSE;
+      break;
+
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+
+  return TRUE;
+}
+
+gboolean
+gsk_contour_dash (const GskContour   *contour,
+                  GskStroke          *stroke,
+                  float               tolerance,
+                  GskPathForeachFunc  func,
+                  gpointer            user_data)
+{
+  GskPathDash self = {
+    .offset = 0,
+    .dash = stroke->dash,
+    .n_dash = stroke->n_dash,
+    .dash_length = stroke->dash_length,
+    .dash_offset = stroke->dash_offset,
+    .tolerance = tolerance,
+    .func = func,
+    .user_data = user_data
+  };
+  gboolean is_closed = gsk_contour_get_flags (contour) & GSK_PATH_CLOSED ? TRUE : FALSE;
+
+  self.first_dash_behavior = is_closed ? SKIP : NORMAL;
+  if (!gsk_contour_foreach (contour, tolerance, gsk_path_dash_foreach, &self))
+    return FALSE;
+
+  if (is_closed)
+    {
+      if (self.first_dash_behavior == NORMAL)
+        self.first_dash_behavior = ONLY;
+      else
+        self.first_dash_behavior = NORMAL;
+      self.needs_move_to = !self.on;
+      if (!gsk_contour_foreach (contour, tolerance, gsk_path_dash_foreach, &self) &&
+          self.first_dash_behavior != DONE)
+        return FALSE;
+    }
+
+  return TRUE;
+}
+
+gboolean
+gsk_path_dash (GskPath            *path,
+               GskStroke          *stroke,
+               float               tolerance,
+               GskPathForeachFunc  func,
+               gpointer            user_data)
+{
+  gsize i;
+
+  /* Dashing disabled, no need to do any work */
+  if (stroke->dash_length <= 0)
+    return gsk_path_foreach (path, -1, func, user_data);
+
+  for (i = 0; i < gsk_path_get_n_contours (path); i++)
+    {
+      if (!gsk_contour_dash (gsk_path_get_contour (path, i), stroke, tolerance, func, user_data))
+        return FALSE;
+    }
+
+  return TRUE;
+}
+

gsk/gskpathdashprivate.h

@@ -0,0 +1,50 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_PATH_DASH_PRIVATE_H__
+#define __GSK_PATH_DASH_PRIVATE_H__
+
+#include <gsk/gskpath.h>
+
+G_BEGIN_DECLS
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_dash                           (GskPath                *path,
+                                                                 GskStroke              *stroke,
+                                                                 float                   tolerance,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+
+#ifdef GTK_COMPILATION
+
+#include "gskcontourprivate.h"
+
+gboolean                gsk_contour_dash                        (const GskContour       *contour,
+                                                                 GskStroke              *stroke,
+                                                                 float                   tolerance,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+
+#endif /* GTK_COMPILATION */
+
+G_END_DECLS
+
+#endif /* __GSK_PATH_DASH_PRIVATE_H__ */
+

gsk/gskpathmeasure.c

@@ -0,0 +1,677 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gskpathmeasure.h"
+#include "gskpathbuilder.h"
+
+#include "gskpathbuilder.h"
+#include "gskpathprivate.h"
+
+/**
+ * GskPathMeasure:
+ *
+ * `GskPathMeasure` is an object that allows measuring operations
+ * on `GskPath` objects, to determine quantities like the arc
+ * length of the path, its curvature, or closest points.
+ *
+ * These operations are useful when implementing animations.
+ */
+
+typedef struct _GskContourMeasure GskContourMeasure;
+
+struct _GskContourMeasure
+{
+  float length;
+  gpointer contour_data;
+};
+
+struct _GskPathMeasure
+{
+  /*< private >*/
+  guint ref_count;
+
+  GskPath *path;
+  float tolerance;
+
+  gsize first;
+  gsize last;
+
+  float length;
+  gsize n_contours;
+  GskContourMeasure measures[];
+};
+
+G_DEFINE_BOXED_TYPE (GskPathMeasure, gsk_path_measure,
+                     gsk_path_measure_ref,
+                     gsk_path_measure_unref)
+
+/**
+ * gsk_path_measure_new:
+ * @path: the path to measure
+ *
+ * Creates a measure object for the given @path with a
+ * default tolerance.
+ *
+ * Returns: a new `GskPathMeasure` representing @path
+ **/
+GskPathMeasure *
+gsk_path_measure_new (GskPath *path)
+{
+  return gsk_path_measure_new_with_tolerance (path, GSK_PATH_TOLERANCE_DEFAULT);
+}
+
+/**
+ * gsk_path_measure_new_with_tolerance:
+ * @path: the path to measure
+ * @tolerance: the tolerance for measuring operations
+ *
+ * Creates a measure object for the given @path and @tolerance.
+ *
+ * Returns: a new `GskPathMeasure` representing @path
+ **/
+GskPathMeasure *
+gsk_path_measure_new_with_tolerance (GskPath *path,
+                                     float    tolerance)
+{
+  GskPathMeasure *self;
+  gsize i, n_contours;
+
+  g_return_val_if_fail (path != NULL, NULL);
+  g_return_val_if_fail (tolerance > 0, NULL);
+
+  n_contours = gsk_path_get_n_contours (path);
+
+  self = g_malloc0 (sizeof (GskPathMeasure) + n_contours * sizeof (GskContourMeasure));
+
+  self->ref_count = 1;
+  self->path = gsk_path_ref (path);
+  self->tolerance = tolerance;
+  self->n_contours = n_contours;
+  self->first = 0;
+  self->last = n_contours;
+
+  for (i = 0; i < n_contours; i++)
+    {
+      self->measures[i].contour_data = gsk_contour_init_measure (gsk_path_get_contour (path, i),
+                                                                 self->tolerance,
+                                                                 &self->measures[i].length);
+      self->length += self->measures[i].length;
+    }
+
+  return self;
+}
+
+/**
+ * gsk_path_measure_ref:
+ * @self: a `GskPathMeasure`
+ *
+ * Increases the reference count of a `GskPathMeasure` by one.
+ *
+ * Returns: the passed in `GskPathMeasure`.
+ **/
+GskPathMeasure *
+gsk_path_measure_ref (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, NULL);
+
+  self->ref_count++;
+
+  return self;
+}
+
+/**
+ * gsk_path_measure_unref:
+ * @self: a `GskPathMeasure`
+ *
+ * Decreases the reference count of a `GskPathMeasure` by one.
+ *
+ * If the resulting reference count is zero, frees the object.
+ **/
+void
+gsk_path_measure_unref (GskPathMeasure *self)
+{
+  gsize i;
+
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (self->ref_count > 0);
+
+  self->ref_count--;
+  if (self->ref_count > 0)
+    return;
+
+  for (i = 0; i < self->n_contours; i++)
+    {
+      gsk_contour_free_measure (gsk_path_get_contour (self->path, i),
+                                self->measures[i].contour_data);
+    }
+
+  gsk_path_unref (self->path);
+  g_free (self);
+}
+
+/**
+ * gsk_path_measure_get_path:
+ * @self: a `GskPathMeasure`
+ *
+ * Returns the path that the measure was created for.
+ *
+ * Returns: (transfer none): the path of @self
+ */
+GskPath *
+gsk_path_measure_get_path (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, NULL);
+
+  return self->path;
+}
+
+/**
+ * gsk_path_measure_get_tolerance:
+ * @self: a `GskPathMeasure`
+ *
+ * Returns the tolerance that the measure was created with.
+ *
+ * Returns: the tolerance of @self
+ */
+float
+gsk_path_measure_get_tolerance (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, 0.f);
+
+  return self->tolerance;
+}
+
+/**
+ * gsk_path_measure_get_n_contours:
+ * @self: a `GskPathMeasure`
+ *
+ * Returns the number of contours in the path being measured.
+ *
+ * The returned value is independent of whether @self if restricted
+ * or not.
+ *
+ * Returns: The number of contours
+ **/
+gsize
+gsk_path_measure_get_n_contours (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, 0);
+
+  return self->n_contours;
+}
+
+/**
+ * gsk_path_measure_restrict_to_contour:
+ * @self: a `GskPathMeasure`
+ * @contour: contour to restrict to or (gsize) -1 for using the
+ *   whole path
+ *
+ * Restricts all functions on the path to just the given @contour.
+ *
+ * If @contour >= gsk_path_measure_get_n_contours() - so in
+ * particular when it is set to -1 - the whole path will be used.
+ **/
+void
+gsk_path_measure_restrict_to_contour (GskPathMeasure *self,
+                                      gsize           contour)
+{
+  if (contour >= self->n_contours)
+    {
+      /* use the whole path */
+      self->first = 0;
+      self->last = self->n_contours;
+    }
+  else
+    {
+      /* use just one contour */
+      self->first = contour;
+      self->last = contour + 1;
+    }
+
+  self->length = 0;
+  for (gsize i = self->first; i < self->last; i++)
+    {
+      self->length += self->measures[i].length;
+    }
+}
+
+/**
+ * gsk_path_measure_get_length:
+ * @self: a `GskPathMeasure`
+ *
+ * Gets the length of the path being measured.
+ *
+ * The length is cached, so this function does not do any work.
+ *
+ * Returns: The length of the path measured by @self
+ **/
+float
+gsk_path_measure_get_length (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, 0);
+
+  return self->length;
+}
+
+/**
+ * gsk_path_measure_is_closed:
+ * @self: a `GskPathMeasure`
+ *
+ * Returns if the path being measured represents a single closed
+ * contour.
+ *
+ * Returns: %TRUE if the current path is closed
+ **/
+gboolean
+gsk_path_measure_is_closed (GskPathMeasure *self)
+{
+  const GskContour *contour;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+
+  /* XXX: is the empty path closed? Currently it's not */
+  if (self->last - self->first != 1)
+    return FALSE;
+
+  contour = gsk_path_get_contour (self->path, self->first);
+  return gsk_contour_get_flags (contour) & GSK_PATH_CLOSED ? TRUE : FALSE;
+}
+
+static float
+gsk_path_measure_clamp_distance (GskPathMeasure *self,
+                                 float           distance)
+{
+  if (isnan (distance))
+    return 0;
+
+  return CLAMP (distance, 0, self->length);
+}
+
+/**
+ * gsk_path_measure_get_point:
+ * @self: a `GskPathMeasure`
+ * @distance: distance into the path
+ * @pos: (optional) (out caller-allocates): The coordinates
+ *   of the position at @distance
+ * @tangent: (optional) (out caller-allocates): The tangent
+ *   to the position at @distance
+ *
+ * Calculates the coordinates and tangent of the point @distance
+ * units into the path. The value will be clamped to the length
+ * of the path.
+ *
+ * If the point is a discontinuous edge in the path, the returned
+ * point and tangent will describe the line starting at that point
+ * going forward.
+ *
+ * If @self describes an empty path, the returned point will be
+ * set to `(0, 0)` and the tangent will be the x axis or `(1, 0)`.
+ **/
+void
+gsk_path_measure_get_point (GskPathMeasure   *self,
+                            float             distance,
+                            graphene_point_t *pos,
+                            graphene_vec2_t  *tangent)
+{
+  gsize i;
+
+  g_return_if_fail (self != NULL);
+
+  if (pos == NULL && tangent == NULL)
+    return;
+
+  distance = gsk_path_measure_clamp_distance (self, distance);
+
+  for (i = self->first; i < self->last; i++)
+    {
+      if (distance < self->measures[i].length)
+        break;
+
+      distance -= self->measures[i].length;
+    }
+
+  /* weird corner cases */
+  if (i == self->last)
+    {
+      /* the empty path goes here */
+      if (self->first == self->last)
+        {
+          if (pos)
+            graphene_point_init (pos, 0.f, 0.f);
+          if (tangent)
+            graphene_vec2_init (tangent, 1.f, 0.f);
+          return;
+        }
+      /* rounding errors can make this happen */
+      i = self->last - 1;
+      distance = self->measures[i].length;
+    }
+
+  gsk_contour_get_point (gsk_path_get_contour (self->path, i),
+                         self->measures[i].contour_data,
+                         distance,
+                         pos,
+                         tangent);
+}
+
+/**
+ * gsk_path_measure_get_curvature:
+ * @self: a `GskPathMeasure`
+ * @distance: distance into the path
+ * @center: (optional) (out caller-allocates): The center
+ *   of the osculating circle at the point
+ *
+ * Calculates the curvature at the point @distance units into
+ * the path.
+ *
+ * Optionally, returns the center of the osculating circle as well.
+ *
+ * If the curvature is infinite (at line segments), or does
+ * not exist (at sharp turns), zero is returned, and @center
+ * is not modified.
+ *
+ * Returns: The curvature of the path at the given point
+ */
+float
+gsk_path_measure_get_curvature (GskPathMeasure   *self,
+                                float             distance,
+                                graphene_point_t *center)
+{
+  gsize i;
+
+  g_return_val_if_fail (self != NULL, 0);
+
+  distance = gsk_path_measure_clamp_distance (self, distance);
+
+  for (i = self->first; i < self->last; i++)
+    {
+      if (distance < self->measures[i].length)
+        break;
+
+      distance -= self->measures[i].length;
+    }
+
+  /* weird corner cases */
+  if (i == self->last)
+    {
+      /* the empty path goes here */
+      if (self->first == self->last)
+        return 0;
+
+      /* rounding errors can make this happen */
+      i = self->last - 1;
+      distance = self->measures[i].length;
+    }
+
+  return gsk_contour_get_curvature (gsk_path_get_contour (self->path, i),
+                                    self->measures[i].contour_data,
+                                    distance,
+                                    center);
+}
+
+/**
+ * gsk_path_measure_get_closest_point:
+ * @self: a `GskPathMeasure`
+ * @point: the point to find the closest point to
+ * @out_pos: (optional) (out caller-allocates): return location
+ *   for the closest point
+ *
+ * Gets the point on the path that is closest to @point.
+ *
+ * If the path being measured is empty, return 0 and set
+ * @out_pos to (0, 0).
+ *
+ * This is a simpler and slower version of
+ * [method@Gsk.PathMeasure.get_closest_point_full].
+ * Use that one if you need more control.
+ *
+ * Returns: The offset into the path of the closest point
+ **/
+float
+gsk_path_measure_get_closest_point (GskPathMeasure         *self,
+                                    const graphene_point_t *point,
+                                    graphene_point_t       *out_pos)
+{
+  float result;
+
+  g_return_val_if_fail (self != NULL, 0.0f);
+
+  if (gsk_path_measure_get_closest_point_full (self,
+                                               point,
+                                               INFINITY,
+                                               NULL,
+                                               out_pos,
+                                               &result,
+                                               NULL))
+    return result;
+
+  if (out_pos)
+    *out_pos = GRAPHENE_POINT_INIT (0, 0);
+
+  return 0;
+
+}
+
+/**
+ * gsk_path_measure_get_closest_point_full:
+ * @self: a `GskPathMeasure`
+ * @point: the point to find the closest point to
+ * @threshold: The maximum allowed distance between the path and @point.
+ *   Use INFINITY to look for any point.
+ * @out_distance: (optional) (out caller-allocates): The
+ *   distance between the found closest point on the path and the given
+ *   @point.
+ * @out_pos: (optional) (out caller-allocates): return location
+ *   for the closest point
+ * @out_offset: (optional) (out caller-allocates): The offset into
+ *   the path of the found point
+ * @out_tangent: (optional) (out caller-allocates): return location for
+ *   the tangent at the closest point
+ *
+ * Gets the point on the path that is closest to @point. If no point on
+ * path is closer to @point than @threshold, return %FALSE.
+ *
+ * Returns: %TRUE if a point was found, %FALSE otherwise.
+ **/
+gboolean
+gsk_path_measure_get_closest_point_full (GskPathMeasure         *self,
+                                         const graphene_point_t *point,
+                                         float                   threshold,
+                                         float                  *out_distance,
+                                         graphene_point_t       *out_pos,
+                                         float                  *out_offset,
+                                         graphene_vec2_t        *out_tangent)
+{
+  gboolean result;
+  gsize i;
+  float distance, length;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (point != NULL, FALSE);
+
+  result = FALSE;
+  length = 0;
+
+  for (i = self->first; i < self->last; i++)
+    {
+      if (gsk_contour_get_closest_point (gsk_path_get_contour (self->path, i),
+                                         self->measures[i].contour_data,
+                                         self->tolerance,
+                                         point,
+                                         threshold,
+                                         &distance,
+                                         out_pos,
+                                         out_offset,
+                                         out_tangent))
+        {
+          result = TRUE;
+          if (out_offset)
+            *out_offset += length;
+
+          if (distance < self->tolerance)
+            break;
+          threshold = distance - self->tolerance;
+        }
+
+      length += self->measures[i].length;
+    }
+
+  if (result && out_distance)
+    *out_distance = distance;
+
+  return result;
+}
+
+/**
+ * gsk_path_measure_in_fill:
+ * @self: a #GskPathMeasure
+ * @point: the point to test
+ * @fill_rule: the fill rule to follow
+ *
+ * Returns whether the given point is inside the area that would be
+ * affected if the path of @self was filled according to @fill_rule.
+ *
+ * Returns: %TRUE if @point is inside
+ */
+gboolean
+gsk_path_measure_in_fill (GskPathMeasure   *self,
+                          graphene_point_t *point,
+                          GskFillRule       fill_rule)
+{
+  int winding = 0;
+  gboolean on_edge = FALSE;
+  int i;
+
+  for (i = self->first; i < self->last; i++)
+    {
+      winding += gsk_contour_get_winding (gsk_path_get_contour (self->path, i),
+                                          self->measures[i].contour_data,
+                                          point,
+                                          &on_edge);
+      if (on_edge)
+        return TRUE;
+    }
+
+  switch (fill_rule)
+    {
+    case GSK_FILL_RULE_EVEN_ODD:
+      return winding & 1;
+    case GSK_FILL_RULE_WINDING:
+      return winding != 0;
+    default:
+      g_assert_not_reached ();
+    }
+}
+
+static void
+gsk_path_builder_add_segment_chunk (GskPathBuilder *self,
+                                    GskPathMeasure *measure,
+                                    gboolean        emit_move_to,
+                                    float           start,
+                                    float           end)
+{
+  g_assert (start < end);
+
+  for (gsize i = measure->first; i < measure->last; i++)
+    {
+      if (measure->measures[i].length < start)
+        {
+          start -= measure->measures[i].length;
+          end -= measure->measures[i].length;
+        }
+      else if (start > 0 || end < measure->measures[i].length)
+        {
+          float len = MIN (end, measure->measures[i].length);
+          gsk_contour_add_segment (gsk_path_get_contour (measure->path, i),
+                                   self,
+                                   measure->measures[i].contour_data,
+                                   emit_move_to,
+                                   start,
+                                   len);
+          end -= len;
+          start = 0;
+          if (end <= 0)
+            break;
+        }
+      else
+        {
+          end -= measure->measures[i].length;
+          gsk_path_builder_add_contour (self, gsk_contour_dup (gsk_path_get_contour (measure->path, i)));
+        }
+      emit_move_to = TRUE;
+    }
+}
+
+/**
+ * gsk_path_builder_add_segment:
+ * @builder: a `GskPathBuilder`
+ * @measure: the `GskPathMeasure` to take the segment to
+ * @start: start distance into the path
+ * @end: end distance into the path
+ *
+ * Adds to @builder the segment of @measure from @start to @end.
+ *
+ * The distances are given relative to the length of @measure's path,
+ * from 0 for the beginning of the path to [method@Gsk.PathMeasure.get_length]
+ * for the end of the path. The values will be clamped to that range.
+ *
+ * If @start >= @end after clamping, the path will first add the segment
+ * from @start to the end of the path, and then add the segment from
+ * the beginning to @end. If the path is closed, these segments will
+ * be connected.
+ **/
+void
+gsk_path_builder_add_segment (GskPathBuilder *builder,
+                              GskPathMeasure *measure,
+                              float           start,
+                              float           end)
+{
+  g_return_if_fail (builder != NULL);
+  g_return_if_fail (measure != NULL);
+
+  start = gsk_path_measure_clamp_distance (measure, start);
+  end = gsk_path_measure_clamp_distance (measure, end);
+
+  if (start < end)
+    {
+      gsk_path_builder_add_segment_chunk (builder, measure, TRUE, start, end);
+    }
+  else
+    {
+      /* If the path is closed, we can connect the 2 subpaths. */
+      gboolean closed = gsk_path_measure_is_closed (measure);
+      gboolean need_move_to = !closed;
+
+      if (start < measure->length)
+        gsk_path_builder_add_segment_chunk (builder, measure,
+                                            TRUE,
+                                            start, measure->length);
+      else
+        need_move_to = TRUE;
+
+      if (end > 0)
+        gsk_path_builder_add_segment_chunk (builder, measure,
+                                            need_move_to,
+                                            0, end);
+      if (start == end && closed)
+        gsk_path_builder_close (builder);
+    }
+}

