1/*
2 * Copyright (C) 2014 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#define LOG_TAG "OpenGLRenderer"
18
19#include <SkCanvas.h>
20
21#include "StatefulBaseRenderer.h"
22
23#include "utils/MathUtils.h"
24
25namespace android {
26namespace uirenderer {
27
28StatefulBaseRenderer::StatefulBaseRenderer()
29        : mDirtyClip(false)
30        , mWidth(-1)
31        , mHeight(-1)
32        , mSaveCount(1)
33        , mFirstSnapshot(new Snapshot)
34        , mSnapshot(mFirstSnapshot) {
35}
36
37void StatefulBaseRenderer::initializeSaveStack(float clipLeft, float clipTop,
38        float clipRight, float clipBottom, const Vector3& lightCenter) {
39    mSnapshot = new Snapshot(mFirstSnapshot,
40            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
41    mSnapshot->setClip(clipLeft, clipTop, clipRight, clipBottom);
42    mSnapshot->fbo = getTargetFbo();
43    mSnapshot->setRelativeLightCenter(lightCenter);
44    mSaveCount = 1;
45}
46
47void StatefulBaseRenderer::setViewport(int width, int height) {
48    mWidth = width;
49    mHeight = height;
50    mFirstSnapshot->initializeViewport(width, height);
51    onViewportInitialized();
52
53    // create a temporary 1st snapshot, so old snapshots are released,
54    // and viewport can be queried safely.
55    // TODO: remove, combine viewport + save stack initialization
56    mSnapshot = new Snapshot(mFirstSnapshot,
57            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
58    mSaveCount = 1;
59}
60
61///////////////////////////////////////////////////////////////////////////////
62// Save (layer)
63///////////////////////////////////////////////////////////////////////////////
64
65/**
66 * Non-virtual implementation of save, guaranteed to save without side-effects
67 *
68 * The approach here and in restoreSnapshot(), allows subclasses to directly manipulate the save
69 * stack, and ensures restoreToCount() doesn't call back into subclass overrides.
70 */
71int StatefulBaseRenderer::saveSnapshot(int flags) {
72    mSnapshot = new Snapshot(mSnapshot, flags);
73    return mSaveCount++;
74}
75
76int StatefulBaseRenderer::save(int flags) {
77    return saveSnapshot(flags);
78}
79
80/**
81 * Non-virtual implementation of restore, guaranteed to restore without side-effects.
82 */
83void StatefulBaseRenderer::restoreSnapshot() {
84    sp<Snapshot> toRemove = mSnapshot;
85    sp<Snapshot> toRestore = mSnapshot->previous;
86
87    mSaveCount--;
88    mSnapshot = toRestore;
89
90    // subclass handles restore implementation
91    onSnapshotRestored(*toRemove, *toRestore);
92}
93
94void StatefulBaseRenderer::restore() {
95    if (mSaveCount > 1) {
96        restoreSnapshot();
97    }
98}
99
100void StatefulBaseRenderer::restoreToCount(int saveCount) {
101    if (saveCount < 1) saveCount = 1;
102
103    while (mSaveCount > saveCount) {
104        restoreSnapshot();
105    }
106}
107
108///////////////////////////////////////////////////////////////////////////////
109// Matrix
110///////////////////////////////////////////////////////////////////////////////
111
112void StatefulBaseRenderer::getMatrix(SkMatrix* matrix) const {
113    mSnapshot->transform->copyTo(*matrix);
114}
115
116void StatefulBaseRenderer::translate(float dx, float dy, float dz) {
117    mSnapshot->transform->translate(dx, dy, dz);
118}
119
120void StatefulBaseRenderer::rotate(float degrees) {
121    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
122}
123
124void StatefulBaseRenderer::scale(float sx, float sy) {
125    mSnapshot->transform->scale(sx, sy, 1.0f);
126}
127
128void StatefulBaseRenderer::skew(float sx, float sy) {
129    mSnapshot->transform->skew(sx, sy);
130}
131
132void StatefulBaseRenderer::setMatrix(const SkMatrix& matrix) {
133    mSnapshot->transform->load(matrix);
134}
135
136void StatefulBaseRenderer::setMatrix(const Matrix4& matrix) {
137    mSnapshot->transform->load(matrix);
138}
139
140void StatefulBaseRenderer::concatMatrix(const SkMatrix& matrix) {
141    mat4 transform(matrix);
142    mSnapshot->transform->multiply(transform);
143}
144
145void StatefulBaseRenderer::concatMatrix(const Matrix4& matrix) {
146    mSnapshot->transform->multiply(matrix);
147}
148
149///////////////////////////////////////////////////////////////////////////////
150// Clip
151///////////////////////////////////////////////////////////////////////////////
152
153bool StatefulBaseRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
154    if (CC_LIKELY(currentTransform()->rectToRect())) {
155        mDirtyClip |= mSnapshot->clip(left, top, right, bottom, op);
156        return !mSnapshot->clipRect->isEmpty();
157    }
158
159    SkPath path;
160    path.addRect(left, top, right, bottom);
161
162    return StatefulBaseRenderer::clipPath(&path, op);
163}
164
165bool StatefulBaseRenderer::clipPath(const SkPath* path, SkRegion::Op op) {
166    SkMatrix transform;
