OpenGLRenderer.cpp revision 15a807bb9c98455a175f42389bdc59f46c0bc195 
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 <SkColor.h>
25#include <SkShader.h>
26#include <SkTypeface.h>
27
28#include <utils/Log.h>
29#include <utils/StopWatch.h>
30
31#include <private/hwui/DrawGlInfo.h>
32
33#include <ui/Rect.h>
34
35#include "OpenGLRenderer.h"
36#include "DeferredDisplayList.h"
37#include "DisplayListRenderer.h"
38#include "Fence.h"
39#include "RenderState.h"
40#include "PathTessellator.h"
41#include "Properties.h"
42#include "ShadowTessellator.h"
43#include "SkiaShader.h"
44#include "utils/GLUtils.h"
45#include "Vector.h"
46#include "VertexBuffer.h"
47
48namespace android {
49namespace uirenderer {
50
51///////////////////////////////////////////////////////////////////////////////
52// Defines
53///////////////////////////////////////////////////////////////////////////////
54
55#define RAD_TO_DEG (180.0f / 3.14159265f)
56#define MIN_ANGLE 0.001f
57
58#define ALPHA_THRESHOLD 0
59
60static GLenum getFilter(const SkPaint* paint) {
61    if (!paint || paint->getFilterLevel() != SkPaint::kNone_FilterLevel) {
62        return GL_LINEAR;
63    }
64    return GL_NEAREST;
65}
66
67///////////////////////////////////////////////////////////////////////////////
68// Globals
69///////////////////////////////////////////////////////////////////////////////
70
71/**
72 * Structure mapping Skia xfermodes to OpenGL blending factors.
73 */
74struct Blender {
75    SkXfermode::Mode mode;
76    GLenum src;
77    GLenum dst;
78}; // struct Blender
79
80// In this array, the index of each Blender equals the value of the first
81// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
82static const Blender gBlends[] = {
83    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
84    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
85    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
86    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
87    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
88    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
89    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
90    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
91    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
92    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
93    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
94    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
95    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
96    { SkXfermode::kModulate_Mode, GL_ZERO,                GL_SRC_COLOR },
97    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
98};
99
100// This array contains the swapped version of each SkXfermode. For instance
101// this array's SrcOver blending mode is actually DstOver. You can refer to
102// createLayer() for more information on the purpose of this array.
103static const Blender gBlendsSwap[] = {
104    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
105    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
106    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
107    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
108    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
109    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
110    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
111    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
112    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
113    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
114    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
115    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
116    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
117    { SkXfermode::kModulate_Mode, GL_DST_COLOR,           GL_ZERO },
118    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
119};
120
121///////////////////////////////////////////////////////////////////////////////
122// Functions
123///////////////////////////////////////////////////////////////////////////////
124
125template<typename T>
126static inline T min(T a, T b) {
127    return a < b ? a : b;
128}
129
130///////////////////////////////////////////////////////////////////////////////
131// Constructors/destructor
132///////////////////////////////////////////////////////////////////////////////
133
134OpenGLRenderer::OpenGLRenderer(RenderState& renderState)
135        : mFrameStarted(false)
136        , mCaches(Caches::getInstance())
137        , mExtensions(Extensions::getInstance())
138        , mRenderState(renderState)