gsk/gskpathmeasure.h

@@ -0,0 +1,92 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#ifndef __GSK_PATH_MEASURE_H__
+#define __GSK_PATH_MEASURE_H__
+
+#if !defined (__GSK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gsk/gsk.h> can be included directly."
+#endif
+
+
+#include <gsk/gskpath.h>
+
+G_BEGIN_DECLS
+
+#define GSK_TYPE_PATH_MEASURE (gsk_path_measure_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_path_measure_get_type               (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GskPathMeasure *        gsk_path_measure_new                    (GskPath                *path);
+GDK_AVAILABLE_IN_ALL
+GskPathMeasure *        gsk_path_measure_new_with_tolerance     (GskPath                *path,
+                                                                 float                   tolerance);
+
+GDK_AVAILABLE_IN_ALL
+GskPathMeasure *        gsk_path_measure_ref                    (GskPathMeasure         *self);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_measure_unref                  (GskPathMeasure         *self);
+
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_path_measure_get_path               (GskPathMeasure         *self) G_GNUC_PURE;
+GDK_AVAILABLE_IN_ALL
+float                   gsk_path_measure_get_tolerance          (GskPathMeasure         *self) G_GNUC_PURE;
+GDK_AVAILABLE_IN_ALL
+gsize                   gsk_path_measure_get_n_contours         (GskPathMeasure         *self) G_GNUC_PURE;
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_measure_restrict_to_contour    (GskPathMeasure         *self,
+                                                                 gsize                   contour);
+
+GDK_AVAILABLE_IN_ALL
+float                   gsk_path_measure_get_length             (GskPathMeasure         *self);
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_measure_is_closed              (GskPathMeasure         *self);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_measure_get_point              (GskPathMeasure         *self,
+                                                                 float                   distance,
+                                                                 graphene_point_t       *pos,
+                                                                 graphene_vec2_t        *tangent);
+GDK_AVAILABLE_IN_ALL
+float                   gsk_path_measure_get_curvature          (GskPathMeasure         *self,
+                                                                 float                   distance,
+                                                                 graphene_point_t       *center);
+
+GDK_AVAILABLE_IN_ALL
+float                   gsk_path_measure_get_closest_point      (GskPathMeasure         *self,
+                                                                 const graphene_point_t *point,
+                                                                 graphene_point_t       *out_pos);
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_measure_get_closest_point_full (GskPathMeasure         *self,
+                                                                 const graphene_point_t *point,
+                                                                 float                   threshold,
+                                                                 float                  *out_distance,
+                                                                 graphene_point_t       *out_pos,
+                                                                 float                  *out_offset,
+                                                                 graphene_vec2_t        *out_tangent);
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_path_measure_in_fill                (GskPathMeasure         *self,
+                                                                 graphene_point_t       *point,
+                                                                 GskFillRule             fill_rule);
+
+G_END_DECLS
+
+#endif /* __GSK_PATH_MEASURE_H__ */

gsk/gskpathopprivate.h

@@ -0,0 +1,179 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_PATHOP_PRIVATE_H__
+#define __GSK_PATHOP_PRIVATE_H__
+
+#include <gsk/gskpath.h>
+#include <gsk/gskpathbuilder.h>
+
+G_BEGIN_DECLS
+
+typedef gpointer gskpathop;
+
+static inline
+gskpathop               gsk_pathop_encode                       (GskPathOperation        op,
+                                                                 const graphene_point_t *pts);
+static inline
+const graphene_point_t *gsk_pathop_points                       (gskpathop               pop);
+static inline
+GskPathOperation        gsk_pathop_op                           (gskpathop               pop);
+
+static inline
+gboolean                gsk_pathop_foreach                      (gskpathop               pop,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+
+/* included inline so tests can use them */
+static inline
+void                    gsk_path_builder_pathop_to              (GskPathBuilder         *builder,
+                                                                 gskpathop               op);
+static inline
+void                    gsk_path_builder_pathop_reverse_to      (GskPathBuilder         *builder,
+                                                                 gskpathop               op);
+
+/* IMPLEMENTATION */
+
+#define GSK_PATHOP_OPERATION_MASK (0x7)
+
+static inline gskpathop
+gsk_pathop_encode (GskPathOperation        op,
+                   const graphene_point_t *pts)
+{
+  /* g_assert (op & GSK_PATHOP_OPERATION_MASK == op); */
+  g_assert ((GPOINTER_TO_SIZE (pts) & GSK_PATHOP_OPERATION_MASK) == 0);
+
+  return GSIZE_TO_POINTER (GPOINTER_TO_SIZE (pts) | op);
+}
+
+static inline const graphene_point_t *
+gsk_pathop_points (gskpathop pop)
+{
+  return GSIZE_TO_POINTER (GPOINTER_TO_SIZE (pop) & ~GSK_PATHOP_OPERATION_MASK);
+}
+
+static inline
+GskPathOperation gsk_pathop_op (gskpathop pop)
+{
+  return GPOINTER_TO_SIZE (pop) & GSK_PATHOP_OPERATION_MASK;
+}
+
+static inline gboolean
+gsk_pathop_foreach (gskpathop          pop,
+                    GskPathForeachFunc func,
+                    gpointer           user_data)
+{
+  switch (gsk_pathop_op (pop))
+  {
+    case GSK_PATH_MOVE:
+      return func (gsk_pathop_op (pop), gsk_pathop_points (pop), 1, 0, user_data);
+
+    case GSK_PATH_CLOSE:
+    case GSK_PATH_LINE:
+      return func (gsk_pathop_op (pop), gsk_pathop_points (pop), 2, 0, user_data);
+
+    case GSK_PATH_CURVE:
+      return func (gsk_pathop_op (pop), gsk_pathop_points (pop), 4, 0, user_data);
+
+    case GSK_PATH_CONIC:
+      {
+        const graphene_point_t *pts = gsk_pathop_points (pop);
+        return func (gsk_pathop_op (pop), (graphene_point_t[3]) { pts[0], pts[1], pts[3] }, 3, pts[2].x, user_data);
+      }
+
+    default:
+      g_assert_not_reached ();
+      return TRUE;
+    }
+}
+
+static inline void
+gsk_path_builder_pathop_to (GskPathBuilder *builder,
+                            gskpathop       op)
+{
+  const graphene_point_t *pts = gsk_pathop_points (op);
+
+  switch (gsk_pathop_op (op))
+  {
+    case GSK_PATH_MOVE:
+      gsk_path_builder_move_to (builder, pts[0].x, pts[0].y);
+      break;
+
+    case GSK_PATH_CLOSE:
+      gsk_path_builder_close (builder);
+      break;
+
+    case GSK_PATH_LINE:
+      gsk_path_builder_line_to (builder, pts[1].x, pts[1].y);
+      break;
+
+    case GSK_PATH_CURVE:
+      gsk_path_builder_curve_to (builder, pts[1].x, pts[1].y, pts[2].x, pts[2].y, pts[3].x, pts[3].y);
+      break;
+
+    case GSK_PATH_CONIC:
+      gsk_path_builder_conic_to (builder, pts[1].x, pts[1].y, pts[3].x, pts[3].y, pts[2].x);
+      break;
+
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+}
+
+static inline void
+gsk_path_builder_pathop_reverse_to (GskPathBuilder *builder,
+                                    gskpathop       op)
+{
+  const graphene_point_t *pts = gsk_pathop_points (op);
+
+  switch (gsk_pathop_op (op))
+  {
+    case GSK_PATH_MOVE:
+      gsk_path_builder_move_to (builder, pts[0].x, pts[0].y);
+      break;
+
+    case GSK_PATH_CLOSE:
+      gsk_path_builder_line_to (builder, pts[0].x, pts[0].y);
+      break;
+
+    case GSK_PATH_LINE:
+      gsk_path_builder_line_to (builder, pts[1].x, pts[1].y);
+      break;
+
+    case GSK_PATH_CURVE:
+      gsk_path_builder_curve_to (builder, pts[2].x, pts[2].y, pts[1].x, pts[1].y, pts[0].x, pts[0].y);
+      break;
+
+    case GSK_PATH_CONIC:
+      gsk_path_builder_conic_to (builder, pts[1].x, pts[1].y, pts[0].x, pts[0].y, pts[2].x);
+      break;
+
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+}
+
+
+G_END_DECLS
+
+#endif /* __GSK_PATHOP_PRIVATE_H__ */
+

