OpenGLRenderer.cpp revision ddc52285ca6fd147f442a21e90e0e4702a10d304 
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 <SkTypeface.h>
25
26#include <utils/Log.h>
27#include <utils/StopWatch.h>
28
29#include <private/hwui/DrawGlInfo.h>
30
31#include <ui/Rect.h>
32
33#include "OpenGLRenderer.h"
34#include "DeferredDisplayList.h"
35#include "DisplayListRenderer.h"
36#include "Fence.h"
37#include "PathTessellator.h"
38#include "Properties.h"
39#include "ShadowTessellator.h"
40#include "utils/GLUtils.h"
41#include "Vector.h"
42#include "VertexBuffer.h"
43
44namespace android {
45namespace uirenderer {
46
47///////////////////////////////////////////////////////////////////////////////
48// Defines
49///////////////////////////////////////////////////////////////////////////////
50
51#define RAD_TO_DEG (180.0f / 3.14159265f)
52#define MIN_ANGLE 0.001f
53
54#define ALPHA_THRESHOLD 0
55
56static GLenum getFilter(const SkPaint* paint) {
57    if (!paint || paint->getFilterLevel() != SkPaint::kNone_FilterLevel) {
58        return GL_LINEAR;
59    }
60    return GL_NEAREST;
61}
62
63///////////////////////////////////////////////////////////////////////////////
64// Globals
65///////////////////////////////////////////////////////////////////////////////
66
67/**
68 * Structure mapping Skia xfermodes to OpenGL blending factors.
69 */
70struct Blender {
71    SkXfermode::Mode mode;
72    GLenum src;
73    GLenum dst;
74}; // struct Blender
75
76// In this array, the index of each Blender equals the value of the first
77// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
78static const Blender gBlends[] = {
79    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
80    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
81    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
82    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
83    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
84    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
85    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
86    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
87    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
88    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
89    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
90    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
91    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
92    { SkXfermode::kModulate_Mode, GL_ZERO,                GL_SRC_COLOR },
93    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
94};
95
96// This array contains the swapped version of each SkXfermode. For instance
97// this array's SrcOver blending mode is actually DstOver. You can refer to
98// createLayer() for more information on the purpose of this array.
99static const Blender gBlendsSwap[] = {
100    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
101    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
102    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
103    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
104    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
105    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
106    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
107    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
108    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
109    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
110    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
111    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
112    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
113    { SkXfermode::kModulate_Mode, GL_DST_COLOR,           GL_ZERO },
114    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
115};
116
117///////////////////////////////////////////////////////////////////////////////
118// Functions
119///////////////////////////////////////////////////////////////////////////////
120
121template<typename T>
122static inline T min(T a, T b) {
123    return a < b ? a : b;
124}
125
126///////////////////////////////////////////////////////////////////////////////
127// Constructors/destructor
128///////////////////////////////////////////////////////////////////////////////
129
130OpenGLRenderer::OpenGLRenderer():
131        mCaches(Caches::getInstance()), mExtensions(Extensions::getInstance()) {
132    // *set* draw modifiers to be 0
133    memset(&mDrawModifiers, 0, sizeof(mDrawModifiers));
134    mDrawModifiers.mOverrideLayerAlpha = 1.0f;
135
136    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
137
138    mFrameStarted = false;
139    mCountOverdraw = false;
140
141    mScissorOptimizationDisabled = false;
142}
143
144OpenGLRenderer::~OpenGLRenderer() {
145    // The context has already been destroyed at this point, do not call
146    // GL APIs. All GL state should be kept in Caches.h
147}
148
149void OpenGLRenderer::initProperties() {
150    char property[PROPERTY_VALUE_MAX];
151    if (property_get(PROPERTY_DISABLE_SCISSOR_OPTIMIZATION, property, "false")) {
152        mScissorOptimizationDisabled = !strcasecmp(property, "true");
153        INIT_LOGD("  Scissor optimization %s",
154                mScissorOptimizationDisabled ? "disabled" : "enabled");
155    } else {
156        INIT_LOGD("  Scissor optimization enabled");
157    }
158}
159
160///////////////////////////////////////////////////////////////////////////////
161// Setup
162///////////////////////////////////////////////////////////////////////////////
163
164void OpenGLRenderer::setViewport(int width, int height) {
165    initViewport(width, height);
166
167    glDisable(GL_DITHER);
168    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
169
170    glEnableVertexAttribArray(Program::kBindingPosition);
171}
172
173void OpenGLRenderer::initViewport(int width, int height) {
174    mProjectionMatrix.loadOrtho(0, width, height, 0, -1, 1);
175
176    initializeViewport(width, height);
177}
178
179void OpenGLRenderer::setupFrameState(float left, float top,
180        float right, float bottom, bool opaque) {
181    mCaches.clearGarbage();
182
183    initializeSaveStack(left, top, right, bottom);
184    mOpaque = opaque;
185    mTilingClip.set(left, top, right, bottom);
186}
187
188status_t OpenGLRenderer::startFrame() {
189    if (mFrameStarted) return DrawGlInfo::kStatusDone;
190    mFrameStarted = true;
191
192    mDirtyClip = true;
193
194    discardFramebuffer(mTilingClip.left, mTilingClip.top, mTilingClip.right, mTilingClip.bottom);
195
196    glViewport(0, 0, getWidth(), getHeight());
197
198    // Functors break the tiling extension in pretty spectacular ways
199    // This ensures we don't use tiling when a functor is going to be
200    // invoked during the frame
201    mSuppressTiling = mCaches.hasRegisteredFunctors();
202
203    startTilingCurrentClip(true);
204
205    debugOverdraw(true, true);
206
207    return clear(mTilingClip.left, mTilingClip.top,
208            mTilingClip.right, mTilingClip.bottom, mOpaque);
209}
210
211status_t OpenGLRenderer::prepareDirty(float left, float top,
212        float right, float bottom, bool opaque) {
213
214    setupFrameState(left, top, right, bottom, opaque);
215
216    // Layer renderers will start the frame immediately
217    // The framebuffer renderer will first defer the display list
218    // for each layer and wait until the first drawing command
219    // to start the frame
220    if (currentSnapshot()->fbo == 0) {
221        syncState();
222        updateLayers();
223    } else {
224        return startFrame();
225    }
226
227    return DrawGlInfo::kStatusDone;
228}
229
230void OpenGLRenderer::discardFramebuffer(float left, float top, float right, float bottom) {
231    // If we know that we are going to redraw the entire framebuffer,
232    // perform a discard to let the driver know we don't need to preserve
233    // the back buffer for this frame.
234    if (mExtensions.hasDiscardFramebuffer() &&
235            left <= 0.0f && top <= 0.0f && right >= getWidth() && bottom >= getHeight()) {
236        const bool isFbo = getTargetFbo() == 0;
237        const GLenum attachments[] = {
238                isFbo ? (const GLenum) GL_COLOR_EXT : (const GLenum) GL_COLOR_ATTACHMENT0,
239                isFbo ? (const GLenum) GL_STENCIL_EXT : (const GLenum) GL_STENCIL_ATTACHMENT };
240        glDiscardFramebufferEXT(GL_FRAMEBUFFER, 1, attachments);
241    }
242}
243
244status_t OpenGLRenderer::clear(float left, float top, float right, float bottom, bool opaque) {
245    if (!opaque || mCountOverdraw) {
246        mCaches.enableScissor();
247        mCaches.setScissor(left, currentSnapshot()->height - bottom, right - left, bottom - top);
248        glClear(GL_COLOR_BUFFER_BIT);
249        return DrawGlInfo::kStatusDrew;
250    }
251
252    mCaches.resetScissor();
253    return DrawGlInfo::kStatusDone;
254}
255
256void OpenGLRenderer::syncState() {
257    if (mCaches.blend) {
258        glEnable(GL_BLEND);
259    } else {
260        glDisable(GL_BLEND);
261    }
262}
263
264void OpenGLRenderer::startTilingCurrentClip(bool opaque) {
265    if (!mSuppressTiling) {
266        const Snapshot* snapshot = currentSnapshot();
267
268        const Rect* clip = &mTilingClip;
269        if (snapshot->flags & Snapshot::kFlagFboTarget) {
270            clip = &(snapshot->layer->clipRect);
271        }
272
273        startTiling(*clip, snapshot->height, opaque);
274    }
275}
276
277void OpenGLRenderer::startTiling(const Rect& clip, int windowHeight, bool opaque) {
278    if (!mSuppressTiling) {
279        mCaches.startTiling(clip.left, windowHeight - clip.bottom,
280                clip.right - clip.left, clip.bottom - clip.top, opaque);
281    }
282}
283
284void OpenGLRenderer::endTiling() {
285    if (!mSuppressTiling) mCaches.endTiling();
286}
287
288void OpenGLRenderer::finish() {
289    renderOverdraw();
290    endTiling();
291
292    // When finish() is invoked on FBO 0 we've reached the end
293    // of the current frame
294    if (getTargetFbo() == 0) {
295        mCaches.pathCache.trim();
296    }
297
298    if (!suppressErrorChecks()) {
299#if DEBUG_OPENGL
300        GLUtils::dumpGLErrors();
301#endif
302
303#if DEBUG_MEMORY_USAGE
304        mCaches.dumpMemoryUsage();
305#else
306        if (mCaches.getDebugLevel() & kDebugMemory) {
307            mCaches.dumpMemoryUsage();
308        }
309#endif
310    }
311
312    if (mCountOverdraw) {
313        countOverdraw();
314    }
315
316    mFrameStarted = false;
317}
318
319void OpenGLRenderer::interrupt() {
320    if (mCaches.currentProgram) {
321        if (mCaches.currentProgram->isInUse()) {
322            mCaches.currentProgram->remove();
323            mCaches.currentProgram = NULL;
324        }
325    }
326    mCaches.resetActiveTexture();
327    mCaches.unbindMeshBuffer();
328    mCaches.unbindIndicesBuffer();
329    mCaches.resetVertexPointers();
330    mCaches.disableTexCoordsVertexArray();
331    debugOverdraw(false, false);
332}
333
334void OpenGLRenderer::resume() {
335    const Snapshot* snapshot = currentSnapshot();
336    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
337    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
338    debugOverdraw(true, false);
339
340    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
341
342    mCaches.scissorEnabled = glIsEnabled(GL_SCISSOR_TEST);
343    mCaches.enableScissor();
344    mCaches.resetScissor();
345    dirtyClip();
346
347    mCaches.activeTexture(0);
348    mCaches.resetBoundTextures();
349
350    mCaches.blend = true;
351    glEnable(GL_BLEND);
352    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
353    glBlendEquation(GL_FUNC_ADD);
354}
355
356void OpenGLRenderer::resumeAfterLayer() {
357    const Snapshot* snapshot = currentSnapshot();
358    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
359    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
360    debugOverdraw(true, false);
361
362    mCaches.resetScissor();
363    dirtyClip();
364}
365
366status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
367    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
368
369    Rect clip(*currentClipRect());
370    clip.snapToPixelBoundaries();
371
372    // Since we don't know what the functor will draw, let's dirty
373    // the entire clip region
374    if (hasLayer()) {
375        dirtyLayerUnchecked(clip, getRegion());
376    }
377
378    DrawGlInfo info;
379    info.clipLeft = clip.left;
380    info.clipTop = clip.top;
381    info.clipRight = clip.right;
382    info.clipBottom = clip.bottom;
383    info.isLayer = hasLayer();
384    info.width = currentSnapshot()->viewport.getWidth();
385    info.height = currentSnapshot()->height;
386    currentTransform()->copyTo(&info.transform[0]);
387
388    bool dirtyClip = mDirtyClip;
389    // setup GL state for functor
390    if (mDirtyClip) {
391        setStencilFromClip(); // can issue draws, so must precede enableScissor()/interrupt()
392    }
393    if (mCaches.enableScissor() || dirtyClip) {
394        setScissorFromClip();
395    }
396    interrupt();
397
398    // call functor immediately after GL state setup
399    (*functor)(DrawGlInfo::kModeDraw, &info);
400
401    resume();
402    return DrawGlInfo::kStatusDrew;
403}
404
405///////////////////////////////////////////////////////////////////////////////
406// Debug
407///////////////////////////////////////////////////////////////////////////////
408
409void OpenGLRenderer::eventMark(const char* name) const {
410    mCaches.eventMark(0, name);
411}
412
413void OpenGLRenderer::startMark(const char* name) const {
414    mCaches.startMark(0, name);
415}
416
417void OpenGLRenderer::endMark() const {
418    mCaches.endMark();
419}
420
421void OpenGLRenderer::debugOverdraw(bool enable, bool clear) {
422    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
423        if (clear) {
424            mCaches.disableScissor();
425            mCaches.stencil.clear();
426        }
427        if (enable) {
428            mCaches.stencil.enableDebugWrite();
429        } else {
430            mCaches.stencil.disable();
431        }
432    }
433}
434
435void OpenGLRenderer::renderOverdraw() {
436    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
437        const Rect* clip = &mTilingClip;
438
439        mCaches.enableScissor();
440        mCaches.setScissor(clip->left, firstSnapshot()->height - clip->bottom,
441                clip->right - clip->left, clip->bottom - clip->top);
442
443        // 1x overdraw
444        mCaches.stencil.enableDebugTest(2);
445        drawColor(mCaches.getOverdrawColor(1), SkXfermode::kSrcOver_Mode);
446
447        // 2x overdraw
448        mCaches.stencil.enableDebugTest(3);
449        drawColor(mCaches.getOverdrawColor(2), SkXfermode::kSrcOver_Mode);
450
451        // 3x overdraw
452        mCaches.stencil.enableDebugTest(4);
453        drawColor(mCaches.getOverdrawColor(3), SkXfermode::kSrcOver_Mode);
454
455        // 4x overdraw and higher
456        mCaches.stencil.enableDebugTest(4, true);
457        drawColor(mCaches.getOverdrawColor(4), SkXfermode::kSrcOver_Mode);
458
459        mCaches.stencil.disable();
460    }
461}
462
463void OpenGLRenderer::countOverdraw() {
464    size_t count = getWidth() * getHeight();
465    uint32_t* buffer = new uint32_t[count];
466    glReadPixels(0, 0, getWidth(), getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, &buffer[0]);
467
468    size_t total = 0;
469    for (size_t i = 0; i < count; i++) {
470        total += buffer[i] & 0xff;
471    }
472
473    mOverdraw = total / float(count);
474
475    delete[] buffer;
476}
477
478///////////////////////////////////////////////////////////////////////////////
479// Layers
480///////////////////////////////////////////////////////////////////////////////
481
482bool OpenGLRenderer::updateLayer(Layer* layer, bool inFrame) {
483    if (layer->deferredUpdateScheduled && layer->renderer &&
484            layer->displayList.get() && layer->displayList->isRenderable()) {
485        ATRACE_CALL();
486
487        Rect& dirty = layer->dirtyRect;
488
489        if (inFrame) {
490            endTiling();
491            debugOverdraw(false, false);
492        }
493
494        if (CC_UNLIKELY(inFrame || mCaches.drawDeferDisabled)) {
495            layer->render();
496        } else {
497            layer->defer();
498        }
499
500        if (inFrame) {
501            resumeAfterLayer();
502            startTilingCurrentClip();
503        }
504
505        layer->debugDrawUpdate = mCaches.debugLayersUpdates;
506        layer->hasDrawnSinceUpdate = false;
507
508        return true;
509    }
510
511    return false;
512}
513
514void OpenGLRenderer::updateLayers() {
515    // If draw deferring is enabled this method will simply defer
516    // the display list of each individual layer. The layers remain
517    // in the layer updates list which will be cleared by flushLayers().
