OpenGLRenderer.cpp revision 527a3aace1dd72432c2e0472a570e030ad04bf16 
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#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkPathMeasure.h>
25#include <SkTypeface.h>
26
27#include <utils/Log.h>
28#include <utils/StopWatch.h>
29
30#include <private/hwui/DrawGlInfo.h>
31
32#include <ui/Rect.h>
33
34#include "OpenGLRenderer.h"
35#include "DeferredDisplayList.h"
36#include "DisplayListRenderer.h"
37#include "PathTessellator.h"
38#include "Properties.h"
39#include "Vector.h"
40
41namespace android {
42namespace uirenderer {
43
44///////////////////////////////////////////////////////////////////////////////
45// Defines
46///////////////////////////////////////////////////////////////////////////////
47
48#define RAD_TO_DEG (180.0f / 3.14159265f)
49#define MIN_ANGLE 0.001f
50
51#define ALPHA_THRESHOLD 0
52
53#define FILTER(paint) (!paint || paint->isFilterBitmap() ? GL_LINEAR : GL_NEAREST)
54
55///////////////////////////////////////////////////////////////////////////////
56// Globals
57///////////////////////////////////////////////////////////////////////////////
58
59/**
60 * Structure mapping Skia xfermodes to OpenGL blending factors.
61 */
62struct Blender {
63    SkXfermode::Mode mode;
64    GLenum src;
65    GLenum dst;
66}; // struct Blender
67
68// In this array, the index of each Blender equals the value of the first
69// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
70static const Blender gBlends[] = {
71    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
72    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
73    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
74    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
75    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
76    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
77    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
78    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
79    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
80    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
81    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
82    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
83    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
84    { SkXfermode::kModulate_Mode, GL_ZERO,                GL_SRC_COLOR },
85    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
86};
87
88// This array contains the swapped version of each SkXfermode. For instance
89// this array's SrcOver blending mode is actually DstOver. You can refer to
90// createLayer() for more information on the purpose of this array.
91static const Blender gBlendsSwap[] = {
92    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
93    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
94    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
95    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
96    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
97    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
98    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
99    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
100    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
101    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
102    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
103    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
104    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
105    { SkXfermode::kModulate_Mode, GL_DST_COLOR,           GL_ZERO },
106    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
107};
108
109///////////////////////////////////////////////////////////////////////////////
110// Constructors/destructor
111///////////////////////////////////////////////////////////////////////////////
112
113OpenGLRenderer::OpenGLRenderer():
114        mCaches(Caches::getInstance()), mExtensions(Extensions::getInstance()) {
115    // *set* draw modifiers to be 0
116    memset(&mDrawModifiers, 0, sizeof(mDrawModifiers));
117    mDrawModifiers.mOverrideLayerAlpha = 1.0f;
118
119    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
120
121    mFirstSnapshot = new Snapshot;
122    mFrameStarted = false;
123
124    mScissorOptimizationDisabled = false;
125}
126
127OpenGLRenderer::~OpenGLRenderer() {
128    // The context has already been destroyed at this point, do not call
129    // GL APIs. All GL state should be kept in Caches.h
130}
131
132void OpenGLRenderer::initProperties() {
133    char property[PROPERTY_VALUE_MAX];
134    if (property_get(PROPERTY_DISABLE_SCISSOR_OPTIMIZATION, property, "false")) {
135        mScissorOptimizationDisabled = !strcasecmp(property, "true");
136        INIT_LOGD("  Scissor optimization %s",
137                mScissorOptimizationDisabled ? "disabled" : "enabled");
138    } else {
139        INIT_LOGD("  Scissor optimization enabled");
140    }
141}
142
143///////////////////////////////////////////////////////////////////////////////
144// Setup
145///////////////////////////////////////////////////////////////////////////////
146
147void OpenGLRenderer::setName(const char* name) {
148    if (name) {
149        mName.setTo(name);
150    } else {
151        mName.clear();
152    }
153}
154
155const char* OpenGLRenderer::getName() const {
156    return mName.string();
157}
158
159bool OpenGLRenderer::isDeferred() {
160    return false;
161}
162
163void OpenGLRenderer::setViewport(int width, int height) {
164    initViewport(width, height);
165
166    glDisable(GL_DITHER);
167    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
168
169    glEnableVertexAttribArray(Program::kBindingPosition);
170}
171
172void OpenGLRenderer::initViewport(int width, int height) {
173    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
174
175    mWidth = width;
176    mHeight = height;
177
178    mFirstSnapshot->height = height;
179    mFirstSnapshot->viewport.set(0, 0, width, height);
180}
181
182void OpenGLRenderer::setupFrameState(float left, float top,
183        float right, float bottom, bool opaque) {
184    mCaches.clearGarbage();
185
186    mOpaque = opaque;
187    mSnapshot = new Snapshot(mFirstSnapshot,
188            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
189    mSnapshot->fbo = getTargetFbo();
190    mSaveCount = 1;
191
192    mSnapshot->setClip(left, top, right, bottom);
193    mTilingClip.set(left, top, right, bottom);
194}
195
196status_t OpenGLRenderer::startFrame() {
197    if (mFrameStarted) return DrawGlInfo::kStatusDone;
198    mFrameStarted = true;
199
200    mDirtyClip = true;
201
202    discardFramebuffer(mTilingClip.left, mTilingClip.top, mTilingClip.right, mTilingClip.bottom);
203
204    glViewport(0, 0, mWidth, mHeight);
205
206    // Functors break the tiling extension in pretty spectacular ways
207    // This ensures we don't use tiling when a functor is going to be
208    // invoked during the frame
209    mSuppressTiling = mCaches.hasRegisteredFunctors();
210
211    startTiling(mSnapshot, true);
212
213    debugOverdraw(true, true);
214
215    return clear(mTilingClip.left, mTilingClip.top,
216            mTilingClip.right, mTilingClip.bottom, mOpaque);
217}
218
219status_t OpenGLRenderer::prepare(bool opaque) {
220    return prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
221}
222
223status_t OpenGLRenderer::prepareDirty(float left, float top,
224        float right, float bottom, bool opaque) {
225    setupFrameState(left, top, right, bottom, opaque);
226
227    // Layer renderers will start the frame immediately
228    // The framebuffer renderer will first defer the display list
229    // for each layer and wait until the first drawing command
230    // to start the frame
231    if (mSnapshot->fbo == 0) {
232        syncState();
233        updateLayers();
234    } else {
235        return startFrame();
236    }
237
238    return DrawGlInfo::kStatusDone;
239}
240
241void OpenGLRenderer::discardFramebuffer(float left, float top, float right, float bottom) {
242    // If we know that we are going to redraw the entire framebuffer,
243    // perform a discard to let the driver know we don't need to preserve
244    // the back buffer for this frame.
245    if (mExtensions.hasDiscardFramebuffer() &&
246            left <= 0.0f && top <= 0.0f && right >= mWidth && bottom >= mHeight) {
247        const bool isFbo = getTargetFbo() == 0;
248        const GLenum attachments[] = {
249                isFbo ? (const GLenum) GL_COLOR_EXT : (const GLenum) GL_COLOR_ATTACHMENT0,
250                isFbo ? (const GLenum) GL_STENCIL_EXT : (const GLenum) GL_STENCIL_ATTACHMENT };
251        glDiscardFramebufferEXT(GL_FRAMEBUFFER, 1, attachments);
252    }
253}
254
255status_t OpenGLRenderer::clear(float left, float top, float right, float bottom, bool opaque) {
256    if (!opaque) {
257        mCaches.enableScissor();
258        mCaches.setScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
259        glClear(GL_COLOR_BUFFER_BIT);
260        return DrawGlInfo::kStatusDrew;
261    }
262
263    mCaches.resetScissor();
264    return DrawGlInfo::kStatusDone;
265}
266
267void OpenGLRenderer::syncState() {
268    if (mCaches.blend) {
269        glEnable(GL_BLEND);
270    } else {
271        glDisable(GL_BLEND);
272    }
273}
274
275void OpenGLRenderer::startTiling(const sp<Snapshot>& s, bool opaque) {
276    if (!mSuppressTiling) {
277        Rect* clip = &mTilingClip;
278        if (s->flags & Snapshot::kFlagFboTarget) {
279            clip = &(s->layer->clipRect);
280        }
281
282        startTiling(*clip, s->height, opaque);
283    }
284}
285
286void OpenGLRenderer::startTiling(const Rect& clip, int windowHeight, bool opaque) {
287    if (!mSuppressTiling) {
288        mCaches.startTiling(clip.left, windowHeight - clip.bottom,
289                clip.right - clip.left, clip.bottom - clip.top, opaque);
290    }
291}
292
293void OpenGLRenderer::endTiling() {
294    if (!mSuppressTiling) mCaches.endTiling();
295}
296
297void OpenGLRenderer::finish() {
298    renderOverdraw();
299    endTiling();
300
301    // When finish() is invoked on FBO 0 we've reached the end
302    // of the current frame
303    if (getTargetFbo() == 0) {
304        mCaches.pathCache.trim();
305    }
306
307    if (!suppressErrorChecks()) {
308#if DEBUG_OPENGL
309        GLenum status = GL_NO_ERROR;
310        while ((status = glGetError()) != GL_NO_ERROR) {
311            ALOGD("GL error from OpenGLRenderer: 0x%x", status);
312            switch (status) {
313                case GL_INVALID_ENUM:
314                    ALOGE("  GL_INVALID_ENUM");
315                    break;
316                case GL_INVALID_VALUE:
317                    ALOGE("  GL_INVALID_VALUE");
318                    break;
319                case GL_INVALID_OPERATION:
320                    ALOGE("  GL_INVALID_OPERATION");
321                    break;
322                case GL_OUT_OF_MEMORY:
323                    ALOGE("  Out of memory!");
324                    break;
325            }
326        }
327#endif
328
329#if DEBUG_MEMORY_USAGE
330        mCaches.dumpMemoryUsage();
331#else
332        if (mCaches.getDebugLevel() & kDebugMemory) {
333            mCaches.dumpMemoryUsage();
334        }
335#endif
336    }
337
338    mFrameStarted = false;
339}
340
341void OpenGLRenderer::interrupt() {
342    if (mCaches.currentProgram) {
343        if (mCaches.currentProgram->isInUse()) {
344            mCaches.currentProgram->remove();
345            mCaches.currentProgram = NULL;
346        }
347    }
348    mCaches.unbindMeshBuffer();
349    mCaches.unbindIndicesBuffer();
350    mCaches.resetVertexPointers();
351    mCaches.disableTexCoordsVertexArray();
352    debugOverdraw(false, false);
353}
354
355void OpenGLRenderer::resume() {
356    sp<Snapshot> snapshot = (mSnapshot != NULL) ? mSnapshot : mFirstSnapshot;
357    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
358    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
359    debugOverdraw(true, false);
360
361    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
362
363    mCaches.scissorEnabled = glIsEnabled(GL_SCISSOR_TEST);
364    mCaches.enableScissor();
365    mCaches.resetScissor();
366    dirtyClip();
367
368    mCaches.activeTexture(0);
369
370    mCaches.blend = true;
371    glEnable(GL_BLEND);
372    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
373    glBlendEquation(GL_FUNC_ADD);
374}
375
376void OpenGLRenderer::resumeAfterLayer() {
377    sp<Snapshot> snapshot = (mSnapshot != NULL) ? mSnapshot : mFirstSnapshot;
378    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
379    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
380    debugOverdraw(true, false);
381
382    mCaches.resetScissor();
383    dirtyClip();
384}
385
386void OpenGLRenderer::detachFunctor(Functor* functor) {
387    mFunctors.remove(functor);
388}
389
390void OpenGLRenderer::attachFunctor(Functor* functor) {
391    mFunctors.add(functor);
392}
393
394status_t OpenGLRenderer::invokeFunctors(Rect& dirty) {
395    status_t result = DrawGlInfo::kStatusDone;
396    size_t count = mFunctors.size();
397
398    if (count > 0) {
399        interrupt();
400        SortedVector<Functor*> functors(mFunctors);
401        mFunctors.clear();
402
403        DrawGlInfo info;
404        info.clipLeft = 0;
405        info.clipTop = 0;
406        info.clipRight = 0;
407        info.clipBottom = 0;
408        info.isLayer = false;
409        info.width = 0;
410        info.height = 0;
411        memset(info.transform, 0, sizeof(float) * 16);
412
413        for (size_t i = 0; i < count; i++) {
414            Functor* f = functors.itemAt(i);
415            result |= (*f)(DrawGlInfo::kModeProcess, &info);
416
417            if (result & DrawGlInfo::kStatusDraw) {
418                Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
419                dirty.unionWith(localDirty);
420            }
421
422            if (result & DrawGlInfo::kStatusInvoke) {
423                mFunctors.add(f);
424            }
425        }
426        resume();
427    }
428
429    return result;
430}
431
432status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
433    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
434
435    interrupt();
436    detachFunctor(functor);
437
438    mCaches.enableScissor();
439    if (mDirtyClip) {
440        setScissorFromClip();
441    }
442
443    Rect clip(*mSnapshot->clipRect);
444    clip.snapToPixelBoundaries();
445
446    // Since we don't know what the functor will draw, let's dirty
447    // tne entire clip region
448    if (hasLayer()) {
449        dirtyLayerUnchecked(clip, getRegion());
450    }
451
452    DrawGlInfo info;
453    info.clipLeft = clip.left;
454    info.clipTop = clip.top;
455    info.clipRight = clip.right;
456    info.clipBottom = clip.bottom;
457    info.isLayer = hasLayer();
458    info.width = getSnapshot()->viewport.getWidth();
459    info.height = getSnapshot()->height;
460    getSnapshot()->transform->copyTo(&info.transform[0]);
461
462    status_t result = (*functor)(DrawGlInfo::kModeDraw, &info) | DrawGlInfo::kStatusDrew;
463
464    if (result != DrawGlInfo::kStatusDone) {
465        Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
466        dirty.unionWith(localDirty);
467
468        if (result & DrawGlInfo::kStatusInvoke) {
469            mFunctors.add(functor);
470        }
471    }
472
473    resume();
474    return result;
475}
476
477///////////////////////////////////////////////////////////////////////////////
478// Debug
479///////////////////////////////////////////////////////////////////////////////
480
481void OpenGLRenderer::eventMark(const char* name) const {
482    mCaches.eventMark(0, name);
483}
484
485void OpenGLRenderer::startMark(const char* name) const {
486    mCaches.startMark(0, name);
487}
488
489void OpenGLRenderer::endMark() const {
490    mCaches.endMark();
491}
492
493void OpenGLRenderer::debugOverdraw(bool enable, bool clear) {
494    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
495        if (clear) {
496            mCaches.disableScissor();
497            mCaches.stencil.clear();
498        }
499        if (enable) {
500            mCaches.stencil.enableDebugWrite();
501        } else {
502            mCaches.stencil.disable();
503        }
504    }
505}
506
507void OpenGLRenderer::renderOverdraw() {
508    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
509        const Rect* clip = &mTilingClip;
510
511        mCaches.enableScissor();
512        mCaches.setScissor(clip->left, mFirstSnapshot->height - clip->bottom,
513                clip->right - clip->left, clip->bottom - clip->top);
514
515        mCaches.stencil.enableDebugTest(2);
516        drawColor(0x2f0000ff, SkXfermode::kSrcOver_Mode);
517        mCaches.stencil.enableDebugTest(3);
518        drawColor(0x2f00ff00, SkXfermode::kSrcOver_Mode);
519        mCaches.stencil.enableDebugTest(4);
520        drawColor(0x3fff0000, SkXfermode::kSrcOver_Mode);
521        mCaches.stencil.enableDebugTest(4, true);
522        drawColor(0x7fff0000, SkXfermode::kSrcOver_Mode);
523        mCaches.stencil.disable();
524    }
525}
526
527///////////////////////////////////////////////////////////////////////////////
528// Layers
529///////////////////////////////////////////////////////////////////////////////
530
531bool OpenGLRenderer::updateLayer(Layer* layer, bool inFrame) {
532    if (layer->deferredUpdateScheduled && layer->renderer &&
533            layer->displayList && layer->displayList->isRenderable()) {
534        Rect& dirty = layer->dirtyRect;
535
536        if (inFrame) {
537            endTiling();
538            debugOverdraw(false, false);
539        }
540
541        if (CC_UNLIKELY(inFrame || mCaches.drawDeferDisabled)) {
542            layer->render();
543        } else {
544            layer->defer();
545        }
546
547        if (inFrame) {
548            resumeAfterLayer();
549            startTiling(mSnapshot);
550        }
551
552        layer->debugDrawUpdate = mCaches.debugLayersUpdates;
553
554        return true;
555    }
556
557    return false;
558}
559
560void OpenGLRenderer::updateLayers() {
561    // If draw deferring is enabled this method will simply defer
562    // the display list of each individual layer. The layers remain
563    // in the layer updates list which will be cleared by flushLayers().
