Google Git
Sign in
chromium / chromium / src / 2fcda9488b475cdf535e5a24e83fac563c448db4 / . / third_party / blink / renderer / core / paint / paint_property_tree_builder.cc
blob: 48c4c261dda9a93d4758e8bd126bdcf86ad78b22 [file] [log] [blame]
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "third_party/blink/renderer/core/paint/paint_property_tree_builder.h"
#include <memory>
#include "base/check_op.h"
#include "base/memory/ptr_util.h"
#include "cc/input/main_thread_scrolling_reason.h"
#include "cc/input/overscroll_behavior.h"
#include "third_party/blink/renderer/core/animation/element_animations.h"
#include "third_party/blink/renderer/core/document_transition/document_transition.h"
#include "third_party/blink/renderer/core/document_transition/document_transition_supplement.h"
#include "third_party/blink/renderer/core/dom/dom_node_ids.h"
#include "third_party/blink/renderer/core/frame/local_frame.h"
#include "third_party/blink/renderer/core/frame/local_frame_client.h"
#include "third_party/blink/renderer/core/frame/local_frame_view.h"
#include "third_party/blink/renderer/core/frame/settings.h"
#include "third_party/blink/renderer/core/frame/visual_viewport.h"
#include "third_party/blink/renderer/core/layout/fragmentainer_iterator.h"
#include "third_party/blink/renderer/core/layout/geometry/transform_state.h"
#include "third_party/blink/renderer/core/layout/geometry/writing_mode_converter.h"
#include "third_party/blink/renderer/core/layout/layout_embedded_content.h"
#include "third_party/blink/renderer/core/layout/layout_image.h"
#include "third_party/blink/renderer/core/layout/layout_inline.h"
#include "third_party/blink/renderer/core/layout/layout_object.h"
#include "third_party/blink/renderer/core/layout/layout_replaced.h"
#include "third_party/blink/renderer/core/layout/layout_table_row.h"
#include "third_party/blink/renderer/core/layout/layout_table_section.h"
#include "third_party/blink/renderer/core/layout/layout_video.h"
#include "third_party/blink/renderer/core/layout/layout_view.h"
#include "third_party/blink/renderer/core/layout/ng/inline/ng_fragment_item.h"
#include "third_party/blink/renderer/core/layout/ng/ng_block_break_token.h"
#include "third_party/blink/renderer/core/layout/ng/ng_fragmentation_utils.h"
#include "third_party/blink/renderer/core/layout/ng/ng_physical_box_fragment.h"
#include "third_party/blink/renderer/core/layout/svg/layout_svg_resource_masker.h"
#include "third_party/blink/renderer/core/layout/svg/layout_svg_root.h"
#include "third_party/blink/renderer/core/layout/svg/layout_svg_viewport_container.h"
#include "third_party/blink/renderer/core/layout/svg/svg_layout_support.h"
#include "third_party/blink/renderer/core/layout/svg/svg_resources.h"
#include "third_party/blink/renderer/core/layout/svg/transform_helper.h"
#include "third_party/blink/renderer/core/page/link_highlight.h"
#include "third_party/blink/renderer/core/page/page.h"
#include "third_party/blink/renderer/core/page/scrolling/snap_coordinator.h"
#include "third_party/blink/renderer/core/page/scrolling/sticky_position_scrolling_constraints.h"
#include "third_party/blink/renderer/core/page/scrolling/top_document_root_scroller_controller.h"
#include "third_party/blink/renderer/core/paint/clip_path_clipper.h"
#include "third_party/blink/renderer/core/paint/compositing/compositing_reason_finder.h"
#include "third_party/blink/renderer/core/paint/css_mask_painter.h"
#include "third_party/blink/renderer/core/paint/cull_rect_updater.h"
#include "third_party/blink/renderer/core/paint/find_paint_offset_needing_update.h"
#include "third_party/blink/renderer/core/paint/find_properties_needing_update.h"
#include "third_party/blink/renderer/core/paint/object_paint_properties.h"
#include "third_party/blink/renderer/core/paint/paint_layer.h"
#include "third_party/blink/renderer/core/paint/paint_layer_scrollable_area.h"
#include "third_party/blink/renderer/core/paint/paint_property_tree_printer.h"
#include "third_party/blink/renderer/core/paint/rounded_border_geometry.h"
#include "third_party/blink/renderer/core/paint/svg_root_painter.h"
#include "third_party/blink/renderer/core/style/computed_style_base_constants.h"
#include "third_party/blink/renderer/core/style/computed_style_constants.h"
#include "third_party/blink/renderer/core/style/style_overflow_clip_margin.h"
#include "third_party/blink/renderer/platform/geometry/layout_rect_outsets.h"
#include "third_party/blink/renderer/platform/geometry/layout_unit.h"
#include "third_party/blink/renderer/platform/graphics/compositing/paint_artifact_compositor.h"
#include "third_party/blink/renderer/platform/graphics/document_transition_shared_element_id.h"
#include "third_party/blink/renderer/platform/graphics/paint/effect_paint_property_node.h"
#include "third_party/blink/renderer/platform/graphics/skia/skia_utils.h"
#include "third_party/blink/renderer/platform/transforms/transformation_matrix.h"
#include "third_party/blink/renderer/platform/wtf/casting.h"
#include "ui/gfx/geometry/outsets_f.h"
#include "ui/gfx/geometry/vector2d_conversions.h"
namespace blink {
namespace {
bool AreSubtreeUpdateReasonsIsolationPiercing(unsigned reasons) {
// This is written to mean that if we have any reason other than the specified
// ones then the reasons are isolation piercing. This means that if new
// reasons are added, they will be isolation piercing by default.
// - Isolation establishes a containing block for all descendants, so it is
// not piercing.
// TODO(vmpstr): Investigate if transform style is also isolated.
return reasons &
~(static_cast<unsigned>(
SubtreePaintPropertyUpdateReason::kContainerChainMayChange));
}
} // namespace
PaintPropertyTreeBuilderFragmentContext::
PaintPropertyTreeBuilderFragmentContext()
: current_effect(&EffectPaintPropertyNode::Root()) {
current.clip = absolute_position.clip = fixed_position.clip =
&ClipPaintPropertyNode::Root();
current.transform = absolute_position.transform = fixed_position.transform =
&TransformPaintPropertyNode::Root();
current.scroll = absolute_position.scroll = fixed_position.scroll =
&ScrollPaintPropertyNode::Root();
}
PaintPropertyTreeBuilderContext::PaintPropertyTreeBuilderContext()
: force_subtree_update_reasons(0u),
is_repeating_fixed_position(false),
has_svg_hidden_container_ancestor(false),
was_layout_shift_root(false),
was_main_thread_scrolling(false) {}
PaintPropertyTreeBuilderContext::~PaintPropertyTreeBuilderContext() {
fragments.clear();
}
void PaintPropertyTreeBuilderFragmentContext::Trace(Visitor* visitor) const {
visitor->Trace(current);
visitor->Trace(absolute_position);
visitor->Trace(fixed_position);
}
void PaintPropertyTreeBuilderFragmentContext::ContainingBlockContext::Trace(
Visitor* visitor) const {
visitor->Trace(paint_offset_root);
}
void VisualViewportPaintPropertyTreeBuilder::Update(
LocalFrameView& main_frame_view,
VisualViewport& visual_viewport,
PaintPropertyTreeBuilderContext& full_context) {
if (full_context.fragments.IsEmpty())
full_context.fragments.push_back(PaintPropertyTreeBuilderFragmentContext());
PaintPropertyTreeBuilderFragmentContext& context = full_context.fragments[0];
auto property_changed =
visual_viewport.UpdatePaintPropertyNodesIfNeeded(context);
if (const EffectPaintPropertyNode* overscroll_elasticity_effect_node =
visual_viewport.GetOverscrollElasticityEffectNode()) {
context.current_effect = overscroll_elasticity_effect_node;
}
context.current.transform = visual_viewport.GetScrollTranslationNode();
context.absolute_position.transform =
visual_viewport.GetScrollTranslationNode();
context.fixed_position.transform = visual_viewport.GetScrollTranslationNode();
context.current.scroll = visual_viewport.GetScrollNode();
context.absolute_position.scroll = visual_viewport.GetScrollNode();
context.fixed_position.scroll = visual_viewport.GetScrollNode();
if (property_changed >= PaintPropertyChangeType::kNodeAddedOrRemoved) {
// Force piercing subtree update for the worst case (scroll node added/
// removed). Not a big deal for performance because this is rare.
full_context.force_subtree_update_reasons |=
PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationPiercing;
// The main frame's paint chunks (e.g. scrollbars) may reference paint
// properties of the visual viewport.
if (auto* layout_view = main_frame_view.GetLayoutView())
layout_view->Layer()->SetNeedsRepaint();
}
if (property_changed >
PaintPropertyChangeType::kChangedOnlyCompositedValues) {
main_frame_view.SetPaintArtifactCompositorNeedsUpdate(
PaintArtifactCompositorUpdateReason::
kVisualViewportPaintPropertyTreeBuilderUpdate);
}
#if DCHECK_IS_ON()
paint_property_tree_printer::UpdateDebugNames(visual_viewport);
#endif
}
void PaintPropertyTreeBuilder::SetupContextForFrame(
LocalFrameView& frame_view,
PaintPropertyTreeBuilderContext& full_context) {
if (full_context.fragments.IsEmpty())
full_context.fragments.push_back(PaintPropertyTreeBuilderFragmentContext());
PaintPropertyTreeBuilderFragmentContext& context = full_context.fragments[0];
// Block fragmentation doesn't cross frame boundaries.
full_context.repeating_table_section = nullptr;
context.current.is_in_block_fragmentation = false;
context.current.paint_offset += PhysicalOffset(frame_view.Location());
context.rendering_context_id = 0;
context.should_flatten_inherited_transform = true;
context.absolute_position = context.current;
full_context.container_for_absolute_position = nullptr;
full_context.container_for_fixed_position = nullptr;
context.fixed_position = context.current;
context.fixed_position.fixed_position_children_fixed_to_root = true;
}
namespace {
class FragmentPaintPropertyTreeBuilder {
STACK_ALLOCATED();
public:
FragmentPaintPropertyTreeBuilder(
const LayoutObject& object,
NGPrePaintInfo* pre_paint_info,
PaintPropertyTreeBuilderContext& full_context,
PaintPropertyTreeBuilderFragmentContext& context,
FragmentData& fragment_data)
: object_(object),
pre_paint_info_(pre_paint_info),
full_context_(full_context),
context_(context),
fragment_data_(fragment_data),
properties_(fragment_data.PaintProperties()) {}
#if DCHECK_IS_ON()
~FragmentPaintPropertyTreeBuilder() {
if (properties_)
paint_property_tree_printer::UpdateDebugNames(object_, *properties_);
}
#endif
ALWAYS_INLINE void UpdateForSelf();
ALWAYS_INLINE void UpdateForChildren();
const PaintPropertiesChangeInfo& PropertiesChanged() const {
return properties_changed_;
}
bool HasIsolationNodes() const {
// All or nothing check on the isolation nodes.
DCHECK(!properties_ ||
(properties_->TransformIsolationNode() &&
properties_->ClipIsolationNode() &&
properties_->EffectIsolationNode()) ||
(!properties_->TransformIsolationNode() &&
!properties_->ClipIsolationNode() &&
!properties_->EffectIsolationNode()));
return properties_ && properties_->TransformIsolationNode();
}
private:
ALWAYS_INLINE bool CanPropagateSubpixelAccumulation() const;
ALWAYS_INLINE void UpdatePaintOffset();
ALWAYS_INLINE void UpdateForPaintOffsetTranslation(
absl::optional<gfx::Vector2d>&);
ALWAYS_INLINE void UpdatePaintOffsetTranslation(
const absl::optional<gfx::Vector2d>&);
ALWAYS_INLINE void SetNeedsPaintPropertyUpdateIfNeeded();
ALWAYS_INLINE void UpdateForObjectLocationAndSize(
absl::optional<gfx::Vector2d>& paint_offset_translation);
ALWAYS_INLINE void UpdateStickyTranslation();
ALWAYS_INLINE void UpdateAnchorScrollTranslation();
void UpdateIndividualTransform(
bool (*needs_property)(const LayoutObject&, CompositingReasons),
void (*compute_matrix)(const ComputedStyle& style,
const PhysicalSize& size,
TransformationMatrix& matrix),
CompositingReasons active_animation_reason,
CompositingReasons compositing_reasons_for_property,
CompositorElementIdNamespace compositor_namespace,
bool (ComputedStyle::*running_on_compositor_test)() const,
const TransformPaintPropertyNode* (ObjectPaintProperties::*getter)()
const,
PaintPropertyChangeType (ObjectPaintProperties::*updater)(
const TransformPaintPropertyNodeOrAlias&,
TransformPaintPropertyNode::State&&,
const TransformPaintPropertyNode::AnimationState&),
bool (ObjectPaintProperties::*clearer)());
ALWAYS_INLINE void UpdateTranslate();
ALWAYS_INLINE void UpdateRotate();
ALWAYS_INLINE void UpdateScale();
ALWAYS_INLINE void UpdateOffset();
ALWAYS_INLINE void UpdateTransform();
ALWAYS_INLINE void UpdateTransformForSVGChild(CompositingReasons);
ALWAYS_INLINE bool NeedsEffect() const;
ALWAYS_INLINE bool EffectCanUseCurrentClipAsOutputClip() const;
ALWAYS_INLINE void UpdateSharedElementTransitionEffect();
ALWAYS_INLINE void UpdateEffect();
ALWAYS_INLINE void UpdateFilter();
ALWAYS_INLINE void UpdateFragmentClip();
ALWAYS_INLINE void UpdateCssClip();
ALWAYS_INLINE void UpdateClipPathClip();
ALWAYS_INLINE void UpdateLocalBorderBoxContext();
ALWAYS_INLINE bool NeedsOverflowControlsClip() const;
ALWAYS_INLINE void UpdateOverflowControlsClip();
ALWAYS_INLINE void UpdateInnerBorderRadiusClip();
ALWAYS_INLINE void UpdateOverflowClip();
ALWAYS_INLINE void UpdatePerspective();
ALWAYS_INLINE void UpdateReplacedContentTransform();
ALWAYS_INLINE void UpdateScrollAndScrollTranslation();
ALWAYS_INLINE void UpdateOutOfFlowContext();
// See core/paint/README.md for the description of isolation nodes.
ALWAYS_INLINE void UpdateTransformIsolationNode();
ALWAYS_INLINE void UpdateEffectIsolationNode();
ALWAYS_INLINE void UpdateClipIsolationNode();
ALWAYS_INLINE void SetTransformNodeStateForSVGChild(
TransformPaintPropertyNode::State&);
ALWAYS_INLINE void UpdateLayoutShiftRootChanged(bool is_layout_shift_root);
bool NeedsPaintPropertyUpdate() const {
return object_.NeedsPaintPropertyUpdate() ||
full_context_.force_subtree_update_reasons;
}
bool IsInNGFragmentTraversal() const { return pre_paint_info_; }
void SwitchToOOFContext(
PaintPropertyTreeBuilderFragmentContext::ContainingBlockContext&
oof_context) const {
context_.current = oof_context;
// If we're not block-fragmented, simply setting a new context is all we
// have to do.
if (!oof_context.is_in_block_fragmentation)
return;
// Inside NG block fragmentation we have to perform an offset adjustment.
// An OOF fragment that is contained by something inside a fragmentainer
// will be a direct child of the fragmentainer, rather than a child of its
// actual containing block. Set the paint offset to the correct one.
context_.current.paint_offset =
context_.current.paint_offset_for_oof_in_fragmentainer;
}
void ResetPaintOffset(PhysicalOffset new_offset = PhysicalOffset()) {
context_.current.paint_offset_for_oof_in_fragmentainer -=
context_.current.paint_offset - new_offset;
context_.current.paint_offset = new_offset;
}
void OnUpdateTransform(PaintPropertyChangeType change) {
properties_changed_.transform_changed =
std::max(properties_changed_.transform_changed, change);
}
void OnClearTransform(bool cleared) {
if (cleared) {
properties_changed_.transform_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
}
void OnUpdateClip(PaintPropertyChangeType change) {
properties_changed_.clip_changed =
std::max(properties_changed_.clip_changed, change);
}
void OnClearClip(bool cleared) {
if (cleared) {
properties_changed_.clip_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
}
void OnUpdateEffect(PaintPropertyChangeType change) {
properties_changed_.effect_changed =
std::max(properties_changed_.effect_changed, change);
}
void OnClearEffect(bool cleared) {
if (cleared) {
properties_changed_.effect_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
}
void OnUpdateScroll(PaintPropertyChangeType change) {
properties_changed_.scroll_changed =
std::max(properties_changed_.scroll_changed, change);
}
void OnClearScroll(bool cleared) {
if (cleared) {
properties_changed_.scroll_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
}
CompositorElementId GetCompositorElementId(
CompositorElementIdNamespace namespace_id) const {
return CompositorElementIdFromUniqueObjectId(fragment_data_.UniqueId(),
namespace_id);
}
const LayoutObject& object_;
NGPrePaintInfo* pre_paint_info_;
// The tree builder context for the whole object.
PaintPropertyTreeBuilderContext& full_context_;
// The tree builder context for the current fragment, which is one of the
// entries in |full_context.fragments|.
PaintPropertyTreeBuilderFragmentContext& context_;
FragmentData& fragment_data_;
ObjectPaintProperties* properties_;
PaintPropertiesChangeInfo properties_changed_;
// These are updated in UpdateClipPathClip() and used in UpdateEffect() if
// needs_mask_base_clip_path_ is true.
bool needs_mask_based_clip_path_ = false;
absl::optional<gfx::RectF> clip_path_bounding_box_;
};
// True if a scroll translation is needed for static scroll offset (e.g.,
// overflow hidden with scroll), or if a scroll node is needed for composited
// scrolling.
static bool NeedsScrollOrScrollTranslation(
const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
if (!object.IsScrollContainer())
return false;
const LayoutBox& box = To<LayoutBox>(object);
if (!box.GetScrollableArea())
return false;
ScrollOffset scroll_offset = box.GetScrollableArea()->GetScrollOffset();
return !scroll_offset.IsZero() ||
box.NeedsScrollNode(direct_compositing_reasons);
}
static bool NeedsReplacedContentTransform(const LayoutObject& object) {
if (object.IsSVGRoot())
return true;
if (auto* layout_embedded_object = DynamicTo<LayoutEmbeddedContent>(object))
return layout_embedded_object->FrozenFrameSize().has_value();
return false;
}
static bool NeedsPaintOffsetTranslationForOverflowControls(
const LayoutBoxModelObject& object) {
if (auto* area = object.GetScrollableArea()) {
if (area->HorizontalScrollbar() || area->VerticalScrollbar() ||
area->Resizer()) {
return true;
}
}
return false;
}
static bool NeedsIsolationNodes(const LayoutObject& object) {
if (!object.HasLayer())
return false;
// Paint containment establishes isolation.