139        , mScissorOptimizationDisabled(false)
140        , mCountOverdraw(false)
141        , mLightCenter((Vector3){FLT_MIN, FLT_MIN, FLT_MIN})
142        , mLightRadius(FLT_MIN)
143        , mAmbientShadowAlpha(0)
144        , mSpotShadowAlpha(0) {
145    // *set* draw modifiers to be 0
146    memset(&mDrawModifiers, 0, sizeof(mDrawModifiers));
147    mDrawModifiers.mOverrideLayerAlpha = 1.0f;
148
149    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
150}
151
152OpenGLRenderer::~OpenGLRenderer() {
153    // The context has already been destroyed at this point, do not call
154    // GL APIs. All GL state should be kept in Caches.h
155}
156
157void OpenGLRenderer::initProperties() {
158    char property[PROPERTY_VALUE_MAX];
159    if (property_get(PROPERTY_DISABLE_SCISSOR_OPTIMIZATION, property, "false")) {
160        mScissorOptimizationDisabled = !strcasecmp(property, "true");
161        INIT_LOGD("  Scissor optimization %s",
162                mScissorOptimizationDisabled ? "disabled" : "enabled");
163    } else {
164        INIT_LOGD("  Scissor optimization enabled");
165    }
166}
167
168void OpenGLRenderer::initLight(const Vector3& lightCenter, float lightRadius,
169        uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha) {
170    mLightCenter = lightCenter;
171    mLightRadius = lightRadius;
172    mAmbientShadowAlpha = ambientShadowAlpha;
173    mSpotShadowAlpha = spotShadowAlpha;
174}
175
176///////////////////////////////////////////////////////////////////////////////
177// Setup
178///////////////////////////////////////////////////////////////////////////////
179
180void OpenGLRenderer::onViewportInitialized() {
181    glDisable(GL_DITHER);
182    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
183
184    glEnableVertexAttribArray(Program::kBindingPosition);
185}
186
187void OpenGLRenderer::setupFrameState(float left, float top,
188        float right, float bottom, bool opaque) {
189    mCaches.clearGarbage();
190
191    initializeSaveStack(left, top, right, bottom);
192    mOpaque = opaque;
193    mTilingClip.set(left, top, right, bottom);
194}
195
196status_t OpenGLRenderer::startFrame() {
197    if (mFrameStarted) return DrawGlInfo::kStatusDone;
198    mFrameStarted = true;
199
200    mDirtyClip = true;
201
202    discardFramebuffer(mTilingClip.left, mTilingClip.top, mTilingClip.right, mTilingClip.bottom);
203
204    mRenderState.setViewport(getWidth(), getHeight());
205
206    // Functors break the tiling extension in pretty spectacular ways
207    // This ensures we don't use tiling when a functor is going to be
208    // invoked during the frame
209    mSuppressTiling = mCaches.hasRegisteredFunctors();
210
211    startTilingCurrentClip(true);
212
213    debugOverdraw(true, true);
214
215    return clear(mTilingClip.left, mTilingClip.top,
216            mTilingClip.right, mTilingClip.bottom, mOpaque);
217}
218
219status_t OpenGLRenderer::prepareDirty(float left, float top,
220        float right, float bottom, bool opaque) {
221
222    setupFrameState(left, top, right, bottom, opaque);
223
224    // Layer renderers will start the frame immediately
225    // The framebuffer renderer will first defer the display list
226    // for each layer and wait until the first drawing command
227    // to start the frame
228    if (currentSnapshot()->fbo == 0) {
229        syncState();
230        updateLayers();
231    } else {
232        return startFrame();
233    }
234
235    return DrawGlInfo::kStatusDone;
236}
237
238void OpenGLRenderer::discardFramebuffer(float left, float top, float right, float bottom) {
239    // If we know that we are going to redraw the entire framebuffer,
240    // perform a discard to let the driver know we don't need to preserve
241    // the back buffer for this frame.
242    if (mExtensions.hasDiscardFramebuffer() &&
243            left <= 0.0f && top <= 0.0f && right >= getWidth() && bottom >= getHeight()) {
244        const bool isFbo = getTargetFbo() == 0;
245        const GLenum attachments[] = {
246                isFbo ? (const GLenum) GL_COLOR_EXT : (const GLenum) GL_COLOR_ATTACHMENT0,
247                isFbo ? (const GLenum) GL_STENCIL_EXT : (const GLenum) GL_STENCIL_ATTACHMENT };
248        glDiscardFramebufferEXT(GL_FRAMEBUFFER, 1, attachments);
249    }
250}
251
252status_t OpenGLRenderer::clear(float left, float top, float right, float bottom, bool opaque) {
253    if (!opaque || mCountOverdraw) {
254        mCaches.enableScissor();
255        mCaches.setScissor(left, getViewportHeight() - bottom, right - left, bottom - top);
