content/browser/renderer_host/backing_store_mac.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_MAC_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_MAC_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/mac/scoped_cftyperef.h"
  10 #include "content/browser/renderer_host/backing_store.h"
  11
  12 namespace content {
  13
  14 class BackingStoreMac : public BackingStore {
  15  public:
  16   // |size| is in view units, |device_scale_factor| is the backingScaleFactor.
  17   // The pixel size of the backing store is size.Scale(device_scale_factor).
  18   BackingStoreMac(RenderWidgetHost* widget,
  19                   const gfx::Size& size,
  20                   float device_scale_factor);
  21   virtual ~BackingStoreMac();
  22
  23   // A CGLayer that stores the contents of the backing store, cached in GPU
  24   // memory if possible.
  25   CGLayerRef cg_layer() { return cg_layer_; }
  26
  27   // A CGBitmapContext that stores the contents of the backing store if the
  28   // corresponding Cocoa view has not been inserted into an NSWindow yet.
  29   CGContextRef cg_bitmap() { return cg_bitmap_; }
  30
  31   // Called when the view's backing scale factor changes.
  32   void ScaleFactorChanged(float device_scale_factor);
  33
  34   // BackingStore implementation.
  35   virtual size_t MemorySize() OVERRIDE;
  36   virtual void PaintToBackingStore(
  37       RenderProcessHost* process,
  38       TransportDIB::Id bitmap,
  39       const gfx::Rect& bitmap_rect,
  40       const std::vector<gfx::Rect>& copy_rects,
  41       float scale_factor,
  42       const base::Closure& completion_callback,
  43       bool* scheduled_completion_callback) OVERRIDE;
  44   virtual bool CopyFromBackingStore(const gfx::Rect& rect,
  45                                     skia::PlatformBitmap* output) OVERRIDE;
  46   virtual void ScrollBackingStore(const gfx::Vector2d& delta,
  47                                   const gfx::Rect& clip_rect,
  48                                   const gfx::Size& view_size) OVERRIDE;
  49
  50   void CopyFromBackingStoreToCGContext(const CGRect& dest_rect,
  51                                        CGContextRef context);
  52
  53  private:
  54   // Creates a CGLayer associated with its owner view's window's graphics
  55   // context, sized properly for the backing store.  Returns NULL if the owner
  56   // is not in a window with a CGContext.  cg_layer_ is assigned this method's
  57   // result.
  58   CGLayerRef CreateCGLayer();
  59
  60   // Creates a CGBitmapContext sized properly for the backing store.  The
  61   // owner view need not be in a window.  cg_bitmap_ is assigned this method's
  62   // result.
  63   CGContextRef CreateCGBitmapContext();
  64
  65   base::ScopedCFTypeRef<CGContextRef> cg_bitmap_;
  66   base::ScopedCFTypeRef<CGLayerRef> cg_layer_;
  67
  68   // Number of physical pixels per view unit. This is 1 or 2 in practice.
  69   float device_scale_factor_;
  70
  71   DISALLOW_COPY_AND_ASSIGN(BackingStoreMac);
  72 };
  73
  74 }  // namespace content
  75
  76 #endif  // CONTENT_BROWSER_RENDERER_HOST_BACKING_STORE_MAC_H_