dom/canvas/CanvasImageCache.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef CANVASIMAGECACHE_H_
   7 #define CANVASIMAGECACHE_H_
   8
   9 #include "mozilla/Maybe.h"
  10 #include "mozilla/RefPtr.h"
  11 #include "mozilla/gfx/Rect.h"
  12 #include "nsSize.h"
  13
  14 namespace mozilla {
  15 namespace dom {
  16 class Element;
  17 class CanvasRenderingContext2D;
  18 }  // namespace dom
  19 namespace gfx {
  20 class DrawTarget;
  21 class SourceSurface;
  22 }  // namespace gfx
  23 }  // namespace mozilla
  24 class imgIContainer;
  25
  26 namespace mozilla {
  27
  28 class CanvasImageCache {
  29   using SourceSurface = mozilla::gfx::SourceSurface;
  30
  31  public:
  32   /**
  33    * Notify that image element aImage was drawn to aContext canvas
  34    * using the first frame of aRequest's image. The data for the surface is
  35    * in aSurface, and the image size is in aSize. aIntrinsicSize is the size
  36    * the surface is intended to be rendered at.
  37    */
  38   static void NotifyDrawImage(dom::Element* aImage,
  39                               dom::CanvasRenderingContext2D* aContext,
  40                               gfx::DrawTarget* aTarget, SourceSurface* aSource,
  41                               const gfx::IntSize& aSize,
  42                               const gfx::IntSize& aIntrinsicSize,
  43                               const Maybe<gfx::IntRect>& aCropRect);
  44
  45   /**
  46    * Notify that aContext is being destroyed.
  47    */
  48   static void NotifyCanvasDestroyed(dom::CanvasRenderingContext2D* aContext);
  49
  50   /**
  51    * Check whether aImage has recently been drawn any canvas. If we return
  52    * a non-null surface, then the same image was recently drawn into a canvas.
  53    */
  54   static SourceSurface* LookupAllCanvas(dom::Element* aImage,
  55                                         gfx::DrawTarget* aTarget);
  56
  57   /**
  58    * Like the top above, but restricts the lookup to only aContext. This is
  59    * required for CORS security.
  60    */
  61   static SourceSurface* LookupCanvas(dom::Element* aImage,
  62                                      dom::CanvasRenderingContext2D* aContext,
  63                                      gfx::DrawTarget* aTarget,
  64                                      gfx::IntSize* aSizeOut,
  65                                      gfx::IntSize* aIntrinsicSizeOut,
  66                                      Maybe<gfx::IntRect>* aCropRectOut);
  67 };
  68
  69 }  // namespace mozilla
  70
  71 #endif /* CANVASIMAGECACHE_H_ */