cc/trees/draw_property_utils.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 "cc/trees/draw_property_utils.h"
   6
   7 #include <vector>
   8
   9 #include "cc/base/math_util.h"
  10 #include "cc/layers/layer.h"
  11 #include "cc/layers/layer_impl.h"
  12 #include "cc/trees/layer_tree_impl.h"
  13 #include "cc/trees/property_tree.h"
  14 #include "cc/trees/property_tree_builder.h"
  15 #include "ui/gfx/geometry/rect_conversions.h"
  16
  17 namespace cc {
  18
  19 namespace {
  20
  21 template <typename LayerType>
  22 void CalculateVisibleRects(const std::vector<LayerType*>& visible_layer_list,
  23                            const ClipTree& clip_tree,
  24                            const TransformTree& transform_tree) {
  25   for (auto& layer : visible_layer_list) {
  26     // TODO(ajuma): Compute content_scale rather than using it. Note that for
  27     // PictureLayer and PictureImageLayers, content_bounds == bounds and
  28     // content_scale_x == content_scale_y == 1.0, so once impl painting is on
  29     // everywhere, this code will be unnecessary.
  30     gfx::Size layer_bounds = layer->bounds();
  31     const bool has_clip = layer->clip_tree_index() > 0;
  32     const TransformNode* transform_node =
  33         transform_tree.Node(layer->transform_tree_index());
  34     if (has_clip) {
  35       const ClipNode* clip_node = clip_tree.Node(layer->clip_tree_index());
  36       const TransformNode* clip_transform_node =
  37           transform_tree.Node(clip_node->data.transform_id);
  38       const bool target_is_root_surface =
  39           transform_node->data.content_target_id == 1;
  40       // When the target is the root surface, we need to include the root
  41       // transform by walking up to the root of the transform tree.
  42       const int target_id =
  43           target_is_root_surface ? 0 : transform_node->data.content_target_id;
  44       const TransformNode* target_node = transform_tree.Node(target_id);
  45
  46       gfx::Transform content_to_target = transform_node->data.to_target;
  47
  48       content_to_target.Translate(layer->offset_to_transform_parent().x(),
  49                                   layer->offset_to_transform_parent().y());
  50
  51       gfx::Rect combined_clip_rect_in_target_space;
  52       gfx::Rect clip_rect_in_target_space;
  53       gfx::Transform clip_to_target;
  54       bool success = true;
  55       if (clip_transform_node->data.target_id == target_node->id) {
  56         clip_to_target = clip_transform_node->data.to_target;
  57       } else {
  58         success = transform_tree.ComputeTransformWithDestinationSublayerScale(
  59             clip_transform_node->id, target_node->id, &clip_to_target);
  60       }
  61       if (target_node->id > clip_node->data.transform_id) {
  62         if (!success) {
  63           DCHECK(target_node->data.to_screen_is_animated);
  64
  65           // An animated singular transform may become non-singular during the
  66           // animation, so we still need to compute a visible rect. In this
  67           // situation, we treat the entire layer as visible.
  68           layer->set_visible_rect_from_property_trees(gfx::Rect(layer_bounds));
  69           layer->set_clip_rect_in_target_space_from_property_trees(
  70               gfx::ToEnclosingRect(clip_node->data.combined_clip));
  71           continue;
  72         }
  73
  74         combined_clip_rect_in_target_space =
  75             gfx::ToEnclosingRect(MathUtil::ProjectClippedRect(
  76                 clip_to_target, clip_node->data.combined_clip));
  77         clip_rect_in_target_space = gfx::ToEnclosingRect(
  78             MathUtil::ProjectClippedRect(clip_to_target, clip_node->data.clip));
  79       } else {
  80         // Computing a transform to an ancestor should always succeed.
  81         DCHECK(success);
  82         combined_clip_rect_in_target_space =
  83             gfx::ToEnclosingRect(MathUtil::MapClippedRect(
  84                 clip_to_target, clip_node->data.combined_clip));
  85         clip_rect_in_target_space = gfx::ToEnclosingRect(
  86             MathUtil::MapClippedRect(clip_to_target, clip_node->data.clip));
  87       }
  88
  89       if (clip_node->data.requires_tight_clip_rect)
  90         layer->set_clip_rect_in_target_space_from_property_trees(
  91             combined_clip_rect_in_target_space);
  92       else
  93         layer->set_clip_rect_in_target_space_from_property_trees(
  94             clip_rect_in_target_space);
  95
  96       gfx::Rect layer_content_rect = gfx::Rect(layer_bounds);
  97       gfx::Rect layer_content_bounds_in_target_space =
  98           MathUtil::MapEnclosingClippedRect(content_to_target,
  99                                             layer_content_rect);
 100       combined_clip_rect_in_target_space.Intersect(
 101           layer_content_bounds_in_target_space);
 102       clip_rect_in_target_space.Intersect(layer_content_bounds_in_target_space);
 103       if (combined_clip_rect_in_target_space.IsEmpty()) {
 104         layer->set_visible_rect_from_property_trees(gfx::Rect());
 105         continue;
 106       }
 107
 108       // If the layer is fully contained within the clip, treat it as fully
 109       // visible. Since clip_rect_in_target_space has already been intersected
 110       // with layer_content_bounds_in_target_space, the layer is fully contained
 111       // within the clip iff these rects are equal.
