dom/smil/SMILCSSValueType.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 /* representation of a value for a SMIL-animated CSS property */
   8
   9 #include "SMILCSSValueType.h"
  10
  11 #include "nsComputedDOMStyle.h"
  12 #include "nsColor.h"
  13 #include "nsCSSProps.h"
  14 #include "nsCSSValue.h"
  15 #include "nsDebug.h"
  16 #include "nsPresContextInlines.h"
  17 #include "nsPresContext.h"
  18 #include "nsString.h"
  19 #include "nsStyleUtil.h"
  20 #include "mozilla/DeclarationBlock.h"
  21 #include "mozilla/PresShell.h"
  22 #include "mozilla/PresShellInlines.h"
  23 #include "mozilla/ServoBindings.h"
  24 #include "mozilla/StyleAnimationValue.h"
  25 #include "mozilla/ServoCSSParser.h"
  26 #include "mozilla/ServoStyleSet.h"
  27 #include "mozilla/SMILParserUtils.h"
  28 #include "mozilla/SMILValue.h"
  29 #include "mozilla/dom/BaseKeyframeTypesBinding.h"
  30 #include "mozilla/dom/Document.h"
  31 #include "mozilla/dom/Element.h"
  32
  33 using namespace mozilla::dom;
  34
  35 namespace mozilla {
  36
  37 using ServoAnimationValues = CopyableAutoTArray<RefPtr<StyleAnimationValue>, 1>;
  38
  39 /*static*/
  40 SMILCSSValueType SMILCSSValueType::sSingleton;
  41
  42 struct ValueWrapper {
  43   ValueWrapper(nsCSSPropertyID aPropID, const AnimationValue& aValue)
  44       : mPropID(aPropID) {
  45     MOZ_ASSERT(!aValue.IsNull());
  46     mServoValues.AppendElement(aValue.mServo);
  47   }
  48   ValueWrapper(nsCSSPropertyID aPropID,
  49                const RefPtr<StyleAnimationValue>& aValue)
  50       : mPropID(aPropID), mServoValues{(aValue)} {}
  51   ValueWrapper(nsCSSPropertyID aPropID, ServoAnimationValues&& aValues)
  52       : mPropID(aPropID), mServoValues{std::move(aValues)} {}
  53
  54   bool operator==(const ValueWrapper& aOther) const {
  55     if (mPropID != aOther.mPropID) {
  56       return false;
  57     }
  58
  59     MOZ_ASSERT(!mServoValues.IsEmpty());
  60     size_t len = mServoValues.Length();
  61     if (len != aOther.mServoValues.Length()) {
  62       return false;
  63     }
  64     for (size_t i = 0; i < len; i++) {
  65       if (!Servo_AnimationValue_DeepEqual(mServoValues[i],
  66                                           aOther.mServoValues[i])) {
  67         return false;
  68       }
  69     }
  70     return true;
  71   }
  72
  73   bool operator!=(const ValueWrapper& aOther) const {
  74     return !(*this == aOther);
  75   }
  76
  77   nsCSSPropertyID mPropID;
  78   ServoAnimationValues mServoValues;
  79 };
  80
  81 // Helper Methods
  82 // --------------
  83
  84 // If one argument is null, this method updates it to point to "zero"
  85 // for the other argument's Unit (if applicable; otherwise, we return false).
  86 //
  87 // If neither argument is null, this method simply returns true.
  88 //
  89 // If both arguments are null, this method returns false.
  90 //
  91 // |aZeroValueStorage| should be a reference to a
  92 // RefPtr<StyleAnimationValue>. This is used where we may need to allocate a
  93 // new ServoAnimationValue to represent the appropriate zero value.
  94 //
  95 // Returns true on success, or otherwise.
