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/dom/SVGElement.h"
  15
  16 using namespace mozilla::dom;
  17
  18 namespace mozilla {
  19
  20 nsresult SVGAnimatedNumberList::SetBaseValueString(const nsAString& aValue) {
  21   SVGNumberList newBaseValue;
  22   nsresult rv = newBaseValue.SetValueFromString(aValue);
  23   if (NS_FAILED(rv)) {
  24     return rv;
  25   }
  26
  27   DOMSVGAnimatedNumberList* domWrapper =
  28       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  29   if (domWrapper) {
  30     // We must send this notification *before* changing mBaseVal! If the length
  31     // of our baseVal is being reduced, our baseVal's DOM wrapper list may have
  32     // to remove DOM items from itself, and any removed DOM items need to copy
  33     // their internal counterpart values *before* we change them.
  34     //
  35     domWrapper->InternalBaseValListWillChangeTo(newBaseValue);
  36   }
  37
  38   // We don't need to call DidChange* here - we're only called by
  39   // SVGElement::ParseAttribute under Element::SetAttr,
  40   // which takes care of notifying.
  41
  42   mIsBaseSet = true;
  43   rv = mBaseVal.CopyFrom(newBaseValue);
  44   if (NS_FAILED(rv) && domWrapper) {
  45     // Attempting to increase mBaseVal's length failed - reduce domWrapper
  46     // back to the same length:
  47     domWrapper->InternalBaseValListWillChangeTo(mBaseVal);
  48   }
  49   return rv;
  50 }
  51
  52 void SVGAnimatedNumberList::ClearBaseValue(uint32_t aAttrEnum) {
  53   DOMSVGAnimatedNumberList* domWrapper =
  54       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  55   if (domWrapper) {
  56     // We must send this notification *before* changing mBaseVal! (See above.)
  57     domWrapper->InternalBaseValListWillChangeTo(SVGNumberList());
  58   }
  59   mBaseVal.Clear();
  60   mIsBaseSet = false;
  61   // Caller notifies
  62 }
  63
  64 nsresult SVGAnimatedNumberList::SetAnimValue(const SVGNumberList& aNewAnimValue,
  65                                              SVGElement* aElement,
  66                                              uint32_t aAttrEnum) {
  67   DOMSVGAnimatedNumberList* domWrapper =
  68       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
  69   if (domWrapper) {
  70     // A new animation may totally change the number of items in the animVal
  71     // list, replacing what was essentially a mirror of the baseVal list, or
  72     // else replacing and overriding an existing animation. When this happens
  73     // we must try and keep our animVal's DOM wrapper in sync (see the comment
  74     // in DOMSVGAnimatedNumberList::InternalBaseValListWillChangeTo).
  75     //
  76     // It's not possible for us to reliably distinguish between calls to this
  77     // method that are setting a new sample for an existing animation, and
  78     // calls that are setting the first sample of an animation that will
  79     // override an existing animation. Happily it's cheap to just blindly
  80     // notify our animVal's DOM wrapper of its internal counterpart's new value
  81     // each time this method is called, so that's what we do.
  82     //
  83     // Note that we must send this notification *before* setting or changing
  84     // mAnimVal! (See the comment in SetBaseValueString above.)
  85     //
  86     domWrapper->InternalAnimValListWillChangeTo(aNewAnimValue);
  87   }
  88   if (!mAnimVal) {
  89     mAnimVal = MakeUnique<SVGNumberList>();
  90   }
  91   nsresult rv = mAnimVal->CopyFrom(aNewAnimValue);
  92   if (NS_FAILED(rv)) {
  93     // OOM. We clear the animation, and, importantly, ClearAnimValue() ensures
  94     // that mAnimVal and its DOM wrapper (if any) will have the same length!
  95     ClearAnimValue(aElement, aAttrEnum);
  96     return rv;
  97   }
  98   aElement->DidAnimateNumberList(aAttrEnum);
  99   return NS_OK;
 100 }
 101
 102 void SVGAnimatedNumberList::ClearAnimValue(SVGElement* aElement,
 103                                            uint32_t aAttrEnum) {
 104   DOMSVGAnimatedNumberList* domWrapper =
 105       DOMSVGAnimatedNumberList::GetDOMWrapperIfExists(this);
 106   if (domWrapper) {
 107     // When all animation ends, animVal simply mirrors baseVal, which may have
 108     // a different number of items to the last active animated value. We must
 109     // keep the length of our animVal's DOM wrapper list in sync, and again we
 110     // must do that before touching mAnimVal. See comments above.
 111     //
 112     domWrapper->InternalAnimValListWillChangeTo(mBaseVal);
 113   }
 114   mAnimVal = nullptr;
 115   aElement->DidAnimateNumberList(aAttrEnum);
 116 }
 117
 118 UniquePtr<SMILAttr> SVGAnimatedNumberList::ToSMILAttr(SVGElement* aSVGElement,
 119                                                       uint8_t aAttrEnum) {
 120   return MakeUnique<SMILAnimatedNumberList>(this, aSVGElement, aAttrEnum);
 121 }
 122
 123 nsresult SVGAnimatedNumberList::SMILAnimatedNumberList::ValueFromString(
 124     const nsAString& aStr, const dom::SVGAnimationElement* /*aSrcElement*/,
 125     SMILValue& aValue, bool& aPreventCachingOfSandwich) const {
 126   SMILValue val(&SVGNumberListSMILType::sSingleton);
 127   SVGNumberListAndInfo* nlai = static_cast<SVGNumberListAndInfo*>(val.mU.mPtr);
 128   nsresult rv = nlai->SetValueFromString(aStr);
 129   if (NS_SUCCEEDED(rv)) {
 130     nlai->SetInfo(mElement);
 131     aValue = std::move(val);
 132   }
 133   aPreventCachingOfSandwich = false;
 134   return rv;
 135 }
 136
 137 SMILValue SVGAnimatedNumberList::SMILAnimatedNumberList::GetBaseValue() const {
 138   // To benefit from Return Value Optimization and avoid copy constructor calls
 139   // due to our use of return-by-value, we must return the exact same object
 140   // from ALL return points. This function must only return THIS variable:
 141   SMILValue val;
 142
 143   SMILValue tmp(&SVGNumberListSMILType::sSingleton);
 144   SVGNumberListAndInfo* nlai = static_cast<SVGNumberListAndInfo*>(tmp.mU.mPtr);
 145   nsresult rv = nlai->CopyFrom(mVal->mBaseVal);
 146   if (NS_SUCCEEDED(rv)) {
 147     nlai->SetInfo(mElement);
 148     std::swap(val, tmp);
 149   }
 150   return val;
 151 }
 152
 153 nsresult SVGAnimatedNumberList::SMILAnimatedNumberList::SetAnimValue(
 154     const SMILValue& aValue) {
 155   NS_ASSERTION(aValue.mType == &SVGNumberListSMILType::sSingleton,
 156                "Unexpected type to assign animated value");
 157   if (aValue.mType == &SVGNumberListSMILType::sSingleton) {
 158     mVal->SetAnimValue(*static_cast<SVGNumberListAndInfo*>(aValue.mU.mPtr),
 159                        mElement, mAttrEnum);
 160   }
 161   return NS_OK;
 162 }
 163
 164 void SVGAnimatedNumberList::SMILAnimatedNumberList::ClearAnimValue() {
 165   if (mVal->mAnimVal) {
 166     mVal->ClearAnimValue(mElement, mAttrEnum);
 167   }
 168 }
 169
 170 }  // namespace mozilla