Files
gtk/demos/gtk-demo/path_fill.c
2020-11-26 03:16:23 +01:00

304 lines
9.5 KiB
C

/* Path/Fill
*
* This demo shows how to use PangoCairo to draw text with more than
* just a single color.
*/
#include <glib/gi18n.h>
#include <gtk/gtk.h>
#include "paintable.h"
#define GTK_TYPE_PATH_PAINTABLE (gtk_path_paintable_get_type ())
G_DECLARE_FINAL_TYPE (GtkPathPaintable, gtk_path_paintable, GTK, PATH_PAINTABLE, GObject)
struct _GtkPathPaintable
{
GObject parent_instance;
int width;
int height;
GskPath *path;
GdkPaintable *background;
};
struct _GtkPathPaintableClass
{
GObjectClass parent_class;
};
static int
gtk_path_paintable_get_intrinsic_width (GdkPaintable *paintable)
{
GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
if (self->background)
return MAX (gdk_paintable_get_intrinsic_width (self->background), self->width);
else
return self->width;
}
static int
gtk_path_paintable_get_intrinsic_height (GdkPaintable *paintable)
{
GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
if (self->background)
return MAX (gdk_paintable_get_intrinsic_height (self->background), self->height);
else
return self->height;
}
static void
gtk_path_paintable_snapshot (GdkPaintable *paintable,
GdkSnapshot *snapshot,
double width,
double height)
{
GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
#if 0
gtk_snapshot_push_fill (snapshot, self->path, GSK_FILL_RULE_WINDING);
#else
GskStroke *stroke = gsk_stroke_new (4.0);
gtk_snapshot_push_stroke (snapshot, self->path, stroke);
gsk_stroke_free (stroke);
#endif
if (self->background)
{
gdk_paintable_snapshot (self->background, snapshot, width, height);
}
else
{
gtk_snapshot_append_linear_gradient (snapshot,
&GRAPHENE_RECT_INIT (0, 0, width, height),
&GRAPHENE_POINT_INIT (0, 0),
&GRAPHENE_POINT_INIT (width, height),
(GskColorStop[8]) {
{ 0.0, { 1.0, 0.0, 0.0, 1.0 } },
{ 0.2, { 1.0, 0.0, 0.0, 1.0 } },
{ 0.3, { 1.0, 1.0, 0.0, 1.0 } },
{ 0.4, { 0.0, 1.0, 0.0, 1.0 } },
{ 0.6, { 0.0, 1.0, 1.0, 1.0 } },
{ 0.7, { 0.0, 0.0, 1.0, 1.0 } },
{ 0.8, { 1.0, 0.0, 1.0, 1.0 } },
{ 1.0, { 1.0, 0.0, 1.0, 1.0 } }
},
8);
}
gtk_snapshot_pop (snapshot);
}
static GdkPaintableFlags
gtk_path_paintable_get_flags (GdkPaintable *paintable)
{
GtkPathPaintable *self = GTK_PATH_PAINTABLE (paintable);
if (self->background)
return gdk_paintable_get_flags (self->background);
else
return GDK_PAINTABLE_STATIC_CONTENTS | GDK_PAINTABLE_STATIC_SIZE;
}
static void
gtk_path_paintable_paintable_init (GdkPaintableInterface *iface)
{
iface->get_intrinsic_width = gtk_path_paintable_get_intrinsic_width;
iface->get_intrinsic_height = gtk_path_paintable_get_intrinsic_height;
iface->snapshot = gtk_path_paintable_snapshot;
iface->get_flags = gtk_path_paintable_get_flags;
}
/* When defining the GType, we need to implement the GdkPaintable interface */
G_DEFINE_TYPE_WITH_CODE (GtkPathPaintable, gtk_path_paintable, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (GDK_TYPE_PAINTABLE,
gtk_path_paintable_paintable_init))
/* Here's the boilerplate for the GObject declaration.
* We don't need to do anything special here, because we keep no
* data of our own.
*/
static void
gtk_path_paintable_class_init (GtkPathPaintableClass *klass)
{
}
static void
gtk_path_paintable_init (GtkPathPaintable *self)
{
}
/* And finally, we add a simple constructor.
* It is declared in the header so that the other examples
* can use it.
