1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_HWUI_SNAPSHOT_H
18 #define ANDROID_HWUI_SNAPSHOT_H
19 
20 #include <GLES2/gl2.h>
21 #include <GLES2/gl2ext.h>
22 
23 #include <utils/LinearAllocator.h>
24 #include <utils/RefBase.h>
25 #include <ui/Region.h>
26 
27 #include <SkRegion.h>
28 
29 #include "ClipArea.h"
30 #include "Layer.h"
31 #include "Matrix.h"
32 #include "Outline.h"
33 #include "Rect.h"
34 #include "utils/Macros.h"
35 
36 namespace android {
37 namespace uirenderer {
38 
39 /**
40  * Temporary structure holding information for a single outline clip.
41  *
42  * These structures are treated as immutable once created, and only exist for a single frame, which
43  * is why they may only be allocated with a LinearAllocator.
44  */
45 class RoundRectClipState {
46 public:
47     static void* operator new(size_t size) = delete;
new(size_t size,LinearAllocator & allocator)48     static void* operator new(size_t size, LinearAllocator& allocator) {
49         return allocator.alloc<RoundRectClipState>(size);
50     }
51 
areaRequiresRoundRectClip(const Rect & rect)52     bool areaRequiresRoundRectClip(const Rect& rect) const {
53         return rect.intersects(dangerRects[0])
54                 || rect.intersects(dangerRects[1])
55                 || rect.intersects(dangerRects[2])
56                 || rect.intersects(dangerRects[3]);
57     }
58 
59     bool highPriority;
60     Matrix4 matrix;
61     Rect dangerRects[4];
62     Rect innerRect;
63     float radius;
64 };
65 
66 // TODO: remove for HWUI_NEW_OPS
67 class ProjectionPathMask {
68 public:
69     static void* operator new(size_t size) = delete;
new(size_t size,LinearAllocator & allocator)70     static void* operator new(size_t size, LinearAllocator& allocator) {
71         return allocator.alloc<ProjectionPathMask>(size);
72     }
73 
74     const SkPath* projectionMask;
75     Matrix4 projectionMaskTransform;
76 };
77 
78 /**
79  * A snapshot holds information about the current state of the rendering
80  * surface. A snapshot is usually created whenever the user calls save()
81  * and discarded when the user calls restore(). Once a snapshot is created,
82  * it can hold information for deferred rendering.
83  *
84  * Each snapshot has a link to a previous snapshot, indicating the previous
85  * state of the renderer.
86  */
87 class Snapshot {
88 public:
89 
90     Snapshot();
91     Snapshot(Snapshot* s, int saveFlags);
92 
93     /**
94      * Various flags set on ::flags.
95      */
96     enum Flags {
97         /**
98          * Indicates that the clip region was modified. When this
99          * snapshot is restored so must the clip.
100          */
101         kFlagClipSet = 0x1,
102         /**
103          * Indicates that this snapshot was created when saving
104          * a new layer.
105          */
106         kFlagIsLayer = 0x2,
107         /**
108          * Indicates that this snapshot is a special type of layer
109          * backed by an FBO. This flag only makes sense when the
110          * flag kFlagIsLayer is also set.
111          *
112          * Viewport has been modified to fit the new Fbo, and must be
113          * restored when this snapshot is restored.
114          */
115         kFlagIsFboLayer = 0x4,
116         /**
117          * Indicates that this snapshot or an ancestor snapshot is
118          * an FBO layer.
119          */
120         kFlagFboTarget = 0x8, // TODO: remove for HWUI_NEW_OPS
121     };
122 
123     /**
124      * Modifies the current clip with the new clip rectangle and
125      * the specified operation. The specified rectangle is transformed
126      * by this snapshot's trasnformation.
127      */
128     void clip(const Rect& localClip, SkRegion::Op op);
129 
130     /**
131      * Modifies the current clip with the new clip rectangle and
132      * the specified operation. The specified rectangle is considered
133      * already transformed.
134      */
135     void clipTransformed(const Rect& r, SkRegion::Op op = SkRegion::kIntersect_Op);
136 
137     /**
138      * Modifies the current clip with the specified region and operation.
139      * The specified region is considered already transformed.
140      */
141     void clipRegionTransformed(const SkRegion& region, SkRegion::Op op);
142 
143     /**
144      * Modifies the current clip with the specified path and operation.
145      */
146     void clipPath(const SkPath& path, SkRegion::Op op);
147 
148     /**
149      * Sets the current clip.
150      */
151     void setClip(float left, float top, float right, float bottom);
152 
153     /**
154      * Returns the current clip in local coordinates. The clip rect is
155      * transformed by the inverse transform matrix.
156      */
157     ANDROID_API const Rect& getLocalClip();
158 
159     /**
160      * Returns the current clip in render target coordinates.
161      */
getRenderTargetClip()162     const Rect& getRenderTargetClip() const { return mClipArea->getClipRect(); }
163 
164     /*
165      * Accessor functions so that the clip area can stay private
166      */
clipIsEmpty()167     bool clipIsEmpty() const { return mClipArea->isEmpty(); }
getClipRegion()168     const SkRegion& getClipRegion() const { return mClipArea->getClipRegion(); }
clipIsSimple()169     bool clipIsSimple() const { return mClipArea->isSimple(); }
getClipArea()170     const ClipArea& getClipArea() const { return *mClipArea; }
mutateClipArea()171     ClipArea& mutateClipArea() { return *mClipArea; }
172 
173     WARN_UNUSED_RESULT const ClipBase* serializeIntersectedClip(LinearAllocator& allocator,
174             const ClipBase* recordedClip, const Matrix4& recordedClipTransform);
175     void applyClip(const ClipBase* clip, const Matrix4& transform);
176 
177     /**
178      * Resets the clip to the specified rect.
