root/ui/compositor/layer.cc

DEFINITIONS

1. GetRoot
2. device_scale_factor_
3. device_scale_factor_
4. UsingPictureLayer
5. GetCompositor
6. opacity
7. SetCompositor
8. Add
9. Remove
10. StackAtTop
11. StackAbove
12. StackAtBottom
13. StackBelow
14. Contains
15. SetAnimator
16. GetAnimator
17. SetTransform
18. GetTargetTransform
19. SetBounds
20. GetTargetBounds
21. SetMasksToBounds
22. GetMasksToBounds
23. SetOpacity
24. GetCombinedOpacity
25. SetBackgroundBlur
26. SetLayerSaturation
27. SetLayerBrightness
28. GetTargetBrightness
29. SetLayerGrayscale
30. GetTargetGrayscale
31. SetLayerInverted
32. SetMaskLayer
33. SetBackgroundZoom
34. SetLayerFilters
35. SetLayerBackgroundFilters
36. GetTargetOpacity
37. SetVisible
38. GetTargetVisibility
39. IsDrawn
40. ShouldDraw
41. ConvertPointToLayer
42. GetTargetTransformRelativeTo
43. ConvertTransformToCCTransform
44. SetFillsBoundsOpaquely
45. SetFillsBoundsCompletely
46. SwitchToLayer
47. SwitchCCLayerForTest
48. SetExternalTexture
49. SetTextureMailbox
50. GetTextureMailbox
51. SetShowDelegatedContent
52. SetShowPaintedContent
53. SetColor
54. SchedulePaint
55. ScheduleDraw
56. SendDamagedRects
57. SuppressPaint
58. OnDeviceScaleFactorChanged
59. RequestCopyOfOutput
60. PaintContents
61. FillsBoundsCompletely
62. PrepareTexture
63. PrepareTextureMailbox
64. SetForceRenderSurface
65. AppendAsTraceFormat
66. TakeDebugInfo
67. OnAnimationStarted
68. StackRelativeTo
69. ConvertPointForAncestor
70. ConvertPointFromAncestor
71. SetBoundsFromAnimation
72. SetTransformFromAnimation
73. SetOpacityFromAnimation
74. SetVisibilityFromAnimation
75. SetBrightnessFromAnimation
76. SetGrayscaleFromAnimation
77. SetColorFromAnimation
78. ScheduleDrawForAnimation
79. GetBoundsForAnimation
80. GetTransformForAnimation
81. GetOpacityForAnimation
82. GetVisibilityForAnimation
83. GetBrightnessForAnimation
84. GetGrayscaleForAnimation
85. GetColorForAnimation
86. GetDeviceScaleFactor
87. AddThreadedAnimation
88. RemoveThreadedAnimation
89. SendPendingThreadedAnimations
90. CreateWebLayer
91. RecomputeCCTransformFromTransform
92. transform
93. RecomputeDrawsContentAndUVRect
94. RecomputePosition

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/compositor/layer.h"

#include <algorithm>

#include "base/command_line.h"
#include "base/debug/trace_event.h"
#include "base/json/json_writer.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "cc/base/scoped_ptr_algorithm.h"
#include "cc/layers/content_layer.h"
#include "cc/layers/delegated_renderer_layer.h"
#include "cc/layers/picture_layer.h"
#include "cc/layers/solid_color_layer.h"
#include "cc/layers/texture_layer.h"
#include "cc/output/copy_output_request.h"
#include "cc/output/delegated_frame_data.h"
#include "cc/output/filter_operation.h"
#include "cc/output/filter_operations.h"
#include "cc/resources/transferable_resource.h"
#include "ui/compositor/compositor_switches.h"
#include "ui/compositor/dip_util.h"
#include "ui/compositor/layer_animator.h"
#include "ui/gfx/animation/animation.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/display.h"
#include "ui/gfx/interpolated_transform.h"
#include "ui/gfx/point3_f.h"
#include "ui/gfx/point_conversions.h"
#include "ui/gfx/size_conversions.h"

namespace {

const ui::Layer* GetRoot(const ui::Layer* layer) {
  while (layer->parent())
    layer = layer->parent();
  return layer;
}

struct UIImplSidePaintingStatus {
  UIImplSidePaintingStatus()
      : enabled(ui::IsUIImplSidePaintingEnabled()) {
  }
  bool enabled;
};
base::LazyInstance<UIImplSidePaintingStatus> g_ui_impl_side_painting_status =
    LAZY_INSTANCE_INITIALIZER;

