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Diffstat (limited to 'dom/animation/KeyframeUtils.cpp')
| -rw-r--r-- | dom/animation/KeyframeUtils.cpp | 1251 |
1 files changed, 1251 insertions, 0 deletions
diff --git a/dom/animation/KeyframeUtils.cpp b/dom/animation/KeyframeUtils.cpp new file mode 100644 index 0000000000..acb1a8f257 --- /dev/null +++ b/dom/animation/KeyframeUtils.cpp @@ -0,0 +1,1251 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/KeyframeUtils.h" + +#include <algorithm> // For std::stable_sort, std::min +#include <utility> + +#include "js/ForOfIterator.h" // For JS::ForOfIterator +#include "jsapi.h" // For most JSAPI +#include "mozilla/ComputedStyle.h" +#include "mozilla/ErrorResult.h" +#include "mozilla/RangedArray.h" +#include "mozilla/ServoBindingTypes.h" +#include "mozilla/ServoBindings.h" +#include "mozilla/ServoCSSParser.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StyleAnimationValue.h" +#include "mozilla/TimingParams.h" +#include "mozilla/dom/BaseKeyframeTypesBinding.h" // For FastBaseKeyframe etc. +#include "mozilla/dom/BindingCallContext.h" +#include "mozilla/dom/Document.h" // For Document::AreWebAnimationsImplicitKeyframesEnabled +#include "mozilla/dom/Element.h" +#include "mozilla/dom/KeyframeEffect.h" // For PropertyValuesPair etc. +#include "mozilla/dom/KeyframeEffectBinding.h" +#include "mozilla/dom/Nullable.h" +#include "nsCSSPropertyIDSet.h" +#include "nsCSSProps.h" +#include "nsCSSPseudoElements.h" // For PseudoStyleType +#include "nsClassHashtable.h" +#include "nsContentUtils.h" // For GetContextForContent +#include "nsIScriptError.h" +#include "nsPresContextInlines.h" +#include "nsTArray.h" + +using mozilla::dom::Nullable; + +namespace mozilla { + +// ------------------------------------------------------------------ +// +// Internal data types +// +// ------------------------------------------------------------------ + +// For the aAllowList parameter of AppendStringOrStringSequence and +// GetPropertyValuesPairs. +enum class ListAllowance { eDisallow, eAllow }; + +/** + * A property-values pair obtained from the open-ended properties + * discovered on a regular keyframe or property-indexed keyframe object. + * + * Single values (as required by a regular keyframe, and as also supported + * on property-indexed keyframes) are stored as the only element in + * mValues. + */ +struct PropertyValuesPair { + nsCSSPropertyID mProperty; + nsTArray<nsCString> mValues; +}; + +/** + * An additional property (for a property-values pair) found on a + * BaseKeyframe or BasePropertyIndexedKeyframe object. + */ +struct AdditionalProperty { + nsCSSPropertyID mProperty; + size_t mJsidIndex; // Index into |ids| in GetPropertyValuesPairs. + + struct PropertyComparator { + bool Equals(const AdditionalProperty& aLhs, + const AdditionalProperty& aRhs) const { + return aLhs.mProperty == aRhs.mProperty; + } + bool LessThan(const AdditionalProperty& aLhs, + const AdditionalProperty& aRhs) const { + return nsCSSProps::PropertyIDLNameSortPosition(aLhs.mProperty) < + nsCSSProps::PropertyIDLNameSortPosition(aRhs.mProperty); + } + }; +}; + +/** + * Data for a segment in a keyframe animation of a given property + * whose value is a StyleAnimationValue. + * + * KeyframeValueEntry is used in GetAnimationPropertiesFromKeyframes + * to gather data for each individual segment. + */ +struct KeyframeValueEntry { + nsCSSPropertyID mProperty; + AnimationValue mValue; + + float mOffset; + Maybe<ComputedTimingFunction> mTimingFunction; + dom::CompositeOperation mComposite; + + struct PropertyOffsetComparator { + static bool Equals(const KeyframeValueEntry& aLhs, + const KeyframeValueEntry& aRhs) { + return aLhs.mProperty == aRhs.mProperty && aLhs.mOffset == aRhs.mOffset; + } + static bool LessThan(const KeyframeValueEntry& aLhs, + const KeyframeValueEntry& aRhs) { + // First, sort by property IDL name. + int32_t order = nsCSSProps::PropertyIDLNameSortPosition(aLhs.mProperty) - + nsCSSProps::PropertyIDLNameSortPosition(aRhs.mProperty); + if (order != 0) { + return order < 0; + } + + // Then, by offset. + return aLhs.mOffset < aRhs.mOffset; + } + }; +}; + +class ComputedOffsetComparator { + public: + static bool Equals(const Keyframe& aLhs, const Keyframe& aRhs) { + return aLhs.mComputedOffset == aRhs.mComputedOffset; + } + + static bool LessThan(const Keyframe& aLhs, const Keyframe& aRhs) { + return aLhs.mComputedOffset < aRhs.mComputedOffset; + } +}; + +// ------------------------------------------------------------------ +// +// Internal helper method declarations +// +// ------------------------------------------------------------------ + +static void GetKeyframeListFromKeyframeSequence( + JSContext* aCx, dom::Document* aDocument, JS::ForOfIterator& aIterator, + nsTArray<Keyframe>& aResult, const char* aContext, ErrorResult& aRv); + +static bool ConvertKeyframeSequence(JSContext* aCx, dom::Document* aDocument, + JS::ForOfIterator& aIterator, + const char* aContext, + nsTArray<Keyframe>& aResult); + +static bool GetPropertyValuesPairs(JSContext* aCx, + JS::Handle<JSObject*> aObject, + ListAllowance aAllowLists, + nsTArray<PropertyValuesPair>& aResult); + +static bool AppendStringOrStringSequenceToArray(JSContext* aCx, + JS::Handle<JS::Value> aValue, + ListAllowance aAllowLists, + nsTArray<nsCString>& aValues); + +static bool AppendValueAsString(JSContext* aCx, nsTArray<nsCString>& aValues, + JS::Handle<JS::Value> aValue); + +static Maybe<PropertyValuePair> MakePropertyValuePair( + nsCSSPropertyID aProperty, const nsACString& aStringValue, + dom::Document* aDocument); + +static bool HasValidOffsets(const