564    int count = mLayerUpdates.size();
565    if (count > 0) {
566        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
567            startMark("Layer Updates");
568        } else {
569            startMark("Defer Layer Updates");
570        }
571
572        // Note: it is very important to update the layers in order
573        for (int i = 0; i < count; i++) {
574            Layer* layer = mLayerUpdates.itemAt(i);
575            updateLayer(layer, false);
576            if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
577                mCaches.resourceCache.decrementRefcount(layer);
578            }
579        }
580
581        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
582            mLayerUpdates.clear();
583            glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
584        }
585        endMark();
586    }
587}
588
589void OpenGLRenderer::flushLayers() {
590    int count = mLayerUpdates.size();
591    if (count > 0) {
592        startMark("Apply Layer Updates");
593        char layerName[12];
594
595        // Note: it is very important to update the layers in order
596        for (int i = 0; i < count; i++) {
597            sprintf(layerName, "Layer #%d", i);
598            startMark(layerName);
599
600            Layer* layer = mLayerUpdates.itemAt(i);
601            layer->flush();
602            mCaches.resourceCache.decrementRefcount(layer);
603
604            endMark();
605        }
606
607        mLayerUpdates.clear();
608        glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
609
610        endMark();
611    }
612}
613
614void OpenGLRenderer::pushLayerUpdate(Layer* layer) {
615    if (layer) {
616        // Make sure we don't introduce duplicates.
617        // SortedVector would do this automatically but we need to respect
618        // the insertion order. The linear search is not an issue since
619        // this list is usually very short (typically one item, at most a few)
620        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
621            if (mLayerUpdates.itemAt(i) == layer) {
622                return;
623            }
624        }
625        mLayerUpdates.push_back(layer);
626        mCaches.resourceCache.incrementRefcount(layer);
627    }
628}
629
630void OpenGLRenderer::clearLayerUpdates() {
631    size_t count = mLayerUpdates.size();
632    if (count > 0) {
633        mCaches.resourceCache.lock();
634        for (size_t i = 0; i < count; i++) {
635            mCaches.resourceCache.decrementRefcountLocked(mLayerUpdates.itemAt(i));
636        }
637        mCaches.resourceCache.unlock();
638        mLayerUpdates.clear();
639    }
640}
641
642///////////////////////////////////////////////////////////////////////////////
643// State management
644///////////////////////////////////////////////////////////////////////////////
645
646int OpenGLRenderer::getSaveCount() const {
647    return mSaveCount;
648}
649
650int OpenGLRenderer::save(int flags) {
651    return saveSnapshot(flags);
652}
653
654void OpenGLRenderer::restore() {
655    if (mSaveCount > 1) {
656        restoreSnapshot();
657    }
658}
659
660void OpenGLRenderer::restoreToCount(int saveCount) {
661    if (saveCount < 1) saveCount = 1;
662
663    while (mSaveCount > saveCount) {
664        restoreSnapshot();
665    }
666}
667
668int OpenGLRenderer::saveSnapshot(int flags) {
669    mSnapshot = new Snapshot(mSnapshot, flags);
670    return mSaveCount++;
671}
672
673bool OpenGLRenderer::restoreSnapshot() {
674    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
675    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
676    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
677
678    sp<Snapshot> current = mSnapshot;
679    sp<Snapshot> previous = mSnapshot->previous;
680
681    if (restoreOrtho) {
682        Rect& r = previous->viewport;
683        glViewport(r.left, r.top, r.right, r.bottom);
684        mOrthoMatrix.load(current->orthoMatrix);
685    }
686
687    mSaveCount--;
688    mSnapshot = previous;
689
690    if (restoreClip) {
691        dirtyClip();
692    }
693
694    if (restoreLayer) {
695        endMark(); // Savelayer
696        startMark("ComposeLayer");
697        composeLayer(current, previous);
698        endMark();
699    }
700
701    return restoreClip;
702}
703
704///////////////////////////////////////////////////////////////////////////////
705// Layers
706///////////////////////////////////////////////////////////////////////////////
707
708int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
709        int alpha, SkXfermode::Mode mode, int flags) {
710    const GLuint previousFbo = mSnapshot->fbo;
711    const int count = saveSnapshot(flags);
712
713    if (!mSnapshot->isIgnored()) {
714        createLayer(left, top, right, bottom, alpha, mode, flags, previousFbo);
715    }
716
717    return count;
718}
719
720void OpenGLRenderer::calculateLayerBoundsAndClip(Rect& bounds, Rect& clip, bool fboLayer) {
721    const Rect untransformedBounds(bounds);
722
723    currentTransform().mapRect(bounds);
724
725    // Layers only make sense if they are in the framebuffer's bounds
726    if (bounds.intersect(*mSnapshot->clipRect)) {
727        // We cannot work with sub-pixels in this case
728        bounds.snapToPixelBoundaries();
729
730        // When the layer is not an FBO, we may use glCopyTexImage so we
731        // need to make sure the layer does not extend outside the bounds
732        // of the framebuffer
733        if (!bounds.intersect(mSnapshot->previous->viewport)) {
734            bounds.setEmpty();
735        } else if (fboLayer) {
736            clip.set(bounds);
737            mat4 inverse;
738            inverse.loadInverse(currentTransform());
739            inverse.mapRect(clip);
740            clip.snapToPixelBoundaries();
741            if (clip.intersect(untransformedBounds)) {
742                clip.translate(-untransformedBounds.left, -untransformedBounds.top);
743                bounds.set(untransformedBounds);
744            } else {
745                clip.setEmpty();
746            }
747        }
748    } else {
749        bounds.setEmpty();
750    }
751}
752
753void OpenGLRenderer::updateSnapshotIgnoreForLayer(const Rect& bounds, const Rect& clip,
754        bool fboLayer, int alpha) {
755    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
756            bounds.getHeight() > mCaches.maxTextureSize ||
757            (fboLayer && clip.isEmpty())) {
758        mSnapshot->empty = fboLayer;
759    } else {
760        mSnapshot->invisible = mSnapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
761    }
762}
763
764int OpenGLRenderer::saveLayerDeferred(float left, float top, float right, float bottom,
765        int alpha, SkXfermode::Mode mode, int flags) {
766    const GLuint previousFbo = mSnapshot->fbo;
767    const int count = saveSnapshot(flags);
768
769    if (!mSnapshot->isIgnored() && (flags & SkCanvas::kClipToLayer_SaveFlag)) {
770        // initialize the snapshot as though it almost represents an FBO layer so deferred draw
771        // operations will be able to store and restore the current clip and transform info, and
772        // quick rejection will be correct (for display lists)
773
774        Rect bounds(left, top, right, bottom);
775        Rect clip;
776        calculateLayerBoundsAndClip(bounds, clip, true);
777        updateSnapshotIgnoreForLayer(bounds, clip, true, alpha);
778
779        if (!mSnapshot->isIgnored()) {
780            mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
781            mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
782        }
783    }
784
785    return count;
786}
787
788
789/**
790 * Layers are viewed by Skia are slightly different than layers in image editing
791 * programs (for instance.) When a layer is created, previously created layers
792 * and the frame buffer still receive every drawing command. For instance, if a
793 * layer is created and a shape intersecting the bounds of the layers and the
794 * framebuffer is draw, the shape will be drawn on both (unless the layer was
795 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
796 *
797 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
798 * texture. Unfortunately, this is inefficient as it requires every primitive to
799 * be drawn n + 1 times, where n is the number of active layers. In practice this
800 * means, for every primitive:
801 *   - Switch active frame buffer
802 *   - Change viewport, clip and projection matrix
803 *   - Issue the drawing
804 *
805 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
806 * To avoid this, layers are implemented in a different way here, at least in the
807 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
808 * is set. When this flag is set we can redirect all drawing operations into a
809 * single FBO.
810 *
811 * This implementation relies on the frame buffer being at least RGBA 8888. When
812 * a layer is created, only a texture is created, not an FBO. The content of the
813 * frame buffer contained within the layer's bounds is copied into this texture
814 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
815 * buffer and drawing continues as normal. This technique therefore treats the
816 * frame buffer as a scratch buffer for the layers.
817 *
818 * To compose the layers back onto the frame buffer, each layer texture
819 * (containing the original frame buffer data) is drawn as a simple quad over
820 * the frame buffer. The trick is that the quad is set as the composition
821 * destination in the blending equation, and the frame buffer becomes the source
822 * of the composition.
823 *
824 * Drawing layers with an alpha value requires an extra step before composition.
825 * An empty quad is drawn over the layer's region in the frame buffer. This quad
826 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
827 * quad is used to multiply the colors in the frame buffer. This is achieved by
828 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
829 * GL_ZERO, GL_SRC_ALPHA.
830 *
831 * Because glCopyTexImage2D() can be slow, an alternative implementation might
832 * be use to draw a single clipped layer. The implementation described above
833 * is correct in every case.
834 *
835 * (1) The frame buffer is actually not cleared right away. To allow the GPU
836 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
837 *     buffer is left untouched until the first drawing operation. Only when
838 *     something actually gets drawn are the layers regions cleared.
839 */
840bool OpenGLRenderer::createLayer(float left, float top, float right, float bottom,
841        int alpha, SkXfermode::Mode mode, int flags, GLuint previousFbo) {
842    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
843    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
844
845    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
846
847    // Window coordinates of the layer
848    Rect clip;
849    Rect bounds(left, top, right, bottom);
850    calculateLayerBoundsAndClip(bounds, clip, fboLayer);
851    updateSnapshotIgnoreForLayer(bounds, clip, fboLayer, alpha);
852
853    // Bail out if we won't draw in this snapshot
854    if (mSnapshot->isIgnored()) {
855        return false;
856    }
857
858    mCaches.activeTexture(0);
859    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
860    if (!layer) {
861        return false;
862    }
863
864    layer->setAlpha(alpha, mode);
865    layer->layer.set(bounds);
866    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
867            bounds.getWidth() / float(layer->getWidth()), 0.0f);
868    layer->setColorFilter(mDrawModifiers.mColorFilter);
869    layer->setBlend(true);
870    layer->setDirty(false);
871
872    // Save the layer in the snapshot
873    mSnapshot->flags |= Snapshot::kFlagIsLayer;
874    mSnapshot->layer = layer;
875
876    startMark("SaveLayer");
877    if (fboLayer) {
878        return createFboLayer(layer, bounds, clip, previousFbo);
879    } else {
880        // Copy the framebuffer into the layer
881        layer->bindTexture();
882        if (!bounds.isEmpty()) {
883            if (layer->isEmpty()) {
884                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
885                        bounds.left, mSnapshot->height - bounds.bottom,
886                        layer->getWidth(), layer->getHeight(), 0);
887                layer->setEmpty(false);
888            } else {
889                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
890                        mSnapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
891            }
892
893            // Enqueue the buffer coordinates to clear the corresponding region later
894            mLayers.push(new Rect(bounds));
895        }
896    }
897
898    return true;
899}
900
901bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, Rect& clip, GLuint previousFbo) {
902    layer->clipRect.set(clip);
903    layer->setFbo(mCaches.fboCache.get());
904
905    mSnapshot->region = &mSnapshot->layer->region;
906    mSnapshot->flags |= Snapshot::kFlagFboTarget | Snapshot::kFlagIsFboLayer |
907            Snapshot::kFlagDirtyOrtho;
908    mSnapshot->fbo = layer->getFbo();
909    mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
910    mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
911    mSnapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
912    mSnapshot->height = bounds.getHeight();
913    mSnapshot->orthoMatrix.load(mOrthoMatrix);
914
915    endTiling();
916    debugOverdraw(false, false);
917    // Bind texture to FBO
918    glBindFramebuffer(GL_FRAMEBUFFER, layer->getFbo());
919    layer->bindTexture();
920
921    // Initialize the texture if needed
922    if (layer->isEmpty()) {
923        layer->allocateTexture();
924        layer->setEmpty(false);
925    }
926
927    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
928            layer->getTexture(), 0);
929
930    startTiling(mSnapshot, true);
931
932    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
933    mCaches.enableScissor();
934    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
935            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
936    glClear(GL_COLOR_BUFFER_BIT);
937
938    dirtyClip();
939
940    // Change the ortho projection
941    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
942    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
943
944    return true;
945}
946
947/**
948 * Read the documentation of createLayer() before doing anything in this method.
