dom/svg/SVGAnimatedTransformList.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 "SVGAnimatedTransformList.h"
   8
   9 #include <utility>
  10
  11 #include "DOMSVGAnimatedTransformList.h"
  12 #include "SVGTransform.h"
  13 #include "SVGTransformListSMILType.h"
  14 #include "mozilla/SMILValue.h"
  15 #include "mozilla/SVGContentUtils.h"
  16 #include "mozilla/dom/MutationEventBinding.h"
  17 #include "mozilla/dom/SVGAnimationElement.h"
  18 #include "nsCharSeparatedTokenizer.h"
  19 #include "nsContentUtils.h"
  20
  21 using namespace mozilla::dom;
  22 using namespace mozilla::dom::SVGTransform_Binding;
  23
  24 namespace mozilla {
  25
  26 nsresult SVGAnimatedTransformList::SetBaseValueString(const nsAString& aValue,
  27                                                       SVGElement* aSVGElement) {
  28   SVGTransformList newBaseValue;
  29   nsresult rv = newBaseValue.SetValueFromString(aValue);
  30   if (NS_FAILED(rv)) {
  31     return rv;
  32   }
  33
  34   return SetBaseValue(newBaseValue, aSVGElement);
  35 }
  36
  37 nsresult SVGAnimatedTransformList::SetBaseValue(const SVGTransformList& aValue,
  38                                                 SVGElement* aSVGElement) {
  39   DOMSVGAnimatedTransformList* domWrapper =
  40       DOMSVGAnimatedTransformList::GetDOMWrapperIfExists(this);
  41   if (domWrapper) {
  42     // We must send this notification *before* changing mBaseVal! If the length
  43     // of our baseVal is being reduced, our baseVal's DOM wrapper list may have
  44     // to remove DOM items from itself, and any removed DOM items need to copy
  45     // their internal counterpart values *before* we change them.
  46     //
  47     domWrapper->InternalBaseValListWillChangeLengthTo(aValue.Length());
  48   }
  49
  50   // (This bool will be copied to our member-var, if attr-change succeeds.)
  51   bool hadTransform = HasTransform();
  52
  53   // We don't need to call DidChange* here - we're only called by
  54   // SVGElement::ParseAttribute under Element::SetAttr,
  55   // which takes care of notifying.
  56
  57   nsresult rv = mBaseVal.CopyFrom(aValue);
  58   if (NS_FAILED(rv) && domWrapper) {
  59     // Attempting to increase mBaseVal's length failed - reduce domWrapper
  60     // back to the same length:
  61     domWrapper->InternalBaseValListWillChangeLengthTo(mBaseVal.Length());
  62   } else {
  63     mIsBaseSet = true;
  64     // We only need to treat this as a creation or removal of a transform if the
  65     // frame already exists and it didn't have an existing one.
  66     mCreatedOrRemovedOnLastChange =
  67         aSVGElement->GetPrimaryFrame() && !hadTransform;
  68   }
  69   return rv;
  70 }
  71
  72 void SVGAnimatedTransformList::ClearBaseValue() {
  73   mCreatedOrRemovedOnLastChange = !HasTransform();
  74
  75   DOMSVGAnimatedTransformList* domWrapper =
  76       DOMSVGAnimatedTransformList::GetDOMWrapperIfExists(this);
  77   if (domWrapper) {
  78     // We must send this notification *before* changing mBaseVal! (See above.)
  79     domWrapper->InternalBaseValListWillChangeLengthTo(0);
  80   }
  81   mBaseVal.Clear();
  82   mIsBaseSet = false;
  83   // Caller notifies
  84 }
  85
  86 nsresult SVGAnimatedTransformList::SetAnimValue(const SVGTransformList& aValue,
  87                                                 SVGElement* aElement) {
  88   bool prevSet = HasTransform() || aElement->GetAnimateMotionTransform();
  89   DOMSVGAnimatedTransformList* domWrapper =
  90       DOMSVGAnimatedTransformList::GetDOMWrapperIfExists(this);
  91   if (domWrapper) {
  92     // A new animation may totally change the number of items in the animVal
  93     // list, replacing what was essentially a mirror of the baseVal list, or
  94     // else replacing and overriding an existing animation. When this happens
  95     // we must try and keep our animVal's DOM wrapper in sync (see the comment
  96     // in DOMSVGAnimatedTransformList::InternalBaseValListWillChangeLengthTo).
  97     //
  98     // It's not possible for us to reliably distinguish between calls to this
  99     // method that are setting a new sample for an existing animation, and
 100     // calls that are setting the first sample of an animation that will
 101     // override an existing animation. Happily it's cheap to just blindly
 102     // notify our animVal's DOM wrapper of its internal counterpart's new value
 103     // each time this method is called, so that's what we do.
