layout/svg/nsSVGFilterFrame.cpp

   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 // Main header first:
   7 #include "nsSVGFilterFrame.h"
   8
   9 // Keep others in (case-insensitive) order:
  10 #include "gfxUtils.h"
  11 #include "nsGkAtoms.h"
  12 #include "nsRenderingContext.h"
  13 #include "nsSVGEffects.h"
  14 #include "nsSVGElement.h"
  15 #include "mozilla/dom/SVGFilterElement.h"
  16 #include "nsSVGFilterInstance.h"
  17 #include "nsSVGIntegrationUtils.h"
  18 #include "nsSVGUtils.h"
  19 #include "nsContentUtils.h"
  20
  21 using namespace mozilla::dom;
  22
  23 nsIFrame*
  24 NS_NewSVGFilterFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
  25 {
  26   return new (aPresShell) nsSVGFilterFrame(aContext);
  27 }
  28
  29 NS_IMPL_FRAMEARENA_HELPERS(nsSVGFilterFrame)
  30
  31 class MOZ_STACK_CLASS nsSVGFilterFrame::AutoFilterReferencer
  32 {
  33 public:
  34   explicit AutoFilterReferencer(nsSVGFilterFrame *aFrame MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
  35     : mFrame(aFrame)
  36   {
  37     MOZ_GUARD_OBJECT_NOTIFIER_INIT;
  38     // Reference loops should normally be detected in advance and handled, so
  39     // we're not expecting to encounter them here
  40     NS_ABORT_IF_FALSE(!mFrame->mLoopFlag, "Undetected reference loop!");
  41     mFrame->mLoopFlag = true;
  42   }
  43   ~AutoFilterReferencer() {
  44     mFrame->mLoopFlag = false;
  45   }
  46 private:
  47   nsSVGFilterFrame *mFrame;
  48   MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
  49 };
  50
  51 uint16_t
  52 nsSVGFilterFrame::GetEnumValue(uint32_t aIndex, nsIContent *aDefault)
  53 {
  54   nsSVGEnum& thisEnum =
  55     static_cast<SVGFilterElement *>(mContent)->mEnumAttributes[aIndex];
  56
  57   if (thisEnum.IsExplicitlySet())
  58     return thisEnum.GetAnimValue();
  59
  60   AutoFilterReferencer filterRef(this);
  61
  62   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
  63   return next ? next->GetEnumValue(aIndex, aDefault) :
  64     static_cast<SVGFilterElement *>(aDefault)->
  65       mEnumAttributes[aIndex].GetAnimValue();
  66 }
  67
  68 const nsSVGLength2 *
  69 nsSVGFilterFrame::GetLengthValue(uint32_t aIndex, nsIContent *aDefault)
  70 {
  71   const nsSVGLength2 *thisLength =
  72     &static_cast<SVGFilterElement *>(mContent)->mLengthAttributes[aIndex];
  73
  74   if (thisLength->IsExplicitlySet())
  75     return thisLength;
  76
  77   AutoFilterReferencer filterRef(this);
  78
  79   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
  80   return next ? next->GetLengthValue(aIndex, aDefault) :
  81     &static_cast<SVGFilterElement *>(aDefault)->mLengthAttributes[aIndex];
  82 }
  83
  84 const SVGFilterElement *
  85 nsSVGFilterFrame::GetFilterContent(nsIContent *aDefault)
  86 {
  87   for (nsIContent* child = mContent->GetFirstChild();
  88        child;
  89        child = child->GetNextSibling()) {
  90     nsRefPtr<nsSVGFE> primitive;
  91     CallQueryInterface(child, (nsSVGFE**)getter_AddRefs(primitive));
  92     if (primitive) {
  93       return static_cast<SVGFilterElement *>(mContent);
  94     }
  95   }
  96
  97   AutoFilterReferencer filterRef(this);
  98
  99   nsSVGFilterFrame *next = GetReferencedFilterIfNotInUse();
 100   return next ? next->GetFilterContent(aDefault) :
 101     static_cast<SVGFilterElement *>(aDefault);
 102 }
 103
 104 nsSVGFilterFrame *
 105 nsSVGFilterFrame::GetReferencedFilter()
 106 {
 107   if (mNoHRefURI)