949 */
950void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
951    if (!current->layer) {
952        ALOGE("Attempting to compose a layer that does not exist");
953        return;
954    }
955
956    Layer* layer = current->layer;
957    const Rect& rect = layer->layer;
958    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
959
960    if (fboLayer) {
961        endTiling();
962
963        // Detach the texture from the FBO
964        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
965
966        layer->removeFbo(false);
967
968        // Unbind current FBO and restore previous one
969        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
970        debugOverdraw(true, false);
971
972        startTiling(previous);
973    }
974
975    if (!fboLayer && layer->getAlpha() < 255) {
976        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
977                layer->getAlpha() << 24, SkXfermode::kDstIn_Mode, true);
978        // Required below, composeLayerRect() will divide by 255
979        layer->setAlpha(255);
980    }
981
982    mCaches.unbindMeshBuffer();
983
984    mCaches.activeTexture(0);
985
986    // When the layer is stored in an FBO, we can save a bit of fillrate by
987    // drawing only the dirty region
988    if (fboLayer) {
989        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
990        if (layer->getColorFilter()) {
991            setupColorFilter(layer->getColorFilter());
992        }
993        composeLayerRegion(layer, rect);
994        if (layer->getColorFilter()) {
995            resetColorFilter();
996        }
997    } else if (!rect.isEmpty()) {
998        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
999        composeLayerRect(layer, rect, true);
1000    }
1001
1002    dirtyClip();
1003
1004    // Failing to add the layer to the cache should happen only if the layer is too large
1005    if (!mCaches.layerCache.put(layer)) {
1006        LAYER_LOGD("Deleting layer");
1007        Caches::getInstance().resourceCache.decrementRefcount(layer);
1008    }
1009}
1010
1011void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
1012    float alpha = layer->getAlpha() / 255.0f * mSnapshot->alpha;
1013
1014    setupDraw();
1015    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
1016        setupDrawWithTexture();
1017    } else {
1018        setupDrawWithExternalTexture();
1019    }
1020    setupDrawTextureTransform();
1021    setupDrawColor(alpha, alpha, alpha, alpha);
1022    setupDrawColorFilter();
1023    setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode());
1024    setupDrawProgram();
1025    setupDrawPureColorUniforms();
1026    setupDrawColorFilterUniforms();
1027    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
1028        setupDrawTexture(layer->getTexture());
1029    } else {
1030        setupDrawExternalTexture(layer->getTexture());
1031    }
1032    if (currentTransform().isPureTranslate() &&
1033            layer->getWidth() == (uint32_t) rect.getWidth() &&
1034            layer->getHeight() == (uint32_t) rect.getHeight()) {
1035        const float x = (int) floorf(rect.left + currentTransform().getTranslateX() + 0.5f);
1036        const float y = (int) floorf(rect.top + currentTransform().getTranslateY() + 0.5f);
1037
1038        layer->setFilter(GL_NEAREST);
1039        setupDrawModelView(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1040    } else {
1041        layer->setFilter(GL_LINEAR);
1042        setupDrawModelView(rect.left, rect.top, rect.right, rect.bottom);
1043    }
1044    setupDrawTextureTransformUniforms(layer->getTexTransform());
1045    setupDrawMesh(&mMeshVertices[0].position[0], &mMeshVertices[0].texture[0]);
1046
1047    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1048
1049    finishDrawTexture();
1050}
1051
1052void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
1053    if (!layer->isTextureLayer()) {
1054        const Rect& texCoords = layer->texCoords;
1055        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
1056                texCoords.right, texCoords.bottom);
1057
1058        float x = rect.left;
1059        float y = rect.top;
1060        bool simpleTransform = currentTransform().isPureTranslate() &&
1061                layer->getWidth() == (uint32_t) rect.getWidth() &&
1062                layer->getHeight() == (uint32_t) rect.getHeight();
1063
1064        if (simpleTransform) {
1065            // When we're swapping, the layer is already in screen coordinates
1066            if (!swap) {
1067                x = (int) floorf(rect.left + currentTransform().getTranslateX() + 0.5f);
1068                y = (int) floorf(rect.top + currentTransform().getTranslateY() + 0.5f);
1069            }
1070
1071            layer->setFilter(GL_NEAREST, true);
1072        } else {
1073            layer->setFilter(GL_LINEAR, true);
1074        }
1075
1076        float alpha = getLayerAlpha(layer);
1077        bool blend = layer->isBlend() || alpha < 1.0f;
1078        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
1079                layer->getTexture(), alpha, layer->getMode(), blend,
1080                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1081                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
1082
1083        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1084    } else {
1085        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
1086        drawTextureLayer(layer, rect);
1087        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1088    }
1089}
1090
1091void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
1092    if (layer->region.isRect()) {
1093        layer->setRegionAsRect();
1094
1095        composeLayerRect(layer, layer->regionRect);
1096
1097        layer->region.clear();
1098        return;
1099    }
1100
1101    // TODO: See LayerRenderer.cpp::generateMesh() for important
1102    //       information about this implementation
1103    if (CC_LIKELY(!layer->region.isEmpty())) {
1104        size_t count;
1105        const android::Rect* rects;
1106        Region safeRegion;
1107        if (CC_LIKELY(hasRectToRectTransform())) {
1108            rects = layer->region.getArray(&count);
1109        } else {
1110            safeRegion = Region::createTJunctionFreeRegion(layer->region);
1111            rects = safeRegion.getArray(&count);
1112        }
1113
1114        const float alpha = getLayerAlpha(layer);
1115        const float texX = 1.0f / float(layer->getWidth());
1116        const float texY = 1.0f / float(layer->getHeight());
1117        const float height = rect.getHeight();
1118
1119        setupDraw();
1120
1121        // We must get (and therefore bind) the region mesh buffer
1122        // after we setup drawing in case we need to mess with the
1123        // stencil buffer in setupDraw()
1124        TextureVertex* mesh = mCaches.getRegionMesh();
1125        GLsizei numQuads = 0;
1126
1127        setupDrawWithTexture();
1128        setupDrawColor(alpha, alpha, alpha, alpha);
1129        setupDrawColorFilter();
1130        setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode(), false);
1131        setupDrawProgram();
1132        setupDrawDirtyRegionsDisabled();
1133        setupDrawPureColorUniforms();
1134        setupDrawColorFilterUniforms();
1135        setupDrawTexture(layer->getTexture());
1136        if (currentTransform().isPureTranslate()) {
1137            const float x = (int) floorf(rect.left + currentTransform().getTranslateX() + 0.5f);
1138            const float y = (int) floorf(rect.top + currentTransform().getTranslateY() + 0.5f);
1139
1140            layer->setFilter(GL_NEAREST);
1141            setupDrawModelViewTranslate(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1142        } else {
1143            layer->setFilter(GL_LINEAR);
1144            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1145        }
1146        setupDrawMeshIndices(&mesh[0].position[0], &mesh[0].texture[0]);
1147
1148        for (size_t i = 0; i < count; i++) {
1149            const android::Rect* r = &rects[i];
1150
1151            const float u1 = r->left * texX;
1152            const float v1 = (height - r->top) * texY;
1153            const float u2 = r->right * texX;
1154            const float v2 = (height - r->bottom) * texY;
1155
1156            // TODO: Reject quads outside of the clip
1157            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
1158            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
1159            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
1160            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
1161
1162            numQuads++;
1163
1164            if (numQuads >= REGION_MESH_QUAD_COUNT) {
1165                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
1166                numQuads = 0;
1167                mesh = mCaches.getRegionMesh();
1168            }
1169        }
1170
1171        if (numQuads > 0) {
1172            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
1173        }
1174
1175        finishDrawTexture();
1176
1177#if DEBUG_LAYERS_AS_REGIONS
1178        drawRegionRects(layer->region);
1179#endif
1180
1181        layer->region.clear();
1182    }
1183}
1184
1185void OpenGLRenderer::drawRegionRects(const Region& region) {
1186#if DEBUG_LAYERS_AS_REGIONS
1187    size_t count;
1188    const android::Rect* rects = region.getArray(&count);
1189
1190    uint32_t colors[] = {
1191            0x7fff0000, 0x7f00ff00,
1192            0x7f0000ff, 0x7fff00ff,
1193    };
1194
1195    int offset = 0;
1196    int32_t top = rects[0].top;
1197
1198    for (size_t i = 0; i < count; i++) {
1199        if (top != rects[i].top) {
1200            offset ^= 0x2;
1201            top = rects[i].top;
1202        }
1203
1204        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
1205        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
1206                SkXfermode::kSrcOver_Mode);
1207    }
1208#endif
1209}
1210
1211void OpenGLRenderer::drawRegionRects(const SkRegion& region, int color,
1212        SkXfermode::Mode mode, bool dirty) {
1213    int count = 0;
1214    Vector<float> rects;
1215
1216    SkRegion::Iterator it(region);
1217    while (!it.done()) {
1218        const SkIRect& r = it.rect();
1219        rects.push(r.fLeft);
1220        rects.push(r.fTop);
1221        rects.push(r.fRight);
1222        rects.push(r.fBottom);
1223        count += 4;
1224        it.next();
1225    }
1226
1227    drawColorRects(rects.array(), count, color, mode, true, dirty, false);
1228}
1229
1230void OpenGLRenderer::dirtyLayer(const float left, const float top,
1231        const float right, const float bottom, const mat4 transform) {
1232    if (hasLayer()) {
1233        Rect bounds(left, top, right, bottom);
1234        transform.mapRect(bounds);
1235        dirtyLayerUnchecked(bounds, getRegion());
1236    }
1237}
1238
1239void OpenGLRenderer::dirtyLayer(const float left, const float top,
1240        const float right, const float bottom) {
1241    if (hasLayer()) {
1242        Rect bounds(left, top, right, bottom);
1243        dirtyLayerUnchecked(bounds, getRegion());
1244    }
1245}
1246
1247void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
1248    if (bounds.intersect(*mSnapshot->clipRect)) {
1249        bounds.snapToPixelBoundaries();
1250        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1251        if (!dirty.isEmpty()) {
1252            region->orSelf(dirty);
1253        }
1254    }
1255}
1256
1257void OpenGLRenderer::clearLayerRegions() {
1258    const size_t count = mLayers.size();
1259    if (count == 0) return;
1260
1261    if (!mSnapshot->isIgnored()) {
1262        // Doing several glScissor/glClear here can negatively impact
1263        // GPUs with a tiler architecture, instead we draw quads with
1264        // the Clear blending mode
1265
1266        // The list contains bounds that have already been clipped
1267        // against their initial clip rect, and the current clip
1268        // is likely different so we need to disable clipping here
1269        bool scissorChanged = mCaches.disableScissor();
1270
1271        Vertex mesh[count * 6];
1272        Vertex* vertex = mesh;
1273
1274        for (uint32_t i = 0; i < count; i++) {
1275            Rect* bounds = mLayers.itemAt(i);
1276
1277            Vertex::set(vertex++, bounds->left, bounds->bottom);
1278            Vertex::set(vertex++, bounds->left, bounds->top);
1279            Vertex::set(vertex++, bounds->right, bounds->top);
1280            Vertex::set(vertex++, bounds->left, bounds->bottom);
1281            Vertex::set(vertex++, bounds->right, bounds->top);
1282            Vertex::set(vertex++, bounds->right, bounds->bottom);
1283
1284            delete bounds;
1285        }
1286        // We must clear the list of dirty rects before we
1287        // call setupDraw() to prevent stencil setup to do
1288        // the same thing again
1289        mLayers.clear();
1290
1291        setupDraw(false);
1292        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
1293        setupDrawBlending(true, SkXfermode::kClear_Mode);
1294        setupDrawProgram();
1295        setupDrawPureColorUniforms();
1296        setupDrawModelViewTranslate(0.0f, 0.0f, 0.0f, 0.0f, true);
1297        setupDrawVertices(&mesh[0].position[0]);
1298
1299        glDrawArrays(GL_TRIANGLES, 0, count * 6);
1300
1301        if (scissorChanged) mCaches.enableScissor();
1302    } else {
1303        for (uint32_t i = 0; i < count; i++) {
1304            delete mLayers.itemAt(i);
1305        }
1306        mLayers.clear();
1307    }
1308}
1309
1310///////////////////////////////////////////////////////////////////////////////
1311// State Deferral
1312///////////////////////////////////////////////////////////////////////////////
1313
1314bool OpenGLRenderer::storeDisplayState(DeferredDisplayState& state, int stateDeferFlags) {
1315    const Rect& currentClip = *(mSnapshot->clipRect);
1316    const mat4& currentMatrix = *(mSnapshot->transform);
1317
1318    if (stateDeferFlags & kStateDeferFlag_Draw) {
1319        // state has bounds initialized in local coordinates
1320        if (!state.mBounds.isEmpty()) {
1321            currentMatrix.mapRect(state.mBounds);
1322            if (!state.mBounds.intersect(currentClip)) {
1323                // quick rejected
1324                return true;
1325            }
1326        } else {
1327            state.mBounds.set(currentClip);
1328        }
1329    }
1330
1331    state.mClipValid = (stateDeferFlags & kStateDeferFlag_Clip);
1332    if (state.mClipValid) {
1333        state.mClip.set(currentClip);
1334    }
1335
1336    // Transform, drawModifiers, and alpha always deferred, since they are used by state operations
1337    // (Note: saveLayer/restore use colorFilter and alpha, so we just save restore everything)
1338    state.mMatrix.load(currentMatrix);
1339    state.mDrawModifiers = mDrawModifiers;
1340    state.mAlpha = mSnapshot->alpha;
1341    return false;
1342}
1343
1344void OpenGLRenderer::restoreDisplayState(const DeferredDisplayState& state, bool skipClipRestore) {
1345    currentTransform().load(state.mMatrix);
1346    mDrawModifiers = state.mDrawModifiers;
1347    mSnapshot->alpha = state.mAlpha;
1348
1349    if (state.mClipValid && !skipClipRestore) {
1350        mSnapshot->setClip(state.mClip.left, state.mClip.top, state.mClip.right, state.mClip.bottom);
1351        dirtyClip();
1352    }
1353}
1354
1355void OpenGLRenderer::setFullScreenClip() {
1356    mSnapshot->setClip(0, 0, mWidth, mHeight);
1357    dirtyClip();
1358}
1359
1360///////////////////////////////////////////////////////////////////////////////
1361// Transforms
1362///////////////////////////////////////////////////////////////////////////////
1363
1364void OpenGLRenderer::translate(float dx, float dy) {
1365    currentTransform().translate(dx, dy, 0.0f);
1366}
1367
1368void OpenGLRenderer::rotate(float degrees) {
1369    currentTransform().rotate(degrees, 0.0f, 0.0f, 1.0f);
1370}
1371
1372void OpenGLRenderer::scale(float sx, float sy) {
1373    currentTransform().scale(sx, sy, 1.0f);
1374}
1375
1376void OpenGLRenderer::skew(float sx, float sy) {
1377    currentTransform().skew(sx, sy);
1378}
1379
1380void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
1381    if (matrix) {
1382        currentTransform().load(*matrix);
1383    } else {
1384        currentTransform().loadIdentity();
1385    }
1386}
1387
1388bool OpenGLRenderer::hasRectToRectTransform() {
1389    return CC_LIKELY(currentTransform().rectToRect());
1390}
1391
1392void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
1393    currentTransform().copyTo(*matrix);
1394}
1395
1396void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
1397    SkMatrix transform;
1398    currentTransform().copyTo(transform);
1399    transform.preConcat(*matrix);
1400    currentTransform().load(transform);
1401}
1402
1403///////////////////////////////////////////////////////////////////////////////
1404// Clipping
1405///////////////////////////////////////////////////////////////////////////////
1406
1407void OpenGLRenderer::setScissorFromClip() {
1408    Rect clip(*mSnapshot->clipRect);
1409    clip.snapToPixelBoundaries();
1410
1411    if (mCaches.setScissor(clip.left, mSnapshot->height - clip.bottom,
1412            clip.getWidth(), clip.getHeight())) {
1413        mDirtyClip = false;
1414    }
1415}
1416
1417void OpenGLRenderer::ensureStencilBuffer() {
1418    // Thanks to the mismatch between EGL and OpenGL ES FBO we
1419    // cannot attach a stencil buffer to fbo0 dynamically. Let's
1420    // just hope we have one when hasLayer() returns false.