}  // namespace

namespace ui {

Layer::Layer()
    : type_(LAYER_TEXTURED),
      compositor_(NULL),
      parent_(NULL),
      visible_(true),
      force_render_surface_(false),
      fills_bounds_opaquely_(true),
      fills_bounds_completely_(false),
      background_blur_radius_(0),
      layer_saturation_(0.0f),
      layer_brightness_(0.0f),
      layer_grayscale_(0.0f),
      layer_inverted_(false),
      layer_mask_(NULL),
      layer_mask_back_link_(NULL),
      zoom_(1),
      zoom_inset_(0),
      delegate_(NULL),
      owner_(NULL),
      cc_layer_(NULL),
      scale_content_(true),
      device_scale_factor_(1.0f) {
  CreateWebLayer();
}

Layer::Layer(LayerType type)
    : type_(type),
      compositor_(NULL),
      parent_(NULL),
      visible_(true),
      force_render_surface_(false),
      fills_bounds_opaquely_(true),
      fills_bounds_completely_(false),
      background_blur_radius_(0),
      layer_saturation_(0.0f),
      layer_brightness_(0.0f),
      layer_grayscale_(0.0f),
      layer_inverted_(false),
      layer_mask_(NULL),
      layer_mask_back_link_(NULL),
      zoom_(1),
      zoom_inset_(0),
      delegate_(NULL),
      owner_(NULL),
      cc_layer_(NULL),
      scale_content_(true),
      device_scale_factor_(1.0f) {
  CreateWebLayer();
}

Layer::~Layer() {
  // Destroying the animator may cause observers to use the layer (and
  // indirectly the WebLayer). Destroy the animator first so that the WebLayer
  // is still around.
  if (animator_.get())
    animator_->SetDelegate(NULL);
  animator_ = NULL;
  if (compositor_)
    compositor_->SetRootLayer(NULL);
  if (parent_)
    parent_->Remove(this);
  if (layer_mask_)
    SetMaskLayer(NULL);
  if (layer_mask_back_link_)
    layer_mask_back_link_->SetMaskLayer(NULL);
  for (size_t i = 0; i < children_.size(); ++i)
    children_[i]->parent_ = NULL;
  cc_layer_->RemoveLayerAnimationEventObserver(this);
  cc_layer_->RemoveFromParent();
}

// static
bool Layer::UsingPictureLayer() {
  return g_ui_impl_side_painting_status.Get().enabled;
}

Compositor* Layer::GetCompositor() {
  return GetRoot(this)->compositor_;
}

float Layer::opacity() const {
  return cc_layer_->opacity();
}

void Layer::SetCompositor(Compositor* compositor) {
  // This function must only be called to set the compositor on the root layer,
  // or to reset it.
  DCHECK(!compositor || !compositor_);
  DCHECK(!compositor || compositor->root_layer() == this);
  DCHECK(!parent_);
  compositor_ = compositor;
  if (compositor) {
    OnDeviceScaleFactorChanged(compositor->device_scale_factor());
    SendPendingThreadedAnimations();
  }
}

void Layer::Add(Layer* child) {
  DCHECK(!child->compositor_);
  if (child->parent_)
    child->parent_->Remove(child);
  child->parent_ = this;
  children_.push_back(child);
  cc_layer_->AddChild(child->cc_layer_);
  child->OnDeviceScaleFactorChanged(device_scale_factor_);
  if (GetCompositor())
    child->SendPendingThreadedAnimations();
}

void Layer::Remove(Layer* child) {
  std::vector<Layer*>::iterator i =
      std::find(children_.begin(), children_.end(), child);
  DCHECK(i != children_.end());
  children_.erase(i);
  child->parent_ = NULL;
  child->cc_layer_->RemoveFromParent();
}

void Layer::StackAtTop(Layer* child) {
  if (children_.size() <= 1 || child == children_.back())
    return;  // Already in front.
  StackAbove(child, children_.back());
}

void Layer::StackAbove(Layer* child, Layer* other) {
  StackRelativeTo(child, other, true);
}

void Layer::StackAtBottom(Layer* child) {
  if (children_.size() <= 1 || child == children_.front())
    return;  // Already on bottom.
  StackBelow(child, children_.front());
}

void Layer::StackBelow(Layer* child, Layer* other) {
  StackRelativeTo(child, other, false);
}

bool Layer::Contains(const Layer* other) const {
  for (const Layer* parent = other; parent; parent = parent->parent()) {
    if (parent == this)
      return true;
  }
  return false;
}

void Layer::SetAnimator(LayerAnimator* animator) {
  if (animator)
    animator->SetDelegate(this);
  animator_ = animator;
}