 112       if (combined_clip_rect_in_target_space ==
 113           layer_content_bounds_in_target_space) {
 114         layer->set_visible_rect_from_property_trees(gfx::Rect(layer_bounds));
 115         continue;
 116       }
 117
 118       gfx::Transform target_to_content;
 119       gfx::Transform target_to_layer;
 120
 121       if (transform_node->data.ancestors_are_invertible) {
 122         target_to_layer = transform_node->data.from_target;
 123         success = true;
 124       } else {
 125         success = transform_tree.ComputeTransformWithSourceSublayerScale(
 126             target_node->id, transform_node->id, &target_to_layer);
 127       }
 128
 129       if (!success) {
 130         // An animated singular transform may become non-singular during the
 131         // animation, so we still need to compute a visible rect. In this
 132         // situation, we treat the entire layer as visible.
 133         layer->set_visible_rect_from_property_trees(gfx::Rect(layer_bounds));
 134         continue;
 135       }
 136
 137       target_to_content.Translate(-layer->offset_to_transform_parent().x(),
 138                                   -layer->offset_to_transform_parent().y());
 139       target_to_content.PreconcatTransform(target_to_layer);
 140
 141       gfx::Rect visible_rect = MathUtil::ProjectEnclosingClippedRect(
 142           target_to_content, combined_clip_rect_in_target_space);
 143
 144       visible_rect.Intersect(gfx::Rect(layer_bounds));
 145
 146       layer->set_visible_rect_from_property_trees(visible_rect);
 147     } else {
 148       layer->set_visible_rect_from_property_trees(gfx::Rect(layer_bounds));
 149       layer->set_clip_rect_in_target_space_from_property_trees(
 150           gfx::Rect(layer_bounds));
 151     }
 152   }
 153 }
 154
 155 template <typename LayerType>
 156 static bool IsRootLayerOfNewRenderingContext(LayerType* layer) {
 157   if (layer->parent())
 158     return !layer->parent()->Is3dSorted() && layer->Is3dSorted();
 159   return layer->Is3dSorted();
 160 }
 161
 162 template <typename LayerType>
 163 static inline bool LayerIsInExisting3DRenderingContext(LayerType* layer) {
 164   return layer->Is3dSorted() && layer->parent() &&
 165          layer->parent()->Is3dSorted() &&
 166          layer->parent()->sorting_context_id() == layer->sorting_context_id();
 167 }
 168
 169 template <typename LayerType>
 170 static bool TransformToScreenIsKnown(LayerType* layer,
 171                                      const TransformTree& tree) {
 172   const TransformNode* node = tree.Node(layer->transform_tree_index());
 173   return !node->data.to_screen_is_animated;
 174 }
 175
 176 template <typename LayerType>
 177 static bool HasSingularTransform(LayerType* layer, const TransformTree& tree) {
 178   const TransformNode* node = tree.Node(layer->transform_tree_index());
 179   return !node->data.is_invertible || !node->data.ancestors_are_invertible;
 180 }
 181
 182 template <typename LayerType>
 183 static bool IsLayerBackFaceVisible(LayerType* layer,
 184                                    const TransformTree& tree) {
 185   // The current W3C spec on CSS transforms says that backface visibility should
 186   // be determined differently depending on whether the layer is in a "3d
 187   // rendering context" or not. For Chromium code, we can determine whether we
 188   // are in a 3d rendering context by checking if the parent preserves 3d.
 189
 190   if (LayerIsInExisting3DRenderingContext(layer))
 191     return DrawTransformFromPropertyTrees(layer, tree).IsBackFaceVisible();
 192
 193   // In this case, either the layer establishes a new 3d rendering context, or
 194   // is not in a 3d rendering context at all.
 195   return layer->transform().IsBackFaceVisible();
 196 }
 197
 198 template <typename LayerType>
 199 static bool IsSurfaceBackFaceVisible(LayerType* layer,
 200                                      const TransformTree& tree) {
 201   if (LayerIsInExisting3DRenderingContext(layer)) {
 202     const TransformNode* node = tree.Node(layer->transform_tree_index());
 203     // Draw transform as a contributing render surface.
 204     // TODO(enne): we shouldn't walk the tree during a tree walk.
 205     gfx::Transform surface_draw_transform;
 206     tree.ComputeTransform(node->id, node->data.target_id,
 207                           &surface_draw_transform);
 208     return surface_draw_transform.IsBackFaceVisible();
 209   }
 210
 211   if (IsRootLayerOfNewRenderingContext(layer))
 212     return layer->transform().IsBackFaceVisible();
 213
 214   // If the render_surface is not part of a new or existing rendering context,
 215   // then the layers that contribute to this surface will decide back-face
 216   // visibility for themselves.