1421    if (hasLayer()) {
1422        attachStencilBufferToLayer(mSnapshot->layer);
1423    }
1424}
1425
1426void OpenGLRenderer::attachStencilBufferToLayer(Layer* layer) {
1427    // The layer's FBO is already bound when we reach this stage
1428    if (!layer->getStencilRenderBuffer()) {
1429        // GL_QCOM_tiled_rendering doesn't like it if a renderbuffer
1430        // is attached after we initiated tiling. We must turn it off,
1431        // attach the new render buffer then turn tiling back on
1432        endTiling();
1433
1434        RenderBuffer* buffer = mCaches.renderBufferCache.get(
1435                Stencil::getSmallestStencilFormat(), layer->getWidth(), layer->getHeight());
1436        layer->setStencilRenderBuffer(buffer);
1437
1438        startTiling(layer->clipRect, layer->layer.getHeight());
1439    }
1440}
1441
1442void OpenGLRenderer::setStencilFromClip() {
1443    if (!mCaches.debugOverdraw) {
1444        if (!mSnapshot->clipRegion->isEmpty()) {
1445            // NOTE: The order here is important, we must set dirtyClip to false
1446            //       before any draw call to avoid calling back into this method
1447            mDirtyClip = false;
1448
1449            ensureStencilBuffer();
1450
1451            mCaches.stencil.enableWrite();
1452
1453            // Clear the stencil but first make sure we restrict drawing
1454            // to the region's bounds
1455            bool resetScissor = mCaches.enableScissor();
1456            if (resetScissor) {
1457                // The scissor was not set so we now need to update it
1458                setScissorFromClip();
1459            }
1460            mCaches.stencil.clear();
1461            if (resetScissor) mCaches.disableScissor();
1462
1463            // NOTE: We could use the region contour path to generate a smaller mesh
1464            //       Since we are using the stencil we could use the red book path
1465            //       drawing technique. It might increase bandwidth usage though.
1466
1467            // The last parameter is important: we are not drawing in the color buffer
1468            // so we don't want to dirty the current layer, if any
1469            drawRegionRects(*mSnapshot->clipRegion, 0xff000000, SkXfermode::kSrc_Mode, false);
1470
1471            mCaches.stencil.enableTest();
1472
1473            // Draw the region used to generate the stencil if the appropriate debug
1474            // mode is enabled
1475            if (mCaches.debugStencilClip == Caches::kStencilShowRegion) {
1476                drawRegionRects(*mSnapshot->clipRegion, 0x7f0000ff, SkXfermode::kSrcOver_Mode);
1477            }
1478        } else {
1479            mCaches.stencil.disable();
1480        }
1481    }
1482}
1483
1484const Rect& OpenGLRenderer::getClipBounds() {
1485    return mSnapshot->getLocalClip();
1486}
1487
1488bool OpenGLRenderer::quickRejectNoScissor(float left, float top, float right, float bottom) {
1489    if (mSnapshot->isIgnored()) {
1490        return true;
1491    }
1492
1493    Rect r(left, top, right, bottom);
1494    currentTransform().mapRect(r);
1495    r.snapToPixelBoundaries();
1496
1497    Rect clipRect(*mSnapshot->clipRect);
1498    clipRect.snapToPixelBoundaries();
1499
1500    return !clipRect.intersects(r);
1501}
1502
1503bool OpenGLRenderer::quickRejectNoScissor(float left, float top, float right, float bottom,
1504        Rect& transformed, Rect& clip) {
1505    if (mSnapshot->isIgnored()) {
1506        return true;
1507    }
1508
1509    transformed.set(left, top, right, bottom);
1510    currentTransform().mapRect(transformed);
1511    transformed.snapToPixelBoundaries();
1512
1513    clip.set(*mSnapshot->clipRect);
1514    clip.snapToPixelBoundaries();
1515
1516    return !clip.intersects(transformed);
1517}
1518
1519bool OpenGLRenderer::quickRejectPreStroke(float left, float top, float right, float bottom,
1520        SkPaint* paint) {
1521    if (paint->getStyle() != SkPaint::kFill_Style) {
1522        float outset = paint->getStrokeWidth() * 0.5f;
1523        return quickReject(left - outset, top - outset, right + outset, bottom + outset);
1524    } else {
1525        return quickReject(left, top, right, bottom);
1526    }
1527}
1528
1529bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
1530    if (mSnapshot->isIgnored() || bottom <= top || right <= left) {
1531        return true;
1532    }
1533
1534    Rect r(left, top, right, bottom);
1535    currentTransform().mapRect(r);
1536    r.snapToPixelBoundaries();
1537
1538    Rect clipRect(*mSnapshot->clipRect);
1539    clipRect.snapToPixelBoundaries();
1540
1541    bool rejected = !clipRect.intersects(r);
1542    if (!isDeferred() && !rejected) {
1543        mCaches.setScissorEnabled(mScissorOptimizationDisabled || !clipRect.contains(r));
1544    }
1545
1546    return rejected;
1547}
1548
1549void OpenGLRenderer::debugClip() {
1550#if DEBUG_CLIP_REGIONS
1551    if (!isDeferred() && !mSnapshot->clipRegion->isEmpty()) {
1552        drawRegionRects(*mSnapshot->clipRegion, 0x7f00ff00, SkXfermode::kSrcOver_Mode);
1553    }
1554#endif
1555}
1556
1557bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
1558    if (CC_LIKELY(currentTransform().rectToRect())) {
1559        bool clipped = mSnapshot->clip(left, top, right, bottom, op);
1560        if (clipped) {
1561            dirtyClip();
1562        }
1563        return !mSnapshot->clipRect->isEmpty();
1564    }
1565
1566    SkPath path;
1567    path.addRect(left, top, right, bottom);
1568
1569    return clipPath(&path, op);
1570}
1571
1572bool OpenGLRenderer::clipPath(SkPath* path, SkRegion::Op op) {
1573    SkMatrix transform;
1574    currentTransform().copyTo(transform);
1575
1576    SkPath transformed;
1577    path->transform(transform, &transformed);
1578
1579    SkRegion clip;
1580    if (!mSnapshot->clipRegion->isEmpty()) {
1581        clip.setRegion(*mSnapshot->clipRegion);
1582    } else {
1583        Rect* bounds = mSnapshot->clipRect;
1584        clip.setRect(bounds->left, bounds->top, bounds->right, bounds->bottom);
1585    }
1586
1587    SkRegion region;
1588    region.setPath(transformed, clip);
1589
1590    bool clipped = mSnapshot->clipRegionTransformed(region, op);
1591    if (clipped) {
1592        dirtyClip();
1593    }
1594    return !mSnapshot->clipRect->isEmpty();
1595}
1596
1597bool OpenGLRenderer::clipRegion(SkRegion* region, SkRegion::Op op) {
1598    bool clipped = mSnapshot->clipRegionTransformed(*region, op);
1599    if (clipped) {
1600        dirtyClip();
1601    }
1602    return !mSnapshot->clipRect->isEmpty();
1603}
1604
1605Rect* OpenGLRenderer::getClipRect() {
1606    return mSnapshot->clipRect;
1607}
1608
1609///////////////////////////////////////////////////////////////////////////////
1610// Drawing commands
1611///////////////////////////////////////////////////////////////////////////////
1612
1613void OpenGLRenderer::setupDraw(bool clear) {
1614    // TODO: It would be best if we could do this before quickReject()
1615    //       changes the scissor test state
1616    if (clear) clearLayerRegions();
1617    // Make sure setScissor & setStencil happen at the beginning of
1618    // this method
1619    if (mDirtyClip) {
1620        if (mCaches.scissorEnabled) {
1621            setScissorFromClip();
1622        }
1623        setStencilFromClip();
1624    }
1625
1626    mDescription.reset();
1627
1628    mSetShaderColor = false;
1629    mColorSet = false;
1630    mColorA = mColorR = mColorG = mColorB = 0.0f;
1631    mTextureUnit = 0;
1632    mTrackDirtyRegions = true;
1633
1634    // Enable debug highlight when what we're about to draw is tested against
1635    // the stencil buffer and if stencil highlight debugging is on
1636    mDescription.hasDebugHighlight = !mCaches.debugOverdraw &&
1637            mCaches.debugStencilClip == Caches::kStencilShowHighlight &&
1638            mCaches.stencil.isTestEnabled();
1639}
1640
1641void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1642    mDescription.hasTexture = true;
1643    mDescription.hasAlpha8Texture = isAlpha8;
1644}
1645
1646void OpenGLRenderer::setupDrawWithTextureAndColor(bool isAlpha8) {
1647    mDescription.hasTexture = true;
1648    mDescription.hasColors = true;
1649    mDescription.hasAlpha8Texture = isAlpha8;
1650}
1651
1652void OpenGLRenderer::setupDrawWithExternalTexture() {
1653    mDescription.hasExternalTexture = true;
1654}
1655
1656void OpenGLRenderer::setupDrawNoTexture() {
1657    mCaches.disableTexCoordsVertexArray();
1658}
1659
1660void OpenGLRenderer::setupDrawAA() {
1661    mDescription.isAA = true;
1662}
1663
1664void OpenGLRenderer::setupDrawPoint(float pointSize) {
1665    mDescription.isPoint = true;
1666    mDescription.pointSize = pointSize;
1667}
1668
1669void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1670    mColorA = alpha / 255.0f;
1671    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1672    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1673    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1674    mColorSet = true;
1675    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
1676}
1677
1678void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1679    mColorA = alpha / 255.0f;
1680    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1681    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1682    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1683    mColorSet = true;
1684    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
1685}
1686
1687void OpenGLRenderer::setupDrawTextGamma(const SkPaint* paint) {
1688    mCaches.fontRenderer->describe(mDescription, paint);
1689}
1690
1691void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1692    mColorA = a;
1693    mColorR = r;
1694    mColorG = g;
1695    mColorB = b;
1696    mColorSet = true;
1697    mSetShaderColor = mDescription.setColor(r, g, b, a);
1698}
1699
1700void OpenGLRenderer::setupDrawShader() {
1701    if (mDrawModifiers.mShader) {
1702        mDrawModifiers.mShader->describe(mDescription, mExtensions);
1703    }
1704}
1705
1706void OpenGLRenderer::setupDrawColorFilter() {
1707    if (mDrawModifiers.mColorFilter) {
1708        mDrawModifiers.mColorFilter->describe(mDescription, mExtensions);
1709    }
1710}
1711
1712void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1713    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1714        mColorA = 1.0f;
1715        mColorR = mColorG = mColorB = 0.0f;
1716        mSetShaderColor = mDescription.modulate = true;
1717    }
1718}
1719
1720void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
1721    // When the blending mode is kClear_Mode, we need to use a modulate color
1722    // argb=1,0,0,0
1723    accountForClear(mode);
1724    bool blend = (mColorSet && mColorA < 1.0f) ||
1725            (mDrawModifiers.mShader && mDrawModifiers.mShader->blend());
1726    chooseBlending(blend, mode, mDescription, swapSrcDst);
1727}
1728
1729void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
1730    // When the blending mode is kClear_Mode, we need to use a modulate color
1731    // argb=1,0,0,0
1732    accountForClear(mode);
1733    blend |= (mColorSet && mColorA < 1.0f) ||
1734            (mDrawModifiers.mShader && mDrawModifiers.mShader->blend()) ||
1735            (mDrawModifiers.mColorFilter && mDrawModifiers.mColorFilter->blend());
1736    chooseBlending(blend, mode, mDescription, swapSrcDst);
1737}
1738
1739void OpenGLRenderer::setupDrawProgram() {
1740    useProgram(mCaches.programCache.get(mDescription));
1741}
1742
1743void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1744    mTrackDirtyRegions = false;
1745}
1746
1747void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
1748        bool ignoreTransform) {
1749    mModelView.loadTranslate(left, top, 0.0f);
1750    if (!ignoreTransform) {
1751        mCaches.currentProgram->set(mOrthoMatrix, mModelView, currentTransform());
1752        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, currentTransform());
1753    } else {
1754        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mat4::identity());
1755        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
1756    }
1757}
1758
1759void OpenGLRenderer::setupDrawModelViewIdentity(bool offset) {
1760    mCaches.currentProgram->set(mOrthoMatrix, mat4::identity(), currentTransform(), offset);
1761}
1762
1763void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
1764        bool ignoreTransform, bool ignoreModelView) {
1765    if (!ignoreModelView) {
1766        mModelView.loadTranslate(left, top, 0.0f);
1767        mModelView.scale(right - left, bottom - top, 1.0f);
1768    } else {
1769        mModelView.loadIdentity();
1770    }
1771    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1772    if (!ignoreTransform) {
1773        mCaches.currentProgram->set(mOrthoMatrix, mModelView, currentTransform());
1774        if (mTrackDirtyRegions && dirty) {
1775            dirtyLayer(left, top, right, bottom, currentTransform());
1776        }
1777    } else {
1778        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mat4::identity());
1779        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
1780    }
1781}
1782
1783void OpenGLRenderer::setupDrawPointUniforms() {
1784    int slot = mCaches.currentProgram->getUniform("pointSize");
1785    glUniform1f(slot, mDescription.pointSize);
1786}
1787
1788void OpenGLRenderer::setupDrawColorUniforms() {
1789    if ((mColorSet && !mDrawModifiers.mShader) || (mDrawModifiers.mShader && mSetShaderColor)) {
1790        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1791    }
1792}
1793
1794void OpenGLRenderer::setupDrawPureColorUniforms() {
1795    if (mSetShaderColor) {
1796        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1797    }
1798}
1799
1800void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1801    if (mDrawModifiers.mShader) {
1802        if (ignoreTransform) {
1803            mModelView.loadInverse(currentTransform());
1804        }
1805        mDrawModifiers.mShader->setupProgram(mCaches.currentProgram,
1806                mModelView, *mSnapshot, &mTextureUnit);
1807    }
1808}
1809
1810void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1811    if (mDrawModifiers.mShader) {
1812        mDrawModifiers.mShader->setupProgram(mCaches.currentProgram,
1813                mat4::identity(), *mSnapshot, &mTextureUnit);
1814    }
1815}
1816
1817void OpenGLRenderer::setupDrawColorFilterUniforms() {
1818    if (mDrawModifiers.mColorFilter) {
1819        mDrawModifiers.mColorFilter->setupProgram(mCaches.currentProgram);
1820    }
1821}
1822
1823void OpenGLRenderer::setupDrawTextGammaUniforms() {
1824    mCaches.fontRenderer->setupProgram(mDescription, mCaches.currentProgram);
1825}
1826
1827void OpenGLRenderer::setupDrawSimpleMesh() {
1828    bool force = mCaches.bindMeshBuffer();
1829    mCaches.bindPositionVertexPointer(force, 0);
1830    mCaches.unbindIndicesBuffer();
1831}
1832
1833void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1834    if (texture) bindTexture(texture);
1835    mTextureUnit++;
1836    mCaches.enableTexCoordsVertexArray();
1837}
1838
1839void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1840    bindExternalTexture(texture);
1841    mTextureUnit++;
1842    mCaches.enableTexCoordsVertexArray();
1843}
1844
1845void OpenGLRenderer::setupDrawTextureTransform() {
1846    mDescription.hasTextureTransform = true;
1847}
1848
1849void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1850    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1851            GL_FALSE, &transform.data[0]);
1852}
1853
1854void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1855    bool force = false;
1856    if (!vertices) {
1857        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1858    } else {
1859        force = mCaches.unbindMeshBuffer();
1860    }
1861
1862    mCaches.bindPositionVertexPointer(force, vertices);
1863    if (mCaches.currentProgram->texCoords >= 0) {
1864        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1865    }
1866
1867    mCaches.unbindIndicesBuffer();
1868}
1869
1870void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLvoid* colors) {
1871    bool force = mCaches.unbindMeshBuffer();
1872    GLsizei stride = sizeof(ColorTextureVertex);
1873
1874    mCaches.bindPositionVertexPointer(force, vertices, stride);
1875    if (mCaches.currentProgram->texCoords >= 0) {
1876        mCaches.bindTexCoordsVertexPointer(force, texCoords, stride);
1877    }
1878    int slot = mCaches.currentProgram->getAttrib("colors");
1879    if (slot >= 0) {
1880        glEnableVertexAttribArray(slot);
1881        glVertexAttribPointer(slot, 4, GL_FLOAT, GL_FALSE, stride, colors);
1882    }
1883
1884    mCaches.unbindIndicesBuffer();
1885}
1886
1887void OpenGLRenderer::setupDrawMeshIndices(GLvoid* vertices, GLvoid* texCoords) {
1888    bool force = mCaches.unbindMeshBuffer();
1889    mCaches.bindPositionVertexPointer(force, vertices);
1890    if (mCaches.currentProgram->texCoords >= 0) {
1891        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1892    }
1893}
1894
1895void OpenGLRenderer::setupDrawVertices(GLvoid* vertices) {
1896    bool force = mCaches.unbindMeshBuffer();
1897    mCaches.bindPositionVertexPointer(force, vertices, gVertexStride);
1898    mCaches.unbindIndicesBuffer();
1899}
1900
1901void OpenGLRenderer::finishDrawTexture() {
1902}
1903
1904///////////////////////////////////////////////////////////////////////////////
1905// Drawing
1906///////////////////////////////////////////////////////////////////////////////
1907
1908status_t OpenGLRenderer::drawDisplayList(DisplayList* displayList, Rect& dirty,
1909        int32_t replayFlags) {
1910    status_t status;
1911    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1912    // will be performed by the display list itself
1913    if (displayList && displayList->isRenderable()) {
1914        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
1915            status = startFrame();
1916            ReplayStateStruct replayStruct(*this, dirty, replayFlags);
1917            displayList->replay(replayStruct, 0);
1918            return status | replayStruct.mDrawGlStatus;
1919        }
1920
1921        DeferredDisplayList deferredList;
1922        DeferStateStruct deferStruct(deferredList, *this, replayFlags);
1923        displayList->defer(deferStruct, 0);
1924
1925        flushLayers();
1926        status = startFrame();
1927
1928        return status | deferredList.flush(*this, dirty);
