cc/trees/layer_tree_impl.cc

   1 // Copyright 2011 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 "cc/trees/layer_tree_impl.h"
   6
   7 #include <algorithm>
   8 #include <limits>
   9 #include <set>
  10
  11 #include "base/trace_event/trace_event.h"
  12 #include "base/trace_event/trace_event_argument.h"
  13 #include "cc/animation/animation_host.h"
  14 #include "cc/animation/keyframed_animation_curve.h"
  15 #include "cc/animation/scrollbar_animation_controller.h"
  16 #include "cc/animation/scrollbar_animation_controller_linear_fade.h"
  17 #include "cc/animation/scrollbar_animation_controller_thinning.h"
  18 #include "cc/base/math_util.h"
  19 #include "cc/base/synced_property.h"
  20 #include "cc/debug/devtools_instrumentation.h"
  21 #include "cc/debug/traced_value.h"
  22 #include "cc/input/layer_scroll_offset_delegate.h"
  23 #include "cc/input/page_scale_animation.h"
  24 #include "cc/layers/heads_up_display_layer_impl.h"
  25 #include "cc/layers/layer.h"
  26 #include "cc/layers/layer_iterator.h"
  27 #include "cc/layers/render_surface_impl.h"
  28 #include "cc/layers/scrollbar_layer_impl_base.h"
  29 #include "cc/resources/ui_resource_request.h"
  30 #include "cc/trees/layer_tree_host_common.h"
  31 #include "cc/trees/layer_tree_host_impl.h"
  32 #include "cc/trees/occlusion_tracker.h"
  33 #include "cc/trees/property_tree.h"
  34 #include "cc/trees/property_tree_builder.h"
  35 #include "ui/gfx/geometry/box_f.h"
  36 #include "ui/gfx/geometry/point_conversions.h"
  37 #include "ui/gfx/geometry/size_conversions.h"
  38 #include "ui/gfx/geometry/vector2d_conversions.h"
  39
  40 namespace cc {
  41
  42 LayerTreeImpl::LayerTreeImpl(
  43     LayerTreeHostImpl* layer_tree_host_impl,
  44     scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor,
  45     scoped_refptr<SyncedTopControls> top_controls_shown_ratio,
  46     scoped_refptr<SyncedElasticOverscroll> elastic_overscroll)
  47     : layer_tree_host_impl_(layer_tree_host_impl),
  48       source_frame_number_(-1),
  49       hud_layer_(0),
  50       root_layer_scroll_offset_delegate_(NULL),
  51       background_color_(0),
  52       has_transparent_background_(false),
  53       currently_scrolling_layer_id_(Layer::INVALID_ID),
  54       overscroll_elasticity_layer_id_(Layer::INVALID_ID),
  55       page_scale_layer_id_(Layer::INVALID_ID),
  56       inner_viewport_scroll_layer_id_(Layer::INVALID_ID),
  57       outer_viewport_scroll_layer_id_(Layer::INVALID_ID),
  58       page_scale_factor_(page_scale_factor),
  59       min_page_scale_factor_(0),
  60       max_page_scale_factor_(0),
  61       hide_pinch_scrollbars_near_min_scale_(false),
  62       elastic_overscroll_(elastic_overscroll),
  63       viewport_size_invalid_(false),
  64       needs_update_draw_properties_(true),
  65       needs_full_tree_sync_(true),
  66       next_activation_forces_redraw_(false),
  67       has_ever_been_drawn_(false),
  68       render_surface_layer_list_id_(0),
  69       top_controls_shrink_blink_size_(false),
  70       top_controls_height_(0),
  71       top_controls_shown_ratio_(top_controls_shown_ratio) {
  72 }
  73
  74 LayerTreeImpl::~LayerTreeImpl() {
  75   BreakSwapPromises(IsActiveTree() ? SwapPromise::SWAP_FAILS
  76                                    : SwapPromise::ACTIVATION_FAILS);
  77
  78   // Need to explicitly clear the tree prior to destroying this so that
  79   // the LayerTreeImpl pointer is still valid in the LayerImpl dtor.
  80   DCHECK(!root_layer_);
  81   DCHECK(layers_with_copy_output_request_.empty());
  82 }
  83
  84 void LayerTreeImpl::Shutdown() {
  85   root_layer_ = nullptr;
  86 }
  87
  88 void LayerTreeImpl::ReleaseResources() {
  89   if (root_layer_) {
  90     LayerTreeHostCommon::CallFunctionForSubtree(
  91         root_layer_.get(), [](LayerImpl* layer) { layer->ReleaseResources(); });
  92   }
  93 }
  94
  95 void LayerTreeImpl::RecreateResources() {
  96   if (root_layer_) {
  97     LayerTreeHostCommon::CallFunctionForSubtree(
  98         root_layer_.get(),
  99         [](LayerImpl* layer) { layer->RecreateResources(); });
 100   }
 101 }
 102
 103 void LayerTreeImpl::GatherFrameTimingRequestIds(
 104     std::vector<int64_t>* request_ids) {
 105   if (!root_layer_)
 106     return;
 107
 108   // TODO(vmpstr): Early out if there are no requests on any of the layers. For
 109   // that, we need to inform LayerTreeImpl whenever there are requests when we
 110   // get them.
 111   LayerTreeHostCommon::CallFunctionForSubtree(
 112       root_layer_.get(), [request_ids](LayerImpl* layer) {
 113         layer->GatherFrameTimingRequestIds(request_ids);
 114       });
 115 }
 116
 117 bool LayerTreeImpl::IsExternalScrollActive() const {
 118   return root_layer_scroll_offset_delegate_ &&
 119          root_layer_scroll_offset_delegate_->IsExternalScrollActive();
 120 }
 121
 122 void LayerTreeImpl::DidUpdateScrollOffset(int layer_id) {
 123   int inner_layer_id = InnerViewportScrollLayer()
 124                            ? InnerViewportScrollLayer()->id()
 125                            : Layer::INVALID_ID;
 126   int outer_layer_id = OuterViewportScrollLayer()
 127                            ? OuterViewportScrollLayer()->id()
 128                            : Layer::INVALID_ID;
 129   if (layer_id != outer_layer_id && layer_id != inner_layer_id)
 130     return;
 131
 132   if (!root_layer_scroll_offset_delegate_)
 133     return;
 134
 135   UpdateRootScrollOffsetDelegate();
 136 }
 137
 138 void LayerTreeImpl::SetRootLayer(scoped_ptr<LayerImpl> layer) {
 139   root_layer_ = layer.Pass();
 140
 141   layer_tree_host_impl_->OnCanDrawStateChangedForTree();
 142 }
 143
 144 LayerImpl* LayerTreeImpl::InnerViewportScrollLayer() const {
 145   return LayerById(inner_viewport_scroll_layer_id_);
 146 }
 147
 148 LayerImpl* LayerTreeImpl::OuterViewportScrollLayer() const {
 149   return LayerById(outer_viewport_scroll_layer_id_);
 150 }
 151
 152 gfx::ScrollOffset LayerTreeImpl::TotalScrollOffset() const {
 153   gfx::ScrollOffset offset;
 154
 155   if (InnerViewportScrollLayer())
 156     offset += InnerViewportScrollLayer()->CurrentScrollOffset();
 157
 158   if (OuterViewportScrollLayer())
 159     offset += OuterViewportScrollLayer()->CurrentScrollOffset();
 160
 161   return offset;
 162 }
 163
 164 gfx::ScrollOffset LayerTreeImpl::TotalMaxScrollOffset() const {
 165   gfx::ScrollOffset offset;
 166
 167   if (InnerViewportScrollLayer())
 168     offset += InnerViewportScrollLayer()->MaxScrollOffset();
 169
 170   if (OuterViewportScrollLayer())
 171     offset += OuterViewportScrollLayer()->MaxScrollOffset();
 172
 173   return offset;
 174 }
 175
 176 scoped_ptr<LayerImpl> LayerTreeImpl::DetachLayerTree() {
 177   render_surface_layer_list_.clear();
 178   set_needs_update_draw_properties();
 179   return root_layer_.Pass();
 180 }
 181
 182 static void UpdateClipTreeForBoundsDeltaOnLayer(LayerImpl* layer,
 183                                                 ClipTree* clip_tree) {
 184   if (layer && layer->masks_to_bounds()) {
 185     ClipNode* clip_node = clip_tree->Node(layer->clip_tree_index());
 186     if (clip_node) {
 187       DCHECK_EQ(layer->id(), clip_node->owner_id);
 188       gfx::Size bounds = layer->bounds();
 189       if (clip_node->data.clip.size() != bounds) {
 190         clip_node->data.clip.set_size(bounds);
 191         clip_tree->set_needs_update(true);
 192       }
 193     }
 194   }
 195 }
 196
 197 void LayerTreeImpl::UpdatePropertyTreesForBoundsDelta() {
 198   DCHECK(IsActiveTree());
 199   LayerImpl* inner_container = InnerViewportContainerLayer();
 200   LayerImpl* outer_container = OuterViewportContainerLayer();
 201
 202   UpdateClipTreeForBoundsDeltaOnLayer(inner_container,
 203                                       &property_trees_.clip_tree);
 204   UpdateClipTreeForBoundsDeltaOnLayer(InnerViewportScrollLayer(),
 205                                       &property_trees_.clip_tree);
 206   UpdateClipTreeForBoundsDeltaOnLayer(outer_container,
 207                                       &property_trees_.clip_tree);
 208
 209   TransformTree& transform_tree = property_trees_.transform_tree;
 210   if (inner_container)
 211     transform_tree.SetInnerViewportBoundsDelta(inner_container->bounds_delta());
 212   if (outer_container)
 213     transform_tree.SetOuterViewportBoundsDelta(outer_container->bounds_delta());
 214 }
 215
 216 void LayerTreeImpl::PushPropertiesTo(LayerTreeImpl* target_tree) {
 217   // The request queue should have been processed and does not require a push.