  96 static bool FinalizeServoAnimationValues(
  97     const RefPtr<StyleAnimationValue>*& aValue1,
  98     const RefPtr<StyleAnimationValue>*& aValue2,
  99     RefPtr<StyleAnimationValue>& aZeroValueStorage) {
 100   if (!aValue1 && !aValue2) {
 101     return false;
 102   }
 103
 104   // Are we missing either val? (If so, it's an implied 0 in other val's units)
 105
 106   if (!aValue1) {
 107     aZeroValueStorage = Servo_AnimationValues_GetZeroValue(*aValue2).Consume();
 108     aValue1 = &aZeroValueStorage;
 109   } else if (!aValue2) {
 110     aZeroValueStorage = Servo_AnimationValues_GetZeroValue(*aValue1).Consume();
 111     aValue2 = &aZeroValueStorage;
 112   }
 113   return *aValue1 && *aValue2;
 114 }
 115
 116 static ValueWrapper* ExtractValueWrapper(SMILValue& aValue) {
 117   return static_cast<ValueWrapper*>(aValue.mU.mPtr);
 118 }
 119
 120 static const ValueWrapper* ExtractValueWrapper(const SMILValue& aValue) {
 121   return static_cast<const ValueWrapper*>(aValue.mU.mPtr);
 122 }
 123
 124 // Class methods
 125 // -------------
 126 void SMILCSSValueType::Init(SMILValue& aValue) const {
 127   MOZ_ASSERT(aValue.IsNull(), "Unexpected SMIL value type");
 128
 129   aValue.mU.mPtr = nullptr;
 130   aValue.mType = this;
 131 }
 132
 133 void SMILCSSValueType::Destroy(SMILValue& aValue) const {
 134   MOZ_ASSERT(aValue.mType == this, "Unexpected SMIL value type");
 135   delete static_cast<ValueWrapper*>(aValue.mU.mPtr);
 136   aValue.mType = SMILNullType::Singleton();
 137 }
 138
 139 nsresult SMILCSSValueType::Assign(SMILValue& aDest,
 140                                   const SMILValue& aSrc) const {
 141   MOZ_ASSERT(aDest.mType == aSrc.mType, "Incompatible SMIL types");
 142   MOZ_ASSERT(aDest.mType == this, "Unexpected SMIL value type");
 143   const ValueWrapper* srcWrapper = ExtractValueWrapper(aSrc);
 144   ValueWrapper* destWrapper = ExtractValueWrapper(aDest);
 145
 146   if (srcWrapper) {
 147     if (!destWrapper) {
 148       // barely-initialized dest -- need to alloc & copy
 149       aDest.mU.mPtr = new ValueWrapper(*srcWrapper);
 150     } else {
 151       // both already fully-initialized -- just copy straight across
 152       *destWrapper = *srcWrapper;
 153     }
 154   } else if (destWrapper) {
 155     // fully-initialized dest, barely-initialized src -- clear dest
 156     delete destWrapper;
 157     aDest.mU.mPtr = destWrapper = nullptr;
 158   }  // else, both are barely-initialized -- nothing to do.
 159
 160   return NS_OK;
 161 }
 162
 163 bool SMILCSSValueType::IsEqual(const SMILValue& aLeft,
 164                                const SMILValue& aRight) const {
 165   MOZ_ASSERT(aLeft.mType == aRight.mType, "Incompatible SMIL types");
 166   MOZ_ASSERT(aLeft.mType == this, "Unexpected SMIL value");
 167   const ValueWrapper* leftWrapper = ExtractValueWrapper(aLeft);
 168   const ValueWrapper* rightWrapper = ExtractValueWrapper(aRight);
 169
 170   if (leftWrapper) {
 171     if (rightWrapper) {
 172       // Both non-null
 173       NS_WARNING_ASSERTION(leftWrapper != rightWrapper,
 174                            "Two SMILValues with matching ValueWrapper ptr");
 175       return *leftWrapper == *rightWrapper;
 176     }
 177     // Left non-null, right null
 178     return false;
 179   }
 180   if (rightWrapper) {
 181     // Left null, right non-null
 182     return false;
 183   }
 184   // Both null
 185   return true;
 186 }
 187
 188 static bool AddOrAccumulate(SMILValue& aDest, const SMILValue& aValueToAdd,
 189                             CompositeOperation aCompositeOp, uint64_t aCount) {
 190   MOZ_ASSERT(aValueToAdd.mType == aDest.mType,
 191              "Trying to add mismatching types");
 192   MOZ_ASSERT(aValueToAdd.mType == &SMILCSSValueType::sSingleton,
 193              "Unexpected SMIL value type");
 194   MOZ_ASSERT(aCompositeOp == CompositeOperation::Add ||
 195                  aCompositeOp == CompositeOperation::Accumulate,
 196              "Composite operation should be add or accumulate");
 197   MOZ_ASSERT(aCompositeOp != CompositeOperation::Add || aCount == 1,
 198              "Count should be 1 if composite operation is add");
 199
 200   ValueWrapper* destWrapper = ExtractValueWrapper(aDest);
 201   const ValueWrapper* valueToAddWrapper = ExtractValueWrapper(aValueToAdd);
 202
 203   // If both of the values are empty just fail. This can happen in rare cases
 204   // such as when the underlying animation produced an empty value.