167    currentTransform()->copyTo(transform);
168
169    SkPath transformed;
170    path->transform(transform, &transformed);
171
172    SkRegion clip;
173    if (!mSnapshot->previous->clipRegion->isEmpty()) {
174        clip.setRegion(*mSnapshot->previous->clipRegion);
175    } else {
176        if (mSnapshot->previous == firstSnapshot()) {
177            clip.setRect(0, 0, getWidth(), getHeight());
178        } else {
179            Rect* bounds = mSnapshot->previous->clipRect;
180            clip.setRect(bounds->left, bounds->top, bounds->right, bounds->bottom);
181        }
182    }
183
184    SkRegion region;
185    region.setPath(transformed, clip);
186
187    // region is the transformed input path, masked by the previous clip
188    mDirtyClip |= mSnapshot->clipRegionTransformed(region, op);
189    return !mSnapshot->clipRect->isEmpty();
190}
191
192bool StatefulBaseRenderer::clipRegion(const SkRegion* region, SkRegion::Op op) {
193    mDirtyClip |= mSnapshot->clipRegionTransformed(*region, op);
194    return !mSnapshot->clipRect->isEmpty();
195}
196
197void StatefulBaseRenderer::setClippingOutline(LinearAllocator& allocator, const Outline* outline) {
198    Rect bounds;
199    float radius;
200    if (!outline->getAsRoundRect(&bounds, &radius)) return; // only RR supported
201
202    bool outlineIsRounded = MathUtils::isPositive(radius);
203    if (!outlineIsRounded || currentTransform()->isSimple()) {
204        // TODO: consider storing this rect separately, so that this can't be replaced with clip ops
205        clipRect(bounds.left, bounds.top, bounds.right, bounds.bottom, SkRegion::kIntersect_Op);
206    }
207    if (outlineIsRounded) {
208        setClippingRoundRect(allocator, bounds, radius, false);
209    }
210}
211
212void StatefulBaseRenderer::setClippingRoundRect(LinearAllocator& allocator,
213        const Rect& rect, float radius, bool highPriority) {
214    mSnapshot->setClippingRoundRect(allocator, rect, radius, highPriority);
215}
216
217
218///////////////////////////////////////////////////////////////////////////////
219// Quick Rejection
220///////////////////////////////////////////////////////////////////////////////
221
222/**
223 * Calculates whether content drawn within the passed bounds would be outside of, or intersect with
224 * the clipRect. Does not modify the scissor.
225 *
226 * @param clipRequired if not null, will be set to true if element intersects clip
227 *         (and wasn't rejected)
228 *
229 * @param snapOut if set, the geometry will be treated as having an AA ramp.
230 *         See Rect::snapGeometryToPixelBoundaries()
231 */
232bool StatefulBaseRenderer::calculateQuickRejectForScissor(float left, float top,
233        float right, float bottom,
234        bool* clipRequired, bool* roundRectClipRequired,
235        bool snapOut) const {
236    if (mSnapshot->isIgnored() || bottom <= top || right <= left) {
237        return true;
238    }
239
240    Rect r(left, top, right, bottom);
241    currentTransform()->mapRect(r);
242    r.snapGeometryToPixelBoundaries(snapOut);
243
244    Rect clipRect(*currentClipRect());
245    clipRect.snapToPixelBoundaries();
246
247    if (!clipRect.intersects(r)) return true;
248
249    // clip is required if geometry intersects clip rect
250    if (clipRequired) {
251        *clipRequired = !clipRect.contains(r);
252    }
253
254    // round rect clip is required if RR clip exists, and geometry intersects its corners
255    if (roundRectClipRequired) {
256        *roundRectClipRequired = mSnapshot->roundRectClipState != NULL
257                && mSnapshot->roundRectClipState->areaRequiresRoundRectClip(r);
258    }
259    return false;
260}
261
262/**
263 * Returns false if drawing won't be clipped out.
264 *
265 * Makes the decision conservatively, by rounding out the mapped rect before comparing with the
266 * clipRect. To be used when perfect, pixel accuracy is not possible (esp. with tessellation) but
267 * rejection is still desired.
268 *
269 * This function, unlike quickRejectSetupScissor, should be used where precise geometry information
270 * isn't known (esp. when geometry adjusts based on scale). Generally, this will be first pass
271 * rejection where precise rejection isn't important, or precise information isn't available.
272 */
273bool StatefulBaseRenderer::quickRejectConservative(float left, float top,
274        float right, float bottom) const {
275    if (mSnapshot->isIgnored() || bottom <= top || right <= left) {
276        return true;
277    }
278
279    Rect r(left, top, right, bottom);
280    currentTransform()->mapRect(r);
281    r.roundOut(); // rounded out to be conservative
282
283    Rect clipRect(*currentClipRect());
284    clipRect.snapToPixelBoundaries();
285
286    if (!clipRect.intersects(r)) return true;
287
288    return false;
289}
290
291}; // namespace uirenderer
292}; // namespace android
293