 218   DCHECK_EQ(ui_resource_request_queue_.size(), 0u);
 219
 220   target_tree->SetPropertyTrees(property_trees_);
 221
 222   if (next_activation_forces_redraw_) {
 223     target_tree->ForceRedrawNextActivation();
 224     next_activation_forces_redraw_ = false;
 225   }
 226
 227   target_tree->PassSwapPromises(&swap_promise_list_);
 228
 229   target_tree->set_top_controls_shrink_blink_size(
 230       top_controls_shrink_blink_size_);
 231   target_tree->set_top_controls_height(top_controls_height_);
 232   target_tree->PushTopControls(nullptr);
 233
 234   target_tree->set_hide_pinch_scrollbars_near_min_scale(
 235       hide_pinch_scrollbars_near_min_scale_);
 236
 237   // Active tree already shares the page_scale_factor object with pending
 238   // tree so only the limits need to be provided.
 239   target_tree->PushPageScaleFactorAndLimits(nullptr, min_page_scale_factor(),
 240                                             max_page_scale_factor());
 241   target_tree->elastic_overscroll()->PushPendingToActive();
 242
 243   target_tree->pending_page_scale_animation_ =
 244       pending_page_scale_animation_.Pass();
 245
 246   target_tree->SetViewportLayersFromIds(
 247       overscroll_elasticity_layer_id_, page_scale_layer_id_,
 248       inner_viewport_scroll_layer_id_, outer_viewport_scroll_layer_id_);
 249
 250   target_tree->RegisterSelection(selection_);
 251
 252   // This should match the property synchronization in
 253   // LayerTreeHost::finishCommitOnImplThread().
 254   target_tree->set_source_frame_number(source_frame_number());
 255   target_tree->set_background_color(background_color());
 256   target_tree->set_has_transparent_background(has_transparent_background());
 257
 258   if (ViewportSizeInvalid())
 259     target_tree->SetViewportSizeInvalid();
 260   else
 261     target_tree->ResetViewportSizeInvalid();
 262
 263   if (hud_layer())
 264     target_tree->set_hud_layer(static_cast<HeadsUpDisplayLayerImpl*>(
 265         LayerTreeHostCommon::FindLayerInSubtree(
 266             target_tree->root_layer(), hud_layer()->id())));
 267   else
 268     target_tree->set_hud_layer(NULL);
 269
 270   target_tree->has_ever_been_drawn_ = false;
 271 }
 272
 273 LayerImpl* LayerTreeImpl::InnerViewportContainerLayer() const {
 274   return InnerViewportScrollLayer()
 275              ? InnerViewportScrollLayer()->scroll_clip_layer()
 276              : NULL;
 277 }
 278
 279 LayerImpl* LayerTreeImpl::OuterViewportContainerLayer() const {
 280   return OuterViewportScrollLayer()
 281              ? OuterViewportScrollLayer()->scroll_clip_layer()
 282              : NULL;
 283 }
 284
 285 LayerImpl* LayerTreeImpl::CurrentlyScrollingLayer() const {
 286   DCHECK(IsActiveTree());
 287   return LayerById(currently_scrolling_layer_id_);
 288 }
 289
 290 void LayerTreeImpl::SetCurrentlyScrollingLayer(LayerImpl* layer) {
 291   int new_id = layer ? layer->id() : Layer::INVALID_ID;
 292   if (currently_scrolling_layer_id_ == new_id)
 293     return;
 294
 295   if (CurrentlyScrollingLayer() &&
 296       CurrentlyScrollingLayer()->scrollbar_animation_controller())
 297     CurrentlyScrollingLayer()->scrollbar_animation_controller()->DidScrollEnd();
 298   currently_scrolling_layer_id_ = new_id;
 299   if (layer && layer->scrollbar_animation_controller())
 300     layer->scrollbar_animation_controller()->DidScrollBegin();
 301 }
 302
 303 void LayerTreeImpl::ClearCurrentlyScrollingLayer() {
 304   SetCurrentlyScrollingLayer(NULL);
 305 }
 306
 307 namespace {
 308
 309 void ForceScrollbarParameterUpdateAfterScaleChange(LayerImpl* current_layer) {
 310   if (!current_layer)
 311     return;
 312
 313   while (current_layer) {
 314     current_layer->ScrollbarParametersDidChange(false);
 315     current_layer = current_layer->parent();
 316   }
 317 }
 318
 319 }  // namespace
 320
 321 float LayerTreeImpl::ClampPageScaleFactorToLimits(
 322     float page_scale_factor) const {
 323   if (min_page_scale_factor_ && page_scale_factor < min_page_scale_factor_)
 324     page_scale_factor = min_page_scale_factor_;
 325   else if (max_page_scale_factor_ && page_scale_factor > max_page_scale_factor_)
 326     page_scale_factor = max_page_scale_factor_;
 327   return page_scale_factor;
 328 }
 329
 330 void LayerTreeImpl::UpdatePropertyTreeScrollingAndAnimationFromMainThread() {
 331   // TODO(enne): This should get replaced by pulling out scrolling and
 332   // animations into their own trees.  Then scrolls and animations would have
 333   // their own ways of synchronizing across commits.  This occurs to push
 334   // updates from scrolling deltas on the compositor thread that have occurred
 335   // after begin frame and updates from animations that have ticked since begin
 336   // frame to a newly-committed property tree.
 337   if (!root_layer())
 338     return;
 339   LayerTreeHostCommon::CallFunctionForSubtree(
 340       root_layer(), [](LayerImpl* layer) {
 341         layer->UpdatePropertyTreeForScrollingAndAnimationIfNeeded();
 342       });
 343 }
 344
 345 void LayerTreeImpl::SetPageScaleOnActiveTree(float active_page_scale) {
 346   DCHECK(IsActiveTree());
 347   if (page_scale_factor()->SetCurrent(
 348           ClampPageScaleFactorToLimits(active_page_scale)))
 349     DidUpdatePageScale();
 350 }
 351
 352 void LayerTreeImpl::PushPageScaleFromMainThread(float page_scale_factor,
 353                                                 float min_page_scale_factor,
 354                                                 float max_page_scale_factor) {
 355   PushPageScaleFactorAndLimits(&page_scale_factor, min_page_scale_factor,
 356                                max_page_scale_factor);
 357 }
 358
 359 void LayerTreeImpl::PushPageScaleFactorAndLimits(const float* page_scale_factor,
 360                                                  float min_page_scale_factor,
 361                                                  float max_page_scale_factor) {
 362   DCHECK(page_scale_factor || IsActiveTree());
 363   bool changed_page_scale = false;
 364   if (page_scale_factor) {
 365     DCHECK(!IsActiveTree() || !layer_tree_host_impl_->pending_tree());
 366     changed_page_scale |= page_scale_factor_->Delta() != 1.f;
 367     // TODO(enne): Once CDP goes away, ignore this call below.  The only time
 368     // the property trees will differ is if there's been a page scale on the
 369     // compositor thread after the begin frame, which is the delta check above.
 370     changed_page_scale |=
 371         page_scale_factor_->PushFromMainThread(*page_scale_factor);
 372   }
 373   if (IsActiveTree()) {
 374     // TODO(enne): Pushing from pending to active should never require
 375     // DidUpdatePageScale.  The values should already be set by the fully
 376     // computed property trees being synced from one tree to another.  Remove
 377     // this once CDP goes away.
 378     changed_page_scale |= page_scale_factor_->PushPendingToActive();
 379   }
 380
 381   changed_page_scale |=
 382       SetPageScaleFactorLimits(min_page_scale_factor, max_page_scale_factor);
 383
 384   if (changed_page_scale)
 385     DidUpdatePageScale();
 386 }
 387
 388 void LayerTreeImpl::set_top_controls_shrink_blink_size(bool shrink) {
 389   if (top_controls_shrink_blink_size_ == shrink)
 390     return;
 391
 392   top_controls_shrink_blink_size_ = shrink;
 393   if (IsActiveTree())
 394     layer_tree_host_impl_->UpdateViewportContainerSizes();
 395 }
 396
 397 void LayerTreeImpl::set_top_controls_height(float top_controls_height) {
 398   if (top_controls_height_ == top_controls_height)
 399     return;
 400
 401   top_controls_height_ = top_controls_height;
 402   if (IsActiveTree())
 403     layer_tree_host_impl_->UpdateViewportContainerSizes();
 404 }
 405
 406 bool LayerTreeImpl::SetCurrentTopControlsShownRatio(float ratio) {
 407   ratio = std::max(ratio, 0.f);
 408   ratio = std::min(ratio, 1.f);
 409   return top_controls_shown_ratio_->SetCurrent(ratio);
 410 }
 411
 412 void LayerTreeImpl::PushTopControlsFromMainThread(
 413     float top_controls_shown_ratio) {
 414   PushTopControls(&top_controls_shown_ratio);
 415 }
 416
 417 void LayerTreeImpl::PushTopControls(const float* top_controls_shown_ratio) {
 418   DCHECK(top_controls_shown_ratio || IsActiveTree());
 419
 420   if (top_controls_shown_ratio) {
 421     DCHECK(!IsActiveTree() || !layer_tree_host_impl_->pending_tree());
 422     top_controls_shown_ratio_->PushFromMainThread(*top_controls_shown_ratio);
 423   }
 424   if (IsActiveTree()) {
 425     if (top_controls_shown_ratio_->PushPendingToActive())
 426       layer_tree_host_impl_->DidChangeTopControlsPosition();
 427   }
 428 }
 429
 430 bool LayerTreeImpl::SetPageScaleFactorLimits(float min_page_scale_factor,
 431                                              float max_page_scale_factor) {
 432   if (min_page_scale_factor == min_page_scale_factor_ &&
 433       max_page_scale_factor == max_page_scale_factor_)
 434     return false;
 435
 436   min_page_scale_factor_ = min_page_scale_factor;
 437   max_page_scale_factor_ = max_page_scale_factor;
 438
 439   return true;
 440 }
 441
 442 void LayerTreeImpl::DidUpdatePageScale() {
 443   if (IsActiveTree())
 444     page_scale_factor()->SetCurrent(
 445         ClampPageScaleFactorToLimits(current_page_scale_factor()));
 446
 447   set_needs_update_draw_properties();
 448
 449   if (root_layer_scroll_offset_delegate_) {
 450     root_layer_scroll_offset_delegate_->UpdateRootLayerState(
 451         TotalScrollOffset(), TotalMaxScrollOffset(), ScrollableSize(),
 452         current_page_scale_factor(), min_page_scale_factor_,
 453         max_page_scale_factor_);
 454   }
 455
 456   if (PageScaleLayer() && PageScaleLayer()->transform_tree_index() != -1) {
 457     TransformNode* node = property_trees_.transform_tree.Node(
 458         PageScaleLayer()->transform_tree_index());
 459     node->data.post_local_scale_factor = current_page_scale_factor();
 460     node->data.needs_local_transform_update = true;
 461     // TODO(enne): property trees can't ask the layer these things, but
 462     // the page scale layer should *just* be the page scale.
