gtk2/gsk/gskrenderer.c
2017-12-21 19:12:30 +01:00

849 lines
24 KiB
C

/* GSK - The GTK Scene Kit
*
* 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
* License as published by the Free Software Foundation; either
* version 2 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/>.
*/
/**
* SECTION:GskRenderer
* @Title: GskRenderer
* @Short_description: Renders a scene
*
* #GskRenderer is a class that renders a scene graph defined via a
* tree of #GskRenderNode instances.
*
* Typically you will use a #GskRenderer instance with a #GdkDrawingContext
* associated to a #GdkWindow, and call gsk_renderer_render() with the
* drawing context and the scene to be rendered.
*
* It is necessary to realize a #GskRenderer instance using gsk_renderer_realize()
* before calling gsk_renderer_render(), in order to create the appropriate
* windowing system resources needed to render the scene.
*/
#include "config.h"
#include "gskrendererprivate.h"
#include "gskcairorendererprivate.h"
#include "gskdebugprivate.h"
#include "gl/gskglrendererprivate.h"
#include "gskprofilerprivate.h"
#include "gskrendernodeprivate.h"
#include "gskenumtypes.h"
#include <graphene-gobject.h>
#include <cairo-gobject.h>
#include <gdk/gdk.h>
#ifdef GDK_WINDOWING_X11
#include <gdk/x11/gdkx.h>
#endif
#ifdef GDK_WINDOWING_WAYLAND
#include <gdk/wayland/gdkwayland.h>
#endif
#ifdef GDK_WINDOWING_BROADWAY
#include "gskbroadwayrendererprivate.h"
#endif
#ifdef GDK_RENDERING_VULKAN
#include "gskvulkanrendererprivate.h"
#endif
typedef struct
{
GObject parent_instance;
GskScalingFilter min_filter;
GskScalingFilter mag_filter;
GdkWindow *window;
GdkDrawingContext *drawing_context;
GskRenderNode *root_node;
GdkDisplay *display;
GskProfiler *profiler;
gboolean is_realized : 1;
} GskRendererPrivate;
G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GskRenderer, gsk_renderer, G_TYPE_OBJECT)
enum {
PROP_WINDOW = 1,
PROP_DISPLAY,
PROP_DRAWING_CONTEXT,
N_PROPS
};
static GParamSpec *gsk_renderer_properties[N_PROPS];
#define GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD(obj,method) \
g_critical ("Renderer of type '%s' does not implement GskRenderer::" # method, G_OBJECT_TYPE_NAME (obj))
static gboolean
gsk_renderer_real_realize (GskRenderer *self,
GdkWindow *window,
GError **error)
{
GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD (self, realize);
return FALSE;
}
static void
gsk_renderer_real_unrealize (GskRenderer *self)
{
GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD (self, unrealize);
}
static GdkTexture *
gsk_renderer_real_render_texture (GskRenderer *self,
GskRenderNode *root,
const graphene_rect_t *viewport)
{
GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD (self, render_texture);
return NULL;
}
static GdkDrawingContext *
gsk_renderer_real_begin_draw_frame (GskRenderer *self,
const cairo_region_t *region)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
return gdk_window_begin_draw_frame (priv->window,
NULL,
region);
}
static void
gsk_renderer_real_end_draw_frame (GskRenderer *self,
GdkDrawingContext *context)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
gdk_window_end_draw_frame (priv->window,
context);
}
static void
gsk_renderer_real_render (GskRenderer *self,
GskRenderNode *root)
{
GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD (self, render);
}
static cairo_surface_t *
gsk_renderer_real_create_cairo_surface (GskRenderer *self,
cairo_format_t format,
int width,
int height)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
int scale_factor = priv->window ? gdk_window_get_scale_factor (priv->window) : 1;
int real_width = width * scale_factor;
int real_height = height * scale_factor;
cairo_surface_t *res = cairo_image_surface_create (format, real_width, real_height);
cairo_surface_set_device_scale (res, scale_factor, scale_factor);
return res;
}
static void
gsk_renderer_dispose (GObject *gobject)
{
GskRenderer *self = GSK_RENDERER (gobject);
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
/* We can't just unrealize here because superclasses have already run dispose.
