cc/trees/property_tree.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include <set>
   6 #include <vector>
   7
   8 #include "base/logging.h"
   9 #include "cc/base/math_util.h"
  10 #include "cc/trees/property_tree.h"
  11
  12 namespace cc {
  13
  14 template <typename T>
  15 PropertyTree<T>::PropertyTree()
  16     : needs_update_(false) {
  17   nodes_.push_back(T());
  18   back()->id = 0;
  19   back()->parent_id = -1;
  20 }
  21
  22 template <typename T>
  23 PropertyTree<T>::~PropertyTree() {
  24 }
  25
  26 TransformTree::TransformTree() : source_to_parent_updates_allowed_(true) {}
  27
  28 TransformTree::~TransformTree() {
  29 }
  30
  31 template <typename T>
  32 int PropertyTree<T>::Insert(const T& tree_node, int parent_id) {
  33   DCHECK_GT(nodes_.size(), 0u);
  34   nodes_.push_back(tree_node);
  35   T& node = nodes_.back();
  36   node.parent_id = parent_id;
  37   node.id = static_cast<int>(nodes_.size()) - 1;
  38   return node.id;
  39 }
  40
  41 template <typename T>
  42 void PropertyTree<T>::clear() {
  43   nodes_.clear();
  44   nodes_.push_back(T());
  45   back()->id = 0;
  46   back()->parent_id = -1;
  47 }
  48
  49 template class PropertyTree<TransformNode>;
  50 template class PropertyTree<ClipNode>;
  51 template class PropertyTree<EffectNode>;
  52
  53 TransformNodeData::TransformNodeData()
  54     : target_id(-1),
  55       content_target_id(-1),
  56       source_node_id(-1),
  57       needs_local_transform_update(true),
  58       is_invertible(true),
  59       ancestors_are_invertible(true),
  60       is_animated(false),
  61       to_screen_is_animated(false),
  62       has_only_translation_animations(true),
  63       to_screen_has_scale_animation(false),
  64       flattens_inherited_transform(false),
  65       node_and_ancestors_are_flat(true),
  66       node_and_ancestors_have_only_integer_translation(true),
  67       scrolls(false),
  68       needs_sublayer_scale(false),
  69       affected_by_inner_viewport_bounds_delta_x(false),
  70       affected_by_inner_viewport_bounds_delta_y(false),
  71       affected_by_outer_viewport_bounds_delta_x(false),
  72       affected_by_outer_viewport_bounds_delta_y(false),
  73       layer_scale_factor(1.0f),
  74       post_local_scale_factor(1.0f),
  75       local_maximum_animation_target_scale(0.f),
  76       local_starting_animation_scale(0.f),
  77       combined_maximum_animation_target_scale(0.f),
  78       combined_starting_animation_scale(0.f) {}
  79
  80 TransformNodeData::~TransformNodeData() {
  81 }
  82
  83 void TransformNodeData::update_pre_local_transform(
  84     const gfx::Point3F& transform_origin) {
  85   pre_local.MakeIdentity();
  86   pre_local.Translate3d(-transform_origin.x(), -transform_origin.y(),
  87                         -transform_origin.z());
  88 }
  89
  90 void TransformNodeData::update_post_local_transform(
  91     const gfx::PointF& position,
  92     const gfx::Point3F& transform_origin) {
  93   post_local.MakeIdentity();
  94   post_local.Scale(post_local_scale_factor, post_local_scale_factor);
  95   post_local.Translate3d(
  96       position.x() + source_offset.x() + transform_origin.x(),
  97       position.y() + source_offset.y() + transform_origin.y(),
  98       transform_origin.z());
  99 }
 100
 101 ClipNodeData::ClipNodeData()
 102     : transform_id(-1),
 103       target_id(-1),
 104       inherit_parent_target_space_clip(false),
 105       requires_tight_clip_rect(true),
 106       render_surface_is_clipped(false) {}
 107
 108 EffectNodeData::EffectNodeData() : opacity(1.f), screen_space_opacity(1.f) {}
 109
 110 void TransformTree::clear() {
 111   PropertyTree<TransformNode>::clear();
 112
 113   nodes_affected_by_inner_viewport_bounds_delta_.clear();
 114   nodes_affected_by_outer_viewport_bounds_delta_.clear();
 115 }
 116
 117 bool TransformTree::ComputeTransform(int source_id,
 118                                      int dest_id,
 119                                      gfx::Transform* transform) const {