LayerAnimator* Layer::GetAnimator() {
  if (!animator_.get())
    SetAnimator(LayerAnimator::CreateDefaultAnimator());
  return animator_.get();
}

void Layer::SetTransform(const gfx::Transform& transform) {
  GetAnimator()->SetTransform(transform);
}

gfx::Transform Layer::GetTargetTransform() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::TRANSFORM)) {
    return animator_->GetTargetTransform();
  }
  return transform();
}

void Layer::SetBounds(const gfx::Rect& bounds) {
  GetAnimator()->SetBounds(bounds);
}

gfx::Rect Layer::GetTargetBounds() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::BOUNDS)) {
    return animator_->GetTargetBounds();
  }
  return bounds_;
}

void Layer::SetMasksToBounds(bool masks_to_bounds) {
  cc_layer_->SetMasksToBounds(masks_to_bounds);
}

bool Layer::GetMasksToBounds() const {
  return cc_layer_->masks_to_bounds();
}

void Layer::SetOpacity(float opacity) {
  GetAnimator()->SetOpacity(opacity);
}

float Layer::GetCombinedOpacity() const {
  float opacity = this->opacity();
  Layer* current = this->parent_;
  while (current) {
    opacity *= current->opacity();
    current = current->parent_;
  }
  return opacity;
}

void Layer::SetBackgroundBlur(int blur_radius) {
  background_blur_radius_ = blur_radius;

  SetLayerBackgroundFilters();
}

void Layer::SetLayerSaturation(float saturation) {
  layer_saturation_ = saturation;
  SetLayerFilters();
}

void Layer::SetLayerBrightness(float brightness) {
  GetAnimator()->SetBrightness(brightness);
}

float Layer::GetTargetBrightness() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::BRIGHTNESS)) {
    return animator_->GetTargetBrightness();
  }
  return layer_brightness();
}

void Layer::SetLayerGrayscale(float grayscale) {
  GetAnimator()->SetGrayscale(grayscale);
}

float Layer::GetTargetGrayscale() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::GRAYSCALE)) {
    return animator_->GetTargetGrayscale();
  }
  return layer_grayscale();
}

void Layer::SetLayerInverted(bool inverted) {
  layer_inverted_ = inverted;
  SetLayerFilters();
}

void Layer::SetMaskLayer(Layer* layer_mask) {
  // The provided mask should not have a layer mask itself.
  DCHECK(!layer_mask ||
         (!layer_mask->layer_mask_layer() &&
          layer_mask->children().empty() &&
          !layer_mask->layer_mask_back_link_));
  DCHECK(!layer_mask_back_link_);
  if (layer_mask_ == layer_mask)
    return;
  // We need to de-reference the currently linked object so that no problem
  // arises if the mask layer gets deleted before this object.
  if (layer_mask_)
    layer_mask_->layer_mask_back_link_ = NULL;
  layer_mask_ = layer_mask;
  cc_layer_->SetMaskLayer(
      layer_mask ? layer_mask->cc_layer() : NULL);
  // We need to reference the linked object so that it can properly break the
  // link to us when it gets deleted.
  if (layer_mask) {
    layer_mask->layer_mask_back_link_ = this;
    layer_mask->OnDeviceScaleFactorChanged(device_scale_factor_);
  }
}

void Layer::SetBackgroundZoom(float zoom, int inset) {
  zoom_ = zoom;
  zoom_inset_ = inset;

  SetLayerBackgroundFilters();
}

void Layer::SetLayerFilters() {
  cc::FilterOperations filters;
  if (layer_saturation_) {
    filters.Append(cc::FilterOperation::CreateSaturateFilter(
        layer_saturation_));
  }
  if (layer_grayscale_) {
    filters.Append(cc::FilterOperation::CreateGrayscaleFilter(
        layer_grayscale_));
  }
  if (layer_inverted_)
    filters.Append(cc::FilterOperation::CreateInvertFilter(1.0));
  // Brightness goes last, because the resulting colors neeed clamping, which
  // cause further color matrix filters to be applied separately. In this order,
  // they all can be combined in a single pass.
  if (layer_brightness_) {
    filters.Append(cc::FilterOperation::CreateSaturatingBrightnessFilter(
        layer_brightness_));
  }