* So we insist that unrealize must be called before unreffing. */
g_assert (!priv->is_realized);
g_clear_object (&priv->profiler);
g_clear_object (&priv->display);
G_OBJECT_CLASS (gsk_renderer_parent_class)->dispose (gobject);
}
static void
gsk_renderer_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GskRenderer *self = GSK_RENDERER (gobject);
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
switch (prop_id)
{
case PROP_DISPLAY:
/* Construct-only */
priv->display = g_value_dup_object (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
gsk_renderer_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GskRenderer *self = GSK_RENDERER (gobject);
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
switch (prop_id)
{
case PROP_WINDOW:
g_value_set_object (value, priv->window);
break;
case PROP_DRAWING_CONTEXT:
g_value_set_object (value, priv->drawing_context);
break;
case PROP_DISPLAY:
g_value_set_object (value, priv->display);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
gsk_renderer_constructed (GObject *gobject)
{
GskRenderer *self = GSK_RENDERER (gobject);
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
if (priv->display == NULL)
{
GdkDisplayManager *manager = gdk_display_manager_get ();
priv->display = gdk_display_manager_get_default_display (manager);
g_assert (priv->display != NULL);
}
G_OBJECT_CLASS (gsk_renderer_parent_class)->constructed (gobject);
}
static void
gsk_renderer_class_init (GskRendererClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
klass->realize = gsk_renderer_real_realize;
klass->unrealize = gsk_renderer_real_unrealize;
klass->begin_draw_frame = gsk_renderer_real_begin_draw_frame;
klass->end_draw_frame = gsk_renderer_real_end_draw_frame;
klass->render = gsk_renderer_real_render;
klass->render_texture = gsk_renderer_real_render_texture;
klass->create_cairo_surface = gsk_renderer_real_create_cairo_surface;
gobject_class->constructed = gsk_renderer_constructed;
gobject_class->set_property = gsk_renderer_set_property;
gobject_class->get_property = gsk_renderer_get_property;
gobject_class->dispose = gsk_renderer_dispose;
/**
* GskRenderer:display:
*
* The #GdkDisplay used by the #GskRenderer.
*
* Since: 3.90
*/
gsk_renderer_properties[PROP_DISPLAY] =
g_param_spec_object ("display",
"Display",
"The GdkDisplay object used by the renderer",
GDK_TYPE_DISPLAY,
G_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_STRINGS);
gsk_renderer_properties[PROP_WINDOW] =
g_param_spec_object ("window",
"Window",
"The window associated to the renderer",
GDK_TYPE_WINDOW,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS);
/**
* GskRenderer:drawing-context:
*
* The drawing context used when rendering.
*
* Since: 3.90
*/
gsk_renderer_properties[PROP_DRAWING_CONTEXT] =
g_param_spec_object ("drawing-context",
"Drawing Context",
"The drawing context used by the renderer",
GDK_TYPE_DRAWING_CONTEXT,
G_PARAM_READABLE |
G_PARAM_STATIC_STRINGS);
g_object_class_install_properties (gobject_class, N_PROPS, gsk_renderer_properties);
}
static void
gsk_renderer_init (GskRenderer *self)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (self);
priv->profiler = gsk_profiler_new ();
}
/**
* gsk_renderer_get_window:
* @renderer: a #GskRenderer
*
* Retrieves the #GdkWindow set using gsk_renderer_realize(). If the renderer
* has not been realized yet, %NULL will be returned.
*
* Returns: (transfer none) (nullable): a #GdkWindow
*
* Since: 3.90
*/
GdkWindow *
gsk_renderer_get_window (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
return priv->window;
}
/*< private >
* gsk_renderer_get_root_node:
* @renderer: a #GskRenderer
*
* Retrieves the #GskRenderNode used by @renderer.
*
* Returns: (transfer none) (nullable): a #GskRenderNode
*/
GskRenderNode *
gsk_renderer_get_root_node (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
return priv->root_node;
}
/*< private >
* gsk_renderer_get_drawing_context:
* @renderer: a #GskRenderer
*
* Retrieves the #GdkDrawingContext used by @renderer.
*
* Returns: (transfer none) (nullable): a #GdkDrawingContext
*/
GdkDrawingContext *
gsk_renderer_get_drawing_context (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
return priv->drawing_context;
}
/**
* gsk_renderer_get_display:
* @renderer: a #GskRenderer
*
* Retrieves the #GdkDisplay used when creating the #GskRenderer.
