layout/svg/SVGImageContext.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_SVGCONTEXT_H_
   7 #define MOZILLA_SVGCONTEXT_H_
   8
   9 #include "mozilla/Maybe.h"
  10 #include "SVGPreserveAspectRatio.h"
  11
  12 namespace mozilla {
  13
  14 // SVG image-specific rendering context. For imgIContainer::Draw.
  15 // Used to pass information such as
  16 //  - viewport information from CSS, and
  17 //  - overridden attributes from an SVG <image> element
  18 // to the image's internal SVG document when it's drawn.
  19 class SVGImageContext
  20 {
  21 public:
  22   SVGImageContext()
  23     : mGlobalOpacity(1.0)
  24   { }
  25
  26   SVGImageContext(nsIntSize aViewportSize,
  27                   Maybe<SVGPreserveAspectRatio> aPreserveAspectRatio,
  28                   gfxFloat aOpacity = 1.0)
  29     : mViewportSize(aViewportSize)
  30     , mPreserveAspectRatio(aPreserveAspectRatio)
  31     , mGlobalOpacity(aOpacity)
  32   { }
  33
  34   const nsIntSize& GetViewportSize() const {
  35     return mViewportSize;
  36   }
  37
  38   const Maybe<SVGPreserveAspectRatio>& GetPreserveAspectRatio() const {
  39     return mPreserveAspectRatio;
  40   }
  41
  42   gfxFloat GetGlobalOpacity() const {
  43     return mGlobalOpacity;
  44   }
  45
  46   bool operator==(const SVGImageContext& aOther) const {
  47     return mViewportSize == aOther.mViewportSize &&
  48            mPreserveAspectRatio == aOther.mPreserveAspectRatio &&
  49            mGlobalOpacity == aOther.mGlobalOpacity;
  50   }
  51
  52   bool operator!=(const SVGImageContext& aOther) const {
  53     return !(*this == aOther);
  54   }
  55
  56   uint32_t Hash() const {
  57     return HashGeneric(mViewportSize.width,
  58                        mViewportSize.height,
  59                        mPreserveAspectRatio.map(HashPAR).valueOr(0),
  60                        HashBytes(&mGlobalOpacity, sizeof(gfxFloat)));
  61   }
  62
  63 private:
  64   static uint32_t HashPAR(const SVGPreserveAspectRatio& aPAR) {
  65     return aPAR.Hash();
  66   }
  67
  68   nsIntSize                     mViewportSize;
  69   Maybe<SVGPreserveAspectRatio> mPreserveAspectRatio;
  70   gfxFloat                      mGlobalOpacity;
  71 };
  72
  73 } // namespace mozilla
  74
  75 #endif // MOZILLA_SVGCONTEXT_H_