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