*
* Returns: (transfer none): a #GdkDisplay
*
* Since: 3.90
*/
GdkDisplay *
gsk_renderer_get_display (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
return priv->display;
}
/*< private >
* gsk_renderer_is_realized:
* @renderer: a #GskRenderer
*
* Checks whether the @renderer is realized or not.
*
* Returns: %TRUE if the #GskRenderer was realized, and %FALSE otherwise
*
* Since: 3.90
*/
gboolean
gsk_renderer_is_realized (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), FALSE);
return priv->is_realized;
}
/**
* gsk_renderer_realize:
* @renderer: a #GskRenderer
* @window: the #GdkWindow renderer will be used on
* @error: return location for an error
*
* Creates the resources needed by the @renderer to render the scene
* graph.
*
* Since: 3.90
*/
gboolean
gsk_renderer_realize (GskRenderer *renderer,
GdkWindow *window,
GError **error)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), FALSE);
g_return_val_if_fail (!gsk_renderer_is_realized (renderer), FALSE);
g_return_val_if_fail (GDK_IS_WINDOW (window), FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
priv->window = g_object_ref (window);
if (!GSK_RENDERER_GET_CLASS (renderer)->realize (renderer, window, error))
{
g_clear_object (&priv->window);
return FALSE;
}
priv->is_realized = TRUE;
return TRUE;
}
/**
* gsk_renderer_unrealize:
* @renderer: a #GskRenderer
*
* Releases all the resources created by gsk_renderer_realize().
*
* Since: 3.90
*/
void
gsk_renderer_unrealize (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_if_fail (GSK_IS_RENDERER (renderer));
if (!priv->is_realized)
return;
GSK_RENDERER_GET_CLASS (renderer)->unrealize (renderer);
priv->is_realized = FALSE;
}
/**
* gsk_renderer_render_texture:
* @renderer: a realized #GdkRenderer
* @root: a #GskRenderNode
* @viewport: (allow-none): the section to draw or %NULL to use @root's bounds
*
* Renders the scene graph, described by a tree of #GskRenderNode instances,
* to a #GdkTexture.
*
* The @renderer will acquire a reference on the #GskRenderNode tree while
* the rendering is in progress, and will make the tree immutable.
*
* If you want to apply any transformations to @root, you should put it into a
* transform node and pass that node instead.
*
* Returns: (transfer full): a #GdkTexture with the rendered contents of @root.
*
* Since: 3.90
*/
GdkTexture *
gsk_renderer_render_texture (GskRenderer *renderer,
GskRenderNode *root,
const graphene_rect_t *viewport)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
graphene_rect_t real_viewport;
GdkTexture *texture;
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
g_return_val_if_fail (priv->is_realized, NULL);
g_return_val_if_fail (GSK_IS_RENDER_NODE (root), NULL);
g_return_val_if_fail (priv->root_node == NULL, NULL);
priv->root_node = gsk_render_node_ref (root);
if (viewport == NULL)
{
gsk_render_node_get_bounds (root, &real_viewport);
viewport = &real_viewport;
}
texture = GSK_RENDERER_GET_CLASS (renderer)->render_texture (renderer, root, viewport);
#ifdef G_ENABLE_DEBUG
if (GSK_DEBUG_CHECK (RENDERER))
{
GString *buf = g_string_new ("*** Texture stats ***\n\n");
gsk_profiler_append_counters (priv->profiler, buf);
g_string_append_c (buf, '\n');
gsk_profiler_append_timers (priv->profiler, buf);
g_string_append_c (buf, '\n');
g_print ("%s\n***\n\n", buf->str);
g_string_free (buf, TRUE);
}
#endif
g_clear_pointer (&priv->root_node, gsk_render_node_unref);
return texture;
}
/**
* gsk_renderer_render:
* @renderer: a #GskRenderer
* @root: a #GskRenderNode
* @context: The drawing context created via gsk_renderer_begin_draw_frame()
*
* Renders the scene graph, described by a tree of #GskRenderNode instances,
* using the given #GdkDrawingContext.
*
* The @renderer will acquire a reference on the #GskRenderNode tree while
* the rendering is in progress.
