Snapshot.cpp revision b98a016c6769b9e80d392df22fe77a2fca048d9f 
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 = &mClipRegionRoot;
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(s->layer), fbo(s->fbo),
43        invisible(s->invisible), empty(false),
44        viewport(s->viewport), height(s->height), alpha(s->alpha) {
45
46    if (saveFlags & SkCanvas::kMatrix_SaveFlag) {
47        mTransformRoot.load(*s->transform);
48        transform = &mTransformRoot;
49    } else {
50        transform = s->transform;
51    }
52
53    if (saveFlags & SkCanvas::kClip_SaveFlag) {
54        mClipRectRoot.set(*s->clipRect);
55        clipRect = &mClipRectRoot;
56        if (!s->clipRegion->isEmpty()) {
57            mClipRegionRoot.op(*s->clipRegion, SkRegion::kUnion_Op);
58        }
59        clipRegion = &mClipRegionRoot;
60    } else {
61        clipRect = s->clipRect;
62        clipRegion = s->clipRegion;
63    }
64
65    if (s->flags & Snapshot::kFlagFboTarget) {
66        flags |= Snapshot::kFlagFboTarget;
67        region = s->region;
68    } else {
69        region = NULL;
70    }
71}
72
73///////////////////////////////////////////////////////////////////////////////
74// Clipping
75///////////////////////////////////////////////////////////////////////////////
76
77void Snapshot::ensureClipRegion() {
78    if (clipRegion->isEmpty()) {
79        clipRegion->setRect(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
80    }
81}
82
83void Snapshot::copyClipRectFromRegion() {
84    if (!clipRegion->isEmpty()) {
85        const SkIRect& bounds = clipRegion->getBounds();
86        clipRect->set(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom);
87
88        if (clipRegion->isRect()) {
89            clipRegion->setEmpty();
90        }
91    } else {
92        clipRect->setEmpty();
93    }
94}
95
96bool Snapshot::clipRegionOp(float left, float top, float right, float bottom, SkRegion::Op op) {
97    SkIRect tmp;
98    tmp.set(left, top, right, bottom);
99    clipRegion->op(tmp, op);
100    copyClipRectFromRegion();
101    return true;
102}
103
104bool Snapshot::clipRegionTransformed(const SkRegion& region, SkRegion::Op op) {
105    ensureClipRegion();
106    clipRegion->op(region, op);
107    copyClipRectFromRegion();
108    flags |= Snapshot::kFlagClipSet;
109    return true;
110}
111
112bool Snapshot::clip(float left, float top, float right, float bottom, SkRegion::Op op) {
113    Rect r(left, top, right, bottom);
114    transform->mapRect(r);
115    return clipTransformed(r, op);
116}
117
118bool Snapshot::clipTransformed(const Rect& r, SkRegion::Op op) {
119    bool clipped = false;
120
121    switch (op) {
122        case SkRegion::kIntersect_Op: {
123            if (CC_UNLIKELY(!clipRegion->isEmpty())) {
124                ensureClipRegion();
125                clipped = clipRegionOp(r.left, r.top, r.right, r.bottom, SkRegion::kIntersect_Op);
126            } else {
127                clipped = clipRect->intersect(r);
128                if (!clipped) {
129                    clipRect->setEmpty();
130                    clipped = true;
131                }
132            }
133            break;
134        }
135        case SkRegion::kReplace_Op: {
136            setClip(r.left, r.top, r.right, r.bottom);
137            clipped = true;
138            break;
139        }
140        default: {
141            ensureClipRegion();
142            clipped = clipRegionOp(r.left, r.top, r.right, r.bottom, op);
143            break;
144        }
145    }
146
147    if (clipped) {
148        flags |= Snapshot::kFlagClipSet;
149    }
150
151    return clipped;
152}
153
154void Snapshot::setClip(float left, float top, float right, float bottom) {
155    clipRect->set(left, top, right, bottom);
156    if (!clipRegion->isEmpty()) {
157        clipRegion->setEmpty();
158    }
159    flags |= Snapshot::kFlagClipSet;
160}
161
162bool Snapshot::hasPerspectiveTransform() const {
163    return transform->isPerspective();
164}
165
166const Rect& Snapshot::getLocalClip() {
167    mat4 inverse;
168    inverse.loadInverse(*transform);
169
170    mLocalClip.set(*clipRect);
171    inverse.mapRect(mLocalClip);
172
173    return mLocalClip;
174}
175
176void Snapshot::resetClip(float left, float top, float right, float bottom) {
177    // TODO: This is incorrect, when we start rendering into a new layer,
178    // we may have to modify the previous snapshot's clip rect and clip
179    // region if the previous restore() call did not restore the clip
180    clipRect = &mClipRectRoot;
181    clipRegion = &mClipRegionRoot;
182    setClip(left, top, right, bottom);
183}
184
185///////////////////////////////////////////////////////////////////////////////
186// Transforms
187///////////////////////////////////////////////////////////////////////////////
188
189void Snapshot::resetTransform(float x, float y, float z) {
190    transform = &mTransformRoot;
191    transform->loadTranslate(x, y, z);
192}
193
194///////////////////////////////////////////////////////////////////////////////
195// Queries
196///////////////////////////////////////////////////////////////////////////////
197
198bool Snapshot::isIgnored() const {
199    return invisible || empty;
200}
201
202}; // namespace uirenderer
203}; // namespace android
204