1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef UI_GFX_IMAGE_CAIRO_CACHED_SURFACE_H_
6 #define UI_GFX_IMAGE_CAIRO_CACHED_SURFACE_H_
10 #include "ui/gfx/gfx_export.h"
12 typedef struct _GdkDisplay GdkDisplay;
13 typedef struct _GdkPixbuf GdkPixbuf;
14 typedef struct _GtkWidget GtkWidget;
15 typedef struct _cairo cairo_t;
16 typedef struct _cairo_surface cairo_surface_t;
20 // A helper class that takes a GdkPixbuf* and renders it to the screen. Unlike
21 // gdk_cairo_set_source_pixbuf(), CairoCachedSurface assumes that the pixbuf is
22 // immutable after UsePixbuf() is called and can be sent to the display server
23 // once. From then on, that cached version is used so we don't upload the same
24 // image each and every time we expose.
26 // Most cached surfaces are owned by the GtkThemeService, which associates
27 // them with a certain XDisplay. Some users of surfaces (CustomDrawButtonBase,
28 // for example) own their surfaces instead since they interact with the
29 // ResourceBundle instead of the GtkThemeService.
30 class GFX_EXPORT CairoCachedSurface {
33 ~CairoCachedSurface();
35 // Whether this CairoCachedSurface owns a GdkPixbuf.
40 // Delete all our data.
43 // The dimensions of the underlying pixbuf/surface. (or -1 if invalid.)
47 // Sets the pixbuf that we pass to cairo. Calling UsePixbuf() only derefs the
48 // current pixbuf and surface (if they exist). Actually transfering data to
49 // the X server occurs at SetSource() time. Calling UsePixbuf() should only
50 // be done once as it clears cached data from the X server.
51 void UsePixbuf(GdkPixbuf* pixbuf);
53 // Sets our pixbuf as the active surface starting at (x, y), uploading it in
54 // case we don't have an X backed surface cached.
55 void SetSource(cairo_t* cr, GtkWidget* widget, int x, int y) const;
56 void SetSource(cairo_t* cr, GdkDisplay* display, int x, int y) const;
58 // Performs a mask operation, using this surface as the alpha channel.
59 void MaskSource(cairo_t* cr, GtkWidget* widget, int x, int y) const;
60 void MaskSource(cairo_t* cr, GdkDisplay* display, int x, int y) const;
62 // Raw access to the pixbuf. May be NULL. Used for a few gdk operations
63 // regarding window shaping.
64 GdkPixbuf* pixbuf() { return pixbuf_; }
67 typedef std::vector<std::pair<GdkDisplay*, cairo_surface_t*> > SurfaceVector;
69 // Returns a surface . Caches results so only one copy of the image data
70 // lives on the display server.
71 cairo_surface_t* GetSurfaceFor(cairo_t* cr, GdkDisplay* display) const;
76 // Our list of cached surfaces. 99% of the time, this will only contain a
77 // single entry. At most two. We need to get this right for multiple displays
78 // to work correct, since each GdkDisplay is a different display server.
79 mutable SurfaceVector surface_map_;
84 #endif // UI_GFX_IMAGE_CAIRO_CACHED_SURFACE_H_