*/
GdkPaintable *
gtk_path_paintable_new (GskPath *path,
GdkPaintable *background,
int width,
int height)
{
GtkPathPaintable *self;
self = g_object_new (GTK_TYPE_PATH_PAINTABLE, NULL);
self->path = path;
self->background = background;
if (self->background)
{
g_signal_connect_swapped (self->background, "invalidate-contents", G_CALLBACK (gdk_paintable_invalidate_contents), self);
g_signal_connect_swapped (self->background, "invalidate-size", G_CALLBACK (gdk_paintable_invalidate_size), self);
}
self->width = width;
self->height = height;
return GDK_PAINTABLE (self);
}
void
gtk_path_paintable_set_path (GtkPathPaintable *self,
GskPath *path)
{
g_clear_pointer (&self->path, gsk_path_unref);
self->path = gsk_path_ref (path);
gdk_paintable_invalidate_contents (GDK_PAINTABLE (self));
}
static GskPath *
create_hexagon (GtkWidget *widget)
{
GskPathBuilder *builder;
builder = gsk_path_builder_new ();
gsk_path_builder_move_to (builder, 120, 0);
gsk_path_builder_line_to (builder, 360, 0);
gsk_path_builder_line_to (builder, 480, 208);
gsk_path_builder_line_to (builder, 360, 416);
gsk_path_builder_line_to (builder, 120, 416);
gsk_path_builder_line_to (builder, 0, 208);
gsk_path_builder_close (builder);
return gsk_path_builder_free_to_path (builder);
}
static GskPath *
create_path_from_text (GtkWidget *widget)
{
cairo_surface_t *surface;
cairo_t *cr;
cairo_path_t *path;
PangoLayout *layout;
PangoFontDescription *desc;
GskPath *result;
surface = cairo_recording_surface_create (CAIRO_CONTENT_COLOR_ALPHA, NULL);
cr = cairo_create (surface);
layout = gtk_widget_create_pango_layout (widget, "Pango power!\nPango power!\nPango power!");
desc = pango_font_description_from_string ("sans bold 36");
pango_layout_set_font_description (layout, desc);
pango_font_description_free (desc);
pango_cairo_layout_path (cr, layout);
path = cairo_copy_path_flat (cr);
result = gsk_path_new_from_cairo (path);
cairo_path_destroy (path);
g_object_unref (layout);
cairo_destroy (cr);
cairo_surface_destroy (surface);
return result;
}
static gboolean
update_path (GtkWidget *widget,
GdkFrameClock *frame_clock,
gpointer measure)
{
float progress = gdk_frame_clock_get_frame_time (frame_clock) % (60 * G_USEC_PER_SEC) / (float) (30 * G_USEC_PER_SEC);
GskPathBuilder *builder;
GskPath *path;
graphene_point_t pos;
graphene_vec2_t tangent;
builder = gsk_path_builder_new ();
gsk_path_measure_add_segment (measure,
builder,
progress > 1 ? (progress - 1) * gsk_path_measure_get_length (measure) : 0.0,
(progress < 1 ? progress : 1.0) * gsk_path_measure_get_length (measure));
gsk_path_measure_get_point (measure,
(progress > 1 ? (progress - 1) : progress) * gsk_path_measure_get_length (measure),
&pos,
&tangent);
gsk_path_builder_move_to (builder, pos.x + 5 * graphene_vec2_get_x (&tangent), pos.y + 5 * graphene_vec2_get_y (&tangent));
gsk_path_builder_line_to (builder, pos.x + 3 * graphene_vec2_get_y (&tangent), pos.y + 3 * graphene_vec2_get_x (&tangent));
gsk_path_builder_line_to (builder, pos.x - 3 * graphene_vec2_get_y (&tangent), pos.y - 3 * graphene_vec2_get_x (&tangent));
gsk_path_builder_close (builder);
path = gsk_path_builder_free_to_path (builder);
gtk_path_paintable_set_path (GTK_PATH_PAINTABLE (gtk_picture_get_paintable (GTK_PICTURE (widget))),
path);
gsk_path_unref (path);
return G_SOURCE_CONTINUE;
}
GtkWidget *
do_path_fill (GtkWidget *do_widget)
{
static GtkWidget *window = NULL;
if (!window)
{
GtkWidget *picture;
GdkPaintable *paintable;
GtkMediaStream *stream;
GskPath *path;
graphene_rect_t bounds;
GskPathMeasure *measure;
window = gtk_window_new ();
gtk_window_set_resizable (GTK_WINDOW (window), TRUE);
gtk_window_set_title (GTK_WINDOW (window), "Path Fill");
g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
#if 0
stream = gtk_media_file_new_for_resource ("/images/gtk-logo.webm");
#else
stream = gtk_nuclear_media_stream_new ();
#endif
gtk_media_stream_play (stream);
gtk_media_stream_set_loop (stream, TRUE);
path = create_hexagon (window);
path = create_path_from_text (window);
gsk_path_get_bounds (path, &bounds);
paintable = gtk_path_paintable_new (path,
GDK_PAINTABLE (stream),
bounds.origin.x + bounds.size.width,
bounds.origin.y + bounds.size.height);
picture = gtk_picture_new_for_paintable (paintable);
measure = gsk_path_measure_new (path);
gtk_widget_add_tick_callback (picture, update_path, measure, (GDestroyNotify) gsk_path_measure_unref);
gtk_picture_set_keep_aspect_ratio (GTK_PICTURE (picture), FALSE);
gtk_picture_set_can_shrink (GTK_PICTURE (picture), FALSE);
g_object_unref (paintable);
gtk_window_set_child (GTK_WINDOW (window), picture);
}
if (!gtk_widget_get_visible (window))
gtk_widget_show (window);
else
gtk_window_destroy (GTK_WINDOW (window));
return window;
}