// Style & Layout containment also establish isolation.
if (object.ShouldApplyPaintContainment() ||
(object.ShouldApplyStyleContainment() &&
object.ShouldApplyLayoutContainment())) {
return true;
}
// Layout view establishes isolation with the exception of local roots (since
// they are already essentially isolated).
if (IsA<LayoutView>(object)) {
const auto* parent_frame = object.GetFrame()->Tree().Parent();
return IsA<LocalFrame>(parent_frame);
}
return false;
}
static bool NeedsStickyTranslation(const LayoutObject& object) {
if (!object.IsBoxModelObject())
return false;
return To<LayoutBoxModelObject>(object).StickyConstraints();
}
static bool NeedsAnchorScrollTranslation(const LayoutObject& object) {
if (const LayoutBox* box = DynamicTo<LayoutBox>(object))
return box->AnchorScrollContainer();
return false;
}
static bool NeedsPaintOffsetTranslation(
const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
if (!object.IsBoxModelObject())
return false;
// An SVG children inherits no paint offset, because there is no such concept
// within SVG. Though <foreignObject> can have its own paint offset due to the
// x and y parameters of the element, which affects the offset of painting of
// the <foreignObject> element and its children, it still behaves like other
// SVG elements, in that the x and y offset is applied *after* any transform,
// instead of before.
if (object.IsSVGChild())
return false;
const auto& box_model = To<LayoutBoxModelObject>(object);
if (IsA<LayoutView>(box_model)) {
// A translation node for LayoutView is always created to ensure fixed and
// absolute contexts use the correct transform space.
return true;
}
if (NeedsIsolationNodes(box_model)) {
DCHECK(box_model.HasLayer());
return true;
}
if (box_model.HasTransform())
return true;
if (NeedsScrollOrScrollTranslation(object, direct_compositing_reasons))
return true;
if (NeedsStickyTranslation(object))
return true;
if (NeedsAnchorScrollTranslation(object))
return true;
if (NeedsPaintOffsetTranslationForOverflowControls(box_model))
return true;
if (NeedsReplacedContentTransform(object))
return true;
// Reference filter and reflection (which creates a reference filter) requires
// zero paint offset.
if (box_model.HasLayer() &&
(object.StyleRef().Filter().HasReferenceFilter() ||
object.HasReflection()))
return true;
// Though we don't treat hidden backface as a direct compositing reason, it's
// very likely that the object will be composited, so a paint offset
// translation will be beneficial.
bool has_paint_offset_compositing_reason =
direct_compositing_reasons != CompositingReason::kNone ||
box_model.StyleRef().BackfaceVisibility() == EBackfaceVisibility::kHidden;
if (has_paint_offset_compositing_reason) {
// Don't let paint offset cross composited layer boundaries when possible,
// to avoid unnecessary full layer paint/raster invalidation when paint
// offset in ancestor transform node changes which should not affect the
// descendants of the composited layer. For now because of
// crbug.com/780242, this is limited to LayoutBlocks and LayoutReplaceds
// that won't be escaped by floating objects and column spans when finding
// their containing blocks. TODO(crbug.com/780242): This can be avoided if
// we have fully correct paint property tree states for floating objects
// and column spans.
if (box_model.IsLayoutBlock() || object.IsLayoutReplaced()) {
if (!object.PaintingLayer()->EnclosingPaginationLayer())
return true;
}
}
return false;
}
bool FragmentPaintPropertyTreeBuilder::CanPropagateSubpixelAccumulation()
const {
if (!object_.HasLayer())
return true;
if (full_context_.direct_compositing_reasons &
CompositingReason::kPreventingSubpixelAccumulationReasons) {
return false;
}
if (full_context_.direct_compositing_reasons &
(CompositingReason::kActiveTransformAnimation |
CompositingReason::kActiveRotateAnimation |
CompositingReason::kActiveScaleAnimation)) {
if (const auto* element = DynamicTo<Element>(object_.GetNode())) {
DCHECK(element->GetElementAnimations());
return element->GetElementAnimations()->IsIdentityOrTranslation();
}
return false;
}
const PaintLayer* layer = To<LayoutBoxModelObject>(object_).Layer();
return !layer->Transform() || layer->Transform()->IsIdentityOrTranslation();
}
void FragmentPaintPropertyTreeBuilder::UpdateForPaintOffsetTranslation(
absl::optional<gfx::Vector2d>& paint_offset_translation) {
if (!NeedsPaintOffsetTranslation(
object_, full_context_.direct_compositing_reasons))
return;
// We should use the same subpixel paint offset values for snapping regardless
// of paint offset translation. If we create a paint offset translation we
// round the paint offset but keep around the residual fractional component
// (i.e. subpixel accumulation) for the transformed content to paint with.
paint_offset_translation = ToRoundedVector2d(context_.current.paint_offset);
// Don't propagate subpixel accumulation through paint isolation.
if (NeedsIsolationNodes(object_)) {
ResetPaintOffset();
context_.current.directly_composited_container_paint_offset_subpixel_delta =
PhysicalOffset();
return;
}
PhysicalOffset subpixel_accumulation =
context_.current.paint_offset - PhysicalOffset(*paint_offset_translation);
if (!subpixel_accumulation.IsZero() ||
!context_.current
.directly_composited_container_paint_offset_subpixel_delta
.IsZero()) {
// If the object has a non-translation transform, discard the fractional
// paint offset which can't be transformed by the transform.
if (!CanPropagateSubpixelAccumulation()) {
ResetPaintOffset();
context_.current
.directly_composited_container_paint_offset_subpixel_delta =
PhysicalOffset();
return;
}
}
ResetPaintOffset(subpixel_accumulation);
if (full_context_.direct_compositing_reasons == CompositingReason::kNone)
return;
if (paint_offset_translation && properties_ &&
properties_->PaintOffsetTranslation()) {
// The composited subpixel movement optimization applies only if the
// composited layer has and had PaintOffsetTranslation, so that both the
// the old and new paint offsets are just subpixel accumulations.
DCHECK_EQ(gfx::Point(), ToRoundedPoint(fragment_data_.PaintOffset()));
context_.current.directly_composited_container_paint_offset_subpixel_delta =
context_.current.paint_offset - fragment_data_.PaintOffset();
} else {
// Otherwise disable the optimization.
context_.current.directly_composited_container_paint_offset_subpixel_delta =
PhysicalOffset();
}
}
void FragmentPaintPropertyTreeBuilder::UpdatePaintOffsetTranslation(
const absl::optional<gfx::Vector2d>& paint_offset_translation) {
DCHECK(properties_);
if (paint_offset_translation) {
TransformPaintPropertyNode::State state{
gfx::Vector2dF(*paint_offset_translation)};
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
state.rendering_context_id = context_.rendering_context_id;
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kDirectReasonsForPaintOffsetTranslationProperty;
if (state.direct_compositing_reasons & CompositingReason::kFixedPosition &&
object_.View()->FirstFragment().PaintProperties()->Scroll()) {
state.scroll_translation_for_fixed = object_.View()
->FirstFragment()
.PaintProperties()
->ScrollTranslation();
}
if (IsA<LayoutView>(object_)) {
DCHECK(object_.GetFrame());
state.flags.is_frame_paint_offset_translation = true;
state.visible_frame_element_id =
object_.GetFrame()->GetVisibleToHitTesting()
? CompositorElementIdFromUniqueObjectId(
DOMNodeIds::IdForNode(&object_.GetDocument()),
CompositorElementIdNamespace::kDOMNodeId)
: cc::ElementId();
}
OnUpdateTransform(properties_->UpdatePaintOffsetTranslation(
*context_.current.transform, std::move(state)));
context_.current.transform = properties_->PaintOffsetTranslation();
if (IsA<LayoutView>(object_)) {
context_.absolute_position.transform =
properties_->PaintOffsetTranslation();
context_.fixed_position.transform = properties_->PaintOffsetTranslation();
}
if (!object_.ShouldAssumePaintOffsetTranslationForLayoutShiftTracking()) {
context_.current.additional_offset_to_layout_shift_root_delta +=
PhysicalOffset(*paint_offset_translation);
}
} else {
OnClearTransform(properties_->ClearPaintOffsetTranslation());
}
}
void FragmentPaintPropertyTreeBuilder::UpdateStickyTranslation() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsStickyTranslation(object_)) {
const auto& box_model = To<LayoutBoxModelObject>(object_);
TransformPaintPropertyNode::State state{
gfx::Vector2dF(box_model.StickyPositionOffset())};
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kStickyPosition;
// TODO(wangxianzhu): Not using GetCompositorElementId() here because
// sticky elements don't work properly under multicol for now, to keep
// consistency with CompositorElementIdFromUniqueObjectId() below.
// This will be fixed by LayoutNG block fragments.
state.compositor_element_id = CompositorElementIdFromUniqueObjectId(
box_model.UniqueId(),
CompositorElementIdNamespace::kStickyTranslation);
state.rendering_context_id = context_.rendering_context_id;
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
if (state.direct_compositing_reasons) {
const auto* layout_constraint = box_model.StickyConstraints();
DCHECK(layout_constraint);
const auto* scroll_container_properties =
layout_constraint->containing_scroll_container_layer
->GetLayoutObject()
.FirstFragment()
.PaintProperties();
// A scroll node is only created if an object can be scrolled manually,
// while sticky position attaches to anything that clips overflow.
// No need to (actually can't) setup composited sticky constraint if
// the clipping ancestor we attach to doesn't have a scroll node.
bool scroll_container_scrolls =
scroll_container_properties &&
scroll_container_properties->Scroll() == context_.current.scroll;
if (scroll_container_scrolls) {
auto constraint = std::make_unique<CompositorStickyConstraint>();
constraint->is_anchored_left = layout_constraint->is_anchored_left;
constraint->is_anchored_right = layout_constraint->is_anchored_right;
constraint->is_anchored_top = layout_constraint->is_anchored_top;
constraint->is_anchored_bottom =
layout_constraint->is_anchored_bottom;
constraint->left_offset = layout_constraint->left_offset.ToFloat();
constraint->right_offset = layout_constraint->right_offset.ToFloat();
constraint->top_offset = layout_constraint->top_offset.ToFloat();
constraint->bottom_offset =
layout_constraint->bottom_offset.ToFloat();
constraint->constraint_box_rect =
gfx::RectF(layout_constraint->constraining_rect);
constraint->scroll_container_relative_sticky_box_rect = gfx::RectF(
layout_constraint->scroll_container_relative_sticky_box_rect);
constraint->scroll_container_relative_containing_block_rect =
gfx::RectF(layout_constraint
->scroll_container_relative_containing_block_rect);
if (const PaintLayer* sticky_box_shifting_ancestor =
layout_constraint->nearest_sticky_layer_shifting_sticky_box) {
constraint->nearest_element_shifting_sticky_box =
CompositorElementIdFromUniqueObjectId(
sticky_box_shifting_ancestor->GetLayoutObject().UniqueId(),
CompositorElementIdNamespace::kStickyTranslation);
}
if (const PaintLayer* containing_block_shifting_ancestor =
layout_constraint
->nearest_sticky_layer_shifting_containing_block) {
constraint->nearest_element_shifting_containing_block =
CompositorElementIdFromUniqueObjectId(
containing_block_shifting_ancestor->GetLayoutObject()
.UniqueId(),
CompositorElementIdNamespace::kStickyTranslation);
}
state.sticky_constraint = std::move(constraint);
}
}
OnUpdateTransform(properties_->UpdateStickyTranslation(
*context_.current.transform, std::move(state)));
} else {
OnClearTransform(properties_->ClearStickyTranslation());
}
}
if (properties_->StickyTranslation())
context_.current.transform = properties_->StickyTranslation();
}
void FragmentPaintPropertyTreeBuilder::UpdateAnchorScrollTranslation() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsAnchorScrollTranslation(object_)) {
const auto& box = To<LayoutBox>(object_);
LayoutBox::AnchorScrollData anchor_scroll_data =
box.ComputeAnchorScrollData();
gfx::Vector2dF translation_offset =
-anchor_scroll_data.accumulated_scroll_offset;
TransformPaintPropertyNode::State state{translation_offset};
DCHECK(full_context_.direct_compositing_reasons &
CompositingReason::kAnchorScroll);
state.direct_compositing_reasons = CompositingReason::kAnchorScroll;
// TODO(crbug.com/1309178): Not using GetCompositorElementId() here
// because anchor-positioned elements don't work properly under multicol
// for now, to keep consistency with
// CompositorElementIdFromUniqueObjectId() below. This will be fixed by
// LayoutNG block fragments.
state.compositor_element_id = CompositorElementIdFromUniqueObjectId(
box.UniqueId(),
CompositorElementIdNamespace::kAnchorScrollTranslation);
state.rendering_context_id = context_.rendering_context_id;
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
scoped_refptr<const TransformPaintPropertyNode>
inner_most_scroll_container =
anchor_scroll_data.inner_most_scroll_container_layer
->GetLayoutObject()
.FirstFragment()
.PaintProperties()
->ScrollTranslation();
scoped_refptr<const TransformPaintPropertyNode>
outer_most_scroll_container =
anchor_scroll_data.outer_most_scroll_container_layer
->GetLayoutObject()
.FirstFragment()
.PaintProperties()
->ScrollTranslation();
state.anchor_scroll_containers_data = std::make_unique<
TransformPaintPropertyNode::AnchorScrollContainersData>(
std::move(inner_most_scroll_container),
std::move(outer_most_scroll_container),
anchor_scroll_data.accumulated_scroll_origin);
OnUpdateTransform(properties_->UpdateAnchorScrollTranslation(
*context_.current.transform, std::move(state)));
} else {
OnClearTransform(properties_->ClearAnchorScrollTranslation());
}
}
if (properties_->AnchorScrollTranslation())
context_.current.transform = properties_->AnchorScrollTranslation();
}
// TODO(dbaron): Remove this function when we can remove the
// BackfaceVisibilityInteropEnabled() check, and have the caller use
// CompositingReason::kDirectReasonsForTransformProperty directly.
static CompositingReasons CompositingReasonsForTransformProperty() {
CompositingReasons reasons =
CompositingReason::kDirectReasonsForTransformProperty;
if (RuntimeEnabledFeatures::BackfaceVisibilityInteropEnabled())
reasons |= CompositingReason::kBackfaceInvisibility3DAncestor;
return reasons;
}
// TODO(crbug.com/1278452): Merge SVG handling into the primary codepath.
static bool NeedsTransformForSVGChild(
const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
if (!object.IsSVGChild() || object.IsText())
return false;
if (direct_compositing_reasons &
(CompositingReasonsForTransformProperty() |
CompositingReason::kDirectReasonsForTranslateProperty |
CompositingReason::kDirectReasonsForRotateProperty |
CompositingReason::kDirectReasonsForScaleProperty))
return true;
return !object.LocalToSVGParentTransform().IsIdentity();
}
static void SetTransformNodeStateFromAffineTransform(
TransformPaintPropertyNode::State& state,
const AffineTransform& transform) {
if (transform.IsIdentityOrTranslation())
state.transform_and_origin = {gfx::Vector2dF(transform.E(), transform.F())};
else
state.transform_and_origin = {TransformationMatrix(transform)};
}
void FragmentPaintPropertyTreeBuilder::SetTransformNodeStateForSVGChild(
TransformPaintPropertyNode::State& state) {
if (full_context_.direct_compositing_reasons &
CompositingReason::kActiveTransformAnimation) {
if (CompositorAnimations::CanStartTransformAnimationOnCompositorForSVG(
*To<SVGElement>(object_.GetNode()))) {
// For composited transform animation to work, we need to store transform
// origin separately. It's baked in object_.LocalToSVGParentTransform().
state.transform_and_origin = {
TransformationMatrix(TransformHelper::ComputeTransform(
object_, ComputedStyle::kExcludeTransformOrigin)),
gfx::Point3F(TransformHelper::ComputeTransformOrigin(object_))};
// Composited transform animation works only if
// LocalToSVGParentTransform() reflects the CSS transform properties.
// If this fails, we need to exclude the case in
// CompositorAnimations::CanStartTransformAnimationOnCompositorForSVG().
DCHECK_EQ(TransformHelper::ComputeTransform(
object_, ComputedStyle::kIncludeTransformOrigin),
object_.LocalToSVGParentTransform());
} else {
// We composite the object but can't start composited animation. Still
// keep the compositing reason because it still improves performance of
// main thread animation, but avoid the 2d translation optimization to
// meet the requirement of TransformPaintPropertyNode.
state.transform_and_origin = {
TransformationMatrix(object_.LocalToSVGParentTransform())};
}
} else {
SetTransformNodeStateFromAffineTransform(
state, object_.LocalToSVGParentTransform());
}
}
// SVG does not use the general transform update of |UpdateTransform|, instead
// creating a transform node for SVG-specific transforms without 3D.
// TODO(crbug.com/1278452): Merge SVG handling into the primary codepath.
void FragmentPaintPropertyTreeBuilder::UpdateTransformForSVGChild(
CompositingReasons direct_compositing_reasons) {
DCHECK(properties_);
DCHECK(object_.IsSVGChild());
// SVG does not use paint offset internally, except for SVGForeignObject which
// has different SVG and HTML coordinate spaces.
DCHECK(object_.IsSVGForeignObjectIncludingNG() ||
context_.current.paint_offset.IsZero());
if (NeedsPaintPropertyUpdate()) {
if (NeedsTransformForSVGChild(object_, direct_compositing_reasons)) {
// The origin is included in the local transform, so leave origin empty.
TransformPaintPropertyNode::State state;
SetTransformNodeStateForSVGChild(state);
// TODO(pdr): There is additional logic in
// FragmentPaintPropertyTreeBuilder::UpdateTransform that likely needs to
// be included here, such as setting animation_is_axis_aligned.
state.direct_compositing_reasons =
direct_compositing_reasons & CompositingReasonsForTransformProperty();
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
state.rendering_context_id = context_.rendering_context_id;
state.flags.is_for_svg_child = true;
state.compositor_element_id = GetCompositorElementId(
CompositorElementIdNamespace::kPrimaryTransform);
TransformPaintPropertyNode::AnimationState animation_state;
animation_state.is_running_animation_on_compositor =
object_.StyleRef().IsRunningTransformAnimationOnCompositor();
auto effective_change_type = properties_->UpdateTransform(
*context_.current.transform, std::move(state), animation_state);
// We only assume worst-case overlap testing due to animations (see:
// |PendingLayer::VisualRectForOverlapTesting|) so we can only use the
// direct transform update (which skips checking for compositing changes)
// when animations are present.
if (effective_change_type ==
PaintPropertyChangeType::kChangedOnlySimpleValues &&
properties_->Transform()->HasActiveTransformAnimation()) {
if (auto* paint_artifact_compositor =
object_.GetFrameView()->GetPaintArtifactCompositor()) {
bool updated = paint_artifact_compositor->DirectlyUpdateTransform(
*properties_->Transform());
if (updated) {
effective_change_type =
PaintPropertyChangeType::kChangedOnlyCompositedValues;
properties_->Transform()->CompositorSimpleValuesUpdated();
}
}
}
OnUpdateTransform(effective_change_type);
} else {
OnClearTransform(properties_->ClearTransform());
}
}
if (properties_->Transform()) {
context_.current.transform = properties_->Transform();
context_.should_flatten_inherited_transform = true;
context_.rendering_context_id = 0;
}
}
static gfx::Point3F TransformOrigin(const LayoutBox& box, PhysicalSize size) {
// Transform origin has no effect without a transform or motion path.
if (!box.HasTransform())
return gfx::Point3F();
gfx::SizeF border_box_size(size);
const auto& style = box.StyleRef();
return gfx::Point3F(
FloatValueForLength(style.TransformOriginX(), border_box_size.width()),
FloatValueForLength(style.TransformOriginY(), border_box_size.height()),
style.TransformOriginZ());
}
static bool NeedsIndividualTransform(
const LayoutObject& object,
CompositingReasons relevant_compositing_reasons,
bool (*style_test)(const ComputedStyle&)) {
if (object.IsText() || object.IsSVGChild())
return false;
if (relevant_compositing_reasons)
return true;
if (!object.IsBox())
return false;
if (style_test(object.StyleRef()))
return true;
return false;
}
static bool NeedsTranslate(const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
return NeedsIndividualTransform(
object,
direct_compositing_reasons &
CompositingReason::kDirectReasonsForTranslateProperty,
[](const ComputedStyle& style) {
return style.Translate() || style.HasCurrentTranslateAnimation();
});
}
static bool NeedsRotate(const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
return NeedsIndividualTransform(
object,
direct_compositing_reasons &
CompositingReason::kDirectReasonsForRotateProperty,
[](const ComputedStyle& style) {
return style.Rotate() || style.HasCurrentRotateAnimation();
});
}
static bool NeedsScale(const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
return NeedsIndividualTransform(
object,
direct_compositing_reasons &
CompositingReason::kDirectReasonsForScaleProperty,
[](const ComputedStyle& style) {
return style.Scale() || style.HasCurrentScaleAnimation();
});
}
static bool NeedsOffset(const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
return NeedsIndividualTransform(
object, CompositingReason::kNone,
[](const ComputedStyle& style) { return style.HasOffset(); });
}
static bool NeedsTransform(const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
if (object.IsText() || object.IsSVGChild())
return false;
if (object.StyleRef().BackfaceVisibility() == EBackfaceVisibility::kHidden)
return true;
if (direct_compositing_reasons & CompositingReasonsForTransformProperty())
return true;
if (!object.IsBox())
return false;
if (object.StyleRef().HasTransformOperations() ||
object.StyleRef().HasCurrentTransformAnimation() ||
object.StyleRef().Preserves3D())
return true;
return false;
}
static bool UpdateBoxSizeAndCheckActiveAnimationAxisAlignment(
const LayoutBox& object,
CompositingReasons compositing_reasons) {
if (!(compositing_reasons & (CompositingReason::kActiveTransformAnimation |
CompositingReason::kActiveScaleAnimation |
CompositingReason::kActiveRotateAnimation |
CompositingReason::kActiveTranslateAnimation)))
return false;
if (!object.GetNode() || !object.GetNode()->IsElementNode())
return false;
const Element* element = To<Element>(object.GetNode());
auto* animations = element->GetElementAnimations();
DCHECK(animations);
return animations->UpdateBoxSizeAndCheckTransformAxisAlignment(
gfx::SizeF(object.Size()));
}
void FragmentPaintPropertyTreeBuilder::UpdateIndividualTransform(
bool (*needs_property)(const LayoutObject&, CompositingReasons),
void (*compute_matrix)(const ComputedStyle& style,
const PhysicalSize& size,
TransformationMatrix& matrix),
CompositingReasons active_animation_reason,
CompositingReasons compositing_reasons_for_property,
CompositorElementIdNamespace compositor_namespace,
bool (ComputedStyle::*running_on_compositor_test)() const,
const TransformPaintPropertyNode* (ObjectPaintProperties::*getter)() const,
PaintPropertyChangeType (ObjectPaintProperties::*updater)(
const TransformPaintPropertyNodeOrAlias&,
TransformPaintPropertyNode::State&&,
const TransformPaintPropertyNode::AnimationState&),
bool (ObjectPaintProperties::*clearer)()) {
// TODO(crbug.com/1278452): Merge SVG handling into the primary
// codepath (which is this one).