 217   return false;
 218 }
 219
 220 template <typename LayerType>
 221 static bool IsAnimatingTransformToScreen(LayerType* layer,
 222                                          const TransformTree& tree) {
 223   const TransformNode* node = tree.Node(layer->transform_tree_index());
 224   return node->data.to_screen_is_animated;
 225 }
 226
 227 static inline bool TransformToScreenIsKnown(Layer* layer,
 228                                             const TransformTree& tree) {
 229   return !IsAnimatingTransformToScreen(layer, tree);
 230 }
 231
 232 static inline bool TransformToScreenIsKnown(LayerImpl* layer,
 233                                             const TransformTree& tree) {
 234   return true;
 235 }
 236
 237 template <typename LayerType>
 238 static bool HasInvertibleOrAnimatedTransform(LayerType* layer) {
 239   return layer->transform_is_invertible() ||
 240          layer->HasPotentiallyRunningTransformAnimation();
 241 }
 242
 243 static inline bool SubtreeShouldBeSkipped(LayerImpl* layer,
 244                                           bool layer_is_drawn,
 245                                           const TransformTree& tree) {
 246   // If the layer transform is not invertible, it should not be drawn.
 247   // TODO(ajuma): Correctly process subtrees with singular transform for the
 248   // case where we may animate to a non-singular transform and wish to
 249   // pre-raster.
 250   if (!HasInvertibleOrAnimatedTransform(layer))
 251     return true;
 252
 253   // When we need to do a readback/copy of a layer's output, we can not skip
 254   // it or any of its ancestors.
 255   if (layer->draw_properties().layer_or_descendant_has_copy_request)
 256     return false;
 257
 258   // If the layer is not drawn, then skip it and its subtree.
 259   if (!layer_is_drawn)
 260     return true;
 261
 262   if (layer->render_surface() && !layer->double_sided() &&
 263       IsSurfaceBackFaceVisible(layer, tree))
 264     return true;
 265
 266   // If layer is on the pending tree and opacity is being animated then
 267   // this subtree can't be skipped as we need to create, prioritize and
 268   // include tiles for this layer when deciding if tree can be activated.
 269   if (layer->layer_tree_impl()->IsPendingTree() &&
 270       layer->HasPotentiallyRunningOpacityAnimation())
 271     return false;
 272
 273   // The opacity of a layer always applies to its children (either implicitly
 274   // via a render surface or explicitly if the parent preserves 3D), so the
 275   // entire subtree can be skipped if this layer is fully transparent.
 276   return !layer->opacity();
 277 }
 278
 279 static inline bool SubtreeShouldBeSkipped(Layer* layer,
 280                                           bool layer_is_drawn,
 281                                           const TransformTree& tree) {
 282   // If the layer transform is not invertible, it should not be drawn.
 283   if (!layer->transform_is_invertible() &&
 284       !layer->HasPotentiallyRunningTransformAnimation())
 285     return true;
 286
 287   // When we need to do a readback/copy of a layer's output, we can not skip
 288   // it or any of its ancestors.
 289   if (layer->draw_properties().layer_or_descendant_has_copy_request)
 290     return false;
 291
 292   // If the layer is not drawn, then skip it and its subtree.
 293   if (!layer_is_drawn)
 294     return true;
 295
 296   if (layer->render_surface() && !layer->double_sided() &&
 297       !layer->HasPotentiallyRunningTransformAnimation() &&
 298       IsSurfaceBackFaceVisible(layer, tree))
 299     return true;
 300
 301   // If the opacity is being animated then the opacity on the main thread is
 302   // unreliable (since the impl thread may be using a different opacity), so it
 303   // should not be trusted.
 304   // In particular, it should not cause the subtree to be skipped.
 305   // Similarly, for layers that might animate opacity using an impl-only
 306   // animation, their subtree should also not be skipped.
 307   return !layer->opacity() && !layer->HasPotentiallyRunningOpacityAnimation() &&
 308          !layer->OpacityCanAnimateOnImplThread();
 309 }
 310
 311 template <typename LayerType>
 312 static bool LayerShouldBeSkipped(LayerType* layer,
 313                                  bool layer_is_drawn,
 314                                  const TransformTree& tree) {
 315   // Layers can be skipped if any of these conditions are met.
 316   //   - is not drawn due to it or one of its ancestors being hidden (or having
 317   //     no copy requests).
 318   //   - does not draw content.
 319   //   - is transparent.
 320   //   - has empty bounds
 321   //   - the layer is not double-sided, but its back face is visible.
 322   //
 323   // Some additional conditions need to be computed at a later point after the
 324   // recursion is finished.
 325   //   - the intersection of render_surface content and layer clip_rect is empty
 326   //   - the visible_layer_rect is empty
 327   //
 328   // Note, if the layer should not have been drawn due to being fully
 329   // transparent, we would have skipped the entire subtree and never made it
 330   // into this function, so it is safe to omit this check here.