  cc_layer_->SetFilters(filters);
}

void Layer::SetLayerBackgroundFilters() {
  cc::FilterOperations filters;
  if (zoom_ != 1)
    filters.Append(cc::FilterOperation::CreateZoomFilter(zoom_, zoom_inset_));

  if (background_blur_radius_) {
    filters.Append(cc::FilterOperation::CreateBlurFilter(
        background_blur_radius_));
  }

  cc_layer_->SetBackgroundFilters(filters);
}

float Layer::GetTargetOpacity() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::OPACITY))
    return animator_->GetTargetOpacity();
  return opacity();
}

void Layer::SetVisible(bool visible) {
  GetAnimator()->SetVisibility(visible);
}

bool Layer::GetTargetVisibility() const {
  if (animator_.get() && animator_->IsAnimatingProperty(
      LayerAnimationElement::VISIBILITY))
    return animator_->GetTargetVisibility();
  return visible_;
}

bool Layer::IsDrawn() const {
  const Layer* layer = this;
  while (layer && layer->visible_)
    layer = layer->parent_;
  return layer == NULL;
}

bool Layer::ShouldDraw() const {
  return type_ != LAYER_NOT_DRAWN && GetCombinedOpacity() > 0.0f;
}

// static
void Layer::ConvertPointToLayer(const Layer* source,
                                const Layer* target,
                                gfx::Point* point) {
  if (source == target)
    return;

  const Layer* root_layer = GetRoot(source);
  CHECK_EQ(root_layer, GetRoot(target));

  if (source != root_layer)
    source->ConvertPointForAncestor(root_layer, point);
  if (target != root_layer)
    target->ConvertPointFromAncestor(root_layer, point);
}

bool Layer::GetTargetTransformRelativeTo(const Layer* ancestor,
                                         gfx::Transform* transform) const {
  const Layer* p = this;
  for (; p && p != ancestor; p = p->parent()) {
    gfx::Transform translation;
    translation.Translate(static_cast<float>(p->bounds().x()),
                          static_cast<float>(p->bounds().y()));
    // Use target transform so that result will be correct once animation is
    // finished.
    if (!p->GetTargetTransform().IsIdentity())
      transform->ConcatTransform(p->GetTargetTransform());
    transform->ConcatTransform(translation);
  }
  return p == ancestor;
}

// static
gfx::Transform Layer::ConvertTransformToCCTransform(
    const gfx::Transform& transform,
    float device_scale_factor) {
  gfx::Transform cc_transform;
  cc_transform.Scale(device_scale_factor, device_scale_factor);
  cc_transform.PreconcatTransform(transform);
  cc_transform.Scale(1.0f / device_scale_factor, 1.0f / device_scale_factor);
  return cc_transform;
}

void Layer::SetFillsBoundsOpaquely(bool fills_bounds_opaquely) {
  if (fills_bounds_opaquely_ == fills_bounds_opaquely)
    return;

  fills_bounds_opaquely_ = fills_bounds_opaquely;

  cc_layer_->SetContentsOpaque(fills_bounds_opaquely);
}

void Layer::SetFillsBoundsCompletely(bool fills_bounds_completely) {
  fills_bounds_completely_ = fills_bounds_completely;
}

void Layer::SwitchToLayer(scoped_refptr<cc::Layer> new_layer) {
  // Finish animations being handled by cc_layer_.
  if (animator_.get()) {
    animator_->StopAnimatingProperty(LayerAnimationElement::TRANSFORM);
    animator_->StopAnimatingProperty(LayerAnimationElement::OPACITY);
  }

  if (texture_layer_.get())
    texture_layer_->ClearClient();
  // TODO(piman): delegated_renderer_layer_ cleanup.

  cc_layer_->RemoveAllChildren();
  if (parent_) {
    DCHECK(parent_->cc_layer_);
    parent_->cc_layer_->ReplaceChild(cc_layer_, new_layer);
  }
  cc_layer_->SetLayerClient(NULL);
  cc_layer_->RemoveLayerAnimationEventObserver(this);
  new_layer->SetOpacity(cc_layer_->opacity());
  new_layer->SetTransform(cc_layer_->transform());
  new_layer->SetPosition(cc_layer_->position());

  cc_layer_ = new_layer.get();
  content_layer_ = NULL;
  solid_color_layer_ = NULL;
  texture_layer_ = NULL;
  delegated_renderer_layer_ = NULL;