 205   //
 206   // Technically, it doesn't matter what we return here since in either case it
 207   // will produce the same result: an empty value.
 208   if (!destWrapper && !valueToAddWrapper) {
 209     return false;
 210   }
 211
 212   nsCSSPropertyID property =
 213       valueToAddWrapper ? valueToAddWrapper->mPropID : destWrapper->mPropID;
 214   // Special case: font-size-adjust and stroke-dasharray are explicitly
 215   // non-additive (even though StyleAnimationValue *could* support adding them)
 216   if (property == eCSSProperty_font_size_adjust ||
 217       property == eCSSProperty_stroke_dasharray) {
 218     return false;
 219   }
 220   // Skip font shorthand since it includes font-size-adjust.
 221   if (property == eCSSProperty_font) {
 222     return false;
 223   }
 224
 225   size_t len = valueToAddWrapper ? valueToAddWrapper->mServoValues.Length()
 226                                  : destWrapper->mServoValues.Length();
 227
 228   MOZ_ASSERT(!valueToAddWrapper || !destWrapper ||
 229                  valueToAddWrapper->mServoValues.Length() ==
 230                      destWrapper->mServoValues.Length(),
 231              "Both of values' length in the wrappers should be the same if "
 232              "both of them exist");
 233
 234   for (size_t i = 0; i < len; i++) {
 235     const RefPtr<StyleAnimationValue>* valueToAdd =
 236         valueToAddWrapper ? &valueToAddWrapper->mServoValues[i] : nullptr;
 237     const RefPtr<StyleAnimationValue>* destValue =
 238         destWrapper ? &destWrapper->mServoValues[i] : nullptr;
 239     RefPtr<StyleAnimationValue> zeroValueStorage;
 240     if (!FinalizeServoAnimationValues(valueToAdd, destValue,
 241                                       zeroValueStorage)) {
 242       return false;
 243     }
 244
 245     // FinalizeServoAnimationValues may have updated destValue so we should make
 246     // sure the aDest and aDestWrapper outparams are up-to-date.
 247     if (destWrapper) {
 248       destWrapper->mServoValues[i] = *destValue;
 249     } else {
 250       // aDest may be a barely-initialized "zero" destination.