nsTArray<Keyframe>& aKeyframes); + +#ifdef DEBUG +static void MarkAsComputeValuesFailureKey(PropertyValuePair& aPair); + +#endif + +static nsTArray<ComputedKeyframeValues> GetComputedKeyframeValues( + const nsTArray<Keyframe>& aKeyframes, dom::Element* aElement, + PseudoStyleType aPseudoType, const ComputedStyle* aComputedValues); + +static void BuildSegmentsFromValueEntries( + nsTArray<KeyframeValueEntry>& aEntries, + nsTArray<AnimationProperty>& aResult); + +static void GetKeyframeListFromPropertyIndexedKeyframe( + JSContext* aCx, dom::Document* aDocument, JS::Handle<JS::Value> aValue, + nsTArray<Keyframe>& aResult, ErrorResult& aRv); + +static bool HasImplicitKeyframeValues(const nsTArray<Keyframe>& aKeyframes, + dom::Document* aDocument); + +static void DistributeRange(const Range<Keyframe>& aRange); + +// ------------------------------------------------------------------ +// +// Public API +// +// ------------------------------------------------------------------ + +/* static */ +nsTArray<Keyframe> KeyframeUtils::GetKeyframesFromObject( + JSContext* aCx, dom::Document* aDocument, JS::Handle<JSObject*> aFrames, + const char* aContext, ErrorResult& aRv) { + MOZ_ASSERT(!aRv.Failed()); + + nsTArray<Keyframe> keyframes; + + if (!aFrames) { + // The argument was explicitly null meaning no keyframes. + return keyframes; + } + + // At this point we know we have an object. We try to convert it to a + // sequence of keyframes first, and if that fails due to not being iterable, + // we try to convert it to a property-indexed keyframe. + JS::Rooted<JS::Value> objectValue(aCx, JS::ObjectValue(*aFrames)); + JS::ForOfIterator iter(aCx); + if (!iter.init(objectValue, JS::ForOfIterator::AllowNonIterable)) { + aRv.Throw(NS_ERROR_FAILURE); + return keyframes; + } + + if (iter.valueIsIterable()) { + GetKeyframeListFromKeyframeSequence(aCx, aDocument, iter, keyframes, + aContext, aRv); + } else { + GetKeyframeListFromPropertyIndexedKeyframe(aCx, aDocument, objectValue, + keyframes, aRv); + } + + if (aRv.Failed()) { + MOZ_ASSERT(keyframes.IsEmpty(), + "Should not set any keyframes when there is an error"); + return keyframes; + } + + if (!dom::Document::AreWebAnimationsImplicitKeyframesEnabled(aCx, nullptr) && + HasImplicitKeyframeValues(keyframes, aDocument)) { + keyframes.Clear(); + aRv.Throw(NS_ERROR_DOM_ANIM_MISSING_PROPS_ERR); + } + + return keyframes; +} + +/* static */ +void KeyframeUtils::DistributeKeyframes(nsTArray<Keyframe>& aKeyframes) { + if (aKeyframes.IsEmpty()) { + return; + } + + // If the first keyframe has an unspecified offset, fill it in with 0%. + // If there is only a single keyframe, then it gets 100%. + if (aKeyframes.Length() > 1) { + Keyframe& firstElement = aKeyframes[0]; + firstElement.mComputedOffset = firstElement.mOffset.valueOr(0.0); + // We will fill in the last keyframe's offset below + } else { + Keyframe& lastElement = aKeyframes.LastElement(); + lastElement.mComputedOffset = lastElement.mOffset.valueOr(1.0); + } + + // Fill in remaining missing offsets. + const Keyframe* const last = &aKeyframes.LastElement(); + const RangedPtr<Keyframe> begin(aKeyframes.Elements(), aKeyframes.Length()); + RangedPtr<Keyframe> keyframeA = begin; + while (keyframeA != last) { + // Find keyframe A and keyframe B *between* which we will apply spacing. + RangedPtr<Keyframe> keyframeB = keyframeA + 1; + while (keyframeB->mOffset.isNothing() && keyframeB != last) { + ++keyframeB; + } + keyframeB->mComputedOffset = keyframeB->mOffset.valueOr(1.0); + + // Fill computed offsets in (keyframe A, keyframe B). + DistributeRange(Range<Keyframe>(keyframeA, keyframeB + 1)); + keyframeA = keyframeB; + } +} + +/* static */ +nsTArray<AnimationProperty> KeyframeUtils::GetAnimationPropertiesFromKeyframes( + const nsTArray<Keyframe>& aKeyframes, dom::Element* aElement, + PseudoStyleType aPseudoType, const ComputedStyle* aStyle, + dom::CompositeOperation aEffectComposite) { + nsTArray<AnimationProperty> result; + + const nsTArray<ComputedKeyframeValues> computedValues = + GetComputedKeyframeValues(aKeyframes, aElement, aPseudoType, aStyle); + if (computedValues.IsEmpty()) { + // In rare cases GetComputedKeyframeValues might fail and return an empty + // array, in which case we likewise return an empty array from here. + return result; + } + + MOZ_ASSERT(aKeyframes.Length() == computedValues.Length(), + "Array length mismatch"); + + nsTArray<KeyframeValueEntry> entries(aKeyframes.Length()); + + const size_t len = aKeyframes.Length(); + for (size_t i = 0; i < len; ++i) { + const Keyframe& frame = aKeyframes[i]; + for (auto& value : computedValues[i]) { + MOZ_ASSERT(frame.mComputedOffset != Keyframe::kComputedOffsetNotSet, + "Invalid computed offset"); + KeyframeValueEntry* entry = entries.AppendElement(); + entry->mOffset = frame.mComputedOffset; + entry->mProperty = value.mProperty; + entry->mValue = value.mValue; + entry->mTimingFunction = frame.mTimingFunction; + // The following assumes that CompositeOperation is a strict subset of + // CompositeOperationOrAuto. + entry->mComposite = + frame.mComposite == dom::CompositeOperationOrAuto::Auto + ? aEffectComposite + : static_cast<dom::CompositeOperation>(frame.mComposite); + } + } + + BuildSegmentsFromValueEntries(entries, result); + return result; +} + +/* static */ +bool KeyframeUtils::IsAnimatableProperty(nsCSSPropertyID aProperty) { + // Regardless of the backend type, treat the 'display' property as not + // animatable. (Servo will report it as being animatable, since it is + // in fact animatable by SMIL.) + if (aProperty == eCSSProperty_display) { + return false; + } + return