  cc_layer_->AddLayerAnimationEventObserver(this);
  for (size_t i = 0; i < children_.size(); ++i) {
    DCHECK(children_[i]->cc_layer_);
    cc_layer_->AddChild(children_[i]->cc_layer_);
  }
  cc_layer_->SetLayerClient(this);
  cc_layer_->SetAnchorPoint(gfx::PointF());
  cc_layer_->SetContentsOpaque(fills_bounds_opaquely_);
  cc_layer_->SetForceRenderSurface(force_render_surface_);
  cc_layer_->SetIsDrawable(type_ != LAYER_NOT_DRAWN);
  cc_layer_->SetHideLayerAndSubtree(!visible_);
}

void Layer::SwitchCCLayerForTest() {
  scoped_refptr<cc::Layer> new_layer;
  if (Layer::UsingPictureLayer())
    new_layer = cc::PictureLayer::Create(this);
  else
    new_layer = cc::ContentLayer::Create(this);
  SwitchToLayer(new_layer);
  content_layer_ = new_layer;
}

void Layer::SetExternalTexture(Texture* texture) {
  DCHECK(texture);

  // Hold a ref to the old |Texture| until we have updated all
  // compositor references to the texture id that it holds.
  scoped_refptr<ui::Texture> old_texture = texture_;

  DCHECK_EQ(type_, LAYER_TEXTURED);
  DCHECK(!solid_color_layer_.get());
  texture_ = texture;
  if (!texture_layer_.get()) {
    scoped_refptr<cc::TextureLayer> new_layer = cc::TextureLayer::Create(this);
    new_layer->SetFlipped(texture_->flipped());
    SwitchToLayer(new_layer);
    texture_layer_ = new_layer;
  }
  RecomputeDrawsContentAndUVRect();
}

void Layer::SetTextureMailbox(
    const cc::TextureMailbox& mailbox,
    scoped_ptr<cc::SingleReleaseCallback> release_callback,
    float scale_factor) {
  DCHECK_EQ(type_, LAYER_TEXTURED);
  DCHECK(!solid_color_layer_.get());
  texture_ = NULL;
  if (!texture_layer_.get() || !texture_layer_->uses_mailbox()) {
    scoped_refptr<cc::TextureLayer> new_layer =
        cc::TextureLayer::CreateForMailbox(this);
    new_layer->SetFlipped(false);
    SwitchToLayer(new_layer);
    texture_layer_ = new_layer;
  }
  texture_layer_->SetTextureMailbox(mailbox, release_callback.Pass());
  mailbox_ = mailbox;
  mailbox_scale_factor_ = scale_factor;
  RecomputeDrawsContentAndUVRect();
}

cc::TextureMailbox Layer::GetTextureMailbox(float* scale_factor) {
  if (scale_factor)
    *scale_factor = mailbox_scale_factor_;
  return mailbox_;
}

void Layer::SetShowDelegatedContent(cc::DelegatedFrameProvider* frame_provider,
                                    gfx::Size frame_size_in_dip) {
  DCHECK_EQ(type_, LAYER_TEXTURED);

  scoped_refptr<cc::DelegatedRendererLayer> new_layer =
      cc::DelegatedRendererLayer::Create(frame_provider);
  SwitchToLayer(new_layer);
  delegated_renderer_layer_ = new_layer;

  delegated_frame_size_in_dip_ = frame_size_in_dip;
  RecomputeDrawsContentAndUVRect();
}

void Layer::SetShowPaintedContent() {
  if (content_layer_.get())
    return;

  scoped_refptr<cc::Layer> new_layer;
  if (Layer::UsingPictureLayer())
    new_layer = cc::PictureLayer::Create(this);
  else
    new_layer = cc::ContentLayer::Create(this);
  SwitchToLayer(new_layer);
  content_layer_ = new_layer;

  mailbox_ = cc::TextureMailbox();
  texture_ = NULL;

  RecomputeDrawsContentAndUVRect();
}

void Layer::SetColor(SkColor color) { GetAnimator()->SetColor(color); }

bool Layer::SchedulePaint(const gfx::Rect& invalid_rect) {
  if (type_ == LAYER_SOLID_COLOR || (!delegate_ && !texture_.get()))
    return false;

  damaged_region_.op(invalid_rect.x(),
                     invalid_rect.y(),
                     invalid_rect.right(),
                     invalid_rect.bottom(),
                     SkRegion::kUnion_Op);
  ScheduleDraw();
  return true;
}

void Layer::ScheduleDraw() {
  Compositor* compositor = GetCompositor();
  if (compositor)
    compositor->ScheduleDraw();
}