1929    }
1930
1931    return DrawGlInfo::kStatusDone;
1932}
1933
1934void OpenGLRenderer::outputDisplayList(DisplayList* displayList) {
1935    if (displayList) {
1936        displayList->output(1);
1937    }
1938}
1939
1940void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, SkPaint* paint) {
1941    int alpha;
1942    SkXfermode::Mode mode;
1943    getAlphaAndMode(paint, &alpha, &mode);
1944
1945    int color = paint != NULL ? paint->getColor() : 0;
1946
1947    float x = left;
1948    float y = top;
1949
1950    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1951
1952    bool ignoreTransform = false;
1953    if (currentTransform().isPureTranslate()) {
1954        x = (int) floorf(left + currentTransform().getTranslateX() + 0.5f);
1955        y = (int) floorf(top + currentTransform().getTranslateY() + 0.5f);
1956        ignoreTransform = true;
1957
1958        texture->setFilter(GL_NEAREST, true);
1959    } else {
1960        texture->setFilter(FILTER(paint), true);
1961    }
1962
1963    drawAlpha8TextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1964            paint != NULL, color, alpha, mode, (GLvoid*) NULL,
1965            (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
1966}
1967
1968status_t OpenGLRenderer::drawBitmaps(SkBitmap* bitmap, int bitmapCount, TextureVertex* vertices,
1969        const Rect& bounds, SkPaint* paint) {
1970
1971    // merged draw operations don't need scissor, but clip should still be valid
1972    mCaches.setScissorEnabled(mScissorOptimizationDisabled);
1973
1974    mCaches.activeTexture(0);
1975    Texture* texture = mCaches.textureCache.get(bitmap);
1976    if (!texture) return DrawGlInfo::kStatusDone;
1977    const AutoTexture autoCleanup(texture);
1978
1979    int alpha;
1980    SkXfermode::Mode mode;
1981    getAlphaAndMode(paint, &alpha, &mode);
1982
1983    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1984    texture->setFilter(GL_NEAREST, true); // merged ops are always pure-translation for now
1985
1986    const float x = (int) floorf(bounds.left + 0.5f);
1987    const float y = (int) floorf(bounds.top + 0.5f);
1988    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
1989        int color = paint != NULL ? paint->getColor() : 0;
1990        drawAlpha8TextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1991                texture->id, paint != NULL, color, alpha, mode,
1992                &vertices[0].position[0], &vertices[0].texture[0],
1993                GL_TRIANGLES, bitmapCount * 6, true, true);
1994    } else {
1995        drawTextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1996                texture->id, alpha / 255.0f, mode, texture->blend,
1997                &vertices[0].position[0], &vertices[0].texture[0],
1998                GL_TRIANGLES, bitmapCount * 6, false, true, 0, true);
1999    }
2000
2001    return DrawGlInfo::kStatusDrew;
2002}
2003
2004status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
2005    const float right = left + bitmap->width();
2006    const float bottom = top + bitmap->height();
2007
2008    if (quickReject(left, top, right, bottom)) {
2009        return DrawGlInfo::kStatusDone;
2010    }
2011
2012    mCaches.activeTexture(0);
2013    Texture* texture = mCaches.textureCache.get(bitmap);
2014    if (!texture) return DrawGlInfo::kStatusDone;
2015    const AutoTexture autoCleanup(texture);
2016
2017    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
2018        drawAlphaBitmap(texture, left, top, paint);
2019    } else {
2020        drawTextureRect(left, top, right, bottom, texture, paint);
2021    }
2022
2023    return DrawGlInfo::kStatusDrew;
2024}
2025
2026status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
2027    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
2028    const mat4 transform(*matrix);
2029    transform.mapRect(r);
2030
2031    if (quickReject(r.left, r.top, r.right, r.bottom)) {
2032        return DrawGlInfo::kStatusDone;
2033    }
2034
2035    mCaches.activeTexture(0);
2036    Texture* texture = mCaches.textureCache.get(bitmap);
2037    if (!texture) return DrawGlInfo::kStatusDone;
2038    const AutoTexture autoCleanup(texture);
2039
2040    // This could be done in a cheaper way, all we need is pass the matrix
2041    // to the vertex shader. The save/restore is a bit overkill.
2042    save(SkCanvas::kMatrix_SaveFlag);
2043    concatMatrix(matrix);
2044    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
2045        drawAlphaBitmap(texture, 0.0f, 0.0f, paint);
2046    } else {
2047        drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
2048    }
2049    restore();
2050
2051    return DrawGlInfo::kStatusDrew;
2052}
2053
2054status_t OpenGLRenderer::drawBitmapData(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
2055    const float right = left + bitmap->width();
2056    const float bottom = top + bitmap->height();
2057
2058    if (quickReject(left, top, right, bottom)) {
2059        return DrawGlInfo::kStatusDone;
2060    }
2061
2062    mCaches.activeTexture(0);
2063    Texture* texture = mCaches.textureCache.getTransient(bitmap);
2064    const AutoTexture autoCleanup(texture);
2065
2066    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
2067        drawAlphaBitmap(texture, left, top, paint);
2068    } else {
2069        drawTextureRect(left, top, right, bottom, texture, paint);
2070    }
2071
2072    return DrawGlInfo::kStatusDrew;
2073}
2074
2075status_t OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
2076        float* vertices, int* colors, SkPaint* paint) {
2077    if (!vertices || mSnapshot->isIgnored()) {
2078        return DrawGlInfo::kStatusDone;
2079    }
2080
2081    float left = FLT_MAX;
2082    float top = FLT_MAX;
2083    float right = FLT_MIN;
2084    float bottom = FLT_MIN;
2085
2086    const uint32_t count = meshWidth * meshHeight * 6;
2087
2088    ColorTextureVertex mesh[count];
2089    ColorTextureVertex* vertex = mesh;
2090
2091    bool cleanupColors = false;
2092    if (!colors) {
2093        uint32_t colorsCount = (meshWidth + 1) * (meshHeight + 1);
2094        colors = new int[colorsCount];
2095        memset(colors, 0xff, colorsCount * sizeof(int));
2096        cleanupColors = true;
2097    }
2098
2099    for (int32_t y = 0; y < meshHeight; y++) {
2100        for (int32_t x = 0; x < meshWidth; x++) {
2101            uint32_t i = (y * (meshWidth + 1) + x) * 2;
2102
2103            float u1 = float(x) / meshWidth;
2104            float u2 = float(x + 1) / meshWidth;
2105            float v1 = float(y) / meshHeight;
2106            float v2 = float(y + 1) / meshHeight;
2107
2108            int ax = i + (meshWidth + 1) * 2;
2109            int ay = ax + 1;
2110            int bx = i;
2111            int by = bx + 1;
2112            int cx = i + 2;
2113            int cy = cx + 1;
2114            int dx = i + (meshWidth + 1) * 2 + 2;
2115            int dy = dx + 1;
2116
2117            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2118            ColorTextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2, colors[ax / 2]);
2119            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2120
2121            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2122            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2123            ColorTextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1, colors[cx / 2]);
2124
2125            left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
2126            top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
2127            right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
2128            bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
2129        }
2130    }
2131
2132    if (quickReject(left, top, right, bottom)) {
2133        if (cleanupColors) delete[] colors;
2134        return DrawGlInfo::kStatusDone;
2135    }
2136
2137    mCaches.activeTexture(0);
2138    Texture* texture = mCaches.textureCache.get(bitmap);
2139    if (!texture) {
2140        if (cleanupColors) delete[] colors;
2141        return DrawGlInfo::kStatusDone;
2142    }
2143    const AutoTexture autoCleanup(texture);
2144
2145    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2146    texture->setFilter(FILTER(paint), true);
2147
2148    int alpha;
2149    SkXfermode::Mode mode;
2150    getAlphaAndMode(paint, &alpha, &mode);
2151
2152    float a = alpha / 255.0f;
2153
2154    if (hasLayer()) {
2155        dirtyLayer(left, top, right, bottom, currentTransform());
2156    }
2157
2158    setupDraw();
2159    setupDrawWithTextureAndColor();
2160    setupDrawColor(a, a, a, a);
2161    setupDrawColorFilter();
2162    setupDrawBlending(true, mode, false);
2163    setupDrawProgram();
2164    setupDrawDirtyRegionsDisabled();
2165    setupDrawModelView(0.0f, 0.0f, 1.0f, 1.0f, false);
2166    setupDrawTexture(texture->id);
2167    setupDrawPureColorUniforms();
2168    setupDrawColorFilterUniforms();
2169    setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0], &mesh[0].color[0]);
2170
2171    glDrawArrays(GL_TRIANGLES, 0, count);
2172
2173    finishDrawTexture();
2174
2175    int slot = mCaches.currentProgram->getAttrib("colors");
2176    if (slot >= 0) {
2177        glDisableVertexAttribArray(slot);
2178    }
2179
2180    if (cleanupColors) delete[] colors;
2181
2182    return DrawGlInfo::kStatusDrew;
2183}
2184
2185status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
2186         float srcLeft, float srcTop, float srcRight, float srcBottom,
2187         float dstLeft, float dstTop, float dstRight, float dstBottom,
2188         SkPaint* paint) {
2189    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
2190        return DrawGlInfo::kStatusDone;
2191    }
2192
2193    mCaches.activeTexture(0);
2194    Texture* texture = mCaches.textureCache.get(bitmap);
2195    if (!texture) return DrawGlInfo::kStatusDone;
2196    const AutoTexture autoCleanup(texture);
2197
2198    const float width = texture->width;
2199    const float height = texture->height;
2200
2201    const float u1 = fmax(0.0f, srcLeft / width);
2202    const float v1 = fmax(0.0f, srcTop / height);
2203    const float u2 = fmin(1.0f, srcRight / width);
2204    const float v2 = fmin(1.0f, srcBottom / height);
2205
2206    mCaches.unbindMeshBuffer();
2207    resetDrawTextureTexCoords(u1, v1, u2, v2);
2208
2209    int alpha;
2210    SkXfermode::Mode mode;
2211    getAlphaAndMode(paint, &alpha, &mode);
2212
2213    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2214
2215    float scaleX = (dstRight - dstLeft) / (srcRight - srcLeft);
2216    float scaleY = (dstBottom - dstTop) / (srcBottom - srcTop);
2217
2218    bool scaled = scaleX != 1.0f || scaleY != 1.0f;
2219    // Apply a scale transform on the canvas only when a shader is in use
2220    // Skia handles the ratio between the dst and src rects as a scale factor
2221    // when a shader is set
2222    bool useScaleTransform = mDrawModifiers.mShader && scaled;
2223    bool ignoreTransform = false;
2224
2225    if (CC_LIKELY(currentTransform().isPureTranslate() && !useScaleTransform)) {
2226        float x = (int) floorf(dstLeft + currentTransform().getTranslateX() + 0.5f);
2227        float y = (int) floorf(dstTop + currentTransform().getTranslateY() + 0.5f);
2228
2229        dstRight = x + (dstRight - dstLeft);
2230        dstBottom = y + (dstBottom - dstTop);
2231
2232        dstLeft = x;
2233        dstTop = y;
2234
2235        texture->setFilter(scaled ? FILTER(paint) : GL_NEAREST, true);
2236        ignoreTransform = true;
2237    } else {
2238        texture->setFilter(FILTER(paint), true);
2239    }
2240
2241    if (CC_UNLIKELY(useScaleTransform)) {
2242        save(SkCanvas::kMatrix_SaveFlag);
2243        translate(dstLeft, dstTop);
2244        scale(scaleX, scaleY);
2245
2246        dstLeft = 0.0f;
2247        dstTop = 0.0f;
2248
2249        dstRight = srcRight - srcLeft;
2250        dstBottom = srcBottom - srcTop;
2251    }
2252
2253    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
2254        int color = paint ? paint->getColor() : 0;
2255        drawAlpha8TextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2256                texture->id, paint != NULL, color, alpha, mode,
2257                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
2258                GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
2259    } else {
2260        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2261                texture->id, alpha / 255.0f, mode, texture->blend,
2262                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
2263                GL_TRIANGLE_STRIP, gMeshCount, false, ignoreTransform);
2264    }
2265
2266    if (CC_UNLIKELY(useScaleTransform)) {
2267        restore();
2268    }
2269
2270    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
2271
2272    return DrawGlInfo::kStatusDrew;
2273}
2274
2275status_t OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
2276        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
2277        float left, float top, float right, float bottom, SkPaint* paint) {
2278    int alpha;
2279    SkXfermode::Mode mode;
2280    getAlphaAndMode(paint, &alpha, &mode);
2281
2282    return drawPatch(bitmap, xDivs, yDivs, colors, width, height, numColors,
2283            left, top, right, bottom, alpha, mode);
2284}
2285
2286status_t OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
2287        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
2288        float left, float top, float right, float bottom, int alpha, SkXfermode::Mode mode) {
2289    if (quickReject(left, top, right, bottom)) {
2290        return DrawGlInfo::kStatusDone;
2291    }
2292
2293    alpha *= mSnapshot->alpha;
2294
2295    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
2296            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
2297
2298    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
2299        mCaches.activeTexture(0);
2300        Texture* texture = mCaches.textureCache.get(bitmap);
2301        if (!texture) return DrawGlInfo::kStatusDone;
2302        const AutoTexture autoCleanup(texture);
2303        texture->setWrap(GL_CLAMP_TO_EDGE, true);
2304        texture->setFilter(GL_LINEAR, true);
2305
2306        const bool pureTranslate = currentTransform().isPureTranslate();
2307        // Mark the current layer dirty where we are going to draw the patch
2308        if (hasLayer() && mesh->hasEmptyQuads) {
2309            const float offsetX = left + currentTransform().getTranslateX();
2310            const float offsetY = top + currentTransform().getTranslateY();
2311            const size_t count = mesh->quads.size();
2312            for (size_t i = 0; i < count; i++) {
2313                const Rect& bounds = mesh->quads.itemAt(i);
2314                if (CC_LIKELY(pureTranslate)) {
2315                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
2316                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
2317                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
2318                } else {
2319                    dirtyLayer(left + bounds.left, top + bounds.top,
2320                            left + bounds.right, top + bounds.bottom, currentTransform());
2321                }
2322            }
2323        }
2324
2325        if (CC_LIKELY(pureTranslate)) {
2326            const float x = (int) floorf(left + currentTransform().getTranslateX() + 0.5f);
2327            const float y = (int) floorf(top + currentTransform().getTranslateY() + 0.5f);
2328
2329            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
2330                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
2331                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
2332                    true, !mesh->hasEmptyQuads);
2333        } else {
2334            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
2335                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
2336                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
2337                    true, !mesh->hasEmptyQuads);
2338        }
2339    }
2340
2341    return DrawGlInfo::kStatusDrew;
2342}
2343
2344status_t OpenGLRenderer::drawVertexBuffer(const VertexBuffer& vertexBuffer, SkPaint* paint,
2345        bool useOffset) {
2346    if (!vertexBuffer.getSize()) {
2347        // no vertices to draw
2348        return DrawGlInfo::kStatusDone;
2349    }
2350
2351    int color = paint->getColor();
2352    SkXfermode::Mode mode = getXfermode(paint->getXfermode());
2353    bool isAA = paint->isAntiAlias();
2354
2355    setupDraw();
2356    setupDrawNoTexture();
2357    if (isAA) setupDrawAA();
2358    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
2359    setupDrawColorFilter();
2360    setupDrawShader();
2361    setupDrawBlending(isAA, mode);
2362    setupDrawProgram();
2363    setupDrawModelViewIdentity(useOffset);
2364    setupDrawColorUniforms();
2365    setupDrawColorFilterUniforms();
2366    setupDrawShaderIdentityUniforms();
2367
2368    void* vertices = vertexBuffer.getBuffer();
2369    bool force = mCaches.unbindMeshBuffer();
2370    mCaches.bindPositionVertexPointer(true, vertices, isAA ? gAlphaVertexStride : gVertexStride);
2371    mCaches.resetTexCoordsVertexPointer();
2372    mCaches.unbindIndicesBuffer();
2373
2374    int alphaSlot = -1;
2375    if (isAA) {
2376        void* alphaCoords = ((GLbyte*) vertices) + gVertexAlphaOffset;
2377        alphaSlot = mCaches.currentProgram->getAttrib("vtxAlpha");
2378
2379        // TODO: avoid enable/disable in back to back uses of the alpha attribute
2380        glEnableVertexAttribArray(alphaSlot);
2381        glVertexAttribPointer(alphaSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, alphaCoords);
2382    }
2383
2384    glDrawArrays(GL_TRIANGLE_STRIP, 0, vertexBuffer.getSize());
2385
2386    if (isAA) {
2387        glDisableVertexAttribArray(alphaSlot);
2388    }
2389
2390    return DrawGlInfo::kStatusDrew;
2391}
2392
2393/**
2394 * Renders a convex path via tessellation. For AA paths, this function uses a similar approach to
2395 * that of AA lines in the drawLines() function.  We expand the convex path by a half pixel in
2396 * screen space in all directions. However, instead of using a fragment shader to compute the
2397 * translucency of the color from its position, we simply use a varying parameter to define how far
2398 * a given pixel is from the edge. For non-AA paths, the expansion and alpha varying are not used.