518    int count = mLayerUpdates.size();
519    if (count > 0) {
520        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
521            startMark("Layer Updates");
522        } else {
523            startMark("Defer Layer Updates");
524        }
525
526        // Note: it is very important to update the layers in order
527        for (int i = 0; i < count; i++) {
528            Layer* layer = mLayerUpdates.itemAt(i);
529            updateLayer(layer, false);
530            if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
531                mCaches.resourceCache.decrementRefcount(layer);
532            }
533        }
534
535        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
536            mLayerUpdates.clear();
537            glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
538        }
539        endMark();
540    }
541}
542
543void OpenGLRenderer::flushLayers() {
544    int count = mLayerUpdates.size();
545    if (count > 0) {
546        startMark("Apply Layer Updates");
547        char layerName[12];
548
549        // Note: it is very important to update the layers in order
550        for (int i = 0; i < count; i++) {
551            sprintf(layerName, "Layer #%d", i);
552            startMark(layerName);
553
554            ATRACE_BEGIN("flushLayer");
555            Layer* layer = mLayerUpdates.itemAt(i);
556            layer->flush();
557            ATRACE_END();
558
559            mCaches.resourceCache.decrementRefcount(layer);
560
561            endMark();
562        }
563
564        mLayerUpdates.clear();
565        glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
566
567        endMark();
568    }
569}
570
571void OpenGLRenderer::pushLayerUpdate(Layer* layer) {
572    if (layer) {
573        // Make sure we don't introduce duplicates.
574        // SortedVector would do this automatically but we need to respect
575        // the insertion order. The linear search is not an issue since
576        // this list is usually very short (typically one item, at most a few)
577        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
578            if (mLayerUpdates.itemAt(i) == layer) {
579                return;
580            }
581        }
582        mLayerUpdates.push_back(layer);
583        mCaches.resourceCache.incrementRefcount(layer);
584    }
585}
586
587void OpenGLRenderer::cancelLayerUpdate(Layer* layer) {
588    if (layer) {
589        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
590            if (mLayerUpdates.itemAt(i) == layer) {
591                mLayerUpdates.removeAt(i);
592                mCaches.resourceCache.decrementRefcount(layer);
593                break;
594            }
595        }
596    }
597}
598
599void OpenGLRenderer::clearLayerUpdates() {
600    size_t count = mLayerUpdates.size();
601    if (count > 0) {
602        mCaches.resourceCache.lock();
603        for (size_t i = 0; i < count; i++) {
604            mCaches.resourceCache.decrementRefcountLocked(mLayerUpdates.itemAt(i));
605        }
606        mCaches.resourceCache.unlock();
607        mLayerUpdates.clear();
608    }
609}
610
611void OpenGLRenderer::flushLayerUpdates() {
612    syncState();
613    updateLayers();
614    flushLayers();
615    // Wait for all the layer updates to be executed
616    AutoFence fence;
617}
618
619///////////////////////////////////////////////////////////////////////////////
620// State management
621///////////////////////////////////////////////////////////////////////////////
622
623void OpenGLRenderer::onSnapshotRestored(const Snapshot& removed, const Snapshot& restored) {
624    bool restoreOrtho = removed.flags & Snapshot::kFlagDirtyOrtho;
625    bool restoreClip = removed.flags & Snapshot::kFlagClipSet;
626    bool restoreLayer = removed.flags & Snapshot::kFlagIsLayer;
627
628    if (restoreOrtho) {
629        const Rect& r = restored.viewport;
630        glViewport(r.left, r.top, r.right, r.bottom);
631        mProjectionMatrix.load(removed.orthoMatrix); // TODO: should ortho be stored in 'restored'?
632    }
633
634    if (restoreClip) {
635        dirtyClip();
636    }
637
638    if (restoreLayer) {
639        endMark(); // Savelayer
640        startMark("ComposeLayer");
641        composeLayer(removed, restored);
642        endMark();
643    }
644}
645
646///////////////////////////////////////////////////////////////////////////////
647// Layers
648///////////////////////////////////////////////////////////////////////////////
649
650int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
651        const SkPaint* paint, int flags, const SkPath* convexMask) {
652    const int count = saveSnapshot(flags);
653
654    if (!currentSnapshot()->isIgnored()) {
655        createLayer(left, top, right, bottom, paint, flags, convexMask);
656    }
657
658    return count;
659}
660
661void OpenGLRenderer::calculateLayerBoundsAndClip(Rect& bounds, Rect& clip, bool fboLayer) {
662    const Rect untransformedBounds(bounds);
663
664    currentTransform()->mapRect(bounds);
665
666    // Layers only make sense if they are in the framebuffer's bounds
667    if (bounds.intersect(*currentClipRect())) {
668        // We cannot work with sub-pixels in this case
669        bounds.snapToPixelBoundaries();
670
671        // When the layer is not an FBO, we may use glCopyTexImage so we
672        // need to make sure the layer does not extend outside the bounds
673        // of the framebuffer
674        if (!bounds.intersect(currentSnapshot()->previous->viewport)) {
675            bounds.setEmpty();
676        } else if (fboLayer) {
677            clip.set(bounds);
678            mat4 inverse;
679            inverse.loadInverse(*currentTransform());
680            inverse.mapRect(clip);
681            clip.snapToPixelBoundaries();
682            if (clip.intersect(untransformedBounds)) {
683                clip.translate(-untransformedBounds.left, -untransformedBounds.top);
684                bounds.set(untransformedBounds);
685            } else {
686                clip.setEmpty();
687            }
688        }
689    } else {
690        bounds.setEmpty();
691    }
692}
693
694void OpenGLRenderer::updateSnapshotIgnoreForLayer(const Rect& bounds, const Rect& clip,
695        bool fboLayer, int alpha) {
696    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
697            bounds.getHeight() > mCaches.maxTextureSize ||
698            (fboLayer && clip.isEmpty())) {
699        mSnapshot->empty = fboLayer;
700    } else {
701        mSnapshot->invisible = mSnapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
702    }
703}
704
705int OpenGLRenderer::saveLayerDeferred(float left, float top, float right, float bottom,
706        const SkPaint* paint, int flags) {
707    const int count = saveSnapshot(flags);
708
709    if (!currentSnapshot()->isIgnored() && (flags & SkCanvas::kClipToLayer_SaveFlag)) {
710        // initialize the snapshot as though it almost represents an FBO layer so deferred draw
711        // operations will be able to store and restore the current clip and transform info, and
712        // quick rejection will be correct (for display lists)
713
714        Rect bounds(left, top, right, bottom);
715        Rect clip;
716        calculateLayerBoundsAndClip(bounds, clip, true);
717        updateSnapshotIgnoreForLayer(bounds, clip, true, getAlphaDirect(paint));
718
719        if (!currentSnapshot()->isIgnored()) {
720            mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
721            mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
722            mSnapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
723        }
724    }
725
726    return count;
727}
728
729/**
730 * Layers are viewed by Skia are slightly different than layers in image editing
731 * programs (for instance.) When a layer is created, previously created layers
732 * and the frame buffer still receive every drawing command. For instance, if a
733 * layer is created and a shape intersecting the bounds of the layers and the
734 * framebuffer is draw, the shape will be drawn on both (unless the layer was
735 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
736 *
737 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
738 * texture. Unfortunately, this is inefficient as it requires every primitive to
739 * be drawn n + 1 times, where n is the number of active layers. In practice this
740 * means, for every primitive:
741 *   - Switch active frame buffer
742 *   - Change viewport, clip and projection matrix
743 *   - Issue the drawing
744 *
745 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
746 * To avoid this, layers are implemented in a different way here, at least in the
747 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
748 * is set. When this flag is set we can redirect all drawing operations into a
749 * single FBO.
750 *
751 * This implementation relies on the frame buffer being at least RGBA 8888. When
752 * a layer is created, only a texture is created, not an FBO. The content of the
753 * frame buffer contained within the layer's bounds is copied into this texture
754 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
755 * buffer and drawing continues as normal. This technique therefore treats the
756 * frame buffer as a scratch buffer for the layers.
757 *
758 * To compose the layers back onto the frame buffer, each layer texture
759 * (containing the original frame buffer data) is drawn as a simple quad over
760 * the frame buffer. The trick is that the quad is set as the composition
761 * destination in the blending equation, and the frame buffer becomes the source
762 * of the composition.
763 *
764 * Drawing layers with an alpha value requires an extra step before composition.
765 * An empty quad is drawn over the layer's region in the frame buffer. This quad
766 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
767 * quad is used to multiply the colors in the frame buffer. This is achieved by
768 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
769 * GL_ZERO, GL_SRC_ALPHA.
770 *
771 * Because glCopyTexImage2D() can be slow, an alternative implementation might
772 * be use to draw a single clipped layer. The implementation described above
773 * is correct in every case.
774 *
775 * (1) The frame buffer is actually not cleared right away. To allow the GPU
776 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
777 *     buffer is left untouched until the first drawing operation. Only when
778 *     something actually gets drawn are the layers regions cleared.
779 */
780bool OpenGLRenderer::createLayer(float left, float top, float right, float bottom,
781        const SkPaint* paint, int flags, const SkPath* convexMask) {
782    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
783    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
784
785    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
786
787    // Window coordinates of the layer
788    Rect clip;
789    Rect bounds(left, top, right, bottom);
790    calculateLayerBoundsAndClip(bounds, clip, fboLayer);
791    updateSnapshotIgnoreForLayer(bounds, clip, fboLayer, getAlphaDirect(paint));
792
793    // Bail out if we won't draw in this snapshot
794    if (currentSnapshot()->isIgnored()) {
795        return false;
796    }
797
798    mCaches.activeTexture(0);
799    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
800    if (!layer) {
801        return false;
802    }
803
804    layer->setPaint(paint);
805    layer->layer.set(bounds);
806    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
807            bounds.getWidth() / float(layer->getWidth()), 0.0f);
808
809    layer->setBlend(true);
810    layer->setDirty(false);
811    layer->setConvexMask(convexMask); // note: the mask must be cleared before returning to the cache
812
813    // Save the layer in the snapshot
814    mSnapshot->flags |= Snapshot::kFlagIsLayer;
815    mSnapshot->layer = layer;
816
817    startMark("SaveLayer");
818    if (fboLayer) {
819        return createFboLayer(layer, bounds, clip);
820    } else {
821        // Copy the framebuffer into the layer
822        layer->bindTexture();
823        if (!bounds.isEmpty()) {
824            if (layer->isEmpty()) {
825                // Workaround for some GL drivers. When reading pixels lying outside
826                // of the window we should get undefined values for those pixels.
827                // Unfortunately some drivers will turn the entire target texture black
828                // when reading outside of the window.
829                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->getWidth(), layer->getHeight(),
830                        0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
831                layer->setEmpty(false);
832            }
833
834            glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
835                    mSnapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
836
837            // Enqueue the buffer coordinates to clear the corresponding region later
838            mLayers.push(new Rect(bounds));
839        }
840    }
841
842    return true;
843}
844
845bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, Rect& clip) {
846    layer->clipRect.set(clip);
847    layer->setFbo(mCaches.fboCache.get());
848
849    mSnapshot->region = &mSnapshot->layer->region;
850    mSnapshot->flags |= Snapshot::kFlagFboTarget | Snapshot::kFlagIsFboLayer |
851            Snapshot::kFlagDirtyOrtho;
852    mSnapshot->fbo = layer->getFbo();
853    mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
854    mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
855    mSnapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
856    mSnapshot->height = bounds.getHeight();
857    mSnapshot->orthoMatrix.load(mProjectionMatrix);
858
859    endTiling();
860    debugOverdraw(false, false);
861    // Bind texture to FBO
862    glBindFramebuffer(GL_FRAMEBUFFER, layer->getFbo());
863    layer->bindTexture();
864
865    // Initialize the texture if needed
866    if (layer->isEmpty()) {
867        layer->allocateTexture();
868        layer->setEmpty(false);
869    }
870
871    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
872            layer->getTexture(), 0);
873
874    startTilingCurrentClip(true);
875
876    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
877    mCaches.enableScissor();
878    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
879            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
880    glClear(GL_COLOR_BUFFER_BIT);
881
882    dirtyClip();
883
884    // Change the ortho projection
885    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
886
887    mProjectionMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
888
889    return true;
890}
891
892/**
893 * Read the documentation of createLayer() before doing anything in this method.