 463     DCHECK_EQ(PageScaleLayer()->position().ToString(),
 464               gfx::PointF().ToString());
 465     DCHECK_EQ(PageScaleLayer()->transform_origin().ToString(),
 466               gfx::Point3F().ToString());
 467     node->data.update_post_local_transform(gfx::PointF(), gfx::Point3F());
 468     property_trees_.transform_tree.set_needs_update(true);
 469   }
 470
 471   ForceScrollbarParameterUpdateAfterScaleChange(PageScaleLayer());
 472   HideInnerViewportScrollbarsIfNeeded();
 473 }
 474
 475 void LayerTreeImpl::HideInnerViewportScrollbarsIfNeeded() {
 476   if (!InnerViewportContainerLayer())
 477     return;
 478
 479   LayerImpl::ScrollbarSet* scrollbars =
 480       InnerViewportContainerLayer()->scrollbars();
 481
 482   if (!scrollbars)
 483     return;
 484
 485   float minimum_scale_to_show_at = min_page_scale_factor() * 1.05f;
 486   bool hide_scrollbars =
 487       hide_pinch_scrollbars_near_min_scale_ &&
 488       (current_page_scale_factor() < minimum_scale_to_show_at);
 489
 490   for (LayerImpl::ScrollbarSet::iterator it = scrollbars->begin();
 491        it != scrollbars->end(); ++it)
 492     (*it)->SetHideLayerAndSubtree(hide_scrollbars);
 493 }
 494
 495 SyncedProperty<ScaleGroup>* LayerTreeImpl::page_scale_factor() {
 496   return page_scale_factor_.get();
 497 }
 498
 499 const SyncedProperty<ScaleGroup>* LayerTreeImpl::page_scale_factor() const {
 500   return page_scale_factor_.get();
 501 }
 502
 503 gfx::SizeF LayerTreeImpl::ScrollableViewportSize() const {
 504   if (!InnerViewportContainerLayer())
 505     return gfx::SizeF();
 506
 507   return gfx::ScaleSize(InnerViewportContainerLayer()->BoundsForScrolling(),
 508                         1.0f / current_page_scale_factor());
 509 }
 510
 511 gfx::Rect LayerTreeImpl::RootScrollLayerDeviceViewportBounds() const {
 512   LayerImpl* root_scroll_layer = OuterViewportScrollLayer()
 513                                      ? OuterViewportScrollLayer()
 514                                      : InnerViewportScrollLayer();
 515   if (!root_scroll_layer || root_scroll_layer->children().empty())
 516     return gfx::Rect();
 517   LayerImpl* layer = root_scroll_layer->children()[0];
 518   return MathUtil::MapEnclosingClippedRect(layer->screen_space_transform(),
 519                                            gfx::Rect(layer->bounds()));
 520 }
 521
 522 void LayerTreeImpl::ApplySentScrollAndScaleDeltasFromAbortedCommit() {
 523   DCHECK(IsActiveTree());
 524
 525   page_scale_factor()->AbortCommit();
 526   top_controls_shown_ratio()->AbortCommit();
 527   elastic_overscroll()->AbortCommit();
 528
 529   if (!root_layer())
 530     return;
 531
 532   LayerTreeHostCommon::CallFunctionForSubtree(
 533       root_layer(), [](LayerImpl* layer) {
 534         layer->ApplySentScrollDeltasFromAbortedCommit();
 535       });
 536 }
 537
 538 void LayerTreeImpl::SetViewportLayersFromIds(
 539     int overscroll_elasticity_layer_id,
 540     int page_scale_layer_id,
 541     int inner_viewport_scroll_layer_id,
 542     int outer_viewport_scroll_layer_id) {
 543   overscroll_elasticity_layer_id_ = overscroll_elasticity_layer_id;
 544   page_scale_layer_id_ = page_scale_layer_id;
 545   inner_viewport_scroll_layer_id_ = inner_viewport_scroll_layer_id;
 546   outer_viewport_scroll_layer_id_ = outer_viewport_scroll_layer_id;
 547
 548   HideInnerViewportScrollbarsIfNeeded();
 549 }
 550
 551 void LayerTreeImpl::ClearViewportLayers() {
 552   overscroll_elasticity_layer_id_ = Layer::INVALID_ID;
 553   page_scale_layer_id_ = Layer::INVALID_ID;
 554   inner_viewport_scroll_layer_id_ = Layer::INVALID_ID;
 555   outer_viewport_scroll_layer_id_ = Layer::INVALID_ID;
 556 }
 557
 558 bool LayerTreeImpl::UpdateDrawProperties(bool update_lcd_text) {
 559   if (!needs_update_draw_properties_)
 560     return true;
 561
 562   // Calling UpdateDrawProperties must clear this flag, so there can be no
 563   // early outs before this.
 564   needs_update_draw_properties_ = false;
 565
 566   // For max_texture_size.  When the renderer is re-created in
 567   // CreateAndSetRenderer, the needs update draw properties flag is set
 568   // again.
 569   if (!layer_tree_host_impl_->renderer())
 570     return false;
 571
 572   // Clear this after the renderer early out, as it should still be
 573   // possible to hit test even without a renderer.
 574   render_surface_layer_list_.clear();
 575
 576   if (!root_layer())
 577     return false;
 578
 579   {
 580     TRACE_EVENT2(
 581         "cc", "LayerTreeImpl::UpdateDrawProperties::CalculateDrawProperties",
 582         "IsActive", IsActiveTree(), "SourceFrameNumber", source_frame_number_);
 583     bool can_render_to_separate_surface =
 584         (layer_tree_host_impl_->GetDrawMode() !=
 585          DRAW_MODE_RESOURCELESS_SOFTWARE);
 586
 587     ++render_surface_layer_list_id_;
 588
 589     LayerTreeHostCommon::CalcDrawPropsImplInputs inputs(
 590         root_layer(), DrawViewportSize(),
 591         layer_tree_host_impl_->DrawTransform(), device_scale_factor(),
 592         current_page_scale_factor(), PageScaleLayer(),
 593         InnerViewportScrollLayer(), OuterViewportScrollLayer(),
 594         elastic_overscroll()->Current(IsActiveTree()),
 595         OverscrollElasticityLayer(), resource_provider()->max_texture_size(),
 596         settings().can_use_lcd_text, settings().layers_always_allowed_lcd_text,
 597         can_render_to_separate_surface,
 598         settings().layer_transforms_should_scale_layer_contents,
 599         settings().verify_property_trees, &render_surface_layer_list_,
 600         render_surface_layer_list_id_, &property_trees_);
 601     LayerTreeHostCommon::CalculateDrawProperties(&inputs);
 602   }
 603
 604   {
 605     TRACE_EVENT2("cc", "LayerTreeImpl::UpdateDrawProperties::Occlusion",
 606                  "IsActive", IsActiveTree(), "SourceFrameNumber",
 607                  source_frame_number_);
 608     OcclusionTracker occlusion_tracker(
 609         root_layer()->render_surface()->content_rect());
 610     occlusion_tracker.set_minimum_tracking_size(
 611         settings().minimum_occlusion_tracking_size);
 612
 613     // LayerIterator is used here instead of CallFunctionForSubtree to only
 614     // UpdateTilePriorities on layers that will be visible (and thus have valid
 615     // draw properties) and not because any ordering is required.
 616     LayerIterator end = LayerIterator::End(&render_surface_layer_list_);
 617     for (LayerIterator it = LayerIterator::Begin(&render_surface_layer_list_);
 618          it != end; ++it) {
 619       occlusion_tracker.EnterLayer(it);
 620
 621       // There are very few render targets so this should be cheap to do for
 622       // each layer instead of something more complicated.
 623       bool inside_replica = false;
 624       LayerImpl* layer = it->render_target();
 625       while (layer && !inside_replica) {
 626         if (layer->render_target()->has_replica())
 627           inside_replica = true;
 628         layer = layer->render_target()->parent();
 629       }
 630
 631       // Don't use occlusion if a layer will appear in a replica, since the
 632       // tile raster code does not know how to look for the replica and would
 633       // consider it occluded even though the replica is visible.
 634       // Since occlusion is only used for browser compositor (i.e.
 635       // use_occlusion_for_tile_prioritization) and it won't use replicas,
 636       // this should matter not.
