image/FrozenImage.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 mozilla_image_FrozenImage_h
   7 #define mozilla_image_FrozenImage_h
   8
   9 #include "ImageWrapper.h"
  10 #include "mozilla/gfx/2D.h"
  11 #include "mozilla/RefPtr.h"
  12
  13 namespace mozilla {
  14 namespace image {
  15
  16 /**
  17  * An Image wrapper that disables animation, freezing the image at its first
  18  * frame. It does this using two strategies. If this is the only instance of the
  19  * image, animation will never start, because IncrementAnimationConsumers is
  20  * ignored. If there is another instance that is animated, that's still OK,
  21  * because any imgIContainer method that is affected by animation gets its
  22  * aWhichFrame argument set to FRAME_FIRST when it passes through FrozenImage.
  23  *
  24  * XXX(seth): There a known (performance, not correctness) issue with
  25  * GetImageContainer. See the comments for that method for more information.
  26  */
  27 class FrozenImage : public ImageWrapper {
  28   typedef gfx::SourceSurface SourceSurface;
  29
  30  public:
  31   NS_INLINE_DECL_REFCOUNTING_INHERITED(FrozenImage, ImageWrapper)
  32
  33   virtual void IncrementAnimationConsumers() override;
  34   virtual void DecrementAnimationConsumers() override;
  35
  36   NS_IMETHOD GetAnimated(bool* aAnimated) override;
  37   NS_IMETHOD_(already_AddRefed<SourceSurface>)
  38   GetFrame(uint32_t aWhichFrame, uint32_t aFlags) override;
  39   NS_IMETHOD_(already_AddRefed<SourceSurface>)
  40   GetFrameAtSize(const gfx::IntSize& aSize, uint32_t aWhichFrame,
  41                  uint32_t aFlags) override;
  42   NS_IMETHOD_(bool)
  43   IsImageContainerAvailable(layers::LayerManager* aManager,
  44                             uint32_t aFlags) override;
  45   NS_IMETHOD_(already_AddRefed<layers::ImageContainer>)
  46   GetImageContainer(layers::LayerManager* aManager, uint32_t aFlags) override;
  47   NS_IMETHOD_(bool)
  48   IsImageContainerAvailableAtSize(layers::LayerManager* aManager,
  49                                   const gfx::IntSize& aSize,
  50                                   uint32_t aFlags) override;
  51   NS_IMETHOD_(ImgDrawResult)
  52   GetImageContainerAtSize(layers::LayerManager* aManager,
  53                           const gfx::IntSize& aSize,
  54                           const Maybe<SVGImageContext>& aSVGContext,
  55                           uint32_t aFlags,
  56                           layers::ImageContainer** aOutContainer) override;
  57   NS_IMETHOD_(ImgDrawResult)
  58   Draw(gfxContext* aContext, const nsIntSize& aSize, const ImageRegion& aRegion,
  59        uint32_t aWhichFrame, gfx::SamplingFilter aSamplingFilter,
  60        const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags,
  61        float aOpacity) override;
  62   NS_IMETHOD StartDecoding(uint32_t aFlags, uint32_t aWhichFrame) override;
  63   NS_IMETHOD_(bool)
  64   StartDecodingWithResult(uint32_t aFlags, uint32_t aWhichFrame) override;
  65   NS_IMETHOD_(DecodeResult)
  66   RequestDecodeWithResult(uint32_t aFlags, uint32_t aWhichFrame) override;
  67   NS_IMETHOD RequestDecodeForSize(const nsIntSize& aSize, uint32_t aFlags,
  68                                   uint32_t aWhichFrame) override;
  69   NS_IMETHOD_(void) RequestRefresh(const TimeStamp& aTime) override;
  70   NS_IMETHOD GetAnimationMode(uint16_t* aAnimationMode) override;
  71   NS_IMETHOD SetAnimationMode(uint16_t aAnimationMode) override;
  72   NS_IMETHOD ResetAnimation() override;
  73   NS_IMETHOD_(float) GetFrameIndex(uint32_t aWhichFrame) override;
  74
  75  protected:
  76   explicit FrozenImage(Image* aImage) : ImageWrapper(aImage) {}
  77   virtual ~FrozenImage() {}
  78
  79  private:
  80   friend class ImageOps;
  81 };
  82
  83 }  // namespace image
  84 }  // namespace mozilla
  85
  86 #endif  // mozilla_image_FrozenImage_h