| // 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. |
| |
| #ifndef CC_TREES_CLIP_NODE_H_ |
| #define CC_TREES_CLIP_NODE_H_ |
| |
| #include "base/containers/stack_container.h" |
| #include "base/optional.h" |
| #include "cc/cc_export.h" |
| #include "cc/trees/clip_expander.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(); |
| ClipNode(const ClipNode& other); |
| |
| ClipNode& operator=(const ClipNode& other); |
| |
| ~ClipNode(); |
| |
| // 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). |
| APPLIES_LOCAL_CLIP, |
| |
| // 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. |
| EXPANDS_CLIP |
| }; |
| |
| 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 |
| |
| #endif // CC_TREES_CLIP_NODE_H_ |