image/ClippedImage.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_ClippedImage_h
   7 #define mozilla_image_ClippedImage_h
   8
   9 #include "ImageWrapper.h"
  10 #include "mozilla/gfx/2D.h"
  11 #include "mozilla/Maybe.h"
  12 #include "mozilla/RefPtr.h"
  13 #include "mozilla/UniquePtr.h"
  14
  15 namespace mozilla {
  16 namespace image {
  17
  18 class ClippedImageCachedSurface;
  19 class DrawSingleTileCallback;
  20
  21 /**
  22  * An Image wrapper that clips an image against a rectangle. Right now only
  23  * absolute coordinates in pixels are supported.
  24  *
  25  * XXX(seth): There a known (performance, not correctness) issue with
  26  * GetImageContainer. See the comments for that method for more information.
  27  */
  28 class ClippedImage : public ImageWrapper {
  29   typedef gfx::SourceSurface SourceSurface;
  30
  31  public:
  32   NS_INLINE_DECL_REFCOUNTING_INHERITED(ClippedImage, ImageWrapper)
  33
  34   NS_IMETHOD GetWidth(int32_t* aWidth) override;
  35   NS_IMETHOD GetHeight(int32_t* aHeight) override;
  36   NS_IMETHOD GetIntrinsicSize(nsSize* aSize) override;
  37   Maybe<AspectRatio> GetIntrinsicRatio() override;
  38   NS_IMETHOD_(already_AddRefed<SourceSurface>)
  39   GetFrame(uint32_t aWhichFrame, uint32_t aFlags) override;
  40   NS_IMETHOD_(already_AddRefed<SourceSurface>)
  41   GetFrameAtSize(const gfx::IntSize& aSize, uint32_t aWhichFrame,
  42                  uint32_t aFlags) override;
  43   NS_IMETHOD_(bool)
  44   IsImageContainerAvailable(layers::LayerManager* aManager,
  45                             uint32_t aFlags) override;
  46   NS_IMETHOD_(already_AddRefed<layers::ImageContainer>)
  47   GetImageContainer(layers::LayerManager* aManager, uint32_t aFlags) override;
  48   NS_IMETHOD_(bool)
  49   IsImageContainerAvailableAtSize(layers::LayerManager* aManager,
  50                                   const gfx::IntSize& aSize,
  51                                   uint32_t aFlags) override;
  52   NS_IMETHOD_(ImgDrawResult)
  53   GetImageContainerAtSize(layers::LayerManager* aManager,
  54                           const gfx::IntSize& aSize,
  55                           const Maybe<SVGImageContext>& aSVGContext,
  56                           uint32_t aFlags,
  57                           layers::ImageContainer** aOutContainer) override;
  58   NS_IMETHOD_(ImgDrawResult)
  59   Draw(gfxContext* aContext, const nsIntSize& aSize, const ImageRegion& aRegion,
  60        uint32_t aWhichFrame, gfx::SamplingFilter aSamplingFilter,
  61        const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags,
  62        float aOpacity) override;
  63   NS_IMETHOD RequestDiscard() override;
  64   NS_IMETHOD_(Orientation) GetOrientation() override;
  65   NS_IMETHOD_(nsIntRect)
  66   GetImageSpaceInvalidationRect(const nsIntRect& aRect) override;
  67   nsIntSize OptimalImageSizeForDest(const gfxSize& aDest, uint32_t aWhichFrame,
  68                                     gfx::SamplingFilter aSamplingFilter,
  69                                     uint32_t aFlags) override;
  70
  71  protected:
  72   ClippedImage(Image* aImage, nsIntRect aClip,
  73                const Maybe<nsSize>& aSVGViewportSize);
  74
  75   virtual ~ClippedImage();
  76
  77  private:
  78   Pair<ImgDrawResult, RefPtr<SourceSurface>> GetFrameInternal(
  79       const nsIntSize& aSize, const Maybe<SVGImageContext>& aSVGContext,
  80       uint32_t aWhichFrame, uint32_t aFlags, float aOpacity);
  81   bool ShouldClip();
  82   ImgDrawResult DrawSingleTile(gfxContext* aContext, const nsIntSize& aSize,
  83                                const ImageRegion& aRegion, uint32_t aWhichFrame,
  84                                gfx::SamplingFilter aSamplingFilter,
  85                                const Maybe<SVGImageContext>& aSVGContext,
  86                                uint32_t aFlags, float aOpacity);
  87
  88   // If we are forced to draw a temporary surface, we cache it here.
  89   UniquePtr<ClippedImageCachedSurface> mCachedSurface;
  90
  91   nsIntRect mClip;                    // The region to clip to.
  92   Maybe<bool> mShouldClip;            // Memoized ShouldClip() if present.
  93   Maybe<nsIntSize> mSVGViewportSize;  // If we're clipping a VectorImage, this
  94                                       // is the size of viewport of that image.
  95   friend class DrawSingleTileCallback;
  96   friend class ImageOps;
  97 };
  98
  99 }  // namespace image
 100 }  // namespace mozilla
 101
 102 #endif  // mozilla_image_ClippedImage_h