 251       aDest.mU.mPtr = destWrapper = new ValueWrapper(property, *destValue);
 252       destWrapper->mServoValues.SetLength(len);
 253     }
 254
 255     RefPtr<StyleAnimationValue> result;
 256     if (aCompositeOp == CompositeOperation::Add) {
 257       result = Servo_AnimationValues_Add(*destValue, *valueToAdd).Consume();
 258     } else {
 259       result = Servo_AnimationValues_Accumulate(*destValue, *valueToAdd, aCount)
 260                    .Consume();
 261     }
 262
 263     if (!result) {
 264       return false;
 265     }
 266     destWrapper->mServoValues[i] = result;
 267   }
 268
 269   return true;
 270 }
 271
 272 nsresult SMILCSSValueType::SandwichAdd(SMILValue& aDest,
 273                                        const SMILValue& aValueToAdd) const {
 274   return AddOrAccumulate(aDest, aValueToAdd, CompositeOperation::Add, 1)
 275              ? NS_OK
 276              : NS_ERROR_FAILURE;
 277 }
 278
 279 nsresult SMILCSSValueType::Add(SMILValue& aDest, const SMILValue& aValueToAdd,
 280                                uint32_t aCount) const {
 281   return AddOrAccumulate(aDest, aValueToAdd, CompositeOperation::Accumulate,
 282                          aCount)
 283              ? NS_OK
 284              : NS_ERROR_FAILURE;
 285 }
 286
 287 nsresult SMILCSSValueType::ComputeDistance(const SMILValue& aFrom,
 288                                            const SMILValue& aTo,
 289                                            double& aDistance) const {
 290   MOZ_ASSERT(aFrom.mType == aTo.mType, "Trying to compare different types");
 291   MOZ_ASSERT(aFrom.mType == this, "Unexpected source type");
 292
 293   const ValueWrapper* fromWrapper = ExtractValueWrapper(aFrom);
 294   const ValueWrapper* toWrapper = ExtractValueWrapper(aTo);
 295   MOZ_ASSERT(toWrapper, "expecting non-null endpoint");
 296
 297   size_t len = toWrapper->mServoValues.Length();
 298   MOZ_ASSERT(!fromWrapper || fromWrapper->mServoValues.Length() == len,
 299              "From and to values length should be the same if "
 300              "The start value exists");
 301
 302   double squareDistance = 0;
 303
 304   for (size_t i = 0; i < len; i++) {
 305     const RefPtr<StyleAnimationValue>* fromValue =
 306         fromWrapper ? &fromWrapper->mServoValues[i] : nullptr;
 307     const RefPtr<StyleAnimationValue>* toValue = &toWrapper->mServoValues[i];
 308     RefPtr<StyleAnimationValue> zeroValueStorage;
 309     if (!FinalizeServoAnimationValues(fromValue, toValue, zeroValueStorage)) {
 310       return NS_ERROR_FAILURE;
 311     }
 312
 313     double distance =
 314         Servo_AnimationValues_ComputeDistance(*fromValue, *toValue);
 315     if (distance < 0.0) {
 316       return NS_ERROR_FAILURE;
 317     }
 318
 319     if (len == 1) {
 320       aDistance = distance;
 321       return NS_OK;
 322     }
 323     squareDistance += distance * distance;
 324   }
 325
 326   aDistance = sqrt(squareDistance);
 327
 328   return NS_OK;
 329 }
 330
 331 nsresult SMILCSSValueType::Interpolate(const SMILValue& aStartVal,
 332                                        const SMILValue& aEndVal,
 333                                        double aUnitDistance,
 334                                        SMILValue& aResult) const {
 335   MOZ_ASSERT(aStartVal.mType == aEndVal.mType,
 336              "Trying to interpolate different types");
 337   MOZ_ASSERT(aStartVal.mType == this, "Unexpected types for interpolation");
 338   MOZ_ASSERT(aResult.mType == this, "Unexpected result type");
 339   MOZ_ASSERT(aUnitDistance >= 0.0 && aUnitDistance <= 1.0,
 340              "unit distance value out of bounds");
 341   MOZ_ASSERT(!aResult.mU.mPtr, "expecting barely-initialized outparam");
 342
 343   const ValueWrapper* startWrapper = ExtractValueWrapper(aStartVal);
 344   const ValueWrapper* endWrapper = ExtractValueWrapper(aEndVal);
 345   MOZ_ASSERT(endWrapper, "expecting non-null endpoint");
 346
 347   // For discretely-animated properties Servo_AnimationValues_Interpolate will
 348   // perform the discrete animation (i.e. 50% flip) and return a success result.
 349   // However, SMIL has its own special discrete animation behavior that it uses
 350   // when keyTimes are specified, but we won't run that unless that this method
 351   // returns a failure to indicate that the property cannot be smoothly
 352   // interpolated, i.e. that we need to use a discrete calcMode.
 353   //
 354   // For shorthands, Servo_Property_IsDiscreteAnimatable will always return
 355   // false. That's fine since most shorthands (like 'font' and
 356   // 'text-decoration') include non-discrete components. If authors want to
 357   // treat all components as discrete then they should use calcMode="discrete".