 637
 638       if (it.represents_itself()) {
 639         Occlusion occlusion =
 640             inside_replica ? Occlusion()
 641                            : occlusion_tracker.GetCurrentOcclusionForLayer(
 642                                  it->draw_transform());
 643         it->draw_properties().occlusion_in_content_space = occlusion;
 644       }
 645
 646       if (it.represents_contributing_render_surface()) {
 647         // Surfaces aren't used by the tile raster code, so they can have
 648         // occlusion regardless of replicas.
 649         Occlusion occlusion =
 650             occlusion_tracker.GetCurrentOcclusionForContributingSurface(
 651                 it->render_surface()->draw_transform());
 652         it->render_surface()->set_occlusion_in_content_space(occlusion);
 653         // Masks are used to draw the contributing surface, so should have
 654         // the same occlusion as the surface (nothing inside the surface
 655         // occludes them).
 656         if (LayerImpl* mask = it->mask_layer()) {
 657           Occlusion mask_occlusion =
 658               inside_replica
 659                   ? Occlusion()
 660                   : occlusion_tracker.GetCurrentOcclusionForContributingSurface(
 661                         it->render_surface()->draw_transform() *
 662                         it->draw_transform());
 663           mask->draw_properties().occlusion_in_content_space = mask_occlusion;
 664         }
 665         if (LayerImpl* replica = it->replica_layer()) {
 666           if (LayerImpl* mask = replica->mask_layer())
 667             mask->draw_properties().occlusion_in_content_space = Occlusion();
 668         }
 669       }
 670
 671       occlusion_tracker.LeaveLayer(it);
 672     }
 673
 674     unoccluded_screen_space_region_ =
 675         occlusion_tracker.ComputeVisibleRegionInScreen();
 676   }
 677
 678   // It'd be ideal if this could be done earlier, but when the raster source
 679   // is updated from the main thread during push properties, update draw
 680   // properties has not occurred yet and so it's not clear whether or not the
 681   // layer can or cannot use lcd text.  So, this is the cleanup pass to
 682   // determine if the raster source needs to be replaced with a non-lcd
 683   // raster source due to draw properties.
 684   if (update_lcd_text) {
 685     // TODO(enne): Make LTHI::sync_tree return this value.
 686     LayerTreeImpl* sync_tree =
 687         layer_tree_host_impl_->proxy()->CommitToActiveTree()
 688             ? layer_tree_host_impl_->active_tree()
 689             : layer_tree_host_impl_->pending_tree();
 690     // If this is not the sync tree, then it is not safe to update lcd text
 691     // as it causes invalidations and the tiles may be in use.
 692     DCHECK_EQ(this, sync_tree);
 693     for (const auto& layer : picture_layers_)
 694       layer->UpdateCanUseLCDTextAfterCommit();
 695   }
 696
 697   {
 698     TRACE_EVENT_BEGIN2("cc", "LayerTreeImpl::UpdateDrawProperties::UpdateTiles",
 699                        "IsActive", IsActiveTree(), "SourceFrameNumber",
 700                        source_frame_number_);
 701     const bool resourceless_software_draw =
 702         (layer_tree_host_impl_->GetDrawMode() ==
 703          DRAW_MODE_RESOURCELESS_SOFTWARE);
 704     size_t layers_updated_count = 0;
 705     bool tile_priorities_updated = false;
 706     for (PictureLayerImpl* layer : picture_layers_) {
 707       if (!layer->IsDrawnRenderSurfaceLayerListMember())
 708         continue;
 709       ++layers_updated_count;
 710       tile_priorities_updated |= layer->UpdateTiles(resourceless_software_draw);
 711     }
 712
 713     if (tile_priorities_updated)
 714       DidModifyTilePriorities();
 715
 716     TRACE_EVENT_END1("cc", "LayerTreeImpl::UpdateTilePriorities",
 717                      "layers_updated_count", layers_updated_count);
 718   }
 719
 720   DCHECK(!needs_update_draw_properties_) <<
 721       "CalcDrawProperties should not set_needs_update_draw_properties()";
 722   return true;
 723 }
 724
 725 void LayerTreeImpl::BuildPropertyTreesForTesting() {
 726   LayerTreeHostCommon::PreCalculateMetaInformationForTesting(root_layer_.get());
 727   PropertyTreeBuilder::BuildPropertyTrees(
 728       root_layer_.get(), PageScaleLayer(), InnerViewportScrollLayer(),
 729       OuterViewportScrollLayer(), current_page_scale_factor(),
 730       device_scale_factor(), gfx::Rect(DrawViewportSize()),
 731       layer_tree_host_impl_->DrawTransform(), &property_trees_);
 732 }
 733
 734 const LayerImplList& LayerTreeImpl::RenderSurfaceLayerList() const {
 735   // If this assert triggers, then the list is dirty.
 736   DCHECK(!needs_update_draw_properties_);
 737   return render_surface_layer_list_;
 738 }
 739
 740 const Region& LayerTreeImpl::UnoccludedScreenSpaceRegion() const {
 741   // If this assert triggers, then the render_surface_layer_list_ is dirty, so
 742   // the unoccluded_screen_space_region_ is not valid anymore.
 743   DCHECK(!needs_update_draw_properties_);
 744   return unoccluded_screen_space_region_;
 745 }
 746
 747 gfx::Size LayerTreeImpl::ScrollableSize() const {
 748   LayerImpl* root_scroll_layer = OuterViewportScrollLayer()
 749                                      ? OuterViewportScrollLayer()
 750                                      : InnerViewportScrollLayer();
 751   if (!root_scroll_layer || root_scroll_layer->children().empty())
 752     return gfx::Size();
 753   return root_scroll_layer->children()[0]->bounds();
 754 }
 755
 756 LayerImpl* LayerTreeImpl::LayerById(int id) const {
 757   LayerIdMap::const_iterator iter = layer_id_map_.find(id);
 758   return iter != layer_id_map_.end() ? iter->second : NULL;
 759 }
 760
 761 void LayerTreeImpl::RegisterLayer(LayerImpl* layer) {
 762   DCHECK(!LayerById(layer->id()));
 763   layer_id_map_[layer->id()] = layer;
 764   if (layer_tree_host_impl_->animation_host())
 765     layer_tree_host_impl_->animation_host()->RegisterLayer(
 766         layer->id(),
 767         IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING);
 768 }
 769
 770 void LayerTreeImpl::UnregisterLayer(LayerImpl* layer) {
 771   DCHECK(LayerById(layer->id()));
 772   if (layer_tree_host_impl_->animation_host())
 773     layer_tree_host_impl_->animation_host()->UnregisterLayer(
 774         layer->id(),
 775         IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING);
 776   layer_id_map_.erase(layer->id());
 777 }
 778
 779 size_t LayerTreeImpl::NumLayers() {
 780   return layer_id_map_.size();
 781 }
 782
 783 void LayerTreeImpl::DidBecomeActive() {
 784   if (next_activation_forces_redraw_) {
 785     layer_tree_host_impl_->SetFullRootLayerDamage();
 786     next_activation_forces_redraw_ = false;
 787   }
 788
 789   // Always reset this flag on activation, as we would only have activated
 790   // if we were in a good state.