 331   if (!layer_is_drawn)
 332     return true;
 333
 334   if (!layer->DrawsContent() || layer->bounds().IsEmpty())
 335     return true;
 336
 337   LayerType* backface_test_layer = layer;
 338   if (layer->use_parent_backface_visibility()) {
 339     DCHECK(layer->parent());
 340     DCHECK(!layer->parent()->use_parent_backface_visibility());
 341     backface_test_layer = layer->parent();
 342   }
 343
 344   // The layer should not be drawn if (1) it is not double-sided and (2) the
 345   // back of the layer is known to be facing the screen.
 346   if (!backface_test_layer->double_sided() &&
 347       TransformToScreenIsKnown(backface_test_layer, tree) &&
 348       IsLayerBackFaceVisible(backface_test_layer, tree))
 349     return true;
 350
 351   return false;
 352 }
 353
 354 template <typename LayerType>
 355 void FindLayersThatNeedUpdates(
 356     LayerType* layer,
 357     const TransformTree& tree,
 358     bool subtree_is_visible_from_ancestor,
 359     typename LayerType::LayerListType* update_layer_list,
 360     std::vector<LayerType*>* visible_layer_list) {
 361   bool layer_is_drawn =
 362       layer->HasCopyRequest() ||
 363       (subtree_is_visible_from_ancestor && !layer->hide_layer_and_subtree());
 364
 365   if (layer->parent() && SubtreeShouldBeSkipped(layer, layer_is_drawn, tree))
 366     return;
 367
 368   if (!LayerShouldBeSkipped(layer, layer_is_drawn, tree)) {
 369     visible_layer_list->push_back(layer);
 370     update_layer_list->push_back(layer);
 371   }
 372
 373   // Append mask layers to the update layer list.  They don't have valid visible
 374   // rects, so need to get added after the above calculation.  Replica layers
 375   // don't need to be updated.
 376   if (LayerType* mask_layer = layer->mask_layer())
 377     update_layer_list->push_back(mask_layer);
 378   if (LayerType* replica_layer = layer->replica_layer()) {
 379     if (LayerType* mask_layer = replica_layer->mask_layer())
 380       update_layer_list->push_back(mask_layer);
 381   }
 382
 383   for (size_t i = 0; i < layer->children().size(); ++i) {
 384     FindLayersThatNeedUpdates(layer->child_at(i), tree, layer_is_drawn,
 385                               update_layer_list, visible_layer_list);
 386   }
 387 }
 388
 389 }  // namespace
 390
 391 void ComputeClips(ClipTree* clip_tree, const TransformTree& transform_tree) {
 392   if (!clip_tree->needs_update())
 393     return;
 394   for (int i = 0; i < static_cast<int>(clip_tree->size()); ++i) {
 395     ClipNode* clip_node = clip_tree->Node(i);
 396     const TransformNode* transform_node =
 397         transform_tree.Node(clip_node->data.transform_id);
 398
 399     // Only descendants of a real clipping layer (i.e., not 0) may have their
 400     // clip adjusted due to intersecting with an ancestor clip.
 401     const bool is_clipped = clip_node->parent_id > 0;
 402     if (!is_clipped) {
 403       DCHECK(!clip_node->data.inherit_parent_target_space_clip);
 404       clip_node->data.combined_clip = clip_node->data.clip;
 405       if (clip_node->id > 0) {
 406         gfx::Transform to_target = transform_node->data.to_target;
 407         clip_node->data.clip_in_target_space =
 408             MathUtil::MapClippedRect(to_target, clip_node->data.combined_clip);
 409       }
 410       continue;
 411     }
 412
 413     ClipNode* parent_clip_node = clip_tree->parent(clip_node);
 414     const TransformNode* parent_transform_node =
 415         transform_tree.Node(parent_clip_node->data.transform_id);
 416
 417     // Clips must be combined in target space. We cannot, for example, combine
 418     // clips in the space of the child clip. The reason is non-affine
 419     // transforms. Say we have the following tree T->A->B->C, and B clips C, but
 420     // draw into target T. It may be the case that A applies a perspective
 421     // transform, and B and C are at different z positions. When projected into
 422     // target space, the relative sizes and positions of B and C can shift.
 423     // Since it's the relationship in target space that matters, that's where we
 424     // must combine clips.
 425     gfx::Transform parent_to_target;
 426     gfx::Transform clip_to_target;
 427
 428     gfx::Transform target_to_clip;
 429     gfx::Transform parent_to_transform_target;
 430     gfx::Transform transform_target_to_target;
 431
 432     const bool target_is_root_surface = clip_node->data.target_id == 1;
 433     // When the target is the root surface, we need to include the root
 434     // transform by walking up to the root of the transform tree.
 435     const int target_id =
 436         target_is_root_surface ? 0 : clip_node->data.target_id;
 437
 438     bool success = true;
 439     // When render surface applies clip, we need the clip from the target's
 440     // target space. But, as the combined clip is in parent clip's target
 441     // space, we need to first transform it from parent's target space to
 442     // target's target space.