gsk/gskpathprivate.h

@@ -0,0 +1,79 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_PATH_PRIVATE_H__
+#define __GSK_PATH_PRIVATE_H__
+
+#include "gskpath.h"
+
+#include "gskcontourprivate.h"
+#include "gskpathopprivate.h"
+
+G_BEGIN_DECLS
+
+/* Same as Skia, so looks like a good value. ¯\_(ツ)_/¯ */
+#define GSK_PATH_TOLERANCE_DEFAULT (0.5)
+
+GskPath *               gsk_path_new_from_contours              (const GSList           *contours);
+
+gsize                   gsk_path_get_n_contours                 (GskPath                *path);
+const GskContour *      gsk_path_get_contour                    (GskPath                *path,
+                                                                 gsize                   i);
+
+GskPathFlags            gsk_path_get_flags                      (GskPath                *self);
+
+gboolean                gsk_path_foreach_with_tolerance         (GskPath                *self,
+                                                                 GskPathForeachFlags     flags,
+                                                                 double                  tolerance,
+                                                                 GskPathForeachFunc      func,
+                                                                 gpointer                user_data);
+
+
+void                    gsk_path_builder_add_contour            (GskPathBuilder         *builder,
+                                                                 GskContour             *contour);
+
+void                    gsk_path_builder_svg_arc_to             (GskPathBuilder         *builder,
+                                                                 float                   rx,
+                                                                 float                   ry,
+                                                                 float                   x_axis_rotation,
+                                                                 gboolean                large_arc,
+                                                                 gboolean                positive_sweep,
+                                                                 float                   x,
+                                                                 float                   y);
+
+typedef enum
+{
+  GSK_PATH_OP_SIMPLIFY,
+  GSK_PATH_OP_UNION,
+  GSK_PATH_OP_INTERSECTION,
+  GSK_PATH_OP_DIFFERENCE,
+  GSK_PATH_OP_XOR
+} GskPathOp;
+
+GskPath *               gsk_path_op                             (GskPathOp               operation,
+                                                                 GskFillRule             fill_rule,
+                                                                 GskPath                *first,
+                                                                 GskPath                *second);
+
+
+G_END_DECLS
+
+#endif /* __GSK_PATH_PRIVATE_H__ */
+

gsk/gskrendernode.c

@@ -58,14 +58,14 @@ value_render_node_init (GValue *value)
 {
   value->data[0].v_pointer = NULL;
 }
- 
+
 static void
 value_render_node_free_value (GValue *value)
 {
   if (value->data[0].v_pointer != NULL)
     gsk_render_node_unref (value->data[0].v_pointer);
 }
- 
+
 static void
 value_render_node_copy_value (const GValue *src,
                               GValue       *dst)
@@ -75,7 +75,7 @@ value_render_node_copy_value (const GValue *src,
   else
     dst->data[0].v_pointer = NULL;
 }
- 
+
 static gpointer
 value_render_node_peek_pointer (const GValue *value)
 {
@@ -738,3 +738,16 @@ gsk_render_node_prefers_high_depth (const GskRenderNode *node)
 {
   return node->prefers_high_depth;
 }
+
+/* Whether we need an offscreen to handle opacity correctly for this node.
+ * We don't if there is only one drawing node inside (could be child
+ * node, or grandchild, or...).
+ *
+ * For containers with multiple children, we can avoid the offscreen if
+ * the children are known not to overlap.
+ */
+gboolean
+gsk_render_node_use_offscreen_for_opacity (const GskRenderNode *node)
+{
+  return node->offscreen_for_opacity;
+}

gsk/gskrendernode.h

@@ -158,6 +158,8 @@ GskRenderNode *         gsk_render_node_deserialize             (GBytes
 #define GSK_TYPE_REPEAT_NODE                    (gsk_repeat_node_get_type())
 #define GSK_TYPE_CLIP_NODE                      (gsk_clip_node_get_type())
 #define GSK_TYPE_ROUNDED_CLIP_NODE              (gsk_rounded_clip_node_get_type())
+#define GSK_TYPE_FILL_NODE                      (gsk_fill_node_get_type())
+#define GSK_TYPE_STROKE_NODE                    (gsk_stroke_node_get_type())
 #define GSK_TYPE_SHADOW_NODE                    (gsk_shadow_node_get_type())
 #define GSK_TYPE_BLEND_NODE                     (gsk_blend_node_get_type())
 #define GSK_TYPE_CROSS_FADE_NODE                (gsk_cross_fade_node_get_type())
@@ -184,6 +186,8 @@ typedef struct _GskColorMatrixNode              GskColorMatrixNode;
 typedef struct _GskRepeatNode                   GskRepeatNode;
 typedef struct _GskClipNode                     GskClipNode;
 typedef struct _GskRoundedClipNode              GskRoundedClipNode;
+typedef struct _GskFillNode                     GskFillNode;
+typedef struct _GskStrokeNode                   GskStrokeNode;
 typedef struct _GskShadowNode                   GskShadowNode;
 typedef struct _GskBlendNode                    GskBlendNode;
 typedef struct _GskCrossFadeNode                GskCrossFadeNode;
@@ -445,6 +449,34 @@ GskRenderNode *         gsk_rounded_clip_node_get_child         (const GskRender
 GDK_AVAILABLE_IN_ALL
 const GskRoundedRect *  gsk_rounded_clip_node_get_clip          (const GskRenderNode      *node) G_GNUC_PURE;
 
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_fill_node_get_type                  (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GskRenderNode *         gsk_fill_node_new                       (GskRenderNode            *child,
+                                                                 GskPath                  *path,
+                                                                 GskFillRule               fill_rule);
+GDK_AVAILABLE_IN_ALL
+GskRenderNode *         gsk_fill_node_get_child                 (const GskRenderNode      *node);
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_fill_node_get_path                  (const GskRenderNode      *node);
+GDK_AVAILABLE_IN_ALL
+GskFillRule             gsk_fill_node_get_fill_rule             (const GskRenderNode      *node);
+
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_stroke_node_get_type                (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GskRenderNode *         gsk_stroke_node_new                     (GskRenderNode            *child,
+                                                                 GskPath                  *path,
+                                                                 const GskStroke          *stroke);
+GDK_AVAILABLE_IN_ALL
+GskRenderNode *         gsk_stroke_node_get_child               (const GskRenderNode      *node);
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_stroke_node_get_path                (const GskRenderNode      *node);
+GDK_AVAILABLE_IN_ALL
+GskPath *               gsk_stroke_node_get_stroke_path         (const GskRenderNode      *node);
+GDK_AVAILABLE_IN_ALL
+const GskStroke *       gsk_stroke_node_get_stroke              (const GskRenderNode      *node);
+
 GDK_AVAILABLE_IN_ALL
 GType                   gsk_shadow_node_get_type                (void) G_GNUC_CONST;
 GDK_AVAILABLE_IN_ALL

gsk/gskrendernodeimpl.c

@@ -23,8 +23,10 @@
 #include "gskcairoblurprivate.h"
 #include "gskdebugprivate.h"
 #include "gskdiffprivate.h"
+#include "gskpath.h"
 #include "gskrendererprivate.h"
 #include "gskroundedrectprivate.h"
+#include "gskstrokeprivate.h"
 #include "gsktransformprivate.h"
 
 #include "gdk/gdktextureprivate.h"
@@ -139,6 +141,7 @@ gsk_color_node_new (const GdkRGBA         *rgba,
 
   self = gsk_render_node_alloc (GSK_COLOR_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   self->color = *rgba;
   graphene_rect_init_from_rect (&node->bounds, bounds);
@@ -284,6 +287,7 @@ gsk_linear_gradient_node_new (const graphene_rect_t  *bounds,
 
   self = gsk_render_node_alloc (GSK_LINEAR_GRADIENT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   graphene_point_init_from_point (&self->start, start);
@@ -336,6 +340,7 @@ gsk_repeating_linear_gradient_node_new (const graphene_rect_t  *bounds,
 
   self = gsk_render_node_alloc (GSK_REPEATING_LINEAR_GRADIENT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   graphene_point_init_from_point (&self->start, start);
@@ -584,6 +589,7 @@ gsk_radial_gradient_node_new (const graphene_rect_t  *bounds,
 
   self = gsk_render_node_alloc (GSK_RADIAL_GRADIENT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   graphene_point_init_from_point (&self->center, center);
@@ -652,6 +658,7 @@ gsk_repeating_radial_gradient_node_new (const graphene_rect_t  *bounds,
 
   self = gsk_render_node_alloc (GSK_REPEATING_RADIAL_GRADIENT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   graphene_point_init_from_point (&self->center, center);
@@ -1030,6 +1037,7 @@ gsk_conic_gradient_node_new (const graphene_rect_t  *bounds,
 
   self = gsk_render_node_alloc (GSK_CONIC_GRADIENT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   graphene_point_init_from_point (&self->center, center);
@@ -1413,6 +1421,7 @@ gsk_border_node_new (const GskRoundedRect *outline,
 
   self = gsk_render_node_alloc (GSK_BORDER_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   gsk_rounded_rect_init_copy (&self->outline, outline);
   memcpy (self->border_width, border_width, sizeof (self->border_width));
@@ -1559,6 +1568,7 @@ gsk_texture_node_new (GdkTexture            *texture,
 
   self = gsk_render_node_alloc (GSK_TEXTURE_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   self->texture = g_object_ref (texture);
   graphene_rect_init_from_rect (&node->bounds, bounds);
@@ -2014,6 +2024,7 @@ gsk_inset_shadow_node_new (const GskRoundedRect *outline,
 
   self = gsk_render_node_alloc (GSK_INSET_SHADOW_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   gsk_rounded_rect_init_copy (&self->outline, outline);
   self->color = *color;
@@ -2313,6 +2324,7 @@ gsk_outset_shadow_node_new (const GskRoundedRect *outline,
 
   self = gsk_render_node_alloc (GSK_OUTSET_SHADOW_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   gsk_rounded_rect_init_copy (&self->outline, outline);
   self->color = *color;
@@ -2506,6 +2518,7 @@ gsk_cairo_node_new (const graphene_rect_t *bounds)
 
   self = gsk_render_node_alloc (GSK_CAIRO_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
 
@@ -2576,6 +2589,7 @@ struct _GskContainerNode
 {
   GskRenderNode render_node;
 
+  gboolean disjoint;
   guint n_children;
   GskRenderNode **children;
 };
@@ -2724,6 +2738,7 @@ gsk_container_node_new (GskRenderNode **children,
   self = gsk_render_node_alloc (GSK_CONTAINER_NODE);
   node = (GskRenderNode *) self;
 
+  self->disjoint = TRUE;
   self->n_children = n_children;
 
   if (n_children == 0)
@@ -2743,11 +2758,14 @@ gsk_container_node_new (GskRenderNode **children,
       for (guint i = 1; i < n_children; i++)
         {
           self->children[i] = gsk_render_node_ref (children[i]);
+          self->disjoint &= !graphene_rect_intersection (&bounds, &(children[i]->bounds), NULL);
           graphene_rect_union (&bounds, &(children[i]->bounds), &bounds);
           node->prefers_high_depth |= gsk_render_node_prefers_high_depth (children[i]);
+          node->offscreen_for_opacity |= children[i]->offscreen_for_opacity;
         }
 
       graphene_rect_init_from_rect (&node->bounds, &bounds);
+      node->offscreen_for_opacity |= !self->disjoint;
     }
 
   return node;
@@ -2801,6 +2819,24 @@ gsk_container_node_get_children (const GskRenderNode *node,
   return self->children;
 }
 
+/*< private>
+ * gsk_container_node_is_disjoint:
+ * @node: a container `GskRenderNode`
+ *
+ * Returns `TRUE` if it is known that the child nodes are not
+ * overlapping. There is no guarantee that they do overlap
+ * if this function return FALSE.
+ *
+ * Returns: `TRUE` if children don't overlap
+ */
+gboolean
+gsk_container_node_is_disjoint (const GskRenderNode *node)
+{
+  const GskContainerNode *self = (const GskContainerNode *) node;
+
+  return self->disjoint;
+}
+
 /*** GSK_TRANSFORM_NODE ***/
 