894 */
895void OpenGLRenderer::composeLayer(const Snapshot& removed, const Snapshot& restored) {
896    if (!removed.layer) {
897        ALOGE("Attempting to compose a layer that does not exist");
898        return;
899    }
900
901    Layer* layer = removed.layer;
902    const Rect& rect = layer->layer;
903    const bool fboLayer = removed.flags & Snapshot::kFlagIsFboLayer;
904
905    bool clipRequired = false;
906    calculateQuickRejectForScissor(rect.left, rect.top, rect.right, rect.bottom,
907            &clipRequired, false); // safely ignore return, should never be rejected
908    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
909
910    if (fboLayer) {
911        endTiling();
912
913        // Detach the texture from the FBO
914        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
915
916        layer->removeFbo(false);
917
918        // Unbind current FBO and restore previous one
919        glBindFramebuffer(GL_FRAMEBUFFER, restored.fbo);
920        debugOverdraw(true, false);
921
922        startTilingCurrentClip();
923    }
924
925    if (!fboLayer && layer->getAlpha() < 255) {
926        SkPaint layerPaint;
927        layerPaint.setAlpha(layer->getAlpha());
928        layerPaint.setXfermodeMode(SkXfermode::kDstIn_Mode);
929        layerPaint.setColorFilter(layer->getColorFilter());
930
931        drawColorRect(rect.left, rect.top, rect.right, rect.bottom, &layerPaint, true);
932        // Required below, composeLayerRect() will divide by 255
933        layer->setAlpha(255);
934    }
935
936    mCaches.unbindMeshBuffer();
937
938    mCaches.activeTexture(0);
939
940    // When the layer is stored in an FBO, we can save a bit of fillrate by
941    // drawing only the dirty region
942    if (fboLayer) {
943        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *restored.transform);
944        composeLayerRegion(layer, rect);
945    } else if (!rect.isEmpty()) {
946        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
947
948        save(0);
949        // the layer contains screen buffer content that shouldn't be alpha modulated
950        // (and any necessary alpha modulation was handled drawing into the layer)
951        mSnapshot->alpha = 1.0f;
952        composeLayerRect(layer, rect, true);
953        restore();
954    }
955
956    dirtyClip();
957
958    // Failing to add the layer to the cache should happen only if the layer is too large
959    layer->setConvexMask(NULL);
960    if (!mCaches.layerCache.put(layer)) {
961        LAYER_LOGD("Deleting layer");
962        Caches::getInstance().resourceCache.decrementRefcount(layer);
963    }
964}
965
966void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
967    float alpha = getLayerAlpha(layer);
968
969    setupDraw();
970    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
971        setupDrawWithTexture();
972    } else {
973        setupDrawWithExternalTexture();
974    }
975    setupDrawTextureTransform();
976    setupDrawColor(alpha, alpha, alpha, alpha);
977    setupDrawColorFilter(layer->getColorFilter());
978    setupDrawBlending(layer);
979    setupDrawProgram();
980    setupDrawPureColorUniforms();
981    setupDrawColorFilterUniforms(layer->getColorFilter());
982    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
983        setupDrawTexture(layer->getTexture());
984    } else {
985        setupDrawExternalTexture(layer->getTexture());
986    }
987    if (currentTransform()->isPureTranslate() &&
988            !layer->getForceFilter() &&
989            layer->getWidth() == (uint32_t) rect.getWidth() &&
990            layer->getHeight() == (uint32_t) rect.getHeight()) {
991        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
992        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
993
994        layer->setFilter(GL_NEAREST);
995        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
996                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
997    } else {
998        layer->setFilter(GL_LINEAR);
999        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
1000                rect.left, rect.top, rect.right, rect.bottom);
1001    }
1002    setupDrawTextureTransformUniforms(layer->getTexTransform());
1003    setupDrawMesh(&mMeshVertices[0].x, &mMeshVertices[0].u);
1004
1005    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1006}
1007
1008void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
1009    if (!layer->isTextureLayer()) {
1010        const Rect& texCoords = layer->texCoords;
1011        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
1012                texCoords.right, texCoords.bottom);
1013
1014        float x = rect.left;
1015        float y = rect.top;
1016        bool simpleTransform = currentTransform()->isPureTranslate() &&
1017                layer->getWidth() == (uint32_t) rect.getWidth() &&
1018                layer->getHeight() == (uint32_t) rect.getHeight();
1019
1020        if (simpleTransform) {
1021            // When we're swapping, the layer is already in screen coordinates
1022            if (!swap) {
1023                x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
1024                y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
1025            }
1026
1027            layer->setFilter(GL_NEAREST, true);
1028        } else {
1029            layer->setFilter(GL_LINEAR, true);
1030        }
1031
1032        SkPaint layerPaint;
1033        layerPaint.setAlpha(getLayerAlpha(layer) * 255);
1034        layerPaint.setXfermodeMode(layer->getMode());
1035        layerPaint.setColorFilter(layer->getColorFilter());
1036
1037        bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f;
1038        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
1039                layer->getTexture(), &layerPaint, blend,
1040                &mMeshVertices[0].x, &mMeshVertices[0].u,
1041                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
1042
1043        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1044    } else {
1045        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
1046        drawTextureLayer(layer, rect);
1047        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1048    }
1049}
1050
1051/**
1052 * Issues the command X, and if we're composing a save layer to the fbo or drawing a newly updated
1053 * hardware layer with overdraw debug on, draws again to the stencil only, so that these draw
1054 * operations are correctly counted twice for overdraw. NOTE: assumes composeLayerRegion only used
1055 * by saveLayer's restore
1056 */
1057#define DRAW_DOUBLE_STENCIL_IF(COND, DRAW_COMMAND) {                             \
1058        DRAW_COMMAND;                                                            \
1059        if (CC_UNLIKELY(mCaches.debugOverdraw && getTargetFbo() == 0 && COND)) { \
1060            glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);                 \
1061            DRAW_COMMAND;                                                        \
1062            glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);                     \
1063        }                                                                        \
1064    }
1065
1066#define DRAW_DOUBLE_STENCIL(DRAW_COMMAND) DRAW_DOUBLE_STENCIL_IF(true, DRAW_COMMAND)
1067
1068void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
1069    if (CC_UNLIKELY(layer->region.isEmpty())) return; // nothing to draw
1070
1071    if (layer->getConvexMask()) {
1072        save(SkCanvas::kClip_SaveFlag | SkCanvas::kMatrix_SaveFlag);
1073
1074        // clip to the area of the layer the mask can be larger
1075        clipRect(rect.left, rect.top, rect.right, rect.bottom, SkRegion::kIntersect_Op);
1076
1077        SkPaint paint;
1078        paint.setAntiAlias(true);
1079        paint.setColor(SkColorSetARGB(int(getLayerAlpha(layer) * 255), 0, 0, 0));
1080
1081        SkiaShader* oldShader = mDrawModifiers.mShader;
1082
1083        // create LayerShader to map SaveLayer content into subsequent draw
1084        SkMatrix shaderMatrix;
1085        shaderMatrix.setTranslate(rect.left, rect.bottom);
1086        shaderMatrix.preScale(1, -1);
1087        SkiaLayerShader layerShader(layer, &shaderMatrix);
1088        mDrawModifiers.mShader = &layerShader;
1089
1090        // Since the drawing primitive is defined in local drawing space,
1091        // we don't need to modify the draw matrix
1092        const SkPath* maskPath = layer->getConvexMask();
1093        DRAW_DOUBLE_STENCIL(drawConvexPath(*maskPath, &paint));
1094
1095        mDrawModifiers.mShader = oldShader;
1096        restore();
1097
1098        return;
1099    }
1100
1101    if (layer->region.isRect()) {
1102        layer->setRegionAsRect();
1103
1104        DRAW_DOUBLE_STENCIL(composeLayerRect(layer, layer->regionRect));
1105
1106        layer->region.clear();
1107        return;
1108    }
1109
1110    // standard Region based draw
1111    size_t count;
1112    const android::Rect* rects;
1113    Region safeRegion;
1114    if (CC_LIKELY(hasRectToRectTransform())) {
1115        rects = layer->region.getArray(&count);
1116    } else {
1117        safeRegion = Region::createTJunctionFreeRegion(layer->region);
1118        rects = safeRegion.getArray(&count);
1119    }
1120
1121    const float alpha = getLayerAlpha(layer);
1122    const float texX = 1.0f / float(layer->getWidth());
1123    const float texY = 1.0f / float(layer->getHeight());
1124    const float height = rect.getHeight();
1125
1126    setupDraw();
1127
1128    // We must get (and therefore bind) the region mesh buffer
1129    // after we setup drawing in case we need to mess with the
1130    // stencil buffer in setupDraw()
1131    TextureVertex* mesh = mCaches.getRegionMesh();
1132    uint32_t numQuads = 0;
1133
1134    setupDrawWithTexture();
1135    setupDrawColor(alpha, alpha, alpha, alpha);
1136    setupDrawColorFilter(layer->getColorFilter());
1137    setupDrawBlending(layer);
1138    setupDrawProgram();
1139    setupDrawDirtyRegionsDisabled();
1140    setupDrawPureColorUniforms();
1141    setupDrawColorFilterUniforms(layer->getColorFilter());
1142    setupDrawTexture(layer->getTexture());
1143    if (currentTransform()->isPureTranslate()) {
1144        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
1145        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
1146
1147        layer->setFilter(GL_NEAREST);
1148        setupDrawModelView(kModelViewMode_Translate, false,
1149                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1150    } else {
1151        layer->setFilter(GL_LINEAR);
1152        setupDrawModelView(kModelViewMode_Translate, false,
1153                rect.left, rect.top, rect.right, rect.bottom);
1154    }
1155    setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
1156
1157    for (size_t i = 0; i < count; i++) {
1158        const android::Rect* r = &rects[i];
1159
1160        const float u1 = r->left * texX;
1161        const float v1 = (height - r->top) * texY;
1162        const float u2 = r->right * texX;
1163        const float v2 = (height - r->bottom) * texY;
1164
1165        // TODO: Reject quads outside of the clip
1166        TextureVertex::set(mesh++, r->left, r->top, u1, v1);
1167        TextureVertex::set(mesh++, r->right, r->top, u2, v1);
1168        TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
1169        TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
1170
1171        numQuads++;
1172
1173        if (numQuads >= gMaxNumberOfQuads) {
1174            DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1175                            GL_UNSIGNED_SHORT, NULL));
1176            numQuads = 0;
1177            mesh = mCaches.getRegionMesh();
1178        }
1179    }
1180
1181    if (numQuads > 0) {
1182        DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1183                        GL_UNSIGNED_SHORT, NULL));
1184    }
1185
1186#if DEBUG_LAYERS_AS_REGIONS
1187    drawRegionRectsDebug(layer->region);
1188#endif
1189
1190    layer->region.clear();
1191}
1192
1193#if DEBUG_LAYERS_AS_REGIONS
1194void OpenGLRenderer::drawRegionRectsDebug(const Region& region) {
1195    size_t count;
1196    const android::Rect* rects = region.getArray(&count);
1197
1198    uint32_t colors[] = {
1199            0x7fff0000, 0x7f00ff00,
1200            0x7f0000ff, 0x7fff00ff,
1201    };
1202
1203    int offset = 0;
1204    int32_t top = rects[0].top;
1205
1206    for (size_t i = 0; i < count; i++) {
1207        if (top != rects[i].top) {
1208            offset ^= 0x2;
1209            top = rects[i].top;
1210        }
1211
1212        SkPaint paint;
1213        paint.setColor(colors[offset + (i & 0x1)]);
1214        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
1215        drawColorRect(r.left, r.top, r.right, r.bottom, paint);
1216    }
1217}
1218#endif
1219
1220void OpenGLRenderer::drawRegionRects(const SkRegion& region, const SkPaint& paint, bool dirty) {
1221    Vector<float> rects;
1222
1223    SkRegion::Iterator it(region);
1224    while (!it.done()) {
1225        const SkIRect& r = it.rect();
1226        rects.push(r.fLeft);
1227        rects.push(r.fTop);
1228        rects.push(r.fRight);
1229        rects.push(r.fBottom);
1230        it.next();
1231    }
1232
1233    drawColorRects(rects.array(), rects.size(), &paint, true, dirty, false);
1234}
1235
1236void OpenGLRenderer::dirtyLayer(const float left, const float top,
1237        const float right, const float bottom, const mat4 transform) {
1238    if (hasLayer()) {
1239        Rect bounds(left, top, right, bottom);
1240        transform.mapRect(bounds);
1241        dirtyLayerUnchecked(bounds, getRegion());
1242    }
1243}
1244
1245void OpenGLRenderer::dirtyLayer(const float left, const float top,
1246        const float right, const float bottom) {
1247    if (hasLayer()) {
1248        Rect bounds(left, top, right, bottom);
1249        dirtyLayerUnchecked(bounds, getRegion());
1250    }
1251}
1252
1253void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
1254    if (bounds.intersect(*currentClipRect())) {
1255        bounds.snapToPixelBoundaries();
1256        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1257        if (!dirty.isEmpty()) {
1258            region->orSelf(dirty);
1259        }
1260    }
1261}
1262
1263void OpenGLRenderer::issueIndexedQuadDraw(Vertex* mesh, GLsizei quadsCount) {
1264    GLsizei elementsCount = quadsCount * 6;
1265    while (elementsCount > 0) {
1266        GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
1267
1268        setupDrawIndexedVertices(&mesh[0].x);
1269        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL);
1270
1271        elementsCount -= drawCount;
1272        // Though there are 4 vertices in a quad, we use 6 indices per
1273        // quad to draw with GL_TRIANGLES
1274        mesh += (drawCount / 6) * 4;
1275    }
1276}
1277
1278void OpenGLRenderer::clearLayerRegions() {
1279    const size_t count = mLayers.size();
1280    if (count == 0) return;
1281
1282    if (!currentSnapshot()->isIgnored()) {
1283        // Doing several glScissor/glClear here can negatively impact
1284        // GPUs with a tiler architecture, instead we draw quads with
1285        // the Clear blending mode
1286
1287        // The list contains bounds that have already been clipped
1288        // against their initial clip rect, and the current clip
1289        // is likely different so we need to disable clipping here
1290        bool scissorChanged = mCaches.disableScissor();
1291
1292        Vertex mesh[count * 4];
1293        Vertex* vertex = mesh;
1294
1295        for (uint32_t i = 0; i < count; i++) {
1296            Rect* bounds = mLayers.itemAt(i);
1297
1298            Vertex::set(vertex++, bounds->left, bounds->top);
1299            Vertex::set(vertex++, bounds->right, bounds->top);
1300            Vertex::set(vertex++, bounds->left, bounds->bottom);
1301            Vertex::set(vertex++, bounds->right, bounds->bottom);
1302
1303            delete bounds;
1304        }
1305        // We must clear the list of dirty rects before we
1306        // call setupDraw() to prevent stencil setup to do
1307        // the same thing again
1308        mLayers.clear();
1309
1310        SkPaint clearPaint;
1311        clearPaint.setXfermodeMode(SkXfermode::kClear_Mode);
1312
1313        setupDraw(false);
1314        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
1315        setupDrawBlending(&clearPaint, true);
1316        setupDrawProgram();
1317        setupDrawPureColorUniforms();
1318        setupDrawModelView(kModelViewMode_Translate, false,
1319                0.0f, 0.0f, 0.0f, 0.0f, true);
1320
1321        issueIndexedQuadDraw(&mesh[0], count);
1322
1323        if (scissorChanged) mCaches.enableScissor();
1324    } else {
1325        for (uint32_t i = 0; i < count; i++) {
1326            delete mLayers.itemAt(i);
1327        }
1328        mLayers.clear();
1329    }
1330}
1331
1332///////////////////////////////////////////////////////////////////////////////
1333// State Deferral
1334///////////////////////////////////////////////////////////////////////////////
1335
1336bool OpenGLRenderer::storeDisplayState(DeferredDisplayState& state, int stateDeferFlags) {
1337    const Rect* currentClip = currentClipRect();
1338    const mat4* currentMatrix = currentTransform();
1339
1340    if (stateDeferFlags & kStateDeferFlag_Draw) {
1341        // state has bounds initialized in local coordinates
1342        if (!state.mBounds.isEmpty()) {
1343            currentMatrix->mapRect(state.mBounds);
1344            Rect clippedBounds(state.mBounds);
1345            // NOTE: if we ever want to use this clipping info to drive whether the scissor
1346            // is used, it should more closely duplicate the quickReject logic (in how it uses
1347            // snapToPixelBoundaries)
1348
1349            if(!clippedBounds.intersect(*currentClip)) {
1350                // quick rejected
1351                return true;
1352            }
1353
1354            state.mClipSideFlags = kClipSide_None;
1355            if (!currentClip->contains(state.mBounds)) {
1356                int& flags = state.mClipSideFlags;
1357                // op partially clipped, so record which sides are clipped for clip-aware merging
1358                if (currentClip->left > state.mBounds.left) flags |= kClipSide_Left;
1359                if (currentClip->top > state.mBounds.top) flags |= kClipSide_Top;
1360                if (currentClip->right < state.mBounds.right) flags |= kClipSide_Right;
1361                if (currentClip->bottom < state.mBounds.bottom) flags |= kClipSide_Bottom;
1362            }
1363            state.mBounds.set(clippedBounds);
1364        } else {
1365            // Empty bounds implies size unknown. Label op as conservatively clipped to disable
1366            // overdraw avoidance (since we don't know what it overlaps)
1367            state.mClipSideFlags = kClipSide_ConservativeFull;
1368            state.mBounds.set(*currentClip);
1369        }
1370    }
1371
1372    state.mClipValid = (stateDeferFlags & kStateDeferFlag_Clip);
1373    if (state.mClipValid) {
1374        state.mClip.set(*currentClip);
1375    }
1376
1377    // Transform, drawModifiers, and alpha always deferred, since they are used by state operations
1378    // (Note: saveLayer/restore use colorFilter and alpha, so we just save restore everything)
1379    state.mMatrix.load(*currentMatrix);
1380    state.mDrawModifiers = mDrawModifiers;
1381    state.mAlpha = currentSnapshot()->alpha;
1382    return false;
1383}
1384
1385void OpenGLRenderer::restoreDisplayState(const DeferredDisplayState& state, bool skipClipRestore) {
1386    setMatrix(state.mMatrix);
1387    mSnapshot->alpha = state.mAlpha;
1388    mDrawModifiers = state.mDrawModifiers;
1389
1390    if (state.mClipValid && !skipClipRestore) {
1391        mSnapshot->setClip(state.mClip.left, state.mClip.top,
1392                state.mClip.right, state.mClip.bottom);
1393        dirtyClip();
1394    }
1395}
1396
1397/**
1398 * Merged multidraw (such as in drawText and drawBitmaps rely on the fact that no clipping is done
1399 * in the draw path. Instead, clipping is done ahead of time - either as a single clip rect (when at
1400 * least one op is clipped), or disabled entirely (because no merged op is clipped)
1401 *
1402 * This method should be called when restoreDisplayState() won't be restoring the clip
1403 */
1404void OpenGLRenderer::setupMergedMultiDraw(const Rect* clipRect) {
1405    if (clipRect != NULL) {
1406        mSnapshot->setClip(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
1407    } else {
1408        mSnapshot->setClip(0, 0, getWidth(), getHeight());
1409    }
1410    dirtyClip();
1411    mCaches.setScissorEnabled(clipRect != NULL || mScissorOptimizationDisabled);
1412}
1413
1414///////////////////////////////////////////////////////////////////////////////
1415// Clipping
1416///////////////////////////////////////////////////////////////////////////////
1417
1418void OpenGLRenderer::setScissorFromClip() {
1419    Rect clip(*currentClipRect());
1420    clip.snapToPixelBoundaries();
1421
1422    if (mCaches.setScissor(clip.left, currentSnapshot()->height - clip.bottom,
1423            clip.getWidth(), clip.getHeight())) {
1424        mDirtyClip = false;
1425    }
1426}
1427
1428void OpenGLRenderer::ensureStencilBuffer() {
1429    // Thanks to the mismatch between EGL and OpenGL ES FBO we
1430    // cannot attach a stencil buffer to fbo0 dynamically. Let's
1431    // just hope we have one when hasLayer() returns false.
