1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef CC_TREES_PROPERTY_TREE_H_
6 #define CC_TREES_PROPERTY_TREE_H_
10 #include "base/basictypes.h"
11 #include "cc/base/cc_export.h"
12 #include "ui/gfx/geometry/rect.h"
13 #include "ui/gfx/geometry/scroll_offset.h"
14 #include "ui/gfx/transform.h"
19 struct CC_EXPORT TreeNode
{
20 TreeNode() : id(-1), parent_id(-1), owner_id(-1), data() {}
27 struct CC_EXPORT TransformNodeData
{
31 // The local transform information is combined to form to_parent (ignoring
32 // snapping) as follows:
34 // to_parent = M_post_local * T_scroll * M_local * M_pre_local.
36 // The pre/post may seem odd when read LTR, but we multiply our points from
37 // the right, so the pre_local matrix affects the result "first". This lines
38 // up with the notions of pre/post used in skia and gfx::Transform.
40 // TODO(vollick): The values labeled with "will be moved..." take up a lot of
41 // space, but are only necessary for animated or scrolled nodes (otherwise
42 // we'll just use the baked to_parent). These values will be ultimately stored
43 // directly on the transform/scroll display list items when that's possible,
44 // or potentially in a scroll tree.
46 // TODO(vollick): will be moved when accelerated effects are implemented.
47 gfx::Transform pre_local
;
49 gfx::Transform post_local
;
51 gfx::Transform to_parent
;
53 gfx::Transform to_target
;
54 gfx::Transform from_target
;
56 gfx::Transform to_screen
;
57 gfx::Transform from_screen
;
60 // This id is used for all content that draws into a render surface associated
61 // with this transform node.
62 int content_target_id
;
64 // This is the node with respect to which source_offset is defined. This will
65 // not be needed once layerization moves to cc, but is needed in order to
66 // efficiently update the transform tree for changes to position in the layer
70 // TODO(vollick): will be moved when accelerated effects are implemented.
71 bool needs_local_transform_update
: 1;
73 bool is_invertible
: 1;
74 bool ancestors_are_invertible
: 1;
77 bool to_screen_is_animated
: 1;
79 // Flattening, when needed, is only applied to a node's inherited transform,
80 // never to its local transform.
81 bool flattens_inherited_transform
: 1;
83 // This is true if the to_parent transform at every node on the path to the
85 bool node_and_ancestors_are_flat
: 1;
87 // This is needed to know if a layer can use lcd text.
88 bool node_and_ancestors_have_only_integer_translation
: 1;
92 bool needs_sublayer_scale
: 1;
94 // These are used to position nodes wrt the right or bottom of the inner or
96 bool affected_by_inner_viewport_bounds_delta_x
: 1;
97 bool affected_by_inner_viewport_bounds_delta_y
: 1;
98 bool affected_by_outer_viewport_bounds_delta_x
: 1;
99 bool affected_by_outer_viewport_bounds_delta_y
: 1;
101 // This is used as a fallback when we either cannot adjust raster scale or if
102 // the raster scale cannot be extracted from the screen space transform.
103 float layer_scale_factor
;
105 // TODO(vollick): will be moved when accelerated effects are implemented.
106 float post_local_scale_factor
;
108 gfx::Vector2dF sublayer_scale
;
110 // TODO(vollick): will be moved when accelerated effects are implemented.
111 gfx::ScrollOffset scroll_offset
;
113 // We scroll snap where possible, but this has an effect on scroll
114 // compensation: the snap is yet more scrolling that must be compensated for.
115 // This value stores the snapped amount for this purpose.
116 gfx::Vector2dF scroll_snap
;
118 // TODO(vollick): will be moved when accelerated effects are implemented.
