Add PlatformPictureSkia and RecordingPlatformDeviceSkia.

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_
 
 // The platform-specific device will include the necessary platform headers
 // to get the surface type.
 #include "skia/ext/platform_device.h"
@@ skipping 102 matching lines @@
 // Use this instead of CreateBitmapCanvas in places that are likely to
 // attempt to allocate very large canvases (therefore likely to fail),
 // and where it is possible to recover gracefully from the failed allocation.
 SK_API SkCanvas* TryCreateBitmapCanvas(int width, int height, bool is_opaque);
 
 // Returns true if native platform routines can be used to draw on the
 // given canvas. If this function returns false, BeginPlatformPaint will
 // return NULL PlatformSurface.
 SK_API bool SupportsPlatformPaint(const SkCanvas* canvas);
 
+// Returns true if native platform routines can be used to draw on the
+// given canvas without any indirect rendering taking place.

[alokp, 2012/09/17 16:29:30]

I am not quite clear on the differences between these two functions. May be a
comment about usage would help.

[reed1, 2012/09/17 16:51:24]

+1 -- not sure the diff between these two functions.

[reveman, 2012/09/17 21:22:16]

Sure, does updating the comment to the following make it clear?

// Returns true if native platform routines can be used to draw on the          
// given canvas without any indirect rendering taking place. Indirect           
// rendering can be expensive so it's recommended to avoid using                
// platform paint if possible when direct platform paint isn't supported.       
// E.g. if there's a method to perform text rendering without platform          
// paint then it's likely much more efficient to use that method in the         
// case where this function returns false.

[nduca, 2012/09/18 09:54:24]

Done.

[nduca, 2012/09/18 09:54:24]

Would a better tweak for this be to change SupportsPlatformPaint to be more like
a capabilities query that returns an enum? PlatformPaintIndirect  |
PlatformPaintDirect | Unsupported?

[reveman, 2012/09/18 17:56:15]

I left this as SupportsPlatformPaint/SupportsDirectPlatformPaint in the latest
patch but I'd be fine changing this to:

enum PlatformPaintType {
  PlatformPaintUnsupported = 0,
  PlatformPaintIndirect,
  PlatformPaintDirect
};
PlatformPaintType PlatformPaintSupport();

if that would be preferred?

+SK_API bool SupportsDirectPlatformPaint(const SkCanvas* canvas);
+
 // Draws into the a native platform surface, |context|.  Forwards to
 // DrawToNativeContext on a PlatformDevice instance bound to the top device.
 // If no PlatformDevice instance is bound, is a no-operation.
 SK_API void DrawToNativeContext(SkCanvas* canvas, PlatformSurface context,
                                 int x, int y, const PlatformRect* src_rect);
 
 // Sets the opacity of each pixel in the specified region to be opaque.
 SK_API void MakeOpaque(SkCanvas* canvas, int x, int y, int width, int height);
 
 // These calls should surround calls to platform drawing routines, the
@@ skipping 22 matching lines @@
   PlatformSurface platform_surface_;
 
   // Disallow copy and assign
   ScopedPlatformPaint(const ScopedPlatformPaint&);
   ScopedPlatformPaint& operator=(const ScopedPlatformPaint&);
 };
 
 }  // namespace skia
 
 #endif  // SKIA_EXT_PLATFORM_CANVAS_H_