 443     if (clip_node->data.inherit_parent_target_space_clip) {
 444       success &= transform_tree.ComputeTransformWithDestinationSublayerScale(
 445           parent_transform_node->id, transform_node->data.target_id,
 446           &parent_to_transform_target);
 447       success &= transform_tree.ComputeTransformWithSourceSublayerScale(
 448           transform_node->data.target_id, target_id,
 449           &transform_target_to_target);
 450       transform_target_to_target.matrix().postScale(
 451           transform_node->data.sublayer_scale.x(),
 452           transform_node->data.sublayer_scale.y(), 1.0);
 453     } else if (parent_transform_node->data.content_target_id ==
 454                clip_node->data.target_id) {
 455       parent_to_target = parent_transform_node->data.to_target;
 456     } else {
 457       success &= transform_tree.ComputeTransformWithDestinationSublayerScale(
 458           parent_transform_node->id, target_id, &parent_to_target);
 459     }
 460
 461     if (transform_node->data.content_target_id == clip_node->data.target_id) {
 462       clip_to_target = transform_node->data.to_target;
 463     } else {
 464       success &= transform_tree.ComputeTransformWithDestinationSublayerScale(
 465           transform_node->id, target_id, &clip_to_target);
 466     }
 467
 468     if (transform_node->data.content_target_id == clip_node->data.target_id &&
 469         transform_node->data.ancestors_are_invertible) {
 470       target_to_clip = transform_node->data.from_target;
 471     } else {
 472       success &= clip_to_target.GetInverse(&target_to_clip);
 473     }
 474
 475     // If we can't compute a transform, it's because we had to use the inverse
 476     // of a singular transform. We won't draw in this case, so there's no need
 477     // to compute clips.
 478     if (!success) {
 479       continue;
 480     }
 481
 482     // In order to intersect with as small a rect as possible, we do a
 483     // preliminary clip in target space so that when we project back, there's
 484     // less likelihood of intersecting the view plane.
 485     gfx::RectF inherited_clip_in_target_space;
 486     if (clip_node->data.inherit_parent_target_space_clip) {
 487       gfx::RectF combined_clip_in_transform_target_space;
 488       if (parent_transform_node->id > transform_node->data.target_id)
 489         combined_clip_in_transform_target_space = MathUtil::MapClippedRect(
 490             parent_to_transform_target, parent_clip_node->data.combined_clip);
 491       else
 492         combined_clip_in_transform_target_space = MathUtil::ProjectClippedRect(
 493             parent_to_transform_target, parent_clip_node->data.combined_clip);
 494       inherited_clip_in_target_space = MathUtil::ProjectClippedRect(
 495           transform_target_to_target, combined_clip_in_transform_target_space);
 496     } else if (parent_transform_node->id > target_id) {
 497       inherited_clip_in_target_space = MathUtil::MapClippedRect(
 498           parent_to_target, parent_clip_node->data.combined_clip);
 499     } else {
 500       inherited_clip_in_target_space = MathUtil::ProjectClippedRect(
 501           parent_to_target, parent_clip_node->data.combined_clip);
 502     }
 503
 504     // When render surface inherits its parent target space clip, the layer
 505     // that created the clip node doesn't apply any clip. So, we shouldn't clip
 506     // using the clip value stored in the clip node.
 507     gfx::RectF intersected_in_target_space;
 508     if (!clip_node->data.inherit_parent_target_space_clip) {
 509       gfx::RectF clip_in_target_space =
 510           MathUtil::MapClippedRect(clip_to_target, clip_node->data.clip);
 511
 512       intersected_in_target_space = gfx::IntersectRects(
 513           inherited_clip_in_target_space, clip_in_target_space);
 514     } else {
 515       intersected_in_target_space = inherited_clip_in_target_space;
 516     }
 517     clip_node->data.clip_in_target_space = intersected_in_target_space;
 518
 519     clip_node->data.combined_clip = MathUtil::ProjectClippedRect(
 520         target_to_clip, intersected_in_target_space);
 521
 522     if (!clip_node->data.inherit_parent_target_space_clip)
 523       clip_node->data.combined_clip.Intersect(clip_node->data.clip);
 524   }
 525   clip_tree->set_needs_update(false);
 526 }
 527
 528 void ComputeTransforms(TransformTree* transform_tree) {
 529   if (!transform_tree->needs_update())
 530     return;
 531   for (int i = 1; i < static_cast<int>(transform_tree->size()); ++i)
 532     transform_tree->UpdateTransforms(i);
 533   transform_tree->set_needs_update(false);
 534 }
 535
 536 void ComputeOpacities(EffectTree* effect_tree) {
 537   if (!effect_tree->needs_update())
 538     return;
 539   for (int i = 1; i < static_cast<int>(effect_tree->size()); ++i)
 540     effect_tree->UpdateOpacities(i);
 541   effect_tree->set_needs_update(false);
 542 }
 543
 544 template <typename LayerType>
 545 void ComputeVisibleRectsUsingPropertyTreesInternal(
 546     LayerType* root_layer,
 547     PropertyTrees* property_trees,
 548     typename LayerType::LayerListType* update_layer_list) {
