Pencil in the no-LUT approach

If we don't use a LUT, we have to handle the
one curve the point in question falls in every
time, which is some overhead, but it lets us
compute precise values.

LOG

@@ -0,0 +1,150 @@
+TAP version 13
+# random seed: R02S22611f6aefc1121b0ab2dc5286960449
+# GLib-GIO-DEBUG: _g_io_module_get_default: Found default implementation dconf (DConfSettingsBackend) for ‘gsettings-backend’
+# GLib-GIO-DEBUG: Using cross-namespace EXTERNAL authentication (this will deadlock if server is GDBus < 2.73.3)
+# GLib-GIO-DEBUG: Using cross-namespace EXTERNAL authentication (this will deadlock if server is GDBus < 2.73.3)
+1..1
+# Start of ops tests
+# testcase 0 op 0
+collecting# 
+    Cubic 0: # M 100.000000 100.000000 C 150.000000 100.000000 200.000000 100.000000 250.000000 100.000000 
+    Cubic 1: # M 250.000000 100.000000 C 300.000000 100.000000 350.000000 100.000000 400.000000 100.000000 
+    Line 2: # M 400 100 L 200 300 
+    Line 3: # M 200 300 L 100 100 
+    Cubic 4: # M 200.000000 100.000000 C 250.000000 100.000000 300.000000 100.000000 350.000000 100.000000 
+    Cubic 5: # M 350.000000 100.000000 C 400.000000 100.000000 450.000000 100.000000 500.000000 100.000000 
+    Line 6: # M 500 100 L 300 300 
+    Line 7: # M 300 300 L 200 100 
+splitting# 
+1 intersections between Cubic 0 and Cubic 1# 
+1 intersections between Cubic 0 and Line 3# 
+9 intersections between Cubic 0 and Cubic 4# 
+# split Cubic 0.0 from Cubic 0 at 0.666666: M 100.000000 100.000000 C 133.333298 100.000000 166.666595 100.000000 199.999893 100.000000
+split Cubic 0.1 from Cubic 0 at 0.666666: M 199.999893 100.000000 C 216.666595 100.000000 233.333298 100.000000 250.000000 100.000000split Cubic 0.4 from Cubic 0 at 0.00600814: M 200.300323 100.000000 C 216.866882 100.000000 233.433441 100.000000 250.000000 100.000000split Cubic 0.7 from Cubic 0 at 0.00604445: M 200.600708 100.000000 C 217.067139 100.000000 233.533569 100.000000 250.000000 100.000000# split Cubic 4.9 from Cubic 4 at 0.00533867: M 200.800812 100.000000 C 250.533875 100.000000 300.266937 100.000000 350.000000 100.000000
+1 intersections between Cubic 0.1 and Line 7# 
+1 intersections between Cubic 1 and Line 2# 
+9 intersections between Cubic 1 and Cubic 4.9# 
+split Cubic 1.9 from Cubic 1 at 0.00534248: M 250.801361 100.000000 C 300.534241 100.000000 350.267120 100.000000 400.000000 100.000000# split Cubic 4.9.0 from Cubic 4.9 at 0.329756: M 200.800812 100.000000 C 217.200577 100.000000 233.600342 100.000000 250.000122 100.000000
+# split Cubic 4.9.1 from Cubic 4.9 at 0.329756: M 250.000122 100.000000 C 283.333435 100.000000 316.666718 100.000000 350.000000 100.000000
+# split Cubic 4.9.6 from Cubic 4.9 at 0.00500283: M 250.500412 100.000000 C 283.666931 100.000000 316.833466 100.000000 350.000000 100.000000
+9 intersections between Cubic 1.9 and Cubic 5# 
+# split Cubic 1.9.0 from Cubic 1.9 at 0.664877: M 250.801361 100.000000 C 283.867615 100.000000 316.933868 100.000000 350.000122 100.000000
+split Cubic 1.9.1 from Cubic 1.9 at 0.664877: M 350.000122 100.000000 C 366.666748 100.000000 383.333374 100.000000 400.000000 100.000000split Cubic 1.9.4 from Cubic 1.9 at 0.00601021: M 350.300598 100.000000 C 366.867065 100.000000 383.433533 100.000000 400.000000 100.000000split Cubic 1.9.7 from Cubic 1.9 at 0.00604655: M 350.601074 100.000000 C 367.067383 100.000000 383.533691 100.000000 400.000000 100.000000# split Cubic 5.9 from Cubic 5 at 0.00534248: M 350.801361 100.000000 C 400.534241 100.000000 450.267120 100.000000 500.000000 100.000000
+1 intersections between Line 2 and Line 3# 
+1 intersections between Line 2 and Line 7# 
+# split Line 2.0 from Line 2 at 0.666667: M 400 100 L 266.667 233.333
+split Line 2.1 from Line 2 at 0.666667: M 266.667 233.333 L 200 300# split Line 7.0 from Line 7 at 0.333333: M 300 300 L 266.667 233.333
+# split Line 7.1 from Line 7 at 0.333333: M 266.667 233.333 L 200 100
+1 intersections between Cubic 4 and Cubic 4.9.0# 
+1 intersections between Cubic 4 and Line 7.1# 
+1 intersections between Cubic 4.9.0 and Cubic 4.9.1# 
+1 intersections between Cubic 4.9.1 and Cubic 4.9.6# 
+1 intersections between Cubic 4.9.6 and Cubic 5# 
+1 intersections between Cubic 5 and Cubic 5.9# 
+1 intersections between Cubic 5.9 and Line 6# 
+1 intersections between Line 6 and Line 7.0# 
+    Cubic 0.0: # M 100.000000 100.000000 C 133.333298 100.000000 166.666595 100.000000 199.999893 100.000000 
+    Cubic 0.1: # M 199.999893 100.000000 C 200.100037 100.000000 200.200180 100.000000 200.300323 100.000000 
+    Cubic 0.4: # M 200.300323 100.000000 C 200.400452 100.000000 200.500580 100.000000 200.600708 100.000000 
+    Cubic 0.7: # M 200.600708 100.000000 C 217.067139 100.000000 233.533569 100.000000 250.000000 100.000000 
+    Cubic 1: # M 250.000000 100.000000 C 250.267120 100.000000 250.534241 100.000000 250.801361 100.000000 
+    Cubic 1.9.0: # M 250.801361 100.000000 C 283.867615 100.000000 316.933868 100.000000 350.000122 100.000000 
+    Cubic 1.9.1: # M 350.000122 100.000000 C 350.100281 100.000000 350.200439 100.000000 350.300598 100.000000 
+    Cubic 1.9.4: # M 350.300598 100.000000 C 350.400757 100.000000 350.500916 100.000000 350.601074 100.000000 
+    Cubic 1.9.7: # M 350.601074 100.000000 C 367.067383 100.000000 383.533691 100.000000 400.000000 100.000000 
+    Line 2.0: # M 400 100 L 266.667 233.333 
+    Line 2.1: # M 266.667 233.333 L 200 300 
+    Line 3: # M 200 300 L 100 100 
+    Cubic 4: # M 200.000000 100.000000 C 200.266937 100.000000 200.533875 100.000000 200.800812 100.000000 
+    Cubic 4.9.0: # M 200.800812 100.000000 C 217.200577 100.000000 233.600342 100.000000 250.000122 100.000000 
+    Cubic 4.9.1: # M 250.000122 100.000000 C 250.166885 100.000000 250.333649 100.000000 250.500412 100.000000 
+    Cubic 4.9.6: # M 250.500412 100.000000 C 283.666931 100.000000 316.833466 100.000000 350.000000 100.000000 
+    Cubic 5: # M 350.000000 100.000000 C 350.267120 100.000000 350.534241 100.000000 350.801361 100.000000 
+    Cubic 5.9: # M 350.801361 100.000000 C 400.534241 100.000000 450.267120 100.000000 500.000000 100.000000 
+    Line 6: # M 500 100 L 300 300 
+    Line 7.0: # M 300 300 L 266.667 233.333 
+    Line 7.1: # M 266.667 233.333 L 200 100 
+classifying# 
+ 01 Cubic 0.0: # M 100.000000 100.000000 C 133.333298 100.000000 166.666595 100.000000 199.999893 100.000000 
+[11 Cubic 0.7: # M 200.600708 100.000000 C 217.067139 100.000000 233.533569 100.000000 250.000000 100.000000 ]
+[11 Cubic 1.9.0: # M 250.801361 100.000000 C 283.867615 100.000000 316.933868 100.000000 350.000122 100.000000 ]
+[11 Cubic 1.9.7: # M 350.601074 100.000000 C 367.067383 100.000000 383.533691 100.000000 400.000000 100.000000 ]
+[11 Line 2.0: # M 400 100 L 266.667 233.333 ]
+ 01 Line 2.1: # M 266.667 233.333 L 200 300 
+ 01 Line 3: # M 200 300 L 100 100 
+[11 Cubic 4: # M 200.000000 100.000000 C 200.266937 100.000000 200.533875 100.000000 200.800812 100.000000 ]
+[11 Cubic 4.9.0: # M 200.800812 100.000000 C 217.200577 100.000000 233.600342 100.000000 250.000122 100.000000 ]
+[11 Cubic 4.9.6: # M 250.500412 100.000000 C 283.666931 100.000000 316.833466 100.000000 350.000000 100.000000 ]
+[11 Cubic 5: # M 350.000000 100.000000 C 350.267120 100.000000 350.534241 100.000000 350.801361 100.000000 ]
+ 01 Cubic 5.9: # M 350.801361 100.000000 C 400.534241 100.000000 450.267120 100.000000 500.000000 100.000000 
+ 01 Line 6: # M 500 100 L 300 300 
+ 01 Line 7.0: # M 300 300 L 266.667 233.333 
+[11 Line 7.1: # M 266.667 233.333 L 200 100 ]
+fixups# 
+# found 3 bad nodes
+# split Cubic 0/Cubic 4 BAD 200.600723 100.000000
+# 	[11 Line 7.1 ] 116.565
+# 	[11 Cubic 0.7 ] 180
+# 	[11 Cubic 4 ] 180
+# 	[11 Cubic 4 ] 180
+# 	[11 Cubic 4.9.0 ] 180
+# 	>01 Cubic 0.0  360
+# split Cubic 1/Cubic 4.9 BAD 250.801376 100.000000
+# 	[11 Cubic 1.9.0 ] 180
+# 	[11 Cubic 4.9.6 ] 180
+# 	[11 Cubic 0.7 ] 360
+# 	[11 Cubic 4.9.0 ] 360
+# split Cubic 1.9/Cubic 5 BAD 350.601105 100.000000
+# 	[11 Cubic 1.9.7 ] 180
+# 	[11 Cubic 5 ] 180
+# 	[11 Cubic 5 ] 180
+# 	<01 Cubic 5.9  180
+# 	[11 Cubic 1.9.0 ] 360
+# 	[11 Cubic 4.9.6 ] 360
+reassembling# 
+start new contour Cubic 0.0# 
+# Cubic 0.0 ends at: 
+# start 0 100.000000 100.000000
+# 	>01 Line 3  116.565
+# 	(10 Cubic 0.0 ) 180
+picking cw# 
+append Line 3# 
+# Line 3 ends at: 
+# end 2 200.000000 300.000000
+# 	>01 Line 2.1  225
+# 	(10 Line 3 ) 296.565
+picking cw# 
+append Line 2.1# 
+# Line 2.1 ends at: 
+# split Line 2/Line 7 266.666656 233.333344
+# 	(10 Line 2.1 ) 45
+# 	>01 Line 7.0  116.565
+# 	[11 Line 2.0 ] 225
+# 	[11 Line 7.1 ] 296.565
+picking cw# 
+append Line 7.0# 
+# Line 7.0 ends at: 
+# end 6 300.000000 300.000000
+# 	>01 Line 6  225
+# 	(10 Line 7.0 ) 296.565
+picking cw# 
+append Line 6# 
+# Line 6 ends at: 
+# end 5 500.000000 100.000000
+# 	(10 Line 6 ) 45
+# 	>01 Cubic 5.9  360
+picking cw# 
+append Cubic 5.9# 
+# Cubic 5.9 ends at: 
+# split Cubic 1.9/Cubic 5 BAD 350.601105 100.000000
+# 	[11 Cubic 1.9.7 ] 180
+# 	[11 Cubic 5 ] 180
+# 	[11 Cubic 5 ] 180
+# 	(10 Cubic 5.9 ) 180
+# 	[11 Cubic 1.9.0 ] 360
+# 	[11 Cubic 4.9.6 ] 360
+picking cw# 
+**
+ERROR:../testsuite/gsk/path-ops.c:359:test_ops_simple: assertion failed (s == tests[i].out): ("M 354.60110473632812 100 A 4 4 0 0 0 346.60110473632812 100 A 4 4 0 0 0 354.60110473632812 100 z M 252.80137634277344 100 A 2 2 0 0 0 248.80137634277344 100 A 2 2 0 0 0 252.80137634277344 100 z M 204.60072326660156 100 A 4 4 0 0 0 196.60072326660156 100 A 4 4 0 0 0 204.60072326660156 100 z" == "M 100 100 z")
+not ok /ops/simple - ERROR:../testsuite/gsk/path-ops.c:359:test_ops_simple: assertion failed (s == tests[i].out): ("M 354.60110473632812 100 A 4 4 0 0 0 346.60110473632812 100 A 4 4 0 0 0 354.60110473632812 100 z M 252.80137634277344 100 A 2 2 0 0 0 248.80137634277344 100 A 2 2 0 0 0 252.80137634277344 100 z M 204.60072326660156 100 A 4 4 0 0 0 196.60072326660156 100 A 4 4 0 0 0 204.60072326660156 100 z" == "M 100 100 z")
+Bail out!

demos/gtk-demo/demo.gresource.xml

@@ -336,6 +336,7 @@
     <file>panes.c</file>
     <file>password_entry.c</file>
     <file>path_fill.c</file>
+    <file>path_text.c</file>
     <file>peg_solitaire.c</file>
     <file>pickers.c</file>
     <file>printing.c</file>
@@ -421,6 +422,9 @@
   <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/meson.build

