blob: 54e554719e4034256bd71c859cbb0e9f08dcf59c [file] [log] [blame]
// Copyright 2016 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 "base/containers/stack_container.h"
#include "base/optional.h"
#include "cc/cc_export.h"
#include "cc/trees/clip_expander.h"
#include "cc/trees/property_tree.h"
#include "ui/gfx/geometry/rect_f.h"
namespace base {
namespace trace_event {
class TracedValue;
} // namespace trace_event
} // namespace base
namespace cc {
struct CC_EXPORT ClipNode {
ClipNode(const ClipNode& other);
ClipNode& operator=(const ClipNode& other);
// The node index of this node in the clip tree node vector.
int id;
// The node index of the parent node in the clip tree node vector.
int parent_id;
enum class ClipType {
// The node contributes a new clip (that is, |clip| needs to be applied).
// This node represents a space expansion. When computing visible rects,
// the accumulated clip inherited by this node gets expanded. Similarly,
// when mapping a rect in descendant space to the rect in ancestor space
// that depends on the descendant rect's contents, this node expands the
// descendant rect. This is used for effects like pixel-moving filters,
// where clipped-out content can affect visible output.
ClipType clip_type;
// The clip rect that this node contributes, expressed in the space of its
// transform node.
gfx::RectF clip;
// Each element of this cache stores the accumulated clip from this clip
// node to a particular target. The number of cached clip rects required
// per node is roughly proportional to the number of render targets a
// given clip rect participates in. On many pages with only a root
// render target, the number of cached clip rects per node is 1.
// Any more than 3, and this will overflow rects onto the heap, so this
// number is a tradeoff of ClipNode size on average and access speed.
mutable base::StackVector<ClipRectData, 3> cached_clip_rects;
// This rect accumulates all clips from this node to the root in screen space.
// It is used in the computation of layer's visible rect.
gfx::RectF cached_accumulated_rect_in_screen_space;
// For nodes that expand, this represents the amount of expansion.
base::Optional<ClipExpander> clip_expander;
// The id of the transform node that defines the clip node's local space.
int transform_id;
bool operator==(const ClipNode& other) const;
void AsValueInto(base::trace_event::TracedValue* value) const;
} // namespace cc