void Layer::SendDamagedRects() {
  if ((delegate_ || texture_.get()) && !damaged_region_.isEmpty()) {
    for (SkRegion::Iterator iter(damaged_region_); !iter.done(); iter.next()) {
      const SkIRect& sk_damaged = iter.rect();
      gfx::Rect damaged(
          sk_damaged.x(),
          sk_damaged.y(),
          sk_damaged.width(),
          sk_damaged.height());

      gfx::Rect damaged_in_pixel = ConvertRectToPixel(this, damaged);
      cc_layer_->SetNeedsDisplayRect(damaged_in_pixel);
    }
    damaged_region_.setEmpty();
  }
  for (size_t i = 0; i < children_.size(); ++i)
    children_[i]->SendDamagedRects();
}

void Layer::SuppressPaint() {
  if (!delegate_)
    return;
  delegate_ = NULL;
  for (size_t i = 0; i < children_.size(); ++i)
    children_[i]->SuppressPaint();
}

void Layer::OnDeviceScaleFactorChanged(float device_scale_factor) {
  if (device_scale_factor_ == device_scale_factor)
    return;
  if (animator_.get())
    animator_->StopAnimatingProperty(LayerAnimationElement::TRANSFORM);
  gfx::Transform transform = this->transform();
  device_scale_factor_ = device_scale_factor;
  RecomputeCCTransformFromTransform(transform);
  RecomputeDrawsContentAndUVRect();
  RecomputePosition();
  SchedulePaint(gfx::Rect(bounds_.size()));
  if (delegate_)
    delegate_->OnDeviceScaleFactorChanged(device_scale_factor);
  for (size_t i = 0; i < children_.size(); ++i)
    children_[i]->OnDeviceScaleFactorChanged(device_scale_factor);
  if (layer_mask_)
    layer_mask_->OnDeviceScaleFactorChanged(device_scale_factor);
}

void Layer::RequestCopyOfOutput(scoped_ptr<cc::CopyOutputRequest> request) {
  cc_layer_->RequestCopyOfOutput(request.Pass());
}

void Layer::PaintContents(SkCanvas* sk_canvas,
                          const gfx::Rect& clip,
                          gfx::RectF* opaque) {
  TRACE_EVENT0("ui", "Layer::PaintContents");
  scoped_ptr<gfx::Canvas> canvas(gfx::Canvas::CreateCanvasWithoutScaling(
      sk_canvas, device_scale_factor_));

  bool scale_content = scale_content_;
  if (scale_content) {
    canvas->Save();
    canvas->sk_canvas()->scale(SkFloatToScalar(device_scale_factor_),
                               SkFloatToScalar(device_scale_factor_));
  }

  if (delegate_)
    delegate_->OnPaintLayer(canvas.get());
  if (scale_content)
    canvas->Restore();
}

bool Layer::FillsBoundsCompletely() const { return fills_bounds_completely_; }

unsigned Layer::PrepareTexture() {
  DCHECK(texture_layer_.get());
  return texture_->PrepareTexture();
}

bool Layer::PrepareTextureMailbox(
    cc::TextureMailbox* mailbox,
    scoped_ptr<cc::SingleReleaseCallback>* release_callback,
    bool use_shared_memory) {
  return false;
}

void Layer::SetForceRenderSurface(bool force) {
  if (force_render_surface_ == force)
    return;

  force_render_surface_ = force;
  cc_layer_->SetForceRenderSurface(force_render_surface_);
}

class LayerDebugInfo : public base::debug::ConvertableToTraceFormat {
 public:
  explicit LayerDebugInfo(std::string name) : name_(name) { }
  virtual void AppendAsTraceFormat(std::string* out) const OVERRIDE {
    base::DictionaryValue dictionary;
    dictionary.SetString("layer_name", name_);
    base::JSONWriter::Write(&dictionary, out);
  }

 private:
  virtual ~LayerDebugInfo() { }
  std::string name_;
};

scoped_refptr<base::debug::ConvertableToTraceFormat> Layer::TakeDebugInfo() {
  return new LayerDebugInfo(name_);
}

void Layer::OnAnimationStarted(const cc::AnimationEvent& event) {
  if (animator_.get())
    animator_->OnThreadedAnimationStarted(event);
}

void Layer::StackRelativeTo(Layer* child, Layer* other, bool above) {
  DCHECK_NE(child, other);
  DCHECK_EQ(this, child->parent());
  DCHECK_EQ(this, other->parent());