 791   layer_tree_host_impl_->ResetRequiresHighResToDraw();
 792
 793   if (root_layer()) {
 794     LayerTreeHostCommon::CallFunctionForSubtree(
 795         root_layer(), [](LayerImpl* layer) { layer->DidBecomeActive(); });
 796   }
 797
 798   for (auto* swap_promise : swap_promise_list_)
 799     swap_promise->DidActivate();
 800   devtools_instrumentation::DidActivateLayerTree(layer_tree_host_impl_->id(),
 801                                                  source_frame_number_);
 802 }
 803
 804 bool LayerTreeImpl::RequiresHighResToDraw() const {
 805   return layer_tree_host_impl_->RequiresHighResToDraw();
 806 }
 807
 808 bool LayerTreeImpl::ViewportSizeInvalid() const {
 809   return viewport_size_invalid_;
 810 }
 811
 812 void LayerTreeImpl::SetViewportSizeInvalid() {
 813   viewport_size_invalid_ = true;
 814   layer_tree_host_impl_->OnCanDrawStateChangedForTree();
 815 }
 816
 817 void LayerTreeImpl::ResetViewportSizeInvalid() {
 818   viewport_size_invalid_ = false;
 819   layer_tree_host_impl_->OnCanDrawStateChangedForTree();
 820 }
 821
 822 Proxy* LayerTreeImpl::proxy() const {
 823   return layer_tree_host_impl_->proxy();
 824 }
 825
 826 const LayerTreeSettings& LayerTreeImpl::settings() const {
 827   return layer_tree_host_impl_->settings();
 828 }
 829
 830 const LayerTreeDebugState& LayerTreeImpl::debug_state() const {
 831   return layer_tree_host_impl_->debug_state();
 832 }
 833
 834 const RendererCapabilitiesImpl& LayerTreeImpl::GetRendererCapabilities() const {
 835   return layer_tree_host_impl_->GetRendererCapabilities();
 836 }
 837
 838 ContextProvider* LayerTreeImpl::context_provider() const {
 839   return output_surface()->context_provider();
 840 }
 841
 842 OutputSurface* LayerTreeImpl::output_surface() const {
 843   return layer_tree_host_impl_->output_surface();
 844 }
 845
 846 ResourceProvider* LayerTreeImpl::resource_provider() const {
 847   return layer_tree_host_impl_->resource_provider();
 848 }
 849
 850 TileManager* LayerTreeImpl::tile_manager() const {
 851   return layer_tree_host_impl_->tile_manager();
 852 }
 853
 854 FrameRateCounter* LayerTreeImpl::frame_rate_counter() const {
 855   return layer_tree_host_impl_->fps_counter();
 856 }
 857
 858 PaintTimeCounter* LayerTreeImpl::paint_time_counter() const {
 859   return layer_tree_host_impl_->paint_time_counter();
 860 }
 861
 862 MemoryHistory* LayerTreeImpl::memory_history() const {
 863   return layer_tree_host_impl_->memory_history();
 864 }
 865
 866 gfx::Size LayerTreeImpl::device_viewport_size() const {
 867   return layer_tree_host_impl_->device_viewport_size();
 868 }
 869
 870 float LayerTreeImpl::device_scale_factor() const {
 871   return layer_tree_host_impl_->device_scale_factor();
 872 }
 873
 874 DebugRectHistory* LayerTreeImpl::debug_rect_history() const {
 875   return layer_tree_host_impl_->debug_rect_history();
 876 }
 877
 878 bool LayerTreeImpl::IsActiveTree() const {
 879   return layer_tree_host_impl_->active_tree() == this;
 880 }
 881
 882 bool LayerTreeImpl::IsPendingTree() const {
 883   return layer_tree_host_impl_->pending_tree() == this;
 884 }
 885
 886 bool LayerTreeImpl::IsRecycleTree() const {
 887   return layer_tree_host_impl_->recycle_tree() == this;
 888 }
 889
 890 bool LayerTreeImpl::IsSyncTree() const {
 891   return layer_tree_host_impl_->sync_tree() == this;
 892 }
 893
 894 LayerImpl* LayerTreeImpl::FindActiveTreeLayerById(int id) {
 895   LayerTreeImpl* tree = layer_tree_host_impl_->active_tree();
 896   if (!tree)
 897     return NULL;
 898   return tree->LayerById(id);
 899 }
 900
 901 LayerImpl* LayerTreeImpl::FindPendingTreeLayerById(int id) {
 902   LayerTreeImpl* tree = layer_tree_host_impl_->pending_tree();
 903   if (!tree)
 904     return NULL;
 905   return tree->LayerById(id);
 906 }
 907
 908 bool LayerTreeImpl::PinchGestureActive() const {
 909   return layer_tree_host_impl_->pinch_gesture_active();
 910 }
 911
 912 BeginFrameArgs LayerTreeImpl::CurrentBeginFrameArgs() const {
 913   return layer_tree_host_impl_->CurrentBeginFrameArgs();
 914 }
 915
 916 base::TimeDelta LayerTreeImpl::CurrentBeginFrameInterval() const {
 917   return layer_tree_host_impl_->CurrentBeginFrameInterval();
 918 }
 919
 920 void LayerTreeImpl::SetNeedsCommit() {
 921   layer_tree_host_impl_->SetNeedsCommit();
 922 }
 923
 924 gfx::Rect LayerTreeImpl::DeviceViewport() const {
 925   return layer_tree_host_impl_->DeviceViewport();
 926 }
 927
 928 gfx::Size LayerTreeImpl::DrawViewportSize() const {
 929   return layer_tree_host_impl_->DrawViewportSize();
 930 }
 931
 932 const gfx::Rect LayerTreeImpl::ViewportRectForTilePriority() const {
 933   return layer_tree_host_impl_->ViewportRectForTilePriority();
 934 }
 935
 936 scoped_ptr<ScrollbarAnimationController>
 937 LayerTreeImpl::CreateScrollbarAnimationController(LayerImpl* scrolling_layer) {
 938   DCHECK(settings().scrollbar_fade_delay_ms);
 939   DCHECK(settings().scrollbar_fade_duration_ms);
 940   base::TimeDelta delay =
 941       base::TimeDelta::FromMilliseconds(settings().scrollbar_fade_delay_ms);
 942   base::TimeDelta resize_delay = base::TimeDelta::FromMilliseconds(
 943       settings().scrollbar_fade_resize_delay_ms);
 944   base::TimeDelta duration =
 945       base::TimeDelta::FromMilliseconds(settings().scrollbar_fade_duration_ms);
 946   switch (settings().scrollbar_animator) {
 947     case LayerTreeSettings::LINEAR_FADE: {
 948       return ScrollbarAnimationControllerLinearFade::Create(
 949           scrolling_layer,
 950           layer_tree_host_impl_,
 951           delay,
 952           resize_delay,
 953           duration);
 954     }
 955     case LayerTreeSettings::THINNING: {
 956       return ScrollbarAnimationControllerThinning::Create(scrolling_layer,
 957                                                           layer_tree_host_impl_,
 958                                                           delay,
 959                                                           resize_delay,
 960                                                           duration);
 961     }
 962     case LayerTreeSettings::NO_ANIMATOR:
 963       NOTREACHED();
 964       break;
 965   }
 966   return nullptr;
 967 }
 968
 969 void LayerTreeImpl::DidAnimateScrollOffset() {
 970   layer_tree_host_impl_->DidAnimateScrollOffset();
 971 }
 972
 973 bool LayerTreeImpl::use_gpu_rasterization() const {
 974   return layer_tree_host_impl_->use_gpu_rasterization();
 975 }
 976
 977 GpuRasterizationStatus LayerTreeImpl::GetGpuRasterizationStatus() const {
 978   return layer_tree_host_impl_->gpu_rasterization_status();
 979 }
 980
 981 bool LayerTreeImpl::create_low_res_tiling() const {
 982   return layer_tree_host_impl_->create_low_res_tiling();
 983 }
 984
 985 void LayerTreeImpl::SetNeedsRedraw() {
 986   layer_tree_host_impl_->SetNeedsRedraw();
 987 }
 988
 989 AnimationRegistrar* LayerTreeImpl::GetAnimationRegistrar() const {
 990   return layer_tree_host_impl_->animation_registrar();
 991 }
 992
 993 void LayerTreeImpl::GetAllPrioritizedTilesForTracing(
 994     std::vector<PrioritizedTile>* prioritized_tiles) const {
 995   LayerIterator end = LayerIterator::End(&render_surface_layer_list_);
 996   for (LayerIterator it = LayerIterator::Begin(&render_surface_layer_list_);
 997        it != end; ++it) {
 998     if (!it.represents_itself())
 999       continue;
1000     LayerImpl* layer_impl = *it;
1001     layer_impl->GetAllPrioritizedTilesForTracing(prioritized_tiles);
1002   }
1003 }
1004
1005 void LayerTreeImpl::AsValueInto(base::trace_event::TracedValue* state) const {
1006   TracedValue::MakeDictIntoImplicitSnapshot(state, "cc::LayerTreeImpl", this);
1007   state->SetInteger("source_frame_number", source_frame_number_);
1008
1009   state->BeginDictionary("root_layer");
1010   root_layer_->AsValueInto(state);
1011   state->EndDictionary();
1012
1013   state->BeginArray("render_surface_layer_list");
1014   LayerIterator end = LayerIterator::End(&render_surface_layer_list_);
1015   for (LayerIterator it = LayerIterator::Begin(&render_surface_layer_list_);
1016        it != end; ++it) {
1017     if (!it.represents_itself())
1018       continue;
1019     TracedValue::AppendIDRef(*it, state);
1020   }
1021   state->EndArray();
1022
1023   state->BeginArray("swap_promise_trace_ids");
1024   for (auto* swap_promise : swap_promise_list_)
1025     state->AppendDouble(swap_promise->TraceId());
1026   state->EndArray();
1027 }
1028
1029 void LayerTreeImpl::SetRootLayerScrollOffsetDelegate(
1030     LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) {
1031   if (root_layer_scroll_offset_delegate_ == root_layer_scroll_offset_delegate)
1032     return;
1033
1034   root_layer_scroll_offset_delegate_ = root_layer_scroll_offset_delegate;
1035
1036   if (root_layer_scroll_offset_delegate_) {
1037     root_layer_scroll_offset_delegate_->UpdateRootLayerState(
1038         TotalScrollOffset(), TotalMaxScrollOffset(), ScrollableSize(),
1039         current_page_scale_factor(), min_page_scale_factor(),
1040         max_page_scale_factor());
1041
1042     DistributeRootScrollOffset();
1043   }
1044 }
1045
1046 void LayerTreeImpl::UpdateRootScrollOffsetDelegate() {
1047   DCHECK(root_layer_scroll_offset_delegate_);
1048
1049   gfx::ScrollOffset offset = InnerViewportScrollLayer()->CurrentScrollOffset();
1050
1051   if (OuterViewportScrollLayer())
1052     offset += OuterViewportScrollLayer()->CurrentScrollOffset();
1053
1054   root_layer_scroll_offset_delegate_->UpdateRootLayerState(
1055       offset, TotalMaxScrollOffset(), ScrollableSize(),
1056       current_page_scale_factor(), min_page_scale_factor(),
1057       max_page_scale_factor());
1058 }
1059
1060 void LayerTreeImpl::DistributeRootScrollOffset() {
1061   if (!root_layer_scroll_offset_delegate_)
1062     return;
1063
1064   gfx::ScrollOffset root_offset =
1065       root_layer_scroll_offset_delegate_->GetTotalScrollOffset();
1066
1067   if (!InnerViewportScrollLayer())
1068     return;
1069
1070   DCHECK(OuterViewportScrollLayer());
1071
1072   // If we get here, we have both inner/outer viewports, and need to distribute
1073   // the scroll offset between them.
1074   gfx::ScrollOffset inner_viewport_offset =
1075       InnerViewportScrollLayer()->CurrentScrollOffset();
1076   gfx::ScrollOffset outer_viewport_offset =
1077       OuterViewportScrollLayer()->CurrentScrollOffset();
1078
1079   // It may be nothing has changed.
