layout/svg/nsSVGMaskFrame.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 __NS_SVGMASKFRAME_H__
   7 #define __NS_SVGMASKFRAME_H__
   8
   9 #include "mozilla/Attributes.h"
  10 #include "gfxPattern.h"
  11 #include "gfxMatrix.h"
  12 #include "nsSVGContainerFrame.h"
  13 #include "nsSVGUtils.h"
  14
  15 class gfxContext;
  16 class nsRenderingContext;
  17
  18 typedef nsSVGContainerFrame nsSVGMaskFrameBase;
  19
  20 class nsSVGMaskFrame MOZ_FINAL : public nsSVGMaskFrameBase
  21 {
  22   friend nsIFrame*
  23   NS_NewSVGMaskFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
  24 protected:
  25   explicit nsSVGMaskFrame(nsStyleContext* aContext)
  26     : nsSVGMaskFrameBase(aContext)
  27     , mInUse(false)
  28   {
  29     AddStateBits(NS_FRAME_IS_NONDISPLAY);
  30   }
  31
  32 public:
  33   NS_DECL_FRAMEARENA_HELPERS
  34
  35   // nsSVGMaskFrame method:
  36   already_AddRefed<gfxPattern> GetMaskForMaskedFrame(gfxContext* aContext,
  37                                                      nsIFrame* aMaskedFrame,
  38                                                      const gfxMatrix &aMatrix,
  39                                                      float aOpacity);
  40
  41   virtual nsresult AttributeChanged(int32_t         aNameSpaceID,
  42                                     nsIAtom*        aAttribute,
  43                                     int32_t         aModType) MOZ_OVERRIDE;
  44
  45 #ifdef DEBUG
  46   virtual void Init(nsIContent*       aContent,
  47                     nsContainerFrame* aParent,
  48                     nsIFrame*         aPrevInFlow) MOZ_OVERRIDE;
  49 #endif
  50
  51   virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
  52                                 const nsRect&           aDirtyRect,
  53                                 const nsDisplayListSet& aLists) MOZ_OVERRIDE {}
  54
  55   /**
  56    * Get the "type" of the frame
  57    *
  58    * @see nsGkAtoms::svgMaskFrame
  59    */
  60   virtual nsIAtom* GetType() const MOZ_OVERRIDE;
  61
  62 #ifdef DEBUG_FRAME_DUMP
  63   virtual nsresult GetFrameName(nsAString& aResult) const MOZ_OVERRIDE
  64   {
  65     return MakeFrameName(NS_LITERAL_STRING("SVGMask"), aResult);
  66   }
  67 #endif
  68
  69 private:
  70   // A helper class to allow us to paint masks safely. The helper
  71   // automatically sets and clears the mInUse flag on the mask frame
  72   // (to prevent nasty reference loops). It's easy to mess this up
  73   // and break things, so this helper makes the code far more robust.
  74   class MOZ_STACK_CLASS AutoMaskReferencer
  75   {
  76   public:
  77     explicit AutoMaskReferencer(nsSVGMaskFrame *aFrame
  78                                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
  79        : mFrame(aFrame) {
  80       MOZ_GUARD_OBJECT_NOTIFIER_INIT;
  81       NS_ASSERTION(!mFrame->mInUse, "reference loop!");
  82       mFrame->mInUse = true;
  83     }
  84     ~AutoMaskReferencer() {
  85       mFrame->mInUse = false;
  86     }
  87   private:
  88     nsSVGMaskFrame *mFrame;
  89     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
  90   };
  91
  92   nsIFrame *mMaskParent;
  93   nsAutoPtr<gfxMatrix> mMaskParentMatrix;
  94   // recursion prevention flag
  95   bool mInUse;
  96
  97   // nsSVGContainerFrame methods:
  98   virtual gfxMatrix GetCanvasTM(uint32_t aFor,
  99                                 nsIFrame* aTransformRoot = nullptr) MOZ_OVERRIDE;
 100 };
 101
 102 #endif