 /**
@@ -2962,6 +2998,7 @@ gsk_transform_node_new (GskRenderNode *child,
 
   self = gsk_render_node_alloc (GSK_TRANSFORM_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   self->transform = gsk_transform_ref (transform);
@@ -3106,6 +3143,7 @@ gsk_opacity_node_new (GskRenderNode *child,
 
   self = gsk_render_node_alloc (GSK_OPACITY_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   self->opacity = CLAMP (opacity, 0.0, 1.0);
@@ -3309,6 +3347,7 @@ gsk_color_matrix_node_new (GskRenderNode           *child,
 
   self = gsk_render_node_alloc (GSK_COLOR_MATRIX_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   graphene_matrix_init_from_matrix (&self->color_matrix, color_matrix);
@@ -3457,6 +3496,7 @@ gsk_repeat_node_new (const graphene_rect_t *bounds,
 
   self = gsk_render_node_alloc (GSK_REPEAT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = TRUE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
 
@@ -3594,6 +3634,7 @@ gsk_clip_node_new (GskRenderNode         *child,
 
   self = gsk_render_node_alloc (GSK_CLIP_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   graphene_rect_normalize_r (clip, &self->clip);
@@ -3727,6 +3768,7 @@ gsk_rounded_clip_node_new (GskRenderNode         *child,
 
   self = gsk_render_node_alloc (GSK_ROUNDED_CLIP_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   gsk_rounded_rect_init_copy (&self->clip, clip);
@@ -3770,6 +3812,364 @@ gsk_rounded_clip_node_get_clip (const GskRenderNode *node)
   return &self->clip;
 }
 
+/*** GSK_FILL_NODE ***/
+
+struct _GskFillNode
+{
+  GskRenderNode render_node;
+
+  GskRenderNode *child;
+  GskPath *path;
+  GskFillRule fill_rule;
+};
+
+static void
+gsk_fill_node_finalize (GskRenderNode *node)
+{
+  GskFillNode *self = (GskFillNode *) node;
+  GskRenderNodeClass *parent_class = g_type_class_peek (g_type_parent (GSK_TYPE_FILL_NODE));
+
+  gsk_render_node_unref (self->child);
+  gsk_path_unref (self->path);
+
+  parent_class->finalize (node);
+}
+
+static void
+gsk_fill_node_draw (GskRenderNode *node,
+                    cairo_t       *cr)
+{
+  GskFillNode *self = (GskFillNode *) node;
+
+  cairo_save (cr);
+
+  switch (self->fill_rule)
+  {
+    case GSK_FILL_RULE_WINDING:
+      cairo_set_fill_rule (cr, CAIRO_FILL_RULE_WINDING);
+      break;
+    case GSK_FILL_RULE_EVEN_ODD:
+      cairo_set_fill_rule (cr, CAIRO_FILL_RULE_EVEN_ODD);
+      break;
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+  gsk_path_to_cairo (self->path, cr);
+  cairo_clip (cr);
+
+  gsk_render_node_draw (self->child, cr);
+
+  cairo_restore (cr);
+}
+
+static void
+gsk_fill_node_diff (GskRenderNode  *node1,
+                    GskRenderNode  *node2,
+                    cairo_region_t *region)
+{
+  GskFillNode *self1 = (GskFillNode *) node1;
+  GskFillNode *self2 = (GskFillNode *) node2;
+
+  if (self1->path == self2->path)
+    {
+      cairo_region_t *sub;
+      cairo_rectangle_int_t clip_rect;
+      graphene_rect_t rect;
+
+      sub = cairo_region_create();
+      gsk_render_node_diff (self1->child, self2->child, sub);
+      graphene_rect_union (&node1->bounds, &node2->bounds, &rect);
+      rectangle_init_from_graphene (&clip_rect, &rect);
+      cairo_region_intersect_rectangle (sub, &clip_rect);
+      cairo_region_union (region, sub);
+      cairo_region_destroy (sub);
+    }
+  else
+    {
+      gsk_render_node_diff_impossible (node1, node2, region);
+    }
+}
+
+/**
+ * gsk_fill_node_new:
+ * @child: The node to fill the area with
+ * @path: The path describing the area to fill
+ * @fill_rule: The fill rule to use
+ *
+ * Creates a `GskRenderNode` that will fill the @child in the area
+ * given by @path and @fill_rule.
+ *
+ * Returns: (transfer none) (type GskFillNode): A new `GskRenderNode`
+ */
+GskRenderNode *
+gsk_fill_node_new (GskRenderNode *child,
+                   GskPath       *path,
+                   GskFillRule    fill_rule)
+{
+  GskFillNode *self;
+  GskRenderNode *node;
+  graphene_rect_t path_bounds;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE (child), NULL);
+  g_return_val_if_fail (path != NULL, NULL);
+
+  self = gsk_render_node_alloc (GSK_FILL_NODE);
+  node = (GskRenderNode *) self;
+
+  self->child = gsk_render_node_ref (child);
+  self->path = gsk_path_ref (path);
+  self->fill_rule = fill_rule;
+
+  if (gsk_path_get_bounds (path, &path_bounds))
+    graphene_rect_intersection (&path_bounds, &child->bounds, &node->bounds);
+  else
+    graphene_rect_init_from_rect (&node->bounds, graphene_rect_zero ());
+
+  return node;
+}
+
+/**
+ * gsk_fill_node_get_child:
+ * @node: (type GskFillNode): a fill `GskRenderNode`
+ *
+ * Gets the child node that is getting drawn by the given @node.
+ *
+ * Returns: (transfer none): The child that is getting drawn
+ **/
+GskRenderNode *
+gsk_fill_node_get_child (const GskRenderNode *node)
+{
+  const GskFillNode *self = (const GskFillNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_FILL_NODE), NULL);
+
+  return self->child;
+}
+
+/**
+ * gsk_fill_node_get_path:
+ * @node: (type GskFillNode): a fill `GskRenderNode`
+ *
+ * Retrievs the path used to describe the area filled with the contents of
+ * the @node.
+ *
+ * Returns: (transfer none): a `GskPath`
+ */
+GskPath *
+gsk_fill_node_get_path (const GskRenderNode *node)
+{
+  const GskFillNode *self = (const GskFillNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_FILL_NODE), NULL);
+
+  return self->path;
+}
+
+/**
+ * gsk_fill_node_get_fill_rule:
+ * @node: (type GskFillNode): a fill `GskRenderNode`
+ *
+ * Retrievs the fill rule used to determine how the path is filled.
+ *
+ * Returns: a `GskFillRule`
+ */
+GskFillRule
+gsk_fill_node_get_fill_rule (const GskRenderNode *node)
+{
+  const GskFillNode *self = (const GskFillNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_FILL_NODE), GSK_FILL_RULE_WINDING);
+
+  return self->fill_rule;
+}
+
+/*** GSK_STROKE_NODE ***/
+
+struct _GskStrokeNode
+{
+  GskRenderNode render_node;
+
+  GskRenderNode *child;
+  GskPath *path;
+  GskPath *stroke_path;
+  GskStroke stroke;
+};
+
+static void
+gsk_stroke_node_finalize (GskRenderNode *node)
+{
+  GskStrokeNode *self = (GskStrokeNode *) node;
+  GskRenderNodeClass *parent_class = g_type_class_peek (g_type_parent (GSK_TYPE_STROKE_NODE));
+
+  gsk_render_node_unref (self->child);
+  gsk_path_unref (self->path);
+  gsk_path_unref (self->stroke_path);
+  gsk_stroke_clear (&self->stroke);
+
+  parent_class->finalize (node);
+}
+
+static void
+gsk_stroke_node_draw (GskRenderNode *node,
+                      cairo_t       *cr)
+{
+  GskStrokeNode *self = (GskStrokeNode *) node;
+
+  cairo_save (cr);
+
+  gsk_cairo_rectangle (cr, &self->child->bounds);
+  cairo_clip (cr);
+
+  cairo_push_group (cr);
+  gsk_render_node_draw (self->child, cr);
+  cairo_pop_group_to_source (cr);
+
+  gsk_stroke_to_cairo (&self->stroke, cr);
+
+  gsk_path_to_cairo (self->path, cr);
+  cairo_stroke (cr);
+
+  cairo_restore (cr);
+}
+
+static void
+gsk_stroke_node_diff (GskRenderNode  *node1,
+                      GskRenderNode  *node2,
+                      cairo_region_t *region)
+{
+  GskStrokeNode *self1 = (GskStrokeNode *) node1;
+  GskStrokeNode *self2 = (GskStrokeNode *) node2;
+
+  if (self1->path == self2->path &&
+      gsk_stroke_equal (&self1->stroke, &self2->stroke))
+    {
+      cairo_region_t *sub;
+
+      sub = cairo_region_create();
+      gsk_render_node_diff (self1->child, self2->child, sub);
+      cairo_region_union (region, sub);
+      cairo_region_destroy (sub);
+    }
+  else
+    {
+      gsk_render_node_diff_impossible (node1, node2, region);
+    }
+}
+
+/**
+ * gsk_stroke_node_new:
+ * @child: The node to stroke the area with
+ * @path: (transfer none): The path describing the area to stroke
+ * @stroke: (transfer none): The stroke attributes to use
+ *
+ * Creates a `GskRenderNode` that will stroke the @child along the given
+ * @path using the attributes defined in @stroke.
+ *
+ * Returns: (transfer none) (type GskStrokeNode): A new `GskRenderNode`
+ */
+GskRenderNode *
+gsk_stroke_node_new (GskRenderNode   *child,
+                     GskPath         *path,
+                     const GskStroke *stroke)
+{
+  GskStrokeNode *self;
+  GskRenderNode *node;
+  graphene_rect_t path_bounds;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE (child), NULL);
+  g_return_val_if_fail (path != NULL, NULL);
+  g_return_val_if_fail (stroke != NULL, NULL);
+
+  self = gsk_render_node_alloc (GSK_STROKE_NODE);
+  node = (GskRenderNode *) self;
+
+  self->child = gsk_render_node_ref (child);
+  self->path = gsk_path_ref (path);
+  gsk_stroke_init_copy (&self->stroke, stroke);
+  self->stroke_path = gsk_path_stroke (path, &self->stroke);
+
+  if (gsk_path_get_stroke_bounds (path, stroke, &path_bounds))
+    graphene_rect_intersection (&path_bounds, &child->bounds, &node->bounds);
+  else
+    graphene_rect_init_from_rect (&node->bounds, graphene_rect_zero ());
+
+  return node;
+}
+
+/**
+ * gsk_stroke_node_get_child:
+ * @node: (type GskStrokeNode): a stroke `GskRenderNode`
+ *
+ * Gets the child node that is getting drawn by the given @node.
+ *
+ * Returns: (transfer none): The child that is getting drawn
+ **/
+GskRenderNode *
+gsk_stroke_node_get_child (const GskRenderNode *node)
+{
+  const GskStrokeNode *self = (const GskStrokeNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_STROKE_NODE), NULL);
+
+  return self->child;
+}
+
+/**
+ * gsk_stroke_node_get_path:
+ * @node: (type GskStrokeNode): a stroke `GskRenderNode`
+ *
+ * Retrieves the path that will be stroked with the contents of
+ * the @node.
+ *
+ * Returns: (transfer none): a `GskPath`
+ */
+GskPath *
+gsk_stroke_node_get_path (const GskRenderNode *node)
+{
+  const GskStrokeNode *self = (const GskStrokeNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_STROKE_NODE), NULL);
+
+  return self->path;
+}
+
+/**
+ * gsk_stroke_node_get_stroke_path:
+ * @node: (type GskStrokeNode): a stroke `GskRenderNode`
+ *
+ * Retrieves the stroke path that will be filled.
+ *
+ * Returns: (transfer none): a `GskPath`
+ */
+GskPath *
+gsk_stroke_node_get_stroke_path (const GskRenderNode *node)
+{
+  const GskStrokeNode *self = (const GskStrokeNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_STROKE_NODE), NULL);
+
+  return self->stroke_path;
+}
+
+/**
+ * gsk_stroke_node_get_stroke:
+ * @node: (type GskStrokeNode): a stroke `GskRenderNode`
+ *
+ * Retrievs the stroke attributes used in this @node.
+ *
+ * Returns: a `GskStroke`
+ */
+const GskStroke *
+gsk_stroke_node_get_stroke (const GskRenderNode *node)
+{
+  const GskStrokeNode *self = (const GskStrokeNode *) node;
+
+  g_return_val_if_fail (GSK_IS_RENDER_NODE_TYPE (node, GSK_STROKE_NODE), NULL);
+
+  return &self->stroke;
+}
+
 /*** GSK_SHADOW_NODE ***/
 