  const size_t child_i =
      std::find(children_.begin(), children_.end(), child) - children_.begin();
  const size_t other_i =
      std::find(children_.begin(), children_.end(), other) - children_.begin();
  if ((above && child_i == other_i + 1) || (!above && child_i + 1 == other_i))
    return;

  const size_t dest_i =
      above ?
      (child_i < other_i ? other_i : other_i + 1) :
      (child_i < other_i ? other_i - 1 : other_i);
  children_.erase(children_.begin() + child_i);
  children_.insert(children_.begin() + dest_i, child);

  child->cc_layer_->RemoveFromParent();
  cc_layer_->InsertChild(child->cc_layer_, dest_i);
}

bool Layer::ConvertPointForAncestor(const Layer* ancestor,
                                    gfx::Point* point) const {
  gfx::Transform transform;
  bool result = GetTargetTransformRelativeTo(ancestor, &transform);
  gfx::Point3F p(*point);
  transform.TransformPoint(&p);
  *point = gfx::ToFlooredPoint(p.AsPointF());
  return result;
}

bool Layer::ConvertPointFromAncestor(const Layer* ancestor,
                                     gfx::Point* point) const {
  gfx::Transform transform;
  bool result = GetTargetTransformRelativeTo(ancestor, &transform);
  gfx::Point3F p(*point);
  transform.TransformPointReverse(&p);
  *point = gfx::ToFlooredPoint(p.AsPointF());
  return result;
}

void Layer::SetBoundsFromAnimation(const gfx::Rect& bounds) {
  if (bounds == bounds_)
    return;

  base::Closure closure;
  if (delegate_)
    closure = delegate_->PrepareForLayerBoundsChange();
  bool was_move = bounds_.size() == bounds.size();
  bounds_ = bounds;

  RecomputeDrawsContentAndUVRect();
  RecomputePosition();

  if (!closure.is_null())
    closure.Run();

  if (was_move) {
    // Don't schedule a draw if we're invisible. We'll schedule one
    // automatically when we get visible.
    if (IsDrawn())
      ScheduleDraw();
  } else {
    // Always schedule a paint, even if we're invisible.
    SchedulePaint(gfx::Rect(bounds.size()));
  }
}

void Layer::SetTransformFromAnimation(const gfx::Transform& transform) {
  RecomputeCCTransformFromTransform(transform);
}

void Layer::SetOpacityFromAnimation(float opacity) {
  cc_layer_->SetOpacity(opacity);
  ScheduleDraw();
}

void Layer::SetVisibilityFromAnimation(bool visible) {
  if (visible_ == visible)
    return;

  visible_ = visible;
  cc_layer_->SetHideLayerAndSubtree(!visible_);
}

void Layer::SetBrightnessFromAnimation(float brightness) {
  layer_brightness_ = brightness;
  SetLayerFilters();
}

void Layer::SetGrayscaleFromAnimation(float grayscale) {
  layer_grayscale_ = grayscale;
  SetLayerFilters();
}

void Layer::SetColorFromAnimation(SkColor color) {
  DCHECK_EQ(type_, LAYER_SOLID_COLOR);
  solid_color_layer_->SetBackgroundColor(color);
  SetFillsBoundsOpaquely(SkColorGetA(color) == 0xFF);
}

void Layer::ScheduleDrawForAnimation() {
  ScheduleDraw();
}

const gfx::Rect& Layer::GetBoundsForAnimation() const {
  return bounds();
}

gfx::Transform Layer::GetTransformForAnimation() const {
  return transform();
}

float Layer::GetOpacityForAnimation() const {
  return opacity();
}

bool Layer::GetVisibilityForAnimation() const {
  return visible();
}

float Layer::GetBrightnessForAnimation() const {
  return layer_brightness();
}

float Layer::GetGrayscaleForAnimation() const {
  return layer_grayscale();
}

SkColor Layer::GetColorForAnimation() const {
  // WebColor is equivalent to SkColor, per WebColor.h.
  // The NULL check is here since this is invoked regardless of whether we have
  // been configured as LAYER_SOLID_COLOR.
  return solid_color_layer_.get() ?
      solid_color_layer_->background_color() : SK_ColorBLACK;
}

float Layer::GetDeviceScaleFactor() const {
  return device_scale_factor_;
}

void Layer::AddThreadedAnimation(scoped_ptr<cc::Animation> animation) {
  DCHECK(cc_layer_);
  // Until this layer has a compositor (and hence cc_layer_ has a
  // LayerTreeHost), addAnimation will fail.
  if (GetCompositor())
    cc_layer_->AddAnimation(animation.Pass());
  else
    pending_threaded_animations_.push_back(animation.Pass());
}

namespace{

struct HasAnimationId {
  HasAnimationId(int id): id_(id) {
  }

  bool operator()(cc::Animation* animation) const {
    return animation->id() == id_;
  }

 private:
  int id_;
};