@@ -73,6 +73,7 @@ demos = files([
   'panes.c',
   'password_entry.c',
   'path_fill.c',
+  'path_text.c',
   'peg_solitaire.c',
   'pickers.c',
   'printing.c',

demos/gtk-demo/path_text.c

@@ -0,0 +1,604 @@
+/* Path/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,
+                       graphene_point_t *out_offset)
+{
+  PangoLayout *layout;
+  PangoFontDescription *desc;
+  GskPathBuilder *builder;
+  GskPath *result;
+
+  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);
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_layout (builder, layout);
+  result = gsk_path_builder_free_to_path (builder);
+
+  if (out_offset)
+    graphene_point_init (out_offset, 0, - pango_layout_get_baseline (layout) / (double) PANGO_SCALE);
+  g_object_unref (layout);
+
+  return result;
+}
+
+typedef struct
+{
+  GskPathMeasure *measure;
+  GskPathBuilder *builder;
+  graphene_point_t offset;
+  double scale;
+} GtkPathTransform;
+
+static void
+gtk_path_transform_point (GskPathMeasure         *measure,
+                          const graphene_point_t *pt,
+                          const graphene_point_t *offset,
+                          float                   scale,
+                          graphene_point_t       *res)
+{
+  graphene_vec2_t tangent;
+  GskPathPoint point;
+
+  if (gsk_path_measure_get_point (measure, (pt->x + offset->x) * scale, &point))
+    {
+      GskPath *path = gsk_path_measure_get_path (measure);
+
+      gsk_path_point_get_position (path, &point, res);
+      gsk_path_point_get_tangent (path, &point, GSK_PATH_END, &tangent);
+
+      res->x -= (pt->y + offset->y) * scale * graphene_vec2_get_y (&tangent);
+      res->y += (pt->y + offset->y) * scale * graphene_vec2_get_x (&tangent);
+    }
+}
+
+static gboolean
+gtk_path_transform_op (GskPathOperation        op,
+                       const graphene_point_t *pts,
+                       gsize                   n_pts,
+                       gpointer                data)
+{
+  GtkPathTransform *transform = data;
+
+  switch (op)
+  {
+    case GSK_PATH_MOVE:
+      {
+        graphene_point_t res;
+        gtk_path_transform_point (transform->measure, &pts[0], &transform->offset, 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->offset, transform->scale, &res);
+        gsk_path_builder_line_to (transform->builder, res.x, res.y);
+      }
+      break;
+
+    case GSK_PATH_QUAD:
+      {
+        graphene_point_t res[2];
+        gtk_path_transform_point (transform->measure, &pts[1], &transform->offset, transform->scale, &res[0]);
+        gtk_path_transform_point (transform->measure, &pts[2], &transform->offset, transform->scale, &res[1]);
+        gsk_path_builder_quad_to (transform->builder, res[0].x, res[0].y, res[1].x, res[1].y);
+      }
+      break;
+
+    case GSK_PATH_CUBIC:
+      {
+        graphene_point_t res[3];
+        gtk_path_transform_point (transform->measure, &pts[1], &transform->offset, transform->scale, &res[0]);
+        gtk_path_transform_point (transform->measure, &pts[2], &transform->offset, transform->scale, &res[1]);
+        gtk_path_transform_point (transform->measure, &pts[3], &transform->offset, transform->scale, &res[2]);
+        gsk_path_builder_cubic_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_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,
+                    const graphene_point_t *offset)
+{
+  GtkPathTransform transform = { measure, gsk_path_builder_new (), *offset };
+  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, -1, 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;
+  graphene_point_t offset;
+
+  gtk_path_widget_clear_text_path (self);
+
+  if (self->line_measure == NULL)
+    return;
+
+  path = create_path_from_text (GTK_WIDGET (self), self->text, &offset);
+  self->text_path = gtk_path_transform (self->line_measure, path, &offset);
+
+  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_cubic_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, 0.6 }, &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)
+    {
+      GskPathBuilder *builder;
+
+      /* 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);
+
+      /* 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);
+    }
+
+  if (self->line_closest >= 0)
+    {
+      GskPathBuilder *builder;
+      GskPathPoint point;
+      graphene_point_t closest;
+
+      builder = gsk_path_builder_new ();
+      if (gsk_path_measure_get_point (self->line_measure, self->line_closest, &point))
+        {
+          gsk_path_point_get_position (self->line_path, &point, &closest);
+          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);
+        }
+    }
+}
+
+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)
+{
+  GskPathPoint point;
+  graphene_point_t pos;
+
+  if (gsk_path_get_closest_point (gsk_path_measure_get_path (self->line_measure),
+                                  &GRAPHENE_POINT_INIT (x, y),
+                                  INFINITY,
+                                  &point))
+    {
+      gsk_path_point_get_position (self->line_path, &point, &pos);
+      self->line_closest = graphene_point_distance (&pos, &GRAPHENE_POINT_INIT (x, y), NULL, 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_window_present (GTK_WINDOW (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>

gdk/win32/gdkevents-win32.c

@@ -2857,7 +2857,10 @@ gdk_event_translate (MSG *msg,
       break;
 
     case WM_SYSCOMMAND:
-      switch (msg->wParam)
+      /* From: https://learn.microsoft.com/en-us/windows/win32/menurc/wm-syscommand?redirectedfrom=MSDN
+       * To obtain the correct result when testing the value of wParam,
+       * an application must combine the value 0xFFF0 with the wParam value by using the bitwise AND operator. */
+      switch (msg->wParam & 0xFFF0)
 	{
 	case SC_MINIMIZE:
 	case SC_RESTORE:
@@ -2964,6 +2967,14 @@ gdk_event_translate (MSG *msg,
                   windowpos = (WINDOWPOS *) msg->lParam;
                   windowpos->cx = our_mmi.ptMaxSize.x;
                   windowpos->cy = our_mmi.ptMaxSize.y;
+
+                  if (!_gdk_win32_surface_lacks_wm_decorations (window) &&
+                      !(windowpos->flags & SWP_NOCLIENTSIZE) &&
+                      window->width == impl->next_layout.configured_width &&
+                      window->height == impl->next_layout.configured_height)
+                    {
+                      impl->inhibit_configure = TRUE;
+                    }
                 }
 
               impl->maximizing = FALSE;

gdk/win32/gdksurface-win32.c

@@ -1230,18 +1230,11 @@ get_effective_window_decorations (GdkSurface       *window,
 
       *decoration |= GDK_DECOR_MINIMIZE;
 
-      return TRUE;
-    }
-  else if (impl->hint_flags & GDK_HINT_MAX_SIZE)
-    {
-      *decoration = GDK_DECOR_ALL | GDK_DECOR_MAXIMIZE;
-      *decoration |= GDK_DECOR_MINIMIZE;
-
       return TRUE;
     }
   else
     {
-      *decoration = (GDK_DECOR_ALL | GDK_DECOR_MINIMIZE | GDK_DECOR_MAXIMIZE);
+      *decoration = GDK_DECOR_ALL;
       return TRUE;
     }
 

gsk/gsk.h

@@ -22,6 +22,7 @@
 #include <gsk/gskenums.h>
 #include <gsk/gskpath.h>
 #include <gsk/gskpathbuilder.h>
+#include <gsk/gskpathmeasure.h>
 #include <gsk/gskpathpoint.h>
 #include <gsk/gskrenderer.h>
 #include <gsk/gskrendernode.h>

gsk/gskcontour.c

@@ -61,6 +61,7 @@ struct _GskContourClass
   GskContour *          (* reverse)             (const GskContour       *contour);
   int                   (* get_winding)         (const GskContour       *contour,
                                                  const graphene_point_t *point);
+  gsize                 (* get_n_points)        (const GskContour       *contour);
   gboolean              (* get_closest_point)   (const GskContour       *contour,
                                                  const graphene_point_t *point,
                                                  float                   threshold,
@@ -76,6 +77,23 @@ struct _GskContourClass
   float                 (* get_curvature)       (const GskContour       *contour,
                                                  GskRealPathPoint       *point,
                                                  graphene_point_t       *center);
+  void                  (* add_segment)         (const GskContour       *contour,
+                                                 GskPathBuilder         *builder,
+                                                 gboolean                emit_move_to,
+                                                 GskRealPathPoint       *start,
+                                                 GskRealPathPoint       *end);
+  gpointer              (* init_measure)        (const GskContour       *contour,
+                                                 float                   tolerance,
+                                                 float                  *out_length);
+  void                  (* free_measure)        (const GskContour       *contour,
+                                                 gpointer                measure_data);
+  void                  (* get_point)           (const GskContour       *contour,
+                                                 gpointer                measure_data,
+                                                 float                   offset,
+                                                 GskRealPathPoint       *result);
+  float                 (* get_distance)        (const GskContour       *contour,
+                                                 GskRealPathPoint       *point,
+                                                 gpointer                measure_data);
 };
 
 /* {{{ Utilities */
@@ -224,6 +242,38 @@ gsk_standard_contour_reverse (const GskContour *contour)
   return res;
 }
 
+static int
+gsk_standard_contour_get_winding (const GskContour       *contour,
+                                  const graphene_point_t *point)
+{
+  GskStandardContour *self = (GskStandardContour *) contour;
+  int winding = 0;
+
+  for (gsize i = 0; i < self->n_ops; i++)
+    {
+      GskCurve c;
+
+      if (gsk_pathop_op (self->ops[i]) == GSK_PATH_MOVE)
+        continue;
+
+      gsk_curve_init (&c, self->ops[i]);
+      winding += gsk_curve_get_crossing (&c, point);
+    }
+
+  if ((self->flags & GSK_PATH_CLOSED) == 0)
+    {
+      GskCurve c;
+
+      gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CLOSE,
+                                             (const graphene_point_t[]) { self->points[self->n_points - 1],
+                                                                          self->points[0] }));
+
+      winding += gsk_curve_get_crossing (&c, point);
+    }
+
+  return winding;
+}
+
 static GskPathFlags
 gsk_standard_contour_get_flags (const GskContour *contour)
 {
@@ -239,7 +289,7 @@ gsk_standard_contour_print (const GskContour *contour,
   const GskStandardContour *self = (const GskStandardContour *) contour;
   gsize i;
 
-  for (i = 0; i < self->n_ops; i ++)
+  for (i = 0; i < self->n_ops; i++)
     {
       const graphene_point_t *pt = gsk_pathop_points (self->ops[i]);
 
@@ -276,7 +326,7 @@ gsk_standard_contour_print (const GskContour *contour,
           break;
 
         default:
-          g_assert_not_reached();
+          g_assert_not_reached ();
           return;
       }
     }
@@ -367,36 +417,12 @@ gsk_standard_contour_get_start_end (const GskContour *contour,
     *end = self->points[self->n_points - 1];
 }
 
-static int
-gsk_standard_contour_get_winding (const GskContour       *contour,
-                                  const graphene_point_t *point)
+static gsize
+gsk_standard_contour_get_n_points (const GskContour *contour)
 {
   GskStandardContour *self = (GskStandardContour *) contour;
-  int winding = 0;
 
-  for (gsize i = 0; i < self->n_ops; i ++)
-    {
-      GskCurve c;
-
-      if (gsk_pathop_op (self->ops[i]) == GSK_PATH_MOVE)
-        continue;
-
-      gsk_curve_init (&c, self->ops[i]);
-      winding += gsk_curve_get_crossing (&c, point);
-    }
-
-  if ((self->flags & GSK_PATH_CLOSED) == 0)
-    {
-      GskCurve c;
-
-      gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CLOSE,
-                                             (const graphene_point_t[]) { self->points[self->n_points - 1],
-                                                                          self->points[0] }));
-
-      winding += gsk_curve_get_crossing (&c, point);
-    }
-
-  return winding;
+  return self->n_ops;
 }
 
 static gboolean
@@ -420,8 +446,8 @@ gsk_standard_contour_get_closest_point (const GskContour       *contour,
       if (dist <= threshold)
         {
           *out_dist = dist;
-          result->data.std.idx = 0;
-          result->data.std.t = 0;
+          result->idx = 0;
+          result->t = 0;
           return TRUE;
         }
 
@@ -437,7 +463,8 @@ gsk_standard_contour_get_closest_point (const GskContour       *contour,
         continue;
 
       gsk_curve_init (&c, self->ops[i]);
-      if (gsk_curve_get_closest_point (&c, point, threshold, &distance, &t))
+      if (gsk_curve_get_closest_point (&c, point, threshold, &distance, &t) &&
+          distance < threshold)
         {
           best_idx = i;
           best_t = t;
@@ -448,8 +475,8 @@ gsk_standard_contour_get_closest_point (const GskContour       *contour,
   if (best_idx != G_MAXUINT)
     {
       *out_dist = threshold;
-      result->data.std.idx = best_idx;
-      result->data.std.t = best_t;
+      result->idx = best_idx;
+      result->t = best_t;
       return TRUE;
     }
 
@@ -464,14 +491,14 @@ gsk_standard_contour_get_position (const GskContour *contour,
   GskStandardContour *self = (GskStandardContour *) contour;
   GskCurve curve;
 
-  if (G_UNLIKELY (point->data.std.idx == 0))
+  if (G_UNLIKELY (point->idx == 0))
     {
       *position = self->points[0];
       return;
     }
 
-  gsk_curve_init (&curve, self->ops[point->data.std.idx]);
-  gsk_curve_get_point (&curve, point->data.std.t, position);
+  gsk_curve_init (&curve, self->ops[point->idx]);
+  gsk_curve_get_point (&curve, point->t, position);
 }
 
 static void
@@ -485,19 +512,19 @@ gsk_standard_contour_get_tangent (const GskContour *contour,
   gsize idx;
   float t;
 
-  if (G_UNLIKELY (point->data.std.idx == 0))
+  if (G_UNLIKELY (point->idx == 0))
     {
       graphene_vec2_init (tangent, 1, 0);
       return;
     }
 
-  idx = point->data.std.idx;
-  t = point->data.std.t;
+  idx = point->idx;
+  t = point->t;
 
   if (t == 0 && direction == GSK_PATH_START)
     {
       /* Look at the previous segment */
-      if (idx > 0)
+      if (idx > 1)
         {
           idx--;
           t = 1;
@@ -518,7 +545,7 @@ gsk_standard_contour_get_tangent (const GskContour *contour,
         }
       else if (self->flags & GSK_PATH_CLOSED)
         {
-          idx = 0;
+          idx = 1;
           t = 0;
         }
     }
@@ -535,11 +562,310 @@ gsk_standard_contour_get_curvature (const GskContour *contour,
   GskStandardContour *self = (GskStandardContour *) contour;
   GskCurve curve;
 
-  if (G_UNLIKELY (point->data.std.idx == 0))
+  if (G_UNLIKELY (point->idx == 0))
     return 0;
 