DCHECK(!object_.IsSVGChild());
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
const ComputedStyle& style = object_.StyleRef();
// A transform node is allocated for transforms, preserves-3d and any
// direct compositing reason. The latter is required because this is the
// only way to represent compositing both an element and its stacking
// descendants.
if ((*needs_property)(object_, full_context_.direct_compositing_reasons)) {
TransformPaintPropertyNode::State state;
// A few pieces of the code are only for the 'transform' property
// and not for the others.
bool handling_transform_property =
compositor_namespace ==
CompositorElementIdNamespace::kPrimaryTransform;
if (object_.IsBox()) {
auto& box = To<LayoutBox>(object_);
// Each individual fragment should have its own transform origin, based
// on the fragment size.
PhysicalSize size;
if (!pre_paint_info_)
size = PhysicalSize(box.Size());
else
size = pre_paint_info_->box_fragment.Size();
TransformationMatrix matrix;
compute_matrix(style, size, matrix);
// If we are running transform animation on compositor, we should
// disable 2d translation optimization to ensure that the compositor
// gets the correct origin (which might be omitted by the optimization)
// to the compositor, in case later animated values will use the origin.
// See http://crbug.com/937929 for why we are not using
// style.IsRunningTransformAnimationOnCompositor() etc. here.
bool disable_2d_translation_optimization =
full_context_.direct_compositing_reasons & active_animation_reason;
if (!disable_2d_translation_optimization &&
matrix.IsIdentityOr2DTranslation()) {
state.transform_and_origin = {matrix.To2DTranslation()};
} else {
state.transform_and_origin = {matrix, TransformOrigin(box, size)};
}
// We want to track whether (a) this element is in a preserve-3d scene
// and (b) has a matrix that puts it into the third dimension in some
// way. The test we use for (b) is stricter than
// !matrix.Is2dTransform() or !matrix.IsFlat(); we're interested
// *only* in things that cause this element to have a nonzero z
// position within the 3-D scene.
if (context_.rendering_context_id &&
(matrix.M13() != 0.0 || matrix.M23() != 0.0 ||
matrix.M43() != 0.0)) {
UseCounter::Count(object_.GetDocument(),
WebFeature::kTransform3dScene);
}
// TODO(trchen): transform-style should only be respected if a
// PaintLayer is created. If a node with transform-style: preserve-3d
// does not exist in an existing rendering context, it establishes a
// new one.
state.rendering_context_id = context_.rendering_context_id;
if (handling_transform_property && style.Preserves3D() &&
!state.rendering_context_id) {
state.rendering_context_id =
PtrHash<const LayoutObject>::GetHash(&object_);
}
// TODO(crbug.com/1185254): Make this work correctly for block
// fragmentation. It's the size of each individual NGPhysicalBoxFragment
// that's interesting, not the total LayoutBox size.
state.flags.animation_is_axis_aligned =
UpdateBoxSizeAndCheckActiveAnimationAxisAlignment(
box, full_context_.direct_compositing_reasons);
}
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
compositing_reasons_for_property;
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
if (running_on_compositor_test) {
state.compositor_element_id =
GetCompositorElementId(compositor_namespace);
}
if (handling_transform_property) {
if (object_.HasHiddenBackface()) {
state.backface_visibility =
TransformPaintPropertyNode::BackfaceVisibility::kHidden;
} else if (state.direct_compositing_reasons !=
CompositingReason::kNone) {
// The above condition fixes a CompositeAfterPaint regression
// (crbug.com/1260603) by letting non-directly-composited transforms
// inherit parent's backface visibility.
// TODO(crbug.com/1261905): Fix the the root cause, and revisit the
// above condition and make it at least more web developer friendly.
state.backface_visibility =
TransformPaintPropertyNode::BackfaceVisibility::kVisible;
}
}
TransformPaintPropertyNode::AnimationState animation_state;
animation_state.is_running_animation_on_compositor =
running_on_compositor_test && (style.*running_on_compositor_test)();
auto effective_change_type = (properties_->*updater)(
*context_.current.transform, std::move(state), animation_state);
// We only assume worst-case overlap testing due to animations (see:
// |PendingLayer::VisualRectForOverlapTesting|) so we can only use the
// direct transform update (which skips checking for compositing changes)
// when animations are present.
const auto* transform = (properties_->*getter)();
if (effective_change_type ==
PaintPropertyChangeType::kChangedOnlySimpleValues &&
transform->HasActiveTransformAnimation()) {
if (auto* paint_artifact_compositor =
object_.GetFrameView()->GetPaintArtifactCompositor()) {
bool updated =
paint_artifact_compositor->DirectlyUpdateTransform(*transform);
if (updated) {
effective_change_type =
PaintPropertyChangeType::kChangedOnlyCompositedValues;
transform->CompositorSimpleValuesUpdated();
}
}
}
OnUpdateTransform(effective_change_type);
} else {
OnClearTransform((properties_->*clearer)());
}
}
if (const auto* transform = (properties_->*getter)()) {
context_.current.transform = transform;
if (!transform->IsIdentityOr2DTranslation() &&
!transform->Matrix().Is2dTransform()) {
// We need to not flatten from this node through to this element's
// transform node. (If this is the transform node, we'll undo
// this in the caller.)
context_.should_flatten_inherited_transform = false;
}
if (transform->IsIdentityOr2DTranslation()) {
context_.translation_2d_to_layout_shift_root_delta +=
transform->Translation2D();
}
}
}
void FragmentPaintPropertyTreeBuilder::UpdateTranslate() {
UpdateIndividualTransform(
&NeedsTranslate,
[](const ComputedStyle& style, const PhysicalSize& size,
TransformationMatrix& matrix) {
if (style.Translate())
style.Translate()->Apply(matrix, gfx::SizeF(size));
},
CompositingReason::kActiveTranslateAnimation,
CompositingReason::kDirectReasonsForTranslateProperty,
CompositorElementIdNamespace::kTranslateTransform,
&ComputedStyle::IsRunningTranslateAnimationOnCompositor,
&ObjectPaintProperties::Translate,
&ObjectPaintProperties::UpdateTranslate,
&ObjectPaintProperties::ClearTranslate);
}
void FragmentPaintPropertyTreeBuilder::UpdateRotate() {
UpdateIndividualTransform(
&NeedsRotate,
[](const ComputedStyle& style, const PhysicalSize& size,
TransformationMatrix& matrix) {
if (style.Rotate())
style.Rotate()->Apply(matrix, gfx::SizeF(size));
},
CompositingReason::kActiveRotateAnimation,
CompositingReason::kDirectReasonsForRotateProperty,
CompositorElementIdNamespace::kRotateTransform,
&ComputedStyle::IsRunningRotateAnimationOnCompositor,
&ObjectPaintProperties::Rotate, &ObjectPaintProperties::UpdateRotate,
&ObjectPaintProperties::ClearRotate);
}
void FragmentPaintPropertyTreeBuilder::UpdateScale() {
UpdateIndividualTransform(
&NeedsScale,
[](const ComputedStyle& style, const PhysicalSize& size,
TransformationMatrix& matrix) {
if (style.Scale())
style.Scale()->Apply(matrix, gfx::SizeF(size));
},
CompositingReason::kActiveScaleAnimation,
CompositingReason::kDirectReasonsForScaleProperty,
CompositorElementIdNamespace::kScaleTransform,
&ComputedStyle::IsRunningScaleAnimationOnCompositor,
&ObjectPaintProperties::Scale, &ObjectPaintProperties::UpdateScale,
&ObjectPaintProperties::ClearScale);
}
void FragmentPaintPropertyTreeBuilder::UpdateOffset() {
UpdateIndividualTransform(
&NeedsOffset,
[](const ComputedStyle& style, const PhysicalSize& size,
TransformationMatrix& matrix) {
style.ApplyTransform(
matrix, size.ToLayoutSize(),
ComputedStyle::kExcludeTransformOperations,
ComputedStyle::kExcludeTransformOrigin,
ComputedStyle::kIncludeMotionPath,
ComputedStyle::kExcludeIndependentTransformProperties);
},
CompositingReason::kNone, CompositingReason::kNone,
// TODO(dbaron): When we support animating offset on the
// compositor, we need to use an element ID specific to offset.
// This is currently unused.
CompositorElementIdNamespace::kPrimary, nullptr,
&ObjectPaintProperties::Offset, &ObjectPaintProperties::UpdateOffset,
&ObjectPaintProperties::ClearOffset);
}
void FragmentPaintPropertyTreeBuilder::UpdateTransform() {
UpdateIndividualTransform(
&NeedsTransform,
[](const ComputedStyle& style, const PhysicalSize& size,
TransformationMatrix& matrix) {
style.ApplyTransform(
matrix, size.ToLayoutSize(),
ComputedStyle::kIncludeTransformOperations,
ComputedStyle::kExcludeTransformOrigin,
ComputedStyle::kExcludeMotionPath,
ComputedStyle::kExcludeIndependentTransformProperties);
},
CompositingReason::kActiveTransformAnimation,
CompositingReasonsForTransformProperty(),
CompositorElementIdNamespace::kPrimaryTransform,
&ComputedStyle::IsRunningTransformAnimationOnCompositor,
&ObjectPaintProperties::Transform,
&ObjectPaintProperties::UpdateTransform,
&ObjectPaintProperties::ClearTransform);
// properties_->Transform() is present if a CSS transform is present,
// and is also present if transform-style: preserve-3d is set.
// See NeedsTransform.
if (const auto* transform = properties_->Transform()) {
context_.current.transform = transform;
if (object_.StyleRef().Preserves3D()) {
context_.rendering_context_id = transform->RenderingContextId();
context_.should_flatten_inherited_transform = false;
} else {
context_.rendering_context_id = 0;
context_.should_flatten_inherited_transform = true;
}
} else if (object_.IsForElement()) {
// 3D rendering contexts follow the DOM ancestor chain, so
// flattening should apply regardless of presence of transform.
context_.rendering_context_id = 0;
context_.should_flatten_inherited_transform = true;
}
}
static bool NeedsClipPathClipOrMask(const LayoutObject& object) {
// We only apply clip-path if the LayoutObject has a layer or is an SVG
// child. See NeedsEffect() for additional information on the former.
return !object.IsText() && object.StyleRef().HasClipPath() &&
(object.HasLayer() || object.IsSVGChild());
}
static bool NeedsEffectIgnoringClipPath(
const LayoutObject& object,
CompositingReasons direct_compositing_reasons) {
if (object.IsText()) {
DCHECK(!(direct_compositing_reasons &
CompositingReason::kDirectReasonsForEffectProperty));
return false;
}
if (direct_compositing_reasons &
CompositingReason::kDirectReasonsForEffectProperty)
return true;
const ComputedStyle& style = object.StyleRef();
// For now some objects (e.g. LayoutTableCol) with stacking context style
// don't create layer thus are not actual stacking contexts, so the HasLayer()
// condition. TODO(crbug.com/892734): Support effects for LayoutTableCol.
const bool is_css_isolated_group =
object.HasLayer() && object.IsStackingContext();
if (!is_css_isolated_group && !object.IsSVG())
return false;
if (object.IsSVG() && SVGLayoutSupport::IsIsolationRequired(&object))
return true;
if (is_css_isolated_group) {
const auto* layer = To<LayoutBoxModelObject>(object).Layer();
DCHECK(layer);
if (layer->HasNonIsolatedDescendantWithBlendMode())
return true;
}
if (object.IsBlendingAllowed() &&
WebCoreCompositeToSkiaComposite(
kCompositeSourceOver, style.GetBlendMode()) != SkBlendMode::kSrcOver)
return true;
if (!style.BackdropFilter().IsEmpty())
return true;
if (style.Opacity() != 1.0f)
return true;
// A mask needs an effect node on the current LayoutObject to define the scope
// of masked contents to be the current LayoutObject and its descendants.
if (object.StyleRef().HasMask())
return true;
return false;
}
bool FragmentPaintPropertyTreeBuilder::NeedsEffect() const {
DCHECK(NeedsPaintPropertyUpdate());
// A mask-based clip-path needs an effect node, similar to a normal mask.
if (needs_mask_based_clip_path_)
return true;
return NeedsEffectIgnoringClipPath(object_,
full_context_.direct_compositing_reasons);
}
// An effect node can use the current clip as its output clip if the clip won't
// end before the effect ends. Having explicit output clip can let the later
// stages use more optimized code path.
bool FragmentPaintPropertyTreeBuilder::EffectCanUseCurrentClipAsOutputClip()
const {
DCHECK(NeedsEffect());
if (!object_.HasLayer()) {
// This is either SVG or it's the effect node to create flattening at the
// leaves of a 3D scene.
//
// Either way, the effect never interleaves with clips, because
// positioning is the only situation where clip order changes.
return true;
}
const auto* layer = To<LayoutBoxModelObject>(object_).Layer();
// Out-of-flow descendants not contained by this object may escape clips.
if (layer->HasNonContainedAbsolutePositionDescendant() &&
&object_.ContainerForAbsolutePosition()->FirstFragment().ContentsClip() !=
context_.current.clip)
return false;
if (layer->HasFixedPositionDescendant() &&
!object_.CanContainFixedPositionObjects() &&
&object_.ContainerForFixedPosition()->FirstFragment().ContentsClip() !=
context_.current.clip)
return false;
// Some descendants under a pagination container (e.g. composited objects
// in SPv1 and column spanners) may escape fragment clips.
// TODO(crbug.com/803649): Remove this when we fix fragment clip hierarchy
// issues.
if (layer->EnclosingPaginationLayer())
return false;
return true;
}
void FragmentPaintPropertyTreeBuilder::UpdateEffect() {
DCHECK(properties_);
const ComputedStyle& style = object_.StyleRef();
if (NeedsPaintPropertyUpdate()) {
if (NeedsEffect()) {
absl::optional<gfx::RectF> mask_clip = CSSMaskPainter::MaskBoundingBox(
object_, context_.current.paint_offset);
if (mask_clip || needs_mask_based_clip_path_) {
DCHECK(mask_clip || clip_path_bounding_box_.has_value());
gfx::RectF combined_clip =
mask_clip ? *mask_clip : *clip_path_bounding_box_;
if (mask_clip && needs_mask_based_clip_path_)
combined_clip.Intersect(*clip_path_bounding_box_);
OnUpdateClip(properties_->UpdateMaskClip(
*context_.current.clip,
ClipPaintPropertyNode::State(
context_.current.transform, combined_clip,
FloatRoundedRect(gfx::ToEnclosingRect(combined_clip)))));
// We don't use MaskClip as the output clip of Effect, Mask and
// ClipPathMask because we only want to apply MaskClip to the contents,
// not the masks.
} else {
OnClearClip(properties_->ClearMaskClip());
}
CompositorElementId mask_compositor_element_id;
if (mask_clip) {
mask_compositor_element_id =
GetCompositorElementId(CompositorElementIdNamespace::kEffectMask);
}
EffectPaintPropertyNode::State state;
state.local_transform_space = context_.current.transform;
if (EffectCanUseCurrentClipAsOutputClip())
state.output_clip = context_.current.clip;
state.opacity = style.Opacity();
if (object_.IsBlendingAllowed()) {
state.blend_mode = WebCoreCompositeToSkiaComposite(
kCompositeSourceOver, style.GetBlendMode());
}
if (object_.IsBoxModelObject()) {
if (auto* layer = To<LayoutBoxModelObject>(object_).Layer()) {
CompositorFilterOperations operations;
gfx::RRectF bounds;
// Try to use the cached effect for backdrop-filter.
if (properties_->Effect() &&
properties_->Effect()->BackdropFilter()) {
operations = *properties_->Effect()->BackdropFilter();
bounds = properties_->Effect()->BackdropFilterBounds();
}
layer->UpdateCompositorFilterOperationsForBackdropFilter(operations,
bounds);
if (!operations.IsEmpty()) {
state.backdrop_filter_info = base::WrapUnique(
new EffectPaintPropertyNode::BackdropFilterInfo{
std::move(operations), bounds, mask_compositor_element_id});
}
}
}
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kDirectReasonsForEffectProperty;
// If an effect node exists, add an additional direct compositing reason
// for 3d transforms and will-change:transform to ensure it is composited.
state.direct_compositing_reasons |=
(full_context_.direct_compositing_reasons &
CompositingReason::kAdditionalEffectCompositingTrigger);
// We may begin to composite our subtree prior to an animation starts, but
// a compositor element ID is only needed when an animation is current.
// Currently, we use the existence of this id to check if effect nodes
// have been created for animations on this element.
if (state.direct_compositing_reasons) {
state.compositor_element_id = GetCompositorElementId(
CompositorElementIdNamespace::kPrimaryEffect);
} else {
// The effect node CompositorElementId is used to uniquely identify
// renderpasses so even if we don't need one for animations we still
// need to set an id. Using kPrimary avoids confusing cc::Animation
// into thinking the element has been composited for animations.
state.compositor_element_id =
GetCompositorElementId(CompositorElementIdNamespace::kPrimary);
}
EffectPaintPropertyNode::AnimationState animation_state;
animation_state.is_running_opacity_animation_on_compositor =
style.IsRunningOpacityAnimationOnCompositor();
animation_state.is_running_backdrop_filter_animation_on_compositor =
style.IsRunningBackdropFilterAnimationOnCompositor();
auto* parent_effect = context_.current_effect;
// The transition pseudo element doesn't draw into the LayoutView's
// effect, but rather as its sibling. So this re-parents the effect to
// whatever the grand-parent effect was. Note that it doesn't matter
// whether the grand-parent is the root stacking context or something
// intermediate, as long as it is a sibling of the LayoutView context.
// This makes it possible to capture the output of the LayoutView context
// into one of the transition contexts. We also want that capture to be
// without any additional effects, such as overscroll elasticity effects.
if (object_.GetNode() &&
object_.GetNode()->GetPseudoId() == kPseudoIdPageTransition) {
parent_effect = context_.current_effect->Parent();
}
DCHECK(parent_effect);
auto effective_change_type = properties_->UpdateEffect(
*parent_effect, std::move(state), animation_state);
// If we have simple value change, which means opacity, we should try to
// directly update it on the PaintArtifactCompositor in order to avoid
// doing a full rebuild.
if (effective_change_type ==
PaintPropertyChangeType::kChangedOnlySimpleValues &&
properties_->Effect()->HasDirectCompositingReasons() &&
// TODO(crbug.com/1253797): Due to the bug, we may create multiple
// cc effect nodes for one blink effect node of a fragmented object,
// and direct update would be incomplete in the case.