*
* Since: 3.90
*/
void
gsk_renderer_render (GskRenderer *renderer,
GskRenderNode *root,
GdkDrawingContext *context)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_if_fail (GSK_IS_RENDERER (renderer));
g_return_if_fail (priv->is_realized);
g_return_if_fail (GSK_IS_RENDER_NODE (root));
g_return_if_fail (priv->root_node == NULL);
g_return_if_fail (GDK_IS_DRAWING_CONTEXT (context));
g_return_if_fail (context == priv->drawing_context);
priv->root_node = gsk_render_node_ref (root);
GSK_RENDERER_GET_CLASS (renderer)->render (renderer, root);
#ifdef G_ENABLE_DEBUG
if (GSK_DEBUG_CHECK (RENDERER))
{
GString *buf = g_string_new ("*** Frame stats ***\n\n");
gsk_profiler_append_counters (priv->profiler, buf);
g_string_append_c (buf, '\n');
gsk_profiler_append_timers (priv->profiler, buf);
g_string_append_c (buf, '\n');
g_print ("%s\n***\n\n", buf->str);
g_string_free (buf, TRUE);
}
#endif
g_clear_pointer (&priv->root_node, gsk_render_node_unref);
}
/*< private >
* gsk_renderer_get_profiler:
* @renderer: a #GskRenderer
*
* Retrieves a pointer to the GskProfiler instance of the renderer.
*
* Returns: (transfer none): the profiler
*/
GskProfiler *
gsk_renderer_get_profiler (GskRenderer *renderer)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
return priv->profiler;
}
static GType
get_renderer_for_name (const char *renderer_name)
{
if (renderer_name == NULL)
return G_TYPE_INVALID;
else if (g_ascii_strcasecmp (renderer_name, "cairo") == 0)
return GSK_TYPE_CAIRO_RENDERER;
else if (g_ascii_strcasecmp (renderer_name, "opengl") == 0
|| g_ascii_strcasecmp (renderer_name, "gl") == 0)
return GSK_TYPE_GL_RENDERER;
#ifdef GDK_RENDERING_VULKAN
else if (g_ascii_strcasecmp (renderer_name, "vulkan") == 0)
return GSK_TYPE_VULKAN_RENDERER;
#endif
else if (g_ascii_strcasecmp (renderer_name, "help") == 0)
{
g_print ("Supported arguments for GSK_RENDERER environment variable:\n");
g_print (" cairo - Use the Cairo fallback renderer\n");
g_print (" opengl - Use the default OpenGL renderer\n");
#ifdef GDK_RENDERING_VULKAN
g_print (" vulkan - Use the Vulkan renderer\n");
#endif
g_print (" help - Print this help\n\n");
g_print ("Other arguments will cause a warning and be ignored.\n");
}
else
{
g_warning ("Unrecognized renderer \"%s\". Try GSK_RENDERER=help", renderer_name);
}
return G_TYPE_INVALID;
}
static GType
get_renderer_for_display (GdkWindow *window)
{
GdkDisplay *display = gdk_window_get_display (window);
const char *renderer_name;
renderer_name = g_object_get_data (G_OBJECT (display), "gsk-renderer");
return get_renderer_for_name (renderer_name);
}
static GType
get_renderer_for_env_var (GdkWindow *window)
{
static GType env_var_type = G_TYPE_NONE;
if (env_var_type == G_TYPE_NONE)
{
const char *renderer_name = g_getenv ("GSK_RENDERER");
env_var_type = get_renderer_for_name (renderer_name);
}
return env_var_type;
}
static GType
get_renderer_for_backend (GdkWindow *window)
{
#ifdef GDK_WINDOWING_X11
if (GDK_IS_X11_WINDOW (window))
return GSK_TYPE_GL_RENDERER;
#endif
#ifdef GDK_WINDOWING_WAYLAND
if (GDK_IS_WAYLAND_WINDOW (window))
return GSK_TYPE_GL_RENDERER;
#endif
#ifdef GDK_WINDOWING_BROADWAY
if (GDK_IS_BROADWAY_WINDOW (window))
return GSK_TYPE_BROADWAY_RENDERER;
#endif
return G_TYPE_INVALID;
}
static GType
get_renderer_fallback (GdkWindow *window)
{
return GSK_TYPE_CAIRO_RENDERER;
}
static struct {
gboolean verbose;
GType (* get_renderer) (GdkWindow *window);
} renderer_possibilities[] = {
{ TRUE, get_renderer_for_display },
{ TRUE, get_renderer_for_env_var },
{ FALSE, get_renderer_for_backend },
{ FALSE, get_renderer_fallback },
};
/**
* gsk_renderer_new_for_window:
* @window: a #GdkWindow
*
* Creates an appropriate #GskRenderer instance for the given @window.