256        glClear(GL_COLOR_BUFFER_BIT);
257        return DrawGlInfo::kStatusDrew;
258    }
259
260    mCaches.resetScissor();
261    return DrawGlInfo::kStatusDone;
262}
263
264void OpenGLRenderer::syncState() {
265    if (mCaches.blend) {
266        glEnable(GL_BLEND);
267    } else {
268        glDisable(GL_BLEND);
269    }
270}
271
272void OpenGLRenderer::startTilingCurrentClip(bool opaque, bool expand) {
273    if (!mSuppressTiling) {
274        const Snapshot* snapshot = currentSnapshot();
275
276        const Rect* clip = &mTilingClip;
277        if (snapshot->flags & Snapshot::kFlagFboTarget) {
278            clip = &(snapshot->layer->clipRect);
279        }
280
281        startTiling(*clip, getViewportHeight(), opaque, expand);
282    }
283}
284
285void OpenGLRenderer::startTiling(const Rect& clip, int windowHeight, bool opaque, bool expand) {
286    if (!mSuppressTiling) {
287        if(expand) {
288            // Expand the startTiling region by 1
289            int leftNotZero = (clip.left > 0) ? 1 : 0;
290            int topNotZero = (windowHeight - clip.bottom > 0) ? 1 : 0;
291
292            mCaches.startTiling(
293                clip.left - leftNotZero,
294                windowHeight - clip.bottom - topNotZero,
295                clip.right - clip.left + leftNotZero + 1,
296                clip.bottom - clip.top + topNotZero + 1,
297                opaque);
298        } else {
299            mCaches.startTiling(clip.left, windowHeight - clip.bottom,
300                clip.right - clip.left, clip.bottom - clip.top, opaque);
301        }
302    }
303}
304
305void OpenGLRenderer::endTiling() {
306    if (!mSuppressTiling) mCaches.endTiling();
307}
308
309void OpenGLRenderer::finish() {
310    renderOverdraw();
311    endTiling();
312
313    // When finish() is invoked on FBO 0 we've reached the end
314    // of the current frame
315    if (getTargetFbo() == 0) {
316        mCaches.pathCache.trim();
317        mCaches.tessellationCache.trim();
318    }
319
320    if (!suppressErrorChecks()) {
321#if DEBUG_OPENGL
322        GLUtils::dumpGLErrors();
323#endif
324
325#if DEBUG_MEMORY_USAGE
326        mCaches.dumpMemoryUsage();
327#else
328        if (mCaches.getDebugLevel() & kDebugMemory) {
329            mCaches.dumpMemoryUsage();
330        }
331#endif
332    }
333
334    if (mCountOverdraw) {
335        countOverdraw();
336    }
337
338    mFrameStarted = false;
339}
340
341void OpenGLRenderer::resumeAfterLayer() {
342    mRenderState.setViewport(getViewportWidth(), getViewportHeight());
343    mRenderState.bindFramebuffer(currentSnapshot()->fbo);
344    debugOverdraw(true, false);
345
346    mCaches.resetScissor();
347    dirtyClip();
348}
349
350status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
351    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
352
353    Rect clip(*currentClipRect());
354    clip.snapToPixelBoundaries();
355
356    // Since we don't know what the functor will draw, let's dirty
357    // the entire clip region
358    if (hasLayer()) {
359        dirtyLayerUnchecked(clip, getRegion());
360    }
361
362    DrawGlInfo info;
363    info.clipLeft = clip.left;
364    info.clipTop = clip.top;
365    info.clipRight = clip.right;
366    info.clipBottom = clip.bottom;
367    info.isLayer = hasLayer();
368    info.width = getViewportWidth();
369    info.height = getViewportHeight();
370    currentTransform()->copyTo(&info.transform[0]);
371
372    bool prevDirtyClip = mDirtyClip;
373    // setup GL state for functor
374    if (mDirtyClip) {
375        setStencilFromClip(); // can issue draws, so must precede enableScissor()/interrupt()
376    }
377    if (mCaches.enableScissor() || prevDirtyClip) {
378        setScissorFromClip();
379    }
380
381    mRenderState.invokeFunctor(functor, DrawGlInfo::kModeDraw, &info);
382    // Scissor may have been modified, reset dirty clip
383    dirtyClip();
384
385    return DrawGlInfo::kStatusDrew;
386}
387
388///////////////////////////////////////////////////////////////////////////////
389// Debug
390///////////////////////////////////////////////////////////////////////////////
391
392void OpenGLRenderer::eventMark(const char* name) const {
393    mCaches.eventMark(0, name);
394}
395
396void OpenGLRenderer::startMark(const char* name) const {
397    mCaches.startMark(0, name);
398}
399
400void OpenGLRenderer::endMark() const {
401    mCaches.endMark();
402}
403
404void OpenGLRenderer::debugOverdraw(bool enable, bool clear) {