 549   if (property_trees->transform_tree.needs_update())
 550     property_trees->clip_tree.set_needs_update(true);
 551   ComputeTransforms(&property_trees->transform_tree);
 552   ComputeClips(&property_trees->clip_tree, property_trees->transform_tree);
 553   ComputeOpacities(&property_trees->effect_tree);
 554
 555   const bool subtree_is_visible_from_ancestor = true;
 556   std::vector<LayerType*> visible_layer_list;
 557   FindLayersThatNeedUpdates(root_layer, property_trees->transform_tree,
 558                             subtree_is_visible_from_ancestor, update_layer_list,
 559                             &visible_layer_list);
 560   CalculateVisibleRects<LayerType>(visible_layer_list,
 561                                    property_trees->clip_tree,
 562                                    property_trees->transform_tree);
 563 }
 564
 565 void BuildPropertyTreesAndComputeVisibleRects(
 566     Layer* root_layer,
 567     const Layer* page_scale_layer,
 568     const Layer* inner_viewport_scroll_layer,
 569     const Layer* outer_viewport_scroll_layer,
 570     float page_scale_factor,
 571     float device_scale_factor,
 572     const gfx::Rect& viewport,
 573     const gfx::Transform& device_transform,
 574     PropertyTrees* property_trees,
 575     LayerList* update_layer_list) {
 576   PropertyTreeBuilder::BuildPropertyTrees(
 577       root_layer, page_scale_layer, inner_viewport_scroll_layer,
 578       outer_viewport_scroll_layer, page_scale_factor, device_scale_factor,
 579       viewport, device_transform, property_trees);
 580   ComputeVisibleRectsUsingPropertyTrees(root_layer, property_trees,
 581                                         update_layer_list);
 582 }
 583
 584 void BuildPropertyTreesAndComputeVisibleRects(
 585     LayerImpl* root_layer,
 586     const LayerImpl* page_scale_layer,
 587     const LayerImpl* inner_viewport_scroll_layer,
 588     const LayerImpl* outer_viewport_scroll_layer,
 589     float page_scale_factor,
 590     float device_scale_factor,
 591     const gfx::Rect& viewport,
 592     const gfx::Transform& device_transform,
 593     PropertyTrees* property_trees,
 594     LayerImplList* update_layer_list) {
 595   PropertyTreeBuilder::BuildPropertyTrees(
 596       root_layer, page_scale_layer, inner_viewport_scroll_layer,
 597       outer_viewport_scroll_layer, page_scale_factor, device_scale_factor,
 598       viewport, device_transform, property_trees);
 599   ComputeVisibleRectsUsingPropertyTrees(root_layer, property_trees,
 600                                         update_layer_list);
 601 }
 602
 603 void ComputeVisibleRectsUsingPropertyTrees(Layer* root_layer,
 604                                            PropertyTrees* property_trees,
 605                                            LayerList* update_layer_list) {
 606   ComputeVisibleRectsUsingPropertyTreesInternal(root_layer, property_trees,
 607                                                 update_layer_list);
 608 }
 609
 610 void ComputeVisibleRectsUsingPropertyTrees(LayerImpl* root_layer,
 611                                            PropertyTrees* property_trees,
 612                                            LayerImplList* update_layer_list) {
 613   ComputeVisibleRectsUsingPropertyTreesInternal(root_layer, property_trees,
 614                                                 update_layer_list);
 615 }
 616
 617 template <typename LayerType>
 618 gfx::Transform DrawTransformFromPropertyTreesInternal(
 619     const LayerType* layer,
 620     const TransformTree& tree) {
 621   const TransformNode* node = tree.Node(layer->transform_tree_index());
 622
 623   gfx::Transform xform;
 624   const bool owns_non_root_surface = layer->parent() && layer->render_surface();
 625   if (!owns_non_root_surface) {
 626     // If you're not the root, or you don't own a surface, you need to apply
 627     // your local offset.
 628     xform = node->data.to_target;
 629     if (layer->should_flatten_transform_from_property_tree())
 630       xform.FlattenTo2d();
 631     xform.Translate(layer->offset_to_transform_parent().x(),
 632                     layer->offset_to_transform_parent().y());
 633   } else {
 634     // Surfaces need to apply their sublayer scale.
 635     xform.Scale(node->data.sublayer_scale.x(), node->data.sublayer_scale.y());
 636   }
 637   return xform;
 638 }
 639
 640 gfx::Transform DrawTransformFromPropertyTrees(const Layer* layer,
 641                                               const TransformTree& tree) {
 642   return DrawTransformFromPropertyTreesInternal(layer, tree);
 643 }
 644
 645 gfx::Transform DrawTransformFromPropertyTrees(const LayerImpl* layer,
 646                                               const TransformTree& tree) {
 647   return DrawTransformFromPropertyTreesInternal(layer, tree);
 648 }
 649
 650 gfx::Transform DrawTransformOfRenderSurfaceFromPropertyTrees(
 651     const RenderSurfaceImpl* render_surface,
 652     const TransformTree& tree) {
 653   const TransformNode* node = tree.Node(render_surface->TransformTreeIndex());
 654   gfx::Transform render_surface_transform;
 655   // The draw transform of root render surface is identity tranform.