 /**
@@ -3946,6 +4346,7 @@ gsk_shadow_node_new (GskRenderNode   *child,
 
   self = gsk_render_node_alloc (GSK_SHADOW_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   self->n_shadows = n_shadows;
@@ -4142,6 +4543,7 @@ gsk_blend_node_new (GskRenderNode *bottom,
 
   self = gsk_render_node_alloc (GSK_BLEND_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = TRUE;
 
   self->bottom = gsk_render_node_ref (bottom);
   self->top = gsk_render_node_ref (top);
@@ -4292,6 +4694,7 @@ gsk_cross_fade_node_new (GskRenderNode *start,
 
   self = gsk_render_node_alloc (GSK_CROSS_FADE_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = TRUE;
 
   self->start = gsk_render_node_ref (start);
   self->end = gsk_render_node_ref (end);
@@ -4478,6 +4881,7 @@ gsk_text_node_new (PangoFont              *font,
 
   self = gsk_render_node_alloc (GSK_TEXT_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = FALSE;
 
   self->font = g_object_ref (font);
   self->color = *color;
@@ -4884,6 +5288,7 @@ gsk_blur_node_new (GskRenderNode *child,
 
   self = gsk_render_node_alloc (GSK_BLUR_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   self->radius = radius;
@@ -5013,6 +5418,7 @@ gsk_debug_node_new (GskRenderNode *child,
 
   self = gsk_render_node_alloc (GSK_DEBUG_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = child->offscreen_for_opacity;
 
   self->child = gsk_render_node_ref (child);
   self->message = message;
@@ -5174,6 +5580,7 @@ gsk_gl_shader_node_new (GskGLShader           *shader,
 
   self = gsk_render_node_alloc (GSK_GL_SHADER_NODE);
   node = (GskRenderNode *) self;
+  node->offscreen_for_opacity = TRUE;
 
   graphene_rect_init_from_rect (&node->bounds, bounds);
   self->shader = g_object_ref (shader);
@@ -5292,6 +5699,8 @@ GSK_DEFINE_RENDER_NODE_TYPE (gsk_color_matrix_node, GSK_COLOR_MATRIX_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_repeat_node, GSK_REPEAT_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_clip_node, GSK_CLIP_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_rounded_clip_node, GSK_ROUNDED_CLIP_NODE)
+GSK_DEFINE_RENDER_NODE_TYPE (gsk_fill_node, GSK_FILL_NODE)
+GSK_DEFINE_RENDER_NODE_TYPE (gsk_stroke_node, GSK_STROKE_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_shadow_node, GSK_SHADOW_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_blend_node, GSK_BLEND_NODE)
 GSK_DEFINE_RENDER_NODE_TYPE (gsk_cross_fade_node, GSK_CROSS_FADE_NODE)
@@ -5591,6 +6000,38 @@ gsk_render_node_init_types_once (void)
     gsk_render_node_types[GSK_ROUNDED_CLIP_NODE] = node_type;
   }
 
+  {
+    const GskRenderNodeTypeInfo node_info =
+    {
+      GSK_FILL_NODE,
+      sizeof (GskFillNode),
+      NULL,
+      gsk_fill_node_finalize,
+      gsk_fill_node_draw,
+      NULL,
+      gsk_fill_node_diff,
+    };
+
+    GType node_type = gsk_render_node_type_register_static (I_("GskFillNode"), &node_info);
+    gsk_render_node_types[GSK_FILL_NODE] = node_type;
+  }
+
+  {
+    const GskRenderNodeTypeInfo node_info =
+    {
+      GSK_STROKE_NODE,
+      sizeof (GskStrokeNode),
+      NULL,
+      gsk_stroke_node_finalize,
+      gsk_stroke_node_draw,
+      NULL,
+      gsk_stroke_node_diff,
+    };
+
+    GType node_type = gsk_render_node_type_register_static (I_("GskStrokeNode"), &node_info);
+    gsk_render_node_types[GSK_STROKE_NODE] = node_type;
+  }
+
   {
     const GskRenderNodeTypeInfo node_info =
     {

gsk/gskrendernodeparser.c

@@ -23,9 +23,13 @@
 
 #include "gskrendernodeparserprivate.h"
 
+#include "gskpath.h"
+#include "gskpathbuilder.h"
 #include "gskroundedrectprivate.h"
 #include "gskrendernodeprivate.h"
+#include "gskstroke.h"
 #include "gsktransformprivate.h"
+#include "gskenumtypes.h"
 
 #include "gdk/gdkrgbaprivate.h"
 #include "gdk/gdktextureprivate.h"
@@ -399,7 +403,10 @@ parse_string (GtkCssParser *parser,
 
   token = gtk_css_parser_get_token (parser);
   if (!gtk_css_token_is (token, GTK_CSS_TOKEN_STRING))
-    return FALSE;
+    {
+      gtk_css_parser_error_syntax (parser, "Expected a string");
+      return FALSE;
+    }
 
   s = g_strdup (token->string.string);
   gtk_css_parser_consume_token (parser);
@@ -955,6 +962,26 @@ create_default_render_node (void)
   return gsk_color_node_new (&GDK_RGBA("FF00CC"), &GRAPHENE_RECT_INIT (0, 0, 50, 50));
 }
 
+static GskPath *
+create_default_path (void)
+{
+  GskPathBuilder *builder;
+  guint i;
+
+  builder = gsk_path_builder_new ();
+
+  gsk_path_builder_move_to (builder, 25, 0);
+  for (i = 1; i < 5; i++)
+    {
+      gsk_path_builder_line_to (builder,
+                                sin (i * G_PI * 0.8) * 25 + 25,
+                                -cos (i * G_PI * 0.8) * 25 + 25);
+    }
+  gsk_path_builder_close (builder);
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
 static GskRenderNode *
 parse_color_node (GtkCssParser *parser)
 {
@@ -1102,7 +1129,7 @@ parse_conic_gradient_node (GtkCssParser *parser)
       g_array_append_val (stops, to);
     }
 
-  result = gsk_conic_gradient_node_new (&bounds, &center, rotation, 
+  result = gsk_conic_gradient_node_new (&bounds, &center, rotation,
                                         (GskColorStop *) stops->data, stops->len);
 
   g_array_free (stops, TRUE);
@@ -1388,7 +1415,7 @@ parse_cairo_node (GtkCssParser *parser)
   parse_declarations (parser, declarations, G_N_ELEMENTS(declarations));
 
   node = gsk_cairo_node_new (&bounds);
-  
+
   if (surface != NULL)
     {
       cairo_t *cr = gsk_cairo_node_get_draw_context (node);
@@ -1765,6 +1792,208 @@ parse_rounded_clip_node (GtkCssParser *parser)
   return result;
 }
 
+static gboolean
+parse_path (GtkCssParser *parser,
+            gpointer      out_path)
+{
+  GskPath *path;
+  char *str = NULL;
+
+  if (!parse_string (parser, &str))
+    return FALSE;
+
+  path = gsk_path_parse (str);
+  g_free (str);
+
+  if (path == NULL)
+    {
+      gtk_css_parser_error_value (parser, "Invalid path");
+      return FALSE;
+    }
+
+  *((GskPath **) out_path) = path;
+
+  return TRUE;
+}
+
+static void
+clear_path (gpointer inout_path)
+{
+  g_clear_pointer ((GskPath **) inout_path, gsk_path_unref);
+}
+
+static gboolean
+parse_dash (GtkCssParser *parser,
+            gpointer      out_dash)
+{
+  GArray *dash;
+  double d;
+
+  /* because CSS does this, too */
+  if (gtk_css_parser_try_ident (parser, "none"))
+    {
+      *((GArray **) out_dash) = NULL;
+      return TRUE;
+    }
+
+  dash = g_array_new (FALSE, FALSE, sizeof (float));
+  do {
+    if (!gtk_css_parser_consume_number (parser, &d))
+      {
+        g_array_free (dash, TRUE);
+        return FALSE;
+      }
+
+    g_array_append_vals (dash, (float[1]) { d }, 1);
+  } while (gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNLESS_NUMBER) ||
+           gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNLESS_INTEGER));
+
+  *((GArray **) out_dash) = dash;
+
+  return TRUE;
+}
+
+static void
+clear_dash (gpointer inout_array)
+{
+  g_clear_pointer ((GArray **) inout_array, g_array_unref);
+}
+
+static gboolean
+parse_enum (GtkCssParser *parser,
+            GType         type,
+            gpointer      out_value)
+{
+  GEnumClass *class;
+  GEnumValue *v;
+  const GtkCssToken *token;
+
+  token = gtk_css_parser_get_token (parser);
+  if (!gtk_css_token_is (token, GTK_CSS_TOKEN_IDENT))
+    {
+      gtk_css_parser_error_syntax (parser, "Expected a valid identifier");
+      return FALSE;
+    }
+
+  class = g_type_class_ref (type);
+
+  v = g_enum_get_value_by_nick (class, token->string.string);
+  if (v == NULL)
+    {
+      gtk_css_parser_error_value (parser, "\"%s\" is not a valid identifier here", token->string.string);
+      g_type_class_unref (class);
+      return FALSE;
+    }
+
+  *(int*)out_value = v->value;
+
+  g_type_class_unref (class);
+
+  gtk_css_parser_consume_token (parser);
+
+  return TRUE;
+}
+
+static gboolean
+parse_fill_rule (GtkCssParser *parser,
+                 gpointer      out_rule)
+{
+  return parse_enum (parser, GSK_TYPE_FILL_RULE, out_rule);
+}
+
+static GskRenderNode *
+parse_fill_node (GtkCssParser *parser)
+{
+  GskRenderNode *child = NULL;
+  GskPath *path = NULL;
+  int rule = GSK_FILL_RULE_WINDING;
+  const Declaration declarations[] = {
+    { "child", parse_node, clear_node, &child },
+    { "path", parse_path, clear_path, &path },
+    { "fill-rule", parse_fill_rule, NULL, &rule },
+  };
+  GskRenderNode *result;
+
+  parse_declarations (parser, declarations, G_N_ELEMENTS (declarations));
+  if (child == NULL)
+    child = create_default_render_node ();
+  if (path == NULL)
+    path = create_default_path ();
+
+  result = gsk_fill_node_new (child, path, rule);
+
+  gsk_path_unref (path);
+
+  gsk_render_node_unref (child);
+
+  return result;
+}
+
+static gboolean
+parse_line_cap (GtkCssParser *parser,
+                gpointer      out)
+{
+  return parse_enum (parser, GSK_TYPE_LINE_CAP, out);
+}
+
+static gboolean
+parse_line_join (GtkCssParser *parser,
+                 gpointer      out)
+{
+  return parse_enum (parser, GSK_TYPE_LINE_JOIN, out);
+}
+
+static GskRenderNode *
+parse_stroke_node (GtkCssParser *parser)
+{
+  GskRenderNode *child = NULL;
+  GskPath *path = NULL;
+  double line_width = 1.0;
+  int line_cap = GSK_LINE_CAP_BUTT;
+  int line_join = GSK_LINE_JOIN_MITER;
+  double miter_limit = 4.0;
+  GArray *dash = NULL;
+  double dash_offset = 0.0;
+  GskStroke *stroke;
+
+  const Declaration declarations[] = {
+    { "child", parse_node, clear_node, &child },
+    { "path", parse_path, clear_path, &path },
+    { "line-width", parse_double, NULL, &line_width },
+    { "line-cap", parse_line_cap, NULL, &line_cap },
+    { "line-join", parse_line_join, NULL, &line_join },
+    { "miter-limit", parse_double, NULL, &miter_limit },
+    { "dash", parse_dash, clear_dash, &dash },
+    { "dash-offset", parse_double, NULL, &dash_offset},
+  };
+  GskRenderNode *result;
+
+  parse_declarations (parser, declarations, G_N_ELEMENTS (declarations));
+  if (child == NULL)
+    child = create_default_render_node ();
+  if (path == NULL)
+    path = create_default_path ();
+
+  stroke = gsk_stroke_new (line_width);
+  gsk_stroke_set_line_cap (stroke, line_cap);
+  gsk_stroke_set_line_join (stroke, line_join);
+  gsk_stroke_set_miter_limit (stroke, miter_limit);
+  if (dash)
+    {
+      gsk_stroke_set_dash (stroke, (float *) dash->data, dash->len);
+      g_array_free (dash, TRUE);
+    }
+  gsk_stroke_set_dash_offset (stroke, dash_offset);
+
+  result = gsk_stroke_node_new (child, path, stroke);
+
+  gsk_path_unref (path);
+  gsk_stroke_free (stroke);
+  gsk_render_node_unref (child);
+
+  return result;
+}
+
 static GskRenderNode *
 parse_shadow_node (GtkCssParser *parser)
 {
@@ -1834,6 +2063,7 @@ parse_node (GtkCssParser *parser,
     { "container", parse_container_node },
     { "cross-fade", parse_cross_fade_node },
     { "debug", parse_debug_node },
+    { "fill", parse_fill_node },
     { "inset-shadow", parse_inset_shadow_node },
     { "linear-gradient", parse_linear_gradient_node },
     { "radial-gradient", parse_radial_gradient_node },
@@ -1845,6 +2075,7 @@ parse_node (GtkCssParser *parser,
     { "repeating-radial-gradient", parse_repeating_radial_gradient_node },
     { "rounded-clip", parse_rounded_clip_node },
     { "shadow", parse_shadow_node },
+    { "stroke", parse_stroke_node },
     { "text", parse_text_node },
     { "texture", parse_texture_node },
     { "transform", parse_transform_node },
@@ -2100,7 +2331,7 @@ append_float_param (Printer    *p,
                     float       value,
                     float       default_value)
 {
-  /* Don't approximate-compare here, better be topo verbose */
+  /* Don't approximate-compare here, better be too verbose */
   if (value == default_value)
     return;
 
@@ -2275,8 +2506,11 @@ append_escaping_newlines (GString    *str,
     len = strcspn (string, "\n");
     g_string_append_len (str, string, len);
     string += len;
-    g_string_append (str, "\\\n");
-    string++;
+    if (*string)
+      {
+        g_string_append (str, "\\\n");
+        string++;
+      }
   } while (*string);
 }
 
@@ -2391,6 +2625,83 @@ gsk_text_node_serialize_glyphs (GskRenderNode *node,
     pango_glyph_string_free (ascii);
 }
 