1432    if (hasLayer()) {
1433        attachStencilBufferToLayer(currentSnapshot()->layer);
1434    }
1435}
1436
1437void OpenGLRenderer::attachStencilBufferToLayer(Layer* layer) {
1438    // The layer's FBO is already bound when we reach this stage
1439    if (!layer->getStencilRenderBuffer()) {
1440        // GL_QCOM_tiled_rendering doesn't like it if a renderbuffer
1441        // is attached after we initiated tiling. We must turn it off,
1442        // attach the new render buffer then turn tiling back on
1443        endTiling();
1444
1445        RenderBuffer* buffer = mCaches.renderBufferCache.get(
1446                Stencil::getSmallestStencilFormat(), layer->getWidth(), layer->getHeight());
1447        layer->setStencilRenderBuffer(buffer);
1448
1449        startTiling(layer->clipRect, layer->layer.getHeight());
1450    }
1451}
1452
1453void OpenGLRenderer::setStencilFromClip() {
1454    if (!mCaches.debugOverdraw) {
1455        if (!currentSnapshot()->clipRegion->isEmpty()) {
1456            // NOTE: The order here is important, we must set dirtyClip to false
1457            //       before any draw call to avoid calling back into this method
1458            mDirtyClip = false;
1459
1460            ensureStencilBuffer();
1461
1462            mCaches.stencil.enableWrite();
1463
1464            // Clear the stencil but first make sure we restrict drawing
1465            // to the region's bounds
1466            bool resetScissor = mCaches.enableScissor();
1467            if (resetScissor) {
1468                // The scissor was not set so we now need to update it
1469                setScissorFromClip();
1470            }
1471            mCaches.stencil.clear();
1472            if (resetScissor) mCaches.disableScissor();
1473
1474            SkPaint paint;
1475            paint.setColor(0xff000000);
1476            paint.setXfermodeMode(SkXfermode::kSrc_Mode);
1477
1478            // NOTE: We could use the region contour path to generate a smaller mesh
1479            //       Since we are using the stencil we could use the red book path
1480            //       drawing technique. It might increase bandwidth usage though.
1481
1482            // The last parameter is important: we are not drawing in the color buffer
1483            // so we don't want to dirty the current layer, if any
1484            drawRegionRects(*(currentSnapshot()->clipRegion), paint, false);
1485
1486            mCaches.stencil.enableTest();
1487
1488            // Draw the region used to generate the stencil if the appropriate debug
1489            // mode is enabled
1490            if (mCaches.debugStencilClip == Caches::kStencilShowRegion) {
1491                paint.setColor(0x7f0000ff);
1492                paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
1493                drawRegionRects(*(currentSnapshot()->clipRegion), paint);
1494            }
1495        } else {
1496            mCaches.stencil.disable();
1497        }
1498    }
1499}
1500
1501/**
1502 * Returns false and sets scissor enable based upon bounds if drawing won't be clipped out.
1503 *
1504 * @param paint if not null, the bounds will be expanded to account for stroke depending on paint
1505 *         style, and tessellated AA ramp
1506 */
1507bool OpenGLRenderer::quickRejectSetupScissor(float left, float top, float right, float bottom,
1508        const SkPaint* paint) {
1509    bool clipRequired = false;
1510    bool snapOut = paint && paint->isAntiAlias();
1511
1512    if (paint && paint->getStyle() != SkPaint::kFill_Style) {
1513        float outset = paint->getStrokeWidth() * 0.5f;
1514        left -= outset;
1515        top -= outset;
1516        right += outset;
1517        bottom += outset;
1518    }
1519
1520    if (calculateQuickRejectForScissor(left, top, right, bottom, &clipRequired, snapOut)) {
1521        return true;
1522    }
1523
1524    if (!isRecording()) {
1525        // not quick rejected, so enable the scissor if clipRequired
1526        mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
1527    }
1528    return false;
1529}
1530
1531void OpenGLRenderer::debugClip() {
1532#if DEBUG_CLIP_REGIONS
1533    if (!isRecording() && !currentSnapshot()->clipRegion->isEmpty()) {
1534        SkPaint paint;
1535        paint.setColor(0x7f00ff00);
1536        drawRegionRects(*(currentSnapshot()->clipRegion, paint);
1537
1538    }
1539#endif
1540}
1541
1542///////////////////////////////////////////////////////////////////////////////
1543// Drawing commands
1544///////////////////////////////////////////////////////////////////////////////
1545
1546void OpenGLRenderer::setupDraw(bool clear) {
1547    // TODO: It would be best if we could do this before quickRejectSetupScissor()
1548    //       changes the scissor test state
1549    if (clear) clearLayerRegions();
1550    // Make sure setScissor & setStencil happen at the beginning of
1551    // this method
1552    if (mDirtyClip) {
1553        if (mCaches.scissorEnabled) {
1554            setScissorFromClip();
1555        }
1556        setStencilFromClip();
1557    }
1558
1559    mDescription.reset();
1560
1561    mSetShaderColor = false;
1562    mColorSet = false;
1563    mColorA = mColorR = mColorG = mColorB = 0.0f;
1564    mTextureUnit = 0;
1565    mTrackDirtyRegions = true;
1566
1567    // Enable debug highlight when what we're about to draw is tested against
1568    // the stencil buffer and if stencil highlight debugging is on
1569    mDescription.hasDebugHighlight = !mCaches.debugOverdraw &&
1570            mCaches.debugStencilClip == Caches::kStencilShowHighlight &&
1571            mCaches.stencil.isTestEnabled();
1572
1573    mDescription.emulateStencil = mCountOverdraw;
1574}
1575
1576void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1577    mDescription.hasTexture = true;
1578    mDescription.hasAlpha8Texture = isAlpha8;
1579}
1580
1581void OpenGLRenderer::setupDrawWithTextureAndColor(bool isAlpha8) {
1582    mDescription.hasTexture = true;
1583    mDescription.hasColors = true;
1584    mDescription.hasAlpha8Texture = isAlpha8;
1585}
1586
1587void OpenGLRenderer::setupDrawWithExternalTexture() {
1588    mDescription.hasExternalTexture = true;
1589}
1590
1591void OpenGLRenderer::setupDrawNoTexture() {
1592    mCaches.disableTexCoordsVertexArray();
1593}
1594
1595void OpenGLRenderer::setupDrawAA() {
1596    mDescription.isAA = true;
1597}
1598
1599void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1600    mColorA = alpha / 255.0f;
1601    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1602    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1603    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1604    mColorSet = true;
1605    mSetShaderColor = mDescription.setColorModulate(mColorA);
1606}
1607
1608void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1609    mColorA = alpha / 255.0f;
1610    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1611    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1612    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1613    mColorSet = true;
1614    mSetShaderColor = mDescription.setAlpha8ColorModulate(mColorR, mColorG, mColorB, mColorA);
1615}
1616
1617void OpenGLRenderer::setupDrawTextGamma(const SkPaint* paint) {
1618    mCaches.fontRenderer->describe(mDescription, paint);
1619}
1620
1621void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1622    mColorA = a;
1623    mColorR = r;
1624    mColorG = g;
1625    mColorB = b;
1626    mColorSet = true;
1627    mSetShaderColor = mDescription.setColorModulate(a);
1628}
1629
1630void OpenGLRenderer::setupDrawShader() {
1631    if (mDrawModifiers.mShader) {
1632        mDrawModifiers.mShader->describe(mDescription, mExtensions);
1633    }
1634}
1635
1636void OpenGLRenderer::setupDrawColorFilter(const SkColorFilter* filter) {
1637    if (filter == NULL) {
1638        return;
1639    }
1640
1641    SkXfermode::Mode mode;
1642    if (filter->asColorMode(NULL, &mode)) {
1643        mDescription.colorOp = ProgramDescription::kColorBlend;
1644        mDescription.colorMode = mode;
1645    } else if (filter->asColorMatrix(NULL)) {
1646        mDescription.colorOp = ProgramDescription::kColorMatrix;
1647    }
1648}
1649
1650void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1651    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1652        mColorA = 1.0f;
1653        mColorR = mColorG = mColorB = 0.0f;
1654        mSetShaderColor = mDescription.modulate = true;
1655    }
1656}
1657
1658void OpenGLRenderer::setupDrawBlending(const Layer* layer, bool swapSrcDst) {
1659    SkXfermode::Mode mode = layer->getMode();
1660    // When the blending mode is kClear_Mode, we need to use a modulate color
1661    // argb=1,0,0,0
1662    accountForClear(mode);
1663    bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f ||
1664            (mColorSet && mColorA < 1.0f) ||
1665            (mDrawModifiers.mShader && mDrawModifiers.mShader->blend()) ||
1666            layer->getColorFilter();
1667    chooseBlending(blend, mode, mDescription, swapSrcDst);
1668}
1669
1670void OpenGLRenderer::setupDrawBlending(const SkPaint* paint, bool blend, bool swapSrcDst) {
1671    SkXfermode::Mode mode = getXfermodeDirect(paint);
1672    // When the blending mode is kClear_Mode, we need to use a modulate color
1673    // argb=1,0,0,0
1674    accountForClear(mode);
1675    blend |= (mColorSet && mColorA < 1.0f) ||
1676            (mDrawModifiers.mShader && mDrawModifiers.mShader->blend()) ||
1677            (paint && paint->getColorFilter());
1678    chooseBlending(blend, mode, mDescription, swapSrcDst);
1679}
1680
1681void OpenGLRenderer::setupDrawProgram() {
1682    useProgram(mCaches.programCache.get(mDescription));
1683}
1684
1685void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1686    mTrackDirtyRegions = false;
1687}
1688
1689void OpenGLRenderer::setupDrawModelView(ModelViewMode mode, bool offset,
1690        float left, float top, float right, float bottom, bool ignoreTransform) {
1691    mModelViewMatrix.loadTranslate(left, top, 0.0f);
1692    if (mode == kModelViewMode_TranslateAndScale) {
1693        mModelViewMatrix.scale(right - left, bottom - top, 1.0f);
1694    }
1695
1696    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1697    if (!ignoreTransform) {
1698        mCaches.currentProgram->set(mProjectionMatrix, mModelViewMatrix, *currentTransform(), offset);
1699        if (dirty && mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *currentTransform());
1700    } else {
1701        mCaches.currentProgram->set(mProjectionMatrix, mModelViewMatrix, mat4::identity(), offset);
1702        if (dirty && mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
1703    }
1704}
1705
1706void OpenGLRenderer::setupDrawColorUniforms() {
1707    if ((mColorSet && !mDrawModifiers.mShader) || (mDrawModifiers.mShader && mSetShaderColor)) {
1708        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1709    }
1710}
1711
1712void OpenGLRenderer::setupDrawPureColorUniforms() {
1713    if (mSetShaderColor) {
1714        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1715    }
1716}
1717
1718void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1719    if (mDrawModifiers.mShader) {
1720        if (ignoreTransform) {
1721            // if ignoreTransform=true was passed to setupDrawModelView, undo currentTransform()
1722            // because it was built into modelView / the geometry, and the SkiaShader needs to
1723            // compensate.
1724            mat4 modelViewWithoutTransform;
1725            modelViewWithoutTransform.loadInverse(*currentTransform());
1726            modelViewWithoutTransform.multiply(mModelViewMatrix);
1727            mModelViewMatrix.load(modelViewWithoutTransform);
1728        }
1729        mDrawModifiers.mShader->setupProgram(mCaches.currentProgram,
1730                mModelViewMatrix, *mSnapshot, &mTextureUnit);
1731    }
1732}
1733
1734void OpenGLRenderer::setupDrawColorFilterUniforms(const SkColorFilter* filter) {
1735    if (NULL == filter) {
1736        return;
1737    }
1738
1739    SkColor color;
1740    SkXfermode::Mode mode;
1741    if (filter->asColorMode(&color, &mode)) {
1742        const int alpha = SkColorGetA(color);
1743        const GLfloat a = alpha / 255.0f;
1744        const GLfloat r = a * SkColorGetR(color) / 255.0f;
1745        const GLfloat g = a * SkColorGetG(color) / 255.0f;
1746        const GLfloat b = a * SkColorGetB(color) / 255.0f;
1747        glUniform4f(mCaches.currentProgram->getUniform("colorBlend"), r, g, b, a);
1748        return;
1749    }
1750
1751    SkScalar srcColorMatrix[20];
1752    if (filter->asColorMatrix(srcColorMatrix)) {
1753
1754        float colorMatrix[16];
1755        memcpy(colorMatrix, srcColorMatrix, 4 * sizeof(float));
1756        memcpy(&colorMatrix[4], &srcColorMatrix[5], 4 * sizeof(float));
1757        memcpy(&colorMatrix[8], &srcColorMatrix[10], 4 * sizeof(float));
1758        memcpy(&colorMatrix[12], &srcColorMatrix[15], 4 * sizeof(float));
1759
1760        // Skia uses the range [0..255] for the addition vector, but we need
1761        // the [0..1] range to apply the vector in GLSL
1762        float colorVector[4];
1763        colorVector[0] = srcColorMatrix[4] / 255.0f;
1764        colorVector[1] = srcColorMatrix[9] / 255.0f;
1765        colorVector[2] = srcColorMatrix[14] / 255.0f;
1766        colorVector[3] = srcColorMatrix[19] / 255.0f;
1767
1768        glUniformMatrix4fv(mCaches.currentProgram->getUniform("colorMatrix"), 1,
1769                GL_FALSE, colorMatrix);
1770        glUniform4fv(mCaches.currentProgram->getUniform("colorMatrixVector"), 1, colorVector);
1771        return;
1772    }
1773
1774    // it is an error if we ever get here
1775}
1776
1777void OpenGLRenderer::setupDrawTextGammaUniforms() {
1778    mCaches.fontRenderer->setupProgram(mDescription, mCaches.currentProgram);
1779}
1780
1781void OpenGLRenderer::setupDrawSimpleMesh() {
1782    bool force = mCaches.bindMeshBuffer();
1783    mCaches.bindPositionVertexPointer(force, 0);
1784    mCaches.unbindIndicesBuffer();
1785}
1786
1787void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1788    if (texture) bindTexture(texture);
1789    mTextureUnit++;
1790    mCaches.enableTexCoordsVertexArray();
1791}
1792
1793void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1794    bindExternalTexture(texture);
1795    mTextureUnit++;
1796    mCaches.enableTexCoordsVertexArray();
1797}
1798
1799void OpenGLRenderer::setupDrawTextureTransform() {
1800    mDescription.hasTextureTransform = true;
1801}
1802
1803void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1804    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1805            GL_FALSE, &transform.data[0]);
1806}
1807
1808void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1809        const GLvoid* texCoords, GLuint vbo) {
1810    bool force = false;
1811    if (!vertices || vbo) {
1812        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1813    } else {
1814        force = mCaches.unbindMeshBuffer();
1815    }
1816
1817    mCaches.bindPositionVertexPointer(force, vertices);
1818    if (mCaches.currentProgram->texCoords >= 0) {
1819        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1820    }
1821
1822    mCaches.unbindIndicesBuffer();
1823}
1824
1825void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1826        const GLvoid* texCoords, const GLvoid* colors) {
1827    bool force = mCaches.unbindMeshBuffer();
1828    GLsizei stride = sizeof(ColorTextureVertex);
1829
1830    mCaches.bindPositionVertexPointer(force, vertices, stride);
1831    if (mCaches.currentProgram->texCoords >= 0) {
1832        mCaches.bindTexCoordsVertexPointer(force, texCoords, stride);
1833    }
1834    int slot = mCaches.currentProgram->getAttrib("colors");
1835    if (slot >= 0) {
1836        glEnableVertexAttribArray(slot);
1837        glVertexAttribPointer(slot, 4, GL_FLOAT, GL_FALSE, stride, colors);
1838    }
1839
1840    mCaches.unbindIndicesBuffer();
1841}
1842
1843void OpenGLRenderer::setupDrawMeshIndices(const GLvoid* vertices,
1844        const GLvoid* texCoords, GLuint vbo) {
1845    bool force = false;
1846    // If vbo is != 0 we want to treat the vertices parameter as an offset inside
1847    // a VBO. However, if vertices is set to NULL and vbo == 0 then we want to
1848    // use the default VBO found in Caches
1849    if (!vertices || vbo) {
1850        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1851    } else {
1852        force = mCaches.unbindMeshBuffer();
1853    }
1854    mCaches.bindQuadIndicesBuffer();
1855
1856    mCaches.bindPositionVertexPointer(force, vertices);
1857    if (mCaches.currentProgram->texCoords >= 0) {
1858        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1859    }
1860}
1861
1862void OpenGLRenderer::setupDrawIndexedVertices(GLvoid* vertices) {
1863    bool force = mCaches.unbindMeshBuffer();
1864    mCaches.bindQuadIndicesBuffer();
1865    mCaches.bindPositionVertexPointer(force, vertices, gVertexStride);
1866}
1867
1868///////////////////////////////////////////////////////////////////////////////
1869// Drawing
1870///////////////////////////////////////////////////////////////////////////////
1871
1872status_t OpenGLRenderer::drawDisplayList(RenderNode* displayList, Rect& dirty,
1873        int32_t replayFlags) {
1874    status_t status;
1875    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1876    // will be performed by the display list itself
1877    if (displayList && displayList->isRenderable()) {
1878        // compute 3d ordering
1879        displayList->computeOrdering();
1880        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
1881            status = startFrame();
1882            ReplayStateStruct replayStruct(*this, dirty, replayFlags);
1883            displayList->replayNodeTree(replayStruct);
1884            return status | replayStruct.mDrawGlStatus;
1885        }
1886
1887        bool avoidOverdraw = !mCaches.debugOverdraw && !mCountOverdraw; // shh, don't tell devs!