-  gsk_curve_init (&curve, self->ops[point->data.std.idx]);
-  return gsk_curve_get_curvature (&curve, point->data.std.t, center);
+  gsk_curve_init (&curve, self->ops[point->idx]);
+  return gsk_curve_get_curvature (&curve, point->t, center);
+}
+
+static void
+add_curve (GskCurve       *curve,
+           GskPathBuilder *builder,
+           gboolean       *emit_move_to)
+{
+  if (*emit_move_to)
+    {
+      const graphene_point_t *s;
+
+      s = gsk_curve_get_start_point (curve);
+      gsk_path_builder_move_to (builder, s->x, s->y);
+      *emit_move_to = FALSE;
+    }
+  gsk_curve_builder_to (curve, builder);
+}
+
+static void
+gsk_standard_contour_add_segment (const GskContour *contour,
+                                  GskPathBuilder   *builder,
+                                  gboolean          emit_move_to,
+                                  GskRealPathPoint *start,
+                                  GskRealPathPoint *end)
+{
+  GskStandardContour *self = (GskStandardContour *) contour;
+  GskCurve c, c1, c2;
+
+  gsk_curve_init (&c, self->ops[start->idx]);
+
+  if (start->idx == end->idx)
+    {
+      gsk_curve_segment (&c, start->t, end->t, &c1);
+      add_curve (&c1, builder, &emit_move_to);
+      return;
+    }
+  if (start->t == 0)
+    {
+      add_curve (&c, builder, &emit_move_to);
+    }
+  else if (start->t < 1)
+    {
+      gsk_curve_split (&c, start->t, &c1, &c2);
+      add_curve (&c2, builder, &emit_move_to);
+    }
+
+  for (gsize i = start->idx + 1; i < end->idx; i++)
+    {
+      gsk_curve_init (&c, self->ops[i]);
+      add_curve (&c, builder, &emit_move_to);
+    }
+
+  gsk_curve_init (&c, self->ops[end->idx]);
+  if (c.op == GSK_PATH_CLOSE)
+    c.op = GSK_PATH_LINE;
+
+  if (end->t == 1)
+    {
+      add_curve (&c, builder, &emit_move_to);
+    }
+  else if (end->t > 0)
+    {
+      gsk_curve_split (&c, end->t, &c1, &c2);
+      add_curve (&c, builder, &emit_move_to);
+    }
+}
+
+typedef struct
+{
+  float t;
+  float length;
+} GskCurveLutEntry;
+
+typedef struct
+{
+  gsize op;
+  float length;
+#ifdef USE_LUT
+  GArray *lut;
+#endif
+} GskCurveMeasureData;
+
+typedef struct
+{
+  float tolerance;
+  GArray *measure_data;
+} GskStandardContourMeasureData;
+
+#ifdef USE_LUT
+static void
+clear_lut (gpointer data)
+{
+  GskCurveMeasureData *md = data;
+
+  g_clear_pointer (&md->lut, g_array_unref);
+}
+#endif
+
+static gpointer
+gsk_standard_contour_init_measure (const GskContour *contour,
+                                   float             tolerance,
+                                   float            *out_length)
+{
+  const GskStandardContour *self = (const GskStandardContour *) contour;
+  GskStandardContourMeasureData *cd;
+  GskCurveMeasureData md;
+
+  cd = g_new0 (GskStandardContourMeasureData, 1);
+
+  cd->tolerance = tolerance;
+  cd->measure_data = g_array_new (FALSE, FALSE, sizeof (GskCurveMeasureData));
+
+  *out_length = 0;
+
+  md.op = 0;
+  md.length = 0;
+
+#ifdef USE_LUT
+  g_array_set_clear_func (cd->measure_data, clear_lut);
+  md.lut = NULL;
+#endif
+
+  g_array_append_val (cd->measure_data, md);
+
+  for (gsize i = 1; i < self->n_ops; i ++)
+    {
+      GskCurve curve;
+
+      gsk_curve_init (&curve, self->ops[i]);
+
+      md.op = i;
+      md.length = gsk_curve_get_length (&curve);
+      *out_length += md.length;
+
+#ifdef USE_LUT
+      md.lut = g_array_new (FALSE, FALSE, sizeof (GskCurveLutEntry));
+
+      GskCurveLutEntry e;
+      gsize n;
+
+      if (curve.op == GSK_PATH_LINE ||
+          curve.op == GSK_PATH_CLOSE)
+        n = 0;
+      else
+        n = (int) ceilf (md.length / tolerance);
+
+      e.t = 0;
+      e.length = 0;
+
+      g_array_append_val (md.lut, e);
+
+      for (gsize j = 1; j < n; j++)
+        {
+          GskCurve curve1;
+          e.t = j / (float) n;
+          gsk_curve_split (&curve, e.t, &curve1, NULL);
+          e.length = gsk_curve_get_length (&curve1);
+          g_array_append_val (md.lut, e);
+        }
+
+      e.t = 1;
+      e.length = md.length;
+      g_array_append_val (md.lut, e);
+
+      g_array_append_val (cd->measure_data, md);
+#endif
+    }
+
+  return cd;
+}
+
+static void
+gsk_standard_contour_free_measure (const GskContour *contour,
+                                   gpointer          data)
+{
+  GskStandardContourMeasureData *cd = data;
+
+  g_array_unref (cd->measure_data);
+  g_free (cd);
+}
+
+static void
+gsk_standard_contour_get_point (const GskContour *contour,
+                                gpointer          measure_data,
+                                float             distance,
+                                GskRealPathPoint *result)
+{
+  const GskStandardContour *self = (const GskStandardContour *) contour;
+  GskStandardContourMeasureData *cd = measure_data;
+  unsigned int i;
+  GskCurveMeasureData *md;
+
+  for (i = 1; i < cd->measure_data->len; i++)
+    {
+      md = &g_array_index (cd->measure_data, GskCurveMeasureData, i);
+
+      if (distance < md->length)
+        break;
+
+      distance -= md->length;
+    }
+
+  if (i == self->n_ops)
+    {
+      result->idx = self->n_ops - 1;
+      result->t = 1;
+    }
+  else if (distance > 0)
+    {
+      result->idx = i;
+
+#ifndef USE_LUT
+      GskCurve curve;
+
+      gsk_curve_init (&curve, self->ops[i]);
+      result->t = gsk_curve_at_length (&curve, distance, cd->tolerance / 2);
+#else
+      GskCurveLutEntry *e0, *e1;
+
+      e1 = &g_array_index (md->lut, GskCurveLutEntry, 0);
+      for (gsize j = 1; j < md->lut->len; j++)
+        {
+          e0 = e1;
+          e1 = &g_array_index (md->lut, GskCurveLutEntry, j);
+
+          if (e1->length > distance)
+            {
+              float fraction = (e1->length - distance) / (e1->length - e0->length);
+              result->t = e0->t + fraction * (e1->t - e0->t);
+              break;
+            }
+        }
+#endif
+    }
+  else
+    {
+      result->idx = i;
+      result->t = 0;
+    }
+}
+
+static float
+gsk_standard_contour_get_distance (const GskContour *contour,
+                                   GskRealPathPoint *point,
+                                   gpointer          measure_data)
+{
+  const GskStandardContour *self = (const GskStandardContour *) contour;
+  GskStandardContourMeasureData *cd = measure_data;
+  float length;
+  GskCurveMeasureData *md;
+
+  if (G_UNLIKELY (point->idx == 0))
+    return 0;
+
+  length = 0;
+
+  for (gsize i = 1; i < self->n_ops; i++)
+    {
+      md = &g_array_index (cd->measure_data, GskCurveMeasureData, i);
+
+      if (i == point->idx)
+        break;
+
+      length += md->length;
+    }
+
+  if (point->t == 1)
+    {
+      length += md->length;
+    }
+  else if (point->t > 0)
+    {
+#ifndef USE_LUT
+      GskCurve curve, curve1;
+
+      gsk_curve_init (&curve, self->ops[md->op]);
+      gsk_curve_split (&curve, point->t, &curve1, NULL);
+
+      length += gsk_curve_get_length (&curve1);
+#else
+      GskCurveLutEntry *e0, *e1;
+
+      e1 = &g_array_index (md->lut, GskCurveLutEntry, 0);
+      for (gsize i = 1; i < md->lut->len; i++)
+        {
+          e0 = e1;
+          e1 = &g_array_index (md->lut, GskCurveLutEntry, i);
+
+          if (e1->t > point->t)
+            {
+              float fraction = (point->t - e0->t) / (e1->t - e0->t);
+              length += e0->length + fraction * (e1->length - e0->length);
+              break;
+            }
+        }
+#endif
+    }
+
+  return length;
 }
 
 static const GskContourClass GSK_STANDARD_CONTOUR_CLASS =
@@ -556,10 +882,16 @@ static const GskContourClass GSK_STANDARD_CONTOUR_CLASS =
   gsk_standard_contour_foreach,
   gsk_standard_contour_reverse,
   gsk_standard_contour_get_winding,
+  gsk_standard_contour_get_n_points,
   gsk_standard_contour_get_closest_point,
   gsk_standard_contour_get_position,
   gsk_standard_contour_get_tangent,
   gsk_standard_contour_get_curvature,
+  gsk_standard_contour_add_segment,
+  gsk_standard_contour_init_measure,
+  gsk_standard_contour_free_measure,
+  gsk_standard_contour_get_point,
+  gsk_standard_contour_get_distance,
 };
 
 /* You must ensure the contour has enough size allocated,
@@ -588,10 +920,8 @@ gsk_standard_contour_init (GskContour             *contour,
 
   offset += self->points - points;
   for (i = 0; i < n_ops; i++)
-    {
-      self->ops[i] = gsk_pathop_encode (gsk_pathop_op (ops[i]),
-                                        gsk_pathop_points (ops[i]) + offset);
-    }
+    self->ops[i] = gsk_pathop_encode (gsk_pathop_op (ops[i]),
+                                      gsk_pathop_points (ops[i]) + offset);
 }
 
 GskContour *
@@ -696,6 +1026,12 @@ gsk_contour_get_winding (const GskContour       *self,
   return self->klass->get_winding (self, point);
 }
 
+gsize
+gsk_contour_get_n_points (const GskContour *self)
+{
+  return self->klass->get_n_points (self);
+}
+
 gboolean
 gsk_contour_get_closest_point (const GskContour       *self,
                                const graphene_point_t *point,
@@ -731,6 +1067,48 @@ gsk_contour_get_curvature (const GskContour *self,
   return self->klass->get_curvature (self, point, center);
 }
 
+void
+gsk_contour_add_segment (const GskContour *self,
+                         GskPathBuilder   *builder,
+                         gboolean          emit_move_to,
+                         GskRealPathPoint *start,
+                         GskRealPathPoint *end)
+{
+  self->klass->add_segment (self, builder, emit_move_to, start, end);
+}
+
+gpointer
+gsk_contour_init_measure (const GskContour *self,
+                          float             tolerance,
+                          float            *out_length)
+{
+  return self->klass->init_measure (self, tolerance, out_length);
+}
+
+void
+gsk_contour_free_measure (const GskContour *self,
+                          gpointer          data)
+{
+  self->klass->free_measure (self, data);
+}
+
+void
+gsk_contour_get_point (const GskContour *self,
+                       gpointer          measure_data,
+                       float             offset,
+                       GskRealPathPoint *result)
+{
+  self->klass->get_point (self, measure_data, offset, result);
+}
+
+float
+gsk_contour_get_distance (const GskContour *self,
+                          GskRealPathPoint *point,
+                          gpointer          measure_data)
+{
+  return self->klass->get_distance (self, point, measure_data);
+}
+
 /* }}} */
 
 /* vim:set foldmethod=marker expandtab: */

gsk/gskcontourprivate.h

@@ -57,14 +57,17 @@ void                    gsk_contour_get_start_end               (const GskContou
                                                                  graphene_point_t       *end);
 int                     gsk_contour_get_winding                 (const GskContour       *self,
                                                                  const graphene_point_t *point);
+gsize                   gsk_contour_get_n_points                (const GskContour       *self);
 gboolean                gsk_contour_get_closest_point           (const GskContour       *self,
                                                                  const graphene_point_t *point,
                                                                  float                   threshold,
                                                                  GskRealPathPoint       *result,
                                                                  float                  *out_dist);
+
 void                    gsk_contour_get_position                (const GskContour       *self,
                                                                  GskRealPathPoint       *point,
                                                                  graphene_point_t       *pos);
+
 void                    gsk_contour_get_tangent                 (const GskContour       *self,
                                                                  GskRealPathPoint       *point,
                                                                  GskPathDirection        direction,
@@ -73,4 +76,24 @@ float                   gsk_contour_get_curvature               (const GskContou
                                                                  GskRealPathPoint       *point,
                                                                  graphene_point_t       *center);
 
+void                    gsk_contour_add_segment                 (const GskContour       *self,
+                                                                 GskPathBuilder         *builder,
+                                                                 gboolean                emit_move_to,
+                                                                 GskRealPathPoint       *start,
+                                                                 GskRealPathPoint       *end);
+
+
+gpointer                gsk_contour_init_measure                (const GskContour       *self,
+                                                                 float                   tolerance,
+                                                                 float                  *out_length);
+void                    gsk_contour_free_measure                (const GskContour       *self,
+                                                                 gpointer                data);
+void                    gsk_contour_get_point                   (const GskContour       *self,
+                                                                 gpointer                measure_data,
+                                                                 float                   offset,
+                                                                 GskRealPathPoint       *result);
+float                   gsk_contour_get_distance                (const GskContour       *self,
+                                                                 GskRealPathPoint       *point,
+                                                                 gpointer                measure_data);
+
 G_END_DECLS

gsk/gskcurve.c

@@ -24,7 +24,7 @@
 
 /* GskCurve collects all the functionality we need for Bézier segments */
 
-#define MIN_PROGRESS (1/1024.f)
+#define MIN_PROGRESS (1/2048.f)
 
 typedef struct _GskCurveClass GskCurveClass;
 
@@ -524,20 +524,6 @@ gsk_quad_curve_segment (const GskCurve *curve,
   gsk_quad_curve_split (&tmp, (end - start) / (1.0f - start), segment, NULL);
 }
 
-/* taken from Skia, including the very descriptive name */
-static gboolean
-gsk_quad_curve_too_curvy (const GskQuadCurve *self,
-                               float          tolerance)
-{
-  const graphene_point_t *pts = self->points;
-  float dx, dy;
-
-  dx = fabs (pts[1].x / 2 - (pts[0].x + pts[2].x) / 4);
-  dy = fabs (pts[1].y / 2 - (pts[0].y + pts[2].y) / 4);
-
-  return MAX (dx, dy) > tolerance;
-}
-
 static gboolean
 gsk_quad_curve_decompose_step (const GskCurve      *curve,
                                float                start_progress,
@@ -550,8 +536,8 @@ gsk_quad_curve_decompose_step (const GskCurve      *curve,
   GskCurve left, right;
   float mid_progress;
 
-  if (!gsk_quad_curve_too_curvy (self, tolerance))
-    return add_line_func (&self->points[0], &self->points[2], start_progress, end_progress, GSK_CURVE_LINE_REASON_STRAIGHT, user_data);
+  if (graphene_point_distance (&self->points[0], &self->points[2], NULL, NULL) < tolerance)
+    return add_line_func (&self->points[0], &self->points[2], start_progress, end_progress, GSK_CURVE_LINE_REASON_SHORT, user_data);
   if (end_progress - start_progress <= MIN_PROGRESS)
     return add_line_func (&self->points[0], &self->points[2], start_progress, end_progress, GSK_CURVE_LINE_REASON_SHORT, user_data);
 
@@ -994,25 +980,6 @@ gsk_cubic_curve_segment (const GskCurve *curve,
   gsk_cubic_curve_split (&tmp, (end - start) / (1.0f - start), segment, NULL);
 }
 
-/* taken from Skia, including the very descriptive name */
-static gboolean
-gsk_cubic_curve_too_curvy (const GskCubicCurve *self,
-                           float                tolerance)
-{
-  const graphene_point_t *pts = self->points;
-  graphene_point_t p;
-
-  graphene_point_interpolate (&pts[0], &pts[3], 1.0f / 3, &p);
-  if (MAX (ABS (p.x - pts[1].x), ABS (p.y - pts[1].y)) > tolerance)
-    return TRUE;
-
-  graphene_point_interpolate (&pts[0], &pts[3], 2.0f / 3, &p);
-  if (MAX (ABS (p.x - pts[2].x), ABS (p.y - pts[2].y)) > tolerance)
-    return TRUE;
-
-  return FALSE;
-}
-
 static gboolean
 gsk_cubic_curve_decompose_step (const GskCurve      *curve,
                                 float                start_progress,
@@ -1025,8 +992,8 @@ gsk_cubic_curve_decompose_step (const GskCurve      *curve,
   GskCurve left, right;
   float mid_progress;
 
-  if (!gsk_cubic_curve_too_curvy (self, tolerance))
-    return add_line_func (&self->points[0], &self->points[3], start_progress, end_progress, GSK_CURVE_LINE_REASON_STRAIGHT, user_data);
+  if (graphene_point_distance (&self->points[0], &self->points[3], NULL, NULL) < tolerance)
+    return add_line_func (&self->points[0], &self->points[3], start_progress, end_progress, GSK_CURVE_LINE_REASON_SHORT, user_data);
   if (end_progress - start_progress <= MIN_PROGRESS)
     return add_line_func (&self->points[0], &self->points[3], start_progress, end_progress, GSK_CURVE_LINE_REASON_SHORT, user_data);
 