+static const char *
+enum_to_nick (GType type,
+              int   value)
+{
+  GEnumClass *class;
+  GEnumValue *v;
+
+  class = g_type_class_ref (type);
+  v = g_enum_get_value (class, value);
+  g_type_class_unref (class);
+
+  return v->value_nick;
+}
+
+static void
+append_enum_param (Printer    *p,
+                   const char *param_name,
+                   GType       type,
+                   int         value)
+{
+  _indent (p);
+  g_string_append_printf (p->str, "%s: ", param_name);
+  g_string_append (p->str, enum_to_nick (type, value));
+  g_string_append_c (p->str, ';');
+  g_string_append_c (p->str, '\n');
+}
+
+static void
+append_path_param (Printer    *p,
+                   const char *param_name,
+                   GskPath    *path)
+{
+  char *str, *s;
+
+  _indent (p);
+  g_string_append (p->str, "path: \"\\\n");
+  str = gsk_path_to_string (path);
+  /* Put each command on a new line */
+  for (s = str; *s; s++)
+    {
+      if (*s == ' ' &&
+          (s[1] == 'M' || s[1] == 'C' || s[1] == 'Z' || s[1] == 'L' || s[1] == 'O'))
+        *s = '\n';
+    }
+  append_escaping_newlines (p->str, str);
+  g_string_append (p->str, "\";\n");
+  g_free (str);
+}
+
+static void
+append_dash_param (Printer     *p,
+                   const char  *param_name,
+                   const float *dash,
+                   gsize        n_dash)
+{
+  _indent (p);
+  g_string_append (p->str, "dash: ");
+
+  if (n_dash == 0)
+    {
+      g_string_append (p->str, "none");
+    }
+  else
+    {
+      gsize i;
+
+      string_append_double (p->str, dash[0]);
+      for (i = 1; i < n_dash; i++)
+        {
+          g_string_append_c (p->str, ' ');
+          string_append_double (p->str, dash[i]);
+        }
+    }
+
+  g_string_append (p->str, ";\n");
+}
+
 static void
 render_node_print (Printer       *p,
                    GskRenderNode *node)
@@ -2539,6 +2850,42 @@ render_node_print (Printer       *p,
         append_rounded_rect_param (p, "clip", gsk_rounded_clip_node_get_clip (node));
         append_node_param (p, "child", gsk_rounded_clip_node_get_child (node));
 
+        end_node (p);
+      }
+      break;
+
+    case GSK_FILL_NODE:
+      {
+        start_node (p, "fill");
+
+        append_node_param (p, "child", gsk_fill_node_get_child (node));
+        append_path_param (p, "path", gsk_fill_node_get_path (node));
+        append_enum_param (p, "fill-rule", GSK_TYPE_FILL_RULE, gsk_fill_node_get_fill_rule (node));
+
+        end_node (p);
+      }
+      break;
+
+    case GSK_STROKE_NODE:
+      {
+        const GskStroke *stroke;
+        const float *dash;
+        gsize n_dash;
+
+        start_node (p, "stroke");
+
+        append_node_param (p, "child", gsk_stroke_node_get_child (node));
+        append_path_param (p, "path", gsk_stroke_node_get_path (node));
+
+        stroke = gsk_stroke_node_get_stroke (node);
+        append_float_param (p, "line-width", gsk_stroke_get_line_width (stroke), 0.0f);
+        append_enum_param (p, "line-cap", GSK_TYPE_LINE_CAP, gsk_stroke_get_line_cap (stroke));
+        append_enum_param (p, "line-join", GSK_TYPE_LINE_JOIN, gsk_stroke_get_line_join (stroke));
+        append_float_param (p, "miter-limit", gsk_stroke_get_miter_limit (stroke), 4.0f);
+        dash = gsk_stroke_get_dash (stroke, &n_dash);
+        if (dash)
+          append_dash_param (p, "dash", dash, n_dash);
+        append_float_param (p, "dash-offset", gsk_stroke_get_dash_offset (stroke), 0.0f);
 
         end_node (p);
       }
@@ -3045,3 +3392,4 @@ gsk_render_node_serialize (GskRenderNode *node)
 
   return g_string_free_to_bytes (p.str);
 }
+

gsk/gskrendernodeprivate.h

@@ -29,6 +29,7 @@ struct _GskRenderNode
   graphene_rect_t bounds;
 
   guint prefers_high_depth : 1;
+  guint offscreen_for_opacity : 1;
 };
 
 struct _GskRenderNodeClass
@@ -113,6 +114,10 @@ void             gsk_transform_node_get_translate       (const GskRenderNode *no
                                                          float               *dy);
 gboolean       gsk_render_node_prefers_high_depth       (const GskRenderNode *node);
 
+gboolean       gsk_container_node_is_disjoint           (const GskRenderNode *node);
+
+gboolean       gsk_render_node_use_offscreen_for_opacity (const GskRenderNode *node);
+
 
 G_END_DECLS
 

gsk/gskspline.c

@@ -0,0 +1,208 @@
+/*
+ * Copyright © 2002 University of Southern California
+ *             2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ *          Carl D. Worth <cworth@cworth.org>
+ */
+
+#include "config.h"
+
+#include "gsksplineprivate.h"
+
+#include <math.h>
+
+/* Spline deviation from the circle in radius would be given by:
+
+        error = sqrt (x**2 + y**2) - 1
+
+   A simpler error function to work with is:
+
+        e = x**2 + y**2 - 1
+
+   From "Good approximation of circles by curvature-continuous Bezier
+   curves", Tor Dokken and Morten Daehlen, Computer Aided Geometric
+   Design 8 (1990) 22-41, we learn:
+
+        abs (max(e)) = 4/27 * sin**6(angle/4) / cos**2(angle/4)
+
+   and
+        abs (error) =~ 1/2 * e
+
+   Of course, this error value applies only for the particular spline
+   approximation that is used in _cairo_gstate_arc_segment.
+*/
+static float
+arc_error_normalized (float angle)
+{
+  return 2.0/27.0 * pow (sin (angle / 4), 6) / pow (cos (angle / 4), 2);
+}
+
+static float
+arc_max_angle_for_tolerance_normalized (float tolerance)
+{
+  float angle, error;
+  guint i;
+
+  /* Use table lookup to reduce search time in most cases. */
+  struct {
+    float angle;
+    float error;
+  } table[] = {
+    { G_PI / 1.0,   0.0185185185185185036127 },
+    { G_PI / 2.0,   0.000272567143730179811158 },
+    { G_PI / 3.0,   2.38647043651461047433e-05 },
+    { G_PI / 4.0,   4.2455377443222443279e-06 },
+    { G_PI / 5.0,   1.11281001494389081528e-06 },
+    { G_PI / 6.0,   3.72662000942734705475e-07 },
+    { G_PI / 7.0,   1.47783685574284411325e-07 },
+    { G_PI / 8.0,   6.63240432022601149057e-08 },
+    { G_PI / 9.0,   3.2715520137536980553e-08 },
+    { G_PI / 10.0,  1.73863223499021216974e-08 },
+    { G_PI / 11.0,  9.81410988043554039085e-09 },
+  };
+
+  for (i = 0; i < G_N_ELEMENTS (table); i++)
+    {
+      if (table[i].error < tolerance)
+        return table[i].angle;
+    }
+
+  i++;
+  do {
+    angle = G_PI / i++;
+    error = arc_error_normalized (angle);
+  } while (error > tolerance);
+
+  return angle;
+}
+
+static guint
+arc_segments_needed (float angle,
+                     float radius,
+                     float tolerance)
+{
+  float max_angle;
+
+  /* the error is amplified by at most the length of the
+   * major axis of the circle; see cairo-pen.c for a more detailed analysis
+   * of this. */
+  max_angle = arc_max_angle_for_tolerance_normalized (tolerance / radius);
+
+  return ceil (fabs (angle) / max_angle);
+}
+
+/* We want to draw a single spline approximating a circular arc radius
+   R from angle A to angle B. Since we want a symmetric spline that
+   matches the endpoints of the arc in position and slope, we know
+   that the spline control points must be:
+
+        (R * cos(A), R * sin(A))
+        (R * cos(A) - h * sin(A), R * sin(A) + h * cos (A))
+        (R * cos(B) + h * sin(B), R * sin(B) - h * cos (B))
+        (R * cos(B), R * sin(B))
+
+   for some value of h.
+
+   "Approximation of circular arcs by cubic polynomials", Michael
+   Goldapp, Computer Aided Geometric Design 8 (1991) 227-238, provides
+   various values of h along with error analysis for each.
+
+   From that paper, a very practical value of h is:
+
+        h = 4/3 * R * tan(angle/4)
+
+   This value does not give the spline with minimal error, but it does
+   provide a very good approximation, (6th-order convergence), and the
+   error expression is quite simple, (see the comment for
+   _arc_error_normalized).
+*/
+static gboolean
+gsk_spline_decompose_arc_segment (const graphene_point_t *center,
+                                  float                   radius,
+                                  float                   angle_A,
+                                  float                   angle_B,
+                                  GskSplineAddCurveFunc   curve_func,
+                                  gpointer                user_data)
+{
+  float r_sin_A, r_cos_A;
+  float r_sin_B, r_cos_B;
+  float h;
+
+  r_sin_A = radius * sin (angle_A);
+  r_cos_A = radius * cos (angle_A);
+  r_sin_B = radius * sin (angle_B);
+  r_cos_B = radius * cos (angle_B);
+
+  h = 4.0/3.0 * tan ((angle_B - angle_A) / 4.0);
+
+  return curve_func ((graphene_point_t[4]) {
+                       GRAPHENE_POINT_INIT (
+                         center->x + r_cos_A,
+                         center->y + r_sin_A
+                       ),
+                       GRAPHENE_POINT_INIT (
+                         center->x + r_cos_A - h * r_sin_A,
+                         center->y + r_sin_A + h * r_cos_A
+                       ),
+                       GRAPHENE_POINT_INIT (
+                         center->x + r_cos_B + h * r_sin_B,
+                         center->y + r_sin_B - h * r_cos_B
+                       ),
+                       GRAPHENE_POINT_INIT (
+                         center->x + r_cos_B,
+                         center->y + r_sin_B
+                       )
+                     },
+                     user_data);
+}
+
+gboolean
+gsk_spline_decompose_arc (const graphene_point_t *center,
+                          float                   radius,
+                          float                   tolerance,
+                          float                   start_angle,
+                          float                   end_angle,
+                          GskSplineAddCurveFunc   curve_func,
+                          gpointer                user_data)
+{
+  float step = start_angle - end_angle;
+  guint i, n_segments;
+
+  /* Recurse if drawing arc larger than pi */
+  if (ABS (step) > G_PI)
+    {
+      float mid_angle = (start_angle + end_angle) / 2.0;
+
+      return gsk_spline_decompose_arc (center, radius, tolerance, start_angle, mid_angle, curve_func, user_data)
+          && gsk_spline_decompose_arc (center, radius, tolerance, mid_angle, end_angle, curve_func, user_data);
+    }
+  else if (ABS (step) < tolerance)
+    {
+      return gsk_spline_decompose_arc_segment (center, radius, start_angle, end_angle, curve_func, user_data);
+    }
+
+  n_segments = arc_segments_needed (ABS (step), radius, tolerance);
+  step = (end_angle - start_angle) / n_segments;
+
+  for (i = 0; i < n_segments - 1; i++, start_angle += step)
+    {
+      if (!gsk_spline_decompose_arc_segment (center, radius, start_angle, start_angle + step, curve_func, user_data))
+        return FALSE;
+    }
+  return gsk_spline_decompose_arc_segment (center, radius, start_angle, end_angle, curve_func, user_data);
+}
+

gsk/gsksplineprivate.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_SPLINE_PRIVATE_H__
+#define __GSK_SPLINE_PRIVATE_H__
+
+#include "gskpath.h"
+
+G_BEGIN_DECLS
+
+typedef gboolean (* GskSplineAddCurveFunc) (const graphene_point_t curve[4],
+                                            gpointer               user_data);
+gboolean                gsk_spline_decompose_arc                (const graphene_point_t *center,
+                                                                 float                   radius,
+                                                                 float                   tolerance,
+                                                                 float                   start_angle,
+                                                                 float                   end_angle,
+                                                                 GskSplineAddCurveFunc   curve_func,
+                                                                 gpointer                user_data);
+
+G_END_DECLS
+
+#endif /* __GSK_SPLINE_PRIVATE_H__ */
+