Servo_Property_IsAnimatable(aProperty); +} + +// ------------------------------------------------------------------ +// +// Internal helpers +// +// ------------------------------------------------------------------ + +/** + * Converts a JS object to an IDL sequence<Keyframe>. + * + * @param aCx The JSContext corresponding to |aIterator|. + * @param aDocument The document to use when parsing CSS properties. + * @param aIterator An already-initialized ForOfIterator for the JS + * object to iterate over as a sequence. + * @param aResult The array into which the resulting Keyframe objects will be + * appended. + * @param aContext The context string to prepend to thrown exceptions. + * @param aRv Out param to store any errors thrown by this function. + */ +static void GetKeyframeListFromKeyframeSequence( + JSContext* aCx, dom::Document* aDocument, JS::ForOfIterator& aIterator, + nsTArray<Keyframe>& aResult, const char* aContext, ErrorResult& aRv) { + MOZ_ASSERT(!aRv.Failed()); + MOZ_ASSERT(aResult.IsEmpty()); + + // Convert the object in aIterator to a sequence of keyframes producing + // an array of Keyframe objects. + if (!ConvertKeyframeSequence(aCx, aDocument, aIterator, aContext, aResult)) { + aResult.Clear(); + aRv.NoteJSContextException(aCx); + return; + } + + // If the sequence<> had zero elements, we won't generate any + // keyframes. + if (aResult.IsEmpty()) { + return; + } + + // Check that the keyframes are loosely sorted and with values all + // between 0% and 100%. + if (!HasValidOffsets(aResult)) { + aResult.Clear(); + aRv.ThrowTypeError<dom::MSG_INVALID_KEYFRAME_OFFSETS>(); + return; + } +} + +/** + * Converts a JS object wrapped by the given JS::ForIfIterator to an + * IDL sequence<Keyframe> and stores the resulting Keyframe objects in + * aResult. + */ +static bool ConvertKeyframeSequence(JSContext* aCx, dom::Document* aDocument, + JS::ForOfIterator& aIterator, + const char* aContext, + nsTArray<Keyframe>& aResult) { + JS::Rooted<JS::Value> value(aCx); + // Parsing errors should only be reported after we have finished iterating + // through all values. If we have any early returns while iterating, we should + // ignore parsing errors. + IgnoredErrorResult parseEasingResult; + + for (;;) { + bool done; + if (!aIterator.next(&value, &done)) { + return false; + } + if (done) { + break; + } + // Each value found when iterating the object must be an object + // or null/undefined (which gets treated as a default {} dictionary + // value). + if (!value.isObject() && !value.isNullOrUndefined()) { + dom::ThrowErrorMessage<dom::MSG_NOT_OBJECT>( + aCx, aContext, "Element of sequence<Keyframe> argument"); + return false; + } + + // Convert the JS value into a BaseKeyframe dictionary value. + dom::binding_detail::FastBaseKeyframe keyframeDict; + dom::BindingCallContext callCx(aCx, aContext); + if (!keyframeDict.Init(callCx, value, + "Element of sequence<Keyframe> argument")) { + // This may happen if the value type of the member of BaseKeyframe is + // invalid. e.g. `offset` only accept a double value, so if we provide a + // string, we enter this branch. + // Besides, keyframeDict.Init() should throw a Type Error message already, + // so we don't have to do it again. + return false; + } + + Keyframe* keyframe = aResult.AppendElement(fallible); + if (!keyframe) { + return false; + } + + if (!keyframeDict.mOffset.IsNull()) { + keyframe->mOffset.emplace(keyframeDict.mOffset.Value()); + } + + if (StaticPrefs::dom_animations_api_compositing_enabled()) { + keyframe->mComposite = keyframeDict.mComposite; + } + + // Look for additional property-values pairs on the object. + nsTArray<PropertyValuesPair> propertyValuePairs; + if (value.isObject()) { + JS::Rooted<JSObject*> object(aCx, &value.toObject()); + if (!GetPropertyValuesPairs(aCx, object, ListAllowance::eDisallow, + propertyValuePairs)) { + return false; + } + } + + if (!parseEasingResult.Failed()) { + keyframe->mTimingFunction = + TimingParams::ParseEasing(keyframeDict.mEasing, parseEasingResult); + // Even if the above fails, we still need to continue reading off all the + // properties since checking the validity of easing should be treated as + // a separate step that happens *after* all the other processing in this + // loop since (since it is never likely to be handled by WebIDL unlike the + // rest of this loop). + } + + for (PropertyValuesPair& pair : propertyValuePairs) { + MOZ_ASSERT(pair.mValues.Length() == 1); + + Maybe<PropertyValuePair> valuePair = + MakePropertyValuePair(pair.mProperty, pair.mValues[0], aDocument); + if (!valuePair) { + continue; + } + keyframe->mPropertyValues.AppendElement(std::move(valuePair.ref())); + +#ifdef DEBUG + // When we go to convert keyframes into arrays of property values we + // call StyleAnimation::ComputeValues. This should normally return true + // but in order to test the case where it does not, BaseKeyframeDict + // includes a chrome-only member that can be set to indicate that + // ComputeValues should fail for shorthand property values on that + // keyframe. + if (nsCSSProps::IsShorthand(pair.mProperty) && + keyframeDict.mSimulateComputeValuesFailure) { + MarkAsComputeValuesFailureKey(keyframe->mPropertyValues.LastElement()); + } +#endif + } + } + + // Throw any errors we encountered while parsing 'easing' properties. + if (parseEasingResult.MaybeSetPendingException(aCx)) { + return false; + } + + return true; +} + +/** + * Reads the property-values pairs from the specified JS object. + * + * @param aObject The JS object to look at. + * @param aAllowLists If eAllow, values will be converted to + * (DOMString or sequence<DOMString); if eDisallow, values + * will be converted to DOMString. + * @param aResult The array into which the enumerated property-values + * pairs will be stored. + * @return false on failure or JS exception thrown while interacting + * with aObject; true otherwise. + */ +static bool GetPropertyValuesPairs(JSContext* aCx, + JS::Handle<JSObject*> aObject, + ListAllowance aAllowLists, + nsTArray<PropertyValuesPair>& aResult) { + nsTArray<AdditionalProperty> properties; + + // Iterate over all the properties on aObject and append an + // entry to properties for them. + // + // We don't compare the jsids that we encounter with those for + // the explicit dictionary members, since we know that none + // of the CSS property IDL names clash with them. + JS::Rooted<JS::IdVector> ids(aCx, JS::IdVector(aCx)); + if (!JS_Enumerate(aCx, aObject, &ids)) { + return false; + } + for (size_t i = 0, n = ids.length(); i < n; i++) { + nsAutoJSCString propName; + if (!propName.init(aCx, ids[i])) { + return false; + } + + // Basically, we have to handle "cssOffset" and "cssFloat" specially here: + // "cssOffset" => eCSSProperty_offset + // "cssFloat" => eCSSProperty_float + // This means if the attribute is the string "cssOffset"/"cssFloat", we use + // CSS "offset"/"float" property. + // https://drafts.csswg.org/web-animations/#property-name-conversion + nsCSSPropertyID property = nsCSSPropertyID::eCSSProperty_UNKNOWN; + if (propName.EqualsLiteral("cssOffset")) { + property = nsCSSPropertyID::eCSSProperty_offset; + } else if (propName.EqualsLiteral("cssFloat")) { + property = nsCSSPropertyID::eCSSProperty_float; + } else if (!propName.EqualsLiteral("offset") && + !propName.EqualsLiteral("float")) { + property = nsCSSProps::LookupPropertyByIDLName( + propName, CSSEnabledState::ForAllContent); + } + + if (KeyframeUtils::IsAnimatableProperty(property)) { + AdditionalProperty* p = properties.AppendElement(); + p->mProperty = property; + p->mJsidIndex = i; + } + } + + // Sort the entries by IDL name and then get each value and + // convert it either to a DOMString or to a + // (DOMString or sequence<DOMString>), depending on aAllowLists, + // and build up aResult. + properties.Sort(AdditionalProperty::PropertyComparator()); + + for (AdditionalProperty& p : properties) { + JS::Rooted<JS::Value> value(aCx); + if (!JS_GetPropertyById(aCx, aObject, ids[p.mJsidIndex], &value)) { + return false; + } + PropertyValuesPair* pair = aResult.AppendElement(); + pair->mProperty = p.mProperty; + if (!AppendStringOrStringSequenceToArray(aCx, value, aAllowLists, + pair->mValues)) { + return false; + } + } + + return true; +} + +/** + * Converts aValue to DOMString, if aAllowLists is eDisallow, or + * to (DOMString or sequence<DOMString>) if aAllowLists is aAllow. + * The resulting strings are appended to aValues. + */ +static bool AppendStringOrStringSequenceToArray(JSContext* aCx, + JS::Handle<JS::Value> aValue, + ListAllowance aAllowLists, + nsTArray<nsCString>& aValues) { + if (aAllowLists == ListAllowance::eAllow && aValue.isObject()) { + // The value is an object, and we want to allow lists; convert + // aValue to (DOMString or sequence<DOMString>). + JS::ForOfIterator iter(aCx); + if (!iter.init(aValue, JS::ForOfIterator::AllowNonIterable)) { + return false; + } + if (iter.valueIsIterable()) { + // If the object is iterable, convert it to sequence<DOMString>. + JS::Rooted<JS::Value> element(aCx); + for (;;) { + bool done; + if (!iter.next(&element, &done)) { + return false; + } + if (done) { + break; + } + if (!AppendValueAsString(aCx, aValues, element)) { + return false; + } + } + return true; + } + } + + // Either the object is not iterable, or aAllowLists doesn't want + // a list; convert it to DOMString. + if (!AppendValueAsString(aCx, aValues, aValue)) { + return false; + } + + return true; +} + +/** + * Converts aValue to DOMString and appends it to aValues. + */ +static bool AppendValueAsString(JSContext* aCx, nsTArray<nsCString>& aValues, + JS::Handle<JS::Value> aValue) { + return ConvertJSValueToString(aCx, aValue, dom::eStringify, dom::eStringify, + *aValues.AppendElement()); +} + +static void ReportInvalidPropertyValueToConsole( + nsCSSPropertyID aProperty, const nsACString& aInvalidPropertyValue, + dom::Document* aDoc) { + AutoTArray<nsString, 2> params; + params.AppendElement(NS_ConvertUTF8toUTF16(aInvalidPropertyValue)); + CopyASCIItoUTF16(nsCSSProps::GetStringValue(aProperty), + *params.AppendElement()); + nsContentUtils::ReportToConsole(nsIScriptError::warningFlag, "Animation"_ns, + aDoc, nsContentUtils::eDOM_PROPERTIES, + "InvalidKeyframePropertyValue", params); +} + +/** + * Construct a PropertyValuePair parsing the given string into a suitable + * nsCSSValue object. + * + * @param aProperty The CSS property. + * @param aStringValue The property value to parse. + * @param aDocument The document to use when parsing. + * @return The constructed PropertyValuePair, or Nothing() if |aStringValue| is + * an invalid property value. + */ +static Maybe<PropertyValuePair> MakePropertyValuePair( + nsCSSPropertyID aProperty, const nsACString& aStringValue, + dom::Document* aDocument) { + MOZ_ASSERT(aDocument); + Maybe<PropertyValuePair> result; + + ServoCSSParser::ParsingEnvironment env = + ServoCSSParser::GetParsingEnvironment(aDocument); + RefPtr<RawServoDeclarationBlock> servoDeclarationBlock = + ServoCSSParser::ParseProperty(aProperty, aStringValue, env); + + if (servoDeclarationBlock) { + result.emplace(aProperty, std::move(servoDeclarationBlock)); + } else { + ReportInvalidPropertyValueToConsole(aProperty, aStringValue, aDocument); + } + return result; +} + +/** + * Checks