gtk-demo: Show closest point in text-on-path demo

This commit is contained in:
Benjamin Otte
2020-11-25 00:15:15 +01:00
committed by Matthias Clasen
parent 4bcc4529da
commit e8750af295

View File

@@ -1,4 +1,4 @@
/* Path/Text
/* Path/Curved Text
*
* This demo shows how to use GskPath to animate a path along another path.
*/
@@ -28,6 +28,7 @@ struct _GtkPathWidget
graphene_point_t points[4];
guint active_point;
float line_closest;
GskPath *line_path;
GskPathMeasure *line_measure;
@@ -248,7 +249,7 @@ gtk_path_widget_snapshot (GtkWidget *widget,
/* 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_append_color (snapshot, &(GdkRGBA) { 1, 1, 1, 0.5 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
gtk_snapshot_pop (snapshot);
/* draw the text */
@@ -270,14 +271,34 @@ gtk_path_widget_snapshot (GtkWidget *widget,
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);
}
if (self->line_closest >= 0)
{
GskPathBuilder *builder;
graphene_point_t closest;
builder = gsk_path_builder_new ();
gsk_path_measure_get_point (self->line_measure, self->line_closest, &closest, NULL);
gsk_path_builder_add_circle (builder, &closest, POINT_SIZE);
path = gsk_path_builder_free_to_path (builder);
gtk_snapshot_push_fill (snapshot, path, GSK_FILL_RULE_WINDING);
gtk_snapshot_append_color (snapshot, &(GdkRGBA) { 0, 0, 1, 1 }, &GRAPHENE_RECT_INIT (0, 0, width, height));
gtk_snapshot_pop (snapshot);
gsk_path_unref (path);
}
if (self->editable && self->line_path)
{
GskPathBuilder *builder;
/* draw the points */
builder = gsk_path_builder_new ();
@@ -471,6 +492,31 @@ drag_update (GtkGestureDrag *drag,
gtk_widget_queue_draw (GTK_WIDGET (self));
}
static void
pointer_motion (GtkEventControllerMotion *controller,
double x,
double y,
GtkPathWidget *self)
{
gsk_path_measure_get_closest_point_full (self->line_measure,
&GRAPHENE_POINT_INIT (x, y),
INFINITY,
NULL, NULL,
&self->line_closest,
NULL);
gtk_widget_queue_draw (GTK_WIDGET (self));
}
static void
pointer_leave (GtkEventControllerMotion *controller,
GtkPathWidget *self)
{
self->line_closest = -1;
gtk_widget_queue_draw (GTK_WIDGET (self));
}
static void
gtk_path_widget_init (GtkPathWidget *self)
{
@@ -480,9 +526,16 @@ gtk_path_widget_init (GtkPathWidget *self)
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);