gsk/gskstroke.c

@@ -0,0 +1,458 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gskstrokeprivate.h"
+
+/**
+ * GskStroke:
+ *
+ * A `GskStroke` describes the attributes that are used when stroking a path.
+ */
+
+G_DEFINE_BOXED_TYPE (GskStroke, gsk_stroke,
+                     gsk_stroke_copy,
+                     gsk_stroke_free)
+
+
+/**
+ * gsk_stroke_new:
+ * @line_width: line width of the stroke. Must be > 0
+ *
+ * Creates a new `GskStroke` with the given @line_width.
+ *
+ * Returns: a new `GskStroke`
+ **/
+GskStroke *
+gsk_stroke_new (float line_width)
+{
+  GskStroke *self;
+
+  g_return_val_if_fail (line_width > 0, NULL);
+
+  self = g_new0 (GskStroke, 1);
+
+  self->line_width = line_width;
+  self->line_cap = GSK_LINE_CAP_BUTT;
+  self->line_join = GSK_LINE_JOIN_MITER;
+  self->miter_limit = 4.f; /* following svg */
+
+  return self;
+}
+
+/**
+ * gsk_stroke_copy:
+ * @other: `GskStroke` to copy
+ *
+ * Creates a copy of the given @other stroke.
+ *
+ * Returns: a new `GskStroke`. Use [method@Gsk.Stroke.free] to free it.
+ **/
+GskStroke *
+gsk_stroke_copy (const GskStroke *other)
+{
+  GskStroke *self;
+
+  g_return_val_if_fail (other != NULL, NULL);
+
+  self = g_new (GskStroke, 1);
+
+  gsk_stroke_init_copy (self, other);
+
+  return self;
+}
+
+/**
+ * gsk_stroke_free:
+ * @self: a `GskStroke`
+ *
+ * Frees a `GskStroke`.
+ **/
+void
+gsk_stroke_free (GskStroke *self)
+{
+  if (self == NULL)
+    return;
+
+  gsk_stroke_clear (self);
+
+  g_free (self);
+}
+
+/**
+ * gsk_stroke_to_cairo:
+ * @self: a #GskStroke
+ * @cr: the cairo context to configure
+ *
+ * A helper function that sets the stroke parameters
+ * of @cr from the values found in @self.
+ */
+void
+gsk_stroke_to_cairo (const GskStroke *self,
+                     cairo_t         *cr)
+{
+  cairo_set_line_width (cr, self->line_width);
+
+  /* gcc can optimize that to a direct case. This catches later additions to the enum */
+  switch (self->line_cap)
+    {
+      case GSK_LINE_CAP_BUTT:
+        cairo_set_line_cap (cr, CAIRO_LINE_CAP_BUTT);
+        break;
+      case GSK_LINE_CAP_ROUND:
+        cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
+        break;
+      case GSK_LINE_CAP_SQUARE:
+        cairo_set_line_cap (cr, CAIRO_LINE_CAP_SQUARE);
+        break;
+      default:
+        g_assert_not_reached ();
+        break;
+    }
+
+  /* gcc can optimize that to a direct case. This catches later additions to the enum */
+  switch (self->line_join)
+    {
+      case GSK_LINE_JOIN_MITER:
+      case GSK_LINE_JOIN_MITER_CLIP:
+      case GSK_LINE_JOIN_ARCS:
+        cairo_set_line_join (cr, CAIRO_LINE_JOIN_MITER);
+        break;
+      case GSK_LINE_JOIN_ROUND:
+        cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);
+        break;
+      case GSK_LINE_JOIN_BEVEL:
+        cairo_set_line_join (cr, CAIRO_LINE_JOIN_BEVEL);
+        break;
+      default:
+        g_assert_not_reached ();
+        break;
+    }
+
+  cairo_set_miter_limit (cr, self->miter_limit);
+
+  if (self->dash_length)
+    {
+      gsize i;
+      double *dash = g_newa (double, self->n_dash);
+
+      for (i = 0; i < self->n_dash; i++)
+        {
+          dash[i] = self->dash[i];
+        }
+      cairo_set_dash (cr, dash, self->n_dash, self->dash_offset);
+    }
+  else
+    cairo_set_dash (cr, NULL, 0, 0.0);
+}
+
+/**
+ * gsk_stroke_equal:
+ * @stroke1: the first `GskStroke`
+ * @stroke2: the second `GskStroke`
+ *
+ * Checks if two strokes are identical.
+ *
+ * Returns: %TRUE if the two strokes are equal, %FALSE otherwise
+ **/
+gboolean
+gsk_stroke_equal (gconstpointer stroke1,
+                  gconstpointer stroke2)
+{
+  const GskStroke *self1 = stroke1;
+  const GskStroke *self2 = stroke2;
+
+  if (self1->line_width != self2->line_width ||
+      self1->line_cap != self2->line_cap ||
+      self1->line_join != self2->line_join ||
+      self1->miter_limit != self2->miter_limit)
+    return FALSE;
+
+  if (self1->n_dash != self2->n_dash)
+    return FALSE;
+
+  for (int i = 0; i < self1->n_dash; i++)
+    {
+      if (self1->dash[i] != self2->dash[i])
+        return FALSE;
+    }
+
+  if (self1->dash_offset != self2->dash_offset)
+    return FALSE;
+
+  return TRUE;
+}
+
+/**
+ * gsk_stroke_set_line_width:
+ * @self: a `GskStroke`
+ * @line_width: width of the line in pixels
+ *
+ * Sets the line width to be used when stroking.
+ *
+ * The line width must be > 0.
+ **/
+void
+gsk_stroke_set_line_width (GskStroke *self,
+                           float      line_width)
+{
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (line_width > 0);
+
+  self->line_width = line_width;
+}
+
+/**
+ * gsk_stroke_get_line_width:
+ * @self: a `GskStroke`
+ *
+ * Gets the line width used.
+ *
+ * Returns: The line width
+ **/
+float
+gsk_stroke_get_line_width (const GskStroke *self)
+{
+  g_return_val_if_fail (self != NULL, 0.0);
+
+  return self->line_width;
+}
+
+/**
+ * gsk_stroke_set_line_cap:
+ * @self: a `GskStroke`
+ * @line_cap: the `GskLineCap`
+ *
+ * Sets the line cap to be used when stroking.
+ *
+ * See `GskLineCap` for details.
+ **/
+void
+gsk_stroke_set_line_cap (GskStroke  *self,
+                         GskLineCap  line_cap)
+{
+  g_return_if_fail (self != NULL);
+
+  self->line_cap = line_cap;
+}
+
+/**
+ * gsk_stroke_get_line_cap:
+ * @self: a `GskStroke`
+ *
+ * Gets the line cap used.
+ *
+ * See `GskLineCap` for details.
+ *
+ * Returns: The line cap
+ **/
+GskLineCap
+gsk_stroke_get_line_cap (const GskStroke *self)
+{
+  g_return_val_if_fail (self != NULL, 0.0);
+
+  return self->line_cap;
+}
+
+/**
+ * gsk_stroke_set_line_join:
+ * @self: a `GskStroke`
+ * @line_join: The line join to use
+ *
+ * Sets the line join to be used when stroking.
+ *
+ * See `GskLineJoin` for details.
+ **/
+void
+gsk_stroke_set_line_join (GskStroke   *self,
+                          GskLineJoin  line_join)
+{
+  g_return_if_fail (self != NULL);
+
+  self->line_join = line_join;
+}
+
+/**
+ * gsk_stroke_get_line_join:
+ * @self: a `GskStroke`
+ *
+ * Gets the line join used.
+ *
+ * See `GskLineJoin` for details.
+ *
+ * Returns: The line join
+ **/
+GskLineJoin
+gsk_stroke_get_line_join (const GskStroke *self)
+{
+  g_return_val_if_fail (self != NULL, 0.0);
+
+  return self->line_join;
+}
+
+/**
+ * gsk_stroke_set_miter_limit:
+ * @self: a `GskStroke`
+ * @limit: the miter limit, must be non-negative
+ *
+ * Sets the limit for the distance from the corner where sharp
+ * turns of joins get cut off. The miter limit is in units of
+ * line width.
+ *
+ * For joins of type `GSK_LINE_JOIN_MITER` that exceed the miter
+ * limit, the join gets rendered as if it was of type
+ * `GSK_LINE_JOIN_BEVEL`. For joins of type `GSK_LINE_JOIN_MITER_CLIP`,
+ * the miter is clipped at a distance of half the miter limit.
+ */
+void
+gsk_stroke_set_miter_limit (GskStroke  *self,
+                            float       limit)
+{
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (limit >= 0);
+
+  self->miter_limit = limit;
+}
+
+/**
+ * gsk_stroke_get_miter_limit:
+ * @self: a `GskStroke`
+ *
+ * Returns the miter limit of a `GskStroke`.
+ */
+float
+gsk_stroke_get_miter_limit (const GskStroke *self)
+{
+  g_return_val_if_fail (self != NULL, 4.f);
+
+  return self->miter_limit;
+}
+
+/**
+ * gsk_stroke_set_dash:
+ * @self: a `GskStroke`
+ * @dash: (array length=n_dash) (transfer none) (allow-none): the array of dashes
+ * @n_dash: number of elements in @dash
+ *
+ * Sets the dash pattern to use by this stroke. A dash pattern is specified by
+ * an array of alternating non-negative values. Each value provides the length
+ * of alternate "on" and "off" portions of the stroke.
+ *
+ * Each "on" segment will have caps applied as if the segment were a separate
+ * contour. In particular, it is valid to use an "on" length of 0 with
+ * `GSK_LINE_CAP_ROUND` or `GSK_LINE_CAP_SQUARE` to draw dots or squares along
+ * a path.
+ *
+ * If @n_dash is 0, if all elements in @dash are 0, or if there are negative
+ * values in @dash, then dashing is disabled.
+ *
+ * If @n_dash is 1, an alternating "on" and "off" pattern with the single
+ * dash length provided is assumed.
+ *
+ * If @n_dash is uneven, the dash array will be used with the first element
+ * in @dash defining an "on" or "off" in alternating passes through the array.
+ *
+ * You can specify a starting offset into the dash with [method@Gsk.Stroke.set_dash_offset].
+ **/
+void
+gsk_stroke_set_dash (GskStroke   *self,
+                     const float *dash,
+                     gsize        n_dash)
+{
+  float dash_length;
+  gsize i;
+
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (dash != NULL || n_dash == 0);
+
+  dash_length = 0;
+  for (i = 0; i < n_dash; i++)
+    {
+      if (!(dash[i] >= 0)) /* should catch NaN */
+        {
+          g_critical ("invalid value in dash array at position %zu", i);
+          return;
+        }
+      dash_length += dash[i];
+    }
+
+  self->dash_length = dash_length;
+  g_free (self->dash);
+  self->dash = g_memdup (dash, sizeof (gfloat) * n_dash);
+  self->n_dash = n_dash;
+
+}
+
+/**
+ * gsk_stroke_get_dash:
+ * @self: a `GskStroke`
+ * @n_dash: (out caller-allocates): number of elements
+ *   in the array returned
+ *
+ * Gets the dash array in use or %NULL if dashing is disabled.
+ *
+ * Returns: (array length=n_dash) (transfer none) (allow-none):
+ *   The dash array or %NULL if the dash array is empty.
+ **/
+const float *
+gsk_stroke_get_dash (const GskStroke *self,
+                     gsize           *n_dash)
+{
+  g_return_val_if_fail (self != NULL, NULL);
+  g_return_val_if_fail (n_dash != NULL, NULL);
+
+  *n_dash = self->n_dash;
+
+  return self->dash;
+}
+
+/**
+ * gsk_stroke_set_dash_offset:
+ * @self: a `GskStroke`
+ * @offset: offset into the dash pattern
+ *
+ * Sets the offset into the dash pattern set via [method@Gsk.Stroke.set_dash]
+ * where dashing should begin.
+ *
+ * This is an offset into the length of the path, not an index into
+ * the array values of the dash array.
+ **/
+void
+gsk_stroke_set_dash_offset (GskStroke *self,
+                            float      offset)
+{
+  g_return_if_fail (self != NULL);
+
+  self->dash_offset = offset;
+}
+
+/**
+ * gsk_stroke_get_dash_offset:
+ * @self: a `GskStroke`
+ *
+ * Returns the dash offset of a `GskStroke`.
+ */
+float
+gsk_stroke_get_dash_offset (const GskStroke *self)
+{
+  g_return_val_if_fail (self != NULL, 4.f);
+
+  return self->dash_offset;
+}

gsk/gskstroke.h

@@ -0,0 +1,91 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#ifndef __GSK_STROKE_H__
+#define __GSK_STROKE_H__
+
+#if !defined (__GSK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gsk/gsk.h> can be included directly."
+#endif
+
+
+#include <gsk/gsktypes.h>
+
+G_BEGIN_DECLS
+
+#define GSK_TYPE_STROKE (gsk_stroke_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+GType                   gsk_stroke_get_type                     (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_ALL
+GskStroke *             gsk_stroke_new                          (float                   line_width);
+GDK_AVAILABLE_IN_ALL
+GskStroke *             gsk_stroke_copy                         (const GskStroke        *other);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_free                         (GskStroke              *self);
+
+GDK_AVAILABLE_IN_ALL
+gboolean                gsk_stroke_equal                        (gconstpointer           stroke1,
+                                                                 gconstpointer           stroke2);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_line_width               (GskStroke              *self,
+                                                                 float                   line_width);
+GDK_AVAILABLE_IN_ALL
+float                   gsk_stroke_get_line_width               (const GskStroke        *self);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_line_cap                 (GskStroke              *self,
+                                                                 GskLineCap              line_cap);
+GDK_AVAILABLE_IN_ALL
+GskLineCap              gsk_stroke_get_line_cap                 (const GskStroke        *self);
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_line_join                (GskStroke              *self,
+                                                                 GskLineJoin             line_join);
+GDK_AVAILABLE_IN_ALL
+GskLineJoin             gsk_stroke_get_line_join                (const GskStroke        *self);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_miter_limit              (GskStroke              *self,
+                                                                 float                   limit);
+GDK_AVAILABLE_IN_ALL
+float                   gsk_stroke_get_miter_limit              (const GskStroke        *self);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_dash                     (GskStroke              *self,
+                                                                 const float            *dash,
+                                                                 gsize                   n_dash);
+GDK_AVAILABLE_IN_ALL
+const float *           gsk_stroke_get_dash                     (const GskStroke        *self,
+                                                                 gsize                  *n_dash);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_set_dash_offset              (GskStroke              *self,
+                                                                 float                   offset);
+GDK_AVAILABLE_IN_ALL
+float                   gsk_stroke_get_dash_offset              (const GskStroke        *self);
+
+GDK_AVAILABLE_IN_ALL
+void                    gsk_stroke_to_cairo                     (const GskStroke        *self,
+                                                                 cairo_t                *cr);
+
+
+
+G_END_DECLS
+
+#endif /* __GSK_STROKE_H__ */

gsk/gskstrokeprivate.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+
+#ifndef __GSK_STROKE_PRIVATE_H__
+#define __GSK_STROKE_PRIVATE_H__
+
+#include "gskstroke.h"
+
+G_BEGIN_DECLS
+
+struct _GskStroke
+{
+  float line_width;
+  GskLineCap line_cap;
+  GskLineJoin line_join;
+  float miter_limit;
+
+  float *dash;
+  gsize n_dash;
+  float dash_length; /* sum of all dashes in the array */
+  float dash_offset;
+};
+
+static inline void
+gsk_stroke_init_copy (GskStroke       *stroke,
+                      const GskStroke *other)
+{
+  *stroke = *other;
+
+  stroke->dash = g_memdup (other->dash, stroke->n_dash * sizeof (float));
+}
+
+static inline void
+gsk_stroke_clear (GskStroke *stroke)
+{
+  g_clear_pointer (&stroke->dash, g_free);
+  stroke->n_dash = 0; /* better safe than sorry */
+}
+
+G_END_DECLS
+
+#endif /* __GSK_STROKE_PRIVATE_H__ */
+

gsk/gsktypes.h

@@ -26,7 +26,11 @@
 #include <gdk/gdk.h>
 #include <gsk/gskenums.h>
 
+typedef struct _GskPath                 GskPath;
+typedef struct _GskPathBuilder          GskPathBuilder;
+typedef struct _GskPathMeasure          GskPathMeasure;
 typedef struct _GskRenderer             GskRenderer;
+typedef struct _GskStroke               GskStroke;
 typedef struct _GskTransform            GskTransform;
 