1888        DeferredDisplayList deferredList(*currentClipRect(), avoidOverdraw);
1889        DeferStateStruct deferStruct(deferredList, *this, replayFlags);
1890        displayList->deferNodeTree(deferStruct);
1891
1892        flushLayers();
1893        status = startFrame();
1894
1895        return deferredList.flush(*this, dirty) | status;
1896    }
1897
1898    return DrawGlInfo::kStatusDone;
1899}
1900
1901void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, const SkPaint* paint) {
1902    int color = paint != NULL ? paint->getColor() : 0;
1903
1904    float x = left;
1905    float y = top;
1906
1907    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1908
1909    bool ignoreTransform = false;
1910    if (currentTransform()->isPureTranslate()) {
1911        x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
1912        y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
1913        ignoreTransform = true;
1914
1915        texture->setFilter(GL_NEAREST, true);
1916    } else {
1917        texture->setFilter(getFilter(paint), true);
1918    }
1919
1920    // No need to check for a UV mapper on the texture object, only ARGB_8888
1921    // bitmaps get packed in the atlas
1922    drawAlpha8TextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1923            paint, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1924            GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
1925}
1926
1927/**
1928 * Important note: this method is intended to draw batches of bitmaps and
1929 * will not set the scissor enable or dirty the current layer, if any.
1930 * The caller is responsible for properly dirtying the current layer.
1931 */
1932status_t OpenGLRenderer::drawBitmaps(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
1933        int bitmapCount, TextureVertex* vertices, bool pureTranslate,
1934        const Rect& bounds, const SkPaint* paint) {
1935    mCaches.activeTexture(0);
1936    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
1937    if (!texture) return DrawGlInfo::kStatusDone;
1938
1939    const AutoTexture autoCleanup(texture);
1940
1941    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1942    texture->setFilter(pureTranslate ? GL_NEAREST : getFilter(paint), true);
1943
1944    const float x = (int) floorf(bounds.left + 0.5f);
1945    const float y = (int) floorf(bounds.top + 0.5f);
1946    if (CC_UNLIKELY(bitmap->config() == SkBitmap::kA8_Config)) {
1947        drawAlpha8TextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1948                texture->id, paint, &vertices[0].x, &vertices[0].u,
1949                GL_TRIANGLES, bitmapCount * 6, true,
1950                kModelViewMode_Translate, false);
1951    } else {
1952        drawTextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1953                texture->id, paint, texture->blend, &vertices[0].x, &vertices[0].u,
1954                GL_TRIANGLES, bitmapCount * 6, false, true, 0,
1955                kModelViewMode_Translate, false);
1956    }
1957
1958    return DrawGlInfo::kStatusDrew;
1959}
1960
1961status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap, float left, float top,
1962        const SkPaint* paint) {
1963    const float right = left + bitmap->width();
1964    const float bottom = top + bitmap->height();
1965
1966    if (quickRejectSetupScissor(left, top, right, bottom)) {
1967        return DrawGlInfo::kStatusDone;
1968    }
1969
1970    mCaches.activeTexture(0);
1971    Texture* texture = getTexture(bitmap);
1972    if (!texture) return DrawGlInfo::kStatusDone;
1973    const AutoTexture autoCleanup(texture);
1974
1975    if (CC_UNLIKELY(bitmap->config() == SkBitmap::kA8_Config)) {
1976        drawAlphaBitmap(texture, left, top, paint);
1977    } else {
1978        drawTextureRect(left, top, right, bottom, texture, paint);
1979    }
1980
1981    return DrawGlInfo::kStatusDrew;
1982}
1983
1984status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap, const SkMatrix* matrix,
1985        const SkPaint* paint) {
1986    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1987    const mat4 transform(*matrix);
1988    transform.mapRect(r);
1989
1990    if (quickRejectSetupScissor(r.left, r.top, r.right, r.bottom)) {
1991        return DrawGlInfo::kStatusDone;
1992    }
1993
1994    mCaches.activeTexture(0);
1995    Texture* texture = getTexture(bitmap);
1996    if (!texture) return DrawGlInfo::kStatusDone;
1997    const AutoTexture autoCleanup(texture);
1998
1999    // This could be done in a cheaper way, all we need is pass the matrix
2000    // to the vertex shader. The save/restore is a bit overkill.
2001    save(SkCanvas::kMatrix_SaveFlag);
2002    concatMatrix(matrix);
2003    if (CC_UNLIKELY(bitmap->config() == SkBitmap::kA8_Config)) {
2004        drawAlphaBitmap(texture, 0.0f, 0.0f, paint);
2005    } else {
2006        drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
2007    }
2008    restore();
2009
2010    return DrawGlInfo::kStatusDrew;
2011}
2012
2013status_t OpenGLRenderer::drawBitmapData(const SkBitmap* bitmap, float left, float top,
2014        const SkPaint* paint) {
2015    const float right = left + bitmap->width();
2016    const float bottom = top + bitmap->height();
2017
2018    if (quickRejectSetupScissor(left, top, right, bottom)) {
2019        return DrawGlInfo::kStatusDone;
2020    }
2021
2022    mCaches.activeTexture(0);
2023    Texture* texture = mCaches.textureCache.getTransient(bitmap);
2024    const AutoTexture autoCleanup(texture);
2025
2026    if (CC_UNLIKELY(bitmap->config() == SkBitmap::kA8_Config)) {
2027        drawAlphaBitmap(texture, left, top, paint);
2028    } else {
2029        drawTextureRect(left, top, right, bottom, texture, paint);
2030    }
2031
2032    return DrawGlInfo::kStatusDrew;
2033}
2034
2035status_t OpenGLRenderer::drawBitmapMesh(const SkBitmap* bitmap, int meshWidth, int meshHeight,
2036        const float* vertices, const int* colors, const SkPaint* paint) {
2037    if (!vertices || currentSnapshot()->isIgnored()) {
2038        return DrawGlInfo::kStatusDone;
2039    }
2040
2041    // TODO: use quickReject on bounds from vertices
2042    mCaches.enableScissor();
2043
2044    float left = FLT_MAX;
2045    float top = FLT_MAX;
2046    float right = FLT_MIN;
2047    float bottom = FLT_MIN;
2048
2049    const uint32_t count = meshWidth * meshHeight * 6;
2050
2051    Vector<ColorTextureVertex> mesh; // TODO: use C++11 unique_ptr
2052    mesh.setCapacity(count);
2053    ColorTextureVertex* vertex = mesh.editArray();
2054
2055    bool cleanupColors = false;
2056    if (!colors) {
2057        uint32_t colorsCount = (meshWidth + 1) * (meshHeight + 1);
2058        int* newColors = new int[colorsCount];
2059        memset(newColors, 0xff, colorsCount * sizeof(int));
2060        colors = newColors;
2061        cleanupColors = true;
2062    }
2063
2064    mCaches.activeTexture(0);
2065    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
2066    const UvMapper& mapper(getMapper(texture));
2067
2068    for (int32_t y = 0; y < meshHeight; y++) {
2069        for (int32_t x = 0; x < meshWidth; x++) {
2070            uint32_t i = (y * (meshWidth + 1) + x) * 2;
2071
2072            float u1 = float(x) / meshWidth;
2073            float u2 = float(x + 1) / meshWidth;
2074            float v1 = float(y) / meshHeight;
2075            float v2 = float(y + 1) / meshHeight;
2076
2077            mapper.map(u1, v1, u2, v2);
2078
2079            int ax = i + (meshWidth + 1) * 2;
2080            int ay = ax + 1;
2081            int bx = i;
2082            int by = bx + 1;
2083            int cx = i + 2;
2084            int cy = cx + 1;
2085            int dx = i + (meshWidth + 1) * 2 + 2;
2086            int dy = dx + 1;
2087
2088            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2089            ColorTextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2, colors[ax / 2]);
2090            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2091
2092            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2093            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2094            ColorTextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1, colors[cx / 2]);
2095
2096            left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
2097            top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
2098            right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
2099            bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
2100        }
2101    }
2102
2103    if (quickRejectSetupScissor(left, top, right, bottom)) {
2104        if (cleanupColors) delete[] colors;
2105        return DrawGlInfo::kStatusDone;
2106    }
2107
2108    if (!texture) {
2109        texture = mCaches.textureCache.get(bitmap);
2110        if (!texture) {
2111            if (cleanupColors) delete[] colors;
2112            return DrawGlInfo::kStatusDone;
2113        }
2114    }
2115    const AutoTexture autoCleanup(texture);
2116
2117    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2118    texture->setFilter(getFilter(paint), true);
2119
2120    int alpha;
2121    SkXfermode::Mode mode;
2122    getAlphaAndMode(paint, &alpha, &mode);
2123
2124    float a = alpha / 255.0f;
2125
2126    if (hasLayer()) {
2127        dirtyLayer(left, top, right, bottom, *currentTransform());
2128    }
2129
2130    setupDraw();
2131    setupDrawWithTextureAndColor();
2132    setupDrawColor(a, a, a, a);
2133    setupDrawColorFilter(getColorFilter(paint));
2134    setupDrawBlending(paint, true);
2135    setupDrawProgram();
2136    setupDrawDirtyRegionsDisabled();
2137    setupDrawModelView(kModelViewMode_TranslateAndScale, false, 0.0f, 0.0f, 1.0f, 1.0f);
2138    setupDrawTexture(texture->id);
2139    setupDrawPureColorUniforms();
2140    setupDrawColorFilterUniforms(getColorFilter(paint));
2141    setupDrawMesh(&mesh[0].x, &mesh[0].u, &mesh[0].r);
2142
2143    glDrawArrays(GL_TRIANGLES, 0, count);
2144
2145    int slot = mCaches.currentProgram->getAttrib("colors");
2146    if (slot >= 0) {
2147        glDisableVertexAttribArray(slot);
2148    }
2149
2150    if (cleanupColors) delete[] colors;
2151
2152    return DrawGlInfo::kStatusDrew;
2153}
2154
2155status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap,
2156         float srcLeft, float srcTop, float srcRight, float srcBottom,
2157         float dstLeft, float dstTop, float dstRight, float dstBottom,
2158         const SkPaint* paint) {
2159    if (quickRejectSetupScissor(dstLeft, dstTop, dstRight, dstBottom)) {
2160        return DrawGlInfo::kStatusDone;
2161    }
2162
2163    mCaches.activeTexture(0);
2164    Texture* texture = getTexture(bitmap);
2165    if (!texture) return DrawGlInfo::kStatusDone;
2166    const AutoTexture autoCleanup(texture);
2167
2168    const float width = texture->width;
2169    const float height = texture->height;
2170
2171    float u1 = fmax(0.0f, srcLeft / width);
2172    float v1 = fmax(0.0f, srcTop / height);
2173    float u2 = fmin(1.0f, srcRight / width);
2174    float v2 = fmin(1.0f, srcBottom / height);
2175
2176    getMapper(texture).map(u1, v1, u2, v2);
2177
2178    mCaches.unbindMeshBuffer();
2179    resetDrawTextureTexCoords(u1, v1, u2, v2);
2180
2181    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2182
2183    float scaleX = (dstRight - dstLeft) / (srcRight - srcLeft);
2184    float scaleY = (dstBottom - dstTop) / (srcBottom - srcTop);
2185
2186    bool scaled = scaleX != 1.0f || scaleY != 1.0f;
2187    // Apply a scale transform on the canvas only when a shader is in use
2188    // Skia handles the ratio between the dst and src rects as a scale factor
2189    // when a shader is set
2190    bool useScaleTransform = mDrawModifiers.mShader && scaled;
2191    bool ignoreTransform = false;
2192
2193    if (CC_LIKELY(currentTransform()->isPureTranslate() && !useScaleTransform)) {
2194        float x = (int) floorf(dstLeft + currentTransform()->getTranslateX() + 0.5f);
2195        float y = (int) floorf(dstTop + currentTransform()->getTranslateY() + 0.5f);
2196
2197        dstRight = x + (dstRight - dstLeft);
2198        dstBottom = y + (dstBottom - dstTop);
2199
2200        dstLeft = x;
2201        dstTop = y;
2202
2203        texture->setFilter(scaled ? getFilter(paint) : GL_NEAREST, true);
2204        ignoreTransform = true;
2205    } else {
2206        texture->setFilter(getFilter(paint), true);
2207    }
2208
2209    if (CC_UNLIKELY(useScaleTransform)) {
2210        save(SkCanvas::kMatrix_SaveFlag);
2211        translate(dstLeft, dstTop);
2212        scale(scaleX, scaleY);
2213
2214        dstLeft = 0.0f;
2215        dstTop = 0.0f;
2216
2217        dstRight = srcRight - srcLeft;
2218        dstBottom = srcBottom - srcTop;
2219    }
2220
2221    if (CC_UNLIKELY(bitmap->config() == SkBitmap::kA8_Config)) {
2222        drawAlpha8TextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2223                texture->id, paint,
2224                &mMeshVertices[0].x, &mMeshVertices[0].u,
2225                GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
2226    } else {
2227        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2228                texture->id, paint, texture->blend,
2229                &mMeshVertices[0].x, &mMeshVertices[0].u,
2230                GL_TRIANGLE_STRIP, gMeshCount, false, ignoreTransform);
2231    }
2232
2233    if (CC_UNLIKELY(useScaleTransform)) {
2234        restore();
2235    }
2236
2237    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
2238
2239    return DrawGlInfo::kStatusDrew;
2240}
2241
2242status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Res_png_9patch* patch,
2243        float left, float top, float right, float bottom, const SkPaint* paint) {
2244    if (quickRejectSetupScissor(left, top, right, bottom)) {
2245        return DrawGlInfo::kStatusDone;
2246    }
2247
2248    AssetAtlas::Entry* entry = mCaches.assetAtlas.getEntry(bitmap);
2249    const Patch* mesh = mCaches.patchCache.get(entry, bitmap->width(), bitmap->height(),
2250            right - left, bottom - top, patch);
2251
2252    return drawPatch(bitmap, mesh, entry, left, top, right, bottom, paint);
2253}
2254
2255status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Patch* mesh,
2256        AssetAtlas::Entry* entry, float left, float top, float right, float bottom,
2257        const SkPaint* paint) {
2258    if (quickRejectSetupScissor(left, top, right, bottom)) {
2259        return DrawGlInfo::kStatusDone;
2260    }
2261
2262    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
2263        mCaches.activeTexture(0);
2264        Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2265        if (!texture) return DrawGlInfo::kStatusDone;
2266        const AutoTexture autoCleanup(texture);
2267
2268        texture->setWrap(GL_CLAMP_TO_EDGE, true);
2269        texture->setFilter(GL_LINEAR, true);
2270
2271        const bool pureTranslate = currentTransform()->isPureTranslate();
2272        // Mark the current layer dirty where we are going to draw the patch
2273        if (hasLayer() && mesh->hasEmptyQuads) {
2274            const float offsetX = left + currentTransform()->getTranslateX();
2275            const float offsetY = top + currentTransform()->getTranslateY();
2276            const size_t count = mesh->quads.size();
2277            for (size_t i = 0; i < count; i++) {
2278                const Rect& bounds = mesh->quads.itemAt(i);
2279                if (CC_LIKELY(pureTranslate)) {
2280                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
2281                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
2282                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
2283                } else {
2284                    dirtyLayer(left + bounds.left, top + bounds.top,
2285                            left + bounds.right, top + bounds.bottom, *currentTransform());
2286                }
2287            }
2288        }
2289
2290        bool ignoreTransform = false;
2291        if (CC_LIKELY(pureTranslate)) {
2292            const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
2293            const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
2294
2295            right = x + right - left;
2296            bottom = y + bottom - top;
2297            left = x;
2298            top = y;
2299            ignoreTransform = true;
2300        }
2301        drawIndexedTextureMesh(left, top, right, bottom, texture->id, paint,
2302                texture->blend, (GLvoid*) mesh->offset, (GLvoid*) mesh->textureOffset,
2303                GL_TRIANGLES, mesh->indexCount, false, ignoreTransform,
2304                mCaches.patchCache.getMeshBuffer(), kModelViewMode_Translate, !mesh->hasEmptyQuads);
2305    }
2306
2307    return DrawGlInfo::kStatusDrew;
2308}
2309
2310/**
2311 * Important note: this method is intended to draw batches of 9-patch objects and
2312 * will not set the scissor enable or dirty the current layer, if any.