 120   transform->MakeIdentity();
 121
 122   if (source_id == dest_id)
 123     return true;
 124
 125   if (source_id > dest_id) {
 126     return CombineTransformsBetween(source_id, dest_id, transform);
 127   }
 128
 129   return CombineInversesBetween(source_id, dest_id, transform);
 130 }
 131
 132 bool TransformTree::ComputeTransformWithDestinationSublayerScale(
 133     int source_id,
 134     int dest_id,
 135     gfx::Transform* transform) const {
 136   bool success = ComputeTransform(source_id, dest_id, transform);
 137
 138   const TransformNode* dest_node = Node(dest_id);
 139   if (!dest_node->data.needs_sublayer_scale)
 140     return success;
 141
 142   transform->matrix().postScale(dest_node->data.sublayer_scale.x(),
 143                                 dest_node->data.sublayer_scale.y(), 1.f);
 144   return success;
 145 }
 146
 147 bool TransformTree::ComputeTransformWithSourceSublayerScale(
 148     int source_id,
 149     int dest_id,
 150     gfx::Transform* transform) const {
 151   bool success = ComputeTransform(source_id, dest_id, transform);
 152
 153   const TransformNode* source_node = Node(source_id);
 154   if (!source_node->data.needs_sublayer_scale)
 155     return success;
 156
 157   if (source_node->data.sublayer_scale.x() == 0 ||
 158       source_node->data.sublayer_scale.y() == 0)
 159     return false;
 160
 161   transform->Scale(1.f / source_node->data.sublayer_scale.x(),
 162                    1.f / source_node->data.sublayer_scale.y());
 163   return success;
 164 }
 165
 166 bool TransformTree::Are2DAxisAligned(int source_id, int dest_id) const {
 167   gfx::Transform transform;
 168   return ComputeTransform(source_id, dest_id, &transform) &&
 169          transform.Preserves2dAxisAlignment();
 170 }
 171
 172 bool TransformTree::NeedsSourceToParentUpdate(TransformNode* node) {
 173   return (source_to_parent_updates_allowed() &&
 174           node->parent_id != node->data.source_node_id);
 175 }
 176
 177 void TransformTree::UpdateTransforms(int id) {
 178   TransformNode* node = Node(id);
 179   TransformNode* parent_node = parent(node);
 180   TransformNode* target_node = Node(node->data.target_id);
 181   if (node->data.needs_local_transform_update ||
 182       NeedsSourceToParentUpdate(node))
 183     UpdateLocalTransform(node);
 184   UpdateScreenSpaceTransform(node, parent_node, target_node);
 185   UpdateSublayerScale(node);
 186   UpdateTargetSpaceTransform(node, target_node);
 187   UpdateAnimationProperties(node, parent_node);
 188   UpdateSnapping(node);
 189   UpdateNodeAndAncestorsHaveIntegerTranslations(node, parent_node);
 190 }
 191
 192 bool TransformTree::IsDescendant(int desc_id, int source_id) const {
 193   while (desc_id != source_id) {
 194     if (desc_id < 0)
 195       return false;
 196     desc_id = Node(desc_id)->parent_id;
 197   }
 198   return true;
 199 }
 200
 201 bool TransformTree::CombineTransformsBetween(int source_id,
 202                                              int dest_id,
 203                                              gfx::Transform* transform) const {
 204   DCHECK(source_id > dest_id);
 205   const TransformNode* current = Node(source_id);
 206   const TransformNode* dest = Node(dest_id);
 207   // Combine transforms to and from the screen when possible. Since flattening
 208   // is a non-linear operation, we cannot use this approach when there is
 209   // non-trivial flattening between the source and destination nodes. For
 210   // example, consider the tree R->A->B->C, where B flattens its inherited
 211   // transform, and A has a non-flat transform. Suppose C is the source and A is
 212   // the destination. The expected result is C * B. But C's to_screen
 213   // transform is C * B * flattened(A * R), and A's from_screen transform is
 214   // R^{-1} * A^{-1}. If at least one of A and R isn't flat, the inverse of
 215   // flattened(A * R) won't be R^{-1} * A{-1}, so multiplying C's to_screen and
 216   // A's from_screen will not produce the correct result.