 108     return nullptr;
 109
 110   nsSVGPaintingProperty *property = static_cast<nsSVGPaintingProperty*>
 111     (Properties().Get(nsSVGEffects::HrefProperty()));
 112
 113   if (!property) {
 114     // Fetch our Filter element's xlink:href attribute
 115     SVGFilterElement *filter = static_cast<SVGFilterElement *>(mContent);
 116     nsAutoString href;
 117     filter->mStringAttributes[SVGFilterElement::HREF].GetAnimValue(href, filter);
 118     if (href.IsEmpty()) {
 119       mNoHRefURI = true;
 120       return nullptr; // no URL
 121     }
 122
 123     // Convert href to an nsIURI
 124     nsCOMPtr<nsIURI> targetURI;
 125     nsCOMPtr<nsIURI> base = mContent->GetBaseURI();
 126     nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(targetURI), href,
 127                                               mContent->GetCurrentDoc(), base);
 128
 129     property =
 130       nsSVGEffects::GetPaintingProperty(targetURI, this, nsSVGEffects::HrefProperty());
 131     if (!property)
 132       return nullptr;
 133   }
 134
 135   nsIFrame *result = property->GetReferencedFrame();
 136   if (!result)
 137     return nullptr;
 138
 139   nsIAtom* frameType = result->GetType();
 140   if (frameType != nsGkAtoms::svgFilterFrame)
 141     return nullptr;
 142
 143   return static_cast<nsSVGFilterFrame*>(result);
 144 }
 145
 146 nsSVGFilterFrame *
 147 nsSVGFilterFrame::GetReferencedFilterIfNotInUse()
 148 {
 149   nsSVGFilterFrame *referenced = GetReferencedFilter();
 150   if (!referenced)
 151     return nullptr;
 152
 153   if (referenced->mLoopFlag) {
 154     // XXXjwatt: we should really send an error to the JavaScript Console here:
 155     NS_WARNING("Filter reference loop detected while inheriting attribute!");
 156     return nullptr;
 157   }
 158
 159   return referenced;
 160 }
 161
 162 nsresult
 163 nsSVGFilterFrame::AttributeChanged(int32_t  aNameSpaceID,
 164                                    nsIAtom* aAttribute,
 165                                    int32_t  aModType)
 166 {
 167   if (aNameSpaceID == kNameSpaceID_None &&
 168       (aAttribute == nsGkAtoms::x ||
 169        aAttribute == nsGkAtoms::y ||
 170        aAttribute == nsGkAtoms::width ||
 171        aAttribute == nsGkAtoms::height ||
 172        aAttribute == nsGkAtoms::filterUnits ||
 173        aAttribute == nsGkAtoms::primitiveUnits)) {
 174     nsSVGEffects::InvalidateDirectRenderingObservers(this);
 175   } else if (aNameSpaceID == kNameSpaceID_XLink &&
 176              aAttribute == nsGkAtoms::href) {
 177     // Blow away our reference, if any
 178     Properties().Delete(nsSVGEffects::HrefProperty());
 179     mNoHRefURI = false;
 180     // And update whoever references us
 181     nsSVGEffects::InvalidateDirectRenderingObservers(this);
 182   }
 183   return nsSVGFilterFrameBase::AttributeChanged(aNameSpaceID,
 184                                                 aAttribute, aModType);
 185 }
 186
 187 #ifdef DEBUG
 188 void
 189 nsSVGFilterFrame::Init(nsIContent*       aContent,
 190                        nsContainerFrame* aParent,
 191                        nsIFrame*         aPrevInFlow)
 192 {
 193   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::filter),
 194                "Content is not an SVG filter");
 195
 196   nsSVGFilterFrameBase::Init(aContent, aParent, aPrevInFlow);
 197 }
 198 #endif /* DEBUG */
 199
 200 nsIAtom *
 201 nsSVGFilterFrame::GetType() const
 202 {
 203   return nsGkAtoms::svgFilterFrame;
 204 }