Move HiDPI-related Pepper interfaces to stable

ppapi/cpp/graphics_2d.h

 // Copyright (c) 2012 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 PPAPI_CPP_GRAPHICS_2D_H_
 #define PPAPI_CPP_GRAPHICS_2D_H_
 
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/cpp/resource.h"
 #include "ppapi/cpp/size.h"
@@ skipping 23 matching lines @@
   Graphics2D(const Graphics2D& other);
 
   /// A constructor allocating a new 2D graphics context with the given size
   /// in the browser, resulting object will be is_null() if the allocation
   /// failed.
   ///
   /// @param[in] instance The instance with which this resource will be
   /// associated.
   ///
   /// @param[in] size The size of the 2D graphics context in the browser,
-  /// measured in device pixels.
+  /// measured in pixels. See <code>SetScale()</code> for more information.
   ///
   /// @param[in] is_always_opaque Set the <code>is_always_opaque</code> flag
   /// to true if you know that you will be painting only opaque data to this
   /// context. This option will disable blending when compositing the module
   /// with the web page, which might give higher performance on some computers.
   ///
   /// If you set <code>is_always_opaque</code>, your alpha channel should
   /// always be set to 0xFF or there may be painting artifacts. The alpha values
   /// overwrite the destination alpha values without blending when
   /// <code>is_always_opaque</code> is true.
@@ skipping 12 matching lines @@
   /// of the other 2D graphics context while decrementing the reference counter
   /// of this 2D graphics context.
   ///
   /// @param[in] other An other 2D graphics context.
   ///
   /// @return A new Graphics2D context.
   Graphics2D& operator=(const Graphics2D& other);
 
   /// Getter function for returning size of the 2D graphics context.
   ///
-  /// @return The size of the 2D graphics context measured in device pixels.
+  /// @return The size of the 2D graphics context measured in pixels.
   const Size& size() const { return size_; }
 
   /// PaintImageData() enqueues a paint command of the given image into
   /// the context. This command has no effect until you call Flush(). As a
   /// result, what counts is the contents of the bitmap when you call Flush,
   /// not when you call this function.
   ///
   /// The provided image will be placed at <code>top_left</code> from the top
   /// left of the context's internal backing store. This version of
   /// PaintImageData paints the entire image. Refer to the other version of
@@ skipping 165 matching lines @@
   /// not issued its callback yet.  In the failure case, nothing will be
   /// updated and no callback will be scheduled.
 
   // TODO(darin): We should ensure that the completion callback always runs, so
   // that it is easier for consumers to manage memory referenced by a callback.
 
   // TODO(): Add back in the synchronous mode description once we have support
   // for it.
   int32_t Flush(const CompletionCallback& cc);
 
+  /// SetScale() sets the scale factor that will be applied when painting the
+  /// graphics context onto the output device. Typically, if rendering at device
+  /// resolution is desired, the context would be created with the width and
+  /// height scaled up by the view's GetDeviceScale and SetScale called with a
+  /// scale of 1.0 / GetDeviceScale(). For example, if the view resource passed
+  /// to DidChangeView has a rectangle of (w=200, h=100) and a device scale of
+  /// 2.0, one would call Create with a size of (w=400, h=200) and then call
+  /// SetScale with 0.5. One would then treat each pixel in the context as a
+  /// single device pixel.
+  ///
+  /// @param[in] scale The scale to apply when painting.
+  ///
+  /// @return Returns <code>true</code> on success or <code>false</code>
+  /// if the resource is invalid or the scale factor is 0 or less.
+  bool SetScale(float scale);
+
+  /// GetScale() gets the scale factor that will be applied when painting the
+  /// graphics context onto the output device.
+  ///
+  /// @return Returns the scale factor for the graphics context. If the resource
+  /// is invalid, 0.0 will be returned. The default scale for a graphics context
+  /// is 1.0.
+  float GetScale();
+
  private:
   Size size_;
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_GRAPHICS_2D_H_