 217   if (!dest || (dest->data.ancestors_are_invertible &&
 218                 dest->data.node_and_ancestors_are_flat)) {
 219     transform->ConcatTransform(current->data.to_screen);
 220     if (dest)
 221       transform->ConcatTransform(dest->data.from_screen);
 222     return true;
 223   }
 224
 225   // Flattening is defined in a way that requires it to be applied while
 226   // traversing downward in the tree. We first identify nodes that are on the
 227   // path from the source to the destination (this is traversing upward), and
 228   // then we visit these nodes in reverse order, flattening as needed. We
 229   // early-out if we get to a node whose target node is the destination, since
 230   // we can then re-use the target space transform stored at that node. However,
 231   // we cannot re-use a stored target space transform if the destination has a
 232   // zero sublayer scale, since stored target space transforms have sublayer
 233   // scale baked in, but we need to compute an unscaled transform.
 234   std::vector<int> source_to_destination;
 235   source_to_destination.push_back(current->id);
 236   current = parent(current);
 237   bool destination_has_non_zero_sublayer_scale =
 238       dest->data.sublayer_scale.x() != 0.f &&
 239       dest->data.sublayer_scale.y() != 0.f;
 240   DCHECK(destination_has_non_zero_sublayer_scale ||
 241          !dest->data.ancestors_are_invertible);
 242   for (; current && current->id > dest_id; current = parent(current)) {
 243     if (destination_has_non_zero_sublayer_scale &&
 244         current->data.target_id == dest_id &&
 245         current->data.content_target_id == dest_id)
 246       break;
 247     source_to_destination.push_back(current->id);
 248   }
 249
 250   gfx::Transform combined_transform;
 251   if (current->id > dest_id) {
 252     combined_transform = current->data.to_target;
 253     // The stored target space transform has sublayer scale baked in, but we
 254     // need the unscaled transform.
 255     combined_transform.Scale(1.0f / dest->data.sublayer_scale.x(),
 256                              1.0f / dest->data.sublayer_scale.y());
 257   } else if (current->id < dest_id) {
 258     // We have reached the lowest common ancestor of the source and destination
 259     // nodes. This case can occur when we are transforming between a node
 260     // corresponding to a fixed-position layer (or its descendant) and the node
 261     // corresponding to the layer's render target. For example, consider the
 262     // layer tree R->T->S->F where F is fixed-position, S owns a render surface,
 263     // and T has a significant transform. This will yield the following
 264     // transform tree:
 265     //    R
 266     //    |
 267     //    T
 268     //   /|
 269     //  S F
 270     // In this example, T will have id 2, S will have id 3, and F will have id
 271     // 4. When walking up the ancestor chain from F, the first node with a
 272     // smaller id than S will be T, the lowest common ancestor of these nodes.
 273     // We compute the transform from T to S here, and then from F to T in the
 274     // loop below.
 275     DCHECK(IsDescendant(dest_id, current->id));
 276     CombineInversesBetween(current->id, dest_id, &combined_transform);
 277     DCHECK(combined_transform.IsApproximatelyIdentityOrTranslation(
 278         SkDoubleToMScalar(1e-4)));
 279   }
 280
 281   size_t source_to_destination_size = source_to_destination.size();
 282   for (size_t i = 0; i < source_to_destination_size; ++i) {
 283     size_t index = source_to_destination_size - 1 - i;
 284     const TransformNode* node = Node(source_to_destination[index]);
 285     if (node->data.flattens_inherited_transform)
 286       combined_transform.FlattenTo2d();
 287     combined_transform.PreconcatTransform(node->data.to_parent);
 288   }
 289
 290   transform->ConcatTransform(combined_transform);
 291   return true;
 292 }
 293
 294 bool TransformTree::CombineInversesBetween(int source_id,
 295                                            int dest_id,
 296                                            gfx::Transform* transform) const {
 297   DCHECK(source_id < dest_id);
 298   const TransformNode* current = Node(dest_id);
 299   const TransformNode* dest = Node(source_id);
 300   // Just as in CombineTransformsBetween, we can use screen space transforms in
 301   // this computation only when there isn't any non-trivial flattening
 302   // involved.
 303   if (current->data.ancestors_are_invertible &&
 304       current->data.node_and_ancestors_are_flat) {
 305     transform->PreconcatTransform(current->data.from_screen);
 306     if (dest)
 307       transform->PreconcatTransform(dest->data.to_screen);
 308     return true;
 309   }
 310
 311   // Inverting a flattening is not equivalent to flattening an inverse. This
 312   // means we cannot, for example, use the inverse of each node's to_parent
 313   // transform, flattening where needed. Instead, we must compute the transform
 314   // from the destination to the source, with flattening, and then invert the
 315   // result.
