author Andrew Osmond <>
Mon, 04 Jun 2018 08:29:50 -0400
changeset 442380 453d21db2a306f4800e8be4d77f6d61000cb9a0c
parent 436249 d10ab3f7b4eafdd78d9e266953b8269a088ed7f0
child 448947 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1465619 - Part 10. Re-add support for discarding animated image frames. r=tnikkel AnimatedFrameDiscardingQueue subclasses AnimationFrameBuffer to allow a cleaner abstraction over the behaviour change when we cross the threshold of too high a memory footprint for an animated image. The next patch will build on top of this to provide an abstraction to reuse the discarded frames. Differential Revision:

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at */

#ifndef mozilla_image_ClippedImage_h
#define mozilla_image_ClippedImage_h

#include "ImageWrapper.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/Maybe.h"
#include "mozilla/RefPtr.h"
#include "mozilla/UniquePtr.h"

namespace mozilla {
namespace image {

class ClippedImageCachedSurface;
class DrawSingleTileCallback;

 * An Image wrapper that clips an image against a rectangle. Right now only
 * absolute coordinates in pixels are supported.
 * XXX(seth): There a known (performance, not correctness) issue with
 * GetImageContainer. See the comments for that method for more information.
class ClippedImage : public ImageWrapper
  typedef gfx::SourceSurface SourceSurface;


  NS_IMETHOD GetWidth(int32_t* aWidth) override;
  NS_IMETHOD GetHeight(int32_t* aHeight) override;
  NS_IMETHOD GetIntrinsicSize(nsSize* aSize) override;
  NS_IMETHOD GetIntrinsicRatio(nsSize* aRatio) override;
    GetFrame(uint32_t aWhichFrame, uint32_t aFlags) override;
    GetFrameAtSize(const gfx::IntSize& aSize,
                   uint32_t aWhichFrame,
                   uint32_t aFlags) override;
  NS_IMETHOD_(bool) IsImageContainerAvailable(layers::LayerManager* aManager,
                                              uint32_t aFlags) override;
    GetImageContainer(layers::LayerManager* aManager,
                      uint32_t aFlags) override;
    IsImageContainerAvailableAtSize(layers::LayerManager* aManager,
                                    const gfx::IntSize& aSize,
                                    uint32_t aFlags) override;
    GetImageContainerAtSize(layers::LayerManager* aManager,
                            const gfx::IntSize& aSize,
                            const Maybe<SVGImageContext>& aSVGContext,
                            uint32_t aFlags,
                            layers::ImageContainer** aOutContainer) override;
  NS_IMETHOD_(ImgDrawResult) Draw(gfxContext* aContext,
                               const nsIntSize& aSize,
                               const ImageRegion& aRegion,
                               uint32_t aWhichFrame,
                               gfx::SamplingFilter aSamplingFilter,
                               const Maybe<SVGImageContext>& aSVGContext,
                               uint32_t aFlags,
                               float aOpacity) override;
  NS_IMETHOD RequestDiscard() override;
  NS_IMETHOD_(Orientation) GetOrientation() override;
  NS_IMETHOD_(nsIntRect) GetImageSpaceInvalidationRect(const nsIntRect& aRect)
  nsIntSize OptimalImageSizeForDest(const gfxSize& aDest,
                                    uint32_t aWhichFrame,
                                    gfx::SamplingFilter aSamplingFilter,
                                    uint32_t aFlags) override;

  ClippedImage(Image* aImage, nsIntRect aClip,
               const Maybe<nsSize>& aSVGViewportSize);

  virtual ~ClippedImage();

  Pair<ImgDrawResult, RefPtr<SourceSurface>>
    GetFrameInternal(const nsIntSize& aSize,
                     const Maybe<SVGImageContext>& aSVGContext,
                     uint32_t aWhichFrame,
                     uint32_t aFlags,
                     float aOpacity);
  bool ShouldClip();
  ImgDrawResult DrawSingleTile(gfxContext* aContext,
                            const nsIntSize& aSize,
                            const ImageRegion& aRegion,
                            uint32_t aWhichFrame,
                            gfx::SamplingFilter aSamplingFilter,
                            const Maybe<SVGImageContext>& aSVGContext,
                            uint32_t aFlags,
                            float aOpacity);

  // If we are forced to draw a temporary surface, we cache it here.
  UniquePtr<ClippedImageCachedSurface> mCachedSurface;

  nsIntRect        mClip;            // The region to clip to.
  Maybe<bool>      mShouldClip;      // Memoized ShouldClip() if present.
  Maybe<nsIntSize> mSVGViewportSize; // If we're clipping a VectorImage, this
                                     // is the size of viewport of that image.
  friend class DrawSingleTileCallback;
  friend class ImageOps;

} // namespace image
} // namespace mozilla

#endif // mozilla_image_ClippedImage_h