third_party/WebKit/Source/core/animation/CompositorPendingAnimations.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
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * 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 "core/animation/CompositorPendingAnimations.h"

#include "core/animation/AnimationTimeline.h"
#include "core/animation/KeyframeEffect.h"
#include "core/dom/Document.h"
#include "core/frame/FrameView.h"
#include "core/page/Page.h"
#include "platform/instrumentation/tracing/TraceEvent.h"

namespace blink {

void CompositorPendingAnimations::add(Animation* animation) {
  DCHECK(animation);
  DCHECK_EQ(m_pending.find(animation), kNotFound);
  m_pending.push_back(animation);

  Document* document = animation->timeline()->document();
  if (document->view())
    document->view()->scheduleAnimation();

  bool visible = document->page() && document->page()->isPageVisible();
  if (!visible && !m_timer.isActive()) {
    m_timer.startOneShot(0, BLINK_FROM_HERE);
  }
}

bool CompositorPendingAnimations::update(bool startOnCompositor) {
  HeapVector<Member<Animation>> waitingForStartTime;
  bool startedSynchronizedOnCompositor = false;

  HeapVector<Member<Animation>> animations;
  HeapVector<Member<Animation>> deferred;
  animations.swap(m_pending);
  int compositorGroup = ++m_compositorGroup;
  while (compositorGroup == 0 || compositorGroup == 1) {
    // Wrap around, skipping 0, 1.
    // * 0 is reserved for automatic assignment
    // * 1 is used for animations with a specified start time
    compositorGroup = ++m_compositorGroup;
  }

  for (auto& animation : animations) {
    bool hadCompositorAnimation = animation->hasActiveAnimationsOnCompositor();
    // Animations with a start time do not participate in compositor start-time
    // grouping.
    if (animation->preCommit(animation->hasStartTime() ? 1 : compositorGroup,
                             startOnCompositor)) {
      if (animation->hasActiveAnimationsOnCompositor() &&
          !hadCompositorAnimation) {
        startedSynchronizedOnCompositor = true;
      }

      if (animation->playing() && !animation->hasStartTime() &&
          animation->timeline() && animation->timeline()->isActive()) {
        waitingForStartTime.push_back(animation.get());
      }
    } else {
      deferred.push_back(animation);
    }
  }

  // If any synchronized animations were started on the compositor, all
  // remaining synchronized animations need to wait for the synchronized
  // start time. Otherwise they may start immediately.
  if (startedSynchronizedOnCompositor) {
    for (auto& animation : waitingForStartTime) {
      if (!animation->hasStartTime()) {
        m_waitingForCompositorAnimationStart.push_back(animation);
      }
    }
  } else {
    for (auto& animation : waitingForStartTime) {
      if (!animation->hasStartTime()) {
        animation->notifyCompositorStartTime(
            animation->timeline()->currentTimeInternal());
      }
    }
  }

  // FIXME: The postCommit should happen *after* the commit, not before.
  for (auto& animation : animations)
    animation->postCommit(animation->timeline()->currentTimeInternal());

  DCHECK(m_pending.isEmpty());
  DCHECK(startOnCompositor || deferred.isEmpty());
  for (auto& animation : deferred)
    animation->setCompositorPending();
  DCHECK_EQ(m_pending.size(), deferred.size());

  if (startedSynchronizedOnCompositor)
    return true;

  if (m_waitingForCompositorAnimationStart.isEmpty())
    return false;

  // Check if we're still waiting for any compositor animations to start.
  for (auto& animation : m_waitingForCompositorAnimationStart) {
    if (animation->hasActiveAnimationsOnCompositor())
      return true;
  }

  // If not, go ahead and start any animations that were waiting.
  notifyCompositorAnimationStarted(monotonicallyIncreasingTime());

  DCHECK_EQ(m_pending.size(), deferred.size());
  return false;
}

void CompositorPendingAnimations::notifyCompositorAnimationStarted(
    double monotonicAnimationStartTime,
    int compositorGroup) {
  TRACE_EVENT0("blink",
               "CompositorPendingAnimations::notifyCompositorAnimationStarted");
  HeapVector<Member<Animation>> animations;
  animations.swap(m_waitingForCompositorAnimationStart);

  for (auto animation : animations) {
    if (animation->hasStartTime() ||
        animation->playStateInternal() != Animation::Pending ||
        !animation->timeline() || !animation->timeline()->isActive()) {
      // Already started or no longer relevant.
      continue;
    }
    if (compositorGroup && animation->compositorGroup() != compositorGroup) {
      // Still waiting.
      m_waitingForCompositorAnimationStart.push_back(animation);
      continue;
    }
    animation->notifyCompositorStartTime(monotonicAnimationStartTime -
                                         animation->timeline()->zeroTime());
  }
}

DEFINE_TRACE(CompositorPendingAnimations) {
  visitor->trace(m_pending);
  visitor->trace(m_waitingForCompositorAnimationStart);
}

}  // namespace blink