1080   if (inner_viewport_offset + outer_viewport_offset == root_offset)
1081     return;
1082
1083   gfx::ScrollOffset max_outer_viewport_scroll_offset =
1084       OuterViewportScrollLayer()->MaxScrollOffset();
1085
1086   outer_viewport_offset = root_offset - inner_viewport_offset;
1087   outer_viewport_offset.SetToMin(max_outer_viewport_scroll_offset);
1088   outer_viewport_offset.SetToMax(gfx::ScrollOffset());
1089
1090   OuterViewportScrollLayer()->SetCurrentScrollOffsetFromDelegate(
1091       outer_viewport_offset);
1092   inner_viewport_offset = root_offset - outer_viewport_offset;
1093   InnerViewportScrollLayer()->SetCurrentScrollOffsetFromDelegate(
1094       inner_viewport_offset);
1095
1096   UpdateRootScrollOffsetDelegate();
1097 }
1098
1099 void LayerTreeImpl::QueueSwapPromise(scoped_ptr<SwapPromise> swap_promise) {
1100   DCHECK(swap_promise);
1101   swap_promise_list_.push_back(swap_promise.Pass());
1102 }
1103
1104 void LayerTreeImpl::PassSwapPromises(
1105     ScopedPtrVector<SwapPromise>* new_swap_promise) {
1106   swap_promise_list_.insert_and_take(swap_promise_list_.end(),
1107                                      new_swap_promise);
1108   new_swap_promise->clear();
1109 }
1110
1111 void LayerTreeImpl::FinishSwapPromises(CompositorFrameMetadata* metadata) {
1112   for (auto* swap_promise : swap_promise_list_)
1113     swap_promise->DidSwap(metadata);
1114   swap_promise_list_.clear();
1115 }
1116
1117 void LayerTreeImpl::BreakSwapPromises(SwapPromise::DidNotSwapReason reason) {
1118   for (auto* swap_promise : swap_promise_list_)
1119     swap_promise->DidNotSwap(reason);
1120   swap_promise_list_.clear();
1121 }
1122
1123 void LayerTreeImpl::DidModifyTilePriorities() {
1124   layer_tree_host_impl_->DidModifyTilePriorities();
1125 }
1126
1127 void LayerTreeImpl::set_ui_resource_request_queue(
1128     const UIResourceRequestQueue& queue) {
1129   ui_resource_request_queue_ = queue;
1130 }
1131
1132 ResourceId LayerTreeImpl::ResourceIdForUIResource(UIResourceId uid) const {
1133   return layer_tree_host_impl_->ResourceIdForUIResource(uid);
1134 }
1135
1136 bool LayerTreeImpl::IsUIResourceOpaque(UIResourceId uid) const {
1137   return layer_tree_host_impl_->IsUIResourceOpaque(uid);
1138 }
1139
1140 void LayerTreeImpl::ProcessUIResourceRequestQueue() {
1141   for (const auto& req : ui_resource_request_queue_) {
1142     switch (req.GetType()) {
1143       case UIResourceRequest::UI_RESOURCE_CREATE:
1144         layer_tree_host_impl_->CreateUIResource(req.GetId(), req.GetBitmap());
1145         break;
1146       case UIResourceRequest::UI_RESOURCE_DELETE:
1147         layer_tree_host_impl_->DeleteUIResource(req.GetId());
1148         break;
1149       case UIResourceRequest::UI_RESOURCE_INVALID_REQUEST:
1150         NOTREACHED();
1151         break;
1152     }
1153   }
1154   ui_resource_request_queue_.clear();
1155
1156   // If all UI resource evictions were not recreated by processing this queue,
1157   // then another commit is required.
1158   if (layer_tree_host_impl_->EvictedUIResourcesExist())
1159     layer_tree_host_impl_->SetNeedsCommit();
1160 }
1161
1162 void LayerTreeImpl::RegisterPictureLayerImpl(PictureLayerImpl* layer) {
1163   DCHECK(std::find(picture_layers_.begin(), picture_layers_.end(), layer) ==
1164          picture_layers_.end());
1165   picture_layers_.push_back(layer);
1166 }
1167
1168 void LayerTreeImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
1169   std::vector<PictureLayerImpl*>::iterator it =
1170       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
1171   DCHECK(it != picture_layers_.end());
1172   picture_layers_.erase(it);
1173 }
1174
1175 void LayerTreeImpl::AddLayerWithCopyOutputRequest(LayerImpl* layer) {
1176   // Only the active tree needs to know about layers with copy requests, as
1177   // they are aborted if not serviced during draw.
1178   DCHECK(IsActiveTree());
1179
1180   // DCHECK(std::find(layers_with_copy_output_request_.begin(),
1181   //                 layers_with_copy_output_request_.end(),
1182   //                 layer) == layers_with_copy_output_request_.end());
1183   // TODO(danakj): Remove this once crash is found crbug.com/309777
1184   for (size_t i = 0; i < layers_with_copy_output_request_.size(); ++i) {
1185     CHECK(layers_with_copy_output_request_[i] != layer)
1186         << i << " of " << layers_with_copy_output_request_.size();
1187   }
1188   layers_with_copy_output_request_.push_back(layer);
1189 }
1190
1191 void LayerTreeImpl::RemoveLayerWithCopyOutputRequest(LayerImpl* layer) {
1192   // Only the active tree needs to know about layers with copy requests, as
1193   // they are aborted if not serviced during draw.
1194   DCHECK(IsActiveTree());
1195
1196   std::vector<LayerImpl*>::iterator it = std::find(
1197       layers_with_copy_output_request_.begin(),
1198       layers_with_copy_output_request_.end(),
1199       layer);
1200   DCHECK(it != layers_with_copy_output_request_.end());
1201   layers_with_copy_output_request_.erase(it);
1202
1203   // TODO(danakj): Remove this once crash is found crbug.com/309777
1204   for (size_t i = 0; i < layers_with_copy_output_request_.size(); ++i) {
1205     CHECK(layers_with_copy_output_request_[i] != layer)
1206         << i << " of " << layers_with_copy_output_request_.size();
1207   }
1208 }
1209
1210 const std::vector<LayerImpl*>& LayerTreeImpl::LayersWithCopyOutputRequest()
1211     const {
1212   // Only the active tree needs to know about layers with copy requests, as
1213   // they are aborted if not serviced during draw.
1214   DCHECK(IsActiveTree());
1215
1216   return layers_with_copy_output_request_;
1217 }
1218
1219 template <typename LayerType>
1220 static inline bool LayerClipsSubtree(LayerType* layer) {
1221   return layer->masks_to_bounds() || layer->mask_layer();
1222 }
1223
1224 static bool PointHitsRect(
1225     const gfx::PointF& screen_space_point,
1226     const gfx::Transform& local_space_to_screen_space_transform,
1227     const gfx::RectF& local_space_rect,
1228     float* distance_to_camera) {
1229   // If the transform is not invertible, then assume that this point doesn't hit
1230   // this rect.
1231   gfx::Transform inverse_local_space_to_screen_space(
1232       gfx::Transform::kSkipInitialization);
1233   if (!local_space_to_screen_space_transform.GetInverse(
1234           &inverse_local_space_to_screen_space))
1235     return false;
1236
1237   // Transform the hit test point from screen space to the local space of the
1238   // given rect.
1239   bool clipped = false;
1240   gfx::Point3F planar_point = MathUtil::ProjectPoint3D(
1241       inverse_local_space_to_screen_space, screen_space_point, &clipped);
1242   gfx::PointF hit_test_point_in_local_space =
1243       gfx::PointF(planar_point.x(), planar_point.y());
1244
1245   // If ProjectPoint could not project to a valid value, then we assume that
1246   // this point doesn't hit this rect.
1247   if (clipped)
1248     return false;
1249
1250   if (!local_space_rect.Contains(hit_test_point_in_local_space))
1251     return false;
1252
1253   if (distance_to_camera) {
1254     // To compute the distance to the camera, we have to take the planar point
1255     // and pull it back to world space and compute the displacement along the
1256     // z-axis.
1257     gfx::Point3F planar_point_in_screen_space(planar_point);
1258     local_space_to_screen_space_transform.TransformPoint(
1259         &planar_point_in_screen_space);
1260     *distance_to_camera = planar_point_in_screen_space.z();
1261   }
1262
1263   return true;
1264 }
1265
1266 static bool PointHitsRegion(const gfx::PointF& screen_space_point,
1267                             const gfx::Transform& screen_space_transform,
1268                             const Region& layer_space_region) {
1269   // If the transform is not invertible, then assume that this point doesn't hit
1270   // this region.
1271   gfx::Transform inverse_screen_space_transform(
1272       gfx::Transform::kSkipInitialization);
1273   if (!screen_space_transform.GetInverse(&inverse_screen_space_transform))
1274     return false;
1275
1276   // Transform the hit test point from screen space to the local space of the
1277   // given region.
1278   bool clipped = false;
1279   gfx::PointF hit_test_point_in_layer_space = MathUtil::ProjectPoint(
1280       inverse_screen_space_transform, screen_space_point, &clipped);
1281
1282   // If ProjectPoint could not project to a valid value, then we assume that
1283   // this point doesn't hit this region.
1284   if (clipped)
1285     return false;
1286
1287   return layer_space_region.Contains(
1288       gfx::ToRoundedPoint(hit_test_point_in_layer_space));
1289 }
1290
1291 static const LayerImpl* GetNextClippingLayer(const LayerImpl* layer) {
1292   if (layer->scroll_parent())
1293     return layer->scroll_parent();
1294   if (layer->clip_parent())
1295     return layer->clip_parent();
1296   return layer->parent();
1297 }
1298
1299 static bool PointIsClippedBySurfaceOrClipRect(
1300     const gfx::PointF& screen_space_point,
1301     const LayerImpl* layer) {
1302   // Walk up the layer tree and hit-test any render_surfaces and any layer
1303   // clip rects that are active.