2313 * The caller is responsible for properly dirtying the current layer.
2314 */
2315status_t OpenGLRenderer::drawPatches(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
2316        TextureVertex* vertices, uint32_t indexCount, const SkPaint* paint) {
2317    mCaches.activeTexture(0);
2318    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2319    if (!texture) return DrawGlInfo::kStatusDone;
2320    const AutoTexture autoCleanup(texture);
2321
2322    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2323    texture->setFilter(GL_LINEAR, true);
2324
2325    drawIndexedTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, paint,
2326            texture->blend, &vertices[0].x, &vertices[0].u,
2327            GL_TRIANGLES, indexCount, false, true, 0, kModelViewMode_Translate, false);
2328
2329    return DrawGlInfo::kStatusDrew;
2330}
2331
2332status_t OpenGLRenderer::drawVertexBuffer(VertexBufferMode mode,
2333        const VertexBuffer& vertexBuffer, const SkPaint* paint, bool useOffset) {
2334    // not missing call to quickReject/dirtyLayer, always done at a higher level
2335    if (!vertexBuffer.getVertexCount()) {
2336        // no vertices to draw
2337        return DrawGlInfo::kStatusDone;
2338    }
2339
2340    int color = paint->getColor();
2341    bool isAA = paint->isAntiAlias();
2342
2343    setupDraw();
2344    setupDrawNoTexture();
2345    if (isAA) setupDrawAA();
2346    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
2347    setupDrawColorFilter(getColorFilter(paint));
2348    setupDrawShader();
2349    setupDrawBlending(paint, isAA);
2350    setupDrawProgram();
2351    setupDrawModelView(kModelViewMode_Translate, useOffset, 0, 0, 0, 0);
2352    setupDrawColorUniforms();
2353    setupDrawColorFilterUniforms(getColorFilter(paint));
2354    setupDrawShaderUniforms();
2355
2356    const void* vertices = vertexBuffer.getBuffer();
2357    bool force = mCaches.unbindMeshBuffer();
2358    mCaches.bindPositionVertexPointer(true, vertices, isAA ? gAlphaVertexStride : gVertexStride);
2359    mCaches.resetTexCoordsVertexPointer();
2360
2361
2362    int alphaSlot = -1;
2363    if (isAA) {
2364        void* alphaCoords = ((GLbyte*) vertices) + gVertexAlphaOffset;
2365        alphaSlot = mCaches.currentProgram->getAttrib("vtxAlpha");
2366        // TODO: avoid enable/disable in back to back uses of the alpha attribute
2367        glEnableVertexAttribArray(alphaSlot);
2368        glVertexAttribPointer(alphaSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, alphaCoords);
2369    }
2370
2371    if (mode == kVertexBufferMode_Standard) {
2372        mCaches.unbindIndicesBuffer();
2373        glDrawArrays(GL_TRIANGLE_STRIP, 0, vertexBuffer.getVertexCount());
2374    } else if (mode == kVertexBufferMode_OnePolyRingShadow) {
2375        mCaches.bindShadowIndicesBuffer();
2376        glDrawElements(GL_TRIANGLE_STRIP, ONE_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2377    } else if (mode == kVertexBufferMode_TwoPolyRingShadow) {
2378        mCaches.bindShadowIndicesBuffer();
2379        glDrawElements(GL_TRIANGLE_STRIP, TWO_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2380    }
2381
2382    if (isAA) {
2383        glDisableVertexAttribArray(alphaSlot);
2384    }
2385
2386    return DrawGlInfo::kStatusDrew;
2387}
2388
2389/**
2390 * Renders a convex path via tessellation. For AA paths, this function uses a similar approach to
2391 * that of AA lines in the drawLines() function.  We expand the convex path by a half pixel in
2392 * screen space in all directions. However, instead of using a fragment shader to compute the
2393 * translucency of the color from its position, we simply use a varying parameter to define how far
2394 * a given pixel is from the edge. For non-AA paths, the expansion and alpha varying are not used.
2395 *
2396 * Doesn't yet support joins, caps, or path effects.
2397 */
2398status_t OpenGLRenderer::drawConvexPath(const SkPath& path, const SkPaint* paint) {
2399    VertexBuffer vertexBuffer;
2400    // TODO: try clipping large paths to viewport
2401    PathTessellator::tessellatePath(path, paint, *currentTransform(), vertexBuffer);
2402
2403    if (hasLayer()) {
2404        SkRect bounds = path.getBounds();
2405        PathTessellator::expandBoundsForStroke(bounds, paint);
2406        dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, *currentTransform());
2407    }
2408
2409    return drawVertexBuffer(kVertexBufferMode_Standard, vertexBuffer, paint);
2410}
2411
2412/**
2413 * We create tristrips for the lines much like shape stroke tessellation, using a per-vertex alpha
2414 * and additional geometry for defining an alpha slope perimeter.
2415 *
2416 * Using GL_LINES can be difficult because the rasterization rules for those lines produces some
2417 * unexpected results, and may vary between hardware devices. Previously we used a varying-base
2418 * in-shader alpha region, but found it to be taxing on some GPUs.
2419 *
2420 * TODO: try using a fixed input buffer for non-capped lines as in text rendering. this may reduce
2421 * memory transfer by removing need for degenerate vertices.
2422 */
2423status_t OpenGLRenderer::drawLines(const float* points, int count, const SkPaint* paint) {
2424    if (currentSnapshot()->isIgnored() || count < 4) return DrawGlInfo::kStatusDone;
2425
2426    count &= ~0x3; // round down to nearest four
2427
2428    VertexBuffer buffer;
2429    SkRect bounds;
2430    PathTessellator::tessellateLines(points, count, paint, *currentTransform(), bounds, buffer);
2431
2432    // can't pass paint, since style would be checked for outset. outset done by tessellation.
2433    if (quickRejectSetupScissor(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom)) {
2434        return DrawGlInfo::kStatusDone;
2435    }
2436
2437    dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, *currentTransform());
2438
2439    bool useOffset = !paint->isAntiAlias();
2440    return drawVertexBuffer(kVertexBufferMode_Standard, buffer, paint, useOffset);
2441}
2442
2443status_t OpenGLRenderer::drawPoints(const float* points, int count, const SkPaint* paint) {
2444    if (currentSnapshot()->isIgnored() || count < 2) return DrawGlInfo::kStatusDone;
2445
2446    count &= ~0x1; // round down to nearest two
2447
2448    VertexBuffer buffer;
2449    SkRect bounds;
2450    PathTessellator::tessellatePoints(points, count, paint, *currentTransform(), bounds, buffer);
2451
2452    // can't pass paint, since style would be checked for outset. outset done by tessellation.
2453    if (quickRejectSetupScissor(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom)) {
2454        return DrawGlInfo::kStatusDone;
2455    }
2456
2457    dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, *currentTransform());
2458
2459    bool useOffset = !paint->isAntiAlias();
2460    return drawVertexBuffer(kVertexBufferMode_Standard, buffer, paint, useOffset);
2461}
2462
2463status_t OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
2464    // No need to check against the clip, we fill the clip region
2465    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
2466
2467    Rect clip(*currentClipRect());
2468    clip.snapToPixelBoundaries();
2469
2470    SkPaint paint;
2471    paint.setColor(color);
2472    paint.setXfermodeMode(mode);
2473
2474    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, &paint, true);
2475
2476    return DrawGlInfo::kStatusDrew;
2477}
2478
2479status_t OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture,
2480        const SkPaint* paint) {
2481    if (!texture) return DrawGlInfo::kStatusDone;
2482    const AutoTexture autoCleanup(texture);
2483
2484    const float x = left + texture->left - texture->offset;
2485    const float y = top + texture->top - texture->offset;
2486
2487    drawPathTexture(texture, x, y, paint);
2488
2489    return DrawGlInfo::kStatusDrew;
2490}
2491
2492status_t OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
2493        float rx, float ry, const SkPaint* p) {
2494    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2495            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2496        return DrawGlInfo::kStatusDone;
2497    }
2498
2499    if (p->getPathEffect() != 0) {
2500        mCaches.activeTexture(0);
2501        const PathTexture* texture = mCaches.pathCache.getRoundRect(
2502                right - left, bottom - top, rx, ry, p);
2503        return drawShape(left, top, texture, p);
2504    }
2505
2506    SkPath path;
2507    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2508    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2509        float outset = p->getStrokeWidth() / 2;
2510        rect.outset(outset, outset);
2511        rx += outset;
2512        ry += outset;
2513    }
2514    path.addRoundRect(rect, rx, ry);
2515    return drawConvexPath(path, p);
2516}
2517
2518status_t OpenGLRenderer::drawCircle(float x, float y, float radius, const SkPaint* p) {
2519    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(x - radius, y - radius,
2520            x + radius, y + radius, p) ||
2521            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2522        return DrawGlInfo::kStatusDone;
2523    }
2524    if (p->getPathEffect() != 0) {
2525        mCaches.activeTexture(0);
2526        const PathTexture* texture = mCaches.pathCache.getCircle(radius, p);
2527        return drawShape(x - radius, y - radius, texture, p);
2528    }
2529
2530    SkPath path;
2531    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2532        path.addCircle(x, y, radius + p->getStrokeWidth() / 2);
2533    } else {
2534        path.addCircle(x, y, radius);
2535    }
2536    return drawConvexPath(path, p);
2537}
2538
2539status_t OpenGLRenderer::drawOval(float left, float top, float right, float bottom,
2540        const SkPaint* p) {
2541    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2542            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2543        return DrawGlInfo::kStatusDone;
2544    }
2545
2546    if (p->getPathEffect() != 0) {
2547        mCaches.activeTexture(0);
2548        const PathTexture* texture = mCaches.pathCache.getOval(right - left, bottom - top, p);
2549        return drawShape(left, top, texture, p);
2550    }
2551
2552    SkPath path;
2553    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2554    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2555        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2556    }
2557    path.addOval(rect);
2558    return drawConvexPath(path, p);
2559}
2560
2561status_t OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2562        float startAngle, float sweepAngle, bool useCenter, const SkPaint* p) {
2563    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2564            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2565        return DrawGlInfo::kStatusDone;
2566    }
2567
2568    if (fabs(sweepAngle) >= 360.0f) {
2569        return drawOval(left, top, right, bottom, p);
2570    }
2571
2572    // TODO: support fills (accounting for concavity if useCenter && sweepAngle > 180)
2573    if (p->getStyle() != SkPaint::kStroke_Style || p->getPathEffect() != 0 || useCenter) {
2574        mCaches.activeTexture(0);
2575        const PathTexture* texture = mCaches.pathCache.getArc(right - left, bottom - top,
2576                startAngle, sweepAngle, useCenter, p);
2577        return drawShape(left, top, texture, p);
2578    }
2579
2580    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2581    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2582        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2583    }
2584
2585    SkPath path;
2586    if (useCenter) {
2587        path.moveTo(rect.centerX(), rect.centerY());
2588    }
2589    path.arcTo(rect, startAngle, sweepAngle, !useCenter);
2590    if (useCenter) {
2591        path.close();
2592    }
2593    return drawConvexPath(path, p);
2594}
2595
2596// See SkPaintDefaults.h
2597#define SkPaintDefaults_MiterLimit SkIntToScalar(4)
2598
2599status_t OpenGLRenderer::drawRect(float left, float top, float right, float bottom,
2600        const SkPaint* p) {
2601    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2602            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2603        return DrawGlInfo::kStatusDone;
2604    }
2605
2606    if (p->getStyle() != SkPaint::kFill_Style) {
2607        // only fill style is supported by drawConvexPath, since others have to handle joins
2608        if (p->getPathEffect() != 0 || p->getStrokeJoin() != SkPaint::kMiter_Join ||
2609                p->getStrokeMiter() != SkPaintDefaults_MiterLimit) {
2610            mCaches.activeTexture(0);
2611            const PathTexture* texture =
2612                    mCaches.pathCache.getRect(right - left, bottom - top, p);
2613            return drawShape(left, top, texture, p);
2614        }
2615
2616        SkPath path;
2617        SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2618        if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2619            rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2620        }
2621        path.addRect(rect);
2622        return drawConvexPath(path, p);
2623    }
2624
2625    if (p->isAntiAlias() && !currentTransform()->isSimple()) {
2626        SkPath path;
2627        path.addRect(left, top, right, bottom);
2628        return drawConvexPath(path, p);
2629    } else {
2630        drawColorRect(left, top, right, bottom, p);
2631        return DrawGlInfo::kStatusDrew;
2632    }
2633}
2634
2635void OpenGLRenderer::drawTextShadow(const SkPaint* paint, const char* text,
2636        int bytesCount, int count, const float* positions,
2637        FontRenderer& fontRenderer, int alpha, float x, float y) {
2638    mCaches.activeTexture(0);
2639
2640    TextShadow textShadow;
2641    if (!getTextShadow(paint, &textShadow)) {
2642        LOG_ALWAYS_FATAL("failed to query shadow attributes");
2643    }
2644
2645    // NOTE: The drop shadow will not perform gamma correction
2646    //       if shader-based correction is enabled
2647    mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2648    const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2649            paint, text, bytesCount, count, textShadow.radius, positions);
2650    // If the drop shadow exceeds the max texture size or couldn't be
2651    // allocated, skip drawing
2652    if (!shadow) return;
2653    const AutoTexture autoCleanup(shadow);
2654
2655    const float sx = x - shadow->left + textShadow.dx;
2656    const float sy = y - shadow->top + textShadow.dy;
2657
2658    const int shadowAlpha = ((textShadow.color >> 24) & 0xFF) * mSnapshot->alpha;
2659    if (mDrawModifiers.mShader) {
2660        textShadow.color = SK_ColorWHITE;
2661    }
2662
2663    setupDraw();
2664    setupDrawWithTexture(true);
2665    setupDrawAlpha8Color(textShadow.color, shadowAlpha < 255 ? shadowAlpha : alpha);
2666    setupDrawColorFilter(getColorFilter(paint));
2667    setupDrawShader();
2668    setupDrawBlending(paint, true);
2669    setupDrawProgram();
2670    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
2671            sx, sy, sx + shadow->width, sy + shadow->height);
2672    setupDrawTexture(shadow->id);
2673    setupDrawPureColorUniforms();
2674    setupDrawColorFilterUniforms(getColorFilter(paint));
2675    setupDrawShaderUniforms();
2676    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2677
2678    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2679}
2680
2681bool OpenGLRenderer::canSkipText(const SkPaint* paint) const {
2682    float alpha = (hasTextShadow(paint) ? 1.0f : paint->getAlpha()) * mSnapshot->alpha;
2683    return alpha == 0.0f && getXfermode(paint->getXfermode()) == SkXfermode::kSrcOver_Mode;
2684}
2685
2686status_t OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2687        const float* positions, const SkPaint* paint) {
2688    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2689        return DrawGlInfo::kStatusDone;
2690    }
2691
2692    // NOTE: Skia does not support perspective transform on drawPosText yet
2693    if (!currentTransform()->isSimple()) {
2694        return DrawGlInfo::kStatusDone;
2695    }
2696
2697    mCaches.enableScissor();
2698
2699    float x = 0.0f;
2700    float y = 0.0f;
2701    const bool pureTranslate = currentTransform()->isPureTranslate();
2702    if (pureTranslate) {
2703        x = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2704        y = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2705    }
2706
2707    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2708    fontRenderer.setFont(paint, mat4::identity());
2709
2710    int alpha;
2711    SkXfermode::Mode mode;
2712    getAlphaAndMode(paint, &alpha, &mode);
2713
2714    if (CC_UNLIKELY(hasTextShadow(paint))) {
2715        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2716                alpha, 0.0f, 0.0f);
2717    }
2718
2719    // Pick the appropriate texture filtering
2720    bool linearFilter = currentTransform()->changesBounds();
2721    if (pureTranslate && !linearFilter) {
2722        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2723    }
2724    fontRenderer.setTextureFiltering(linearFilter);
2725
2726    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2727    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2728
2729    const bool hasActiveLayer = hasLayer();
2730
2731    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2732    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2733            positions, hasActiveLayer ? &bounds : NULL, &functor)) {
2734        if (hasActiveLayer) {
2735            if (!pureTranslate) {
2736                currentTransform()->mapRect(bounds);
2737            }
2738            dirtyLayerUnchecked(bounds, getRegion());
2739        }
2740    }
2741
2742    return DrawGlInfo::kStatusDrew;
2743}
2744
2745mat4 OpenGLRenderer::findBestFontTransform(const mat4& transform) const {
2746    mat4 fontTransform;
2747    if (CC_LIKELY(transform.isPureTranslate())) {
2748        fontTransform = mat4::identity();
2749    } else {
2750        if (CC_UNLIKELY(transform.isPerspective())) {
2751            fontTransform = mat4::identity();
2752        } else {
2753            float sx, sy;
2754            currentTransform()->decomposeScale(sx, sy);
2755            fontTransform.loadScale(sx, sy, 1.0f);
2756        }
2757    }
2758    return fontTransform;
2759}
2760
2761status_t OpenGLRenderer::drawText(const char* text, int bytesCount, int count, float x, float y,
2762        const float* positions, const SkPaint* paint, float totalAdvance, const Rect& bounds,
2763        DrawOpMode drawOpMode) {
2764
2765    if (drawOpMode == kDrawOpMode_Immediate) {
2766        // The checks for corner-case ignorable text and quick rejection is only done for immediate
2767        // drawing as ops from DeferredDisplayList are already filtered for these
2768        if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint) ||
2769                quickRejectSetupScissor(bounds)) {
2770            return DrawGlInfo::kStatusDone;
2771        }
2772    }
2773
2774    const float oldX = x;
2775    const float oldY = y;
2776
2777    const mat4& transform = *currentTransform();
2778    const bool pureTranslate = transform.isPureTranslate();
2779
2780    if (CC_LIKELY(pureTranslate)) {
2781        x = (int) floorf(x + transform.getTranslateX() + 0.5f);
2782        y = (int) floorf(y + transform.getTranslateY() + 0.5f);
2783    }
2784
2785    int alpha;
2786    SkXfermode::Mode mode;
2787    getAlphaAndMode(paint, &alpha, &mode);
2788
2789    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2790
2791    if (CC_UNLIKELY(hasTextShadow(paint))) {
2792        fontRenderer.setFont(paint, mat4::identity());
2793        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2794                alpha, oldX, oldY);
2795    }
2796
2797    const bool hasActiveLayer = hasLayer();
2798
2799    // We only pass a partial transform to the font renderer. That partial
2800    // matrix defines how glyphs are rasterized. Typically we want glyphs
2801    // to be rasterized at their final size on screen, which means the partial
2802    // matrix needs to take the scale factor into account.