@@ -1528,6 +1495,132 @@ gsk_curve_get_closest_point (const GskCurve         *curve,
     return find_closest_point (curve, point, threshold, 0, 1, out_dist, out_t);
 }
 
+/* Legendre-Gauss values for n=24,
+ * see https://pomax.github.io/bezierinfo/legendre-gauss.html
+ */
+
+const double T[] = {
+    -0.0640568928626056260850430826247450385909,
+    0.0640568928626056260850430826247450385909,
+    -0.1911188674736163091586398207570696318404,
+    0.1911188674736163091586398207570696318404,
+    -0.3150426796961633743867932913198102407864,
+    0.3150426796961633743867932913198102407864,
+    -0.4337935076260451384870842319133497124524,
+    0.4337935076260451384870842319133497124524,
+    -0.5454214713888395356583756172183723700107,
+    0.5454214713888395356583756172183723700107,
+    -0.6480936519369755692524957869107476266696,
+    0.6480936519369755692524957869107476266696,
+    -0.7401241915785543642438281030999784255232,
+    0.7401241915785543642438281030999784255232,
+    -0.8200019859739029219539498726697452080761,
+    0.8200019859739029219539498726697452080761,
+    -0.8864155270044010342131543419821967550873,
+    0.8864155270044010342131543419821967550873,
+    -0.9382745520027327585236490017087214496548,
+    0.9382745520027327585236490017087214496548,
+    -0.9747285559713094981983919930081690617411,
+    0.9747285559713094981983919930081690617411,
+    -0.9951872199970213601799974097007368118745,
+    0.9951872199970213601799974097007368118745,
+};
+
+const double C[] = {
+    0.1279381953467521569740561652246953718517,
+    0.1279381953467521569740561652246953718517,
+    0.1258374563468282961213753825111836887264,
+    0.1258374563468282961213753825111836887264,
+    0.121670472927803391204463153476262425607,
+    0.121670472927803391204463153476262425607,
+    0.1155056680537256013533444839067835598622,
+    0.1155056680537256013533444839067835598622,
+    0.1074442701159656347825773424466062227946,
+    0.1074442701159656347825773424466062227946,
+    0.0976186521041138882698806644642471544279,
+    0.0976186521041138882698806644642471544279,
+    0.086190161531953275917185202983742667185,
+    0.086190161531953275917185202983742667185,
+    0.0733464814110803057340336152531165181193,
+    0.0733464814110803057340336152531165181193,
+    0.0592985849154367807463677585001085845412,
+    0.0592985849154367807463677585001085845412,
+    0.0442774388174198061686027482113382288593,
+    0.0442774388174198061686027482113382288593,
+    0.0285313886289336631813078159518782864491,
+    0.0285313886289336631813078159518782864491,
+    0.0123412297999871995468056670700372915759,
+    0.0123412297999871995468056670700372915759,
+};
+
+/* Compute arclength by using Gauss quadrature on
+ *
+ * \int_0^z \sqrt{ (dx/dt)^2 + (dy/dt)^2 } dt
+ */
+float
+gsk_curve_get_length (const GskCurve *curve)
+{
+  double z = 0.5;
+  double sum;
+  GskCurve derivative;
+  graphene_point_t d;
+
+  if (curve->op == GSK_PATH_LINE ||
+      curve->op == GSK_PATH_CLOSE)
+    return graphene_point_distance (gsk_curve_get_start_point (curve),
+                                    gsk_curve_get_end_point (curve),
+                                    NULL, NULL);
+
+  gsk_curve_get_derivative (curve, &derivative);
+
+  sum = 0;
+
+  for (unsigned int i = 0; i < G_N_ELEMENTS (T); i++)
+    {
+      double t = z * T[i] + z;
+      gsk_curve_get_point (&derivative, t, &d);
+      sum += C[i] * sqrt (d.x * d.x + d.y * d.y);
+    }
+
+  return z * sum;
+}
+
+/* Compute the inverse of the arclength using bisection,
+ * to a given precision
+ */
+float
+gsk_curve_at_length (const GskCurve *curve,
+                     float           length,
+                     float           epsilon)
+{
+  float t1, t2, t, l;
+  GskCurve c1;
+  //int loop_count = 0;
+
+  t1 = 0;
+  t2 = 1;
+
+  while (t1 < t2)
+    {
+      //loop_count++;
+      t = (t1 + t2) / 2;
+
+      gsk_curve_split (curve, t, &c1, NULL);
+
+      l = gsk_curve_get_length (&c1);
+      if (fabs (length - l) < epsilon)
+        break;
+      else if (l < length)
+        t1 = t;
+      else
+        t2 = t;
+    }
+
+  //g_print ("loop count %d\n", loop_count);
+
+  return t;
+}
+
 /* }}} */
 
 /* vim:set foldmethod=marker expandtab: */

gsk/gskcurveprivate.h

@@ -153,5 +153,10 @@ gboolean                gsk_curve_get_closest_point             (const GskCurve
                                                                  float                  *out_dist,
                                                                  float                  *out_t);
 
+float                  gsk_curve_get_length                     (const GskCurve         *curve);
+float                  gsk_curve_at_length                      (const GskCurve         *curve,
+                                                                 float                   distance,
+                                                                 float                   epsilon);
+
 G_END_DECLS
 

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
@@ -42,8 +42,6 @@
  * @GSK_REPEAT_NODE: A node that repeats the child's contents
  * @GSK_CLIP_NODE: A node that clips its child to a rectangular area
  * @GSK_ROUNDED_CLIP_NODE: A node that clips its child to a rounded rectangle
- * @GSK_FILL_NODE: A node that fills a path
- * @GSK_STROKE_NODE: A node that strokes a path
  * @GSK_SHADOW_NODE: A node that draws a shadow below its child
  * @GSK_BLEND_NODE: A node that blends two children together
  * @GSK_CROSS_FADE_NODE: A node that cross-fades between two children
@@ -53,7 +51,9 @@
  * @GSK_GL_SHADER_NODE: A node that uses OpenGL fragment shaders to render
  * @GSK_TEXTURE_SCALE_NODE: A node drawing a `GdkTexture` scaled and filtered (Since: 4.10)
  * @GSK_MASK_NODE: A node that masks one child with another (Since: 4.10)
- 
+ * @GSK_FILL_NODE: A node that fills a path
+ * @GSK_STROKE_NODE: A node that strokes a path
+
  * The type of a node determines what the node is rendering.
  */
 typedef enum {
@@ -76,8 +76,6 @@ 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,
@@ -86,7 +84,9 @@ typedef enum {
   GSK_DEBUG_NODE,
   GSK_GL_SHADER_NODE,
   GSK_TEXTURE_SCALE_NODE,
-  GSK_MASK_NODE
+  GSK_MASK_NODE,
+  GSK_FILL_NODE,
+  GSK_STROKE_NODE
 } GskRenderNodeType;
 
 /**

gsk/gskpath.c

@@ -42,6 +42,8 @@
  * Conceptually, a path consists of zero or more contours (continous, connected
  * curves), each of which may or may not be closed. Contours are typically
  * constructed from Bézier segments.
+ *
+ * Since: 4.14
  */
 
 struct _GskPath
@@ -420,6 +422,7 @@ gsk_path_get_bounds (GskPath         *self,
  *
  * Returns: `TRUE` if the path has bounds, `FALSE` if the path is known
  *   to be empty and have no bounds.
+ * Since: 4.14
  */
 gboolean
 gsk_path_get_stroke_bounds (GskPath         *self,
@@ -490,6 +493,72 @@ gsk_path_in_fill (GskPath                *self,
     }
 }
 
+/**
+ * gsk_path_get_start_point:
+ * @self: a `GskPath`
+ * @result: (out caller-allocates): return location for point
+ *
+ * Gets the start point of the path.
+ *
+ * An empty path has no points, so `FALSE`
+ * is returned in this case.
+ *
+ * Returns: `TRUE` if @result was filled
+ *
+ * Since: 4.14
+ */
+gboolean
+gsk_path_get_start_point (GskPath      *self,
+                          GskPathPoint *result)
+{
+  GskRealPathPoint *res = (GskRealPathPoint *) result;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (result != NULL, FALSE);
+
+  if (self->n_contours == 0)
+    return FALSE;
+
+  res->contour = 0;
+  res->idx = 1;
+  res->t = 0;
+
+  return TRUE;
+}
+
+/**
+ * gsk_path_get_end_point:
+ * @self: a `GskPath`
+ * @result: (out caller-allocates): return location for point
+ *
+ * Gets the end point of the path.
+ *
+ * An empty path has no points, so `FALSE`
+ * is returned in this case.
+ *
+ * Returns: `TRUE` if @result was filled
+ *
+ * Since: 4.14
+ */
+gboolean
+gsk_path_get_end_point (GskPath      *self,
+                        GskPathPoint *result)
+{
+  GskRealPathPoint *res = (GskRealPathPoint *) result;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (result != NULL, FALSE);
+
+  if (self->n_contours == 0)
+    return FALSE;
+
+  res->contour = self->n_contours - 1;
+  res->idx = gsk_contour_get_n_points (self->contours[self->n_contours - 1]) - 1;
+  res->t = 1;
+
+  return TRUE;
+}
+
 /**
  * gsk_path_get_closest_point:
  * @self: a `GskPath`
@@ -532,7 +601,6 @@ gsk_path_get_closest_point (GskPath                *self,
         {
           found = TRUE;
           res->contour = i;
-          res->path = self;
           threshold = distance;
         }
     }

gsk/gskpath.h

@@ -41,6 +41,8 @@ G_BEGIN_DECLS
  * 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`.
+ *
+ * Since: 4.14
  */
 typedef enum
 {
@@ -110,6 +112,13 @@ gboolean                gsk_path_in_fill                        (GskPath
                                                                  const graphene_point_t *point,
                                                                  GskFillRule             fill_rule);
 
+GDK_AVAILABLE_IN_4_14
+gboolean                gsk_path_get_start_point                (GskPath                *self,
+                                                                 GskPathPoint           *result);
+GDK_AVAILABLE_IN_4_14
+gboolean                gsk_path_get_end_point                  (GskPath                *self,
+                                                                 GskPathPoint           *result);
+
 GDK_AVAILABLE_IN_4_14
 gboolean                gsk_path_get_closest_point              (GskPath                *self,
                                                                  const graphene_point_t *point,

gsk/gskpathbuilder.c

@@ -63,6 +63,8 @@
  * back with a line to the starting point.
  *
  * This is similar for how paths are drawn in Cairo.
+ *
+ * Since: 4.14
  */
 
 struct _GskPathBuilder
@@ -983,3 +985,77 @@ gsk_path_builder_add_layout (GskPathBuilder *self,
   cairo_destroy (cr);
   cairo_surface_destroy (surface);
 }
+
+/**
+ * gsk_path_builder_add_segment:
+ * @self: a `GskPathBuilder`
+ * @path: the `GskPath` to take the segment to
+ * @start: the point on @path to start at
+ * @end: the point on @path to end at
+ *
+ * Adds to @self the segment of @path from @start to @end.
+ *
+ * If @start is equal to or after @end, 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.
+ *
+ * Note that this method always adds a path with the given start point
+ * and end point. To add a closed path, use [method@Gsk.PathBuilder.add_path].
+ *
+ * Since: 4.14
+ */
+void
+gsk_path_builder_add_segment (GskPathBuilder     *self,
+                              GskPath            *path,
+                              const GskPathPoint *start,
+                              const GskPathPoint *end)
+{
+  GskRealPathPoint *s = (GskRealPathPoint *) start;
+  GskRealPathPoint *e = (GskRealPathPoint *) end;
+  const GskContour *contour;
+  gsize n_contours = gsk_path_get_n_contours (path);
+
+  g_return_if_fail (self != NULL);
+  g_return_if_fail (path != NULL);
+  g_return_if_fail (start != NULL);
+  g_return_if_fail (end != NULL);
+  g_return_if_fail (s->contour < n_contours);
+  g_return_if_fail (e->contour < n_contours);
+
+  contour = gsk_path_get_contour (path, s->contour);
+
+  if (s->contour == e->contour)
+    {
+      if (gsk_path_point_compare (start, end) < 0)
+        {
+          gsk_contour_add_segment (contour, self, TRUE, s, e);
+          goto out;
+        }
+      else if (n_contours == 1)
+        {
+          gsk_contour_add_segment (contour, self, TRUE,
+                                   s,
+                                   &(GskRealPathPoint) { s->contour, gsk_contour_get_n_points (contour) - 1, 1 });
+          gsk_contour_add_segment (contour, self, FALSE,
+                                   &(GskRealPathPoint) { s->contour, 1, 0 },
+                                   e);
+          goto out;
+        }
+    }
+
+  gsk_contour_add_segment (contour, self, TRUE,
+                           s,
+                           &(GskRealPathPoint) { s->contour, gsk_contour_get_n_points (contour) - 1, 1 });
+
+  for (gsize i = (s->contour + 1) % n_contours; i != e->contour; i = (i + 1) % n_contours)
+    gsk_path_builder_add_contour (self, gsk_contour_dup (gsk_path_get_contour (path, i)));
+
+  contour = gsk_path_get_contour (path, e->contour);
+  gsk_contour_add_segment (contour, self, FALSE,
+                           &(GskRealPathPoint) { e->contour, 1, 0 },
+                           e);
+
+out:
+  gsk_path_builder_end_current (self);
+}

gsk/gskpathbuilder.h

@@ -68,6 +68,11 @@ GDK_AVAILABLE_IN_4_14
 void                    gsk_path_builder_add_circle             (GskPathBuilder         *self,
                                                                  const graphene_point_t *center,
                                                                  float                   radius);
+GDK_AVAILABLE_IN_4_14
+void                    gsk_path_builder_add_segment            (GskPathBuilder         *self,
+                                                                 GskPath                *path,
+                                                                 const GskPathPoint     *start,
+                                                                 const GskPathPoint     *end);
 