!object_.FirstFragment().NextFragment()) {
if (auto* paint_artifact_compositor =
object_.GetFrameView()->GetPaintArtifactCompositor()) {
bool updated =
paint_artifact_compositor->DirectlyUpdateCompositedOpacityValue(
*properties_->Effect());
if (updated) {
effective_change_type =
PaintPropertyChangeType::kChangedOnlyCompositedValues;
properties_->Effect()->CompositorSimpleValuesUpdated();
}
}
}
OnUpdateEffect(effective_change_type);
auto mask_direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kDirectReasonsForBackdropFilter
? CompositingReason::kBackdropFilterMask
: CompositingReason::kNone;
if (mask_clip) {
EffectPaintPropertyNode::State mask_state;
mask_state.local_transform_space = context_.current.transform;
mask_state.output_clip = context_.current.clip;
mask_state.blend_mode = SkBlendMode::kDstIn;
mask_state.compositor_element_id = mask_compositor_element_id;
mask_state.direct_compositing_reasons = mask_direct_compositing_reasons;
OnUpdateEffect(properties_->UpdateMask(*properties_->Effect(),
std::move(mask_state)));
} else {
OnClearEffect(properties_->ClearMask());
}
if (needs_mask_based_clip_path_) {
EffectPaintPropertyNode::State clip_path_state;
clip_path_state.local_transform_space = context_.current.transform;
clip_path_state.output_clip = context_.current.clip;
clip_path_state.blend_mode = SkBlendMode::kDstIn;
clip_path_state.compositor_element_id = GetCompositorElementId(
CompositorElementIdNamespace::kEffectClipPath);
if (!mask_clip) {
clip_path_state.direct_compositing_reasons =
mask_direct_compositing_reasons;
}
OnUpdateEffect(properties_->UpdateClipPathMask(
properties_->Mask() ? *properties_->Mask() : *properties_->Effect(),
std::move(clip_path_state)));
} else {
OnClearEffect(properties_->ClearClipPathMask());
}
} else {
OnClearEffect(properties_->ClearEffect());
OnClearEffect(properties_->ClearMask());
OnClearEffect(properties_->ClearClipPathMask());
OnClearClip(properties_->ClearMaskClip());
}
}
if (const auto* effect = properties_->Effect()) {
context_.current_effect = effect;
context_.this_or_ancestor_opacity_is_zero |= effect->Opacity() == 0;
if (properties_->MaskClip()) {
context_.current.clip = context_.absolute_position.clip =
context_.fixed_position.clip = properties_->MaskClip();
}
}
}
void FragmentPaintPropertyTreeBuilder::UpdateSharedElementTransitionEffect() {
if (NeedsPaintPropertyUpdate()) {
if (full_context_.direct_compositing_reasons &
CompositingReason::kDocumentTransitionSharedElement) {
auto* supplement =
DocumentTransitionSupplement::FromIfExists(object_.GetDocument());
DCHECK(supplement);
OnUpdateEffect(supplement->GetTransition()->UpdateEffect(
object_, *context_.current_effect, context_.current.clip,
context_.current.transform));
context_.current_effect = supplement->GetTransition()->GetEffect(object_);
}
}
}
static bool IsLinkHighlighted(const LayoutObject& object) {
return object.GetFrame()->GetPage()->GetLinkHighlight().IsHighlighting(
object);
}
static bool IsClipPathDescendant(const LayoutObject& object) {
// If the object itself is a resource container (root of a resource subtree)
// it is not considered a clipPath descendant since it is independent of its
// ancestors.
if (object.IsSVGResourceContainer())
return false;
const LayoutObject* parent = object.Parent();
while (parent) {
if (parent->IsSVGResourceContainer()) {
auto* container = To<LayoutSVGResourceContainer>(parent);
return container->ResourceType() == kClipperResourceType;
}
parent = parent->Parent();
}
return false;
}
static bool NeedsFilter(const LayoutObject& object,
const PaintPropertyTreeBuilderContext& full_context) {
if (full_context.direct_compositing_reasons &
CompositingReason::kDirectReasonsForFilterProperty)
return true;
if (object.IsBoxModelObject() &&
To<LayoutBoxModelObject>(object).HasLayer()) {
if (object.StyleRef().HasFilter() || object.HasReflection())
return true;
} else if (object.IsSVGChild() && !object.IsText() &&
SVGResources::GetClient(object)) {
if (object.StyleRef().HasFilter()) {
// Filters don't apply to elements that are descendants of a <clipPath>.
if (!full_context.has_svg_hidden_container_ancestor ||
!IsClipPathDescendant(object))
return true;
}
}
return false;
}
static void UpdateFilterEffect(const LayoutObject& object,
const EffectPaintPropertyNode* effect_node,
CompositorFilterOperations& filter) {
if (object.HasLayer()) {
// Try to use the cached filter.
if (effect_node)
filter = effect_node->Filter();
PaintLayer* layer = To<LayoutBoxModelObject>(object).Layer();
#if DCHECK_IS_ON()
// We should have already updated the reference box.
auto reference_box = layer->FilterReferenceBox();
layer->UpdateFilterReferenceBox();
DCHECK_EQ(reference_box, layer->FilterReferenceBox());
#endif
layer->UpdateCompositorFilterOperationsForFilter(filter);
return;
}
if (object.IsSVGChild() && !object.IsText()) {
SVGElementResourceClient* client = SVGResources::GetClient(object);
if (!client)
return;
if (!object.StyleRef().HasFilter())
return;
// Try to use the cached filter.
if (effect_node)
filter = effect_node->Filter();
client->UpdateFilterData(filter);
}
}
void FragmentPaintPropertyTreeBuilder::UpdateFilter() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsFilter(object_, full_context_)) {
EffectPaintPropertyNode::State state;
state.local_transform_space = context_.current.transform;
UpdateFilterEffect(object_, properties_->Filter(), state.filter);
// The CSS filter spec didn't specify how filters interact with overflow
// clips. The implementation here mimics the old Blink/WebKit behavior for
// backward compatibility.
// Basically the output of the filter will be affected by clips that
// applies to the current element. The descendants that paints into the
// input of the filter ignores any clips collected so far. For example:
// <div style="overflow:scroll">
// <div style="filter:blur(1px);">
// <div>A</div>
// <div style="position:absolute;">B</div>
// </div>
// </div>
// In this example "A" should be clipped if the filter was not present.
// With the filter, "A" will be rastered without clipping, but instead
// the blurred result will be clipped.
// "B" should be also clipped because a filter always creates a containing
// block for all descendants.
if (!state.filter.IsEmpty() ||
(full_context_.direct_compositing_reasons &
CompositingReason::kActiveFilterAnimation))
state.output_clip = context_.current.clip;
// We may begin to composite our subtree prior to an animation starts,
// but a compositor element ID is only needed when an animation is
// current.
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kDirectReasonsForFilterProperty;
// If a filter node exists, add an additional direct compositing reason
// for 3d transforms and will-change:transform to ensure it is composited.
state.direct_compositing_reasons |=
(full_context_.direct_compositing_reasons &
CompositingReason::kAdditionalEffectCompositingTrigger);
state.compositor_element_id =
GetCompositorElementId(CompositorElementIdNamespace::kEffectFilter);
// This must be computed before std::move(state) below.
bool needs_pixel_moving_filter_clip_expander =
(state.direct_compositing_reasons &
(CompositingReason::kWillChangeFilter |
CompositingReason::kActiveFilterAnimation)) ||
state.filter.HasFilterThatMovesPixels();
EffectPaintPropertyNode::AnimationState animation_state;
animation_state.is_running_filter_animation_on_compositor =
object_.StyleRef().IsRunningFilterAnimationOnCompositor();
OnUpdateEffect(properties_->UpdateFilter(
*context_.current_effect, std::move(state), animation_state));
if (needs_pixel_moving_filter_clip_expander) {
OnUpdateClip(properties_->UpdatePixelMovingFilterClipExpander(
*context_.current.clip,
ClipPaintPropertyNode::State(context_.current.transform,
*properties_->Filter())));
} else {
OnClearClip(properties_->ClearPixelMovingFilterClipExpander());
}
} else {
OnClearEffect(properties_->ClearFilter());
OnClearClip(properties_->ClearPixelMovingFilterClipExpander());
}
}
if (properties_->Filter()) {
context_.current_effect = properties_->Filter();
if (const auto* input_clip = properties_->PixelMovingFilterClipExpander())
context_.current.clip = input_clip;
} else {
DCHECK(!properties_->PixelMovingFilterClipExpander());
}
}
static FloatRoundedRect ToSnappedClipRect(const PhysicalRect& rect) {
return FloatRoundedRect(ToPixelSnappedRect(rect));
}
void FragmentPaintPropertyTreeBuilder::UpdateFragmentClip() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (context_.fragment_clip) {
const auto& clip_rect = *context_.fragment_clip;
OnUpdateClip(properties_->UpdateFragmentClip(
*context_.current.clip,
ClipPaintPropertyNode::State(context_.current.transform,
gfx::RectF(clip_rect),
ToSnappedClipRect(clip_rect))));
} else {
OnClearClip(properties_->ClearFragmentClip());
}
}
if (properties_->FragmentClip())
context_.current.clip = properties_->FragmentClip();
}
static bool NeedsCssClip(const LayoutObject& object) {
if (object.HasClip()) {
DCHECK(!object.IsText());
return true;
}
return false;
}
void FragmentPaintPropertyTreeBuilder::UpdateCssClip() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsCssClip(object_)) {
// Create clip node for descendants that are not fixed position.
// We don't have to setup context.absolutePosition.clip here because this
// object must be a container for absolute position descendants, and will
// copy from in-flow context later at updateOutOfFlowContext() step.
DCHECK(object_.CanContainAbsolutePositionObjects());
const auto& clip_rect =
To<LayoutBox>(object_).ClipRect(context_.current.paint_offset);
OnUpdateClip(properties_->UpdateCssClip(
*context_.current.clip,
ClipPaintPropertyNode::State(context_.current.transform,
gfx::RectF(clip_rect),
ToSnappedClipRect(clip_rect))));
} else {
OnClearClip(properties_->ClearCssClip());
}
}
if (properties_->CssClip())
context_.current.clip = properties_->CssClip();
}
void FragmentPaintPropertyTreeBuilder::UpdateClipPathClip() {
if (NeedsPaintPropertyUpdate()) {
DCHECK(!clip_path_bounding_box_.has_value());
if (NeedsClipPathClipOrMask(object_)) {
clip_path_bounding_box_ =
ClipPathClipper::LocalClipPathBoundingBox(object_);
if (clip_path_bounding_box_) {
clip_path_bounding_box_->Offset(
gfx::Vector2dF(context_.current.paint_offset));
if (absl::optional<Path> path =
ClipPathClipper::PathBasedClip(object_)) {
path->Translate(gfx::Vector2dF(context_.current.paint_offset));
ClipPaintPropertyNode::State state(
context_.current.transform, *clip_path_bounding_box_,
FloatRoundedRect(gfx::ToEnclosingRect(*clip_path_bounding_box_)));
state.clip_path = path;
OnUpdateClip(properties_->UpdateClipPathClip(*context_.current.clip,
std::move(state)));
} else {
// This means that the clip-path is too complex to be represented as a
// Path. Will create ClipPathMask in UpdateEffect().
needs_mask_based_clip_path_ = true;
}
}
}
if (!clip_path_bounding_box_ || needs_mask_based_clip_path_)
OnClearClip(properties_->ClearClipPathClip());
}
if (properties_->ClipPathClip()) {
context_.current.clip = context_.absolute_position.clip =
context_.fixed_position.clip = properties_->ClipPathClip();
}
}
// The clipping behaviour for replaced elements is defined by overflow,
// overflow-clip-margin and paint containment. See resolution at:
// https://github.com/w3c/csswg-drafts/issues/7144#issuecomment-1090933632
static bool ReplacedElementAlwaysClipsToContentBox(
const LayoutReplaced& replaced) {
return !replaced.RespectsCSSOverflow();
}
// TODO(wangxianzhu): Combine the logic by overriding LayoutBox::
// ComputeOverflowClipAxes() in LayoutReplaced and subclasses and remove
// this function.
static bool NeedsOverflowClipForReplacedContents(
const LayoutReplaced& replaced) {
// <svg> may optionally allow overflow. If an overflow clip is required,
// always create it without checking whether the actual content overflows.
if (replaced.IsSVGRoot())
return To<LayoutSVGRoot>(replaced).ClipsToContentBox();
// A replaced element with border-radius always clips the content.
if (replaced.StyleRef().HasBorderRadius())
return true;
// ImagePainter (but not painters for LayoutMedia whose IsImage is also true)
// won't paint outside of the content box.
if (replaced.IsImage() && !replaced.IsMedia())
return false;
// Non-plugin embedded contents are always sized to fit the content box.
if (replaced.IsLayoutEmbeddedContent() && !replaced.IsEmbeddedObject())
return false;
return true;
}
static bool NeedsOverflowClip(const LayoutObject& object) {
if (const auto* replaced = DynamicTo<LayoutReplaced>(object)) {
if (ReplacedElementAlwaysClipsToContentBox(*replaced))
return NeedsOverflowClipForReplacedContents(*replaced);
}
if (object.IsSVGViewportContainer() &&
SVGLayoutSupport::IsOverflowHidden(object))
return true;
if (!object.IsBox())
return false;
if (!To<LayoutBox>(object).ShouldClipOverflowAlongEitherAxis())
return false;
if (IsA<LayoutView>(object) && !object.GetFrame()->ClipsContent())
return false;
return true;
}
void FragmentPaintPropertyTreeBuilder::UpdateLocalBorderBoxContext() {
if (!NeedsPaintPropertyUpdate())
return;
const TransformPaintPropertyNodeOrAlias* old_transform = nullptr;
const ClipPaintPropertyNodeOrAlias* old_clip = nullptr;
const EffectPaintPropertyNodeOrAlias* old_effect = nullptr;
if (fragment_data_.HasLocalBorderBoxProperties()) {
old_transform = &fragment_data_.LocalBorderBoxProperties().Transform();
old_clip = &fragment_data_.LocalBorderBoxProperties().Clip();
old_effect = &fragment_data_.LocalBorderBoxProperties().Effect();
}
const TransformPaintPropertyNodeOrAlias* new_transform = nullptr;
const ClipPaintPropertyNodeOrAlias* new_clip = nullptr;
const EffectPaintPropertyNodeOrAlias* new_effect = nullptr;
if (object_.HasLayer() || properties_ || IsLinkHighlighted(object_) ||
object_.CanContainFixedPositionObjects() ||
object_.CanContainAbsolutePositionObjects()) {
new_transform = context_.current.transform;
new_clip = context_.current.clip;
new_effect = context_.current_effect;
fragment_data_.SetLocalBorderBoxProperties(
PropertyTreeStateOrAlias(*new_transform, *new_clip, *new_effect));
} else {
fragment_data_.ClearLocalBorderBoxProperties();
}
if (old_transform != new_transform) {
properties_changed_.transform_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
if (old_clip != new_clip) {
properties_changed_.clip_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
if (old_effect != new_effect) {
properties_changed_.effect_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
}
bool FragmentPaintPropertyTreeBuilder::NeedsOverflowControlsClip() const {
if (!object_.IsScrollContainer())
return false;
const auto& box = To<LayoutBox>(object_);
const auto* scrollable_area = box.GetScrollableArea();
gfx::Rect scroll_controls_bounds =
scrollable_area->ScrollCornerAndResizerRect();
if (const auto* scrollbar = scrollable_area->HorizontalScrollbar())
scroll_controls_bounds.Union(scrollbar->FrameRect());
if (const auto* scrollbar = scrollable_area->VerticalScrollbar())
scroll_controls_bounds.Union(scrollbar->FrameRect());
gfx::Rect pixel_snapped_border_box_rect(
gfx::Point(),
box.PixelSnappedBorderBoxSize(context_.current.paint_offset));
return !pixel_snapped_border_box_rect.Contains(scroll_controls_bounds);
}
static bool NeedsInnerBorderRadiusClip(const LayoutObject& object) {
// If a replaced element always clips to its content box then the border
// radius clip is applied by OverflowClip node. So we don't need to create an
// additional clip node for the border radius.
// If the replaced element respects `overflow` property and can have visible
// overflow, we use a separate node for the border-radius. This is consistent
// with other elements which respect `overflow`.
if (object.IsLayoutReplaced() &&
ReplacedElementAlwaysClipsToContentBox(To<LayoutReplaced>(object))) {
return false;
}
return object.StyleRef().HasBorderRadius() && object.IsBox() &&
NeedsOverflowClip(object);
}
static PhysicalOffset VisualOffsetFromPaintOffsetRoot(
const PaintPropertyTreeBuilderFragmentContext& context,
const PaintLayer* child) {
const LayoutObject* paint_offset_root = context.current.paint_offset_root;
PaintLayer* painting_layer = paint_offset_root->PaintingLayer();
PhysicalOffset result = child->VisualOffsetFromAncestor(painting_layer);
if (!paint_offset_root->HasLayer() ||
To<LayoutBoxModelObject>(paint_offset_root)->Layer() != painting_layer) {
result -= paint_offset_root->OffsetFromAncestor(
&painting_layer->GetLayoutObject());
}
// Convert the result into the space of the scrolling contents space.
if (const auto* properties =
paint_offset_root->FirstFragment().PaintProperties()) {
if (const auto* scroll_translation = properties->ScrollTranslation()) {
// VisualOffsetFromAncestor() uses integer-snapped scroll offsets. Do the
// same here, to cancel out the scroll offset correctly.
gfx::Vector2dF scroll_offset = -scroll_translation->Translation2D();
result += PhysicalOffset::FromVector2dFFloor(
gfx::ToFlooredVector2d(scroll_offset));
}
}
return result;
}
void FragmentPaintPropertyTreeBuilder::UpdateOverflowControlsClip() {
DCHECK(properties_);
if (!NeedsPaintPropertyUpdate())
return;
if (NeedsOverflowControlsClip()) {
// Clip overflow controls to the border box rect.
const auto& clip_rect = PhysicalRect(context_.current.paint_offset,
To<LayoutBox>(object_).Size());
OnUpdateClip(properties_->UpdateOverflowControlsClip(
*context_.current.clip,
ClipPaintPropertyNode::State(context_.current.transform,
gfx::RectF(clip_rect),
ToSnappedClipRect(clip_rect))));
} else {
OnClearClip(properties_->ClearOverflowControlsClip());
}
// We don't walk into custom scrollbars in PrePaintTreeWalk because
// LayoutObjects under custom scrollbars don't support paint properties.
}
static void AdjustRoundedClipForOverflowClipMargin(
const LayoutBox& box,
gfx::RectF& layout_clip_rect,
FloatRoundedRect& paint_clip_rect) {
const auto& style = box.StyleRef();
auto overflow_clip_margin = style.OverflowClipMargin();
if (!overflow_clip_margin || !box.ShouldApplyOverflowClipMargin())
return;
// The default rects map to the inner border-radius which is the padding-box.
// First apply a margin for the reference-box.
LayoutRectOutsets outsets;
switch (overflow_clip_margin->GetReferenceBox()) {
case StyleOverflowClipMargin::ReferenceBox::kBorderBox:
outsets = box.BorderBoxOutsets();
break;
case StyleOverflowClipMargin::ReferenceBox::kPaddingBox:
break;
case StyleOverflowClipMargin::ReferenceBox::kContentBox:
outsets = -box.PaddingOutsets();
break;
}
outsets += overflow_clip_margin->GetMargin();
layout_clip_rect.Outset(gfx::OutsetsF(outsets));
paint_clip_rect.OutsetForMarginOrShadow(gfx::OutsetsF(outsets));
}
void FragmentPaintPropertyTreeBuilder::UpdateInnerBorderRadiusClip() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsInnerBorderRadiusClip(object_)) {
const auto& box = To<LayoutBox>(object_);
PhysicalRect box_rect(context_.current.paint_offset, box.Size());
gfx::RectF layout_clip_rect =
RoundedBorderGeometry::RoundedInnerBorder(box.StyleRef(), box_rect)
.Rect();
FloatRoundedRect paint_clip_rect =
RoundedBorderGeometry::PixelSnappedRoundedInnerBorder(box.StyleRef(),
box_rect);
AdjustRoundedClipForOverflowClipMargin(box, layout_clip_rect,
paint_clip_rect);
ClipPaintPropertyNode::State state(context_.current.transform,
layout_clip_rect, paint_clip_rect);
OnUpdateClip(properties_->UpdateInnerBorderRadiusClip(
*context_.current.clip, std::move(state)));
} else {
OnClearClip(properties_->ClearInnerBorderRadiusClip());
}
}
if (auto* border_radius_clip = properties_->InnerBorderRadiusClip())
context_.current.clip = border_radius_clip;
}
void FragmentPaintPropertyTreeBuilder::UpdateOverflowClip() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsOverflowClip(object_)) {
ClipPaintPropertyNode::State state(context_.current.transform,
gfx::RectF(), FloatRoundedRect());
if (object_.IsLayoutReplaced() &&
ReplacedElementAlwaysClipsToContentBox(To<LayoutReplaced>(object_))) {
const auto& replaced = To<LayoutReplaced>(object_);
// Videos need to be pre-snapped so that they line up with the
// display_rect and can enable hardware overlays. Adjust the base rect
// here, before applying padding and corner rounding.