that the given keyframes are loosely ordered (each keyframe's + * offset that is not null is greater than or equal to the previous + * non-null offset) and that all values are within the range [0.0, 1.0]. + * + * @return true if the keyframes' offsets are correctly ordered and + * within range; false otherwise. + */ +static bool HasValidOffsets(const nsTArray<Keyframe>& aKeyframes) { + double offset = 0.0; + for (const Keyframe& keyframe : aKeyframes) { + if (keyframe.mOffset) { + double thisOffset = keyframe.mOffset.value(); + if (thisOffset < offset || thisOffset > 1.0f) { + return false; + } + offset = thisOffset; + } + } + return true; +} + +#ifdef DEBUG +/** + * Takes a property-value pair for a shorthand property and modifies the + * value to indicate that when we call StyleAnimationValue::ComputeValues on + * that value we should behave as if that function had failed. + * + * @param aPair The PropertyValuePair to modify. |aPair.mProperty| must be + * a shorthand property. + */ +static void MarkAsComputeValuesFailureKey(PropertyValuePair& aPair) { + MOZ_ASSERT(nsCSSProps::IsShorthand(aPair.mProperty), + "Only shorthand property values can be marked as failure values"); + + aPair.mSimulateComputeValuesFailure = true; +} + +#endif + +/** + * The variation of the above function. This is for Servo backend. + */ +static nsTArray<ComputedKeyframeValues> GetComputedKeyframeValues( + const nsTArray<Keyframe>& aKeyframes, dom::Element* aElement, + PseudoStyleType aPseudoType, const ComputedStyle* aComputedStyle) { + MOZ_ASSERT(aElement); + + nsTArray<ComputedKeyframeValues> result; + + nsPresContext* presContext = nsContentUtils::GetContextForContent(aElement); + if (!presContext) { + // This has been reported to happen with some combinations of content + // (particularly involving resize events and layout flushes? See bug 1407898 + // and bug 1408420) but no reproducible steps have been found. + // For now we just return an empty array. + return result; + } + + result = presContext->StyleSet()->GetComputedKeyframeValuesFor( + aKeyframes, aElement, aPseudoType, aComputedStyle); + return result; +} + +static void AppendInitialSegment(AnimationProperty* aAnimationProperty, + const KeyframeValueEntry& aFirstEntry) { + AnimationPropertySegment* segment = + aAnimationProperty->mSegments.AppendElement(); + segment->mFromKey = 0.0f; + segment->mToKey = aFirstEntry.mOffset; + segment->mToValue = aFirstEntry.mValue; + segment->mToComposite = aFirstEntry.mComposite; +} + +static void AppendFinalSegment(AnimationProperty* aAnimationProperty, + const KeyframeValueEntry& aLastEntry) { + AnimationPropertySegment* segment = + aAnimationProperty->mSegments.AppendElement(); + segment->mFromKey = aLastEntry.mOffset; + segment->mFromValue = aLastEntry.mValue; + segment->mFromComposite = aLastEntry.mComposite; + segment->mToKey = 1.0f; + segment->mTimingFunction = aLastEntry.mTimingFunction; +} + +// Returns a newly created AnimationProperty if one was created to fill-in the +// missing keyframe, nullptr otherwise (if we decided not to fill the keyframe +// becase we don't support implicit keyframes). +static AnimationProperty* HandleMissingInitialKeyframe( + nsTArray<AnimationProperty>& aResult, const KeyframeValueEntry& aEntry) { + MOZ_ASSERT(aEntry.mOffset != 0.0f, + "The offset of the entry should not be 0.0"); + + // If the preference for implicit keyframes is not enabled, don't fill in the + // missing keyframe. + if (!StaticPrefs::dom_animations_api_implicit_keyframes_enabled()) { + return nullptr; + } + + AnimationProperty* result = aResult.AppendElement(); + result->mProperty = aEntry.mProperty; + + AppendInitialSegment(result, aEntry); + + return result; +} + +static void HandleMissingFinalKeyframe( + nsTArray<AnimationProperty>& aResult, const KeyframeValueEntry& aEntry, + AnimationProperty* aCurrentAnimationProperty) { + MOZ_ASSERT(aEntry.mOffset != 1.0f, + "The offset of the entry should not be 1.0"); + + // If the preference for implicit keyframes is not enabled, don't fill + // in the missing keyframe. + if (!StaticPrefs::dom_animations_api_implicit_keyframes_enabled()) { + // If we have already appended a new entry for the property so we have to + // remove it. + if (aCurrentAnimationProperty) { + aResult.RemoveLastElement(); + } + return; + } + + // If |aCurrentAnimationProperty| is nullptr, that means this is the first + // entry for the property, we have to append a new AnimationProperty for this + // property. + if (!aCurrentAnimationProperty) { + aCurrentAnimationProperty = aResult.AppendElement(); + aCurrentAnimationProperty->mProperty = aEntry.mProperty; + + // If we have only one entry whose offset is neither 1 nor 0 for this + // property, we need to append the initial segment as well. + if (aEntry.mOffset != 0.0f) { + AppendInitialSegment(aCurrentAnimationProperty, aEntry); + } + } + AppendFinalSegment(aCurrentAnimationProperty, aEntry); +} + +/** + * Builds an array of AnimationProperty objects to represent the keyframe + * animation segments in aEntries. + */ +static void BuildSegmentsFromValueEntries( + nsTArray<KeyframeValueEntry>& aEntries, + nsTArray<AnimationProperty>& aResult) { + if (aEntries.IsEmpty()) { + return; + } + + // Sort the KeyframeValueEntry objects so that all entries for a given + // property are together, and the entries are sorted by offset otherwise. + std::stable_sort(aEntries.begin(), aEntries.end(), + &KeyframeValueEntry::PropertyOffsetComparator::LessThan); + + // For a given index i, we want to generate a segment from aEntries[i] + // to aEntries[j], if: + // + // * j > i, + // * aEntries[i + 1]'s offset/property is different from aEntries[i]'s, and + // * aEntries[j - 1]'s offset/property is different from aEntries[j]'s. + // + // That will eliminate runs of same offset/property values where there's no + // point generating zero length segments in the middle of the animation. + // + // Additionally we need to generate a zero length segment at offset 0 and at + // offset 1, if we have multiple values for a given property at that offset, + // since we need to retain the very first and very last value so they can + // be used for reverse and forward filling. + // + // Typically, for each property in |aEntries|, we expect there to be at least + // one KeyframeValueEntry with offset 0.0, and at least one with offset 1.0. + // However, since it is possible that when building |aEntries|, the call to + // StyleAnimationValue::ComputeValues might fail, this can't be guaranteed. + // Furthermore, if additive animation is disabled, the following loop takes + // care to identify properties that lack a value at offset 0.0/1.0 and drops + // those properties from |aResult|. + + nsCSSPropertyID lastProperty = eCSSProperty_UNKNOWN; + AnimationProperty* animationProperty = nullptr; + + size_t i = 0, n = aEntries.Length(); + + while (i < n) { + // If we've reached the end of the array of entries, synthesize a final (and + // initial) segment if necessary. + if (i + 1 == n) { + if (aEntries[i].mOffset != 1.0f) { + HandleMissingFinalKeyframe(aResult, aEntries[i], animationProperty); + } else if (aEntries[i].mOffset == 1.0f && !animationProperty) { + // If the last entry with offset 1 and no animation property, that means + // it is the only entry for this property so append a single segment + // from 0 offset to |aEntry[i].offset|. + Unused << HandleMissingInitialKeyframe(aResult, aEntries[i]); + } + animationProperty = nullptr; + break; + } + + MOZ_ASSERT(aEntries[i].mProperty != eCSSProperty_UNKNOWN && + aEntries[i + 1].mProperty != eCSSProperty_UNKNOWN, + "Each entry should specify a valid property"); + + // No keyframe for this property at offset 0. + if (aEntries[i].mProperty != lastProperty && aEntries[i].mOffset != 0.0f) { + // If we don't support additive animation we can't fill in the missing + // keyframes and we should just skip this property altogether. Since the + // entries are sorted by offset for a given property, and since we don't + // update |lastProperty|, we will keep hitting this condition until we + // change property. + animationProperty = HandleMissingInitialKeyframe(aResult, aEntries[i]); + if (animationProperty) { + lastProperty = aEntries[i].mProperty; + } else { + // Skip this entry if we did not handle the missing entry. + ++i; + continue; + } + } + + // Skip this entry if the next entry has the same offset except for initial + // and final ones. We will handle missing keyframe in the next loop + // if the property is changed on the next entry. + if (aEntries[i].mProperty == aEntries[i + 1].mProperty && + aEntries[i].mOffset == aEntries[i + 1].mOffset && + aEntries[i].mOffset != 1.0f && aEntries[i].mOffset != 0.0f) { + ++i; + continue; + } + + // No keyframe for this property at offset 1. + if (aEntries[i].mProperty != aEntries[i + 1].mProperty && + aEntries[i].mOffset != 1.0f) { + HandleMissingFinalKeyframe(aResult, aEntries[i], animationProperty); + // Move on to new property. + animationProperty = nullptr; + ++i; + continue; + } + + // Starting from i + 1, determine the next [i, j] interval from which to + // generate a segment. Basically, j is i + 1, but there are some special + // cases for offset 0 and 1, so we need to handle them specifically. + // Note: From this moment, we make sure [i + 1] is valid and + // there must be an initial entry (i.e. mOffset = 0.0) and + // a final entry (i.e. mOffset = 1.0). Besides, all the entries + // with the same offsets except for initial/final ones are filtered + // out already. + size_t j = i + 1; + if (aEntries[i].mOffset == 0.0f && aEntries[i + 1].mOffset == 0.0f) { + // We need to generate an initial zero-length segment. + MOZ_ASSERT(aEntries[i].mProperty == aEntries[i + 1].mProperty); + while (j + 1 < n && aEntries[j + 1].mOffset == 0.0f && + aEntries[j + 1].mProperty == aEntries[j].mProperty) { + ++j; + } + } else if (aEntries[i].mOffset == 1.0f) { + if (aEntries[i + 1].mOffset == 1.0f && + aEntries[i + 1].mProperty == aEntries[i].mProperty) { + // We need to generate a final zero-length segment. + while (j + 1 < n && aEntries[j + 1].mOffset == 1.0f && + aEntries[j + 1].mProperty == aEntries[j].mProperty) { + ++j; + } + } else { + // New property. + MOZ_ASSERT(aEntries[i].mProperty != aEntries[i + 1].mProperty); + animationProperty = nullptr; + ++i; + continue; + } + } + + // If we've moved on to a new property, create a new AnimationProperty + // to insert segments into. + if (aEntries[i].mProperty != lastProperty) { + MOZ_ASSERT(aEntries[i].mOffset == 0.0f); + MOZ_ASSERT(!animationProperty); + animationProperty = aResult.AppendElement(); + animationProperty->mProperty = aEntries[i].mProperty; + lastProperty = aEntries[i].mProperty; + } + + MOZ_ASSERT(animationProperty, "animationProperty should be valid pointer."); + + // Now generate the segment. + AnimationPropertySegment* segment = + animationProperty->mSegments.AppendElement(); + segment->mFromKey = aEntries[i].mOffset; + segment->mToKey = aEntries[j].mOffset; + segment->mFromValue = aEntries[i].mValue; + segment->mToValue = aEntries[j].mValue; + segment->mTimingFunction = aEntries[i].mTimingFunction; + segment->mFromComposite = aEntries[i].mComposite; + segment->mToComposite = aEntries[j].mComposite; + + i = j; + } +} + +/** + * Converts a JS object representing a property-indexed keyframe into + * an array of Keyframe objects. + * + * @param aCx The JSContext for |aValue|. + * @param aDocument The document to use when parsing CSS properties. + * @param aValue The JS object. + * @param aResult The array into which the resulting AnimationProperty + * objects will be appended. + * @param aRv Out param to store any errors thrown by this function. + */ +static void GetKeyframeListFromPropertyIndexedKeyframe( + JSContext* aCx, dom::Document* aDocument, JS::Handle<JS::Value> aValue, + nsTArray<Keyframe>& aResult, ErrorResult& aRv) { + MOZ_ASSERT(aValue.isObject()); + MOZ_ASSERT(aResult.IsEmpty()); + MOZ_ASSERT(!aRv.Failed()); + + // Convert the object to a property-indexed keyframe dictionary to + // get its explicit dictionary members. + dom::binding_detail::FastBasePropertyIndexedKeyframe keyframeDict; + // XXXbz Pass in the method name from callers and set up a BindingCallContext? + if (!keyframeDict.Init(aCx, aValue, "BasePropertyIndexedKeyframe argument")) { + aRv.Throw(NS_ERROR_FAILURE); + return; + } + + // Get all the property--value-list pairs off the object. + JS::Rooted<JSObject*> object(aCx, &aValue.toObject()); + nsTArray<PropertyValuesPair> propertyValuesPairs; + if (!GetPropertyValuesPairs(aCx, object, ListAllowance::eAllow, + propertyValuesPairs)) { + aRv.Throw(NS_ERROR_FAILURE); + return; + } + + // Create a set of keyframes for each property. + nsClassHashtable<nsFloatHashKey, Keyframe> processedKeyframes; + for (const PropertyValuesPair& pair : propertyValuesPairs) { + size_t count = pair.mValues.Length(); + if (count == 0) { + // No animation values for this property. + continue; + } + + // If we only have one value, we should animate from the underlying value + // but not if the pref for supporting implicit keyframes is disabled. + if (!StaticPrefs::dom_animations_api_implicit_keyframes_enabled() && + count == 1) { + aRv.Throw(NS_ERROR_DOM_ANIM_MISSING_PROPS_ERR); + return; + } + + size_t n = pair.mValues.Length() - 1; + size_t i = 0; + + for (const nsCString& stringValue : pair.mValues) { + // For single-valued lists, the single value should be added to a + // keyframe with offset 1. + double offset = n ? i++ / double(n) : 1; + Keyframe* keyframe = processedKeyframes.LookupOrAdd(offset); + if (keyframe->mPropertyValues.IsEmpty()) { + keyframe->mComputedOffset = offset; + } + + Maybe<PropertyValuePair> valuePair = + MakePropertyValuePair(pair.mProperty, stringValue, aDocument); + if (!valuePair) { + continue; + } + keyframe->mPropertyValues.AppendElement(std::move(valuePair.ref())); + } + } + + aResult.SetCapacity(processedKeyframes.Count()); + for (auto iter = processedKeyframes.Iter(); !iter.Done(); iter.Next()) { + aResult.AppendElement(std::move(*iter.UserData())); + } + + aResult.Sort(ComputedOffsetComparator()); + + // Fill in any specified offsets + // + // This corresponds to step 5, "Otherwise," branch, substeps 5-6 of + // https://drafts.csswg.org/web-animations/#processing-a-keyframes-argument + const FallibleTArray<Nullable<double>>* offsets = nullptr; + AutoTArray<Nullable<double>, 1> singleOffset; + auto& offset = keyframeDict.mOffset; + if (offset.IsDouble()) { + singleOffset.AppendElement(offset.GetAsDouble()); + // dom::Sequence is a fallible but AutoTArray is infallible and we need to + // point to one or the other. Fortunately, fallible and infallible array + // types can be implicitly converted provided they are const. + const FallibleTArray<Nullable<double>>& asFallibleArray = singleOffset; + offsets = &asFallibleArray; + } else if (offset.IsDoubleOrNullSequence()) { + offsets = &offset.GetAsDoubleOrNullSequence(); + } + // If offset.IsNull() is true, then we want to leave the mOffset member of + // each keyframe with its initialized value of null. By leaving |offsets| + // as nullptr here, we skip updating mOffset below. + + size_t offsetsToFill = + offsets ? std::min(offsets->Length(), aResult.Length()) : 0; + for (size_t i = 0; i < offsetsToFill; i++) { + if (!offsets->ElementAt(i).IsNull()) { + aResult[i].mOffset.emplace(offsets->ElementAt(i).Value()); + } + } + + // Check that the keyframes are loosely sorted and that any specified offsets + // are between 0.0 and 1.0 inclusive. + // + // This corresponds to steps 6-7 of + // https://drafts.csswg.org/web-animations/#processing-a-keyframes-argument + // + // In the spec, TypeErrors arising from invalid offsets and easings are thrown + // at the end of the procedure since it assumes we initially store easing + // values as strings and then later parse them. + // + // However, we will parse easing members immediately when we process them + // below. In order to maintain the relative order in which TypeErrors are + // thrown according to the spec, namely exceptions arising from invalid + // offsets are thrown before exceptions arising from invalid easings, we check + // the offsets here. + if (!HasValidOffsets(aResult)) { + aResult.Clear(); + aRv.ThrowTypeError<dom::MSG_INVALID_KEYFRAME_OFFSETS>(); + return; + } + + // Fill in any easings. + // + // This corresponds to step 5, "Otherwise," branch, substeps 7-11 of + // https://drafts.csswg.org/web-animations/#processing-a-keyframes-argument + FallibleTArray<Maybe<ComputedTimingFunction>> easings; + auto parseAndAppendEasing = [&](const nsACString& easingString, + ErrorResult& aRv) { + auto easing = TimingParams::ParseEasing(easingString, aRv); + if (!aRv.Failed() && !easings.AppendElement(std::move(easing), fallible)) { + aRv.Throw(NS_ERROR_OUT_OF_MEMORY); + } + }; + + auto& easing = keyframeDict.mEasing; + if (easing.IsUTF8String()) { + parseAndAppendEasing(easing.GetAsUTF8String(), aRv); + if (aRv.Failed()) { + aResult.Clear(); + return; + } + } else { + for (const auto& easingString : easing.GetAsUTF8StringSequence()) { + parseAndAppendEasing(easingString, aRv); + if (aRv.Failed()) { + aResult.Clear(); + return; + } + } + } + + // If |easings| is empty, then we are supposed to fill it in with the value + // "linear" and then repeat the list as necessary. + // + // However, for Keyframe.mTimingFunction we represent "linear" as a None + // value. Since we have not assigned 'mTimingFunction' for any of the + // keyframes in |aResult| they will already have their initial None value + // (i.e. linear). As a result, if |easings| is empty, we don't need to do + // anything. + if (!easings.IsEmpty()) { + for (size_t i = 0; i < aResult.Length(); i++) { + aResult[i].mTimingFunction = easings[i % easings.Length()]; + } + } + + // Fill in any composite operations. + // + // This corresponds to step 5, "Otherwise," branch, substep 12 of + // https://drafts.csswg.org/web-animations/#processing-a-keyframes-argument + if (StaticPrefs::dom_animations_api_compositing_enabled()) { + const FallibleTArray<dom::CompositeOperationOrAuto>* compositeOps = nullptr; + AutoTArray<dom::CompositeOperationOrAuto, 1> singleCompositeOp; + auto& composite = keyframeDict.mComposite; + if (composite.IsCompositeOperationOrAuto()) { + singleCompositeOp.AppendElement( + composite.GetAsCompositeOperationOrAuto()); + const FallibleTArray<dom::CompositeOperationOrAuto>& asFallibleArray = + singleCompositeOp; + compositeOps = &asFallibleArray; + } else if (composite.IsCompositeOperationOrAutoSequence()) { + compositeOps = &composite.GetAsCompositeOperationOrAutoSequence(); + } + + // Fill in and repeat as needed. + if (compositeOps && !compositeOps->IsEmpty()) { + size_t length = compositeOps->Length(); + for (size_t i = 0; i < aResult.Length(); i++) { + aResult[i].mComposite = compositeOps->ElementAt(i % length); + } + } + } +} + +/** + * Returns true if the supplied set of keyframes has keyframe values for + * any property for which it does not also supply a value for the 0% and 100% + * offsets. The check is not entirely accurate but should detect most common + * cases. + * + * @param aKeyframes The set of keyframes to analyze. + * @param aDocument The document to use when parsing keyframes so we can + * try to detect where we have an invalid value at 0%/100%. + */ +static bool HasImplicitKeyframeValues(const nsTArray<Keyframe>& aKeyframes, + dom::Document* aDocument) { + // We are looking to see if that every property referenced in |aKeyframes| + // has a valid property at offset 0.0 and 1.0. The check as to whether a + // property is valid or not, however, is not precise. We only check if the + // property can be parsed, NOT whether it can also be converted to a + // StyleAnimationValue since doing that requires a target element bound to + // a document which we might not always have at the point where we want to + // perform this check. + // + // This is only a temporary measure until we ship implicit keyframes and + // remove the corresponding pref. + // So as long as this check catches most cases, and we don't do anything + // horrible in one of the cases we can't detect, it should be sufficient. + + nsCSSPropertyIDSet properties; // All properties encountered. + nsCSSPropertyIDSet propertiesWithFromValue; // Those with a defined 0% value. + nsCSSPropertyIDSet propertiesWithToValue; // Those with a defined 100% value. + + auto addToPropertySets = [&](nsCSSPropertyID aProperty, double aOffset) { + properties.AddProperty(aProperty); + if (aOffset == 0.0) { + propertiesWithFromValue.AddProperty(aProperty); + } else if (aOffset == 1.0) { + propertiesWithToValue.AddProperty(aProperty); + } + }; + + for (size_t i = 0, len = aKeyframes.Length(); i < len; i++) { + const Keyframe& frame = aKeyframes[i]; + + // We won't have called DistributeKeyframes when this is called so + // we can't use frame.mComputedOffset. Instead we do a rough version + // of that algorithm that substitutes null offsets with 0.0 for the first + // frame, 1.0 for the last frame, and 0.5 for everything else. + double computedOffset = i == len - 1 ? 1.0 : i == 0 ? 0.0 : 0.5; + double offsetToUse = frame.mOffset ? frame.mOffset.value() : computedOffset; + + for (const PropertyValuePair& pair : frame.mPropertyValues) { + if (nsCSSProps::IsShorthand(pair.mProperty)) { + MOZ_ASSERT(pair.mServoDeclarationBlock); + CSSPROPS_FOR_SHORTHAND_SUBPROPERTIES(prop, pair.mProperty, + CSSEnabledState::ForAllContent) { + addToPropertySets(*prop, offsetToUse); + } + } else { + addToPropertySets(pair.mProperty, offsetToUse); + } + } + } + + return !propertiesWithFromValue.Equals(properties) || + !propertiesWithToValue.Equals(properties); +} + +/** + * Distribute the offsets of all keyframes in between the endpoints of the + * given range. + * + * @param aRange The sequence of keyframes between whose endpoints we should + * distribute offsets. + */ +static void DistributeRange(const Range<Keyframe>& aRange) { + const Range<Keyframe> rangeToAdjust = + Range<Keyframe>(aRange.begin() + 1, aRange.end() - 1); + const size_t n = aRange.length() - 1; + const double startOffset = aRange[0].mComputedOffset; + const double diffOffset = aRange[n].mComputedOffset - startOffset; + for (auto iter = rangeToAdjust.begin(); iter != rangeToAdjust.end(); ++iter) { + size_t index = iter - aRange.begin(); + iter->mComputedOffset = startOffset + double(index) / n * diffOffset; + } +} + +} // namespace mozilla |