 GDK_AVAILABLE_IN_4_14
 void                    gsk_path_builder_move_to                (GskPathBuilder         *self,

gsk/gskpathmeasure.c

@@ -0,0 +1,328 @@
+/*
+ * 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 "gskpathpointprivate.h"
+#include "gskpathprivate.h"
+
+/**
+ * GskPathMeasure:
+ *
+ * `GskPathMeasure` is an object that allows measurements
+ * on `GskPath`s such as determining the length of the path.
+ *
+ * Many measuring operations require approximating the path
+ * with simpler shapes. Therefore, a `GskPathMeasure` has
+ * a tolerance that determines what precision is required
+ * for such approximations.
+ *
+ * A `GskPathMeasure` struct is a reference counted struct
+ * and should be treated as opaque.
+ */
+
+typedef struct _GskContourMeasure GskContourMeasure;
+
+struct _GskContourMeasure
+{
+  float length;
+  gpointer contour_data;
+};
+
+struct _GskPathMeasure
+{
+  /*< private >*/
+  guint ref_count;
+
+  GskPath *path;
+  float tolerance;
+
+  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.
+ *
+ * Returns: a new `GskPathMeasure` representing @path
+ *
+ * Since: 4.14
+ */
+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
+ *
+ * Since: 4.14
+ */
+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;
+
+  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`.
+ *
+ * Since: 4.14
+ */
+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.
+ *
+ * Since: 4.14
+ */
+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
+ *
+ * Since: 4.14
+ */
+GskPath *
+gsk_path_measure_get_path (GskPathMeasure *self)
+{
+  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
+ *
+ * Since: 4.14
+ */
+float
+gsk_path_measure_get_tolerance (GskPathMeasure *self)
+{
+  return self->tolerance;
+}
+
+/**
+ * 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
+ *
+ * Since: 4.14
+ */
+float
+gsk_path_measure_get_length (GskPathMeasure *self)
+{
+  g_return_val_if_fail (self != NULL, 0);
+
+  return self->length;
+}
+
+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: the distance
+ * @result: (out caller-allocates): return location for the result
+ *
+ * Sets @result to the point at the given distance into the path.
+ *
+ * An empty path has no points, so `FALSE` is returned in that case.
+ *
+ * Returns: `TRUE` if @result was set
+ *
+ * Since: 4.14
+ */
+gboolean
+gsk_path_measure_get_point (GskPathMeasure *self,
+                            float           distance,
+                            GskPathPoint   *result)
+{
+  GskRealPathPoint *res = (GskRealPathPoint *) result;
+  gsize i;
+  float offset;
+  const GskContour *contour;
+
+  g_return_val_if_fail (self != NULL, FALSE);
+  g_return_val_if_fail (result != NULL, FALSE);
+
+  if (self->n_contours == 0)
+    return FALSE;
+
+  offset = gsk_path_measure_clamp_distance (self, distance);
+
+  for (i = 0; i < self->n_contours - 1; i++)
+    {
+      if (offset < self->measures[i].length)
+        break;
+
+      offset -= self->measures[i].length;
+    }
+
+  g_assert (0 <= i && i < self->n_contours);
+
+  offset = CLAMP (offset, 0, self->measures[i].length);
+
+  contour = gsk_path_get_contour (self->path, i);
+
+  gsk_contour_get_point (contour, self->measures[i].contour_data, offset, res);
+  res->contour = i;
+
+  return TRUE;
+}
+
+/**
+ * gsk_path_point_get_distance:
+ * @measure: a `GskPathMeasure`
+ * @point: a `GskPathPoint on the path of @self
+ *
+ * Returns the distance from the beginning of the path
+ * to @point.
+ *
+ * Returns: the distance of @point
+ *
+ * Since: 4.14
+ */
+float
+gsk_path_point_get_distance (GskPathMeasure     *measure,
+                             const GskPathPoint *point)
+{
+  GskRealPathPoint *p = (GskRealPathPoint *)point;
+  const GskContour *contour;
+  float contour_offset = 0;
+
+  g_return_val_if_fail (measure != NULL, 0);
+  g_return_val_if_fail (point != NULL, 0);
+  g_return_val_if_fail (p->contour < measure->n_contours, 0);
+
+  contour = gsk_path_get_contour (measure->path, p->contour);
+
+  for (gsize i = 0; i < measure->n_contours; i++)
+    {
+      if (contour == gsk_path_get_contour (measure->path, i))
+        return contour_offset + gsk_contour_get_distance (contour,
+                                                          p,
+                                                          measure->measures[i].contour_data);
+
+      contour_offset += measure->measures[i].length;
+    }
+
+  g_return_val_if_reached (0);
+}

gsk/gskpathmeasure.h

@@ -0,0 +1,62 @@
+/*
+ * 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>
+ */
+
+#pragma once
+
+#if !defined (__GSK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gsk/gsk.h> can be included directly."
+#endif
+
+
+#include <gsk/gskpath.h>
+#include <gsk/gskpathpoint.h>
+
+G_BEGIN_DECLS
+
+#define GSK_TYPE_PATH_MEASURE (gsk_path_measure_get_type ())
+
+GDK_AVAILABLE_IN_4_14
+GType                   gsk_path_measure_get_type               (void) G_GNUC_CONST;
+GDK_AVAILABLE_IN_4_14
+GskPathMeasure *        gsk_path_measure_new                    (GskPath                *path);
+GDK_AVAILABLE_IN_4_14
+GskPathMeasure *        gsk_path_measure_new_with_tolerance     (GskPath                *path,
+                                                                 float                   tolerance);
+
+GDK_AVAILABLE_IN_4_14
+GskPathMeasure *        gsk_path_measure_ref                    (GskPathMeasure         *self);
+GDK_AVAILABLE_IN_4_14
+void                    gsk_path_measure_unref                  (GskPathMeasure         *self);
+
+GDK_AVAILABLE_IN_4_14
+GskPath *               gsk_path_measure_get_path               (GskPathMeasure         *self) G_GNUC_PURE;
+GDK_AVAILABLE_IN_4_14
+float                   gsk_path_measure_get_tolerance          (GskPathMeasure         *self) G_GNUC_PURE;
+
+GDK_AVAILABLE_IN_4_14
+float                   gsk_path_measure_get_length             (GskPathMeasure         *self);
+
+GDK_AVAILABLE_IN_4_14
+gboolean                gsk_path_measure_get_point              (GskPathMeasure         *self,
+                                                                 float                   distance,
+                                                                 GskPathPoint           *result);
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskPathMeasure, gsk_path_measure_unref)
+
+G_END_DECLS

gsk/gskpathpoint.c

@@ -22,6 +22,7 @@
 #include "gskpathpointprivate.h"
 
 #include "gskcontourprivate.h"
+#include "gskpathmeasure.h"
 
 #include "gdk/gdkprivate.h"
 
@@ -33,12 +34,15 @@
  * It can be queried for properties of the path at that point, such as its
  * tangent or its curvature.
  *
- * To obtain a `GskPathPoint`, use [method@Gsk.Path.get_closest_point].
+ * To obtain a `GskPathPoint`, use [method@Gsk.Path.get_closest_point]
+ * or [method@Gsk.PathMeasure.get_point].
  *
  * Note that `GskPathPoint` structs are meant to be stack-allocated, and
  * don't a reference to the path object they are obtained from. It is the
  * callers responsibility to keep a reference to the path as long as the
  * `GskPathPoint` is used.
+ *
+ * Since: 4.14
  */
 
 G_DEFINE_BOXED_TYPE (GskPathPoint, gsk_path_point,
@@ -64,6 +68,77 @@ gsk_path_point_free (GskPathPoint *point)
   g_free (point);
 }
 
+/**
+ * gsk_path_point_equal:
+ * @point1: a `GskPathPoint`
+ * @point2: another `GskPathPoint`
+ *
+ * Returns whether the two path points refer to the same
+ * location on all paths.
+ *
+ * Note that the start- and endpoint of a closed contour
+ * will compare nonequal according to this definition.
+ * Use [method@Gsk.Path.is_closed] to find out if the
+ * start- and endpoint of a concrete path refer to the
+ * same location.
+ *
+ * Return: `TRUE` if @point1 and @point2 are equal
+ */
+gboolean
+gsk_path_point_equal (const GskPathPoint *point1,
+                      const GskPathPoint *point2)
+{
+  const GskRealPathPoint *p1 = (const GskRealPathPoint *) point1;
+  const GskRealPathPoint *p2 = (const GskRealPathPoint *) point2;
+
+  if (p1->contour == p2->contour)
+    {
+      if ((p1->idx     == p2->idx     && p1->t == p2->t) ||
+          (p1->idx + 1 == p2->idx     && p1->t == 1 && p2->t == 0) ||
+          (p1->idx     == p2->idx + 1 && p1->t == 0 && p2->t == 1))
+        return TRUE;
+    }
+
+  return FALSE;
+}
+
+/**
+ * gsk_path_point_compare:
+ * @point1: a `GskPathPoint`
+ * @point2: another `GskPathPoint`
+ *
+ * Returns whether @point1 is before or after @point2.
+ *
+ * Returns: -1 if @point1 is before @point2,
+ *   1 if @point1 is after @point2,
+ *   0 if they are equal
+ */
+int
+gsk_path_point_compare (const GskPathPoint *point1,
+                        const GskPathPoint *point2)
+{
+  const GskRealPathPoint *p1 = (const GskRealPathPoint *) point1;
+  const GskRealPathPoint *p2 = (const GskRealPathPoint *) point2;
+
+  if (gsk_path_point_equal (point1, point2))
+    return 0;
+
+  if (p1->contour < p2->contour)
+    return -1;
+  else if (p1->contour > p2->contour)
+    return 1;
+  else if (p1->idx < p2->idx)
+    return -1;
+  else if (p1->idx > p2->idx)
+    return 1;
+  else if (p1->t < p2->t)
+    return -1;
+  else if (p1->t > p2->t)
+    return 1;
+
+  return 0;
+}
+
 /**
  * gsk_path_point_get_position:
  * @path: a `GskPath`
@@ -81,11 +156,14 @@ gsk_path_point_get_position (GskPath            *path,
                              graphene_point_t   *position)
 {
   GskRealPathPoint *self = (GskRealPathPoint *) point;
-  const GskContour *contour = gsk_path_get_contour (path, self->contour);
+  const GskContour *contour;
 
-  g_return_if_fail (path == self->path);
-  g_return_if_fail (contour != NULL);
+  g_return_if_fail (path != NULL);
+  g_return_if_fail (point != NULL);
+  g_return_if_fail (position != NULL);
+  g_return_if_fail (self->contour < gsk_path_get_n_contours (path));
 
+  contour = gsk_path_get_contour (path, self->contour),
   gsk_contour_get_position (contour, self, position);
 }
 
@@ -114,11 +192,14 @@ gsk_path_point_get_tangent (GskPath            *path,
                             graphene_vec2_t    *tangent)
 {
   GskRealPathPoint *self = (GskRealPathPoint *) point;
-  const GskContour *contour = gsk_path_get_contour (path, self->contour);
+  const GskContour *contour;
 
-  g_return_if_fail (path == self->path);
-  g_return_if_fail (contour != NULL);
+  g_return_if_fail (path != NULL);
+  g_return_if_fail (point != NULL);
+  g_return_if_fail (tangent != NULL);
+  g_return_if_fail (self->contour < gsk_path_get_n_contours (path));
 
+  contour = gsk_path_get_contour (path, self->contour),
   gsk_contour_get_tangent (contour, self, direction, tangent);
 }
 
@@ -126,7 +207,7 @@ gsk_path_point_get_tangent (GskPath            *path,
  * gsk_path_point_get_curvature:
  * @path: a `GskPath`
  * @point: a `GskPathPoint` on @path
- * @center: (out caller-allocates): Return location for
+ * @center: (out caller-allocates) (nullable): Return location for
  *   the center of the osculating circle
  *
  * Calculates the curvature of the path at the point.
@@ -146,10 +227,12 @@ gsk_path_point_get_curvature (GskPath            *path,
                               graphene_point_t   *center)
 {
   GskRealPathPoint *self = (GskRealPathPoint *) point;
-  const GskContour *contour = gsk_path_get_contour (path, self->contour);
+  const GskContour *contour;
 
-  g_return_val_if_fail (path == self->path, 0);
-  g_return_val_if_fail (contour != NULL, 0);
+  g_return_val_if_fail (path != NULL, 0);
+  g_return_val_if_fail (point != NULL, 0);
+  g_return_val_if_fail (self->contour < gsk_path_get_n_contours (path), 0);
 
+  contour = gsk_path_get_contour (path, self->contour);
   return gsk_contour_get_curvature (contour, self, center);
 }

gsk/gskpathpoint.h

@@ -48,6 +48,14 @@ GskPathPoint *          gsk_path_point_copy            (GskPathPoint       *poin
 GDK_AVAILABLE_IN_4_14
 void                    gsk_path_point_free            (GskPathPoint       *point);
 
+GDK_AVAILABLE_IN_4_14
+gboolean                gsk_path_point_equal           (const GskPathPoint *point1,
+                                                        const GskPathPoint *point2);
+
+GDK_AVAILABLE_IN_4_14
+int                     gsk_path_point_compare         (const GskPathPoint *point1,
+                                                        const GskPathPoint *point2);
+
 GDK_AVAILABLE_IN_4_14
 void                    gsk_path_point_get_position    (GskPath            *path,
                                                         const GskPathPoint *point,
@@ -64,4 +72,8 @@ float                   gsk_path_point_get_curvature   (GskPath            *path
                                                         const GskPathPoint *point,
                                                         graphene_point_t   *center);
 
+GDK_AVAILABLE_IN_4_14
+float                   gsk_path_point_get_distance    (GskPathMeasure     *measure,
+                                                        const GskPathPoint *point);
+
 G_END_DECLS

gsk/gskpathpointprivate.h

@@ -7,15 +7,9 @@ G_BEGIN_DECLS
 
 struct _GskRealPathPoint
 {
-  GskPath *path;
   gsize contour;
-
-  union {
-    struct {
-      unsigned int idx;
-      float t;
-    } std;
-  } data;
+  gsize idx;
+  float t;
 };
 
 G_STATIC_ASSERT (sizeof (GskRealPathPoint) <= sizeof (GskPathPoint));

gsk/gskrendernodeimpl.c

@@ -3970,7 +3970,7 @@ gsk_repeat_node_draw (GskRenderNode *node,
   scale_x *= width / self->child_bounds.size.width;
   scale_y *= height / self->child_bounds.size.height;
   cairo_surface_set_device_scale (surface, scale_x, scale_y);
-  cairo_surface_set_device_offset (surface, 
+  cairo_surface_set_device_offset (surface,
                                    - self->child_bounds.origin.x * scale_x,
                                    - self->child_bounds.origin.y * scale_y);
 
@@ -4141,7 +4141,7 @@ gsk_clip_node_diff (GskRenderNode  *node1,
       gsk_render_node_diff_impossible (node1, node2, region);
     }
 }
- 
+
 static void
 gsk_clip_node_class_init (gpointer g_class,
                                gpointer class_data)
@@ -4372,6 +4372,15 @@ gsk_rounded_clip_node_get_clip (const GskRenderNode *node)
 /* }}} */
 /* {{{ GSK_FILL_NODE */
 
+/**
+ * GskFillNode:
+ *
+ * A render node filling the child node in the area given by [struct@Gsk.Path]
+ * and [enum@Gsk.FillRule].
+ *
+ * Since: 4.14
+ */
+
 struct _GskFillNode
 {
   GskRenderNode render_node;
@@ -4572,6 +4581,15 @@ gsk_fill_node_get_fill_rule (const GskRenderNode *node)
 /* }}} */
 /* {{{ GSK_STROKE_NODE */
 
+/**
+ * GskStrokeNode:
+ *
+ * A render node that will stroke the child node along the given [struct@Gsk.Path]
+ * using the [struct@Gsk.Stroke] attributes.
+ *
+ * Since: 4.14
+ */
+
 struct _GskStrokeNode
 {
   GskRenderNode render_node;

gsk/gskrendernodeprivate.h

@@ -14,7 +14,7 @@ typedef struct _GskRenderNodeClass GskRenderNodeClass;
  * We don't add an "n-types" value to avoid having to handle
  * it in every single switch.
  */
-#define GSK_RENDER_NODE_TYPE_N_TYPES    (GSK_MASK_NODE + 1)
+#define GSK_RENDER_NODE_TYPE_N_TYPES    (GSK_STROKE_NODE + 1)
 
 extern GType gsk_render_node_types[];
 

gsk/gskstroke.c

@@ -26,6 +26,8 @@
  *
  * A `GskStroke` struct collects the parameters that influence
  * the operation of stroking a path.
+ *
+ * Since: 4.14
  */
 
