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diff --git a/base/gfx/platform_device_win.h b/base/gfx/platform_device_win.h
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+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef BASE_GFX_PLATFORM_DEVICE_WIN_H__
+#define BASE_GFX_PLATFORM_DEVICE_WIN_H__
+
+#include <vector>
+
+#include "SkDevice.h"
+
+class SkMatrix;
+class SkPath;
+class SkRegion;
+
+namespace gfx {
+
+// 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
+// interface to implement it either with or without a bitmap backend.
+class PlatformDeviceWin : public SkDevice {
+ public:
+  // 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 HDC getBitmapDC() = 0;
+
+  // Draws to the given screen DC, if the bitmap DC doesn't exist, this will
+  // temporarily create it. However, if you have created the bitmap DC, it will
+  // be more efficient if you don't free it until after this call so it doesn't
+  // have to be created twice.  If src_rect is null, then the entirety of the
+  // source device will be copied.
+  virtual void drawToHDC(HDC dc, int x, int y, const RECT* src_rect) = 0;
+
+  // Invoke before using GDI functions. See description in platform_device.cc
+  // for specifics.
+  // NOTE: x,y,width and height are relative to the current transform.
+  virtual void prepareForGDI(int x, int y, int width, int height) { }
+
+  // Invoke after using GDI functions. See description in platform_device.cc
+  // for specifics.
+  // NOTE: x,y,width and height are relative to the current transform.
+  virtual void postProcessGDI(int x, int y, int width, int height) { }
+
+  // Sets the opacity of each pixel in the specified region to be opaque.
+  virtual void makeOpaque(int x, int y, int width, int height) { }
+
+  // Call this function to fix the alpha channels before compositing this layer
+  // onto another. Internally, the device uses a special alpha method to work
+  // around problems with Windows. This call will put the values into what
+  // Skia expects, so it can be composited onto other layers.
+  //
+  // After this call, no more drawing can be done because the
+  // alpha channels will be "correct", which, if this function is called again
+  // will make them wrong. See the implementation for more discussion.
+  virtual void fixupAlphaBeforeCompositing() { }
+
+  // Returns if the preferred rendering engine is vectorial or bitmap based.
+  virtual bool IsVectorial() = 0;
+
+  // Initializes the default settings and colors in a device context.
+  static void InitializeDC(HDC context);
+
+  // Loads a SkPath into the GDI context. The path can there after be used for
+  // clipping or as a stroke.
+  static void 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.
+  PlatformDeviceWin(const SkBitmap& bitmap);
+
+  // 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);
+};
+
+}  // namespace gfx
+
+#endif  // BASE_GFX_PLATFORM_DEVICE_WIN_H__