2803    // When a partial matrix is used to transform glyphs during rasterization,
2804    // the mesh is generated with the inverse transform (in the case of scale,
2805    // the mesh is generated at 1.0 / scale for instance.) This allows us to
2806    // apply the full transform matrix at draw time in the vertex shader.
2807    // Applying the full matrix in the shader is the easiest way to handle
2808    // rotation and perspective and allows us to always generated quads in the
2809    // font renderer which greatly simplifies the code, clipping in particular.
2810    mat4 fontTransform = findBestFontTransform(transform);
2811    fontRenderer.setFont(paint, fontTransform);
2812
2813    // Pick the appropriate texture filtering
2814    bool linearFilter = !pureTranslate || fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2815    fontRenderer.setTextureFiltering(linearFilter);
2816
2817    // TODO: Implement better clipping for scaled/rotated text
2818    const Rect* clip = !pureTranslate ? NULL : currentClipRect();
2819    Rect layerBounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2820
2821    bool status;
2822    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2823
2824    // don't call issuedrawcommand, do it at end of batch
2825    bool forceFinish = (drawOpMode != kDrawOpMode_Defer);
2826    if (CC_UNLIKELY(paint->getTextAlign() != SkPaint::kLeft_Align)) {
2827        SkPaint paintCopy(*paint);
2828        paintCopy.setTextAlign(SkPaint::kLeft_Align);
2829        status = fontRenderer.renderPosText(&paintCopy, clip, text, 0, bytesCount, count, x, y,
2830                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2831    } else {
2832        status = fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2833                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2834    }
2835
2836    if ((status || drawOpMode != kDrawOpMode_Immediate) && hasActiveLayer) {
2837        if (!pureTranslate) {
2838            transform.mapRect(layerBounds);
2839        }
2840        dirtyLayerUnchecked(layerBounds, getRegion());
2841    }
2842
2843    drawTextDecorations(totalAdvance, oldX, oldY, paint);
2844
2845    return DrawGlInfo::kStatusDrew;
2846}
2847
2848status_t OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count,
2849        const SkPath* path, float hOffset, float vOffset, const SkPaint* paint) {
2850    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2851        return DrawGlInfo::kStatusDone;
2852    }
2853
2854    // TODO: avoid scissor by calculating maximum bounds using path bounds + font metrics
2855    mCaches.enableScissor();
2856
2857    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2858    fontRenderer.setFont(paint, mat4::identity());
2859    fontRenderer.setTextureFiltering(true);
2860
2861    int alpha;
2862    SkXfermode::Mode mode;
2863    getAlphaAndMode(paint, &alpha, &mode);
2864    TextSetupFunctor functor(this, 0.0f, 0.0f, false, alpha, mode, paint);
2865
2866    const Rect* clip = &mSnapshot->getLocalClip();
2867    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2868
2869    const bool hasActiveLayer = hasLayer();
2870
2871    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2872            hOffset, vOffset, hasActiveLayer ? &bounds : NULL, &functor)) {
2873        if (hasActiveLayer) {
2874            currentTransform()->mapRect(bounds);
2875            dirtyLayerUnchecked(bounds, getRegion());
2876        }
2877    }
2878
2879    return DrawGlInfo::kStatusDrew;
2880}
2881
2882status_t OpenGLRenderer::drawPath(const SkPath* path, const SkPaint* paint) {
2883    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
2884
2885    mCaches.activeTexture(0);
2886
2887    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2888    if (!texture) return DrawGlInfo::kStatusDone;
2889    const AutoTexture autoCleanup(texture);
2890
2891    const float x = texture->left - texture->offset;
2892    const float y = texture->top - texture->offset;
2893
2894    drawPathTexture(texture, x, y, paint);
2895
2896    return DrawGlInfo::kStatusDrew;
2897}
2898
2899status_t OpenGLRenderer::drawLayer(Layer* layer, float x, float y) {
2900    if (!layer) {
2901        return DrawGlInfo::kStatusDone;
2902    }
2903
2904    mat4* transform = NULL;
2905    if (layer->isTextureLayer()) {
2906        transform = &layer->getTransform();
2907        if (!transform->isIdentity()) {
2908            save(SkCanvas::kMatrix_SaveFlag);
2909            concatMatrix(*transform);
2910        }
2911    }
2912
2913    bool clipRequired = false;
2914    const bool rejected = calculateQuickRejectForScissor(x, y,
2915            x + layer->layer.getWidth(), y + layer->layer.getHeight(), &clipRequired, false);
2916
2917    if (rejected) {
2918        if (transform && !transform->isIdentity()) {
2919            restore();
2920        }
2921        return DrawGlInfo::kStatusDone;
2922    }
2923
2924    updateLayer(layer, true);
2925
2926    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
2927    mCaches.activeTexture(0);
2928
2929    if (CC_LIKELY(!layer->region.isEmpty())) {
2930        if (layer->region.isRect()) {
2931            DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
2932                    composeLayerRect(layer, layer->regionRect));
2933        } else if (layer->mesh) {
2934
2935            const float a = getLayerAlpha(layer);
2936            setupDraw();
2937            setupDrawWithTexture();
2938            setupDrawColor(a, a, a, a);
2939            setupDrawColorFilter(layer->getColorFilter());
2940            setupDrawBlending(layer);
2941            setupDrawProgram();
2942            setupDrawPureColorUniforms();
2943            setupDrawColorFilterUniforms(layer->getColorFilter());
2944            setupDrawTexture(layer->getTexture());
2945            if (CC_LIKELY(currentTransform()->isPureTranslate())) {
2946                int tx = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2947                int ty = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2948
2949                layer->setFilter(GL_NEAREST);
2950                setupDrawModelView(kModelViewMode_Translate, false, tx, ty,
2951                        tx + layer->layer.getWidth(), ty + layer->layer.getHeight(), true);
2952            } else {
2953                layer->setFilter(GL_LINEAR);
2954                setupDrawModelView(kModelViewMode_Translate, false, x, y,
2955                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
2956            }
2957
2958            TextureVertex* mesh = &layer->mesh[0];
2959            GLsizei elementsCount = layer->meshElementCount;
2960
2961            while (elementsCount > 0) {
2962                GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
2963
2964                setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
2965                DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
2966                        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL));
2967
2968                elementsCount -= drawCount;
2969                // Though there are 4 vertices in a quad, we use 6 indices per
2970                // quad to draw with GL_TRIANGLES
2971                mesh += (drawCount / 6) * 4;
2972            }
2973
2974#if DEBUG_LAYERS_AS_REGIONS
2975            drawRegionRectsDebug(layer->region);
2976#endif
2977        }
2978
2979        if (layer->debugDrawUpdate) {
2980            layer->debugDrawUpdate = false;
2981
2982            SkPaint paint;
2983            paint.setColor(0x7f00ff00);
2984            drawColorRect(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight(), &paint);
2985        }
2986    }
2987    layer->hasDrawnSinceUpdate = true;
2988
2989    if (transform && !transform->isIdentity()) {
2990        restore();
2991    }
2992
2993    return DrawGlInfo::kStatusDrew;
2994}
2995
2996///////////////////////////////////////////////////////////////////////////////
2997// Shaders
2998///////////////////////////////////////////////////////////////////////////////
2999
3000void OpenGLRenderer::resetShader() {
3001    mDrawModifiers.mShader = NULL;
3002}
3003
3004void OpenGLRenderer::setupShader(SkiaShader* shader) {
3005    mDrawModifiers.mShader = shader;
3006    if (mDrawModifiers.mShader) {
3007        mDrawModifiers.mShader->setCaches(mCaches);
3008    }
3009}
3010
3011///////////////////////////////////////////////////////////////////////////////
3012// Draw filters
3013///////////////////////////////////////////////////////////////////////////////
3014
3015void OpenGLRenderer::resetPaintFilter() {
3016    // when clearing the PaintFilter, the masks should also be cleared for simple DrawModifier
3017    // comparison, see MergingDrawBatch::canMergeWith
3018    mDrawModifiers.mHasDrawFilter = false;
3019    mDrawModifiers.mPaintFilterClearBits = 0;
3020    mDrawModifiers.mPaintFilterSetBits = 0;
3021}
3022
3023void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
3024    mDrawModifiers.mHasDrawFilter = true;
3025    mDrawModifiers.mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
3026    mDrawModifiers.mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
3027}
3028
3029const SkPaint* OpenGLRenderer::filterPaint(const SkPaint* paint) {
3030    if (CC_LIKELY(!mDrawModifiers.mHasDrawFilter || !paint)) {
3031        return paint;
3032    }
3033
3034    uint32_t flags = paint->getFlags();
3035
3036    mFilteredPaint = *paint;
3037    mFilteredPaint.setFlags((flags & ~mDrawModifiers.mPaintFilterClearBits) |
3038            mDrawModifiers.mPaintFilterSetBits);
3039
3040    return &mFilteredPaint;
3041}
3042
3043///////////////////////////////////////////////////////////////////////////////
3044// Drawing implementation
3045///////////////////////////////////////////////////////////////////////////////
3046
3047Texture* OpenGLRenderer::getTexture(const SkBitmap* bitmap) {
3048    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
3049    if (!texture) {
3050        return mCaches.textureCache.get(bitmap);
3051    }
3052    return texture;
3053}
3054
3055void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
3056        float x, float y, const SkPaint* paint) {
3057    if (quickRejectSetupScissor(x, y, x + texture->width, y + texture->height)) {
3058        return;
3059    }
3060
3061    int alpha;
3062    SkXfermode::Mode mode;
3063    getAlphaAndMode(paint, &alpha, &mode);
3064
3065    setupDraw();
3066    setupDrawWithTexture(true);
3067    setupDrawAlpha8Color(paint->getColor(), alpha);
3068    setupDrawColorFilter(getColorFilter(paint));
3069    setupDrawShader();
3070    setupDrawBlending(paint, true);
3071    setupDrawProgram();
3072    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3073            x, y, x + texture->width, y + texture->height);
3074    setupDrawTexture(texture->id);
3075    setupDrawPureColorUniforms();
3076    setupDrawColorFilterUniforms(getColorFilter(paint));
3077    setupDrawShaderUniforms();
3078    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
3079
3080    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3081}
3082
3083// Same values used by Skia
3084#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
3085#define kStdUnderline_Offset    (1.0f / 9.0f)
3086#define kStdUnderline_Thickness (1.0f / 18.0f)
3087
3088void OpenGLRenderer::drawTextDecorations(float underlineWidth, float x, float y,
3089        const SkPaint* paint) {
3090    // Handle underline and strike-through
3091    uint32_t flags = paint->getFlags();
3092    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
3093        SkPaint paintCopy(*paint);
3094
3095        if (CC_LIKELY(underlineWidth > 0.0f)) {
3096            const float textSize = paintCopy.getTextSize();
3097            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
3098
3099            const float left = x;
3100            float top = 0.0f;
3101
3102            int linesCount = 0;
3103            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
3104            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
3105
3106            const int pointsCount = 4 * linesCount;
3107            float points[pointsCount];
3108            int currentPoint = 0;
3109
3110            if (flags & SkPaint::kUnderlineText_Flag) {
3111                top = y + textSize * kStdUnderline_Offset;
3112                points[currentPoint++] = left;
3113                points[currentPoint++] = top;
3114                points[currentPoint++] = left + underlineWidth;
3115                points[currentPoint++] = top;
3116            }
3117
3118            if (flags & SkPaint::kStrikeThruText_Flag) {
3119                top = y + textSize * kStdStrikeThru_Offset;
3120                points[currentPoint++] = left;
3121                points[currentPoint++] = top;
3122                points[currentPoint++] = left + underlineWidth;
3123                points[currentPoint++] = top;
3124            }
3125
3126            paintCopy.setStrokeWidth(strokeWidth);
3127
3128            drawLines(&points[0], pointsCount, &paintCopy);
3129        }
3130    }
3131}
3132
3133status_t OpenGLRenderer::drawRects(const float* rects, int count, const SkPaint* paint) {
3134    if (currentSnapshot()->isIgnored()) {
3135        return DrawGlInfo::kStatusDone;
3136    }
3137
3138    return drawColorRects(rects, count, paint, false, true, true);
3139}
3140
3141static void mapPointFakeZ(Vector3& point, const mat4& transformXY, const mat4& transformZ) {
3142    // map z coordinate with true 3d matrix
3143    point.z = transformZ.mapZ(point);
3144
3145    // map x,y coordinates with draw/Skia matrix
3146    transformXY.mapPoint(point.x, point.y);
3147}
3148
3149status_t OpenGLRenderer::drawShadow(const mat4& casterTransformXY, const mat4& casterTransformZ,
3150        float casterAlpha, bool casterUnclipped, const SkPath* casterPerimeter) {
3151    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
3152
3153    // TODO: use quickRejectWithScissor. For now, always force enable scissor.