}

void Layer::RemoveThreadedAnimation(int animation_id) {
  DCHECK(cc_layer_);
  if (pending_threaded_animations_.size() == 0) {
    cc_layer_->RemoveAnimation(animation_id);
    return;
  }

  pending_threaded_animations_.erase(
      cc::remove_if(&pending_threaded_animations_,
                    pending_threaded_animations_.begin(),
                    pending_threaded_animations_.end(),
                    HasAnimationId(animation_id)),
      pending_threaded_animations_.end());
}

void Layer::SendPendingThreadedAnimations() {
  for (cc::ScopedPtrVector<cc::Animation>::iterator it =
           pending_threaded_animations_.begin();
       it != pending_threaded_animations_.end();
       ++it)
    cc_layer_->AddAnimation(pending_threaded_animations_.take(it));

  pending_threaded_animations_.clear();

  for (size_t i = 0; i < children_.size(); ++i)
    children_[i]->SendPendingThreadedAnimations();
}

void Layer::CreateWebLayer() {
  if (type_ == LAYER_SOLID_COLOR) {
    solid_color_layer_ = cc::SolidColorLayer::Create();
    cc_layer_ = solid_color_layer_.get();
  } else {
    if (Layer::UsingPictureLayer())
      content_layer_ = cc::PictureLayer::Create(this);
    else
      content_layer_ = cc::ContentLayer::Create(this);
    cc_layer_ = content_layer_.get();
  }
  cc_layer_->SetAnchorPoint(gfx::PointF());
  cc_layer_->SetContentsOpaque(true);
  cc_layer_->SetIsDrawable(type_ != LAYER_NOT_DRAWN);
  cc_layer_->AddLayerAnimationEventObserver(this);
  cc_layer_->SetLayerClient(this);
  RecomputePosition();
}

void Layer::RecomputeCCTransformFromTransform(const gfx::Transform& transform) {
  cc_layer_->SetTransform(ConvertTransformToCCTransform(transform,
                                                        device_scale_factor_));
}

gfx::Transform Layer::transform() const {
  gfx::Transform transform;
  transform.Scale(1.0f / device_scale_factor_, 1.0f / device_scale_factor_);
  transform.PreconcatTransform(cc_layer_->transform());
  transform.Scale(device_scale_factor_, device_scale_factor_);
  return transform;
}

void Layer::RecomputeDrawsContentAndUVRect() {
  DCHECK(cc_layer_);
  gfx::Size size(bounds_.size());
  if (texture_layer_.get()) {
    gfx::Size texture_size;
    if (!texture_layer_->uses_mailbox()) {
      DCHECK(texture_.get());
      float texture_scale_factor = 1.0f / texture_->device_scale_factor();
      texture_size = gfx::ToFlooredSize(
          gfx::ScaleSize(texture_->size(), texture_scale_factor));
    } else {
      DCHECK(mailbox_.IsSharedMemory());
      float texture_scale_factor = 1.0f / mailbox_scale_factor_;
      texture_size = gfx::ToFlooredSize(
          gfx::ScaleSize(mailbox_.shared_memory_size(), texture_scale_factor));
    }
    size.SetToMin(texture_size);

    gfx::PointF uv_top_left(0.f, 0.f);
    gfx::PointF uv_bottom_right(
        static_cast<float>(size.width())/texture_size.width(),
        static_cast<float>(size.height())/texture_size.height());
    texture_layer_->SetUV(uv_top_left, uv_bottom_right);
  } else if (delegated_renderer_layer_.get()) {
    delegated_renderer_layer_->SetDisplaySize(
        ConvertSizeToPixel(this, delegated_frame_size_in_dip_));
    size.SetToMin(delegated_frame_size_in_dip_);
  }
  cc_layer_->SetBounds(ConvertSizeToPixel(this, size));
}

void Layer::RecomputePosition() {
  cc_layer_->SetPosition(gfx::ScalePoint(
        gfx::PointF(bounds_.x(), bounds_.y()),
        device_scale_factor_));
}

}  // namespace ui