compositor-worker: cc->blink mutation plumbing

third_party/WebKit/Source/core/animation/CustomCompositorAnimations.cpp

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "CustomCompositorAnimations.h"
+
+#include "core/animation/Animation.h"
+#include "core/animation/AnimationTimeline.h"
+#include "core/animation/KeyframeEffect.h"
+#include "core/animation/KeyframeEffectModel.h"
+#include "core/animation/animatable/AnimatableDouble.h"
+#include "core/animation/animatable/AnimatableTransform.h"
+#include "core/animation/animatable/AnimatableValue.h"
+#include "platform/TraceEvent.h"
+#include "platform/graphics/CompositorMutation.h"
+#include "platform/transforms/Matrix3DTransformOperation.h"
+#include "platform/transforms/MatrixTransformOperation.h"
+#include "platform/transforms/TransformOperations.h"
+
+namespace blink {
+
+namespace {
+
+// Create keyframe effect with zero duration, fill mode forward, and two key
+// frames with same value. This corresponding animation is always running and by
+// updating the key frames we are able to control the applied value.
+static KeyframeEffect* createInfiniteKeyFrameEffect(Element& element, CSSPropertyID propertyId, PassRefPtr<AnimatableValue> value)
+{
+    AnimatableValueKeyframeVector keyframes(2);
+    keyframes[0] = AnimatableValueKeyframe::create();
+    keyframes[0]->setOffset(0.0);
+    keyframes[0]->setPropertyValue(propertyId, value.get());
+    keyframes[1] = AnimatableValueKeyframe::create();
+    keyframes[1]->setOffset(1.0);
+    keyframes[1]->setPropertyValue(propertyId, value.get());
+    keyframes[1]->setComposite(EffectModel::CompositeReplace);
+
+    Timing timing;
+    timing.iterationDuration = 0;
+    timing.fillMode = Timing::FillModeForwards;
+
+    AnimatableValueKeyframeEffectModel* effectModel = AnimatableValueKeyframeEffectModel::create(keyframes);
+    return KeyframeEffect::create(&element, effectModel, timing);
+}
+
+static KeyframeEffect* updateInfiniteKeyframeEffect(const KeyframeEffect& keyframeEffect, CSSPropertyID propertyId, PassRefPtr<AnimatableValue> value)
+{
+    const KeyframeVector& oldFrames = toAnimatableValueKeyframeEffectModel(keyframeEffect.model())->getFrames();
+    AnimatableValueKeyframeVector keyframes(2);
+    keyframes[0] = toAnimatableValueKeyframe(oldFrames[0]->clone().get());
+    keyframes[1] = toAnimatableValueKeyframe(oldFrames[1]->clone().get());
+    keyframes[0]->setPropertyValue(propertyId, value.get());
+    keyframes[1]->setPropertyValue(propertyId, value.get());
+
+    AnimatableValueKeyframeEffectModel* effectModel = AnimatableValueKeyframeEffectModel::create(keyframes);
+    return KeyframeEffect::create(keyframeEffect.target(), effectModel, keyframeEffect.specifiedTiming());
+}
+
+static Animation* createOrUpdateAnimation(Animation* animation, Element& element, CSSPropertyID propertyId, PassRefPtr<AnimatableValue> newValue)
+{
+    if (!animation) {
+        KeyframeEffect* keyframeEffect = createInfiniteKeyFrameEffect(element, propertyId, newValue);
+        return element.document().timeline().play(keyframeEffect);
+    }
+    KeyframeEffect* keyframeEffect = updateInfiniteKeyframeEffect(*toKeyframeEffect(animation->effect()), propertyId, newValue);
+    animation->setEffect(keyframeEffect);
+    return animation;
+}
+
+} // namespace
+
+void CustomCompositorAnimations::applyUpdate(Element& element, const CompositorMutation& mutation)
+{
+    TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("compositor-worker"), "CustomCompositorAnimations::applyUpdate");
+
+    if (mutation.isOpacityMutated()) {
+        RefPtr<AnimatableValue> animatableValue = AnimatableDouble::create(mutation.opacity());
+        m_animation = createOrUpdateAnimation(m_animation, element, CSSPropertyOpacity, animatableValue.release());
+    }
+    if (mutation.isTransformMutated()) {
+        TransformOperations ops;
+        ops.operations().append(Matrix3DTransformOperation::create(TransformationMatrix(mutation.transform())));
+        RefPtr<AnimatableValue> animatableValue = AnimatableTransform::create(ops, 1);
+        m_animation = createOrUpdateAnimation(m_animation, element, CSSPropertyTransform, animatableValue.release());
+    }
+}
+
+} // namespace blink