*
* The renderer will be realized when it is returned.
*
* Returns: (transfer full) (nullable): a #GskRenderer
*
* Since: 3.90
*/
GskRenderer *
gsk_renderer_new_for_window (GdkWindow *window)
{
GType renderer_type;
GskRenderer *renderer;
GError *error = NULL;
gboolean verbose = FALSE;
guint i;
g_return_val_if_fail (GDK_IS_WINDOW (window), NULL);
for (i = 0; i < G_N_ELEMENTS (renderer_possibilities); i++)
{
renderer_type = renderer_possibilities[i].get_renderer (window);
if (renderer_type == G_TYPE_INVALID)
continue;
/* If a renderer is selected that's marked as verbose, start printing
* information to stdout.
*/
verbose |= renderer_possibilities[i].verbose;
renderer = g_object_new (renderer_type,
"display", gdk_window_get_display (window),
NULL);
if (gsk_renderer_realize (renderer, window, &error))
{
if (verbose || GSK_DEBUG_CHECK (RENDERER))
{
g_print ("Using renderer of type '%s' for display '%s'\n",
G_OBJECT_TYPE_NAME (renderer),
G_OBJECT_TYPE_NAME (window));
}
return renderer;
}
if (verbose || GSK_DEBUG_CHECK (RENDERER))
{
g_print ("Failed to realize renderer of type '%s' for window '%s': %s\n",
G_OBJECT_TYPE_NAME (renderer),
G_OBJECT_TYPE_NAME (window),
error->message);
}
g_object_unref (renderer);
g_clear_error (&error);
}
g_assert_not_reached ();
return NULL;
}
cairo_surface_t *
gsk_renderer_create_cairo_surface (GskRenderer *renderer,
cairo_format_t format,
int width,
int height)
{
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
g_return_val_if_fail (width > 0 && height > 0, NULL);
return GSK_RENDERER_GET_CLASS (renderer)->create_cairo_surface (renderer, format, width, height);
}
/**
* gsk_renderer_begin_draw_frame:
* @renderer: a #GskRenderer
* @region: the #cairo_region_t that you wish to draw
*
* Indicates that you are beginning the process of redrawing @region using
* @renderer, and provides you with a #GdkDrawingContext to use for this.
*
* Returns: (transfer none): a #GdkDrawingContext context that should be used to
* draw the contents of the @renderer. This context is owned by GDK.
*
* Since: 3.90
*/
GdkDrawingContext *
gsk_renderer_begin_draw_frame (GskRenderer *renderer,
const cairo_region_t *region)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_val_if_fail (GSK_IS_RENDERER (renderer), NULL);
g_return_val_if_fail (region != NULL, NULL);
g_return_val_if_fail (priv->drawing_context == NULL, NULL);
if (GSK_RENDER_MODE_CHECK (FULL_REDRAW))
{
cairo_region_t *full_window;
full_window = cairo_region_create_rectangle (&(GdkRectangle) {
0, 0,
gdk_window_get_width (priv->window),
gdk_window_get_height (priv->window)
});
priv->drawing_context = GSK_RENDERER_GET_CLASS (renderer)->begin_draw_frame (renderer, full_window);
cairo_region_destroy (full_window);
}
else
{
priv->drawing_context = GSK_RENDERER_GET_CLASS (renderer)->begin_draw_frame (renderer, region);
}
return priv->drawing_context;
}
/**
* gsk_renderer_end_draw_frame:
* @renderer: a #GskRenderer
* @context: the drawing context returned by the matching call to
* gsk_renderer_begin_draw_frame()
*
* Release the drawning context returned by gsk_renderer_begin_draw_frame().
*
* Calls to gsk_renderer_begin_draw_frame() and gsk_renderer_end_draw_frame()
* must be paired.
*
* Since: 3.90
*/
void
gsk_renderer_end_draw_frame (GskRenderer *renderer,
GdkDrawingContext *context)
{
GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
g_return_if_fail (GSK_IS_RENDERER (renderer));
g_return_if_fail (GDK_IS_DRAWING_CONTEXT (context));
g_return_if_fail (priv->drawing_context == context);
priv->drawing_context = NULL;
GSK_RENDERER_GET_CLASS (renderer)->end_draw_frame (renderer, context);
}