119 gfx::Vector2dF source_offset
;
120 gfx::Vector2dF source_to_parent
;
122 void set_to_parent(const gfx::Transform
& transform
) {
123 to_parent
= transform
;
124 is_invertible
= to_parent
.IsInvertible();
127 void update_pre_local_transform(const gfx::Point3F
& transform_origin
);
129 void update_post_local_transform(const gfx::PointF
& position
,
130 const gfx::Point3F
& transform_origin
);
133 typedef TreeNode
<TransformNodeData
> TransformNode
;
135 struct CC_EXPORT ClipNodeData
{
139 gfx::RectF combined_clip
;
142 // This value is true for clip nodes created by layers that do not apply any
143 // clip themselves, but own a render surface that inherits the parent
144 // target space clip.
145 bool inherit_parent_target_space_clip
;
146 bool requires_tight_clip_rect
;
149 typedef TreeNode
<ClipNodeData
> ClipNode
;
151 struct CC_EXPORT OpacityNodeData
{
155 float screen_space_opacity
;
158 typedef TreeNode
<OpacityNodeData
> OpacityNode
;
160 template <typename T
>
161 class CC_EXPORT PropertyTree
{
164 virtual ~PropertyTree();
166 int Insert(const T
& tree_node
, int parent_id
);
169 // TODO(vollick): remove this.
170 CHECK(i
< static_cast<int>(nodes_
.size()));
171 return i
> -1 ? &nodes_
[i
] : nullptr;
173 const T
* Node(int i
) const {
174 // TODO(vollick): remove this.
175 CHECK(i
< static_cast<int>(nodes_
.size()));
176 return i
> -1 ? &nodes_
[i
] : nullptr;
179 T
* parent(const T
* t
) { return Node(t
->parent_id
); }
180 const T
* parent(const T
* t
) const { return Node(t
->parent_id
); }
182 T
* back() { return size() ? &nodes_
[nodes_
.size() - 1] : nullptr; }
183 const T
* back() const {
184 return size() ? &nodes_
[nodes_
.size() - 1] : nullptr;
187 virtual void clear();
188 size_t size() const { return nodes_
.size(); }
190 void set_needs_update(bool needs_update
) { needs_update_
= needs_update
; }
191 bool needs_update() const { return needs_update_
; }
194 // Copy and assign are permitted. This is how we do tree sync.
195 std::vector
<T
> nodes_
;
200 class CC_EXPORT TransformTree final
: public PropertyTree
<TransformNode
> {
203 ~TransformTree() override
;
205 void clear() override
;
207 // Computes the change of basis transform from node |source_id| to |dest_id|.
208 // The function returns false iff the inverse of a singular transform was
209 // used (and the result should, therefore, not be trusted). Transforms may
210 // be computed between any pair of nodes that have an ancestor/descendant
211 // relationship. Transforms between other pairs of nodes may only be computed
212 // if the following condition holds: let id1 the larger id and let id2 be the
213 // other id; then the nearest ancestor of node id1 whose id is smaller than
214 // id2 is the lowest common ancestor of the pair of nodes, and the transform
215 // from this lowest common ancestor to node id2 is only a 2d translation.
216 bool ComputeTransform(int source_id
,
218 gfx::Transform
* transform
) const;
220 // Computes the change of basis transform from node |source_id| to |dest_id|,
221 // including any sublayer scale at |dest_id|. The function returns false iff
222 // the inverse of a singular transform was used (and the result should,
223 // therefore, not be trusted).
224 bool ComputeTransformWithDestinationSublayerScale(
227 gfx::Transform
* transform
) const;
229 // Computes the change of basis transform from node |source_id| to |dest_id|,
230 // including any sublayer scale at |source_id|. The function returns false
231 // iff the inverse of a singular transform was used (and the result should,
232 // therefore, not be trusted).
233 bool ComputeTransformWithSourceSublayerScale(int source_id
,
235 gfx::Transform
* transform
) const;
237 // Returns true iff the nodes indexed by |source_id| and |dest_id| are 2D axis
238 // aligned with respect to one another.