 656   if (node->id == 1)
 657     return render_surface_transform;
 658   const TransformNode* target_node = tree.Node(node->data.target_id);
 659   if (target_node->id == 1)
 660     target_node = tree.Node(0);
 661   tree.ComputeTransformWithDestinationSublayerScale(node->id, target_node->id,
 662                                                     &render_surface_transform);
 663   if (node->data.sublayer_scale.x() != 0.0 &&
 664       node->data.sublayer_scale.y() != 0.0)
 665     render_surface_transform.Scale(1.0 / node->data.sublayer_scale.x(),
 666                                    1.0 / node->data.sublayer_scale.y());
 667   return render_surface_transform;
 668 }
 669
 670 bool RenderSurfaceIsClippedFromPropertyTrees(
 671     const RenderSurfaceImpl* render_surface,
 672     const ClipTree& tree) {
 673   const ClipNode* node = tree.Node(render_surface->ClipTreeIndex());
 674   // If the render surface's owning layer doesn't form a clip node, it is not
 675   // clipped.
 676   if (render_surface->OwningLayerId() != node->owner_id)
 677     return false;
 678   return node->data.render_surface_is_clipped;
 679 }
 680
 681 gfx::Rect ClipRectOfRenderSurfaceFromPropertyTrees(
 682     const RenderSurfaceImpl* render_surface,
 683     const ClipTree& clip_tree) {
 684   if (!RenderSurfaceIsClippedFromPropertyTrees(render_surface, clip_tree))
 685     return gfx::Rect();
 686   const ClipNode* clip_node = clip_tree.Node(render_surface->ClipTreeIndex());
 687   const ClipNode* parent_clip_node = clip_tree.parent(clip_node);
 688   return gfx::ToEnclosingRect(parent_clip_node->data.clip_in_target_space);
 689 }
 690
 691 gfx::Transform ScreenSpaceTransformOfRenderSurfaceFromPropertyTrees(
 692     RenderSurfaceImpl* render_surface,
 693     const TransformTree& tree) {
 694   const TransformNode* node = tree.Node(render_surface->TransformTreeIndex());
 695   gfx::Transform screen_space_transform;
 696   // The screen space transform of root render surface is identity tranform.
 697   if (node->id == 1)
 698     return screen_space_transform;
 699   screen_space_transform = node->data.to_screen;
 700   if (node->data.sublayer_scale.x() != 0.0 &&
 701       node->data.sublayer_scale.y() != 0.0)
 702     screen_space_transform.Scale(1.0 / node->data.sublayer_scale.x(),
 703                                  1.0 / node->data.sublayer_scale.y());
 704   return screen_space_transform;
 705 }
 706
 707 template <typename LayerType>
 708 gfx::Transform ScreenSpaceTransformFromPropertyTreesInternal(
 709     LayerType* layer,
 710     const TransformTree& tree) {
 711   gfx::Transform xform(1, 0, 0, 1, layer->offset_to_transform_parent().x(),
 712                        layer->offset_to_transform_parent().y());
 713   if (layer->transform_tree_index() >= 0) {
 714     gfx::Transform ssxform =
 715         tree.Node(layer->transform_tree_index())->data.to_screen;
 716     xform.ConcatTransform(ssxform);
 717     if (layer->should_flatten_transform_from_property_tree())
 718       xform.FlattenTo2d();
 719   }
 720   return xform;
 721 }
 722
 723 gfx::Transform ScreenSpaceTransformFromPropertyTrees(
 724     const Layer* layer,
 725     const TransformTree& tree) {
 726   return ScreenSpaceTransformFromPropertyTreesInternal(layer, tree);
 727 }
 728
 729 gfx::Transform ScreenSpaceTransformFromPropertyTrees(
 730     const LayerImpl* layer,
 731     const TransformTree& tree) {
 732   return ScreenSpaceTransformFromPropertyTreesInternal(layer, tree);
 733 }
 734
 735 template <typename LayerType>
 736 bool ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(
 737     LayerType* layer,
 738     const TransformTree& tree) {
 739   return tree.Node(layer->transform_tree_index())->data.to_screen_is_animated;
 740 }
 741
 742 bool ScreenSpaceTransformIsAnimatingFromPropertyTrees(
 743     const Layer* layer,
 744     const TransformTree& tree) {
 745   return ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(layer, tree);
 746 }
 747
 748 bool ScreenSpaceTransformIsAnimatingFromPropertyTrees(
 749     const LayerImpl* layer,
 750     const TransformTree& tree) {
 751   return ScreenSpaceTransformIsAnimatingFromPropertyTreesInternal(layer, tree);
 752 }
 753
 754 template <typename LayerType>
 755 float DrawOpacityFromPropertyTreesInternal(LayerType layer,
 756                                            const EffectTree& tree) {
 757   if (!layer->render_target())
 758     return 0.f;
 759
 760   const EffectNode* target_node =
 761       tree.Node(layer->render_target()->effect_tree_index());
 762   const EffectNode* node = tree.Node(layer->effect_tree_index());