1304   for (; layer; layer = GetNextClippingLayer(layer)) {
1305     if (layer->render_surface() &&
1306         !PointHitsRect(screen_space_point,
1307                        layer->render_surface()->screen_space_transform(),
1308                        layer->render_surface()->content_rect(),
1309                        NULL))
1310       return true;
1311
1312     if (LayerClipsSubtree(layer) &&
1313         !PointHitsRect(screen_space_point, layer->screen_space_transform(),
1314                        gfx::Rect(layer->bounds()), NULL))
1315       return true;
1316   }
1317
1318   // If we have finished walking all ancestors without having already exited,
1319   // then the point is not clipped by any ancestors.
1320   return false;
1321 }
1322
1323 static bool PointHitsLayer(const LayerImpl* layer,
1324                            const gfx::PointF& screen_space_point,
1325                            float* distance_to_intersection) {
1326   gfx::RectF content_rect(layer->bounds());
1327   if (!PointHitsRect(screen_space_point,
1328                      layer->screen_space_transform(),
1329                      content_rect,
1330                      distance_to_intersection))
1331     return false;
1332
1333   // At this point, we think the point does hit the layer, but we need to walk
1334   // up the parents to ensure that the layer was not clipped in such a way
1335   // that the hit point actually should not hit the layer.
1336   if (PointIsClippedBySurfaceOrClipRect(screen_space_point, layer))
1337     return false;
1338
1339   // Skip the HUD layer.
1340   if (layer == layer->layer_tree_impl()->hud_layer())
1341     return false;
1342
1343   return true;
1344 }
1345
1346 struct FindClosestMatchingLayerDataForRecursion {
1347   FindClosestMatchingLayerDataForRecursion()
1348       : closest_match(NULL),
1349         closest_distance(-std::numeric_limits<float>::infinity()) {}
1350   LayerImpl* closest_match;
1351   // Note that the positive z-axis points towards the camera, so bigger means
1352   // closer in this case, counterintuitively.
1353   float closest_distance;
1354 };
1355
1356 template <typename Functor>
1357 static void FindClosestMatchingLayer(
1358     const gfx::PointF& screen_space_point,
1359     LayerImpl* layer,
1360     const Functor& func,
1361     FindClosestMatchingLayerDataForRecursion* data_for_recursion) {
1362   size_t children_size = layer->children().size();
1363   for (size_t i = 0; i < children_size; ++i) {
1364     size_t index = children_size - 1 - i;
1365     FindClosestMatchingLayer(screen_space_point, layer->children()[index], func,
1366                              data_for_recursion);
1367   }
1368
1369   float distance_to_intersection = 0.f;
1370   if (func(layer) &&
1371       PointHitsLayer(layer, screen_space_point, &distance_to_intersection) &&
1372       ((!data_for_recursion->closest_match ||
1373         distance_to_intersection > data_for_recursion->closest_distance))) {
1374     data_for_recursion->closest_distance = distance_to_intersection;
1375     data_for_recursion->closest_match = layer;
1376   }
1377 }
1378
1379 static bool ScrollsAnyDrawnRenderSurfaceLayerListMember(LayerImpl* layer) {
1380   if (!layer->scrollable())
1381     return false;
1382   if (layer->layer_or_descendant_is_drawn())
1383     return true;
1384
1385   if (!layer->scroll_children())
1386     return false;
1387   for (std::set<LayerImpl*>::const_iterator it =
1388            layer->scroll_children()->begin();
1389        it != layer->scroll_children()->end();
1390        ++it) {
1391     if ((*it)->layer_or_descendant_is_drawn())
1392       return true;
1393   }
1394   return false;
1395 }
1396
1397 struct FindScrollingLayerFunctor {
1398   bool operator()(LayerImpl* layer) const {
1399     return ScrollsAnyDrawnRenderSurfaceLayerListMember(layer);
1400   }
1401 };
1402
1403 LayerImpl* LayerTreeImpl::FindFirstScrollingLayerThatIsHitByPoint(
1404     const gfx::PointF& screen_space_point) {
1405   FindClosestMatchingLayerDataForRecursion data_for_recursion;
1406   FindClosestMatchingLayer(screen_space_point,
1407                            root_layer(),
1408                            FindScrollingLayerFunctor(),
1409                            &data_for_recursion);
1410   return data_for_recursion.closest_match;
1411 }
1412
1413 struct HitTestVisibleScrollableOrTouchableFunctor {
1414   bool operator()(LayerImpl* layer) const {
1415     return layer->IsDrawnRenderSurfaceLayerListMember() ||
1416            ScrollsAnyDrawnRenderSurfaceLayerListMember(layer) ||
1417            !layer->touch_event_handler_region().IsEmpty() ||
1418            layer->have_wheel_event_handlers();
1419   }
1420 };
1421
1422 LayerImpl* LayerTreeImpl::FindLayerThatIsHitByPoint(
1423     const gfx::PointF& screen_space_point) {
1424   if (!root_layer())
1425     return NULL;
1426   bool update_lcd_text = false;
1427   if (!UpdateDrawProperties(update_lcd_text))
1428     return NULL;
1429   FindClosestMatchingLayerDataForRecursion data_for_recursion;
1430   FindClosestMatchingLayer(screen_space_point,
1431                            root_layer(),
1432                            HitTestVisibleScrollableOrTouchableFunctor(),
1433                            &data_for_recursion);
1434   return data_for_recursion.closest_match;
1435 }
1436
1437 static bool LayerHasTouchEventHandlersAt(const gfx::PointF& screen_space_point,
1438                                          LayerImpl* layer_impl) {
1439   if (layer_impl->touch_event_handler_region().IsEmpty())
1440     return false;
1441
1442   if (!PointHitsRegion(screen_space_point, layer_impl->screen_space_transform(),
1443                        layer_impl->touch_event_handler_region()))
1444     return false;
1445
1446   // At this point, we think the point does hit the touch event handler region
1447   // on the layer, but we need to walk up the parents to ensure that the layer
1448   // was not clipped in such a way that the hit point actually should not hit
1449   // the layer.
1450   if (PointIsClippedBySurfaceOrClipRect(screen_space_point, layer_impl))
1451     return false;
1452
1453   return true;
1454 }
1455
1456 struct FindWheelEventLayerFunctor {
1457   bool operator()(LayerImpl* layer) const {
1458     return layer->have_wheel_event_handlers();
1459   }
1460 };
1461
1462 LayerImpl* LayerTreeImpl::FindLayerWithWheelHandlerThatIsHitByPoint(
1463     const gfx::PointF& screen_space_point) {
1464   if (!root_layer())
1465     return NULL;
1466   bool update_lcd_text = false;
1467   if (!UpdateDrawProperties(update_lcd_text))
1468     return NULL;
1469   FindWheelEventLayerFunctor func;
1470   FindClosestMatchingLayerDataForRecursion data_for_recursion;
1471   FindClosestMatchingLayer(screen_space_point, root_layer(), func,
1472                            &data_for_recursion);
1473   return data_for_recursion.closest_match;
1474 }
1475
1476 struct FindTouchEventLayerFunctor {
1477   bool operator()(LayerImpl* layer) const {
1478     return LayerHasTouchEventHandlersAt(screen_space_point, layer);
1479   }
1480   const gfx::PointF screen_space_point;
1481 };
1482
1483 LayerImpl* LayerTreeImpl::FindLayerThatIsHitByPointInTouchHandlerRegion(
1484     const gfx::PointF& screen_space_point) {
1485   if (!root_layer())
1486     return NULL;
1487   bool update_lcd_text = false;
1488   if (!UpdateDrawProperties(update_lcd_text))
1489     return NULL;
1490   FindTouchEventLayerFunctor func = {screen_space_point};
1491   FindClosestMatchingLayerDataForRecursion data_for_recursion;
1492   FindClosestMatchingLayer(
1493       screen_space_point, root_layer(), func, &data_for_recursion);
1494   return data_for_recursion.closest_match;
1495 }
1496
1497 void LayerTreeImpl::RegisterSelection(const LayerSelection& selection) {
1498   selection_ = selection;
1499 }
1500
1501 static ViewportSelectionBound ComputeViewportSelectionBound(
1502     const LayerSelectionBound& layer_bound,
1503     LayerImpl* layer,
1504     float device_scale_factor) {
1505   ViewportSelectionBound viewport_bound;
1506   viewport_bound.type = layer_bound.type;
1507
1508   if (!layer || layer_bound.type == SELECTION_BOUND_EMPTY)
1509     return viewport_bound;
1510
1511   gfx::PointF layer_top = layer_bound.edge_top;
1512   gfx::PointF layer_bottom = layer_bound.edge_bottom;
1513
1514   bool clipped = false;
1515   gfx::PointF screen_top =
1516       MathUtil::MapPoint(layer->screen_space_transform(), layer_top, &clipped);
1517   gfx::PointF screen_bottom = MathUtil::MapPoint(
1518       layer->screen_space_transform(), layer_bottom, &clipped);
1519
1520   const float inv_scale = 1.f / device_scale_factor;
1521   viewport_bound.edge_top = gfx::ScalePoint(screen_top, inv_scale);
1522   viewport_bound.edge_bottom = gfx::ScalePoint(screen_bottom, inv_scale);
1523
1524   // The bottom edge point is used for visibility testing as it is the logical
1525   // focal point for bound selection handles (this may change in the future).
1526   // Shifting the visibility point fractionally inward ensures that neighboring
1527   // or logically coincident layers aligned to integral DPI coordinates will not
1528   // spuriously occlude the bound.