 316   gfx::Transform dest_to_source;
 317   CombineTransformsBetween(dest_id, source_id, &dest_to_source);
 318   gfx::Transform source_to_dest;
 319   bool all_are_invertible = dest_to_source.GetInverse(&source_to_dest);
 320   transform->PreconcatTransform(source_to_dest);
 321   return all_are_invertible;
 322 }
 323
 324 void TransformTree::UpdateLocalTransform(TransformNode* node) {
 325   gfx::Transform transform = node->data.post_local;
 326   if (NeedsSourceToParentUpdate(node)) {
 327     gfx::Transform to_parent;
 328     ComputeTransform(node->data.source_node_id, node->parent_id, &to_parent);
 329     node->data.source_to_parent = to_parent.To2dTranslation();
 330   }
 331
 332   gfx::Vector2dF fixed_position_adjustment;
 333   if (node->data.affected_by_inner_viewport_bounds_delta_x)
 334     fixed_position_adjustment.set_x(inner_viewport_bounds_delta_.x());
 335   else if (node->data.affected_by_outer_viewport_bounds_delta_x)
 336     fixed_position_adjustment.set_x(outer_viewport_bounds_delta_.x());
 337
 338   if (node->data.affected_by_inner_viewport_bounds_delta_y)
 339     fixed_position_adjustment.set_y(inner_viewport_bounds_delta_.y());
 340   else if (node->data.affected_by_outer_viewport_bounds_delta_y)
 341     fixed_position_adjustment.set_y(outer_viewport_bounds_delta_.y());
 342
 343   transform.Translate(
 344       node->data.source_to_parent.x() - node->data.scroll_offset.x() +
 345           fixed_position_adjustment.x(),
 346       node->data.source_to_parent.y() - node->data.scroll_offset.y() +
 347           fixed_position_adjustment.y());
 348   transform.PreconcatTransform(node->data.local);
 349   transform.PreconcatTransform(node->data.pre_local);
 350   node->data.set_to_parent(transform);
 351   node->data.needs_local_transform_update = false;
 352 }
 353
 354 void TransformTree::UpdateScreenSpaceTransform(TransformNode* node,
 355                                                TransformNode* parent_node,
 356                                                TransformNode* target_node) {
 357   if (!parent_node) {
 358     node->data.to_screen = node->data.to_parent;
 359     node->data.ancestors_are_invertible = true;
 360     node->data.to_screen_is_animated = false;
 361     node->data.node_and_ancestors_are_flat = node->data.to_parent.IsFlat();
 362   } else {
 363     node->data.to_screen = parent_node->data.to_screen;
 364     if (node->data.flattens_inherited_transform)
 365       node->data.to_screen.FlattenTo2d();
 366     node->data.to_screen.PreconcatTransform(node->data.to_parent);
 367     node->data.ancestors_are_invertible =
 368         parent_node->data.ancestors_are_invertible;
 369     node->data.node_and_ancestors_are_flat =
 370         parent_node->data.node_and_ancestors_are_flat &&
 371         node->data.to_parent.IsFlat();
 372   }
 373
 374   if (!node->data.to_screen.GetInverse(&node->data.from_screen))
 375     node->data.ancestors_are_invertible = false;
 376 }
 377
 378 void TransformTree::UpdateSublayerScale(TransformNode* node) {
 379   // The sublayer scale depends on the screen space transform, so update it too.
 380   node->data.sublayer_scale =
 381       node->data.needs_sublayer_scale
 382           ? MathUtil::ComputeTransform2dScaleComponents(
 383                 node->data.to_screen, node->data.layer_scale_factor)
 384           : gfx::Vector2dF(1.0f, 1.0f);
 385 }
 386
 387 void TransformTree::UpdateTargetSpaceTransform(TransformNode* node,
 388                                                TransformNode* target_node) {
 389   if (node->data.needs_sublayer_scale) {
 390     node->data.to_target.MakeIdentity();
 391     node->data.to_target.Scale(node->data.sublayer_scale.x(),
 392                                node->data.sublayer_scale.y());
 393   } else {
 394     const bool target_is_root_surface = target_node->id == 1;
 395     // In order to include the root transform for the root surface, we walk up
 396     // to the root of the transform tree in ComputeTransform.