2399 *
2400 * Doesn't yet support joins, caps, or path effects.
2401 */
2402status_t OpenGLRenderer::drawConvexPath(const SkPath& path, SkPaint* paint) {
2403    VertexBuffer vertexBuffer;
2404    // TODO: try clipping large paths to viewport
2405    PathTessellator::tessellatePath(path, paint, mSnapshot->transform, vertexBuffer);
2406
2407    if (hasLayer()) {
2408        SkRect bounds = path.getBounds();
2409        PathTessellator::expandBoundsForStroke(bounds, paint, false);
2410        dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, currentTransform());
2411    }
2412
2413    return drawVertexBuffer(vertexBuffer, paint);
2414}
2415
2416/**
2417 * We create tristrips for the lines much like shape stroke tessellation, using a per-vertex alpha
2418 * and additional geometry for defining an alpha slope perimeter.
2419 *
2420 * Using GL_LINES can be difficult because the rasterization rules for those lines produces some
2421 * unexpected results, and may vary between hardware devices. Previously we used a varying-base
2422 * in-shader alpha region, but found it to be taxing on some GPUs.
2423 *
2424 * TODO: try using a fixed input buffer for non-capped lines as in text rendering. this may reduce
2425 * memory transfer by removing need for degenerate vertices.
2426 */
2427status_t OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
2428    if (mSnapshot->isIgnored() || count < 4) return DrawGlInfo::kStatusDone;
2429
2430    count &= ~0x3; // round down to nearest four
2431
2432    VertexBuffer buffer;
2433    SkRect bounds;
2434    PathTessellator::tessellateLines(points, count, paint, mSnapshot->transform, bounds, buffer);
2435
2436    if (quickReject(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom)) {
2437        return DrawGlInfo::kStatusDone;
2438    }
2439
2440    dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, currentTransform());
2441
2442    bool useOffset = !paint->isAntiAlias();
2443    return drawVertexBuffer(buffer, paint, useOffset);
2444}
2445
2446status_t OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) {
2447    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2448
2449    // TODO: The paint's cap style defines whether the points are square or circular
2450    // TODO: Handle AA for round points
2451
2452    // A stroke width of 0 has a special meaning in Skia:
2453    // it draws an unscaled 1px point
2454    float strokeWidth = paint->getStrokeWidth();
2455    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
2456    if (isHairLine) {
2457        // Now that we know it's hairline, we can set the effective width, to be used later
2458        strokeWidth = 1.0f;
2459    }
2460    const float halfWidth = strokeWidth / 2;
2461
2462    int alpha;
2463    SkXfermode::Mode mode;
2464    getAlphaAndMode(paint, &alpha, &mode);
2465
2466    int verticesCount = count >> 1;
2467    int generatedVerticesCount = 0;
2468
2469    TextureVertex pointsData[verticesCount];
2470    TextureVertex* vertex = &pointsData[0];
2471
2472    // TODO: We should optimize this method to not generate vertices for points
2473    // that lie outside of the clip.
2474    mCaches.enableScissor();
2475
2476    setupDraw();
2477    setupDrawNoTexture();
2478    setupDrawPoint(strokeWidth);
2479    setupDrawColor(paint->getColor(), alpha);
2480    setupDrawColorFilter();
2481    setupDrawShader();
2482    setupDrawBlending(mode);
2483    setupDrawProgram();
2484    setupDrawModelViewIdentity(true);
2485    setupDrawColorUniforms();
2486    setupDrawColorFilterUniforms();
2487    setupDrawPointUniforms();
2488    setupDrawShaderIdentityUniforms();
2489    setupDrawMesh(vertex);
2490
2491    for (int i = 0; i < count; i += 2) {
2492        TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
2493        generatedVerticesCount++;
2494
2495        float left = points[i] - halfWidth;
2496        float right = points[i] + halfWidth;
2497        float top = points[i + 1] - halfWidth;
2498        float bottom = points [i + 1] + halfWidth;
2499
2500        dirtyLayer(left, top, right, bottom, currentTransform());
2501    }
2502
2503    glDrawArrays(GL_POINTS, 0, generatedVerticesCount);
2504
2505    return DrawGlInfo::kStatusDrew;
2506}
2507
2508status_t OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
2509    // No need to check against the clip, we fill the clip region
2510    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2511
2512    Rect& clip(*mSnapshot->clipRect);
2513    clip.snapToPixelBoundaries();
2514
2515    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
2516
2517    return DrawGlInfo::kStatusDrew;
2518}
2519
2520status_t OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture,
2521        SkPaint* paint) {
2522    if (!texture) return DrawGlInfo::kStatusDone;
2523    const AutoTexture autoCleanup(texture);
2524
2525    const float x = left + texture->left - texture->offset;
2526    const float y = top + texture->top - texture->offset;
2527
2528    drawPathTexture(texture, x, y, paint);
2529
2530    return DrawGlInfo::kStatusDrew;
2531}
2532
2533status_t OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
2534        float rx, float ry, SkPaint* p) {
2535    if (mSnapshot->isIgnored() || quickRejectPreStroke(left, top, right, bottom, p) ||
2536            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2537        return DrawGlInfo::kStatusDone;
2538    }
2539
2540    if (p->getPathEffect() != 0) {
2541        mCaches.activeTexture(0);
2542        const PathTexture* texture = mCaches.pathCache.getRoundRect(
2543                right - left, bottom - top, rx, ry, p);
2544        return drawShape(left, top, texture, p);
2545    }
2546
2547    SkPath path;
2548    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2549    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2550        float outset = p->getStrokeWidth() / 2;
2551        rect.outset(outset, outset);
2552        rx += outset;
2553        ry += outset;
2554    }
2555    path.addRoundRect(rect, rx, ry);
2556    return drawConvexPath(path, p);
2557}
2558
2559status_t OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* p) {
2560    if (mSnapshot->isIgnored() || quickRejectPreStroke(x - radius, y - radius,
2561            x + radius, y + radius, p) ||
2562            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2563        return DrawGlInfo::kStatusDone;
2564    }
2565    if (p->getPathEffect() != 0) {
2566        mCaches.activeTexture(0);
2567        const PathTexture* texture = mCaches.pathCache.getCircle(radius, p);
2568        return drawShape(x - radius, y - radius, texture, p);
2569    }
2570
2571    SkPath path;
2572    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2573        path.addCircle(x, y, radius + p->getStrokeWidth() / 2);
2574    } else {
2575        path.addCircle(x, y, radius);
2576    }
2577    return drawConvexPath(path, p);
2578}
2579
2580status_t OpenGLRenderer::drawOval(float left, float top, float right, float bottom,
2581        SkPaint* p) {
2582    if (mSnapshot->isIgnored() || quickRejectPreStroke(left, top, right, bottom, p) ||
2583            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2584        return DrawGlInfo::kStatusDone;
2585    }
2586
2587    if (p->getPathEffect() != 0) {
2588        mCaches.activeTexture(0);
2589        const PathTexture* texture = mCaches.pathCache.getOval(right - left, bottom - top, p);
2590        return drawShape(left, top, texture, p);
2591    }
2592
2593    SkPath path;
2594    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2595    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2596        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2597    }
2598    path.addOval(rect);
2599    return drawConvexPath(path, p);
2600}
2601
2602status_t OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2603        float startAngle, float sweepAngle, bool useCenter, SkPaint* p) {
2604    if (mSnapshot->isIgnored() || quickRejectPreStroke(left, top, right, bottom, p) ||
2605            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2606        return DrawGlInfo::kStatusDone;
2607    }
2608
2609    if (fabs(sweepAngle) >= 360.0f) {
2610        return drawOval(left, top, right, bottom, p);
2611    }
2612
2613    // TODO: support fills (accounting for concavity if useCenter && sweepAngle > 180)
2614    if (p->getStyle() != SkPaint::kStroke_Style || p->getPathEffect() != 0 || useCenter) {
2615        mCaches.activeTexture(0);
2616        const PathTexture* texture = mCaches.pathCache.getArc(right - left, bottom - top,
2617                startAngle, sweepAngle, useCenter, p);
2618        return drawShape(left, top, texture, p);
2619    }
2620
2621    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2622    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2623        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2624    }
2625
2626    SkPath path;
2627    if (useCenter) {
2628        path.moveTo(rect.centerX(), rect.centerY());
2629    }
2630    path.arcTo(rect, startAngle, sweepAngle, !useCenter);
2631    if (useCenter) {
2632        path.close();
2633    }
2634    return drawConvexPath(path, p);
2635}
2636
2637// See SkPaintDefaults.h
2638#define SkPaintDefaults_MiterLimit SkIntToScalar(4)
2639
2640status_t OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
2641    if (mSnapshot->isIgnored() || quickRejectPreStroke(left, top, right, bottom, p) ||
2642            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2643        return DrawGlInfo::kStatusDone;
2644    }
2645
2646    if (p->getStyle() != SkPaint::kFill_Style) {
2647        // only fill style is supported by drawConvexPath, since others have to handle joins
2648        if (p->getPathEffect() != 0 || p->getStrokeJoin() != SkPaint::kMiter_Join ||
2649                p->getStrokeMiter() != SkPaintDefaults_MiterLimit) {
2650            mCaches.activeTexture(0);
2651            const PathTexture* texture =
2652                    mCaches.pathCache.getRect(right - left, bottom - top, p);
2653            return drawShape(left, top, texture, p);
2654        }
2655
2656        SkPath path;
2657        SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2658        if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2659            rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2660        }
2661        path.addRect(rect);
2662        return drawConvexPath(path, p);
2663    }
2664
2665    if (p->isAntiAlias() && !currentTransform().isSimple()) {
2666        SkPath path;
2667        path.addRect(left, top, right, bottom);
2668        return drawConvexPath(path, p);
2669    } else {
2670        drawColorRect(left, top, right, bottom, p->getColor(), getXfermode(p->getXfermode()));
2671        return DrawGlInfo::kStatusDrew;
2672    }
2673}
2674
2675void OpenGLRenderer::drawTextShadow(SkPaint* paint, const char* text, int bytesCount, int count,
2676        const float* positions, FontRenderer& fontRenderer, int alpha, SkXfermode::Mode mode,
2677        float x, float y) {
2678    mCaches.activeTexture(0);
2679
2680    // NOTE: The drop shadow will not perform gamma correction
2681    //       if shader-based correction is enabled
2682    mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2683    const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2684            paint, text, bytesCount, count, mDrawModifiers.mShadowRadius, positions);
2685    // If the drop shadow exceeds the max texture size or couldn't be
2686    // allocated, skip drawing
2687    if (!shadow) return;
2688    const AutoTexture autoCleanup(shadow);
2689
2690    const float sx = x - shadow->left + mDrawModifiers.mShadowDx;
2691    const float sy = y - shadow->top + mDrawModifiers.mShadowDy;
2692
2693    const int shadowAlpha = ((mDrawModifiers.mShadowColor >> 24) & 0xFF) * mSnapshot->alpha;
2694    int shadowColor = mDrawModifiers.mShadowColor;
2695    if (mDrawModifiers.mShader) {
2696        shadowColor = 0xffffffff;
2697    }
2698
2699    setupDraw();
2700    setupDrawWithTexture(true);
2701    setupDrawAlpha8Color(shadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
2702    setupDrawColorFilter();
2703    setupDrawShader();
2704    setupDrawBlending(true, mode);
2705    setupDrawProgram();
2706    setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height);
2707    setupDrawTexture(shadow->id);
2708    setupDrawPureColorUniforms();
2709    setupDrawColorFilterUniforms();
2710    setupDrawShaderUniforms();
2711    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2712
2713    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2714}
2715
2716bool OpenGLRenderer::canSkipText(const SkPaint* paint) const {
2717    float alpha = (mDrawModifiers.mHasShadow ? 1.0f : paint->getAlpha()) * mSnapshot->alpha;
2718    return alpha == 0.0f && getXfermode(paint->getXfermode()) == SkXfermode::kSrcOver_Mode;
2719}
2720
2721class TextSetupFunctor: public Functor {
2722public:
2723    TextSetupFunctor(OpenGLRenderer& renderer, float x, float y, bool pureTranslate,
2724            int alpha, SkXfermode::Mode mode, SkPaint* paint): Functor(),
2725            renderer(renderer), x(x), y(y), pureTranslate(pureTranslate),
2726            alpha(alpha), mode(mode), paint(paint) {
2727    }
2728    ~TextSetupFunctor() { }
2729
2730    status_t operator ()(int what, void* data) {
2731        renderer.setupDraw();
2732        renderer.setupDrawTextGamma(paint);
2733        renderer.setupDrawDirtyRegionsDisabled();
2734        renderer.setupDrawWithTexture(true);
2735        renderer.setupDrawAlpha8Color(paint->getColor(), alpha);
2736        renderer.setupDrawColorFilter();
2737        renderer.setupDrawShader();
2738        renderer.setupDrawBlending(true, mode);
2739        renderer.setupDrawProgram();
2740        renderer.setupDrawModelView(x, y, x, y, pureTranslate, true);
2741        // Calling setupDrawTexture with the name 0 will enable the
2742        // uv attributes and increase the texture unit count
2743        // texture binding will be performed by the font renderer as
2744        // needed
2745        renderer.setupDrawTexture(0);
2746        renderer.setupDrawPureColorUniforms();
2747        renderer.setupDrawColorFilterUniforms();
2748        renderer.setupDrawShaderUniforms(pureTranslate);
2749        renderer.setupDrawTextGammaUniforms();
2750
2751        return NO_ERROR;
2752    }
2753
2754    OpenGLRenderer& renderer;
2755    float x;
2756    float y;
2757    bool pureTranslate;
2758    int alpha;
2759    SkXfermode::Mode mode;