 G_DEFINE_BOXED_TYPE (GskStroke, gsk_stroke, gsk_stroke_copy, gsk_stroke_free)

gsk/gsktypes.h

@@ -27,6 +27,7 @@
 
 typedef struct _GskPath                 GskPath;
 typedef struct _GskPathBuilder          GskPathBuilder;
+typedef struct _GskPathMeasure          GskPathMeasure;
 typedef struct _GskPathPoint            GskPathPoint;
 typedef struct _GskRenderer             GskRenderer;
 typedef struct _GskStroke               GskStroke;

gsk/meson.build

@@ -28,6 +28,7 @@ gsk_public_sources = files([
   'gskglshader.c',
   'gskpath.c',
   'gskpathbuilder.c',
+  'gskpathmeasure.c',
   'gskpathpoint.c',
   'gskrenderer.c',
   'gskrendernode.c',
@@ -75,6 +76,7 @@ gsk_public_headers = files([
   'gskglshader.h',
   'gskpath.h',
   'gskpathbuilder.h',
+  'gskpathmeasure.h',
   'gskpathpoint.h',
   'gskrenderer.h',
   'gskrendernode.h',

gtk/gtklistheader.c

@@ -27,9 +27,9 @@
  * `GtkListHeader` is used by list widgets to represent the headers they
  * display.
  *
- * The `GtkListHeader`s are managed just like [class@gtk.ListItem]s via
- * their factory, but provide a different set of properties suitable for
- * managing the header instead of individual items.
+ * `GtkListHeader` objects are managed just like [class@Gtk.ListItem]
+ * objects via their factory, but provide a different set of properties suitable
+ * for managing the header instead of individual items.
  *
  * Since: 4.12
  */

gtk/gtklistitem.c

@@ -27,13 +27,14 @@
 /**
  * GtkListItem:
  *
- * `GtkListItem` is used by list widgets to represent items in a `GListModel`.
+ * `GtkListItem` is used by list widgets to represent items in a
+ * [iface@Gio.ListModel].
  *
- * The `GtkListItem`s are managed by the list widget (with its factory)
+ * `GtkListItem` objects are managed by the list widget (with its factory)
  * and cannot be created by applications, but they need to be populated
  * by application code. This is done by calling [method@Gtk.ListItem.set_child].
  *
- * `GtkListItem`s exist in 2 stages:
+ * `GtkListItem` objects exist in 2 stages:
  *
  * 1. The unbound stage where the listitem is not currently connected to
  *    an item in the list. In that case, the [property@Gtk.ListItem:item]

gtk/gtkoverlaylayout.c

@@ -33,12 +33,12 @@
 /**
  * GtkOverlayLayout:
  *
- * `GtkOverlayLayout` is the layout manager used by `GtkOverlay`.
+ * `GtkOverlayLayout` is the layout manager used by [class@Gtk.Overlay].
  *
  * It places widgets as overlays on top of the main child.
  *
  * This is not a reusable layout manager, since it expects its widget
- * to be a `GtkOverlay`. It only listed here so that its layout
+ * to be a `GtkOverlay`. It is only listed here so that its layout
  * properties get documented.
  */
 

modules/printbackends/gtkprintbackendcpdb.h

@@ -23,7 +23,7 @@
 
 #include <glib-object.h>
 #include <gtk/gtk.h>
-#include "gtkprintbackendprivate.h"
+#include "gtk/print/gtkprintbackendprivate.h"
 
 G_BEGIN_DECLS
 

modules/printbackends/gtkprintercpdb.h

@@ -21,7 +21,7 @@
 
 #include <glib-object.h>
 #include <cpdb/cpdb-frontend.h>
-#include <gtk/gtkprinterprivate.h>
+#include <gtk/print/gtkprinterprivate.h>
 
 G_BEGIN_DECLS
 
@@ -43,4 +43,4 @@ void                  gtk_printer_cpdb_set_printer_obj        (GtkPrinterCpdb
 
 G_END_DECLS
 
-#endif /* __GTK_PRINTER_CPDB_H__ */
+#endif /* __GTK_PRINTER_CPDB_H__ */

testsuite/gsk/curve-special-cases.c

@@ -145,6 +145,28 @@ test_curve_crossing (void)
     }
 }
 
+static void
+test_bad_split (void)
+{
+  GskCurve c, c1, c2;
+  float t[2], l, l1, l2;
+
+  parse_curve (&c, "M 0 0 C 2 0 4 0 4 0");
+
+  l = gsk_curve_get_length (&c);
+
+  t[0] = 0.5;
+  t[1] = gsk_curve_at_length (&c, 2, FLT_EPSILON);
+
+  for (unsigned int i = 0; i < G_N_ELEMENTS (t); i++)
+    {
+      gsk_curve_split (&c, t[i], &c1, &c2);
+      l1 = gsk_curve_get_length (&c1);
+      l2 = gsk_curve_get_length (&c2);
+      g_print ("split at t=%g: %g == %g + %g, error %f\n", t[i], l, l1, l2, l - (l1 + l2));
+    }
+}
+
 int
 main (int   argc,
       char *argv[])
@@ -154,6 +176,7 @@ main (int   argc,
   g_test_add_func ("/curve/special/tangents", test_curve_tangents);
   g_test_add_func ("/curve/special/degenerate-tangents", test_curve_degenerate_tangents);
   g_test_add_func ("/curve/special/crossing", test_curve_crossing);
+  g_test_add_func ("/curve/special/bad-split", test_bad_split);
 
   return g_test_run ();
 }

testsuite/gsk/curve.c

@@ -281,16 +281,29 @@ test_curve_decompose_into_cubic (void)
 static void
 test_curve_split (void)
 {
-  for (int i = 0; i < 100; i++)
+  for (int i = 0; i < 1000; i++)
     {
       GskCurve c;
       GskCurve c1, c2;
       graphene_point_t p;
       graphene_vec2_t t, t1, t2;
+      float tt;
+      float l, l1, l2;
 
       init_random_curve (&c);
 
-      gsk_curve_split (&c, 0.5, &c1, &c2);
+      tt = g_test_rand_double_range (0, 1);
+
+      if (tt == 0 || tt == 1)
+        continue;
+
+      if (g_test_verbose ())
+        g_print ("curve %s\nt %g\n", gsk_curve_to_string (&c), tt);
+
+      gsk_curve_split (&c, tt, &c1, &c2);
+
+      if (g_test_verbose ())
+        g_print ("c1 %s\nc2 %s\n", gsk_curve_to_string (&c1), gsk_curve_to_string (&c2));
 
       g_assert_true (c1.op == c.op);
       g_assert_true (c2.op == c.op);
@@ -301,8 +314,9 @@ test_curve_split (void)
                                           gsk_curve_get_start_point (&c2), 0.005));
       g_assert_true (graphene_point_near (gsk_curve_get_end_point (&c),
                                           gsk_curve_get_end_point (&c2), 0.005));
-      gsk_curve_get_point (&c, 0.5, &p);
-      gsk_curve_get_tangent (&c, 0.5, &t);
+
+      gsk_curve_get_point (&c, tt, &p);
+      gsk_curve_get_tangent (&c, tt, &t);
       g_assert_true (graphene_point_near (gsk_curve_get_end_point (&c1), &p, 0.005));
       g_assert_true (graphene_point_near (gsk_curve_get_start_point (&c2), &p, 0.005));
 
@@ -317,6 +331,14 @@ test_curve_split (void)
       gsk_curve_get_end_tangent (&c, &t1);
       gsk_curve_get_end_tangent (&c2, &t2);
       g_assert_true (graphene_vec2_near (&t1, &t2, 0.005));
+
+      l = gsk_curve_get_length (&c);
+      l1 = gsk_curve_get_length (&c1);
+      l2 = gsk_curve_get_length (&c2);
+
+      g_print ("l %g l1 %g l2 %g\n", l, l1, l2);
+
+      g_assert_cmpfloat_with_epsilon (l, l1 + l2, 0.1);
     }
 }
 

testsuite/gsk/measure-special-cases.c

@@ -0,0 +1,272 @@
+/*
+ * 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 <gtk/gtk.h>
+
+
+static void
+test_basics (void)
+{
+  GskPath *path;
+  GskPathMeasure *measure;
+  GskPathPoint point, point1;
+  float epsilon = 0.001;
+  float length;
+
+  path = gsk_path_parse ("M 0 0 L 100 0 C 100 100 200 100 200 0");
+  measure = gsk_path_measure_new (path);
+
+  gsk_path_measure_get_point (measure, 0, &point);
+  gsk_path_get_start_point (path, &point1);
+  g_assert_true (gsk_path_point_equal (&point, &point1));
+
+  g_assert_cmpfloat_with_epsilon (gsk_path_point_get_distance (measure, &point), 0, epsilon);
+
+  gsk_path_measure_get_point (measure, 50, &point);
+  g_assert_cmpfloat_with_epsilon (gsk_path_point_get_distance (measure, &point), 50, epsilon);
+
+  gsk_path_measure_get_point (measure, 100, &point);
+  g_assert_cmpfloat_with_epsilon (gsk_path_point_get_distance (measure, &point), 100, epsilon);
+
+  gsk_path_measure_get_point (measure, 150, &point);
+  g_assert_cmpfloat_with_epsilon (gsk_path_point_get_distance (measure, &point), 150, epsilon);
+
+  length = gsk_path_measure_get_length (measure);
+  gsk_path_measure_get_point (measure, length, &point);
+  gsk_path_get_end_point (path, &point1);
+  g_assert_true (gsk_path_point_equal (&point, &point1));
+
+  g_assert_cmpfloat_with_epsilon (gsk_path_point_get_distance (measure, &point), length, epsilon);
+
+  gsk_path_measure_unref (measure);
+  gsk_path_unref (path);
+}
+
+static void
+test_bad_split (void)
+{
+  GskPath *path, *path1;
+  GskPathMeasure *measure, *measure1;
+  GskPathBuilder *builder;
+  float split, length, epsilon;
+  GskPathPoint point1, point2;
+
+  /* An example that was isolated from the /path/segment test path.c
+   * It shows how uneven parametrization of cubics can lead to bad
+   * lengths reported by the measure.
+   */
+
+  path = gsk_path_parse ("M 0 0 C 2 0 4 0 4 0");
+
+  measure = gsk_path_measure_new (path);
+  split = 2.962588;
+  length = gsk_path_measure_get_length (measure);
+  epsilon = MAX (length / 256, 1.f / 1024);
+
+  gsk_path_get_start_point (path, &point1);
+  gsk_path_measure_get_point (measure, split, &point2);
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_segment (builder, path, &point1, &point2);
+  path1 = gsk_path_builder_free_to_path (builder);
+  measure1 = gsk_path_measure_new (path1);
+
+  g_assert_cmpfloat_with_epsilon (split, gsk_path_measure_get_length (measure1), epsilon);
+
+  gsk_path_measure_unref (measure1);
+  gsk_path_unref (path1);
+  gsk_path_measure_unref (measure);
+  gsk_path_unref (path);
+}
+
+static void
+test_rect (void)
+{
+  GskPathBuilder *builder;
+  GskPath *path;
+  GskPathMeasure *measure;
+  GskPathPoint point;
+  graphene_point_t p;
+  graphene_vec2_t tangent, expected_tangent;
+  float length;
+  gboolean ret;
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (0, 0, 100, 50));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 300);
+
+#define TEST_POS_AT(distance, X, Y) \
+  ret = gsk_path_measure_get_point (measure, distance, &point); \
+  g_assert_true (ret); \
+  gsk_path_point_get_position (path, &point, &p); \
+  g_assert_true (graphene_point_near (&p, &GRAPHENE_POINT_INIT (X, Y), 0.01)); \
+  ret = gsk_path_get_closest_point (path, &GRAPHENE_POINT_INIT (X, Y), INFINITY, &point); \
+  g_assert_true (ret); \
+  if (distance < length) \
+    g_assert_true (fabs (gsk_path_point_get_distance (measure, &point) - distance) < 0.01); \
+  else \
+    g_assert_true (fabs (gsk_path_point_get_distance (measure, &point)) < 0.01); \
+  gsk_path_point_get_position (path, &point, &p); \
+  g_assert_true (graphene_point_near (&p, &GRAPHENE_POINT_INIT (X, Y), 0.01)); \
+
+#define TEST_TANGENT_AT(distance, x1, y1, x2, y2) \
+  ret = gsk_path_measure_get_point (measure, distance, &point); \
+  g_assert_true (ret); \
+  gsk_path_point_get_tangent (path, &point, GSK_PATH_START, &tangent); \
+  g_assert_true (graphene_vec2_near (&tangent, graphene_vec2_init (&expected_tangent, x1, y1), 0.01)); \
+  gsk_path_point_get_tangent (path, &point, GSK_PATH_END, &tangent); \
+  g_assert_true (graphene_vec2_near (&tangent, graphene_vec2_init (&expected_tangent, x2, y2), 0.01)); \
+
+#define TEST_POS_AT2(distance, X, Y, expected_distance) \
+  ret = gsk_path_measure_get_point (measure, distance, &point); \
+  g_assert_true (ret); \
+  gsk_path_point_get_position (path, &point, &p); \
+  g_assert_true (graphene_point_near (&p, &GRAPHENE_POINT_INIT (X, Y), 0.01)); \
+  ret = gsk_path_get_closest_point (path, &GRAPHENE_POINT_INIT (X, Y), INFINITY, &point); \
+  g_assert_true (ret); \
+  g_assert_true (fabs (gsk_path_point_get_distance (measure, &point) - expected_distance) < 0.01); \
+  gsk_path_point_get_position (path, &point, &p); \
+  g_assert_true (graphene_point_near (&p, &GRAPHENE_POINT_INIT (X, Y), 0.01)); \
+
+  TEST_POS_AT (0, 0, 0)
+  TEST_POS_AT (25, 25, 0)
+  TEST_POS_AT (100, 100, 0)
+  TEST_POS_AT (110, 100, 10)
+  TEST_POS_AT (150, 100, 50)
+  TEST_POS_AT (175, 75, 50)
+  TEST_POS_AT (250, 0, 50)
+  TEST_POS_AT (260, 0, 40)
+  TEST_POS_AT2 (300, 0, 0, 0)
+
+  TEST_TANGENT_AT (0, 0, -1, 1, 0)
+  TEST_TANGENT_AT (50, 1, 0, 1, 0)
+  TEST_TANGENT_AT (100, 1, 0, 0, 1)
+  TEST_TANGENT_AT (125, 0, 1, 0, 1)
+  TEST_TANGENT_AT (150, 0, 1, -1, 0)
+  TEST_TANGENT_AT (200, -1, 0, -1, 0)
+  TEST_TANGENT_AT (250, -1, 0, 0, -1)
+  TEST_TANGENT_AT (275, 0, -1, 0, -1)
+
+  gsk_path_measure_unref (measure);
+  gsk_path_unref (path);
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (100, 50, -100, -50));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 300);
+
+  TEST_POS_AT (0, 100, 50)
+  TEST_POS_AT (25, 75, 50)
+  TEST_POS_AT (100, 0, 50)
+  TEST_POS_AT (110, 0, 40)
+  TEST_POS_AT (150, 0, 0)
+  TEST_POS_AT (175, 25, 0)
+  TEST_POS_AT (250, 100, 0)
+  TEST_POS_AT (260, 100, 10)
+  TEST_POS_AT (300, 100, 50)
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (100, 0, -100, 50));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 300);
+
+  TEST_POS_AT (0, 100, 0)
+  TEST_POS_AT (25, 75, 0)
+  TEST_POS_AT (100, 0, 0)
+  TEST_POS_AT (110, 0, 10)
+  TEST_POS_AT (150, 0, 50)
+  TEST_POS_AT (175, 25, 50)
+  TEST_POS_AT (250, 100, 50)
+  TEST_POS_AT (260, 100, 40)
+  TEST_POS_AT (300, 100, 0)
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (0, 0, 100, 0));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 200);
+
+  TEST_POS_AT2 (0, 0, 0, 0)
+  TEST_POS_AT2 (25, 25, 0, 25)
+  TEST_POS_AT2 (100, 100, 0, 100)
+  TEST_POS_AT2 (110, 90, 0, 90)
+  TEST_POS_AT2 (200, 0, 0, 0)
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (100, 0, -100, 0));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 200);
+
+  /* These cases are ambiguous */
+  TEST_POS_AT2 (0, 100, 0, 0)
+  TEST_POS_AT2 (25, 75, 0, 25)
+  TEST_POS_AT2 (100, 0, 0, 100)
+  TEST_POS_AT2 (110, 10, 0, 110)
+  TEST_POS_AT2 (200, 100, 0, 0)
+
+  builder = gsk_path_builder_new ();
+  gsk_path_builder_add_rect (builder, &GRAPHENE_RECT_INIT (0, 100, 0, -100));
+  path = gsk_path_builder_free_to_path (builder);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  g_assert_true (length == 200);
+
+  /* These cases are ambiguous */
+  TEST_POS_AT2 (0, 0, 100, 0)
+  TEST_POS_AT2 (25, 0, 75, 25)
+  TEST_POS_AT2 (100, 0, 0, 100)
+  TEST_POS_AT2 (110, 0, 10, 110)
+  TEST_POS_AT2 (200, 0, 100, 0)
+
+#undef TEST_POS_AT
+#undef TEST_POS_AT2
+#undef TEST_TANGENT_AT
+
+  gsk_path_measure_unref (measure);
+  gsk_path_unref (path);
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  gtk_test_init (&argc, &argv, NULL);
+
+  g_test_add_func ("/measure/basics", test_basics);
+  g_test_add_func ("/measure/bad-split", test_bad_split);
+  g_test_add_func ("/measure/rect", test_rect);
+
+  return g_test_run ();
+}

