CL removing inheritance of SkDevice from PlatformDevice. Flavours of PlatformDevice classes now ...

skia/ext/platform_device_win.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_DEVICE_WIN_H_
 #define SKIA_EXT_PLATFORM_DEVICE_WIN_H_
 #pragma once
 
 #include <windows.h>
 
 #include <vector>
 
 #include "third_party/skia/include/core/SkDevice.h"
 
 class SkMatrix;
 class SkPath;
 class SkRegion;
 
 namespace skia {
 
 // Initializes the default settings and colors in a device context.
 SK_API void InitializeDC(HDC context);
 
-// A device is basically a wrapper around SkBitmap that provides a surface for
-// SkCanvas to draw into. Our device provides a surface Windows can also write
-// to. It also provides functionality to play well with GDI drawing functions.
-// This class is abstract and must be subclassed. It provides the basic
+// A SkDevice is basically a wrapper around SkBitmap that provides a surface for
+// SkCanvas to draw into. PlatformDevice provides a surface Windows can also
+// write to. It also provides functionality to play well with GDI drawing
+// functions. This class is abstract and must be subclassed. It provides the basic
 // interface to implement it either with or without a bitmap backend.
-class SK_API PlatformDevice : public SkDevice {
+//
+// PlatformDevice provides an interface which sub-classes of SkDevice can also
+// provide to allow for drawing by the native platform into the device.
+class SK_API PlatformDevice {
  public:
   typedef HDC PlatformSurface;
 
   // The DC that corresponds to the bitmap, used for GDI operations drawing
   // into the bitmap. This is possibly heavyweight, so it should be existant
   // only during one pass of rendering.
   virtual PlatformSurface BeginPlatformPaint() = 0;
 
   // Finish a previous call to beginPlatformPaint.
   virtual void EndPlatformPaint();
@@ skipping 10 matching lines @@
   virtual void MakeOpaque(int x, int y, int width, int height) { }
 
   // Returns if GDI is allowed to render text to this device.
   virtual bool IsNativeFontRenderingAllowed() { return true; }
 
   // True if AlphaBlend() was called during a
   // BeginPlatformPaint()/EndPlatformPaint() pair.
   // Used by the printing subclasses.  See |VectorPlatformDeviceEmf|.
   virtual bool AlphaBlendUsed() const { return false; }
 
+  // Return the SkDevice instance which is associated with this PlatformDevice.
+  SkDevice* GetOwningDevice() const { return device_; }
+
   // Loads a SkPath into the GDI context. The path can there after be used for
   // clipping or as a stroke. Returns false if the path failed to be loaded.
   static bool LoadPathToDC(HDC context, const SkPath& path);
 
   // Loads a SkRegion into the GDI context.
   static void LoadClippingRegionToDC(HDC context, const SkRegion& region,
                                      const SkMatrix& transformation);
 
  protected:
   // Arrays must be inside structures.
   struct CubicPoints {
     SkPoint p[4];
   };
   typedef std::vector<CubicPoints> CubicPath;
   typedef std::vector<CubicPath> CubicPaths;
 
-  // Forwards |bitmap| to SkDevice's constructor.
-  PlatformDevice(const SkBitmap& bitmap);
+  explicit PlatformDevice(SkDevice* device);
 
   // Loads the specified Skia transform into the device context, excluding
   // perspective (which GDI doesn't support).
   static void LoadTransformToDC(HDC dc, const SkMatrix& matrix);
 
   // Transforms SkPath's paths into a series of cubic path.
   static bool SkPathToCubicPaths(CubicPaths* paths, const SkPath& skpath);
+
+  // The device to which the PlatformDevice interface is bound.
+  SkDevice* device_;
 };
 
 }  // namespace skia
 
 #endif  // SKIA_EXT_PLATFORM_DEVICE_WIN_H_
-