diff -r 000000000000 -r 6474c204b198 gfx/thebes/gfxQtNativeRenderer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/thebes/gfxQtNativeRenderer.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef GFXQTNATIVERENDER_H_
+#define GFXQTNATIVERENDER_H_
+
+#include "gfxColor.h"
+#include "gfxContext.h"
+#include "gfxXlibSurface.h"
+
+class QRect;
+struct nsIntRect;
+
+/**
+ * This class lets us take code that draws into an Xlib surface drawable and lets us
+ * use it to draw into any Thebes context. The user should subclass this class,
+ * override NativeDraw, and then call Draw(). The drawing will be subjected
+ * to all Thebes transformations, clipping etc.
+ */
+class gfxQtNativeRenderer {
+public:
+    /**
+     * Perform the native drawing.
+     * @param offsetX draw at this offset into the given drawable
+     * @param offsetY draw at this offset into the given drawable
+     * @param clipRects an array of rects; clip to the union
+     * @param numClipRects the number of rects in the array, or zero if
+     * no clipping is required
+     */
+    virtual nsresult DrawWithXlib(cairo_surface_t* surface,
+                                  nsIntPoint offset,
+                                  nsIntRect* clipRects, uint32_t numClipRects) = 0;
+  
+    enum {
+        // If set, then Draw() is opaque, i.e., every pixel in the intersection
+        // of the clipRect and (offset.x,offset.y,bounds.width,bounds.height)
+        // will be set and there is no dependence on what the existing pixels
+        // in the drawable are set to.
+        DRAW_IS_OPAQUE = 0x01,
+        // If set, then numClipRects can be zero or one
+        DRAW_SUPPORTS_CLIP_RECT = 0x04,
+        // If set, then numClipRects can be any value. If neither this
+        // nor CLIP_RECT are set, then numClipRects will be zero
+        DRAW_SUPPORTS_CLIP_LIST = 0x08,
+        // If set, then the visual passed in can be any visual, otherwise the
+        // visual passed in must be the default visual for dpy's default screen
+        DRAW_SUPPORTS_ALTERNATE_VISUAL = 0x10,
+        // If set, then the Screen 'screen' in the callback can be different
+        // from the default Screen of the display passed to 'Draw' and can be
+        // on a different display.
+        DRAW_SUPPORTS_ALTERNATE_SCREEN = 0x20
+    };
+
+    /**
+     * @param flags see above
+     * @param size Draw()'s drawing is guaranteed to be restricted to
+     * the rectangle (offset.x,offset.y,size.width,size.height)
+     * @param dpy a display to use for the drawing if ctx doesn't have one
+     * @param resultSurface if non-null, we will try to capture a copy of the
+     * rendered image into a surface similar to the surface of ctx; if
+     * successful, a pointer to the new gfxASurface is stored in *resultSurface,
+     * otherwise *resultSurface is set to nullptr.
+     */
+    nsresult Draw(gfxContext* ctx, nsIntSize size,
+                  uint32_t flags, Screen* screen, Visual* visual);
+};
+
+#endif /*GFXQTNATIVERENDER_H_*/