 358   if (Servo_Property_IsDiscreteAnimatable(endWrapper->mPropID)) {
 359     return NS_ERROR_FAILURE;
 360   }
 361
 362   ServoAnimationValues results;
 363   size_t len = endWrapper->mServoValues.Length();
 364   results.SetCapacity(len);
 365   MOZ_ASSERT(!startWrapper || startWrapper->mServoValues.Length() == len,
 366              "Start and end values length should be the same if "
 367              "the start value exists");
 368   for (size_t i = 0; i < len; i++) {
 369     const RefPtr<StyleAnimationValue>* startValue =
 370         startWrapper ? &startWrapper->mServoValues[i] : nullptr;
 371     const RefPtr<StyleAnimationValue>* endValue = &endWrapper->mServoValues[i];
 372     RefPtr<StyleAnimationValue> zeroValueStorage;
 373     if (!FinalizeServoAnimationValues(startValue, endValue, zeroValueStorage)) {
 374       return NS_ERROR_FAILURE;
 375     }
 376
 377     RefPtr<StyleAnimationValue> result =
 378         Servo_AnimationValues_Interpolate(*startValue, *endValue, aUnitDistance)
 379             .Consume();
 380     if (!result) {
 381       return NS_ERROR_FAILURE;
 382     }
 383     results.AppendElement(result);
 384   }
 385   aResult.mU.mPtr = new ValueWrapper(endWrapper->mPropID, std::move(results));
 386
 387   return NS_OK;
 388 }
 389
 390 static ServoAnimationValues ValueFromStringHelper(
 391     nsCSSPropertyID aPropID, Element* aTargetElement,
 392     nsPresContext* aPresContext, const ComputedStyle* aComputedStyle,
 393     const nsAString& aString) {
 394   ServoAnimationValues result;
 395
 396   Document* doc = aTargetElement->GetComposedDoc();
 397   if (!doc) {
 398     return result;
 399   }
 400
 401   // Parse property
 402   ServoCSSParser::ParsingEnvironment env =
 403       ServoCSSParser::GetParsingEnvironment(doc);
 404   RefPtr<StyleLockedDeclarationBlock> servoDeclarationBlock =
 405       ServoCSSParser::ParseProperty(
 406           aPropID, NS_ConvertUTF16toUTF8(aString), env,
 407           StyleParsingMode::ALLOW_UNITLESS_LENGTH |
 408               StyleParsingMode::ALLOW_ALL_NUMERIC_VALUES);
 409   if (!servoDeclarationBlock) {
 410     return result;
 411   }
 412
 413   // Compute value
 414   aPresContext->StyleSet()->GetAnimationValues(
 415       servoDeclarationBlock, aTargetElement, aComputedStyle, result);
 416
 417   return result;
 418 }
 419
 420 // static
 421 void SMILCSSValueType::ValueFromString(nsCSSPropertyID aPropID,
 422                                        Element* aTargetElement,
 423                                        const nsAString& aString,
 424                                        SMILValue& aValue,
 425                                        bool* aIsContextSensitive) {
 426   MOZ_ASSERT(aValue.IsNull(), "Outparam should be null-typed");
 427   nsPresContext* presContext =
 428       nsContentUtils::GetContextForContent(aTargetElement);
 429   if (!presContext) {
 430     NS_WARNING("Not parsing animation value; unable to get PresContext");
 431     return;
 432   }
 433
 434   Document* doc = aTargetElement->GetComposedDoc();
 435   if (doc && !nsStyleUtil::CSPAllowsInlineStyle(nullptr, doc, nullptr, 0, 1,
 436                                                 aString, nullptr)) {
 437     return;
 438   }
 439
 440   RefPtr<const ComputedStyle> computedStyle =
 441       nsComputedDOMStyle::GetComputedStyle(aTargetElement);
 442   if (!computedStyle) {
 443     return;
 444   }
 445
 446   ServoAnimationValues parsedValues = ValueFromStringHelper(
 447       aPropID, aTargetElement, presContext, computedStyle, aString);
 448   if (aIsContextSensitive) {
 449     // FIXME: Bug 1358955 - detect context-sensitive values and set this value
 450     // appropriately.