PhysicalRect content_rect(context_.current.paint_offset,
replaced.Size());
if (IsA<LayoutVideo>(replaced)) {
content_rect =
LayoutReplaced::PreSnappedRectForPersistentSizing(content_rect);
}
// LayoutReplaced clips the foreground by rounded content box.
auto clip_rect =
RoundedBorderGeometry::PixelSnappedRoundedBorderWithOutsets(
replaced.StyleRef(), content_rect,
LayoutRectOutsets(
-(replaced.PaddingTop() + replaced.BorderTop()),
-(replaced.PaddingRight() + replaced.BorderRight()),
-(replaced.PaddingBottom() + replaced.BorderBottom()),
-(replaced.PaddingLeft() + replaced.BorderLeft())));
if (replaced.IsLayoutEmbeddedContent()) {
// Embedded objects are always sized to fit the content rect, but they
// could overflow by 1px due to pre-snapping. Adjust clip rect to
// match pre-snapped box as a special case.
clip_rect.SetRect(
gfx::RectF(clip_rect.Rect().origin(),
gfx::SizeF(replaced.ReplacedContentRect().size)));
}
// TODO(crbug.com/1248598): Should we use non-snapped clip rect for
// the first parameter?
state.SetClipRect(clip_rect.Rect(), clip_rect);
} else if (object_.IsBox()) {
PhysicalRect clip_rect;
if (pre_paint_info_) {
clip_rect = pre_paint_info_->box_fragment.OverflowClipRect(
context_.current.paint_offset,
FindPreviousBreakToken(pre_paint_info_->box_fragment));
} else {
clip_rect = To<LayoutBox>(object_).OverflowClipRect(
context_.current.paint_offset);
}
if (object_.IsLayoutReplaced()) {
// TODO(crbug.com/1248598): Should we use non-snapped clip rect for
// the first parameter?
auto snapped_rect = ToSnappedClipRect(clip_rect);
state.SetClipRect(snapped_rect.Rect(), snapped_rect);
} else {
state.SetClipRect(gfx::RectF(clip_rect),
ToSnappedClipRect(clip_rect));
}
state.layout_clip_rect_excluding_overlay_scrollbars =
FloatClipRect(gfx::RectF(To<LayoutBox>(object_).OverflowClipRect(
context_.current.paint_offset,
kExcludeOverlayScrollbarSizeForHitTesting)));
} else {
DCHECK(object_.IsSVGViewportContainer());
const auto& viewport_container =
To<LayoutSVGViewportContainer>(object_);
const auto clip_rect =
viewport_container.LocalToSVGParentTransform().Inverse().MapRect(
viewport_container.Viewport());
// TODO(crbug.com/1248598): Should we use non-snapped clip rect for
// the first parameter?
state.SetClipRect(clip_rect, FloatRoundedRect(clip_rect));
}
OnUpdateClip(properties_->UpdateOverflowClip(*context_.current.clip,
std::move(state)));
} else {
OnClearClip(properties_->ClearOverflowClip());
}
}
if (auto* overflow_clip = properties_->OverflowClip())
context_.current.clip = overflow_clip;
}
static gfx::PointF PerspectiveOrigin(const LayoutBox& box) {
const ComputedStyle& style = box.StyleRef();
// Perspective origin has no effect without perspective.
DCHECK(style.HasPerspective());
return PointForLengthPoint(style.PerspectiveOrigin(), gfx::SizeF(box.Size()));
}
static bool NeedsPerspective(const LayoutObject& object) {
return object.IsBox() && object.StyleRef().HasPerspective();
}
void FragmentPaintPropertyTreeBuilder::UpdatePerspective() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (NeedsPerspective(object_)) {
const ComputedStyle& style = object_.StyleRef();
// The perspective node must not flatten (else nothing will get
// perspective), but it should still extend the rendering context as
// most transform nodes do.
TransformPaintPropertyNode::State state{
TransformPaintPropertyNode::TransformAndOrigin(
TransformationMatrix().ApplyPerspective(style.UsedPerspective()),
gfx::Point3F(PerspectiveOrigin(To<LayoutBox>(object_)) +
gfx::Vector2dF(context_.current.paint_offset)))};
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
state.rendering_context_id = context_.rendering_context_id;
OnUpdateTransform(properties_->UpdatePerspective(
*context_.current.transform, std::move(state)));
} else {
OnClearTransform(properties_->ClearPerspective());
}
}
if (properties_->Perspective()) {
context_.current.transform = properties_->Perspective();
context_.should_flatten_inherited_transform = false;
}
}
void FragmentPaintPropertyTreeBuilder::UpdateReplacedContentTransform() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate() && !NeedsReplacedContentTransform(object_)) {
OnClearTransform(properties_->ClearReplacedContentTransform());
} else if (NeedsPaintPropertyUpdate()) {
AffineTransform content_to_parent_space;
if (object_.IsSVGRoot()) {
content_to_parent_space =
SVGRootPainter(To<LayoutSVGRoot>(object_))
.TransformToPixelSnappedBorderBox(context_.current.paint_offset);
} else if (object_.IsLayoutEmbeddedContent()) {
content_to_parent_space =
To<LayoutEmbeddedContent>(object_).EmbeddedContentTransform();
}
if (!content_to_parent_space.IsIdentity()) {
TransformPaintPropertyNode::State state;
SetTransformNodeStateFromAffineTransform(state, content_to_parent_space);
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
state.rendering_context_id = context_.rendering_context_id;
OnUpdateTransform(properties_->UpdateReplacedContentTransform(
*context_.current.transform, std::move(state)));
} else {
OnClearTransform(properties_->ClearReplacedContentTransform());
}
}
if (properties_->ReplacedContentTransform()) {
context_.current.transform = properties_->ReplacedContentTransform();
context_.should_flatten_inherited_transform = true;
context_.rendering_context_id = 0;
}
if (object_.IsSVGRoot()) {
// SVG painters don't use paint offset. The paint offset is baked into
// the transform node instead.
context_.current.paint_offset = PhysicalOffset();
context_.current.directly_composited_container_paint_offset_subpixel_delta =
PhysicalOffset();
}
}
static MainThreadScrollingReasons GetMainThreadScrollingReasons(
const LayoutObject& object,
MainThreadScrollingReasons ancestor_reasons) {
auto reasons = ancestor_reasons;
if (!object.IsBox())
return reasons;
if (IsA<LayoutView>(object)) {
if (object.GetFrameView()
->RequiresMainThreadScrollingForBackgroundAttachmentFixed()) {
reasons |=
cc::MainThreadScrollingReason::kHasBackgroundAttachmentFixedObjects;
}
// TODO(pdr): This should apply to all scrollable areas, not just the
// viewport. This is not a user-visible bug because the threaded scrolling
// setting is only for testing.
if (!object.GetFrame()->GetSettings()->GetThreadedScrollingEnabled())
reasons |= cc::MainThreadScrollingReason::kThreadedScrollingDisabled;
}
if (!object.GetFrame()->Client()->GetWebFrame()) {
// If there's no WebFrame, then there's no WebFrameWidget, and we can't do
// threaded scrolling. This currently only happens in a WebPagePopup.
// (However, we still allow needs_composited_scrolling to be true in this
// case, so that the scroller gets layerized.)
reasons |= cc::MainThreadScrollingReason::kPopupNoThreadedInput;
}
return reasons;
}
void FragmentPaintPropertyTreeBuilder::UpdateScrollAndScrollTranslation() {
DCHECK(properties_);
if (NeedsPaintPropertyUpdate()) {
if (object_.IsBox() && To<LayoutBox>(object_).NeedsScrollNode(
full_context_.direct_compositing_reasons)) {
const auto& box = To<LayoutBox>(object_);
PaintLayerScrollableArea* scrollable_area = box.GetScrollableArea();
ScrollPaintPropertyNode::State state;
PhysicalRect clip_rect =
box.OverflowClipRect(context_.current.paint_offset);
state.container_rect = ToPixelSnappedRect(clip_rect);
state.contents_size =
scrollable_area->PixelSnappedContentsSize(clip_rect.offset);
state.overflow_clip_node = properties_->OverflowClip();
state.user_scrollable_horizontal =
scrollable_area->UserInputScrollable(kHorizontalScrollbar);
state.user_scrollable_vertical =
scrollable_area->UserInputScrollable(kVerticalScrollbar);
if (state.user_scrollable_horizontal || state.user_scrollable_vertical)
object_.GetFrameView()->AddUserScrollableArea(scrollable_area);
else
object_.GetFrameView()->RemoveUserScrollableArea(scrollable_area);
// TODO(bokan): We probably don't need to pass ancestor reasons down the
// scroll tree. On the compositor, in
// LayerTreeHostImpl::FindScrollNodeForDeviceViewportPoint, we walk up
// the scroll tree looking at all the ancestor MainThreadScrollingReasons.
// https://crbug.com/985127.
auto ancestor_reasons =
context_.current.scroll->GetMainThreadScrollingReasons();
state.main_thread_scrolling_reasons =
GetMainThreadScrollingReasons(object_, ancestor_reasons);
// Main thread scrolling reasons depend on their ancestor's reasons
// so ensure the entire subtree is updated when reasons change.
if (auto* existing_scroll = properties_->Scroll()) {
if (existing_scroll->GetMainThreadScrollingReasons() !=
state.main_thread_scrolling_reasons) {
// Main thread scrolling reasons cross into isolation.
full_context_.force_subtree_update_reasons |=
PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationPiercing;
}
}
state.compositor_element_id = scrollable_area->GetScrollElementId();
state.overscroll_behavior =
cc::OverscrollBehavior(static_cast<cc::OverscrollBehavior::Type>(
box.StyleRef().OverscrollBehaviorX()),
static_cast<cc::OverscrollBehavior::Type>(
box.StyleRef().OverscrollBehaviorY()));
state.snap_container_data =
box.GetScrollableArea() &&
box.GetScrollableArea()->GetSnapContainerData()
? absl::optional<cc::SnapContainerData>(
*box.GetScrollableArea()->GetSnapContainerData())
: absl::nullopt;
OnUpdateScroll(properties_->UpdateScroll(*context_.current.scroll,
std::move(state)));
// Create opacity effect nodes for overlay scrollbars for their fade
// animation in the compositor.
if (scrollable_area->VerticalScrollbar() &&
scrollable_area->VerticalScrollbar()->IsOverlayScrollbar()) {
EffectPaintPropertyNode::State effect_state;
effect_state.local_transform_space = context_.current.transform;
effect_state.direct_compositing_reasons =
CompositingReason::kActiveOpacityAnimation;
effect_state.compositor_element_id =
scrollable_area->GetScrollbarElementId(
ScrollbarOrientation::kVerticalScrollbar);
OnUpdateEffect(properties_->UpdateVerticalScrollbarEffect(
*context_.current_effect, std::move(effect_state)));
} else {
OnClearEffect(properties_->ClearVerticalScrollbarEffect());
}
if (scrollable_area->HorizontalScrollbar() &&
scrollable_area->HorizontalScrollbar()->IsOverlayScrollbar()) {
EffectPaintPropertyNode::State effect_state;
effect_state.local_transform_space = context_.current.transform;
effect_state.direct_compositing_reasons =
CompositingReason::kActiveOpacityAnimation;
effect_state.compositor_element_id =
scrollable_area->GetScrollbarElementId(
ScrollbarOrientation::kHorizontalScrollbar);
OnUpdateEffect(properties_->UpdateHorizontalScrollbarEffect(
*context_.current_effect, std::move(effect_state)));
} else {
OnClearEffect(properties_->ClearHorizontalScrollbarEffect());
}
} else {
OnClearScroll(properties_->ClearScroll());
OnClearEffect(properties_->ClearVerticalScrollbarEffect());
OnClearEffect(properties_->ClearHorizontalScrollbarEffect());
}
// A scroll translation node is created for static offset (e.g., overflow
// hidden with scroll offset) or cases that scroll and have a scroll node.
if (NeedsScrollOrScrollTranslation(
object_, full_context_.direct_compositing_reasons)) {
const auto& box = To<LayoutBox>(object_);
DCHECK(box.GetScrollableArea());
gfx::PointF scroll_position = box.GetScrollableArea()->ScrollPosition();
TransformPaintPropertyNode::State state{
-scroll_position.OffsetFromOrigin()};
if (!box.GetScrollableArea()->PendingScrollAnchorAdjustment().IsZero()) {
context_.current.pending_scroll_anchor_adjustment +=
box.GetScrollableArea()->PendingScrollAnchorAdjustment();
box.GetScrollableArea()->ClearPendingScrollAnchorAdjustment();
}
state.flags.flattens_inherited_transform =
context_.should_flatten_inherited_transform;
state.rendering_context_id = context_.rendering_context_id;
state.direct_compositing_reasons =
full_context_.direct_compositing_reasons &
CompositingReason::kDirectReasonsForScrollTranslationProperty;
state.scroll = properties_->Scroll();
// If scroll and transform are both present, we should use the
// transform property tree node to determine visibility of the
// scrolling contents.
if (object_.HasTransform() && object_.StyleRef().BackfaceVisibility() ==
EBackfaceVisibility::kHidden) {
state.flags.delegates_to_parent_for_backface = true;
}
auto effective_change_type = properties_->UpdateScrollTranslation(
*context_.current.transform, std::move(state));
// Even if effective_change_type is kUnchanged, we might still need to
// DirectlyUpdateScrollOffsetTransform, in case the cc::TransformNode
// was also updated in LayerTreeHost::ApplyCompositorChanges.
if (effective_change_type <=
PaintPropertyChangeType::kChangedOnlySimpleValues &&
properties_->ScrollTranslation()->HasDirectCompositingReasons() &&
// In platform code, only scroll translations with scroll nodes are
// treated as scroll translations with overlap testing treatment.
// A scroll translation for overflow:hidden doesn't have a scroll node
// and needs full PaintArtifactCompositor update on scroll.
(!RuntimeEnabledFeatures::ScrollUpdateOptimizationsEnabled() ||
properties_->Scroll())) {
if (auto* paint_artifact_compositor =
object_.GetFrameView()->GetPaintArtifactCompositor()) {
bool updated =
paint_artifact_compositor->DirectlyUpdateScrollOffsetTransform(
*properties_->ScrollTranslation());
if (updated &&
effective_change_type ==
PaintPropertyChangeType::kChangedOnlySimpleValues) {
effective_change_type =
PaintPropertyChangeType::kChangedOnlyCompositedValues;
properties_->ScrollTranslation()->CompositorSimpleValuesUpdated();
}
}
}
OnUpdateTransform(effective_change_type);
} else {
OnClearTransform(properties_->ClearScrollTranslation());
}
}
if (properties_->Scroll())
context_.current.scroll = properties_->Scroll();
if (const auto* scroll_translation = properties_->ScrollTranslation()) {
context_.current.transform = scroll_translation;
// See comments for ScrollTranslation in object_paint_properties.h for the
// reason of adding ScrollOrigin().
context_.current.paint_offset +=
PhysicalOffset(To<LayoutBox>(object_).ScrollOrigin());
// A scroller creates a layout shift root, so we just calculate one scroll
// offset delta without accumulation.
context_.current.scroll_offset_to_layout_shift_root_delta =
scroll_translation->Translation2D() - full_context_.old_scroll_offset;
}
}
void FragmentPaintPropertyTreeBuilder::UpdateOutOfFlowContext() {
if (!object_.IsBoxModelObject() && !properties_)
return;
if (object_.IsLayoutBlock())
context_.paint_offset_for_float = context_.current.paint_offset;
if (object_.CanContainAbsolutePositionObjects())
context_.absolute_position = context_.current;
if (IsA<LayoutView>(object_)) {
const auto* initial_fixed_transform = context_.fixed_position.transform;
context_.fixed_position = context_.current;
context_.fixed_position.fixed_position_children_fixed_to_root = true;
// Fixed position transform should not be affected.
context_.fixed_position.transform = initial_fixed_transform;
// Scrolling in a fixed position element should chain up through the
// LayoutView.
if (properties_->Scroll())
context_.fixed_position.scroll = properties_->Scroll();
if (properties_->ScrollTranslation()) {
// Also undo the ScrollOrigin part in paint offset that was added when
// ScrollTranslation was updated.
context_.fixed_position.paint_offset -=
PhysicalOffset(To<LayoutBox>(object_).ScrollOrigin());
}
} else if (object_.CanContainFixedPositionObjects()) {
context_.fixed_position = context_.current;
context_.fixed_position.fixed_position_children_fixed_to_root = false;
} else if (properties_ && properties_->CssClip()) {
// CSS clip applies to all descendants, even if this object is not a
// containing block ancestor of the descendant. It is okay for
// absolute-position descendants because having CSS clip implies being
// absolute position container. However for fixed-position descendants we
// need to insert the clip here if we are not a containing block ancestor of
// them.
auto* css_clip = properties_->CssClip();
// Before we actually create anything, check whether in-flow context and
// fixed-position context has exactly the same clip. Reuse if possible.
if (context_.fixed_position.clip == css_clip->Parent()) {
context_.fixed_position.clip = css_clip;
} else {
if (NeedsPaintPropertyUpdate()) {
OnUpdateClip(properties_->UpdateCssClipFixedPosition(
*context_.fixed_position.clip,
ClipPaintPropertyNode::State(&css_clip->LocalTransformSpace(),
css_clip->LayoutClipRect().Rect(),
css_clip->PaintClipRect())));
}
if (properties_->CssClipFixedPosition())
context_.fixed_position.clip = properties_->CssClipFixedPosition();
return;
}
}
if (NeedsPaintPropertyUpdate() && properties_)
OnClearClip(properties_->ClearCssClipFixedPosition());
}
void FragmentPaintPropertyTreeBuilder::UpdateTransformIsolationNode() {
if (NeedsPaintPropertyUpdate()) {
if (NeedsIsolationNodes(object_)) {
OnUpdateTransform(properties_->UpdateTransformIsolationNode(
*context_.current.transform));
} else {
OnClearTransform(properties_->ClearTransformIsolationNode());
}
}
if (properties_->TransformIsolationNode())
context_.current.transform = properties_->TransformIsolationNode();
}
void FragmentPaintPropertyTreeBuilder::UpdateEffectIsolationNode() {
if (NeedsPaintPropertyUpdate()) {
if (NeedsIsolationNodes(object_)) {
OnUpdateEffect(
properties_->UpdateEffectIsolationNode(*context_.current_effect));
} else {
OnClearEffect(properties_->ClearEffectIsolationNode());
}
}
if (properties_->EffectIsolationNode())
context_.current_effect = properties_->EffectIsolationNode();
}
void FragmentPaintPropertyTreeBuilder::UpdateClipIsolationNode() {
if (NeedsPaintPropertyUpdate()) {
if (NeedsIsolationNodes(object_)) {
OnUpdateClip(
properties_->UpdateClipIsolationNode(*context_.current.clip));
} else {
OnClearClip(properties_->ClearClipIsolationNode());
}
}
if (properties_->ClipIsolationNode())
context_.current.clip = properties_->ClipIsolationNode();
}
static PhysicalRect MapLocalRectToAncestorLayer(
const LayoutBox& box,
const PhysicalRect& local_rect,
const PaintLayer& ancestor_layer) {
return box.LocalToAncestorRect(local_rect, &ancestor_layer.GetLayoutObject(),
kIgnoreTransforms);
}
static bool IsRepeatingTableSection(const LayoutObject& object) {
if (!object.IsTableSection())
return false;
const auto& section = ToInterface<LayoutNGTableSectionInterface>(object);
return section.IsRepeatingHeaderGroup() || section.IsRepeatingFooterGroup();
}
static PhysicalRect BoundingBoxInPaginationContainer(
const LayoutObject& object,
const PaintLayer& enclosing_pagination_layer) {
// The special path for fragmented layers ensures that the bounding box also
// covers contents visual overflow, so that the fragments will cover all
// fragments of contents except for self-painting layers, because we initiate
// fragment painting of contents from the layer.
if (object.HasLayer() &&
// Table section may repeat, and doesn't need the special layer path
// because it doesn't have contents visual overflow.