 104     //
 105     // Note that we must send this notification *before* setting or changing
 106     // mAnimVal! (See the comment in SetBaseValueString above.)
 107     //
 108     domWrapper->InternalAnimValListWillChangeLengthTo(aValue.Length());
 109   }
 110   if (!mAnimVal) {
 111     mAnimVal = MakeUnique<SVGTransformList>();
 112   }
 113   nsresult rv = mAnimVal->CopyFrom(aValue);
 114   if (NS_FAILED(rv)) {
 115     // OOM. We clear the animation, and, importantly, ClearAnimValue() ensures
 116     // that mAnimVal and its DOM wrapper (if any) will have the same length!
 117     ClearAnimValue(aElement);
 118     return rv;
 119   }
 120   int32_t modType;
 121   if (prevSet) {
 122     modType = MutationEvent_Binding::MODIFICATION;
 123   } else {
 124     modType = MutationEvent_Binding::ADDITION;
 125   }
 126   mCreatedOrRemovedOnLastChange = modType == MutationEvent_Binding::ADDITION;
 127   aElement->DidAnimateTransformList(modType);
 128   return NS_OK;
 129 }
 130
 131 void SVGAnimatedTransformList::ClearAnimValue(SVGElement* aElement) {
 132   DOMSVGAnimatedTransformList* domWrapper =
 133       DOMSVGAnimatedTransformList::GetDOMWrapperIfExists(this);
 134   if (domWrapper) {
 135     // When all animation ends, animVal simply mirrors baseVal, which may have
 136     // a different number of items to the last active animated value. We must
 137     // keep the length of our animVal's DOM wrapper list in sync, and again we
 138     // must do that before touching mAnimVal. See comments above.
 139     //
 140     domWrapper->InternalAnimValListWillChangeLengthTo(mBaseVal.Length());
 141   }
 142   mAnimVal = nullptr;
 143   int32_t modType;
 144   if (HasTransform() || aElement->GetAnimateMotionTransform()) {
 145     modType = MutationEvent_Binding::MODIFICATION;
 146   } else {
 147     modType = MutationEvent_Binding::REMOVAL;
 148   }
 149   mCreatedOrRemovedOnLastChange = modType == MutationEvent_Binding::REMOVAL;
 150   aElement->DidAnimateTransformList(modType);
 151 }
 152
 153 bool SVGAnimatedTransformList::IsExplicitlySet() const {
 154   // Like other methods of this name, we need to know when a transform value has
 155   // been explicitly set.
 156   //
 157   // There are three ways an animated list can become set:
 158   // 1) Markup -- we set mIsBaseSet to true on any successful call to
 159   //    SetBaseValueString and clear it on ClearBaseValue (as called by
 160   //    SVGElement::UnsetAttr or a failed SVGElement::ParseAttribute)
 161   // 2) DOM call -- simply fetching the baseVal doesn't mean the transform value
 162   //    has been set. It is set if that baseVal has one or more transforms in
 163   //    the list.
 164   // 3) Animation -- which will cause the mAnimVal member to be allocated
 165   return mIsBaseSet || !mBaseVal.IsEmpty() || mAnimVal;
 166 }
 167
 168 UniquePtr<SMILAttr> SVGAnimatedTransformList::ToSMILAttr(
 169     SVGElement* aSVGElement) {
 170   return MakeUnique<SMILAnimatedTransformList>(this, aSVGElement);
 171 }
 172
 173 nsresult SVGAnimatedTransformList::SMILAnimatedTransformList::ValueFromString(
 174     const nsAString& aStr, const dom::SVGAnimationElement* aSrcElement,
 175     SMILValue& aValue, bool& aPreventCachingOfSandwich) const {
 176   NS_ENSURE_TRUE(aSrcElement, NS_ERROR_FAILURE);
 177   MOZ_ASSERT(aValue.IsNull(),
 178              "aValue should have been cleared before calling ValueFromString");
 179
 180   const nsAttrValue* typeAttr = aSrcElement->GetParsedAttr(nsGkAtoms::type);
 181   const nsAtom* transformType = nsGkAtoms::translate;  // default val
 182   if (typeAttr) {
 183     if (typeAttr->Type() != nsAttrValue::eAtom) {
 184       // Recognized values of |type| are parsed as an atom -- so if we have
 185       // something other than an atom, then we know already our |type| is
 186       // invalid.
