third_party/blink/renderer/platform/graphics/paint/property_tree_state.cc

// 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 "third_party/blink/renderer/platform/graphics/paint/property_tree_state.h"

#include <memory>

namespace blink {

const PropertyTreeState& PropertyTreeState::Root() {
  DEFINE_STATIC_LOCAL(
      PropertyTreeState, root,
      (&TransformPaintPropertyNode::Root(), &ClipPaintPropertyNode::Root(),
       &EffectPaintPropertyNode::Root()));
  return root;
}

const CompositorElementId PropertyTreeState::GetCompositorElementId(
    const CompositorElementIdSet& element_ids) const {
  // The effect or transform nodes could have a compositor element id. The order
  // doesn't matter as the element id should be the same on all that have a
  // non-default CompositorElementId.
  //
  // Note that PropertyTreeState acts as a context that accumulates state as we
  // traverse the tree building layers. This means that we could see a
  // compositor element id 'A' for a parent layer in conjunction with a
  // compositor element id 'B' for a child layer. To preserve uniqueness of
  // element ids, then, we check for presence in the |element_ids| set (which
  // represents element ids already previously attached to a layer). This is an
  // interim step while we pursue broader rework of animation subsystem noted in
  // http://crbug.com/709137.
  if (Effect()->GetCompositorElementId() &&
      !element_ids.Contains(Effect()->GetCompositorElementId()))
    return Effect()->GetCompositorElementId();
  if (Transform()->GetCompositorElementId() &&
      !element_ids.Contains(Transform()->GetCompositorElementId()))
    return Transform()->GetCompositorElementId();
  return CompositorElementId();
}

String PropertyTreeState::ToString() const {
  return String::Format("t:%p c:%p e:%p", Transform(), Clip(), Effect());
}

#if DCHECK_IS_ON()

String PropertyTreeState::ToTreeString() const {
  return "transform:\n" + (Transform() ? Transform()->ToTreeString() : "null") +
         "\nclip:\n" + (Clip() ? Clip()->ToTreeString() : "null") +
         "\neffect:\n" + (Effect() ? Effect()->ToTreeString() : "null");
}

#endif

size_t PropertyTreeState::CacheMemoryUsageInBytes() const {
  return Clip()->CacheMemoryUsageInBytes() +
         Transform()->CacheMemoryUsageInBytes();
}

}  // namespace blink