!object.IsTableSection()) {
const auto* layer = To<LayoutBoxModelObject>(object).Layer();
if (layer->EnclosingPaginationLayer()) {
ClipRect clip;
layer->Clipper(PaintLayer::GeometryMapperOption::kDoNotUseGeometryMapper)
.CalculateBackgroundClipRect(
ClipRectsContext(&enclosing_pagination_layer, nullptr), clip);
return Intersection(
clip.Rect(), layer->PhysicalBoundingBox(&enclosing_pagination_layer));
}
}
PhysicalRect local_bounds;
const LayoutBox* local_space_object = nullptr;
if (object.IsBox()) {
local_space_object = To<LayoutBox>(&object);
local_bounds = local_space_object->PhysicalBorderBoxRect();
} else {
// Non-boxes paint in the space of their containing block.
local_space_object = object.ContainingBlock();
// For non-SVG we can get a more accurate result with LocalVisualRect,
// instead of falling back to the bounds of the enclosing block.
if (!object.IsSVG()) {
local_bounds = object.LocalVisualRect();
} else {
local_bounds = PhysicalRect::EnclosingRect(
SVGLayoutSupport::LocalVisualRect(object));
}
}
// The link highlight covers block visual overflows, continuations, etc. which
// may intersect with more fragments than the object itself.
if (IsLinkHighlighted(object)) {
local_bounds.Unite(UnionRect(
object.OutlineRects(nullptr, PhysicalOffset(),
NGOutlineType::kIncludeBlockVisualOverflow)));
}
// Compute the bounding box without transforms.
auto bounding_box = MapLocalRectToAncestorLayer(
*local_space_object, local_bounds, enclosing_pagination_layer);
if (!IsRepeatingTableSection(object))
return bounding_box;
const auto& section = ToInterface<LayoutNGTableSectionInterface>(object);
const auto& table = *section.TableInterface();
if (section.IsRepeatingHeaderGroup()) {
// Now bounding_box covers the original header. Expand it to intersect
// with all fragments containing the original and repeatings, i.e. to
// intersect any fragment containing any row.
if (const auto* bottom_section = table.LastNonEmptySectionInterface()) {
const auto* bottom_section_box =
To<LayoutBox>(bottom_section->ToLayoutObject());
bounding_box.Unite(MapLocalRectToAncestorLayer(
*bottom_section_box, bottom_section_box->PhysicalBorderBoxRect(),
enclosing_pagination_layer));
}
return bounding_box;
}
DCHECK(section.IsRepeatingFooterGroup());
// Similar to repeating header, expand bounding_box to intersect any
// fragment containing any row first.
if (const auto* top_section = table.FirstNonEmptySectionInterface()) {
const auto* top_section_box = To<LayoutBox>(top_section->ToLayoutObject());
bounding_box.Unite(MapLocalRectToAncestorLayer(
*top_section_box, top_section_box->PhysicalBorderBoxRect(),
enclosing_pagination_layer));
// However, the first fragment intersecting the expanded bounding_box may
// not have enough space to contain the repeating footer. Exclude the
// total height of the first row and repeating footers from the top of
// bounding_box to exclude the first fragment without enough space.
LayoutUnit top_exclusion = table.RowOffsetFromRepeatingFooter();
if (top_section != &section) {
top_exclusion +=
To<LayoutBox>(top_section->FirstRowInterface()->ToLayoutObject())
->LogicalHeight() +
table.VBorderSpacing();
}
// Subtract 1 to ensure overlap of 1 px for a fragment that has exactly
// one row plus space for the footer.
if (top_exclusion)
top_exclusion -= 1;
bounding_box.ShiftTopEdgeTo(bounding_box.Y() + top_exclusion);
}
return bounding_box;
}
static PhysicalOffset PaintOffsetInPaginationContainer(
const LayoutObject& object,
const PaintLayer& enclosing_pagination_layer) {
// Non-boxes use their containing blocks' paint offset.
if (!object.IsBox() && !object.HasLayer()) {
return PaintOffsetInPaginationContainer(*object.ContainingBlock(),
enclosing_pagination_layer);
}
return object.LocalToAncestorPoint(
PhysicalOffset(), &enclosing_pagination_layer.GetLayoutObject(),
kIgnoreTransforms);
}
void FragmentPaintPropertyTreeBuilder::UpdatePaintOffset() {
// Paint offsets for fragmented content are computed from scratch.
const auto* enclosing_pagination_layer =
full_context_.painting_layer->EnclosingPaginationLayer();
if (enclosing_pagination_layer &&
// Except if the paint_offset_root is below the pagination container, in
// which case fragmentation offsets are already baked into the paint
// offset transform for paint_offset_root.
!context_.current.paint_offset_root->PaintingLayer()
->EnclosingPaginationLayer()) {
if (object_.StyleRef().GetPosition() == EPosition::kAbsolute) {
context_.current = context_.absolute_position;
} else if (object_.StyleRef().GetPosition() == EPosition::kFixed) {
context_.current = context_.fixed_position;
}
// Set fragment visual paint offset.
PhysicalOffset paint_offset =
PaintOffsetInPaginationContainer(object_, *enclosing_pagination_layer);
paint_offset += fragment_data_.LegacyPaginationOffset();
paint_offset += context_.repeating_paint_offset_adjustment;
paint_offset +=
VisualOffsetFromPaintOffsetRoot(context_, enclosing_pagination_layer);
// The paint offset root can have a subpixel paint offset adjustment. The
// paint offset root always has one fragment.
const auto& paint_offset_root_fragment =
context_.current.paint_offset_root->FirstFragment();
paint_offset += paint_offset_root_fragment.PaintOffset();
context_.current.paint_offset = paint_offset;
return;
}
if (!pre_paint_info_) {
if (object_.IsFloating() && !object_.IsInLayoutNGInlineFormattingContext())
context_.current.paint_offset = context_.paint_offset_for_float;
// Multicolumn spanners are painted starting at the multicolumn container
// (but still inherit properties in layout-tree order) so reset the paint
// offset.
if (object_.IsColumnSpanAll()) {
context_.current.paint_offset =
object_.Container()->FirstFragment().PaintOffset();
}
}
if (object_.IsBoxModelObject()) {
const auto& box_model_object = To<LayoutBoxModelObject>(object_);
switch (box_model_object.StyleRef().GetPosition()) {
case EPosition::kStatic:
break;
case EPosition::kRelative:
context_.current.paint_offset +=
box_model_object.OffsetForInFlowPosition();
break;
case EPosition::kAbsolute: {
DCHECK_EQ(full_context_.container_for_absolute_position,
box_model_object.Container());
SwitchToOOFContext(context_.absolute_position);
// Absolutely positioned content in an inline should be positioned
// relative to the inline.
const LayoutObject* container =
full_context_.container_for_absolute_position;
if (container && container->IsLayoutInline()) {
DCHECK(container->CanContainAbsolutePositionObjects());
DCHECK(box_model_object.IsBox());
context_.current.paint_offset +=
To<LayoutInline>(container)->OffsetForInFlowPositionedInline(
To<LayoutBox>(box_model_object));
}
break;
}
case EPosition::kSticky:
break;
case EPosition::kFixed: {
DCHECK_EQ(full_context_.container_for_fixed_position,
box_model_object.Container());
SwitchToOOFContext(context_.fixed_position);
// Fixed-position elements that are fixed to the viewport have a
// transform above the scroll of the LayoutView. Child content is
// relative to that transform, and hence the fixed-position element.
if (context_.fixed_position.fixed_position_children_fixed_to_root)
context_.current.paint_offset_root = &box_model_object;
const LayoutObject* container =
full_context_.container_for_fixed_position;
if (container && container->IsLayoutInline()) {
DCHECK(container->CanContainFixedPositionObjects());
DCHECK(box_model_object.IsBox());
context_.current.paint_offset +=
To<LayoutInline>(container)->OffsetForInFlowPositionedInline(
To<LayoutBox>(box_model_object));
}
break;
}
default:
NOTREACHED();
}
}
if (const auto* box = DynamicTo<LayoutBox>(&object_)) {
if (pre_paint_info_) {
context_.current.paint_offset += pre_paint_info_->paint_offset;
// Determine whether we're inside block fragmentation or not. OOF
// descendants need special treatment inside block fragmentation.
context_.current.is_in_block_fragmentation =
pre_paint_info_->fragmentainer_is_oof_containing_block &&
box->GetNGPaginationBreakability() != LayoutBox::kForbidBreaks;
} else {
// TODO(pdr): Several calls in this function walk back up the tree to
// calculate containers (e.g., physicalLocation,
// offsetForInFlowPosition*). The containing block and other containers
// can be stored on PaintPropertyTreeBuilderFragmentContext instead of
// recomputing them.
context_.current.paint_offset += box->PhysicalLocation();
// This is a weird quirk that table cells paint as children of table rows,
// but their location have the row's location baked-in.
// Similar adjustment is done in LayoutTableCell::offsetFromContainer().
if (object_.IsTableCellLegacy()) {
LayoutObject* parent_row = object_.Parent();
DCHECK(parent_row && parent_row->IsTableRow());
context_.current.paint_offset -=
To<LayoutBox>(parent_row)->PhysicalLocation();
}
}
}
context_.current.paint_offset += context_.repeating_paint_offset_adjustment;
context_.current.additional_offset_to_layout_shift_root_delta +=
context_.pending_additional_offset_to_layout_shift_root_delta;
context_.pending_additional_offset_to_layout_shift_root_delta =
PhysicalOffset();
}
void FragmentPaintPropertyTreeBuilder::SetNeedsPaintPropertyUpdateIfNeeded() {
if (object_.HasLayer()) {
PaintLayer* layer = To<LayoutBoxModelObject>(object_).Layer();
layer->UpdateFilterReferenceBox();
}
if (!object_.IsBox())
return;
const LayoutBox& box = To<LayoutBox>(object_);
if (box.IsLayoutReplaced() &&
box.PreviousPhysicalContentBoxRect() != box.PhysicalContentBoxRect()) {
box.GetMutableForPainting().SetOnlyThisNeedsPaintPropertyUpdate();
if (box.IsLayoutEmbeddedContent()) {
if (const auto* child_view =
To<LayoutEmbeddedContent>(box).ChildLayoutView()) {
child_view->GetMutableForPainting()
.SetOnlyThisNeedsPaintPropertyUpdate();
}
}
}
if (box.Size() == box.PreviousSize())
return;
// CSS mask and clip-path comes with an implicit clip to the border box.
// Currently only CAP generate and take advantage of those.
const bool box_generates_property_nodes_for_mask_and_clip_path =
box.HasMask() || box.HasClipPath();
// The overflow clip paint property depends on the border box rect through
// overflowClipRect(). The border box rect's size equals the frame rect's
// size so we trigger a paint property update when the frame rect changes.
if (NeedsOverflowClip(box) || NeedsInnerBorderRadiusClip(box) ||
// The used value of CSS clip may depend on size of the box, e.g. for
// clip: rect(auto auto auto -5px).
NeedsCssClip(box) ||
// Relative lengths (e.g., percentage values) in transform, perspective,
// transform-origin, and perspective-origin can depend on the size of the
// frame rect, so force a property update if it changes. TODO(pdr): We
// only need to update properties if there are relative lengths.
box.HasTransform() || NeedsPerspective(box) ||
box_generates_property_nodes_for_mask_and_clip_path) {
box.GetMutableForPainting().SetOnlyThisNeedsPaintPropertyUpdate();
}
// The filter generated for reflection depends on box size.
if (box.HasReflection()) {
DCHECK(box.HasLayer());
box.Layer()->SetFilterOnEffectNodeDirty();
box.GetMutableForPainting().SetOnlyThisNeedsPaintPropertyUpdate();
}
}
void FragmentPaintPropertyTreeBuilder::UpdateForObjectLocationAndSize(
absl::optional<gfx::Vector2d>& paint_offset_translation) {
context_.old_paint_offset = fragment_data_.PaintOffset();
UpdatePaintOffset();
UpdateForPaintOffsetTranslation(paint_offset_translation);
PhysicalOffset paint_offset_delta =
fragment_data_.PaintOffset() - context_.current.paint_offset;
if (!paint_offset_delta.IsZero()) {
// Many paint properties depend on paint offset so we force an update of
// the entire subtree on paint offset changes.
full_context_.force_subtree_update_reasons |=
PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationBlocked;
object_.GetMutableForPainting().SetShouldCheckForPaintInvalidation();
fragment_data_.SetPaintOffset(context_.current.paint_offset);
if (object_.IsBox()) {
// See PaintLayerScrollableArea::PixelSnappedBorderBoxSize() for the
// reason of this.
if (auto* scrollable_area = To<LayoutBox>(object_).GetScrollableArea())
scrollable_area->PositionOverflowControls();
}
object_.GetMutableForPainting().InvalidateIntersectionObserverCachedRects();
object_.GetFrameView()->SetIntersectionObservationState(
LocalFrameView::kDesired);
}
if (paint_offset_translation)
context_.current.paint_offset_root = &To<LayoutBoxModelObject>(object_);
}
static bool IsLayoutShiftRoot(const LayoutObject& object,
const FragmentData& fragment) {
const auto* properties = fragment.PaintProperties();
if (!properties)
return false;
if (IsA<LayoutView>(object))
return true;
for (const TransformPaintPropertyNode* transform :
properties->AllCSSTransformPropertiesOutsideToInside()) {
if (transform && !transform->IsIdentityOr2DTranslation())
return true;
}
if (properties->ReplacedContentTransform())
return true;
if (properties->TransformIsolationNode())
return true;
if (auto* offset_translation = properties->PaintOffsetTranslation()) {
if (offset_translation->RequiresCompositingForFixedPosition())
return true;
}
if (auto* sticky_translation = properties->StickyTranslation())
return true;
if (auto* anchor_scroll_translation = properties->AnchorScrollTranslation())
return true;
if (properties->OverflowClip())
return true;
return false;
}
void FragmentPaintPropertyTreeBuilder::UpdateForSelf() {
#if DCHECK_IS_ON()
absl::optional<FindPaintOffsetNeedingUpdateScope> check_paint_offset;
if (RuntimeEnabledFeatures::PaintUnderInvalidationCheckingEnabled()) {
check_paint_offset.emplace(object_, fragment_data_,
full_context_.is_actually_needed);
}
#endif
// This is not in FindObjectPropertiesNeedingUpdateScope because paint offset
// can change without NeedsPaintPropertyUpdate.
absl::optional<gfx::Vector2d> paint_offset_translation;
UpdateForObjectLocationAndSize(paint_offset_translation);
if (&fragment_data_ == &object_.FirstFragment())
SetNeedsPaintPropertyUpdateIfNeeded();
if (properties_) {
{
#if DCHECK_IS_ON()
absl::optional<FindPropertiesNeedingUpdateScope> check_fragment_clip;
if (RuntimeEnabledFeatures::PaintUnderInvalidationCheckingEnabled()) {
bool force_subtree_update = full_context_.force_subtree_update_reasons;
check_fragment_clip.emplace(object_, fragment_data_,
force_subtree_update);
}
#endif
UpdateFragmentClip();
}
// Update of PaintOffsetTranslation is checked by
// FindPaintOffsetNeedingUpdateScope.
UpdatePaintOffsetTranslation(paint_offset_translation);
}
#if DCHECK_IS_ON()
absl::optional<FindPropertiesNeedingUpdateScope> check_paint_properties;
if (RuntimeEnabledFeatures::PaintUnderInvalidationCheckingEnabled()) {
bool force_subtree_update = full_context_.force_subtree_update_reasons;
check_paint_properties.emplace(object_, fragment_data_,
force_subtree_update);
}
#endif
if (properties_) {
UpdateStickyTranslation();
UpdateAnchorScrollTranslation();
if (object_.IsSVGChild()) {
// TODO(crbug.com/1278452): Merge SVG handling into the primary codepath.
UpdateTransformForSVGChild(full_context_.direct_compositing_reasons);
} else {
UpdateTranslate();
UpdateRotate();
UpdateScale();
UpdateOffset();
UpdateTransform();
}
UpdateSharedElementTransitionEffect();
UpdateClipPathClip();
UpdateEffect();
UpdateCssClip();
UpdateFilter();
UpdateOverflowControlsClip();
} else if (object_.IsForElement()) {
// 3D rendering contexts follow the DOM ancestor chain, so
// flattening should apply regardless of presence of transform.
context_.rendering_context_id = 0;
context_.should_flatten_inherited_transform = true;
}
UpdateLocalBorderBoxContext();
UpdateLayoutShiftRootChanged(IsLayoutShiftRoot(object_, fragment_data_));
// For LayoutView, additional_offset_to_layout_shift_root_delta applies to
// neither itself nor descendants. For other layout shift roots, we clear the
// delta at the end of UpdateForChildren() because the delta still applies to
// the object itself. Same for translation_2d_to_layout_shift_delta and
// scroll_offset_to_layout_shift_root_delta.
if (IsA<LayoutView>(object_)) {
context_.current.additional_offset_to_layout_shift_root_delta =
PhysicalOffset();
context_.translation_2d_to_layout_shift_root_delta = gfx::Vector2dF();
context_.current.scroll_offset_to_layout_shift_root_delta =
gfx::Vector2dF();
}
}
void FragmentPaintPropertyTreeBuilder::UpdateForChildren() {
#if DCHECK_IS_ON()
// Will be used though a reference by check_paint_offset, so it's declared
// here to out-live check_paint_offset. It's false because paint offset
// should not change during this function.
const bool needs_paint_offset_update = false;
absl::optional<FindPaintOffsetNeedingUpdateScope> check_paint_offset;
absl::optional<FindPropertiesNeedingUpdateScope> check_paint_properties;
if (RuntimeEnabledFeatures::PaintUnderInvalidationCheckingEnabled()) {
check_paint_offset.emplace(object_, fragment_data_,
needs_paint_offset_update);
bool force_subtree_update = full_context_.force_subtree_update_reasons;
check_paint_properties.emplace(object_, fragment_data_,
force_subtree_update);
}
#endif
if (properties_) {
UpdateInnerBorderRadiusClip();
UpdateOverflowClip();
UpdatePerspective();
UpdateReplacedContentTransform();
UpdateScrollAndScrollTranslation();
UpdateTransformIsolationNode();
UpdateEffectIsolationNode();
UpdateClipIsolationNode();
}
UpdateOutOfFlowContext();
bool is_layout_shift_root = IsLayoutShiftRoot(object_, fragment_data_);
UpdateLayoutShiftRootChanged(is_layout_shift_root);
if (full_context_.was_layout_shift_root || is_layout_shift_root) {
// A layout shift root (e.g. with mere OverflowClip) may have non-zero
// paint offset. Exclude the layout shift root's paint offset delta from
// additional_offset_to_layout_shift_root_delta.
context_.current.additional_offset_to_layout_shift_root_delta =
context_.old_paint_offset - fragment_data_.PaintOffset();
context_.translation_2d_to_layout_shift_root_delta = gfx::Vector2dF();
// Don't reset scroll_offset_to_layout_shift_root_delta if this object has
// scroll translation because we need to propagate the delta to descendants.
if (!properties_ || !properties_->ScrollTranslation()) {
context_.current.scroll_offset_to_layout_shift_root_delta =
gfx::Vector2dF();
context_.current.pending_scroll_anchor_adjustment = gfx::Vector2dF();
}
}
#if DCHECK_IS_ON()
if (properties_)
properties_->Validate();
#endif
}
void FragmentPaintPropertyTreeBuilder::UpdateLayoutShiftRootChanged(
bool is_layout_shift_root) {
if (is_layout_shift_root != full_context_.was_layout_shift_root) {
context_.current.layout_shift_root_changed = true;
} else if (is_layout_shift_root && full_context_.was_layout_shift_root) {
context_.current.layout_shift_root_changed = false;
}
}
} // namespace
void PaintPropertyTreeBuilder::InitFragmentPaintProperties(
FragmentData& fragment,
bool needs_paint_properties,
PaintPropertyTreeBuilderFragmentContext& context) {
if (const auto* properties = fragment.PaintProperties()) {
if (const auto* translation = properties->PaintOffsetTranslation()) {
// If there is a paint offset translation, it only causes a net change
// in additional_offset_to_layout_shift_root_delta by the amount the
// paint offset translation changed from the prior frame. To implement
// this, we record a negative offset here, and then re-add it in
// UpdatePaintOffsetTranslation. The net effect is that the value
// of additional_offset_to_layout_shift_root_delta is the difference
// between the old and new paint offset translation.
context.pending_additional_offset_to_layout_shift_root_delta =
-PhysicalOffset::FromVector2dFRound(translation->Translation2D());
}
gfx::Vector2dF translation2d;
for (const TransformPaintPropertyNode* transform :
properties->AllCSSTransformPropertiesOutsideToInside()) {
if (transform) {
if (transform->IsIdentityOr2DTranslation()) {
translation2d += transform->Translation2D();
} else {
translation2d = gfx::Vector2dF();
break;
}
}
}
context.translation_2d_to_layout_shift_root_delta -= translation2d;
}
if (needs_paint_properties) {
fragment.EnsurePaintProperties();
} else if (auto* properties = fragment.PaintProperties()) {
if (properties->HasTransformNode()) {
properties_changed_.transform_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
if (properties->HasClipNode()) {
properties_changed_.clip_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
if (properties->HasEffectNode()) {
properties_changed_.effect_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
if (properties->Scroll()) {
properties_changed_.scroll_changed =
PaintPropertyChangeType::kNodeAddedOrRemoved;
}
fragment.ClearPaintProperties();
}
}
void PaintPropertyTreeBuilder::InitFragmentPaintPropertiesForLegacy(
FragmentData& fragment,
bool needs_paint_properties,
const PhysicalOffset& pagination_offset,
PaintPropertyTreeBuilderFragmentContext& context) {
DCHECK(!IsInNGFragmentTraversal());
InitFragmentPaintProperties(fragment, needs_paint_properties, context);
if (context.current.fragmentainer_idx == WTF::kNotFound) {
fragment.SetLegacyPaginationOffset(pagination_offset);
fragment.SetLogicalTopInFlowThread(context.logical_top_in_flow_thread);
} else {
// We're inside (monolithic) legacy content, but further out there's an NG
// fragmentation context. Use the fragmentainer index, just like we do for
// NG objects.