1529   gfx::Vector2dF visibility_offset = layer_top - layer_bottom;
1530   visibility_offset.Scale(device_scale_factor / visibility_offset.Length());
1531   gfx::PointF visibility_point = layer_bottom + visibility_offset;
1532   if (visibility_point.x() <= 0)
1533     visibility_point.set_x(visibility_point.x() + device_scale_factor);
1534   visibility_point = MathUtil::MapPoint(
1535       layer->screen_space_transform(), visibility_point, &clipped);
1536
1537   float intersect_distance = 0.f;
1538   viewport_bound.visible =
1539       PointHitsLayer(layer, visibility_point, &intersect_distance);
1540
1541   return viewport_bound;
1542 }
1543
1544 void LayerTreeImpl::GetViewportSelection(ViewportSelection* selection) {
1545   DCHECK(selection);
1546
1547   selection->start = ComputeViewportSelectionBound(
1548       selection_.start,
1549       selection_.start.layer_id ? LayerById(selection_.start.layer_id) : NULL,
1550       device_scale_factor());
1551   selection->is_editable = selection_.is_editable;
1552   selection->is_empty_text_form_control = selection_.is_empty_text_form_control;
1553   if (selection->start.type == SELECTION_BOUND_CENTER ||
1554       selection->start.type == SELECTION_BOUND_EMPTY) {
1555     selection->end = selection->start;
1556   } else {
1557     selection->end = ComputeViewportSelectionBound(
1558         selection_.end,
1559         selection_.end.layer_id ? LayerById(selection_.end.layer_id) : NULL,
1560         device_scale_factor());
1561   }
1562 }
1563
1564 void LayerTreeImpl::InputScrollAnimationFinished() {
1565   layer_tree_host_impl_->ScrollEnd();
1566 }
1567
1568 bool LayerTreeImpl::SmoothnessTakesPriority() const {
1569   return layer_tree_host_impl_->GetTreePriority() == SMOOTHNESS_TAKES_PRIORITY;
1570 }
1571
1572 BlockingTaskRunner* LayerTreeImpl::BlockingMainThreadTaskRunner() const {
1573   return proxy()->blocking_main_thread_task_runner();
1574 }
1575
1576 VideoFrameControllerClient* LayerTreeImpl::GetVideoFrameControllerClient()
1577     const {
1578   return layer_tree_host_impl_;
1579 }
1580
1581 void LayerTreeImpl::SetPendingPageScaleAnimation(
1582     scoped_ptr<PendingPageScaleAnimation> pending_animation) {
1583   pending_page_scale_animation_ = pending_animation.Pass();
1584 }
1585
1586 scoped_ptr<PendingPageScaleAnimation>
1587     LayerTreeImpl::TakePendingPageScaleAnimation() {
1588   return pending_page_scale_animation_.Pass();
1589 }
1590
1591 bool LayerTreeImpl::IsAnimatingFilterProperty(const LayerImpl* layer) const {
1592   LayerTreeType tree_type =
1593       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1594   return layer_tree_host_impl_->animation_host()
1595              ? layer_tree_host_impl_->animation_host()
1596                    ->IsAnimatingFilterProperty(layer->id(), tree_type)
1597              : false;
1598 }
1599
1600 bool LayerTreeImpl::IsAnimatingOpacityProperty(const LayerImpl* layer) const {
1601   LayerTreeType tree_type =
1602       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1603   return layer_tree_host_impl_->animation_host()
1604              ? layer_tree_host_impl_->animation_host()
1605                    ->IsAnimatingOpacityProperty(layer->id(), tree_type)
1606              : false;
1607 }
1608
1609 bool LayerTreeImpl::IsAnimatingTransformProperty(const LayerImpl* layer) const {
1610   LayerTreeType tree_type =
1611       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1612   return layer_tree_host_impl_->animation_host()
1613              ? layer_tree_host_impl_->animation_host()
1614                    ->IsAnimatingTransformProperty(layer->id(), tree_type)
1615              : false;
1616 }
1617
1618 bool LayerTreeImpl::HasPotentiallyRunningFilterAnimation(
1619     const LayerImpl* layer) const {
1620   LayerTreeType tree_type =
1621       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1622   return layer_tree_host_impl_->animation_host()
1623              ? layer_tree_host_impl_->animation_host()
1624                    ->HasPotentiallyRunningFilterAnimation(layer->id(),
1625                                                           tree_type)
1626              : false;
1627 }
1628
1629 bool LayerTreeImpl::HasPotentiallyRunningOpacityAnimation(
1630     const LayerImpl* layer) const {
1631   LayerTreeType tree_type =
1632       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1633   return layer_tree_host_impl_->animation_host()
1634              ? layer_tree_host_impl_->animation_host()
1635                    ->HasPotentiallyRunningOpacityAnimation(layer->id(),
1636                                                            tree_type)
1637              : false;
1638 }
1639
1640 bool LayerTreeImpl::HasPotentiallyRunningTransformAnimation(
1641     const LayerImpl* layer) const {
1642   LayerTreeType tree_type =
1643       IsActiveTree() ? LayerTreeType::ACTIVE : LayerTreeType::PENDING;
1644   return layer_tree_host_impl_->animation_host()
1645              ? layer_tree_host_impl_->animation_host()
1646                    ->HasPotentiallyRunningTransformAnimation(layer->id(),
1647                                                              tree_type)
1648              : false;
1649 }
1650
1651 bool LayerTreeImpl::HasAnyAnimationTargetingProperty(
1652     const LayerImpl* layer,
1653     Animation::TargetProperty property) const {
1654   return layer_tree_host_impl_->animation_host()
1655              ? layer_tree_host_impl_->animation_host()
1656                    ->HasAnyAnimationTargetingProperty(layer->id(), property)
1657              : false;
1658 }
1659
1660 bool LayerTreeImpl::FilterIsAnimatingOnImplOnly(const LayerImpl* layer) const {
1661   return layer_tree_host_impl_->animation_host()
1662              ? layer_tree_host_impl_->animation_host()
1663                    ->FilterIsAnimatingOnImplOnly(layer->id())
1664              : false;
1665 }
1666
1667 bool LayerTreeImpl::OpacityIsAnimatingOnImplOnly(const LayerImpl* layer) const {
1668   return layer_tree_host_impl_->animation_host()
1669              ? layer_tree_host_impl_->animation_host()
1670                    ->OpacityIsAnimatingOnImplOnly(layer->id())
1671              : false;
1672 }
1673
1674 bool LayerTreeImpl::TransformIsAnimatingOnImplOnly(
1675     const LayerImpl* layer) const {
1676   return layer_tree_host_impl_->animation_host()
1677              ? layer_tree_host_impl_->animation_host()
1678                    ->TransformIsAnimatingOnImplOnly(layer->id())
1679              : false;
1680 }
1681
1682 bool LayerTreeImpl::HasOnlyTranslationTransforms(const LayerImpl* layer) const {
1683   return layer_tree_host_impl_->animation_host()
1684              ? layer_tree_host_impl_->animation_host()
1685                    ->HasOnlyTranslationTransforms(layer->id())
1686              : true;
1687 }
1688
1689 bool LayerTreeImpl::MaximumTargetScale(const LayerImpl* layer,
1690                                        float* max_scale) const {
1691   *max_scale = 0.f;
1692   return layer_tree_host_impl_->animation_host()
1693              ? layer_tree_host_impl_->animation_host()->MaximumTargetScale(
1694                    layer->id(), max_scale)
1695              : true;
1696 }
1697
1698 bool LayerTreeImpl::AnimationStartScale(const LayerImpl* layer,
1699                                         float* start_scale) const {
1700   *start_scale = 0.f;
1701   return layer_tree_host_impl_->animation_host()
1702              ? layer_tree_host_impl_->animation_host()->AnimationStartScale(
1703                    layer->id(), start_scale)
1704              : true;
1705 }
1706
1707 bool LayerTreeImpl::HasFilterAnimationThatInflatesBounds(
1708     const LayerImpl* layer) const {
1709   return layer_tree_host_impl_->animation_host()
1710              ? layer_tree_host_impl_->animation_host()
1711                    ->HasFilterAnimationThatInflatesBounds(layer->id())
1712              : false;
1713 }
1714
1715 bool LayerTreeImpl::HasTransformAnimationThatInflatesBounds(
1716     const LayerImpl* layer) const {
1717   return layer_tree_host_impl_->animation_host()
1718              ? layer_tree_host_impl_->animation_host()
1719                    ->HasTransformAnimationThatInflatesBounds(layer->id())
1720              : false;
1721 }
1722
1723 bool LayerTreeImpl::HasAnimationThatInflatesBounds(
1724     const LayerImpl* layer) const {
1725   return layer_tree_host_impl_->animation_host()
1726              ? layer_tree_host_impl_->animation_host()
1727                    ->HasAnimationThatInflatesBounds(layer->id())
1728              : false;
1729 }
1730
1731 bool LayerTreeImpl::FilterAnimationBoundsForBox(const LayerImpl* layer,
1732                                                 const gfx::BoxF& box,
1733                                                 gfx::BoxF* bounds) const {
1734   return layer_tree_host_impl_->animation_host()
1735              ? layer_tree_host_impl_->animation_host()
1736                    ->FilterAnimationBoundsForBox(layer->id(), box, bounds)
1737              : false;
1738 }
1739
1740 bool LayerTreeImpl::TransformAnimationBoundsForBox(const LayerImpl* layer,
1741                                                    const gfx::BoxF& box,
1742                                                    gfx::BoxF* bounds) const {
1743   *bounds = gfx::BoxF();
1744   return layer_tree_host_impl_->animation_host()
1745              ? layer_tree_host_impl_->animation_host()
1746                    ->TransformAnimationBoundsForBox(layer->id(), box, bounds)
1747              : true;
1748 }
1749
1750 }  // namespace cc