Web Animations: Extract an API for servicing animations

Source/core/animation/DocumentAnimations.cpp

+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
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+ * in the documentation and/or other materials provided with the
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+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "core/animation/DocumentAnimations.h"
+
+#include "core/animation/ActiveAnimations.h"
+#include "core/animation/AnimationClock.h"
+#include "core/animation/DocumentTimeline.h"
+#include "core/dom/Document.h"
+#include "core/dom/Element.h"
+#include "core/dom/Node.h"
+#include "core/frame/Frame.h"
+#include "core/frame/FrameView.h"
+#include "core/rendering/RenderLayerCompositor.h"
+#include "core/rendering/RenderView.h"
+
+namespace WebCore {
+
+namespace {
+
+void updateAnimationTiming(Document& document, double monotonicAnimationStartTime)
+{
+    document.animationClock().updateTime(monotonicAnimationStartTime);
+    bool didTriggerStyleRecalc = document.timeline()->serviceAnimations();
+    didTriggerStyleRecalc |= document.transitionTimeline()->serviceAnimations();
+    if (!didTriggerStyleRecalc)
+        document.animationClock().unfreeze();
+}
+
+void dispatchAnimationEvents(Document& document)
+{
+    document.timeline()->dispatchEvents();
+    document.transitionTimeline()->dispatchEvents();
+}
+
+} // namespace
+
+void DocumentAnimations::serviceOnAnimationFrame(Document& document, double monotonicAnimationStartTime)
+{
+    if (!RuntimeEnabledFeatures::webAnimationsEnabled())
+        return;
+
+    // FIXME: This shouldn't be required, but when running under content_shell (--dump-render-tree
+    // without threaded compositing) the compositing update may never happen.

[Steve Block, 2013/11/20 00:36:16]

I don't understand this - can you expand a little?

[dstockwell, 2013/11/20 00:49:16]

Shawn sent a PSA to blink-dev about this, but basically a compositing update is
deferred until the compositor actually needs it. In the case of typical layout
tests this never happens unless they call testRunner.display() or
internals.forceCompositingUpdate()

+    document.cssPendingAnimations().startPendingAnimationsAfterCompositingUpdate();
+
+    // FIXME: Animation events for newly started CSS Animations should be fired
+    // asynchronously after the style recalc that triggered them. For now we fire
+    // them here (a frame late) so that they at least apply against the correct
+    // animation state.
+    dispatchAnimationEvents(document);
+    updateAnimationTiming(document, monotonicAnimationStartTime);
+    dispatchAnimationEvents(document);
+}
+
+void DocumentAnimations::serviceBeforeGetComputedStyle(Node& node, CSSPropertyID property)
+{
+    if (!RuntimeEnabledFeatures::webAnimationsEnabled())
+        return;
+
+    if (node.isElementNode()) {
+        const Element& element = toElement(node);
+        if (const ActiveAnimations* activeAnimations = element.activeAnimations()) {
+            if (activeAnimations->hasActiveAnimationsOnCompositor(property))
+                updateAnimationTiming(element.document(), monotonicallyIncreasingTime());
+        }
+    }
+
+}
+
+void DocumentAnimations::serviceAfterStyleRecalc(Document& document)
+{
+    if (!RuntimeEnabledFeatures::webAnimationsEnabled())
+        return;
+
+    document.cssPendingAnimations().startPendingAnimationsAfterStyleRecalc();
+    document.animationClock().unfreeze();
+}
+
+void DocumentAnimations::serviceAfterCompositingUpdate(FrameView& frameView)
+{
+    if (!RuntimeEnabledFeatures::webAnimationsCSSEnabled())
+        return;
+
+    for (RefPtr<Frame> frame = &frameView.frame(); frame; frame = frame->tree().traverseNext())
+        frame->document()->cssPendingAnimations().startPendingAnimationsAfterCompositingUpdate();
+}
+
+} // namespace WebCore