Eliminate skia::PlatformCanvas - Step 1

skia/ext/platform_canvas.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SKIA_EXT_PLATFORM_CANVAS_H_
 #define SKIA_EXT_PLATFORM_CANVAS_H_
 #pragma once
 
 // The platform-specific device will include the necessary platform headers
 // to get the surface type.
@@ skipping 96 matching lines @@
   // Calling SkCanvas' version will create a new device which is not compatible
   // with us and we will crash if somebody tries to draw into it with
   // CoreGraphics.
   virtual SkDevice* setBitmapDevice(const SkBitmap& bitmap);
 
   // Disallow copy and assign.
   PlatformCanvas(const PlatformCanvas&);
   PlatformCanvas& operator=(const PlatformCanvas&);
 };
 
+// Creates a canvas with raster bitmap backing.
+// Set is_opaque if you are going to erase the bitmap and not use
+// transparency: this will enable some optimizations.
+SK_API SkCanvas* CreateBitmapCanvas(int width, int height, bool is_opaque);

[gwright, 2011/04/07 15:28:12]

Do we want an is_offscreen parameter here as well?

[alokp, 2011/04/07 15:57:36]

May be. The one I am replacing in webkit does not need it. I will revisit it
once I have replaced all create instances with a factory.

+
+// These calls should surround calls to platform drawing routines, the
+// surface returned here can be used with the native platform routines.
+//
+// Call EndPlatformPaint when you are done and want to use skia operations
+// after calling the platform-specific BeginPlatformPaint; this will
+// synchronize the bitmap to OS if necessary.
+//
+// Note: These functions will eventually replace
+// PlatformCanvas::beginPlatformPaint and PlatformCanvas::endPlatformPaint.
+SK_API PlatformDevice::PlatformSurface BeginPlatformPaint(SkCanvas* canvas);
+SK_API void EndPlatformPaint(SkCanvas* canvas);
+
 }  // namespace skia
 
 #endif  // SKIA_EXT_PLATFORM_CANVAS_H_