3154    mCaches.enableScissor();
3155
3156    SkPaint paint;
3157    paint.setAntiAlias(true); // want to use AlphaVertex
3158
3159    // tessellate caster outline into a 2d polygon
3160    Vector<Vertex> casterVertices2d;
3161    const float casterRefinementThresholdSquared = 20.0f; // TODO: experiment with this value
3162    PathTessellator::approximatePathOutlineVertices(*casterPerimeter,
3163            casterRefinementThresholdSquared, casterVertices2d);
3164    if (!ShadowTessellator::isClockwisePath(*casterPerimeter)) {
3165        ShadowTessellator::reverseVertexArray(casterVertices2d.editArray(),
3166                casterVertices2d.size());
3167    }
3168
3169    if (casterVertices2d.size() == 0) {
3170        // empty caster polygon computed from path
3171        return DrawGlInfo::kStatusDone;
3172    }
3173
3174    // map 2d caster poly into 3d
3175    const int casterVertexCount = casterVertices2d.size();
3176    Vector3 casterPolygon[casterVertexCount];
3177    float minZ = FLT_MAX;
3178    float maxZ = -FLT_MAX;
3179    for (int i = 0; i < casterVertexCount; i++) {
3180        const Vertex& point2d = casterVertices2d[i];
3181        casterPolygon[i] = Vector3(point2d.x, point2d.y, 0);
3182        mapPointFakeZ(casterPolygon[i], casterTransformXY, casterTransformZ);
3183        minZ = fmin(minZ, casterPolygon[i].z);
3184        maxZ = fmax(maxZ, casterPolygon[i].z);
3185    }
3186
3187    // map the centroid of the caster into 3d
3188    Vector2 centroid =  ShadowTessellator::centroid2d(
3189            reinterpret_cast<const Vector2*>(casterVertices2d.array()),
3190            casterVertexCount);
3191    Vector3 centroid3d(centroid.x, centroid.y, 0);
3192    mapPointFakeZ(centroid3d, casterTransformXY, casterTransformZ);
3193
3194    // if the caster intersects the z=0 plane, lift it in Z so it doesn't
3195    if (minZ < SHADOW_MIN_CASTER_Z) {
3196        float casterLift = SHADOW_MIN_CASTER_Z - minZ;
3197        for (int i = 0; i < casterVertexCount; i++) {
3198            casterPolygon[i].z += casterLift;
3199        }
3200        centroid3d.z += casterLift;
3201    }
3202
3203    // Check whether we want to draw the shadow at all by checking the caster's
3204    // bounds against clip.
3205    // We only have ortho projection, so we can just ignore the Z in caster for
3206    // simple rejection calculation.
3207    Rect localClip = mSnapshot->getLocalClip();
3208    Rect casterBounds(casterPerimeter->getBounds());
3209    casterTransformXY.mapRect(casterBounds);
3210
3211    bool isCasterOpaque = (casterAlpha == 1.0f) && casterUnclipped;
3212    // draw caster's shadows
3213    if (mCaches.propertyAmbientShadowStrength > 0) {
3214        paint.setARGB(casterAlpha * mCaches.propertyAmbientShadowStrength, 0, 0, 0);
3215        VertexBuffer ambientShadowVertexBuffer;
3216        VertexBufferMode vertexBufferMode = ShadowTessellator::tessellateAmbientShadow(
3217                isCasterOpaque, casterPolygon, casterVertexCount, centroid3d,
3218                casterBounds, localClip, maxZ, ambientShadowVertexBuffer);
3219        drawVertexBuffer(vertexBufferMode, ambientShadowVertexBuffer, &paint);
3220    }
3221
3222    if (mCaches.propertySpotShadowStrength > 0) {
3223        paint.setARGB(casterAlpha * mCaches.propertySpotShadowStrength, 0, 0, 0);
3224        VertexBuffer spotShadowVertexBuffer;
3225        VertexBufferMode vertexBufferMode = ShadowTessellator::tessellateSpotShadow(
3226                isCasterOpaque, casterPolygon, casterVertexCount,
3227                *currentTransform(), getWidth(), getHeight(), casterBounds, localClip,
3228                spotShadowVertexBuffer);
3229        drawVertexBuffer(vertexBufferMode, spotShadowVertexBuffer, &paint);
3230    }
3231
3232    return DrawGlInfo::kStatusDrew;
3233}
3234
3235status_t OpenGLRenderer::drawColorRects(const float* rects, int count, const SkPaint* paint,
3236        bool ignoreTransform, bool dirty, bool clip) {
3237    if (count == 0) {
3238        return DrawGlInfo::kStatusDone;
3239    }
3240
3241    int color = paint->getColor();
3242    // If a shader is set, preserve only the alpha
3243    if (mDrawModifiers.mShader) {
3244        color |= 0x00ffffff;
3245    }
3246
3247    float left = FLT_MAX;
3248    float top = FLT_MAX;
3249    float right = FLT_MIN;
3250    float bottom = FLT_MIN;
3251
3252    Vertex mesh[count];
3253    Vertex* vertex = mesh;
3254
3255    for (int index = 0; index < count; index += 4) {
3256        float l = rects[index + 0];
3257        float t = rects[index + 1];
3258        float r = rects[index + 2];
3259        float b = rects[index + 3];
3260
3261        Vertex::set(vertex++, l, t);
3262        Vertex::set(vertex++, r, t);
3263        Vertex::set(vertex++, l, b);
3264        Vertex::set(vertex++, r, b);
3265
3266        left = fminf(left, l);
3267        top = fminf(top, t);
3268        right = fmaxf(right, r);
3269        bottom = fmaxf(bottom, b);
3270    }
3271
3272    if (clip && quickRejectSetupScissor(left, top, right, bottom)) {
3273        return DrawGlInfo::kStatusDone;
3274    }
3275
3276    setupDraw();
3277    setupDrawNoTexture();
3278    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3279    setupDrawShader();
3280    setupDrawColorFilter(getColorFilter(paint));
3281    setupDrawBlending(paint);
3282    setupDrawProgram();
3283    setupDrawDirtyRegionsDisabled();
3284    setupDrawModelView(kModelViewMode_Translate, false,
3285            0.0f, 0.0f, 0.0f, 0.0f, ignoreTransform);
3286    setupDrawColorUniforms();
3287    setupDrawShaderUniforms();
3288    setupDrawColorFilterUniforms(getColorFilter(paint));
3289
3290    if (dirty && hasLayer()) {
3291        dirtyLayer(left, top, right, bottom, *currentTransform());
3292    }
3293
3294    issueIndexedQuadDraw(&mesh[0], count / 4);
3295
3296    return DrawGlInfo::kStatusDrew;
3297}
3298
3299void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
3300        const SkPaint* paint, bool ignoreTransform) {
3301    int color = paint->getColor();
3302    // If a shader is set, preserve only the alpha
3303    if (mDrawModifiers.mShader) {
3304        color |= 0x00ffffff;
3305    }
3306
3307    setupDraw();
3308    setupDrawNoTexture();
3309    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3310    setupDrawShader();
3311    setupDrawColorFilter(getColorFilter(paint));
3312    setupDrawBlending(paint);
3313    setupDrawProgram();
3314    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3315            left, top, right, bottom, ignoreTransform);
3316    setupDrawColorUniforms();
3317    setupDrawShaderUniforms(ignoreTransform);
3318    setupDrawColorFilterUniforms(getColorFilter(paint));
3319    setupDrawSimpleMesh();
3320
3321    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3322}
3323
3324void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
3325        Texture* texture, const SkPaint* paint) {
3326    texture->setWrap(GL_CLAMP_TO_EDGE, true);
3327
3328    GLvoid* vertices = (GLvoid*) NULL;
3329    GLvoid* texCoords = (GLvoid*) gMeshTextureOffset;
3330
3331    if (texture->uvMapper) {
3332        vertices = &mMeshVertices[0].x;
3333        texCoords = &mMeshVertices[0].u;
3334
3335        Rect uvs(0.0f, 0.0f, 1.0f, 1.0f);
3336        texture->uvMapper->map(uvs);
3337
3338        resetDrawTextureTexCoords(uvs.left, uvs.top, uvs.right, uvs.bottom);
3339    }
3340
3341    if (CC_LIKELY(currentTransform()->isPureTranslate())) {
3342        const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
3343        const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
3344
3345        texture->setFilter(GL_NEAREST, true);
3346        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
3347                paint, texture->blend, vertices, texCoords,
3348                GL_TRIANGLE_STRIP, gMeshCount, false, true);
3349    } else {
3350        texture->setFilter(getFilter(paint), true);
3351        drawTextureMesh(left, top, right, bottom, texture->id, paint,
3352                texture->blend, vertices, texCoords, GL_TRIANGLE_STRIP, gMeshCount);
3353    }
3354
3355    if (texture->uvMapper) {
3356        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
3357    }
3358}
3359
3360void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
3361        GLuint texture, const SkPaint* paint, bool blend,
3362        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3363        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3364        ModelViewMode modelViewMode, bool dirty) {
3365
3366    int a;
3367    SkXfermode::Mode mode;
3368    getAlphaAndMode(paint, &a, &mode);
3369    const float alpha = a / 255.0f;
3370
3371    setupDraw();
3372    setupDrawWithTexture();
3373    setupDrawColor(alpha, alpha, alpha, alpha);
3374    setupDrawColorFilter(getColorFilter(paint));
3375    setupDrawBlending(paint, blend, swapSrcDst);
3376    setupDrawProgram();
3377    if (!dirty) setupDrawDirtyRegionsDisabled();
3378    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3379    setupDrawTexture(texture);
3380    setupDrawPureColorUniforms();
3381    setupDrawColorFilterUniforms(getColorFilter(paint));
3382    setupDrawMesh(vertices, texCoords, vbo);
3383
3384    glDrawArrays(drawMode, 0, elementsCount);
3385}
3386
3387void OpenGLRenderer::drawIndexedTextureMesh(float left, float top, float right, float bottom,
3388        GLuint texture, const SkPaint* paint, bool blend,
3389        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3390        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3391        ModelViewMode modelViewMode, bool dirty) {
3392
3393    int a;
3394    SkXfermode::Mode mode;
3395    getAlphaAndMode(paint, &a, &mode);
3396    const float alpha = a / 255.0f;
3397
3398    setupDraw();
3399    setupDrawWithTexture();
3400    setupDrawColor(alpha, alpha, alpha, alpha);
3401    setupDrawColorFilter(getColorFilter(paint));
3402    setupDrawBlending(paint, blend, swapSrcDst);
3403    setupDrawProgram();
3404    if (!dirty) setupDrawDirtyRegionsDisabled();
3405    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3406    setupDrawTexture(texture);
3407    setupDrawPureColorUniforms();
3408    setupDrawColorFilterUniforms(getColorFilter(paint));
3409    setupDrawMeshIndices(vertices, texCoords, vbo);
3410
3411    glDrawElements(drawMode, elementsCount, GL_UNSIGNED_SHORT, NULL);
3412}
3413
3414void OpenGLRenderer::drawAlpha8TextureMesh(float left, float top, float right, float bottom,
3415        GLuint texture, const SkPaint* paint,
3416        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3417        bool ignoreTransform, ModelViewMode modelViewMode, bool dirty) {
3418
3419    int color = paint != NULL ? paint->getColor() : 0;
3420    int alpha;
3421    SkXfermode::Mode mode;
3422    getAlphaAndMode(paint, &alpha, &mode);
3423
3424    setupDraw();
3425    setupDrawWithTexture(true);
3426    if (paint != NULL) {
3427        setupDrawAlpha8Color(color, alpha);
3428    }
3429    setupDrawColorFilter(getColorFilter(paint));
3430    setupDrawShader();
3431    setupDrawBlending(paint, true);
3432    setupDrawProgram();
3433    if (!dirty) setupDrawDirtyRegionsDisabled();
3434    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3435    setupDrawTexture(texture);
3436    setupDrawPureColorUniforms();
3437    setupDrawColorFilterUniforms(getColorFilter(paint));
3438    setupDrawShaderUniforms(ignoreTransform);
3439    setupDrawMesh(vertices, texCoords);
3440
3441    glDrawArrays(drawMode, 0, elementsCount);
3442}
3443
3444void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
3445        ProgramDescription& description, bool swapSrcDst) {
3446    if (mCountOverdraw) {
3447        if (!mCaches.blend) glEnable(GL_BLEND);
3448        if (mCaches.lastSrcMode != GL_ONE || mCaches.lastDstMode != GL_ONE) {
3449            glBlendFunc(GL_ONE, GL_ONE);
3450        }
3451
3452        mCaches.blend = true;
3453        mCaches.lastSrcMode = GL_ONE;
3454        mCaches.lastDstMode = GL_ONE;
3455
3456        return;
3457    }
3458
3459    blend = blend || mode != SkXfermode::kSrcOver_Mode;
3460
3461    if (blend) {
3462        // These blend modes are not supported by OpenGL directly and have
3463        // to be implemented using shaders. Since the shader will perform
3464        // the blending, turn blending off here
3465        // If the blend mode cannot be implemented using shaders, fall
3466        // back to the default SrcOver blend mode instead
3467        if (CC_UNLIKELY(mode > SkXfermode::kScreen_Mode)) {
3468            if (CC_UNLIKELY(mExtensions.hasFramebufferFetch())) {
3469                description.framebufferMode = mode;
3470                description.swapSrcDst = swapSrcDst;
3471
3472                if (mCaches.blend) {
3473                    glDisable(GL_BLEND);
3474                    mCaches.blend = false;
3475                }
3476
3477                return;
3478            } else {
3479                mode = SkXfermode::kSrcOver_Mode;
3480            }
3481        }
3482
3483        if (!mCaches.blend) {
3484            glEnable(GL_BLEND);
3485        }
3486
3487        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
3488        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
3489
3490        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
3491            glBlendFunc(sourceMode, destMode);
3492            mCaches.lastSrcMode = sourceMode;
3493            mCaches.lastDstMode = destMode;
3494        }
3495    } else if (mCaches.blend) {
3496        glDisable(GL_BLEND);
3497    }
3498    mCaches.blend = blend;
3499}
3500
3501bool OpenGLRenderer::useProgram(Program* program) {
3502    if (!program->isInUse()) {
3503        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
3504        program->use();
3505        mCaches.currentProgram = program;
3506        return false;
3507    }
3508    return true;
3509}
3510
3511void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
3512    TextureVertex* v = &mMeshVertices[0];
3513    TextureVertex::setUV(v++, u1, v1);
3514    TextureVertex::setUV(v++, u2, v1);
3515    TextureVertex::setUV(v++, u1, v2);
3516    TextureVertex::setUV(v++, u2, v2);
3517}
3518
3519void OpenGLRenderer::getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode) const {
3520    getAlphaAndModeDirect(paint, alpha,  mode);
3521    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3522        // if drawing a layer, ignore the paint's alpha
3523        *alpha = mDrawModifiers.mOverrideLayerAlpha * 255;
3524    }
3525    *alpha *= currentSnapshot()->alpha;
3526}
3527
3528float OpenGLRenderer::getLayerAlpha(const Layer* layer) const {
3529    float alpha;
3530    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3531        alpha = mDrawModifiers.mOverrideLayerAlpha;
3532    } else {
3533        alpha = layer->getAlpha() / 255.0f;
3534    }
3535    return alpha * currentSnapshot()->alpha;
3536}
3537
3538}; // namespace uirenderer
3539}; // namespace android
3540