 451     *aIsContextSensitive = false;
 452   }
 453
 454   if (!parsedValues.IsEmpty()) {
 455     sSingleton.Init(aValue);
 456     aValue.mU.mPtr = new ValueWrapper(aPropID, std::move(parsedValues));
 457   }
 458 }
 459
 460 // static
 461 SMILValue SMILCSSValueType::ValueFromAnimationValue(
 462     nsCSSPropertyID aPropID, Element* aTargetElement,
 463     const AnimationValue& aValue) {
 464   SMILValue result;
 465
 466   Document* doc = aTargetElement->GetComposedDoc();
 467   // We'd like to avoid serializing |aValue| if possible, and since the
 468   // string passed to CSPAllowsInlineStyle is only used for reporting violations
 469   // and an intermediate CSS value is not likely to be particularly useful
 470   // in that case, we just use a generic placeholder string instead.
 471   static const nsLiteralString kPlaceholderText = u"[SVG animation of CSS]"_ns;
 472   if (doc && !nsStyleUtil::CSPAllowsInlineStyle(nullptr, doc, nullptr, 0, 1,
 473                                                 kPlaceholderText, nullptr)) {
 474     return result;
 475   }
 476
 477   sSingleton.Init(result);
 478   result.mU.mPtr = new ValueWrapper(aPropID, aValue);
 479
 480   return result;
 481 }
 482
 483 // static
 484 bool SMILCSSValueType::SetPropertyValues(const SMILValue& aValue,
 485                                          DeclarationBlock& aDecl) {
 486   MOZ_ASSERT(aValue.mType == &SMILCSSValueType::sSingleton,
 487              "Unexpected SMIL value type");
 488   const ValueWrapper* wrapper = ExtractValueWrapper(aValue);
 489   if (!wrapper) {
 490     return false;
 491   }
 492
 493   bool changed = false;
 494   for (const auto& value : wrapper->mServoValues) {
 495     changed |= Servo_DeclarationBlock_SetPropertyToAnimationValue(aDecl.Raw(),
 496                                                                   value, {});
 497   }
 498
 499   return changed;
 500 }
 501
 502 // static
 503 nsCSSPropertyID SMILCSSValueType::PropertyFromValue(const SMILValue& aValue) {
 504   if (aValue.mType != &SMILCSSValueType::sSingleton) {
 505     return eCSSProperty_UNKNOWN;
 506   }
 507
 508   const ValueWrapper* wrapper = ExtractValueWrapper(aValue);
 509   if (!wrapper) {
 510     return eCSSProperty_UNKNOWN;
 511   }
 512
 513   return wrapper->mPropID;
 514 }
 515
 516 // static
 517 void SMILCSSValueType::FinalizeValue(SMILValue& aValue,
 518                                      const SMILValue& aValueToMatch) {
 519   MOZ_ASSERT(aValue.mType == aValueToMatch.mType, "Incompatible SMIL types");
 520   MOZ_ASSERT(aValue.mType == &SMILCSSValueType::sSingleton,
 521              "Unexpected SMIL value type");
 522
 523   ValueWrapper* valueWrapper = ExtractValueWrapper(aValue);
 524   // If |aValue| already has a value, there's nothing to do here.
 525   if (valueWrapper) {
 526     return;
 527   }
 528
 529   const ValueWrapper* valueToMatchWrapper = ExtractValueWrapper(aValueToMatch);
 530   if (!valueToMatchWrapper) {
 531     MOZ_ASSERT_UNREACHABLE("Value to match is empty");
 532     return;
 533   }
 534
 535   ServoAnimationValues zeroValues;
 536   zeroValues.SetCapacity(valueToMatchWrapper->mServoValues.Length());
 537
 538   for (const auto& valueToMatch : valueToMatchWrapper->mServoValues) {
 539     RefPtr<StyleAnimationValue> zeroValue =
 540         Servo_AnimationValues_GetZeroValue(valueToMatch).Consume();
 541     if (!zeroValue) {
 542       return;
 543     }
 544     zeroValues.AppendElement(std::move(zeroValue));
 545   }
 546   aValue.mU.mPtr =
 547       new ValueWrapper(valueToMatchWrapper->mPropID, std::move(zeroValues));
 548 }
 549
 550 }  // namespace mozilla