fragment.SetFragmentID(context.current.fragmentainer_idx);
}
}
void PaintPropertyTreeBuilder::InitFragmentPaintPropertiesForNG(
bool needs_paint_properties) {
if (context_.fragments.IsEmpty())
context_.fragments.push_back(PaintPropertyTreeBuilderFragmentContext());
else
context_.fragments.resize(1);
context_.fragments[0].current.fragmentainer_idx =
pre_paint_info_->fragmentainer_idx;
InitFragmentPaintProperties(*pre_paint_info_->fragment_data,
needs_paint_properties, context_.fragments[0]);
}
void PaintPropertyTreeBuilder::InitSingleFragmentFromParent(
bool needs_paint_properties) {
FragmentData& first_fragment =
object_.GetMutableForPainting().FirstFragment();
first_fragment.ClearNextFragment();
if (context_.fragments.IsEmpty()) {
context_.fragments.push_back(PaintPropertyTreeBuilderFragmentContext());
} else {
context_.fragments.resize(1);
context_.fragments[0].fragment_clip.reset();
context_.fragments[0].logical_top_in_flow_thread = LayoutUnit();
}
InitFragmentPaintPropertiesForLegacy(first_fragment, needs_paint_properties,
PhysicalOffset(), context_.fragments[0]);
// Column-span:all skips pagination container in the tree hierarchy, so it
// should also skip any fragment clip created by the skipped pagination
// container. We also need to skip fragment clip if the layer doesn't allow
// fragmentation.
if (!object_.IsColumnSpanAll())
return;
const auto* pagination_layer_in_tree_hierarchy =
object_.Parent()->EnclosingLayer()->EnclosingPaginationLayer();
if (!pagination_layer_in_tree_hierarchy)
return;
const auto& clip_container =
pagination_layer_in_tree_hierarchy->GetLayoutObject();
const auto* properties = clip_container.FirstFragment().PaintProperties();
if (!properties || !properties->FragmentClip())
return;
// However, because we don't allow an object's clip to escape the
// output clip of the object's effect, we can't skip fragment clip if
// between this object and the container there is any effect that has
// an output clip. TODO(crbug.com/803649): Fix this workaround.
const auto& clip_container_effect = clip_container.FirstFragment()
.LocalBorderBoxProperties()
.Effect()
.Unalias();
for (const auto* effect = &context_.fragments[0].current_effect->Unalias();
effect && effect != &clip_container_effect;
effect = effect->UnaliasedParent()) {
if (effect->OutputClip())
return;
}
// Skip the fragment clip.
context_.fragments[0].current.clip = properties->FragmentClip()->Parent();
}
void PaintPropertyTreeBuilder::
UpdateRepeatingTableSectionPaintOffsetAdjustment() {
if (!context_.repeating_table_section)
return;
if (object_ == context_.repeating_table_section->ToLayoutObject()) {
if (ToInterface<LayoutNGTableSectionInterface>(object_)
.IsRepeatingHeaderGroup())
UpdateRepeatingTableHeaderPaintOffsetAdjustment();
else if (ToInterface<LayoutNGTableSectionInterface>(object_)
.IsRepeatingFooterGroup())
UpdateRepeatingTableFooterPaintOffsetAdjustment();
} else if (!context_.painting_layer->EnclosingPaginationLayer()) {
// When repeating a table section in paged media, paint_offset is inherited
// by descendants, so we only need to adjust point offset for the table
// section.
for (auto& fragment_context : context_.fragments) {
fragment_context.repeating_paint_offset_adjustment = PhysicalOffset();
}
}
// Otherwise the object is a descendant of the object which initiated the
// repeating. It just uses repeating_paint_offset_adjustment in its fragment
// contexts inherited from the initiating object.
}
// TODO(wangxianzhu): For now this works for horizontal-bt writing mode only.
// Need to support vertical writing modes.
void PaintPropertyTreeBuilder::
UpdateRepeatingTableHeaderPaintOffsetAdjustment() {
const auto& section = ToInterface<LayoutNGTableSectionInterface>(object_);
DCHECK(section.IsRepeatingHeaderGroup());
LayoutUnit fragment_height;
LayoutUnit original_offset_in_flow_thread =
context_.repeating_table_section_bounding_box.Y();
LayoutUnit original_offset_in_fragment;
const LayoutFlowThread* flow_thread = nullptr;
if (const auto* pagination_layer =
context_.painting_layer->EnclosingPaginationLayer()) {
flow_thread = &To<LayoutFlowThread>(pagination_layer->GetLayoutObject());
// TODO(crbug.com/757947): This shouldn't be possible but happens to
// column-spanners in nested multi-col contexts.
if (!flow_thread->IsPageLogicalHeightKnown())
return;
fragment_height =
flow_thread->PageLogicalHeightForOffset(original_offset_in_flow_thread);
original_offset_in_fragment =
fragment_height - flow_thread->PageRemainingLogicalHeightForOffset(
original_offset_in_flow_thread,
LayoutBox::kAssociateWithLatterPage);
} else {
// The containing LayoutView serves as the virtual pagination container
// for repeating table section in paged media.
fragment_height = object_.View()->PageLogicalHeight();
original_offset_in_fragment =
IntMod(original_offset_in_flow_thread, fragment_height);
}
const LayoutNGTableInterface& table = *section.TableInterface();
// This is total height of repeating headers seen by the table - height of
// this header (which is the lowest repeating header seen by this table.
auto repeating_offset_in_fragment =
table.RowOffsetFromRepeatingHeader() -
To<LayoutBox>(section.ToLayoutObject())->LogicalHeight();
// For a repeating table header, the original location (which may be in the
// middle of the fragment) and repeated locations (which should be always,
// together with repeating headers of outer tables, aligned to the top of
// the fragments) may be different. Therefore, for fragments other than the
// first, adjust by |alignment_offset|.
auto adjustment = repeating_offset_in_fragment - original_offset_in_fragment;
auto fragment_offset_in_flow_thread =
original_offset_in_flow_thread - original_offset_in_fragment;
// It's the table sections that make room for repeating headers. Stop
// repeating when we're past the last section. There may be trailing
// border-spacing, and also bottom captions. No room has been made for a
// repeated header there.
auto sections_logical_height =
To<LayoutBox>(table.LastSectionInterface()->ToLayoutObject())
->LogicalBottom() -
To<LayoutBox>(table.FirstSectionInterface()->ToLayoutObject())
->LogicalTop();
auto content_remaining = sections_logical_height - table.VBorderSpacing();
for (wtf_size_t i = 0; i < context_.fragments.size(); ++i) {
auto& fragment_context = context_.fragments[i];
fragment_context.repeating_paint_offset_adjustment = PhysicalOffset();
// Adjust paint offsets of repeatings (not including the original).
if (i)
fragment_context.repeating_paint_offset_adjustment.top = adjustment;
// Calculate the adjustment for the repeating which will appear in the next
// fragment.
adjustment += fragment_height;
if (adjustment >= content_remaining)
break;
// Calculate the offset of the next fragment in flow thread. It's used to
// get the height of that fragment.
fragment_offset_in_flow_thread += fragment_height;
if (flow_thread) {
fragment_height = flow_thread->PageLogicalHeightForOffset(
fragment_offset_in_flow_thread);
}
}
}
void PaintPropertyTreeBuilder::
UpdateRepeatingTableFooterPaintOffsetAdjustment() {
const auto& section = ToInterface<LayoutNGTableSectionInterface>(object_);
DCHECK(section.IsRepeatingFooterGroup());
LayoutUnit fragment_height;
LayoutUnit original_offset_in_flow_thread =
context_.repeating_table_section_bounding_box.Bottom() -
To<LayoutBox>(section.ToLayoutObject())->LogicalHeight();
LayoutUnit original_offset_in_fragment;
const LayoutFlowThread* flow_thread = nullptr;
if (const auto* pagination_layer =
context_.painting_layer->EnclosingPaginationLayer()) {
flow_thread = &To<LayoutFlowThread>(pagination_layer->GetLayoutObject());
// TODO(crbug.com/757947): This shouldn't be possible but happens to
// column-spanners in nested multi-col contexts.
if (!flow_thread->IsPageLogicalHeightKnown())
return;
fragment_height =
flow_thread->PageLogicalHeightForOffset(original_offset_in_flow_thread);
original_offset_in_fragment =
fragment_height - flow_thread->PageRemainingLogicalHeightForOffset(
original_offset_in_flow_thread,
LayoutBox::kAssociateWithLatterPage);
} else {
// The containing LayoutView serves as the virtual pagination container
// for repeating table section in paged media.
fragment_height = object_.View()->PageLogicalHeight();
original_offset_in_fragment =
IntMod(original_offset_in_flow_thread, fragment_height);
}
const auto& table = *section.TableInterface();
// TODO(crbug.com/798153): This keeps the existing behavior of repeating
// footer painting in TableSectionPainter. Should change both places when
// tweaking border-spacing for repeating footers.
auto repeating_offset_in_fragment = fragment_height -
table.RowOffsetFromRepeatingFooter() -
table.VBorderSpacing();
// We should show the whole bottom border instead of half if the table
// collapses borders.
if (table.ShouldCollapseBorders()) {
repeating_offset_in_fragment -=
To<LayoutBox>(table.ToLayoutObject())->BorderBottom();
}
// Similar to repeating header, this is to adjust the repeating footer from
// its original location to the repeating location.
auto adjustment = repeating_offset_in_fragment - original_offset_in_fragment;
auto fragment_offset_in_flow_thread =
original_offset_in_flow_thread - original_offset_in_fragment;
for (auto i = context_.fragments.size(); i > 0; --i) {
auto& fragment_context = context_.fragments[i - 1];
fragment_context.repeating_paint_offset_adjustment = PhysicalOffset();
// Adjust paint offsets of repeatings.
if (i != context_.fragments.size())
fragment_context.repeating_paint_offset_adjustment.top = adjustment;
// Calculate the adjustment for the repeating which will appear in the
// previous fragment.
adjustment -= fragment_height;
// Calculate the offset of the previous fragment in flow thread. It's used
// to get the height of that fragment.
fragment_offset_in_flow_thread -= fragment_height;
if (flow_thread) {
fragment_height = flow_thread->PageLogicalHeightForOffset(
fragment_offset_in_flow_thread);
}
}
}
static LayoutUnit FragmentLogicalTopInParentFlowThread(
const LayoutFlowThread& flow_thread,
LayoutUnit logical_top_in_current_flow_thread) {
const auto* parent_pagination_layer =
flow_thread.Layer()->Parent()->EnclosingPaginationLayer();
if (!parent_pagination_layer)
return LayoutUnit();
const auto* parent_flow_thread =
&To<LayoutFlowThread>(parent_pagination_layer->GetLayoutObject());
LayoutPoint location(LayoutUnit(), logical_top_in_current_flow_thread);
// TODO(crbug.com/467477): Should we flip for writing-mode? For now regardless
// of flipping, fast/multicol/vertical-rl/nested-columns.html fails.
if (!flow_thread.IsHorizontalWritingMode())
location = location.TransposedPoint();
// Convert into parent_flow_thread's coordinates.
location = flow_thread
.LocalToAncestorPoint(PhysicalOffsetToBeNoop(location),
parent_flow_thread)
.ToLayoutPoint();
if (!parent_flow_thread->IsHorizontalWritingMode())
location = location.TransposedPoint();
if (location.X() >= parent_flow_thread->LogicalWidth()) {
// TODO(crbug.com/803649): We hit this condition for
// external/wpt/css/css-multicol/multicol-height-block-child-001.xht.
// The normal path would cause wrong FragmentClip hierarchy.
// Return -1 to force standalone FragmentClip in the case.
return LayoutUnit(-1);
}
// Return the logical top of the containing fragment in parent_flow_thread.
return location.Y() +
parent_flow_thread->PageRemainingLogicalHeightForOffset(
location.Y(), LayoutBox::kAssociateWithLatterPage) -
parent_flow_thread->PageLogicalHeightForOffset(location.Y());
}
// Find from parent contexts with matching |logical_top_in_flow_thread|, if any,
// to allow for correct property tree parenting of fragments.
PaintPropertyTreeBuilderFragmentContext
PaintPropertyTreeBuilder::ContextForFragment(
const absl::optional<PhysicalRect>& fragment_clip,
LayoutUnit logical_top_in_flow_thread) const {
DCHECK(!IsInNGFragmentTraversal());
const auto& parent_fragments = context_.fragments;
if (parent_fragments.IsEmpty())
return PaintPropertyTreeBuilderFragmentContext();
// This will be used in the loop finding matching fragment from ancestor flow
// threads after no matching from parent_fragments.
LayoutUnit logical_top_in_containing_flow_thread;
bool crossed_flow_thread = false;
if (object_.IsLayoutFlowThread()) {
const auto& flow_thread = To<LayoutFlowThread>(object_);
// If this flow thread is under another flow thread, find the fragment in
// the parent flow thread containing this fragment. Otherwise, the following
// code will just match parent_contexts[0].
logical_top_in_containing_flow_thread =
FragmentLogicalTopInParentFlowThread(flow_thread,
logical_top_in_flow_thread);
for (const auto& parent_context : parent_fragments) {
if (logical_top_in_containing_flow_thread ==
parent_context.logical_top_in_flow_thread) {
auto context = parent_context;
context.fragment_clip = fragment_clip;
context.logical_top_in_flow_thread = logical_top_in_flow_thread;
return context;
}
}
crossed_flow_thread = true;
} else {
bool parent_is_under_same_flow_thread;
auto* pagination_layer =
context_.painting_layer->EnclosingPaginationLayer();
if (object_.IsColumnSpanAll()) {
parent_is_under_same_flow_thread = false;
} else if (object_.IsOutOfFlowPositioned()) {
parent_is_under_same_flow_thread =
(object_.Parent()->PaintingLayer()->EnclosingPaginationLayer() ==
pagination_layer);
} else {
parent_is_under_same_flow_thread = true;
}
// Match against parent_fragments if the fragment and parent_fragments are
// under the same flow thread.
if (parent_is_under_same_flow_thread) {
#if DCHECK_IS_ON()
// See LayoutObject::PaintingLayer() for special rules for floats inside
// inlines (legacy layout).
if (object_.Parent()->IsInline() && object_.IsFloating()) {
DCHECK(!object_.IsInLayoutNGInlineFormattingContext());
DCHECK_EQ(object_.PaintingLayer()->EnclosingPaginationLayer(),
pagination_layer);
} else {
DCHECK_EQ(object_.Parent()->PaintingLayer()->EnclosingPaginationLayer(),
pagination_layer);
}
#endif
for (const auto& parent_context : parent_fragments) {
if (logical_top_in_flow_thread ==
parent_context.logical_top_in_flow_thread) {
auto context = parent_context;
// The context inherits fragment clip from parent so we don't need
// to issue fragment clip again.
context.fragment_clip = absl::nullopt;
return context;
}
}
}
logical_top_in_containing_flow_thread = logical_top_in_flow_thread;
crossed_flow_thread = !parent_is_under_same_flow_thread;
}
// Found no matching parent fragment. Use parent_fragments[0] to inherit
// transforms and effects from ancestors, and adjust the clip state.
// TODO(crbug.com/803649): parent_fragments[0] is not always correct because
// some ancestor transform/effect may be missing in the fragment if the
// ancestor doesn't intersect with the first fragment of the flow thread.
auto context = parent_fragments[0];
context.logical_top_in_flow_thread = logical_top_in_flow_thread;
context.fragment_clip = fragment_clip;
// We reach here because of the following reasons:
// 1. the parent doesn't have the corresponding fragment because the fragment
// overflows the parent;
// 2. the fragment and parent_fragments are not under the same flow thread
// (e.g. column-span:all or some out-of-flow positioned).
// For each case, we need to adjust context.current.clip. For now it's the
// first parent fragment's FragmentClip which is not the correct clip for
// object_.
const ClipPaintPropertyNodeOrAlias* found_clip = nullptr;
for (const auto* container = object_.Container(); container;
container = container->Container()) {
if (!container->FirstFragment().HasLocalBorderBoxProperties())
continue;
const FragmentData* container_fragment = &container->FirstFragment();
while (container_fragment->LogicalTopInFlowThread() <
logical_top_in_containing_flow_thread &&
container_fragment->NextFragment())
container_fragment = container_fragment->NextFragment();
if (container_fragment->LogicalTopInFlowThread() ==
logical_top_in_containing_flow_thread) {
// Found a matching fragment in an ancestor container. Use the
// container's content clip as the clip state.
found_clip = &container_fragment->ContentsClip();
break;
}
// We didn't find corresponding fragment in the container because the
// fragment fully overflows the container. If the container has overflow
// clip, then this fragment should be under |container_fragment|.
// This works only when the current fragment and the overflow clip are under
// the same flow thread. In other cases, we just leave it broken, which will
// be fixed by LayoutNG block fragments hopefully.
if (!crossed_flow_thread) {
if (const auto* container_properties =
container_fragment->PaintProperties()) {
if (const auto* overflow_clip = container_properties->OverflowClip()) {
context.logical_top_in_flow_thread =
container_fragment->LogicalTopInFlowThread();
found_clip = overflow_clip;
break;
}
}
}
if (container->IsLayoutFlowThread()) {
logical_top_in_containing_flow_thread =
FragmentLogicalTopInParentFlowThread(
To<LayoutFlowThread>(*container),
logical_top_in_containing_flow_thread);
crossed_flow_thread = true;
}
}
// We should always find a matching ancestor fragment in the above loop
// because logical_top_in_containing_flow_thread will be zero when we traverse
// across the top-level flow thread and it should match the first fragment of
// a non-fragmented ancestor container.
DCHECK(found_clip);
if (!crossed_flow_thread)
context.fragment_clip = absl::nullopt;
context.current.clip = found_clip;
if (object_.StyleRef().GetPosition() == EPosition::kAbsolute)
context.absolute_position.clip = found_clip;
else if (object_.StyleRef().GetPosition() == EPosition::kFixed)
context.fixed_position.clip = found_clip;
return context;
}
void PaintPropertyTreeBuilder::CreateFragmentContextsInFlowThread(
bool needs_paint_properties) {
DCHECK(!IsInNGFragmentTraversal());
// We need at least the fragments for all fragmented objects, which store
// their local border box properties and paint invalidation data (such
// as paint offset and visual rect) on each fragment.
PaintLayer* paint_layer = context_.painting_layer;
PaintLayer* enclosing_pagination_layer =
paint_layer->EnclosingPaginationLayer();
const auto& flow_thread =
To<LayoutFlowThread>(enclosing_pagination_layer->GetLayoutObject());
PhysicalRect object_bounding_box_in_flow_thread;
if (context_.repeating_table_section) {
// The object is a descendant of a repeating object. It should use the
// repeating bounding box to repeat in the same fragments as its
// repeating ancestor.
object_bounding_box_in_flow_thread =
context_.repeating_table_section_bounding_box;
} else {
object_bounding_box_in_flow_thread =
BoundingBoxInPaginationContainer(object_, *enclosing_pagination_layer);
if (IsRepeatingTableSection(object_)) {
context_.repeating_table_section =
&ToInterface<LayoutNGTableSectionInterface>(object_);
context_.repeating_table_section_bounding_box =
object_bounding_box_in_flow_thread;
}
}
FragmentData* current_fragment_data = nullptr;
FragmentainerIterator iterator(
flow_thread, object_bounding_box_in_flow_thread.ToLayoutRect());
bool fragments_changed = false;
HeapVector<PaintPropertyTreeBuilderFragmentContext, 1> new_fragment_contexts;
ClearCollectionScope<HeapVector<PaintPropertyTreeBuilderFragmentContext, 1>>
scope(&new_fragment_contexts);
for (; !iterator.AtEnd(); iterator.Advance()) {
auto pagination_offset =
PhysicalOffsetToBeNoop(iterator.PaginationOffset());
auto logical_top_in_flow_thread =
iterator.FragmentainerLogicalTopInFlowThread();
absl::optional<PhysicalRect> fragment_clip;
if (object_.HasLayer()) {
// 1. Compute clip in flow thread space.
fragment_clip = PhysicalRectToBeNoop(iterator.ClipRectInFlowThread());
// We skip empty clip fragments, since they can share the same logical top
// with the subsequent fragments. Since we skip drawing empty fragments
// anyway, it doesn't affect the paint output, but it allows us to use
// logical top to uniquely identify fragments in an object.
if (fragment_clip->IsEmpty())
continue;
// 2. Convert #1 to visual coordinates in the space of the flow thread.
fragment_clip->Move(pagination_offset);
// 3. Adjust #2 to visual coordinates in the containing "paint offset"
// space.
