Provide what looks like the minimal platform specific interface for skia. This will undoubtedly grow in the future.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@1513 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 53 insertions, 0 deletions

diff --git a/base/gfx/platform_canvas_linux.h b/base/gfx/platform_canvas_linux.h
new file mode 100644
index 0000000..4030a55
--- /dev/null
+++ b/base/gfx/platform_canvas_linux.h
@@ -0,0 +1,53 @@
+// Copyright (c) 2006-2008 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 BASE_GFX_PLATFORM_CANVAS_LINUX_H_
+#define BASE_GFX_PLATFORM_CANVAS_LINUX_H_
+
+#include "base/gfx/platform_device_linux.h"
+#include "base/basictypes.h"
+
+#import "SkCanvas.h"
+
+namespace gfx {
+
+// This class is a specialization of the regular SkCanvas that is designed to
+// work with a gfx::PlatformDevice to manage platform-specific drawing. It
+// allows using both Skia operations and platform-specific operations.
+class PlatformCanvasLinux : public SkCanvas {
+ public:
+  // Set is_opaque if you are going to erase the bitmap and not use
+  // tranparency: this will enable some optimizations.  The shared_section
+  // parameter is passed to gfx::PlatformDevice::create.  See it for details.
+  //
+  // If you use the version with no arguments, you MUST call initialize()
+  PlatformCanvasLinux();
+  PlatformCanvasLinux(int width, int height, bool is_opaque);
+  virtual ~PlatformCanvasLinux();
+
+  // For two-part init, call if you use the no-argument constructor above
+  void initialize(int width, int height, bool is_opaque);
+
+  // Returns the platform device pointer of the topmost rect with a non-empty
+  // clip. Both the windows and mac versions have an equivalent of this method;
+  // a Linux version is added for compatibility.
+  PlatformDeviceLinux& getTopPlatformDevice() const;
+
+ protected:
+  // Creates a device store for use by the canvas. We override this so that
+  // the device is always our own so we know that we can use GDI operations
+  // on it. Simply calls into createPlatformDevice().
+  virtual SkDevice* createDevice(SkBitmap::Config, int width, int height,
+                                 bool is_opaque);
+
+  // Creates a device store for use by the canvas. By default, it creates a
+  // BitmapPlatformDevice object. Can be overridden to change the object type.
+  virtual SkDevice* createPlatformDevice(int width, int height, bool is_opaque);
+
+  DISALLOW_COPY_AND_ASSIGN(PlatformCanvasLinux);
+};
+
+}  // namespace gfx
+
+#endif  // BASE_GFX_PLATFORM_CANVAS_MAC_H_