 #endif /* __GSK_TYPES_H__ */

gsk/meson.build

@@ -22,27 +22,41 @@ gsk_private_gl_shaders = [
 ]
 
 gsk_public_sources = files([
-  'gskdiff.c',
   'gskcairorenderer.c',
+  'gskdiff.c',
   'gskglshader.c',
+  'gskpath.c',
+  'gskpathbuilder.c',
+  'gskpathdash.c',
+  'gskpathmeasure.c',
+  'gskpathops.c',
+  'gskpathstroke.c',
   'gskrenderer.c',
   'gskrendernode.c',
   'gskrendernodeimpl.c',
   'gskrendernodeparser.c',
   'gskroundedrect.c',
+  'gskstroke.c',
   'gsktransform.c',
   'gl/gskglrenderer.c',
 ])
 
 gsk_private_sources = files([
+  'gskboundingbox.c',
   'gskcairoblur.c',
+  'gskcontour.c',
+  'gskconvexity.c',
+  'gskcurve.c',
+  'gskcurveintersect.c',
   'gskdebug.c',
   'gskprivate.c',
   'gskprofiler.c',
+  'gskspline.c',
   'gl/gskglattachmentstate.c',
   'gl/gskglbuffer.c',
   'gl/gskglcommandqueue.c',
   'gl/gskglcompiler.c',
+  'gl/gskglprofiler.c',
   'gl/gskgldriver.c',
   'gl/gskglglyphlibrary.c',
   'gl/gskgliconlibrary.c',
@@ -65,9 +79,13 @@ gsk_public_headers = files([
   'gskcairorenderer.h',
   'gskenums.h',
   'gskglshader.h',
+  'gskpath.h',
+  'gskpathbuilder.h',
+  'gskpathmeasure.h',
   'gskrenderer.h',
   'gskrendernode.h',
   'gskroundedrect.h',
+  'gskstroke.h',
   'gsktransform.h',
   'gsktypes.h',
   'gsk-autocleanup.h',

gsk/vulkan/gskvulkanrenderpass.c

@@ -260,6 +260,8 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
     case GSK_RADIAL_GRADIENT_NODE:
     case GSK_REPEATING_RADIAL_GRADIENT_NODE:
     case GSK_CONIC_GRADIENT_NODE:
+    case GSK_FILL_NODE:
+    case GSK_STROKE_NODE:
     default:
       FALLBACK ("Unsupported node '%s'", g_type_name_from_instance ((GTypeInstance *) node));
 

gtk/gtkapplication.c

@@ -68,7 +68,7 @@
  *
  * `GtkApplication` will automatically load menus from the `GtkBuilder`
  * resource located at "gtk/menus.ui", relative to the application's
- * resource base path (see `g_application_set_resource_base_path()`).
+ * resource base path (see [method@Gio.Application.set_resource_base_path]).
  * The menu with the ID "menubar" is taken as the application's
  * menubar. Additional menus (most interesting submenus) can be named
  * and accessed via [method@Gtk.Application.get_menu_by_id] which allows for
@@ -83,8 +83,8 @@
  * resources. See [method@Gtk.IconTheme.add_resource_path] for more
  * information.
  *
- * If there is a resource located at "gtk/help-overlay.ui" which
- * defines a [class@Gtk.ShortcutsWindow] with ID "help_overlay" then
+ * If there is a resource located at `gtk/help-overlay.ui` which
+ * defines a [class@Gtk.ShortcutsWindow] with ID `help_overlay` then
  * `GtkApplication` associates an instance of this shortcuts window with
  * each [class@Gtk.ApplicationWindow] and sets up the keyboard accelerator
  * <kbd>Control</kbd>+<kbd>?</kbd> to open it. To create a menu item that

gtk/gtkbinlayout.c

@@ -38,7 +38,7 @@ struct _GtkBinLayout
   GtkLayoutManager parent_instance;
 };
 
-G_DEFINE_FINAL_TYPE (GtkBinLayout, gtk_bin_layout, GTK_TYPE_LAYOUT_MANAGER)
+G_DEFINE_TYPE (GtkBinLayout, gtk_bin_layout, GTK_TYPE_LAYOUT_MANAGER)
 
 static void
 gtk_bin_layout_measure (GtkLayoutManager *layout_manager,

gtk/gtkbookmarklist.c

@@ -117,8 +117,8 @@ static void     bookmark_file_changed (GFileMonitor       *monitor,
 static void gtk_bookmark_list_set_filename (GtkBookmarkList *self,
                                                 const char         *filename);
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkBookmarkList, gtk_bookmark_list, G_TYPE_OBJECT,
-                               G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_bookmark_list_model_init))
+G_DEFINE_TYPE_WITH_CODE (GtkBookmarkList, gtk_bookmark_list, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_bookmark_list_model_init))
 
 static void
 gtk_bookmark_list_set_property (GObject      *object,

gtk/gtkboolfilter.c

@@ -46,7 +46,7 @@ enum {
   NUM_PROPERTIES
 };
 
-G_DEFINE_FINAL_TYPE (GtkBoolFilter, gtk_bool_filter, GTK_TYPE_FILTER)
+G_DEFINE_TYPE (GtkBoolFilter, gtk_bool_filter, GTK_TYPE_FILTER)
 
 static GParamSpec *properties[NUM_PROPERTIES] = { NULL, };
 
@@ -106,7 +106,7 @@ gtk_bool_filter_set_property (GObject      *object,
     }
 }
 
-static void
+static void 
 gtk_bool_filter_get_property (GObject     *object,
                               guint        prop_id,
                               GValue      *value,

gtk/gtkboxlayout.c

@@ -58,8 +58,8 @@ struct _GtkBoxLayout
   GtkBaselinePosition baseline_position;
 };
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkBoxLayout, gtk_box_layout, GTK_TYPE_LAYOUT_MANAGER,
-                               G_IMPLEMENT_INTERFACE (GTK_TYPE_ORIENTABLE, NULL))
+G_DEFINE_TYPE_WITH_CODE (GtkBoxLayout, gtk_box_layout, GTK_TYPE_LAYOUT_MANAGER,
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_ORIENTABLE, NULL))
 
 enum {
   PROP_HOMOGENEOUS = 1,
@@ -342,7 +342,7 @@ distribute_remaining_size (GtkRequestedSize *sizes,
       else
         max = test;
     }
-
+    
   return available - total_size;
 }
 

gtk/gtkcenterlayout.c

@@ -54,7 +54,7 @@ struct _GtkCenterLayout
   };
 };
 
-G_DEFINE_FINAL_TYPE (GtkCenterLayout, gtk_center_layout, GTK_TYPE_LAYOUT_MANAGER)
+G_DEFINE_TYPE (GtkCenterLayout, gtk_center_layout, GTK_TYPE_LAYOUT_MANAGER)
 
 static int
 get_spacing (GtkCenterLayout *self,

gtk/gtkconstraint.c

@@ -60,7 +60,7 @@ enum {
 
 static GParamSpec *obj_props[N_PROPERTIES];
 
-G_DEFINE_FINAL_TYPE (GtkConstraint, gtk_constraint, G_TYPE_OBJECT)
+G_DEFINE_TYPE (GtkConstraint, gtk_constraint, G_TYPE_OBJECT)
 
 static void
 gtk_constraint_set_property (GObject      *gobject,

gtk/gtkconstraintguide.c

@@ -59,7 +59,7 @@ typedef enum {
 } GuideValue;
 
 struct _GtkConstraintGuide
-{
+{ 
   GObject parent_instance;
 
   char *name;
@@ -104,9 +104,9 @@ gtk_constraint_guide_constraint_target_iface_init (GtkConstraintTargetInterface
 {
 }
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkConstraintGuide, gtk_constraint_guide, G_TYPE_OBJECT,
-                               G_IMPLEMENT_INTERFACE (GTK_TYPE_CONSTRAINT_TARGET,
-                                                      gtk_constraint_guide_constraint_target_iface_init))
+G_DEFINE_TYPE_WITH_CODE (GtkConstraintGuide, gtk_constraint_guide, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_CONSTRAINT_TARGET,
+                                                gtk_constraint_guide_constraint_target_iface_init))
 
 static void
 gtk_constraint_guide_init (GtkConstraintGuide *guide)

gtk/gtkconstraintlayout.c

@@ -266,7 +266,7 @@ struct _GtkConstraintLayout
   GListStore *guides_observer;
 };
 
-G_DEFINE_FINAL_TYPE (GtkConstraintLayoutChild, gtk_constraint_layout_child, GTK_TYPE_LAYOUT_CHILD)
+G_DEFINE_TYPE (GtkConstraintLayoutChild, gtk_constraint_layout_child, GTK_TYPE_LAYOUT_CHILD)
 
 GtkConstraintSolver *
 gtk_constraint_layout_get_solver (GtkConstraintLayout *self)
@@ -537,8 +537,8 @@ gtk_constraint_layout_child_init (GtkConstraintLayoutChild *self)
 
 static void gtk_buildable_interface_init (GtkBuildableIface *iface);
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkConstraintLayout, gtk_constraint_layout, GTK_TYPE_LAYOUT_MANAGER,
-                               G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE, gtk_buildable_interface_init))
+G_DEFINE_TYPE_WITH_CODE (GtkConstraintLayout, gtk_constraint_layout, GTK_TYPE_LAYOUT_MANAGER,
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE, gtk_buildable_interface_init))
 
 static void
 gtk_constraint_layout_finalize (GObject *gobject)

gtk/gtkcssnumbervalue.c

@@ -69,11 +69,18 @@ gtk_css_calc_value_new_from_array (GtkCssValue **values,
   return result;
 }
 
-
 static void
-gtk_css_value_number_free (GtkCssValue *value)
+gtk_css_value_number_free (GtkCssValue *number)
 {
-  g_slice_free (GtkCssValue, value);
+  if (number->type == TYPE_CALC)
+    {
+      const guint n_terms = number->calc.n_terms;
+
+      for (guint i = 0; i < n_terms; i++)
+        _gtk_css_value_unref (number->calc.terms[i]);
+    }
+
+  g_slice_free (GtkCssValue, number);
 }
 
 static double

gtk/gtkcustomfilter.c

@@ -38,7 +38,7 @@ struct _GtkCustomFilter
   GDestroyNotify user_destroy;
 };
 
-G_DEFINE_FINAL_TYPE (GtkCustomFilter, gtk_custom_filter, GTK_TYPE_FILTER)
+G_DEFINE_TYPE (GtkCustomFilter, gtk_custom_filter, GTK_TYPE_FILTER)
 
 static gboolean
 gtk_custom_filter_match (GtkFilter *filter,

gtk/gtkcustomlayout.c

@@ -22,7 +22,7 @@ struct _GtkCustomLayout
   GtkCustomAllocateFunc allocate_func;
 };
 
-G_DEFINE_FINAL_TYPE (GtkCustomLayout, gtk_custom_layout, GTK_TYPE_LAYOUT_MANAGER)
+G_DEFINE_TYPE (GtkCustomLayout, gtk_custom_layout, GTK_TYPE_LAYOUT_MANAGER)
 
 static GtkSizeRequestMode
 gtk_custom_layout_get_request_mode (GtkLayoutManager *manager,

gtk/gtkcustomsorter.c

@@ -39,7 +39,7 @@ struct _GtkCustomSorter
   GDestroyNotify user_destroy;
 };
 
-G_DEFINE_FINAL_TYPE (GtkCustomSorter, gtk_custom_sorter, GTK_TYPE_SORTER)
+G_DEFINE_TYPE (GtkCustomSorter, gtk_custom_sorter, GTK_TYPE_SORTER)
 
 static GtkOrdering
 gtk_custom_sorter_compare (GtkSorter *sorter,

gtk/gtkdirectorylist.c

@@ -144,8 +144,8 @@ gtk_directory_list_model_init (GListModelInterface *iface)
   iface->get_item = gtk_directory_list_get_item;
 }
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkDirectoryList, gtk_directory_list, G_TYPE_OBJECT,
-                               G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_directory_list_model_init))
+G_DEFINE_TYPE_WITH_CODE (GtkDirectoryList, gtk_directory_list, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL, gtk_directory_list_model_init))
 
 static void
 gtk_directory_list_set_property (GObject      *object,

gtk/gtkdragicon.c

@@ -79,11 +79,11 @@ static GParamSpec *properties[LAST_ARG] = { NULL, };
 static void gtk_drag_icon_root_init   (GtkRootInterface *iface);
 static void gtk_drag_icon_native_init (GtkNativeInterface *iface);
 
-G_DEFINE_FINAL_TYPE_WITH_CODE (GtkDragIcon, gtk_drag_icon, GTK_TYPE_WIDGET,
-                               G_IMPLEMENT_INTERFACE (GTK_TYPE_NATIVE,
-                                                      gtk_drag_icon_native_init)
-                               G_IMPLEMENT_INTERFACE (GTK_TYPE_ROOT,
-                                                      gtk_drag_icon_root_init))
+G_DEFINE_TYPE_WITH_CODE (GtkDragIcon, gtk_drag_icon, GTK_TYPE_WIDGET,
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_NATIVE,
+                                                gtk_drag_icon_native_init)
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_ROOT,
+                                                gtk_drag_icon_root_init))
 
 static GdkDisplay *
 gtk_drag_icon_root_get_display (GtkRoot *self)