179      */
180     void resetClip(float left, float top, float right, float bottom);
181 
182     /**
183      * Resets the current transform to a pure 3D translation.
184      */
185     void resetTransform(float x, float y, float z);
186 
initializeViewport(int width,int height)187     void initializeViewport(int width, int height) {
188         mViewportData.initialize(width, height);
189         mClipAreaRoot.setViewportDimensions(width, height);
190     }
191 
getViewportWidth()192     int getViewportWidth() const { return mViewportData.mWidth; }
getViewportHeight()193     int getViewportHeight() const { return mViewportData.mHeight; }
getOrthoMatrix()194     const Matrix4& getOrthoMatrix() const { return mViewportData.mOrthoMatrix; }
195 
getRelativeLightCenter()196     const Vector3& getRelativeLightCenter() const { return mRelativeLightCenter; }
setRelativeLightCenter(const Vector3 & lightCenter)197     void setRelativeLightCenter(const Vector3& lightCenter) { mRelativeLightCenter = lightCenter; }
198 
199     /**
200      * Sets (and replaces) the current clipping outline
201      *
202      * If the current round rect clip is high priority, the incoming clip is ignored.
203      */
204     void setClippingRoundRect(LinearAllocator& allocator, const Rect& bounds,
205             float radius, bool highPriority);
206 
207     /**
208      * Sets (and replaces) the current projection mask
209      */
210     void setProjectionPathMask(LinearAllocator& allocator, const SkPath* path);
211 
212     /**
213      * Indicates whether this snapshot should be ignored. A snapshot
214      * is typically ignored if its layer is invisible or empty.
215      */
216     bool isIgnored() const;
217 
218     /**
219      * Indicates whether the current transform has perspective components.
220      */
221     bool hasPerspectiveTransform() const;
222 
223     /**
224      * Fills outTransform with the current, total transform to screen space,
225      * across layer boundaries.
226      */
227     // TODO: remove for HWUI_NEW_OPS
228     void buildScreenSpaceTransform(Matrix4* outTransform) const;
229 
230     /**
231      * Dirty flags.
232      */
233     int flags;
234 
235     /**
236      * Previous snapshot.
237      */
238     Snapshot* previous;
239 
240     /**
241      * A pointer to the currently active layer.
242      *
243      * This snapshot does not own the layer, this pointer must not be freed.
244      */
245     Layer* layer;
246 
247     /**
248      * Target FBO used for rendering. Set to 0 when rendering directly
249      * into the framebuffer.
250      */
251     GLuint fbo;
252 
253     /**
254      * Indicates that this snapshot is invisible and nothing should be drawn
255      * inside it. This flag is set only when the layer clips drawing to its
256      * bounds and is passed to subsequent snapshots.
257      */
258     bool invisible;
259 
260     /**
261      * If set to true, the layer will not be composited. This is similar to
262      * invisible but this flag is not passed to subsequent snapshots.
263      */
264     bool empty;
265 
266     /**
267      * Local transformation. Holds the current translation, scale and
268      * rotation values.
269      *
270      * This is a reference to a matrix owned by this snapshot or another
271      *  snapshot. This pointer must not be freed. See ::mTransformRoot.
272      */
273     mat4* transform;
274 
275     /**
276      * The ancestor layer's dirty region.
277      *
278      * This is a reference to a region owned by a layer. This pointer must
279      * not be freed.
280      */
281     Region* region;
282 
283     /**
284      * Current alpha value. This value is 1 by default, but may be set by a DisplayList which
285      * has translucent rendering in a non-overlapping View. This value will be used by
286      * the renderer to set the alpha in the current color being used for ensuing drawing
287      * operations. The value is inherited by child snapshots because the same value should
288      * be applied to descendants of the current DisplayList (for example, a TextView contains
289      * the base alpha value which should be applied to the child DisplayLists used for drawing
290      * the actual text).
291      */
292     float alpha;
293 
294     /**
295      * Current clipping round rect.
296      *
297      * Points to data not owned by the snapshot, and may only be replaced by subsequent RR clips,
298      * never modified.
299      */
300     const RoundRectClipState* roundRectClipState;
301 
302     /**
303      * Current projection masking path - used exclusively to mask projected, tessellated circles.
304      */
305 #if HWUI_NEW_OPS
306     const SkPath* projectionPathMask;
307 #else
308     const ProjectionPathMask* projectionPathMask;
309 #endif
310 
311     void dump() const;
312 
313 private:
314     struct ViewportData {
ViewportDataViewportData315         ViewportData() : mWidth(0), mHeight(0) {}
initializeViewportData316         void initialize(int width, int height) {
317             mWidth = width;
318             mHeight = height;
319             mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
320         }
321 
322         /*
323          * Width and height of current viewport.
324          *
325          * The viewport is always defined to be (0, 0, width, height).
326          */
327         int mWidth;
328         int mHeight;
329         /**
330          * Contains the current orthographic, projection matrix.
331          */
332         mat4 mOrthoMatrix;
333     };
334 
335     mat4 mTransformRoot;
336 
337     ClipArea mClipAreaRoot;
338     ClipArea* mClipArea;
339     Rect mLocalClip;
340 
341     ViewportData mViewportData;
342     Vector3 mRelativeLightCenter;
343 
344 }; // class Snapshot
345 
346 }; // namespace uirenderer
347 }; // namespace android
348 
349 #endif // ANDROID_HWUI_SNAPSHOT_H
350