dom/svg/SVGAnimatedNumberList.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "SVGAnimatedNumberList.h"
   8
   9 #include <utility>
  10
  11 #include "DOMSVGAnimatedNumberList.h"
  12 #include "SVGNumberListSMILType.h"
  13 #include "mozilla/SMILValue.h"
  14 #include "mozilla/Try.h"
  15 #include "mozilla/dom/SVGElement.h"
  16
  17 using namespace mozilla::dom;
  18
  19 namespace mozilla {
  20
  21 nsresult SVGAnimatedNumberList::SetBaseValueString(const nsAString& aValue) {
  22   SVGNumberList newBaseValue;
  23   MOZ_TRY(newBaseValue.SetValueFromString(aValue));
  24
  25   DOMSVGAnimatedNumberList* domWrapper =
  26       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  27   if (domWrapper) {
  28     // We must send this notification *before* changing mBaseVal! If the length
  29     // of our baseVal is being reduced, our baseVal's DOM wrapper list may have
  30     // to remove DOM items from itself, and any removed DOM items need to copy
  31     // their internal counterpart values *before* we change them.
  32     //
  33     domWrapper->InternalBaseValListWillChangeTo(newBaseValue);
  34   }
  35
  36   // We don't need to call DidChange* here - we're only called by
  37   // SVGElement::ParseAttribute under Element::SetAttr,
  38   // which takes care of notifying.
  39
  40   mIsBaseSet = true;
  41   mBaseVal.SwapWith(newBaseValue);
  42   return NS_OK;
  43 }
  44
  45 void SVGAnimatedNumberList::ClearBaseValue(uint32_t aAttrEnum) {
  46   DOMSVGAnimatedNumberList* domWrapper =
  47       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  48   if (domWrapper) {
  49     // We must send this notification *before* changing mBaseVal! (See above.)
  50     domWrapper->InternalBaseValListWillChangeTo(SVGNumberList());
  51   }
  52   mBaseVal.Clear();
  53   mIsBaseSet = false;
  54   // Caller notifies
  55 }
  56
  57 nsresult SVGAnimatedNumberList::SetAnimValue(const SVGNumberList& aNewAnimValue,
  58                                              SVGElement* aElement,
  59                                              uint32_t aAttrEnum) {
  60   DOMSVGAnimatedNumberList* domWrapper =
  61       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  62   if (domWrapper) {
  63     // A new animation may totally change the number of items in the animVal
  64     // list, replacing what was essentially a mirror of the baseVal list, or
  65     // else replacing and overriding an existing animation. When this happens
  66     // we must try and keep our animVal's DOM wrapper in sync (see the comment
  67     // in DOMSVGAnimatedNumberList::InternalBaseValListWillChangeTo).
  68     //
  69     // It's not possible for us to reliably distinguish between calls to this
  70     // method that are setting a new sample for an existing animation, and
  71     // calls that are setting the first sample of an animation that will
  72     // override an existing animation. Happily it's cheap to just blindly
  73     // notify our animVal's DOM wrapper of its internal counterpart's new value
  74     // each time this method is called, so that's what we do.
  75     //
  76     // Note that we must send this notification *before* setting or changing
  77     // mAnimVal! (See the comment in SetBaseValueString above.)
  78     //
  79     domWrapper->InternalAnimValListWillChangeTo(aNewAnimValue);
  80   }
  81   if (!mAnimVal) {
  82     mAnimVal = MakeUnique<SVGNumberList>();
  83   }
  84   nsresult rv = mAnimVal->CopyFrom(aNewAnimValue);
  85   if (NS_FAILED(rv)) {
  86     // OOM. We clear the animation, and, importantly, ClearAnimValue() ensures
  87     // that mAnimVal and its DOM wrapper (if any) will have the same length!
  88     ClearAnimValue(aElement, aAttrEnum);
  89     return rv;
  90   }
  91   aElement->DidAnimateNumberList(aAttrEnum);
  92   return NS_OK;
  93 }
  94
  95 void SVGAnimatedNumberList::ClearAnimValue(SVGElement* aElement,
  96                                            uint32_t aAttrEnum) {
  97   DOMSVGAnimatedNumberList* domWrapper =
  98       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  99   if (domWrapper) {
 100     // When all animation ends, animVal simply mirrors baseVal, which may have
 101     // a different number of items to the last active animated value. We must
 102     // keep the length of our animVal's DOM wrapper list in sync, and again we
 103     // must do that before touching mAnimVal. See comments above.
 104     //
 105     domWrapper->InternalAnimValListWillChangeTo(mBaseVal);
 106   }
 107   mAnimVal = nullptr;
 108   aElement->DidAnimateNumberList(aAttrEnum);
 109 }
 110
 111 UniquePtr<SMILAttr> SVGAnimatedNumberList::ToSMILAttr(SVGElement* aSVGElement,
 112                                                       uint8_t aAttrEnum) {
 113   return MakeUnique<SMILAnimatedNumberList>(this, aSVGElement, aAttrEnum);
 114 }
 115
 116 nsresult SVGAnimatedNumberList::SMILAnimatedNumberList::ValueFromString(
 117     const nsAString& aStr, const dom::SVGAnimationElement* /*aSrcElement*/,
 118     SMILValue& aValue, bool& aPreventCachingOfSandwich) const {
 119   SMILValue val(&SVGNumberListSMILType::sSingleton);
 120   SVGNumberListAndInfo* nlai = static_cast<SVGNumberListAndInfo*>(val.mU.mPtr);
 121   nsresult rv = nlai->SetValueFromString(aStr);
 122   if (NS_SUCCEEDED(rv)) {
 123     nlai->SetInfo(mElement);
 124     aValue = std::move(val);
 125   }
 126   return rv;
 127 }
 128
 129 SMILValue SVGAnimatedNumberList::SMILAnimatedNumberList::GetBaseValue() const {
 130   // To benefit from Return Value Optimization and avoid copy constructor calls
 131   // due to our use of return-by-value, we must return the exact same object
 132   // from ALL return points. This function must only return THIS variable:
 133   SMILValue val;
 134
 135   SMILValue tmp(&SVGNumberListSMILType::sSingleton);
 136   SVGNumberListAndInfo* nlai = static_cast<SVGNumberListAndInfo*>(tmp.mU.mPtr);
 137   nsresult rv = nlai->CopyFrom(mVal->mBaseVal);
 138   if (NS_SUCCEEDED(rv)) {
 139     nlai->SetInfo(mElement);
 140     std::swap(val, tmp);
 141   }
 142   return val;
 143 }
 144
 145 nsresult SVGAnimatedNumberList::SMILAnimatedNumberList::SetAnimValue(
 146     const SMILValue& aValue) {
 147   NS_ASSERTION(aValue.mType == &SVGNumberListSMILType::sSingleton,
 148                "Unexpected type to assign animated value");
 149   if (aValue.mType == &SVGNumberListSMILType::sSingleton) {
 150     mVal->SetAnimValue(*static_cast<SVGNumberListAndInfo*>(aValue.mU.mPtr),
 151                        mElement, mAttrEnum);
 152   }
 153   return NS_OK;
 154 }
 155
 156 void SVGAnimatedNumberList::SMILAnimatedNumberList::ClearAnimValue() {
 157   if (mVal->mAnimVal) {
 158     mVal->ClearAnimValue(mElement, mAttrEnum);
 159   }
 160 }
 161
 162 }  // namespace mozilla