testsuite/gsk/measure.c

@@ -0,0 +1,555 @@
+/*
+ * 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 <gtk/gtk.h>
+
+static GskPath *
+create_random_degenerate_path (guint max_contours)
+{
+#define N_DEGENERATE_PATHS 14
+  GskPathBuilder *builder;
+  guint i;
+
+  builder = gsk_path_builder_new ();
+
+  switch (g_test_rand_int_range (0, N_DEGENERATE_PATHS))
+  {
+    case 0:
+      /* empty path */
+      break;
+
+    case 1:
+      /* a single point */
+      gsk_path_builder_move_to (builder, 
+                                g_test_rand_double_range (-1000, 1000),
+                                g_test_rand_double_range (-1000, 1000));
+      break;
+
+    case 2:
+      /* N points */
+      for (i = 0; i < MIN (10, max_contours); i++)
+        {
+          gsk_path_builder_move_to (builder, 
+                                    g_test_rand_double_range (-1000, 1000),
+                                    g_test_rand_double_range (-1000, 1000));
+        }
+      break;
+
+    case 3:
+      /* 1 closed point */
+      gsk_path_builder_move_to (builder, 
+                                g_test_rand_double_range (-1000, 1000),
+                                g_test_rand_double_range (-1000, 1000));
+      gsk_path_builder_close (builder);
+      break;
+
+    case 4:
+      /* the same point closed N times */
+      gsk_path_builder_move_to (builder, 
+                                g_test_rand_double_range (-1000, 1000),
+                                g_test_rand_double_range (-1000, 1000));
+      for (i = 0; i < MIN (10, max_contours); i++)
+        {
+          gsk_path_builder_close (builder);
+        }
+      break;
+
+    case 5:
+      /* a zero-width and zero-height rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      0, 0));
+      break;
+
+    case 6:
+      /* a zero-width rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      0,
+                                                      g_test_rand_double_range (-1000, 1000)));
+      break;
+
+    case 7:
+      /* a zero-height rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      0));
+      break;
+
+    case 8:
+      /* a negative-size rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 0),
+                                                      g_test_rand_double_range (-1000, 0)));
+      break;
+
+    case 9:
+      /* an absolutely random rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000)));
+      break;
+
+    case 10:
+      /* an absolutely random rect */
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000)));
+      break;
+
+    case 11:
+      /* an absolutely random circle */
+      gsk_path_builder_add_circle (builder,
+                                   &GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                         g_test_rand_double_range (-1000, 1000)),
+                                   g_test_rand_double_range (1, 1000));
+      break;
+
+    case 12:
+      /* a zero-length line */
+      {
+        graphene_point_t point = GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000));
+        gsk_path_builder_move_to (builder, point.x, point.y);
+        gsk_path_builder_line_to (builder, point.x, point.y);
+      }
+      break;
+
+    case 13:
+      /* a curve with start == end */
+      {
+        graphene_point_t point = GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000));
+        gsk_path_builder_move_to (builder, point.x, point.y);
+        gsk_path_builder_cubic_to (builder,
+                                   g_test_rand_double_range (-1000, 1000),
+                                   g_test_rand_double_range (-1000, 1000),
+                                   g_test_rand_double_range (-1000, 1000),
+                                   g_test_rand_double_range (-1000, 1000),
+                                   point.x, point.y);
+      }
+      break;
+
+    case N_DEGENERATE_PATHS:
+    default:
+      g_assert_not_reached ();
+  }
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+static GskPath *
+create_random_path (guint max_contours);
+
+static void
+add_shape_contour (GskPathBuilder *builder)
+{
+#define N_SHAPE_CONTOURS 3
+  switch (g_test_rand_int_range (0, N_SHAPE_CONTOURS))
+  {
+    case 0:
+      gsk_path_builder_add_rect (builder,
+                                 &GRAPHENE_RECT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (-1000, 1000),
+                                                      g_test_rand_double_range (1, 1000),
+                                                      g_test_rand_double_range (1, 1000)));
+      break;
+
+    case 1:
+      gsk_path_builder_add_circle (builder,
+                                   &GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                         g_test_rand_double_range (-1000, 1000)),
+                                   g_test_rand_double_range (1, 1000));
+      break;
+
+    case 2:
+      {
+        GskPath *path = create_random_path (1);
+        gsk_path_builder_add_path (builder, path);
+        gsk_path_unref (path);
+      }
+      break;
+
+    case N_SHAPE_CONTOURS:
+    default:
+      g_assert_not_reached ();
+      break;
+  }
+}
+
+static void
+add_standard_contour (GskPathBuilder *builder)
+{
+  guint i, n;
+
+  if (g_test_rand_bit ())
+    {
+      if (g_test_rand_bit ())
+        gsk_path_builder_move_to (builder,
+                                  g_test_rand_double_range (-1000, 1000),
+                                  g_test_rand_double_range (-1000, 1000));
+      else
+        gsk_path_builder_rel_move_to (builder,
+                                      g_test_rand_double_range (-1000, 1000),
+                                      g_test_rand_double_range (-1000, 1000));
+    }
+
+  /* that 20 is random, but should be enough to get some
+   * crazy self-intersecting shapes */
+  n = g_test_rand_int_range (1, 20);
+  for (i = 0; i < n; i++)
+    {
+      switch (g_test_rand_int_range (0, 6))
+      {
+        case 0:
+          gsk_path_builder_line_to (builder,
+                                    g_test_rand_double_range (-1000, 1000),
+                                    g_test_rand_double_range (-1000, 1000));
+          break;
+
+        case 1:
+          gsk_path_builder_rel_line_to (builder,
+                                        g_test_rand_double_range (-1000, 1000),
+                                        g_test_rand_double_range (-1000, 1000));
+          break;
+
+        case 2:
+          gsk_path_builder_quad_to (builder,
+                                    g_test_rand_double_range (-1000, 1000),
+                                    g_test_rand_double_range (-1000, 1000),
+                                    g_test_rand_double_range (-1000, 1000),
+                                    g_test_rand_double_range (-1000, 1000));
+          break;
+
+        case 3:
+          gsk_path_builder_rel_quad_to (builder,
+                                        g_test_rand_double_range (-1000, 1000),
+                                        g_test_rand_double_range (-1000, 1000),
+                                        g_test_rand_double_range (-1000, 1000),
+                                        g_test_rand_double_range (-1000, 1000));
+          break;
+
+        case 4:
+          gsk_path_builder_cubic_to (builder,
+                                     g_test_rand_double_range (-1000, 1000),
+                                     g_test_rand_double_range (-1000, 1000),
+                                     g_test_rand_double_range (-1000, 1000),
+                                     g_test_rand_double_range (-1000, 1000),
+                                     g_test_rand_double_range (-1000, 1000),
+                                     g_test_rand_double_range (-1000, 1000));
+          break;
+
+        case 5:
+          gsk_path_builder_rel_cubic_to (builder,
+                                         g_test_rand_double_range (-1000, 1000),
+                                         g_test_rand_double_range (-1000, 1000),
+                                         g_test_rand_double_range (-1000, 1000),
+                                         g_test_rand_double_range (-1000, 1000),
+                                         g_test_rand_double_range (-1000, 1000),
+                                         g_test_rand_double_range (-1000, 1000));
+          break;
+
+        default:
+          g_assert_not_reached();
+          break;
+      }
+    }
+
+  if (g_test_rand_bit ())
+    gsk_path_builder_close (builder);
+}
+
+static GskPath *
+create_random_path (guint max_contours)
+{
+  GskPathBuilder *builder;
+  guint i, n;
+
+  /* 5% chance for a weird shape */
+  if (!g_test_rand_int_range (0, 20))
+    return create_random_degenerate_path (max_contours);
+
+  builder = gsk_path_builder_new ();
+  n = g_test_rand_int_range (1, 10);
+  n = MIN (n, max_contours);
+
+  for (i = 0; i < n; i++)
+    {
+      /* 2/3 of shapes are standard contours */
+      if (g_test_rand_int_range (0, 3))
+        add_standard_contour (builder);
+      else
+        add_shape_contour (builder);
+    }
+
+  return gsk_path_builder_free_to_path (builder);
+}
+
+static void
+test_roundtrip (void)
+{
+  GskPath *path;
+  GskPathMeasure *measure;
+  float length, seg_length;
+  int i;
+  GskPathPoint point;
+  float epsilon = 0.5;
+
+  path = create_random_path (10);
+  measure = gsk_path_measure_new (path);
+  length = gsk_path_measure_get_length (measure);
+
+  for (i = 0; i <= 100; i++)
+    {
+      seg_length = length * i / 100.0f;
+
+      gsk_path_measure_get_point (measure, seg_length, &point);
+
+      g_assert_cmpfloat_with_epsilon (seg_length, gsk_path_point_get_distance (measure, &point), epsilon);
+    }
+
+  gsk_path_measure_unref (measure);
+  gsk_path_unref (path);
+}
+
+static void
+test_get_point (void)
+{
+  static const guint max_contours = 5;
+  static const float tolerance = 1.0;
+  GskPath *path;
+  GskPathMeasure *measure;
+  GskPathPoint point;
+  guint n_discontinuities;
+  float length, offset, last_offset;
+  graphene_point_t p, last_point;
+  guint i, j;
+  gboolean ret;
+
+  for (i = 0; i < 10; i++)
+    {
+      path = create_random_path (max_contours);
+      measure = gsk_path_measure_new_with_tolerance (path, tolerance);
+      length = gsk_path_measure_get_length (measure);
+      n_discontinuities = 0;
+
+      ret = gsk_path_measure_get_point (measure, 0, &point);
+      if (!ret)
+        {
+          g_assert_true (gsk_path_is_empty (path));
+          continue;
+        }
+      gsk_path_point_get_position (path, &point, &last_point);
+
+      /* FIXME: anything we can test with tangents here? */
+      last_offset = 0;
+
+      for (j = 1; j <= 1024; j++)
+        {
+          offset = length * j / 1024;
+          ret = gsk_path_measure_get_point (measure, offset, &point);
+          g_assert_true (ret);
+          gsk_path_point_get_position (path, &point, &p);
+
+          if (graphene_point_distance (&last_point, &p, NULL, NULL) > 2 * (offset - last_offset))
+            {
+              n_discontinuities++;
+              g_assert_cmpint (n_discontinuities, <, max_contours);
+            }
+
+          last_offset = offset;
+          last_point = p;
+        }
+
+      gsk_path_measure_unref (measure);
+      gsk_path_unref (path);
+    }
+}
+
+static void
+test_closest_point (void)
+{
+  static const float tolerance = 0.5;
+  GskPath *path, *path1, *path2;
+  GskPathMeasure *measure, *measure1, *measure2;
+  GskPathBuilder *builder;
+  GskPathPoint point;
+  guint i, j;
+  gboolean ret;
+
+  if (!g_test_slow ())
+    {
+      g_test_skip ("Skipping slow test");
+      return;
+    }
+
+  for (i = 0; i < 10; i++)
+    {
+      path1 = create_random_path (G_MAXUINT);
+      measure1 = gsk_path_measure_new_with_tolerance (path1, tolerance);
+      path2 = create_random_path (G_MAXUINT);
+      measure2 = gsk_path_measure_new_with_tolerance (path2, tolerance);
+
+      builder = gsk_path_builder_new ();
+      gsk_path_builder_add_path (builder, path1);
+      gsk_path_builder_add_path (builder, path2);
+      path = gsk_path_builder_free_to_path (builder);
+      measure = gsk_path_measure_new_with_tolerance (path, tolerance);
+
+      for (j = 0; j < 100; j++)
+        {
+          graphene_point_t test = GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                       g_test_rand_double_range (-1000, 1000));
+          graphene_point_t p1, p2, p;
+          graphene_vec2_t t1, t2, t;
+          float offset1, offset2, offset;
+          float distance1, distance2, distance;
+
+          offset1 = offset2 = offset = 0;
+          distance1 = distance2 = distance = 0;
+          ret = gsk_path_get_closest_point (path1, &test, INFINITY, &point);
+          g_assert_true (ret);
+
+          gsk_path_point_get_position (path1, &point, &p1);
+          gsk_path_point_get_tangent (path1, &point, GSK_PATH_END, &t1);
+          offset1 = gsk_path_point_get_distance (measure1, &point);
+          distance1 = graphene_point_distance (&p1, &test, NULL, NULL);
+
+          ret = gsk_path_get_closest_point (path2, &test, INFINITY, &point);
+          g_assert_true (ret);
+
+          gsk_path_point_get_position (path2, &point, &p2);
+          gsk_path_point_get_tangent (path2, &point, GSK_PATH_END, &t2);
+          offset2 = gsk_path_point_get_distance (measure2, &point);
+          distance2 = graphene_point_distance (&p2, &test, NULL, NULL);
+
+          ret = gsk_path_get_closest_point (path, &test, INFINITY, &point);
+          g_assert_true (ret);
+
+          gsk_path_point_get_position (path, &point, &p);
+          gsk_path_point_get_tangent (path, &point, GSK_PATH_END, &t);
+          offset = gsk_path_point_get_distance (measure, &point);
+          distance = graphene_point_distance (&p, &test, NULL, NULL);
+
+          if (distance1 == distance)
+            {
+              g_assert_cmpfloat (distance1, ==, distance);
+              g_assert_cmpfloat (p1.x, ==, p.x);
+              g_assert_cmpfloat (p1.y, ==, p.y);
+              g_assert_cmpfloat (offset1, ==, offset);
+              g_assert_true (graphene_vec2_equal (&t1, &t));
+            }
+          else
+            {
+              g_assert_cmpfloat (distance2, ==, distance);
+              g_assert_cmpfloat (p2.x, ==, p.x);
+              g_assert_cmpfloat (p2.y, ==, p.y);
+              g_assert_cmpfloat_with_epsilon (offset2 + gsk_path_measure_get_length (measure1), offset, MAX (G_MINFLOAT, offset / 1024));
+              g_assert_true (graphene_vec2_equal (&t2, &t));
+            }
+        }
+
+      gsk_path_measure_unref (measure2);
+      gsk_path_measure_unref (measure1);
+      gsk_path_measure_unref (measure);
+      gsk_path_unref (path2);
+      gsk_path_unref (path1);
+      gsk_path_unref (path);
+    }
+}
+
+static void
+test_closest_point_for_point (void)
+{
+  static const float tolerance = 0.5;
+  GskPath *path;
+  GskPathMeasure *measure;
+  GskPathPoint point;
+  float length, offset, distance;
+  graphene_point_t p, closest_point;
+  guint i, j;
+  gboolean ret;
+
+  if (!g_test_slow ())
+    {
+      g_test_skip ("Skipping slow test");
+      return;
+    }
+
+  for (i = 0; i < 100; i++)
+    {
+      path = create_random_path (G_MAXUINT);
+      if (gsk_path_is_empty (path))
+        {
+          /* empty paths have no closest point to anything */
+          gsk_path_unref (path);
+          continue;
+        }
+
+      measure = gsk_path_measure_new_with_tolerance (path, tolerance);
+      length = gsk_path_measure_get_length (measure);
+
+      for (j = 0; j < 100; j++)
+        {
+          offset = g_test_rand_double_range (0, length);
+          ret = gsk_path_measure_get_point (measure, offset, &point);
+          g_assert_true (ret);
+          gsk_path_point_get_position (path, &point, &p);
+          ret = gsk_path_get_closest_point (path, &p, 2 * tolerance, &point);
+          g_assert_true (ret);
+          gsk_path_point_get_position (path, &point, &closest_point);
+          //closest_offset = gsk_path_point_get_distance (measure, &point);
+          distance = graphene_point_distance (&p, &closest_point, NULL, NULL);
+
+          /* should be given due to the TRUE return above, but who knows... */
+          g_assert_cmpfloat (distance, <=, 2 * tolerance);
+          g_assert_cmpfloat (graphene_point_distance (&p, &closest_point, NULL, NULL), <=, 2 * tolerance);
+          /* we can't check offsets here, since we might hit self-intersections
+          g_assert_cmpfloat_with_epsilon (closest_offset, offset, 2 * tolerance);
+          */
+        }
+
+      gsk_path_measure_unref (measure);
+      gsk_path_unref (path);
+    }
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  gtk_test_init (&argc, &argv, NULL);
+
+  g_test_add_func ("/measure/roundtrip", test_roundtrip);
+  g_test_add_func ("/measure/get_point", test_get_point);
+  g_test_add_func ("/measure/closest_point", test_closest_point);
+  g_test_add_func ("/measure/closest_point_for_point", test_closest_point_for_point);
+
+  return g_test_run ();
+}