2760    SkPaint* paint;
2761};
2762
2763status_t OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2764        const float* positions, SkPaint* paint) {
2765    if (text == NULL || count == 0 || mSnapshot->isIgnored() || canSkipText(paint)) {
2766        return DrawGlInfo::kStatusDone;
2767    }
2768
2769    // NOTE: Skia does not support perspective transform on drawPosText yet
2770    if (!currentTransform().isSimple()) {
2771        return DrawGlInfo::kStatusDone;
2772    }
2773
2774    float x = 0.0f;
2775    float y = 0.0f;
2776    const bool pureTranslate = currentTransform().isPureTranslate();
2777    if (pureTranslate) {
2778        x = (int) floorf(x + currentTransform().getTranslateX() + 0.5f);
2779        y = (int) floorf(y + currentTransform().getTranslateY() + 0.5f);
2780    }
2781
2782    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2783    fontRenderer.setFont(paint, mat4::identity());
2784
2785    int alpha;
2786    SkXfermode::Mode mode;
2787    getAlphaAndMode(paint, &alpha, &mode);
2788
2789    if (CC_UNLIKELY(mDrawModifiers.mHasShadow)) {
2790        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2791                alpha, mode, 0.0f, 0.0f);
2792    }
2793
2794    // Pick the appropriate texture filtering
2795    bool linearFilter = currentTransform().changesBounds();
2796    if (pureTranslate && !linearFilter) {
2797        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2798    }
2799    fontRenderer.setTextureFiltering(linearFilter);
2800
2801    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2802    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2803
2804    const bool hasActiveLayer = hasLayer();
2805
2806    TextSetupFunctor functor(*this, x, y, pureTranslate, alpha, mode, paint);
2807    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2808            positions, hasActiveLayer ? &bounds : NULL, &functor)) {
2809        if (hasActiveLayer) {
2810            if (!pureTranslate) {
2811                currentTransform().mapRect(bounds);
2812            }
2813            dirtyLayerUnchecked(bounds, getRegion());
2814        }
2815    }
2816
2817    return DrawGlInfo::kStatusDrew;
2818}
2819
2820mat4 OpenGLRenderer::findBestFontTransform(const mat4& transform) const {
2821    mat4 fontTransform;
2822    if (CC_LIKELY(transform.isPureTranslate())) {
2823        fontTransform = mat4::identity();
2824    } else {
2825        if (CC_UNLIKELY(transform.isPerspective())) {
2826            fontTransform = mat4::identity();
2827        } else {
2828            float sx, sy;
2829            currentTransform().decomposeScale(sx, sy);
2830            fontTransform.loadScale(sx, sy, 1.0f);
2831        }
2832    }
2833    return fontTransform;
2834}
2835
2836status_t OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
2837        float x, float y, const float* positions, SkPaint* paint, float length,
2838        DrawOpMode drawOpMode) {
2839
2840    if (drawOpMode == kDrawOpMode_Immediate &&
2841            (text == NULL || count == 0 || mSnapshot->isIgnored() || canSkipText(paint))) {
2842        return DrawGlInfo::kStatusDone;
2843    }
2844
2845    if (length < 0.0f) length = paint->measureText(text, bytesCount);
2846    switch (paint->getTextAlign()) {
2847        case SkPaint::kCenter_Align:
2848            x -= length / 2.0f;
2849            break;
2850        case SkPaint::kRight_Align:
2851            x -= length;
2852            break;
2853        default:
2854            break;
2855    }
2856
2857    SkPaint::FontMetrics metrics;
2858    paint->getFontMetrics(&metrics, 0.0f);
2859    if (drawOpMode == kDrawOpMode_Immediate) {
2860        if (quickReject(x, y + metrics.fTop, x + length, y + metrics.fBottom)) {
2861            return DrawGlInfo::kStatusDone;
2862        }
2863    } else {
2864        // merged draw operations don't need scissor, but clip should still be valid
2865        mCaches.setScissorEnabled(mScissorOptimizationDisabled);
2866    }
2867
2868    const float oldX = x;
2869    const float oldY = y;
2870
2871    const mat4& transform = currentTransform();
2872    const bool pureTranslate = transform.isPureTranslate();
2873
2874    if (CC_LIKELY(pureTranslate)) {
2875        x = (int) floorf(x + transform.getTranslateX() + 0.5f);
2876        y = (int) floorf(y + transform.getTranslateY() + 0.5f);
2877    }
2878
2879    int alpha;
2880    SkXfermode::Mode mode;
2881    getAlphaAndMode(paint, &alpha, &mode);
2882
2883    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2884
2885    if (CC_UNLIKELY(mDrawModifiers.mHasShadow)) {
2886        fontRenderer.setFont(paint, mat4::identity());
2887        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2888                alpha, mode, oldX, oldY);
2889    }
2890
2891    const bool hasActiveLayer = hasLayer();
2892
2893    // We only pass a partial transform to the font renderer. That partial
2894    // matrix defines how glyphs are rasterized. Typically we want glyphs
2895    // to be rasterized at their final size on screen, which means the partial
2896    // matrix needs to take the scale factor into account.
2897    // When a partial matrix is used to transform glyphs during rasterization,
2898    // the mesh is generated with the inverse transform (in the case of scale,
2899    // the mesh is generated at 1.0 / scale for instance.) This allows us to
2900    // apply the full transform matrix at draw time in the vertex shader.
2901    // Applying the full matrix in the shader is the easiest way to handle
2902    // rotation and perspective and allows us to always generated quads in the
2903    // font renderer which greatly simplifies the code, clipping in particular.
2904    mat4 fontTransform = findBestFontTransform(transform);
2905    fontRenderer.setFont(paint, fontTransform);
2906
2907    // Pick the appropriate texture filtering
2908    bool linearFilter = !pureTranslate || fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2909    fontRenderer.setTextureFiltering(linearFilter);
2910
2911    // TODO: Implement better clipping for scaled/rotated text
2912    const Rect* clip = !pureTranslate ? NULL : mSnapshot->clipRect;
2913    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2914
2915    bool status;
2916    TextSetupFunctor functor(*this, x, y, pureTranslate, alpha, mode, paint);
2917
2918    // don't call issuedrawcommand, do it at end of batch
2919    bool forceFinish = (drawOpMode != kDrawOpMode_Defer);
2920    if (CC_UNLIKELY(paint->getTextAlign() != SkPaint::kLeft_Align)) {
2921        SkPaint paintCopy(*paint);
2922        paintCopy.setTextAlign(SkPaint::kLeft_Align);
2923        status = fontRenderer.renderPosText(&paintCopy, clip, text, 0, bytesCount, count, x, y,
2924                positions, hasActiveLayer ? &bounds : NULL, &functor, forceFinish);
2925    } else {
2926        status = fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2927                positions, hasActiveLayer ? &bounds : NULL, &functor, forceFinish);
2928    }
2929
2930    if ((status || drawOpMode != kDrawOpMode_Immediate) && hasActiveLayer) {
2931        if (!pureTranslate) {
2932            transform.mapRect(bounds);
2933        }
2934        dirtyLayerUnchecked(bounds, getRegion());
2935    }
2936
2937    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
2938
2939    return DrawGlInfo::kStatusDrew;
2940}
2941
2942status_t OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count, SkPath* path,
2943        float hOffset, float vOffset, SkPaint* paint) {
2944    if (text == NULL || count == 0 || mSnapshot->isIgnored() || canSkipText(paint)) {
2945        return DrawGlInfo::kStatusDone;
2946    }
2947
2948    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2949    fontRenderer.setFont(paint, mat4::identity());
2950    fontRenderer.setTextureFiltering(true);
2951
2952    int alpha;
2953    SkXfermode::Mode mode;
2954    getAlphaAndMode(paint, &alpha, &mode);
2955
2956    setupDraw();
2957    setupDrawTextGamma(paint);
2958    setupDrawDirtyRegionsDisabled();
2959    setupDrawWithTexture(true);
2960    setupDrawAlpha8Color(paint->getColor(), alpha);
2961    setupDrawColorFilter();
2962    setupDrawShader();
2963    setupDrawBlending(true, mode);
2964    setupDrawProgram();
2965    setupDrawModelView(0.0f, 0.0f, 0.0f, 0.0f, false, true);
2966    // Calling setupDrawTexture with the name 0 will enable the
2967    // uv attributes and increase the texture unit count
2968    // texture binding will be performed by the font renderer as
2969    // needed
2970    setupDrawTexture(0);
2971    setupDrawPureColorUniforms();
2972    setupDrawColorFilterUniforms();
2973    setupDrawShaderUniforms(false);
2974    setupDrawTextGammaUniforms();
2975
2976    const Rect* clip = &mSnapshot->getLocalClip();
2977    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2978
2979    const bool hasActiveLayer = hasLayer();
2980
2981    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2982            hOffset, vOffset, hasActiveLayer ? &bounds : NULL)) {
2983        if (hasActiveLayer) {
2984            currentTransform().mapRect(bounds);
2985            dirtyLayerUnchecked(bounds, getRegion());
2986        }
2987    }
2988
2989    return DrawGlInfo::kStatusDrew;
2990}
2991
2992status_t OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
2993    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2994
2995    mCaches.activeTexture(0);
2996
2997    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2998    if (!texture) return DrawGlInfo::kStatusDone;
2999    const AutoTexture autoCleanup(texture);
3000
3001    const float x = texture->left - texture->offset;
3002    const float y = texture->top - texture->offset;
3003
3004    drawPathTexture(texture, x, y, paint);
3005
3006    return DrawGlInfo::kStatusDrew;
3007}
3008
3009status_t OpenGLRenderer::drawLayer(Layer* layer, float x, float y) {
3010    if (!layer) {
3011        return DrawGlInfo::kStatusDone;
3012    }
3013
3014    mat4* transform = NULL;
3015    if (layer->isTextureLayer()) {
3016        transform = &layer->getTransform();
3017        if (!transform->isIdentity()) {
3018            save(0);
3019            currentTransform().multiply(*transform);
3020        }
3021    }
3022
3023    Rect transformed;
3024    Rect clip;
3025    const bool rejected = quickRejectNoScissor(x, y,
3026            x + layer->layer.getWidth(), y + layer->layer.getHeight(), transformed, clip);
3027
3028    if (rejected) {
3029        if (transform && !transform->isIdentity()) {
3030            restore();
3031        }
3032        return DrawGlInfo::kStatusDone;
3033    }
3034
3035    updateLayer(layer, true);
3036
3037    mCaches.setScissorEnabled(mScissorOptimizationDisabled || !clip.contains(transformed));
3038    mCaches.activeTexture(0);
3039
3040    if (CC_LIKELY(!layer->region.isEmpty())) {
3041        SkiaColorFilter* oldFilter = mDrawModifiers.mColorFilter;
3042        mDrawModifiers.mColorFilter = layer->getColorFilter();
3043
3044        if (layer->region.isRect()) {
3045            composeLayerRect(layer, layer->regionRect);
3046        } else if (layer->mesh) {
3047            const float a = getLayerAlpha(layer);
3048            setupDraw();
3049            setupDrawWithTexture();
3050            setupDrawColor(a, a, a, a);
3051            setupDrawColorFilter();
3052            setupDrawBlending(layer->isBlend() || a < 1.0f, layer->getMode(), false);
3053            setupDrawProgram();
3054            setupDrawPureColorUniforms();
3055            setupDrawColorFilterUniforms();
3056            setupDrawTexture(layer->getTexture());
3057            if (CC_LIKELY(currentTransform().isPureTranslate())) {
3058                int tx = (int) floorf(x + currentTransform().getTranslateX() + 0.5f);
3059                int ty = (int) floorf(y + currentTransform().getTranslateY() + 0.5f);
3060
3061                layer->setFilter(GL_NEAREST);
3062                setupDrawModelViewTranslate(tx, ty,
3063                        tx + layer->layer.getWidth(), ty + layer->layer.getHeight(), true);
3064            } else {
3065                layer->setFilter(GL_LINEAR);
3066                setupDrawModelViewTranslate(x, y,
3067                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
3068            }
3069            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
3070
3071            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
3072                    GL_UNSIGNED_SHORT, layer->meshIndices);
3073
3074            finishDrawTexture();
3075
3076#if DEBUG_LAYERS_AS_REGIONS
3077            drawRegionRects(layer->region);
3078#endif
3079        }
3080
3081        mDrawModifiers.mColorFilter = oldFilter;
3082
3083        if (layer->debugDrawUpdate) {
3084            layer->debugDrawUpdate = false;
3085            drawColorRect(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight(),
3086                    0x7f00ff00, SkXfermode::kSrcOver_Mode);
3087        }
3088    }
3089
3090    if (transform && !transform->isIdentity()) {
3091        restore();
3092    }
3093
3094    return DrawGlInfo::kStatusDrew;
3095}
3096
3097///////////////////////////////////////////////////////////////////////////////
3098// Shaders
3099///////////////////////////////////////////////////////////////////////////////
3100
3101void OpenGLRenderer::resetShader() {
3102    mDrawModifiers.mShader = NULL;
3103}
3104
3105void OpenGLRenderer::setupShader(SkiaShader* shader) {
3106    mDrawModifiers.mShader = shader;
3107    if (mDrawModifiers.mShader) {
3108        mDrawModifiers.mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
3109    }
3110}
3111
3112///////////////////////////////////////////////////////////////////////////////
3113// Color filters
3114///////////////////////////////////////////////////////////////////////////////
3115
3116void OpenGLRenderer::resetColorFilter() {
3117    mDrawModifiers.mColorFilter = NULL;
3118}
3119
3120void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
3121    mDrawModifiers.mColorFilter = filter;
3122}
3123
3124///////////////////////////////////////////////////////////////////////////////
3125// Drop shadow
3126///////////////////////////////////////////////////////////////////////////////
3127
3128void OpenGLRenderer::resetShadow() {
3129    mDrawModifiers.mHasShadow = false;
3130}
3131
3132void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
3133    mDrawModifiers.mHasShadow = true;
3134    mDrawModifiers.mShadowRadius = radius;
3135    mDrawModifiers.mShadowDx = dx;