 397     int target_id = target_is_root_surface ? 0 : target_node->id;
 398     ComputeTransformWithDestinationSublayerScale(node->id, target_id,
 399                                                  &node->data.to_target);
 400   }
 401
 402   if (!node->data.to_target.GetInverse(&node->data.from_target))
 403     node->data.ancestors_are_invertible = false;
 404 }
 405
 406 void TransformTree::UpdateAnimationProperties(TransformNode* node,
 407                                               TransformNode* parent_node) {
 408   bool ancestor_is_animating = false;
 409   bool ancestor_is_animating_scale = false;
 410   float ancestor_maximum_target_scale = 0.f;
 411   float ancestor_starting_animation_scale = 0.f;
 412   if (parent_node) {
 413     ancestor_is_animating = parent_node->data.to_screen_is_animated;
 414     ancestor_is_animating_scale =
 415         parent_node->data.to_screen_has_scale_animation;
 416     ancestor_maximum_target_scale =
 417         parent_node->data.combined_maximum_animation_target_scale;
 418     ancestor_starting_animation_scale =
 419         parent_node->data.combined_starting_animation_scale;
 420   }
 421   node->data.to_screen_is_animated =
 422       node->data.is_animated || ancestor_is_animating;
 423   node->data.to_screen_has_scale_animation =
 424       !node->data.has_only_translation_animations ||
 425       ancestor_is_animating_scale;
 426
 427   // Once we've failed to compute a maximum animated scale at an ancestor, we
 428   // continue to fail.
 429   bool failed_at_ancestor =
 430       ancestor_is_animating_scale && ancestor_maximum_target_scale == 0.f;
 431
 432   // Computing maximum animated scale in the presence of non-scale/translation
 433   // transforms isn't supported.
 434   bool failed_for_non_scale_or_translation =
 435       !node->data.to_target.IsScaleOrTranslation();
 436
 437   // We don't attempt to accumulate animation scale from multiple nodes with
 438   // scale animations, because of the risk of significant overestimation. For
 439   // example, one node might be increasing scale from 1 to 10 at the same time
 440   // as another node is decreasing scale from 10 to 1. Naively combining these
 441   // scales would produce a scale of 100.
 442   bool failed_for_multiple_scale_animations =
 443       ancestor_is_animating_scale &&
 444       !node->data.has_only_translation_animations;
 445
 446   if (failed_at_ancestor || failed_for_non_scale_or_translation ||
 447       failed_for_multiple_scale_animations) {
 448     node->data.combined_maximum_animation_target_scale = 0.f;
 449     node->data.combined_starting_animation_scale = 0.f;
 450
 451     // This ensures that descendants know we've failed to compute a maximum
 452     // animated scale.
 453     node->data.to_screen_has_scale_animation = true;
 454     return;
 455   }
 456
 457   if (!node->data.to_screen_has_scale_animation) {
 458     node->data.combined_maximum_animation_target_scale = 0.f;
 459     node->data.combined_starting_animation_scale = 0.f;
 460     return;
 461   }
 462
 463   // At this point, we know exactly one of this node or an ancestor is animating
 464   // scale.
 465   if (node->data.has_only_translation_animations) {
 466     // An ancestor is animating scale.
 467     gfx::Vector2dF local_scales =
 468         MathUtil::ComputeTransform2dScaleComponents(node->data.local, 0.f);
 469     float max_local_scale = std::max(local_scales.x(), local_scales.y());
 470     node->data.combined_maximum_animation_target_scale =
 471         max_local_scale * ancestor_maximum_target_scale;
 472     node->data.combined_starting_animation_scale =
 473         max_local_scale * ancestor_starting_animation_scale;
 474     return;
 475   }
 476
 477   if (node->data.local_starting_animation_scale == 0.f ||
 478       node->data.local_maximum_animation_target_scale == 0.f) {
 479     node->data.combined_maximum_animation_target_scale = 0.f;
 480     node->data.combined_starting_animation_scale = 0.f;
 481     return;
 482   }
 483
 484   gfx::Vector2dF ancestor_scales =
 485       parent_node ? MathUtil::ComputeTransform2dScaleComponents(
 486                         parent_node->data.to_target, 0.f)
 487                   : gfx::Vector2dF(1.f, 1.f);
 488   float max_ancestor_scale = std::max(ancestor_scales.x(), ancestor_scales.y());
 489   node->data.combined_maximum_animation_target_scale =
 490       max_ancestor_scale * node->data.local_maximum_animation_target_scale;
 491   node->data.combined_starting_animation_scale =
 492       max_ancestor_scale * node->data.local_starting_animation_scale;
 493 }
 494
 495 void TransformTree::UpdateSnapping(TransformNode* node) {
 496   if (!node->data.scrolls || node->data.to_screen_is_animated ||
 497       !node->data.to_target.IsScaleOrTranslation()) {
 498     return;
 499   }
 500
 501   // Scroll snapping must be done in target space (the pixels we care about).
