Snapshot.cpp revision 0baaac5e9adf3ee280ae1239e2e58754a9d2b099 
1/*
2 * Copyright (C) 2012 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#include "Snapshot.h"
18
19#include <SkCanvas.h>
20
21namespace android {
22namespace uirenderer {
23
24///////////////////////////////////////////////////////////////////////////////
25// Constructors
26///////////////////////////////////////////////////////////////////////////////
27
28Snapshot::Snapshot(): flags(0), previous(NULL), layer(NULL), fbo(0),
29        invisible(false), empty(false), alpha(1.0f) {
30
31    transform = &mTransformRoot;
32    clipRect = &mClipRectRoot;
33    region = NULL;
34    clipRegion = NULL;
35}
36
37/**
38 * Copies the specified snapshot/ The specified snapshot is stored as
39 * the previous snapshot.
40 */
41Snapshot::Snapshot(const sp<Snapshot>& s, int saveFlags):
42        flags(0), previous(s), layer(NULL), fbo(s->fbo),
43        invisible(s->invisible), empty(false),
44        viewport(s->viewport), height(s->height), alpha(s->alpha) {
45
46    clipRegion = NULL;
47
48    if (saveFlags & SkCanvas::kMatrix_SaveFlag) {
49        mTransformRoot.load(*s->transform);
50        transform = &mTransformRoot;
51    } else {
52        transform = s->transform;
53    }
54
55    if (saveFlags & SkCanvas::kClip_SaveFlag) {
56        mClipRectRoot.set(*s->clipRect);
57        clipRect = &mClipRectRoot;
58#if STENCIL_BUFFER_SIZE
59        if (s->clipRegion) {
60            mClipRegionRoot.op(*s->clipRegion, SkRegion::kUnion_Op);
61            clipRegion = &mClipRegionRoot;
62        }
63#endif
64    } else {
65        clipRect = s->clipRect;
66#if STENCIL_BUFFER_SIZE
67        clipRegion = s->clipRegion;
68#endif
69    }
70
71    if (s->flags & Snapshot::kFlagFboTarget) {
72        flags |= Snapshot::kFlagFboTarget;
73        region = s->region;
74    } else {
75        region = NULL;
76    }
77}
78
79///////////////////////////////////////////////////////////////////////////////
80// Clipping
81///////////////////////////////////////////////////////////////////////////////
82
83void Snapshot::ensureClipRegion() {
84#if STENCIL_BUFFER_SIZE
85    if (!clipRegion) {
86        clipRegion = &mClipRegionRoot;
87        clipRegion->setRect(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
88    }
89#endif
90}
91
92void Snapshot::copyClipRectFromRegion() {
93#if STENCIL_BUFFER_SIZE
94    if (!clipRegion->isEmpty()) {
95        const SkIRect& bounds = clipRegion->getBounds();
96        clipRect->set(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom);
97
98        if (clipRegion->isRect()) {
99            clipRegion->setEmpty();
100            clipRegion = NULL;
101        }
102    } else {
103        clipRect->setEmpty();
104        clipRegion = NULL;
105    }
106#endif
107}
108
109bool Snapshot::clipRegionOp(float left, float top, float right, float bottom, SkRegion::Op op) {
110#if STENCIL_BUFFER_SIZE
111    SkIRect tmp;
112    tmp.set(left, top, right, bottom);
113    clipRegion->op(tmp, op);
114    copyClipRectFromRegion();
115    return true;
116#else
117    return false;
118#endif
119}
120
121bool Snapshot::clip(float left, float top, float right, float bottom, SkRegion::Op op) {
122    Rect r(left, top, right, bottom);
123    transform->mapRect(r);
124    return clipTransformed(r, op);
125}
126
127bool Snapshot::clipTransformed(const Rect& r, SkRegion::Op op) {
128    bool clipped = false;
129
130    switch (op) {
131        case SkRegion::kIntersect_Op: {
132            if (CC_UNLIKELY(clipRegion)) {
133                clipped = clipRegionOp(r.left, r.top, r.right, r.bottom, SkRegion::kIntersect_Op);
134            } else {
135                clipped = clipRect->intersect(r);
136                if (!clipped) {
137                    clipRect->setEmpty();
138                    clipped = true;
139                }
140            }
141            break;
142        }
143        case SkRegion::kUnion_Op: {
144            if (CC_UNLIKELY(clipRegion)) {
145                clipped = clipRegionOp(r.left, r.top, r.right, r.bottom, SkRegion::kUnion_Op);
146            } else {
147                clipped = clipRect->unionWith(r);
148            }
149            break;
150        }
151        case SkRegion::kReplace_Op: {
152            setClip(r.left, r.top, r.right, r.bottom);
153            clipped = true;
154            break;
155        }
156        default: {
157            ensureClipRegion();
158            clipped = clipRegionOp(r.left, r.top, r.right, r.bottom, op);
159            break;
160        }
161    }
162
163    if (clipped) {
164        flags |= Snapshot::kFlagClipSet;
165    }
166
167    return clipped;
168}
169
170void Snapshot::setClip(float left, float top, float right, float bottom) {
171    clipRect->set(left, top, right, bottom);
172#if STENCIL_BUFFER_SIZE
173    if (clipRegion) {
174        clipRegion->setEmpty();
175        clipRegion = NULL;
176    }
177#endif
178    flags |= Snapshot::kFlagClipSet;
179}
180
181const Rect& Snapshot::getLocalClip() {
182    mat4 inverse;
183    inverse.loadInverse(*transform);
184
185    mLocalClip.set(*clipRect);
186    inverse.mapRect(mLocalClip);
187
188    return mLocalClip;
189}
190
191void Snapshot::resetClip(float left, float top, float right, float bottom) {
192    clipRect = &mClipRectRoot;
193    setClip(left, top, right, bottom);
194}
195
196///////////////////////////////////////////////////////////////////////////////
197// Transforms
198///////////////////////////////////////////////////////////////////////////////
199
200void Snapshot::resetTransform(float x, float y, float z) {
201    transform = &mTransformRoot;
202    transform->loadTranslate(x, y, z);
203}
204
205///////////////////////////////////////////////////////////////////////////////
206// Queries
207///////////////////////////////////////////////////////////////////////////////
208
209bool Snapshot::isIgnored() const {
210    return invisible || empty;
211}
212
213}; // namespace uirenderer
214}; // namespace android
215