3136    mDrawModifiers.mShadowDy = dy;
3137    mDrawModifiers.mShadowColor = color;
3138}
3139
3140///////////////////////////////////////////////////////////////////////////////
3141// Draw filters
3142///////////////////////////////////////////////////////////////////////////////
3143
3144void OpenGLRenderer::resetPaintFilter() {
3145    // when clearing the PaintFilter, the masks should also be cleared for simple DrawModifier
3146    // comparison, see MergingDrawBatch::canMergeWith
3147    mDrawModifiers.mHasDrawFilter = false;
3148    mDrawModifiers.mPaintFilterClearBits = 0;
3149    mDrawModifiers.mPaintFilterSetBits = 0;
3150}
3151
3152void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
3153    mDrawModifiers.mHasDrawFilter = true;
3154    mDrawModifiers.mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
3155    mDrawModifiers.mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
3156}
3157
3158SkPaint* OpenGLRenderer::filterPaint(SkPaint* paint) {
3159    if (CC_LIKELY(!mDrawModifiers.mHasDrawFilter || !paint)) {
3160        return paint;
3161    }
3162
3163    uint32_t flags = paint->getFlags();
3164
3165    mFilteredPaint = *paint;
3166    mFilteredPaint.setFlags((flags & ~mDrawModifiers.mPaintFilterClearBits) |
3167            mDrawModifiers.mPaintFilterSetBits);
3168
3169    return &mFilteredPaint;
3170}
3171
3172///////////////////////////////////////////////////////////////////////////////
3173// Drawing implementation
3174///////////////////////////////////////////////////////////////////////////////
3175
3176void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
3177        float x, float y, SkPaint* paint) {
3178    if (quickReject(x, y, x + texture->width, y + texture->height)) {
3179        return;
3180    }
3181
3182    int alpha;
3183    SkXfermode::Mode mode;
3184    getAlphaAndMode(paint, &alpha, &mode);
3185
3186    setupDraw();
3187    setupDrawWithTexture(true);
3188    setupDrawAlpha8Color(paint->getColor(), alpha);
3189    setupDrawColorFilter();
3190    setupDrawShader();
3191    setupDrawBlending(true, mode);
3192    setupDrawProgram();
3193    setupDrawModelView(x, y, x + texture->width, y + texture->height);
3194    setupDrawTexture(texture->id);
3195    setupDrawPureColorUniforms();
3196    setupDrawColorFilterUniforms();
3197    setupDrawShaderUniforms();
3198    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
3199
3200    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3201
3202    finishDrawTexture();
3203}
3204
3205// Same values used by Skia
3206#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
3207#define kStdUnderline_Offset    (1.0f / 9.0f)
3208#define kStdUnderline_Thickness (1.0f / 18.0f)
3209
3210void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
3211        float x, float y, SkPaint* paint) {
3212    // Handle underline and strike-through
3213    uint32_t flags = paint->getFlags();
3214    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
3215        SkPaint paintCopy(*paint);
3216        float underlineWidth = length;
3217        // If length is > 0.0f, we already measured the text for the text alignment
3218        if (length <= 0.0f) {
3219            underlineWidth = paintCopy.measureText(text, bytesCount);
3220        }
3221
3222        if (CC_LIKELY(underlineWidth > 0.0f)) {
3223            const float textSize = paintCopy.getTextSize();
3224            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
3225
3226            const float left = x;
3227            float top = 0.0f;
3228
3229            int linesCount = 0;
3230            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
3231            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
3232
3233            const int pointsCount = 4 * linesCount;
3234            float points[pointsCount];
3235            int currentPoint = 0;
3236
3237            if (flags & SkPaint::kUnderlineText_Flag) {
3238                top = y + textSize * kStdUnderline_Offset;
3239                points[currentPoint++] = left;
3240                points[currentPoint++] = top;
3241                points[currentPoint++] = left + underlineWidth;
3242                points[currentPoint++] = top;
3243            }
3244
3245            if (flags & SkPaint::kStrikeThruText_Flag) {
3246                top = y + textSize * kStdStrikeThru_Offset;
3247                points[currentPoint++] = left;
3248                points[currentPoint++] = top;
3249                points[currentPoint++] = left + underlineWidth;
3250                points[currentPoint++] = top;
3251            }
3252
3253            paintCopy.setStrokeWidth(strokeWidth);
3254
3255            drawLines(&points[0], pointsCount, &paintCopy);
3256        }
3257    }
3258}
3259
3260status_t OpenGLRenderer::drawRects(const float* rects, int count, SkPaint* paint) {
3261    if (mSnapshot->isIgnored()) {
3262        return DrawGlInfo::kStatusDone;
3263    }
3264
3265    int color = paint->getColor();
3266    // If a shader is set, preserve only the alpha
3267    if (mDrawModifiers.mShader) {
3268        color |= 0x00ffffff;
3269    }
3270    SkXfermode::Mode mode = getXfermode(paint->getXfermode());
3271
3272    return drawColorRects(rects, count, color, mode);
3273}
3274
3275status_t OpenGLRenderer::drawColorRects(const float* rects, int count, int color,
3276        SkXfermode::Mode mode, bool ignoreTransform, bool dirty, bool clip) {
3277    if (count == 0) {
3278        return DrawGlInfo::kStatusDone;
3279    }
3280
3281    float left = FLT_MAX;
3282    float top = FLT_MAX;
3283    float right = FLT_MIN;
3284    float bottom = FLT_MIN;
3285
3286    int vertexCount = 0;
3287    Vertex mesh[count * 6];
3288    Vertex* vertex = mesh;
3289
3290    for (int index = 0; index < count; index += 4) {
3291        float l = rects[index + 0];
3292        float t = rects[index + 1];
3293        float r = rects[index + 2];
3294        float b = rects[index + 3];
3295
3296        Vertex::set(vertex++, l, b);
3297        Vertex::set(vertex++, l, t);
3298        Vertex::set(vertex++, r, t);
3299        Vertex::set(vertex++, l, b);
3300        Vertex::set(vertex++, r, t);
3301        Vertex::set(vertex++, r, b);
3302
3303        vertexCount += 6;
3304
3305        left = fminf(left, l);
3306        top = fminf(top, t);
3307        right = fmaxf(right, r);
3308        bottom = fmaxf(bottom, b);
3309    }
3310
3311    if (clip && quickReject(left, top, right, bottom)) {
3312        return DrawGlInfo::kStatusDone;
3313    }
3314
3315    setupDraw();
3316    setupDrawNoTexture();
3317    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
3318    setupDrawShader();
3319    setupDrawColorFilter();
3320    setupDrawBlending(mode);
3321    setupDrawProgram();
3322    setupDrawDirtyRegionsDisabled();
3323    setupDrawModelView(0.0f, 0.0f, 1.0f, 1.0f, ignoreTransform, true);
3324    setupDrawColorUniforms();
3325    setupDrawShaderUniforms();
3326    setupDrawColorFilterUniforms();
3327    setupDrawVertices((GLvoid*) &mesh[0].position[0]);
3328
3329    if (dirty && hasLayer()) {
3330        dirtyLayer(left, top, right, bottom, currentTransform());
3331    }
3332
3333    glDrawArrays(GL_TRIANGLES, 0, vertexCount);
3334
3335    return DrawGlInfo::kStatusDrew;
3336}
3337
3338void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
3339        int color, SkXfermode::Mode mode, bool ignoreTransform) {
3340    // If a shader is set, preserve only the alpha
3341    if (mDrawModifiers.mShader) {
3342        color |= 0x00ffffff;
3343    }
3344
3345    setupDraw();
3346    setupDrawNoTexture();
3347    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
3348    setupDrawShader();
3349    setupDrawColorFilter();
3350    setupDrawBlending(mode);
3351    setupDrawProgram();
3352    setupDrawModelView(left, top, right, bottom, ignoreTransform);
3353    setupDrawColorUniforms();
3354    setupDrawShaderUniforms(ignoreTransform);
3355    setupDrawColorFilterUniforms();
3356    setupDrawSimpleMesh();
3357
3358    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3359}
3360
3361void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
3362        Texture* texture, SkPaint* paint) {
3363    int alpha;
3364    SkXfermode::Mode mode;
3365    getAlphaAndMode(paint, &alpha, &mode);
3366
3367    texture->setWrap(GL_CLAMP_TO_EDGE, true);
3368
3369    if (CC_LIKELY(currentTransform().isPureTranslate())) {
3370        const float x = (int) floorf(left + currentTransform().getTranslateX() + 0.5f);
3371        const float y = (int) floorf(top + currentTransform().getTranslateY() + 0.5f);
3372
3373        texture->setFilter(GL_NEAREST, true);
3374        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
3375                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
3376                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
3377    } else {
3378        texture->setFilter(FILTER(paint), true);
3379        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
3380                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
3381                GL_TRIANGLE_STRIP, gMeshCount);
3382    }
3383}
3384
3385void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
3386        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
3387    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
3388            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
3389}
3390
3391void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
3392        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
3393        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3394        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
3395
3396    setupDraw();
3397    setupDrawWithTexture();
3398    setupDrawColor(alpha, alpha, alpha, alpha);
3399    setupDrawColorFilter();
3400    setupDrawBlending(blend, mode, swapSrcDst);
3401    setupDrawProgram();
3402    if (!dirty) setupDrawDirtyRegionsDisabled();
3403    if (!ignoreScale) {
3404        setupDrawModelView(left, top, right, bottom, ignoreTransform);
3405    } else {
3406        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
3407    }
3408    setupDrawTexture(texture);
3409    setupDrawPureColorUniforms();
3410    setupDrawColorFilterUniforms();
3411    setupDrawMesh(vertices, texCoords, vbo);
3412
3413    glDrawArrays(drawMode, 0, elementsCount);
3414
3415    finishDrawTexture();
3416}
3417
3418void OpenGLRenderer::drawAlpha8TextureMesh(float left, float top, float right, float bottom,
3419        GLuint texture, bool hasColor, int color, int alpha, SkXfermode::Mode mode,
3420        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3421        bool ignoreTransform, bool ignoreScale, bool dirty) {
3422
3423    setupDraw();
3424    setupDrawWithTexture(true);
3425    if (hasColor) {
3426        setupDrawAlpha8Color(color, alpha);
3427    }
3428    setupDrawColorFilter();
3429    setupDrawShader();
3430    setupDrawBlending(true, mode);
3431    setupDrawProgram();
3432    if (!dirty) setupDrawDirtyRegionsDisabled();
3433    if (!ignoreScale) {
3434        setupDrawModelView(left, top, right, bottom, ignoreTransform);
3435    } else {
3436        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
3437    }
3438    setupDrawTexture(texture);
3439    setupDrawPureColorUniforms();
3440    setupDrawColorFilterUniforms();
3441    setupDrawShaderUniforms();
3442    setupDrawMesh(vertices, texCoords);
3443
3444    glDrawArrays(drawMode, 0, elementsCount);
3445
3446    finishDrawTexture();
3447}
3448
3449void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
3450        ProgramDescription& description, bool swapSrcDst) {
3451    blend = blend || mode != SkXfermode::kSrcOver_Mode;
3452
3453    if (blend) {
3454        // These blend modes are not supported by OpenGL directly and have
3455        // to be implemented using shaders. Since the shader will perform
3456        // the blending, turn blending off here
3457        // If the blend mode cannot be implemented using shaders, fall
3458        // back to the default SrcOver blend mode instead
3459        if (CC_UNLIKELY(mode > SkXfermode::kScreen_Mode)) {
3460            if (CC_UNLIKELY(mExtensions.hasFramebufferFetch())) {
3461                description.framebufferMode = mode;
3462                description.swapSrcDst = swapSrcDst;
3463
3464                if (mCaches.blend) {
3465                    glDisable(GL_BLEND);
3466                    mCaches.blend = false;
3467                }
3468
3469                return;
3470            } else {
3471                mode = SkXfermode::kSrcOver_Mode;
3472            }
3473        }
3474
3475        if (!mCaches.blend) {
3476            glEnable(GL_BLEND);
3477        }
3478
3479        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
3480        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
3481
3482        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
3483            glBlendFunc(sourceMode, destMode);
3484            mCaches.lastSrcMode = sourceMode;
3485            mCaches.lastDstMode = destMode;
3486        }
3487    } else if (mCaches.blend) {
3488        glDisable(GL_BLEND);
3489    }
3490    mCaches.blend = blend;
3491}
3492
3493bool OpenGLRenderer::useProgram(Program* program) {
3494    if (!program->isInUse()) {
3495        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
3496        program->use();
3497        mCaches.currentProgram = program;
3498        return false;
3499    }
3500    return true;
3501}
3502
3503void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
3504    TextureVertex* v = &mMeshVertices[0];
3505    TextureVertex::setUV(v++, u1, v1);
3506    TextureVertex::setUV(v++, u2, v1);
3507    TextureVertex::setUV(v++, u1, v2);
3508    TextureVertex::setUV(v++, u2, v2);
3509}
3510
3511void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) const {
3512    getAlphaAndModeDirect(paint, alpha,  mode);
3513    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3514        // if drawing a layer, ignore the paint's alpha
3515        *alpha = mDrawModifiers.mOverrideLayerAlpha;
3516    }
3517    *alpha *= mSnapshot->alpha;
3518}
3519
3520float OpenGLRenderer::getLayerAlpha(Layer* layer) const {
3521    float alpha;
3522    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3523        alpha = mDrawModifiers.mOverrideLayerAlpha;
3524    } else {
3525        alpha = layer->getAlpha() / 255.0f;
3526    }
3527    return alpha * mSnapshot->alpha;
3528}
3529
3530}; // namespace uirenderer
3531}; // namespace android
3532