 502   // This means we effectively snap the target space transform. If TT is the
 503   // target space transform and TT' is TT with its translation components
 504   // rounded, then what we're after is the scroll delta X, where TT * X = TT'.
 505   // I.e., we want a transform that will realize our scroll snap. It follows
 506   // that X = TT^-1 * TT'. We cache TT and TT^-1 to make this more efficient.
 507   gfx::Transform rounded = node->data.to_target;
 508   rounded.RoundTranslationComponents();
 509   gfx::Transform delta = node->data.from_target;
 510   delta *= rounded;
 511
 512   DCHECK(delta.IsApproximatelyIdentityOrTranslation(SkDoubleToMScalar(1e-4)))
 513       << delta.ToString();
 514
 515   gfx::Vector2dF translation = delta.To2dTranslation();
 516
 517   // Now that we have our scroll delta, we must apply it to each of our
 518   // combined, to/from matrices.
 519   node->data.to_parent.Translate(translation.x(), translation.y());
 520   node->data.to_target.Translate(translation.x(), translation.y());
 521   node->data.from_target.matrix().postTranslate(-translation.x(),
 522                                                 -translation.y(), 0);
 523   node->data.to_screen.Translate(translation.x(), translation.y());
 524   node->data.from_screen.matrix().postTranslate(-translation.x(),
 525                                                 -translation.y(), 0);
 526
 527   node->data.scroll_snap = translation;
 528 }
 529
 530 void TransformTree::SetInnerViewportBoundsDelta(gfx::Vector2dF bounds_delta) {
 531   if (inner_viewport_bounds_delta_ == bounds_delta)
 532     return;
 533
 534   inner_viewport_bounds_delta_ = bounds_delta;
 535
 536   if (nodes_affected_by_inner_viewport_bounds_delta_.empty())
 537     return;
 538
 539   set_needs_update(true);
 540   for (int i : nodes_affected_by_inner_viewport_bounds_delta_)
 541     Node(i)->data.needs_local_transform_update = true;
 542 }
 543
 544 void TransformTree::SetOuterViewportBoundsDelta(gfx::Vector2dF bounds_delta) {
 545   if (outer_viewport_bounds_delta_ == bounds_delta)
 546     return;
 547
 548   outer_viewport_bounds_delta_ = bounds_delta;
 549
 550   if (nodes_affected_by_outer_viewport_bounds_delta_.empty())
 551     return;
 552
 553   set_needs_update(true);
 554   for (int i : nodes_affected_by_outer_viewport_bounds_delta_)
 555     Node(i)->data.needs_local_transform_update = true;
 556 }
 557
 558 void TransformTree::AddNodeAffectedByInnerViewportBoundsDelta(int node_id) {
 559   nodes_affected_by_inner_viewport_bounds_delta_.push_back(node_id);
 560 }
 561
 562 void TransformTree::AddNodeAffectedByOuterViewportBoundsDelta(int node_id) {
 563   nodes_affected_by_outer_viewport_bounds_delta_.push_back(node_id);
 564 }
 565
 566 bool TransformTree::HasNodesAffectedByInnerViewportBoundsDelta() const {
 567   return !nodes_affected_by_inner_viewport_bounds_delta_.empty();
 568 }
 569
 570 bool TransformTree::HasNodesAffectedByOuterViewportBoundsDelta() const {
 571   return !nodes_affected_by_outer_viewport_bounds_delta_.empty();
 572 }
 573
 574 void EffectTree::UpdateOpacities(int id) {
 575   EffectNode* node = Node(id);
 576   node->data.screen_space_opacity = node->data.opacity;
 577
 578   EffectNode* parent_node = parent(node);
 579   if (parent_node)
 580     node->data.screen_space_opacity *= parent_node->data.screen_space_opacity;
 581 }
 582
 583 void TransformTree::UpdateNodeAndAncestorsHaveIntegerTranslations(
 584     TransformNode* node,
 585     TransformNode* parent_node) {
 586   node->data.node_and_ancestors_have_only_integer_translation =
 587       node->data.to_parent.IsIdentityOrIntegerTranslation();
 588   if (parent_node)
 589     node->data.node_and_ancestors_have_only_integer_translation =
 590         node->data.node_and_ancestors_have_only_integer_translation &&
 591         parent_node->data.node_and_ancestors_have_only_integer_translation;
 592 }
 593
 594 PropertyTrees::PropertyTrees() : needs_rebuild(true), sequence_number(0) {
 595 }
 596
 597 }  // namespace cc