 763   if (node == target_node)
 764     return 1.f;
 765
 766   float draw_opacity = 1.f;
 767   while (node != target_node) {
 768     draw_opacity *= node->data.opacity;
 769     node = tree.parent(node);
 770   }
 771   return draw_opacity;
 772 }
 773
 774 float DrawOpacityFromPropertyTrees(const Layer* layer, const EffectTree& tree) {
 775   return DrawOpacityFromPropertyTreesInternal(layer, tree);
 776 }
 777
 778 float DrawOpacityFromPropertyTrees(const LayerImpl* layer,
 779                                    const EffectTree& tree) {
 780   return DrawOpacityFromPropertyTreesInternal(layer, tree);
 781 }
 782
 783 float DrawOpacityOfRenderSurfaceFromPropertyTrees(
 784     RenderSurfaceImpl* render_surface,
 785     const EffectTree& tree) {
 786   const EffectNode* node = tree.Node(render_surface->EffectTreeIndex());
 787   float target_opacity_tree_index = render_surface->TargetEffectTreeIndex();
 788   if (target_opacity_tree_index < 0)
 789     return node->data.screen_space_opacity;
 790   const EffectNode* target_node = tree.Node(target_opacity_tree_index);
 791   float draw_opacity = 1.f;
 792   while (node != target_node) {
 793     draw_opacity *= node->data.opacity;
 794     node = tree.parent(node);
 795   }
 796   return draw_opacity;
 797 }
 798
 799 bool CanUseLcdTextFromPropertyTrees(const LayerImpl* layer,
 800                                     bool layers_always_allowed_lcd_text,
 801                                     bool can_use_lcd_text,
 802                                     PropertyTrees* property_trees) {
 803   if (layers_always_allowed_lcd_text)
 804     return true;
 805   if (!can_use_lcd_text)
 806     return false;
 807   if (!layer->contents_opaque())
 808     return false;
 809   DCHECK(!property_trees->transform_tree.needs_update());
 810   DCHECK(!property_trees->effect_tree.needs_update());
 811
 812   const EffectNode* opacity_node =
 813       property_trees->effect_tree.Node(layer->effect_tree_index());
 814   if (opacity_node->data.screen_space_opacity != 1.f)
 815     return false;
 816   const TransformNode* transform_node =
 817       property_trees->transform_tree.Node(layer->transform_tree_index());
 818   if (!transform_node->data.node_and_ancestors_have_only_integer_translation)
 819     return false;
 820   if (static_cast<int>(layer->offset_to_transform_parent().x()) !=
 821       layer->offset_to_transform_parent().x())
 822     return false;
 823   if (static_cast<int>(layer->offset_to_transform_parent().y()) !=
 824       layer->offset_to_transform_parent().y())
 825     return false;
 826   return true;
 827 }
 828
 829 gfx::Rect DrawableContentRectOfSurfaceFromPropertyTrees(
 830     const RenderSurfaceImpl* render_surface,
 831     const TransformTree& transform_tree) {
 832   gfx::Rect drawable_content_rect =
 833       gfx::ToEnclosingRect(MathUtil::MapClippedRect(
 834           DrawTransformOfRenderSurfaceFromPropertyTrees(render_surface,
 835                                                         transform_tree),
 836           render_surface->content_rect_from_property_trees()));
 837   if (render_surface->HasReplica()) {
 838     drawable_content_rect.Union(gfx::ToEnclosingRect(MathUtil::MapClippedRect(
 839         render_surface->ReplicaDrawTransform(),
 840         render_surface->content_rect_from_property_trees())));
 841   }
 842   return drawable_content_rect;
 843 }
 844
 845 gfx::Rect DrawableContentRectFromPropertyTrees(
 846     const LayerImpl* layer,
 847     const TransformTree& transform_tree) {
 848   gfx::Rect drawable_content_rect = MathUtil::MapEnclosingClippedRect(
 849       DrawTransformFromPropertyTrees(layer, transform_tree),
 850       gfx::Rect(layer->bounds()));
 851   if (layer->is_clipped() && layer->clip_tree_index() > 0) {
 852     drawable_content_rect.Intersect(
 853         layer->clip_rect_in_target_space_from_property_trees());
 854   }
 855   return drawable_content_rect;
 856 }
 857
 858 gfx::Rect ClipRectFromPropertyTrees(const LayerImpl* layer,
 859                                     const TransformTree& transform_tree) {
 860   if (layer->is_clipped() && layer->clip_tree_index() > 0)
 861     return layer->clip_rect_in_target_space_from_property_trees();
 862   return MathUtil::MapEnclosingClippedRect(
 863       DrawTransformFromPropertyTrees(layer, transform_tree),
 864       gfx::Rect(layer->bounds()));
 865 }
 866
 867 gfx::Rect ViewportRectFromPropertyTrees(const ClipTree& tree) {
 868   return gfx::ToEnclosingRect(tree.Node(1)->data.clip);
 869 }
 870
 871 }  // namespace cc