239 bool Are2DAxisAligned(int source_id
, int dest_id
) const;
241 // Updates the parent, target, and screen space transforms and snapping.
242 void UpdateTransforms(int id
);
244 // A TransformNode's source_to_parent value is used to account for the fact
245 // that fixed-position layers are positioned by Blink wrt to their layer tree
246 // parent (their "source"), but are parented in the transform tree by their
247 // fixed-position container. This value needs to be updated on main-thread
248 // property trees (for position changes initiated by Blink), but not on the
249 // compositor thread (since the offset from a node corresponding to a
250 // fixed-position layer to its fixed-position container is unaffected by
251 // compositor-driven effects).
252 void set_source_to_parent_updates_allowed(bool allowed
) {
253 source_to_parent_updates_allowed_
= allowed
;
255 bool source_to_parent_updates_allowed() const {
256 return source_to_parent_updates_allowed_
;
259 void SetInnerViewportBoundsDelta(gfx::Vector2dF bounds_delta
);
260 gfx::Vector2dF
inner_viewport_bounds_delta() const {
261 return inner_viewport_bounds_delta_
;
264 void SetOuterViewportBoundsDelta(gfx::Vector2dF bounds_delta
);
265 gfx::Vector2dF
outer_viewport_bounds_delta() const {
266 return outer_viewport_bounds_delta_
;
269 void AddNodeAffectedByInnerViewportBoundsDelta(int node_id
);
270 void AddNodeAffectedByOuterViewportBoundsDelta(int node_id
);
272 bool HasNodesAffectedByInnerViewportBoundsDelta() const;
273 bool HasNodesAffectedByOuterViewportBoundsDelta() const;
276 // Returns true iff the node at |desc_id| is a descendant of the node at
278 bool IsDescendant(int desc_id
, int anc_id
) const;
280 // Computes the combined transform between |source_id| and |dest_id| and
281 // returns false if the inverse of a singular transform was used. These two
282 // nodes must be on the same ancestor chain.
283 bool CombineTransformsBetween(int source_id
,
285 gfx::Transform
* transform
) const;
287 // Computes the combined inverse transform between |source_id| and |dest_id|
288 // and returns false if the inverse of a singular transform was used. These
289 // two nodes must be on the same ancestor chain.
290 bool CombineInversesBetween(int source_id
,
292 gfx::Transform
* transform
) const;
294 void UpdateLocalTransform(TransformNode
* node
);
295 void UpdateScreenSpaceTransform(TransformNode
* node
,
296 TransformNode
* parent_node
,
297 TransformNode
* target_node
);
298 void UpdateSublayerScale(TransformNode
* node
);
299 void UpdateTargetSpaceTransform(TransformNode
* node
,
300 TransformNode
* target_node
);
301 void UpdateIsAnimated(TransformNode
* node
, TransformNode
* parent_node
);
302 void UpdateSnapping(TransformNode
* node
);
303 void UpdateNodeAndAncestorsHaveIntegerTranslations(
305 TransformNode
* parent_node
);
306 bool NeedsSourceToParentUpdate(TransformNode
* node
);
308 bool source_to_parent_updates_allowed_
;
309 gfx::Vector2dF inner_viewport_bounds_delta_
;
310 gfx::Vector2dF outer_viewport_bounds_delta_
;
311 std::vector
<int> nodes_affected_by_inner_viewport_bounds_delta_
;
312 std::vector
<int> nodes_affected_by_outer_viewport_bounds_delta_
;
315 class CC_EXPORT ClipTree final
: public PropertyTree
<ClipNode
> {};
317 class CC_EXPORT OpacityTree final
: public PropertyTree
<OpacityNode
> {
319 void UpdateOpacities(int id
);
322 class CC_EXPORT PropertyTrees final
{
326 TransformTree transform_tree
;
327 OpacityTree opacity_tree
;
335 #endif // CC_TREES_PROPERTY_TREE_H_