 187       return NS_ERROR_FAILURE;
 188     }
 189     transformType = typeAttr->GetAtomValue();
 190   }
 191
 192   ParseValue(aStr, transformType, aValue);
 193   return aValue.IsNull() ? NS_ERROR_FAILURE : NS_OK;
 194 }
 195
 196 void SVGAnimatedTransformList::SMILAnimatedTransformList::ParseValue(
 197     const nsAString& aSpec, const nsAtom* aTransformType, SMILValue& aResult) {
 198   MOZ_ASSERT(aResult.IsNull(), "Unexpected type for SMIL value");
 199
 200   static_assert(SVGTransformSMILData::NUM_SIMPLE_PARAMS == 3,
 201                 "SVGSMILTransform constructor should be expecting array "
 202                 "with 3 params");
 203
 204   float params[3] = {0.f};
 205   int32_t numParsed = ParseParameterList(aSpec, params, 3);
 206   uint16_t transformType;
 207
 208   if (aTransformType == nsGkAtoms::translate) {
 209     // tx [ty=0]
 210     if (numParsed != 1 && numParsed != 2) return;
 211     transformType = SVG_TRANSFORM_TRANSLATE;
 212   } else if (aTransformType == nsGkAtoms::scale) {
 213     // sx [sy=sx]
 214     if (numParsed != 1 && numParsed != 2) return;
 215     if (numParsed == 1) {
 216       params[1] = params[0];
 217     }
 218     transformType = SVG_TRANSFORM_SCALE;
 219   } else if (aTransformType == nsGkAtoms::rotate) {
 220     // r [cx=0 cy=0]
 221     if (numParsed != 1 && numParsed != 3) return;
 222     transformType = SVG_TRANSFORM_ROTATE;
 223   } else if (aTransformType == nsGkAtoms::skewX) {
 224     // x-angle
 225     if (numParsed != 1) return;
 226     transformType = SVG_TRANSFORM_SKEWX;
 227   } else if (aTransformType == nsGkAtoms::skewY) {
 228     // y-angle
 229     if (numParsed != 1) return;
 230     transformType = SVG_TRANSFORM_SKEWY;
 231   } else {
 232     return;
 233   }
 234
 235   SMILValue val(SVGTransformListSMILType::Singleton());
 236   SVGTransformSMILData transform(transformType, params);
 237   if (NS_FAILED(SVGTransformListSMILType::AppendTransform(transform, val))) {
 238     return;  // OOM
 239   }
 240
 241   // Success! Populate our outparam with parsed value.
 242   aResult = std::move(val);
 243 }
 244
 245 int32_t SVGAnimatedTransformList::SMILAnimatedTransformList::ParseParameterList(
 246     const nsAString& aSpec, float* aVars, int32_t aNVars) {
 247   int numArgsFound = 0;
 248
 249   for (const auto& token :
 250        nsCharSeparatedTokenizerTemplate<nsContentUtils::IsHTMLWhitespace,
 251                                         nsTokenizerFlags::SeparatorOptional>(
 252            aSpec, ',')
 253            .ToRange()) {
 254     float f;
 255     if (!SVGContentUtils::ParseNumber(token, f)) {
 256       return -1;
 257     }
 258     if (numArgsFound < aNVars) {
 259       aVars[numArgsFound] = f;
 260     }
 261     numArgsFound++;
 262   }
 263   return numArgsFound;
 264 }
 265
 266 SMILValue SVGAnimatedTransformList::SMILAnimatedTransformList::GetBaseValue()
 267     const {
 268   // To benefit from Return Value Optimization and avoid copy constructor calls
 269   // due to our use of return-by-value, we must return the exact same object
 270   // from ALL return points. This function must only return THIS variable:
 271   SMILValue val(SVGTransformListSMILType::Singleton());
 272   if (!SVGTransformListSMILType::AppendTransforms(mVal->mBaseVal, val)) {
 273     val = SMILValue();
 274   }
 275
 276   return val;
 277 }
 278
 279 nsresult SVGAnimatedTransformList::SMILAnimatedTransformList::SetAnimValue(
 280     const SMILValue& aNewAnimValue) {
 281   MOZ_ASSERT(aNewAnimValue.mType == SVGTransformListSMILType::Singleton(),
 282              "Unexpected type to assign animated value");
 283   SVGTransformList animVal;
 284   if (!SVGTransformListSMILType::GetTransforms(aNewAnimValue, animVal.mItems)) {
 285     return NS_ERROR_FAILURE;
 286   }
 287
 288   return mVal->SetAnimValue(animVal, mElement);
 289 }
 290
 291 void SVGAnimatedTransformList::SMILAnimatedTransformList::ClearAnimValue() {
 292   if (mVal->mAnimVal) {
 293     mVal->ClearAnimValue(mElement);
 294   }
 295 }
 296
 297 }  // namespace mozilla