{
DCHECK(context_.fragments[0].current.paint_offset_root);
PhysicalOffset pagination_visual_offset =
VisualOffsetFromPaintOffsetRoot(context_.fragments[0],
enclosing_pagination_layer);
// Adjust for paint offset of the root, which may have a subpixel
// component. The paint offset root never has more than one fragment.
pagination_visual_offset +=
context_.fragments[0]
.current.paint_offset_root->FirstFragment()
.PaintOffset();
fragment_clip->Move(pagination_visual_offset);
}
}
// Match to parent fragments from the same containing flow thread.
auto fragment_context =
ContextForFragment(fragment_clip, logical_top_in_flow_thread);
// ContextForFragment may override logical_top_in_flow_thread.
logical_top_in_flow_thread = fragment_context.logical_top_in_flow_thread;
// Avoid fragment with duplicated overridden logical_top_in_flow_thread.
if (new_fragment_contexts.size() &&
new_fragment_contexts.back().logical_top_in_flow_thread ==
logical_top_in_flow_thread)
break;
new_fragment_contexts.push_back(fragment_context);
if (current_fragment_data) {
if (!current_fragment_data->NextFragment())
fragments_changed = true;
current_fragment_data = &current_fragment_data->EnsureNextFragment();
} else {
current_fragment_data = &object_.GetMutableForPainting().FirstFragment();
}
fragments_changed |= logical_top_in_flow_thread !=
current_fragment_data->LogicalTopInFlowThread();
if (!fragments_changed) {
const ClipPaintPropertyNode* old_fragment_clip = nullptr;
if (const auto* properties = current_fragment_data->PaintProperties())
old_fragment_clip = properties->FragmentClip();
const absl::optional<PhysicalRect>& new_fragment_clip =
new_fragment_contexts.back().fragment_clip;
fragments_changed = !!old_fragment_clip != !!new_fragment_clip ||
(old_fragment_clip && new_fragment_clip &&
old_fragment_clip->PaintClipRect() !=
ToSnappedClipRect(*new_fragment_clip));
}
InitFragmentPaintPropertiesForLegacy(
*current_fragment_data,
needs_paint_properties || new_fragment_contexts.back().fragment_clip,
pagination_offset, new_fragment_contexts.back());
}
if (!current_fragment_data) {
// This will be an empty fragment - get rid of it?
InitSingleFragmentFromParent(needs_paint_properties);
} else {
if (current_fragment_data->NextFragment())
fragments_changed = true;
current_fragment_data->ClearNextFragment();
context_.fragments = new_fragment_contexts;
}
// Need to update subtree paint properties for the changed fragments.
if (fragments_changed) {
object_.GetMutableForPainting().AddSubtreePaintPropertyUpdateReason(
SubtreePaintPropertyUpdateReason::kFragmentsChanged);
}
}
bool PaintPropertyTreeBuilder::ObjectIsRepeatingTableSectionInPagedMedia()
const {
if (!IsRepeatingTableSection(object_))
return false;
// The table section repeats in the pagination layer instead of paged media.
if (context_.painting_layer->EnclosingPaginationLayer())
return false;
if (!object_.View()->PageLogicalHeight())
return false;
// TODO(crbug.com/619094): Figure out the correct behavior for repeating
// objects in paged media with vertical writing modes.
if (!object_.View()->IsHorizontalWritingMode())
return false;
return true;
}
void PaintPropertyTreeBuilder::
CreateFragmentContextsForRepeatingFixedPosition() {
DCHECK(object_.IsFixedPositionObjectInPagedMedia());
LayoutView* view = object_.View();
auto page_height = view->PageLogicalHeight();
int page_count = ceilf(view->DocumentRect().Height() / page_height);
context_.fragments.resize(page_count);
if (auto* scrollable_area = view->GetScrollableArea()) {
context_.fragments[0].fixed_position.paint_offset.top -=
LayoutUnit(scrollable_area->ScrollPosition().y());
}
for (int page = 1; page < page_count; page++) {
context_.fragments[page] = context_.fragments[page - 1];
context_.fragments[page].fixed_position.paint_offset.top += page_height;
context_.fragments[page].logical_top_in_flow_thread += page_height;
}
}
void PaintPropertyTreeBuilder::
CreateFragmentContextsForRepeatingTableSectionInPagedMedia() {
DCHECK(ObjectIsRepeatingTableSectionInPagedMedia());
// The containing LayoutView serves as the virtual pagination container
// for repeating table section in paged media.
LayoutView* view = object_.View();
context_.repeating_table_section_bounding_box =
BoundingBoxInPaginationContainer(object_, *view->Layer());
// Convert the bounding box into the scrolling contents space.
if (auto* scrollable_area = view->GetScrollableArea()) {
context_.repeating_table_section_bounding_box.offset.top +=
LayoutUnit(scrollable_area->ScrollPosition().y());
}
auto page_height = view->PageLogicalHeight();
const auto& bounding_box = context_.repeating_table_section_bounding_box;
int first_page = floorf(bounding_box.Y() / page_height);
int last_page = ceilf(bounding_box.Bottom() / page_height) - 1;
if (first_page >= last_page)
return;
context_.fragments.resize(last_page - first_page + 1);
for (int page = first_page; page <= last_page; page++) {
if (page > first_page)
context_.fragments[page - first_page] = context_.fragments[0];
context_.fragments[page - first_page].logical_top_in_flow_thread =
page * page_height;
}
}
bool PaintPropertyTreeBuilder::IsRepeatingInPagedMedia() const {
return context_.is_repeating_fixed_position ||
(context_.repeating_table_section &&
!context_.painting_layer->EnclosingPaginationLayer());
}
void PaintPropertyTreeBuilder::CreateFragmentDataForRepeatingInPagedMedia(
bool needs_paint_properties) {
DCHECK(IsRepeatingInPagedMedia());
FragmentData* fragment_data = nullptr;
for (auto& fragment_context : context_.fragments) {
fragment_data = fragment_data
? &fragment_data->EnsureNextFragment()
: &object_.GetMutableForPainting().FirstFragment();
InitFragmentPaintPropertiesForLegacy(*fragment_data, needs_paint_properties,
PhysicalOffset(), fragment_context);
}
DCHECK(fragment_data);
fragment_data->ClearNextFragment();
}
void PaintPropertyTreeBuilder::UpdateFragments() {
bool needs_paint_properties =
#if !DCHECK_IS_ON()
// If DCHECK is not on, use fast path for text.
!object_.IsText() &&
#endif
(NeedsPaintOffsetTranslation(object_,
context_.direct_compositing_reasons) ||
NeedsStickyTranslation(object_) ||
NeedsAnchorScrollTranslation(object_) ||
NeedsTranslate(object_, context_.direct_compositing_reasons) ||
NeedsRotate(object_, context_.direct_compositing_reasons) ||
NeedsScale(object_, context_.direct_compositing_reasons) ||
NeedsOffset(object_, context_.direct_compositing_reasons) ||
NeedsTransform(object_, context_.direct_compositing_reasons) ||
NeedsEffectIgnoringClipPath(object_,
context_.direct_compositing_reasons) ||
NeedsClipPathClipOrMask(object_) ||
NeedsTransformForSVGChild(object_,
context_.direct_compositing_reasons) ||
NeedsFilter(object_, context_) || NeedsCssClip(object_) ||
NeedsInnerBorderRadiusClip(object_) || NeedsOverflowClip(object_) ||
NeedsPerspective(object_) || NeedsReplacedContentTransform(object_) ||
NeedsScrollOrScrollTranslation(object_,
context_.direct_compositing_reasons));
// If the object is a text, none of the above function should return true.
DCHECK(!needs_paint_properties || !object_.IsText());
// Need of fragmentation clip will be determined in CreateFragmentContexts().
if (IsInNGFragmentTraversal()) {
InitFragmentPaintPropertiesForNG(needs_paint_properties);
} else {
if (object_.IsFixedPositionObjectInPagedMedia()) {
// This flag applies to the object itself and descendants.
context_.is_repeating_fixed_position = true;
CreateFragmentContextsForRepeatingFixedPosition();
} else if (ObjectIsRepeatingTableSectionInPagedMedia()) {
context_.repeating_table_section =
&ToInterface<LayoutNGTableSectionInterface>(object_);
CreateFragmentContextsForRepeatingTableSectionInPagedMedia();
}
if (IsRepeatingInPagedMedia()) {
CreateFragmentDataForRepeatingInPagedMedia(needs_paint_properties);
} else if (context_.painting_layer->EnclosingPaginationLayer()) {
CreateFragmentContextsInFlowThread(needs_paint_properties);
} else {
InitSingleFragmentFromParent(needs_paint_properties);
context_.is_repeating_fixed_position = false;
context_.repeating_table_section = nullptr;
}
}
if (object_.IsSVGHiddenContainer()) {
// SVG resources are painted within one or more other locations in the
// SVG during paint, and hence have their own independent paint property
// trees, paint offset, etc.
context_.fragments.clear();
context_.fragments.Grow(1);
context_.has_svg_hidden_container_ancestor = true;
PaintPropertyTreeBuilderFragmentContext& fragment_context =
context_.fragments[0];
fragment_context.current.paint_offset_root =
fragment_context.absolute_position.paint_offset_root =
fragment_context.fixed_position.paint_offset_root = &object_;
object_.GetMutableForPainting().FirstFragment().ClearNextFragment();
}
if (object_.HasLayer()) {
To<LayoutBoxModelObject>(object_).Layer()->SetIsUnderSVGHiddenContainer(
context_.has_svg_hidden_container_ancestor);
}
if (!IsInNGFragmentTraversal())
UpdateRepeatingTableSectionPaintOffsetAdjustment();
}
bool PaintPropertyTreeBuilder::ObjectTypeMightNeedPaintProperties() const {
return !object_.IsText() && (object_.IsBoxModelObject() || object_.IsSVG());
}
bool PaintPropertyTreeBuilder::ObjectTypeMightNeedMultipleFragmentData() const {
return context_.painting_layer->EnclosingPaginationLayer() ||
context_.repeating_table_section ||
context_.is_repeating_fixed_position;
}
void PaintPropertyTreeBuilder::UpdatePaintingLayer() {
if (object_.HasLayer() &&
To<LayoutBoxModelObject>(object_).HasSelfPaintingLayer()) {
context_.painting_layer = To<LayoutBoxModelObject>(object_).Layer();
} else if (!IsInNGFragmentTraversal() &&
(object_.IsColumnSpanAll() ||
object_.IsFloatingWithNonContainingBlockParent())) {
// See LayoutObject::paintingLayer() for the special-cases of floating under
// inline and multicolumn.
context_.painting_layer = object_.PaintingLayer();
}
DCHECK(context_.painting_layer == object_.PaintingLayer());
}
void PaintPropertyTreeBuilder::UpdateForSelf() {
// These are not inherited from the parent context but calculated here.
context_.direct_compositing_reasons =
CompositingReasonFinder::DirectReasonsForPaintPropertiesExceptScrolling(
object_);
context_.was_main_thread_scrolling = false;
if (const auto* box = DynamicTo<LayoutBox>(object_)) {
if (auto* scrollable_area = box->GetScrollableArea()) {
scrollable_area->UpdateNeedsCompositedScrolling(
CompositingReasonFinder::ShouldForcePreferCompositingToLCDText(
object_, context_.direct_compositing_reasons));
context_.was_main_thread_scrolling =
scrollable_area->ShouldScrollOnMainThread();
context_.direct_compositing_reasons =
CompositingReasonFinder::DirectReasonsForPaintProperties(
object_, context_.direct_compositing_reasons);
}
}
context_.was_layout_shift_root =
IsLayoutShiftRoot(object_, object_.FirstFragment());
context_.old_scroll_offset = gfx::Vector2dF();
if (const auto* properties = object_.FirstFragment().PaintProperties()) {
if (const auto* old_scroll_translation = properties->ScrollTranslation()) {
DCHECK(context_.was_layout_shift_root);
context_.old_scroll_offset = old_scroll_translation->Translation2D();
}
}
UpdatePaintingLayer();
if (ObjectTypeMightNeedPaintProperties() ||
ObjectTypeMightNeedMultipleFragmentData()) {
UpdateFragments();
} else {
DCHECK_EQ(context_.direct_compositing_reasons, CompositingReason::kNone);
if (!IsInNGFragmentTraversal())
object_.GetMutableForPainting().FirstFragment().ClearNextFragment();
}
if (pre_paint_info_) {
DCHECK_EQ(context_.fragments.size(), 1u);
FragmentPaintPropertyTreeBuilder builder(object_, pre_paint_info_, context_,
context_.fragments[0],
*pre_paint_info_->fragment_data);
builder.UpdateForSelf();
properties_changed_.Merge(builder.PropertiesChanged());
} else {
auto* fragment_data = &object_.GetMutableForPainting().FirstFragment();
for (auto& fragment_context : context_.fragments) {
FragmentPaintPropertyTreeBuilder builder(
object_, /* pre_paint_info */ nullptr, context_, fragment_context,
*fragment_data);
builder.UpdateForSelf();
properties_changed_.Merge(builder.PropertiesChanged());
fragment_data = fragment_data->NextFragment();
}
DCHECK(!fragment_data);
}
object_.GetMutableForPainting()
.SetShouldAssumePaintOffsetTranslationForLayoutShiftTracking(false);
}
void PaintPropertyTreeBuilder::UpdateForChildren() {
if (!ObjectTypeMightNeedPaintProperties())
return;
FragmentData* fragment_data;
if (pre_paint_info_) {
DCHECK_EQ(context_.fragments.size(), 1u);
fragment_data = pre_paint_info_->fragment_data;
DCHECK(fragment_data);
} else {
fragment_data = &object_.GetMutableForPainting().FirstFragment();
}
// For now, only consider single fragment elements as possible isolation
// boundaries.
// TODO(crbug.com/890932): See if this is needed.
bool is_isolated = context_.fragments.size() == 1u;
for (auto& fragment_context : context_.fragments) {
FragmentPaintPropertyTreeBuilder builder(object_, pre_paint_info_, context_,
fragment_context, *fragment_data);
// The element establishes an isolation boundary if it has isolation nodes
// before and after updating the children. In other words, if it didn't have
// isolation nodes previously then we still want to do a subtree walk. If it
// now doesn't have isolation nodes, then of course it is also not isolated.
is_isolated &= builder.HasIsolationNodes();
builder.UpdateForChildren();
is_isolated &= builder.HasIsolationNodes();
properties_changed_.Merge(builder.PropertiesChanged());
fragment_data = fragment_data->NextFragment();
}
// With NG fragment traversal we were supplied with the right FragmentData by
// the caller, and we only ran one lap in the loop above. Whether or not there
// are more FragmentData objects following is irrelevant then.
DCHECK(pre_paint_info_ || !fragment_data);
if (object_.CanContainAbsolutePositionObjects())
context_.container_for_absolute_position = &object_;
if (object_.CanContainFixedPositionObjects())
context_.container_for_fixed_position = &object_;
if (properties_changed_.Max() >=
PaintPropertyChangeType::kNodeAddedOrRemoved ||
object_.SubtreePaintPropertyUpdateReasons() !=
static_cast<unsigned>(SubtreePaintPropertyUpdateReason::kNone)) {
// Force a piercing subtree update if the scroll tree hierarchy changes
// because the scroll tree does not have isolation nodes and non-piercing
// updates can fail to update scroll descendants.
if (properties_changed_.scroll_changed >=
PaintPropertyChangeType::kNodeAddedOrRemoved ||
AreSubtreeUpdateReasonsIsolationPiercing(
object_.SubtreePaintPropertyUpdateReasons())) {
context_.force_subtree_update_reasons |=
PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationPiercing;
} else {
context_.force_subtree_update_reasons |=
PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationBlocked;
}
}
if (is_isolated) {
context_.force_subtree_update_reasons &=
~PaintPropertyTreeBuilderContext::kSubtreeUpdateIsolationBlocked;
}
}
namespace {
PaintArtifactCompositorUpdateReason PACUpdateReasonForPaintPropertyChange(
PaintPropertyChangeType change) {
switch (change) {
case (PaintPropertyChangeType::kChangedOnlyNonRerasterValues):
return PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderPaintPropertyChangedOnlyNonRerasterValues;
case (PaintPropertyChangeType::kChangedOnlySimpleValues):
return PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderPaintPropertyChangedOnlySimpleValues;
case (PaintPropertyChangeType::kChangedOnlyValues):
return PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderPaintPropertyChangedOnlyValues;
case (PaintPropertyChangeType::kNodeAddedOrRemoved):
return PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderPaintPropertyAddedOrRemoved;
default:
// The other values for PaintPropertyChangeType should not cause a
// paint artifact compositor update.
NOTREACHED();
}
return PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderPaintPropertyChanged;
}
} // namespace
void PaintPropertyTreeBuilder::IssueInvalidationsAfterUpdate() {
// We need to update property tree states of paint chunks.
auto max_change = properties_changed_.Max();
if (max_change >= PaintPropertyChangeType::kNodeAddedOrRemoved) {
context_.painting_layer->SetNeedsRepaint();
if (object_.IsDocumentElement()) {
// View background painting depends on existence of the document element's
// paint properties (see callsite of ViewPainter::PaintRootGroup()).
// Invalidate view background display item clients.
// SetBackgroundNeedsFullPaintInvalidation() won't work here because we
// have already walked the LayoutView in PrePaintTreeWalk.
LayoutView* layout_view = object_.View();
layout_view->Layer()->SetNeedsRepaint();
auto reason = PaintInvalidationReason::kBackground;
static_cast<const DisplayItemClient*>(layout_view)->Invalidate(reason);
if (auto* scrollable_area = layout_view->GetScrollableArea()) {
scrollable_area->GetScrollingBackgroundDisplayItemClient().Invalidate(
reason);
}
}
}
if (max_change > PaintPropertyChangeType::kChangedOnlyCompositedValues) {
auto reason = PACUpdateReasonForPaintPropertyChange(max_change);
object_.GetFrameView()->SetPaintArtifactCompositorNeedsUpdate(reason);
}
if (auto* box = DynamicTo<LayoutBox>(object_)) {
if (auto* scrollable_area = box->GetScrollableArea()) {
if (context_.was_main_thread_scrolling !=
scrollable_area->ShouldScrollOnMainThread())
scrollable_area->MainThreadScrollingDidChange();
}
}
if (!RuntimeEnabledFeatures::ScrollUpdateOptimizationsEnabled()) {
if (const auto* properties = object_.FirstFragment().PaintProperties()) {
if (const auto* scroll_translation = properties->ScrollTranslation()) {
if (scroll_translation->Translation2D() != context_.old_scroll_offset) {
// Scrolling can change overlap relationship for elements fixed to an
// overflow: hidden view that programmatically scrolls via script.
// In this case the fixed transform doesn't have enough information to
// perform the expansion - there is no scroll node to describe the
// bounds of the scrollable content.
auto* frame_view = object_.GetFrameView();
if (frame_view->HasFixedPositionObjects() &&
!object_.View()->FirstFragment().PaintProperties()->Scroll()) {
frame_view->SetPaintArtifactCompositorNeedsUpdate(
PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBuilderHasFixedPositionObjects);
} else if (!object_.IsStackingContext() &&
To<LayoutBoxModelObject>(object_)
.Layer()
->HasSelfPaintingLayerDescendant()) {
// If the scroller is not a stacking context but contains stacked
// descendants, we need to update compositing because the stacked
// descendants may change overlap relationship with other stacked
// elements that are not contained by this scroller.
frame_view->SetPaintArtifactCompositorNeedsUpdate(
PaintArtifactCompositorUpdateReason::
kPaintPropertyTreeBulderNonStackingContextScroll);
}
}
}
}
}
CullRectUpdater::PaintPropertiesChanged(object_, properties_changed_);
}
} // namespace blink