testsuite/gsk/meson.build

@@ -371,6 +371,8 @@ tests = [
   ['shader'],
   ['path'],
   ['path-special-cases'],
+  ['measure'],
+  ['measure-special-cases'],
 ]
 
 test_cargs = []

testsuite/gsk/path-special-cases.c

@@ -443,7 +443,6 @@ test_path_point (void)
   gsk_path_point_get_tangent (path, &point, GSK_PATH_END, &t2);
   curvature = gsk_path_point_get_curvature (path, &point, &center);
 
-  g_print ("%g %g\n", graphene_vec2_get_x (&t1), graphene_vec2_get_y (&t1));
   g_assert_true (graphene_point_equal (&pos, &GRAPHENE_POINT_INIT (100, 100)));
   g_assert_true (graphene_vec2_equal (&t1, graphene_vec2_y_axis ()));
   graphene_vec2_negate (graphene_vec2_x_axis (), &mx);
@@ -453,6 +452,106 @@ test_path_point (void)
   gsk_path_unref (path);
 }
 
+/* Test that gsk_path_builder_add_segment yields the expected results */
+static void
+test_path_segments (void)
+{
+  struct {
+    const char *path;
+    graphene_point_t p1;
+    graphene_point_t p2;
+    const char *result;
+  } tests[] = {
+    {
+      "M 0 0 L 100 0 L 50 50 Z",
+      { 100, 0 },
+      { 50, 50 },
+      "M 100 0 L 50 50"
+    },
+    {
+      "M 0 0 L 100 0 L 50 50 Z",
+      { 50, 0 },
+      { 70, 0 },
+      "M 50 0 L 70 0"
+    },
+    {
+      "M 0 0 L 100 0 L 50 50 Z",
+      { 70, 0 },
+      { 50, 0 },
+      "M 70 0 L 100 0 L 50 50 L 0 0 L 50 0"
+    },
+    {
+      "M 0 0 L 100 0 L 50 50 Z",
+      { 50, 0 },
+      { 50, 50 },
+      "M 50 0 L 100 0 L 50 50"
+    },
+    {
+      "M 0 0 L 100 0 L 50 50 Z",
+      { 100, 0 },
+      { 100, 0 },
+      "M 100 0 L 50 50 L 0 0 L 100 0"
+    }
+  };
+
+  for (unsigned int i = 0; i < G_N_ELEMENTS (tests); i++)
+    {
+      GskPath *path;
+      GskPathPoint p1, p2;
+      GskPathBuilder *builder;
+      GskPath *result;
+      char *str;
+
+      path = gsk_path_parse (tests[i].path);
+      g_assert_true (gsk_path_get_closest_point (path, &tests[i].p1, INFINITY, &p1));
+      g_assert_true (gsk_path_get_closest_point (path, &tests[i].p2, INFINITY, &p2));
+
+      builder = gsk_path_builder_new ();
+      gsk_path_builder_add_segment (builder, path, &p1, &p2);
+      result = gsk_path_builder_free_to_path (builder);
+      str = gsk_path_to_string (result);
+
+      g_assert_cmpstr (str, ==, tests[i].result);
+
+      g_free (str);
+      gsk_path_unref (path);
+    }
+}
+
+static void
+test_bad_in_fill (void)
+{
+  GskPath *path;
+  gboolean inside;
+
+  /* A fat Cantarell W */
+  path = gsk_path_parse ("M -2 694 M 206.1748046875 704 L 390.9371337890625 704 L 551.1888427734375 99.5035400390625 L 473.0489501953125 99.5035400390625 L 649.1048583984375 704 L 828.965087890625 704 L 1028.3077392578125 10 L 857.8111572265625 10 L 710.0489501953125 621.251708984375 L 775.9720458984375 598.426513671875 L 614.5245361328125 14.0489501953125 L 430.2237548828125 14.0489501953125 L 278.6783447265625 602.230712890625 L 330.0909423828125 602.230712890625 L 195.88818359375 10 L 5.7342529296875 10 L 206.1748046875 704 Z");
+
+  /* The midpoint of the right foot of a fat Cantarell X */
+  inside = gsk_path_in_fill (path, &GRAPHENE_POINT_INIT (552.360107, 704.000000), GSK_FILL_RULE_WINDING);
+
+  g_assert_false (inside);
+
+  gsk_path_unref (path);
+}
+
+/* Test that path_in_fill implicitly closes contours. I think this is wrong,
+ * but it is what "everybody" does.
+ */
+static void
+test_unclosed_in_fill (void)
+{
+  GskPath *path;
+
+  path = gsk_path_parse ("M 0 0 L 0 100 L 100 100 L 100 0 Z");
+  g_assert_true (gsk_path_in_fill (path, &GRAPHENE_POINT_INIT (50, 50), GSK_FILL_RULE_WINDING));
+  gsk_path_unref (path);
+
+  path = gsk_path_parse ("M 0 0 L 0 100 L 100 100 L 100 0");
+  g_assert_true (gsk_path_in_fill (path, &GRAPHENE_POINT_INIT (50, 50), GSK_FILL_RULE_WINDING));
+  gsk_path_unref (path);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -463,6 +562,9 @@ main (int argc, char *argv[])
   g_test_add_func ("/path/rect", test_rect_path);
   g_test_add_func ("/path/foreach", test_foreach);
   g_test_add_func ("/path/point", test_path_point);
+  g_test_add_func ("/path/segments", test_path_segments);
+  g_test_add_func ("/measure/bad-in-fill", test_bad_in_fill);
+  g_test_add_func ("/measure/unclosed-in-fill", test_unclosed_in_fill);
 
   return g_test_run ();
 }

testsuite/gsk/path.c

@@ -582,6 +582,166 @@ test_parse (void)
     }
 }
 
+#define N_PATHS 3
+static void
+test_in_fill_union (void)
+{
+  GskPath *path, *paths[N_PATHS];
+  GskPathBuilder *builder;
+  guint i, j, k;
+
+  for (i = 0; i < 100; i++)
+    {
+      builder = gsk_path_builder_new ();
+
+      for (k = 0; k < N_PATHS; k++)
+        {
+          paths[k] = create_random_path (G_MAXUINT);
+          gsk_path_builder_add_path (builder, paths[k]);
+        }
+
+      path = gsk_path_builder_free_to_path (builder);
+
+      for (j = 0; j < 100; j++)
+        {
+          graphene_point_t test = GRAPHENE_POINT_INIT (g_test_rand_double_range (-1000, 1000),
+                                                       g_test_rand_double_range (-1000, 1000));
+          GskFillRule fill_rule;
+
+          for (fill_rule = GSK_FILL_RULE_WINDING; fill_rule <= GSK_FILL_RULE_EVEN_ODD; fill_rule++)
+            {
+              guint n_in_fill = 0;
+              gboolean in_fill;
+
+              for (k = 0; k < N_PATHS; k++)
+                {
+                  if (gsk_path_in_fill (paths[k], &test, GSK_FILL_RULE_EVEN_ODD))
+                    n_in_fill++;
+                }
+
+              in_fill = gsk_path_in_fill (path, &test, GSK_FILL_RULE_EVEN_ODD);
+              switch (fill_rule)
+                {
+                case GSK_FILL_RULE_WINDING:
+                  if (n_in_fill == 0)
+                    g_assert_false (in_fill);
+                  else if (n_in_fill == 1)
+                    g_assert_true (in_fill);
+                  /* else we can't say anything because the winding rule doesn't give enough info */
+                  break;
+
+                case GSK_FILL_RULE_EVEN_ODD:
+                  g_assert_cmpint (in_fill, ==, n_in_fill & 1);
+                  break;
+
+                default:
+                  g_assert_not_reached ();
+                  break;
+                }
+            }
+        }
+
+      gsk_path_unref (path);
+
+      for (k = 0; k < N_PATHS; k++)
+        gsk_path_unref (paths[k]);
+    }
+}
+#undef N_PATHS
+
+/* This is somewhat sucky because using foreach breaks up the contours
+ * (like rects and circles) and replaces everything with the standard
+ * contour.
+ * But at least it extensively tests the standard contour.
+ */
+static gboolean
+rotate_path_cb (GskPathOperation        op,
+                const graphene_point_t *pts,
+                gsize                   n_pts,
+                gpointer                user_data)
+{
+  GskPathBuilder **builders = user_data;
+
+  switch (op)
+  {
+    case GSK_PATH_MOVE:
+      gsk_path_builder_move_to (builders[0], pts[0].x, pts[0].y);
+      gsk_path_builder_move_to (builders[1], pts[0].y, -pts[0].x);
+      break;
+
+    case GSK_PATH_CLOSE:
+      gsk_path_builder_close (builders[0]);
+      gsk_path_builder_close (builders[1]);
+      break;
+
+    case GSK_PATH_LINE:
+      gsk_path_builder_line_to (builders[0], pts[1].x, pts[1].y);
+      gsk_path_builder_line_to (builders[1], pts[1].y, -pts[1].x);
+      break;
+
+    case GSK_PATH_QUAD:
+      gsk_path_builder_quad_to (builders[0], pts[1].x, pts[1].y, pts[2].x, pts[2].y);
+      gsk_path_builder_quad_to (builders[1], pts[1].y, -pts[1].x, pts[2].y, -pts[2].x);
+      break;
+
+    case GSK_PATH_CUBIC:
+      gsk_path_builder_cubic_to (builders[0], pts[1].x, pts[1].y, pts[2].x, pts[2].y, pts[3].x, pts[3].y);
+      gsk_path_builder_cubic_to (builders[1], pts[1].y, -pts[1].x, pts[2].y, -pts[2].x, pts[3].y, -pts[3].x);
+      break;
+
+    default:
+      g_assert_not_reached ();
+      return FALSE;
+  }
+
+  return TRUE;
+}
+
+static void
+test_in_fill_rotated (void)
+{
+  GskPath *path;
+  GskPathBuilder *builders[2];
+  GskPath *paths[2];
+  guint i, j;
+
+#define N_FILL_RULES 2
+  /* if this triggers, you added a new enum value to GskFillRule, so the define above needs
+   * an update */
+  g_assert_null (g_enum_get_value (g_type_class_ref (GSK_TYPE_FILL_RULE), N_FILL_RULES));
+
+  for (i = 0; i < 100; i++)
+    {
+      path = create_random_path (G_MAXUINT);
+      builders[0] = gsk_path_builder_new ();
+      builders[1] = gsk_path_builder_new ();
+      /* Use -1 here because we want all the flags, even future additions */
+      gsk_path_foreach (path, -1, rotate_path_cb, builders);
+      gsk_path_unref (path);
+
+      paths[0] = gsk_path_builder_free_to_path (builders[0]);
+      paths[1] = gsk_path_builder_free_to_path (builders[1]);
+
+      for (j = 0; j < 100; j++)
+        {
+          GskFillRule fill_rule = g_random_int_range (0, N_FILL_RULES);
+          float x = g_test_rand_double_range (-1000, 1000);
+          float y = g_test_rand_double_range (-1000, 1000);
+  
+          g_assert_cmpint (gsk_path_in_fill (paths[0], &GRAPHENE_POINT_INIT (x, y), fill_rule),
+                           ==,
+                           gsk_path_in_fill (paths[1], &GRAPHENE_POINT_INIT (y, -x), fill_rule));
+          g_assert_cmpint (gsk_path_in_fill (paths[0], &GRAPHENE_POINT_INIT (y, x), fill_rule),
+                           ==,
+                           gsk_path_in_fill (paths[1], &GRAPHENE_POINT_INIT (x, -y), fill_rule));
+        }
+
+      gsk_path_unref (paths[0]);
+      gsk_path_unref (paths[1]);
+    }
+#undef N_FILL_RULES
+}
+
 int
 main (int   argc,
       char *argv[])
@@ -590,6 +750,8 @@ main (int   argc,
 
   g_test_add_func ("/path/create", test_create);
   g_test_add_func ("/path/parse", test_parse);
+  g_test_add_func ("/path/in-fill-union", test_in_fill_union);
+  g_test_add_func ("/path/in-fill-rotated", test_in_fill_rotated);
 
   return g_test_run ();
 }

testsuite/gtk/calendar.c

@@ -10,7 +10,7 @@ test_calendar_set_day (void)
 
   cal = gtk_calendar_new ();
 
-  tz = g_time_zone_new_identifier ("MET");
+  tz = g_time_zone_new_identifier ("Europe/Brussels");
   g_assert_nonnull (tz);
   dt = g_date_time_new (tz, 1970, 3, 1, 0, 0, 0);
   g_assert_nonnull (dt);