405    mRenderState.debugOverdraw(enable, clear);
406}
407
408void OpenGLRenderer::renderOverdraw() {
409    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
410        const Rect* clip = &mTilingClip;
411
412        mCaches.enableScissor();
413        mCaches.setScissor(clip->left, firstSnapshot()->getViewportHeight() - clip->bottom,
414                clip->right - clip->left, clip->bottom - clip->top);
415
416        // 1x overdraw
417        mCaches.stencil.enableDebugTest(2);
418        drawColor(mCaches.getOverdrawColor(1), SkXfermode::kSrcOver_Mode);
419
420        // 2x overdraw
421        mCaches.stencil.enableDebugTest(3);
422        drawColor(mCaches.getOverdrawColor(2), SkXfermode::kSrcOver_Mode);
423
424        // 3x overdraw
425        mCaches.stencil.enableDebugTest(4);
426        drawColor(mCaches.getOverdrawColor(3), SkXfermode::kSrcOver_Mode);
427
428        // 4x overdraw and higher
429        mCaches.stencil.enableDebugTest(4, true);
430        drawColor(mCaches.getOverdrawColor(4), SkXfermode::kSrcOver_Mode);
431
432        mCaches.stencil.disable();
433    }
434}
435
436void OpenGLRenderer::countOverdraw() {
437    size_t count = getWidth() * getHeight();
438    uint32_t* buffer = new uint32_t[count];
439    glReadPixels(0, 0, getWidth(), getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, &buffer[0]);
440
441    size_t total = 0;
442    for (size_t i = 0; i < count; i++) {
443        total += buffer[i] & 0xff;
444    }
445
446    mOverdraw = total / float(count);
447
448    delete[] buffer;
449}
450
451///////////////////////////////////////////////////////////////////////////////
452// Layers
453///////////////////////////////////////////////////////////////////////////////
454
455bool OpenGLRenderer::updateLayer(Layer* layer, bool inFrame) {
456    if (layer->deferredUpdateScheduled && layer->renderer
457            && layer->renderNode.get() && layer->renderNode->isRenderable()) {
458        ATRACE_CALL();
459
460        Rect& dirty = layer->dirtyRect;
461
462        if (inFrame) {
463            endTiling();
464            debugOverdraw(false, false);
465        }
466
467        if (CC_UNLIKELY(inFrame || mCaches.drawDeferDisabled)) {
468            layer->render();
469        } else {
470            layer->defer();
471        }
472
473        if (inFrame) {
474            resumeAfterLayer();
475            startTilingCurrentClip();
476        }
477
478        layer->debugDrawUpdate = mCaches.debugLayersUpdates;
479        layer->hasDrawnSinceUpdate = false;
480
481        return true;
482    }
483
484    return false;
485}
486
487void OpenGLRenderer::updateLayers() {
488    // If draw deferring is enabled this method will simply defer
489    // the display list of each individual layer. The layers remain
490    // in the layer updates list which will be cleared by flushLayers().
491    int count = mLayerUpdates.size();
492    if (count > 0) {
493        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
494            startMark("Layer Updates");
495        } else {
496            startMark("Defer Layer Updates");
497        }
498
499        // Note: it is very important to update the layers in order
500        for (int i = 0; i < count; i++) {
501            Layer* layer = mLayerUpdates.itemAt(i);
502            updateLayer(layer, false);
503            if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
504                mCaches.resourceCache.decrementRefcount(layer);
505            }
506        }
507
508        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
509            mLayerUpdates.clear();
510            mRenderState.bindFramebuffer(getTargetFbo());
511        }
512        endMark();
513    }
514}
515
516void OpenGLRenderer::flushLayers() {
517    int count = mLayerUpdates.size();
518    if (count > 0) {
519        startMark("Apply Layer Updates");
520        char layerName[12];
521
522        // Note: it is very important to update the layers in order
523        for (int i = 0; i < count; i++) {
524            sprintf(layerName, "Layer #%d", i);
525            startMark(layerName);
526
527            ATRACE_BEGIN("flushLayer");
528            Layer* layer = mLayerUpdates.itemAt(i);
529            layer->flush();
530            ATRACE_END();
531
532            mCaches.resourceCache.decrementRefcount(layer);
533
534            endMark();
535        }
536
537        mLayerUpdates.clear();
538        mRenderState.bindFramebuffer(getTargetFbo());
539
540        endMark();
541    }
542}
543
544void OpenGLRenderer::pushLayerUpdate(Layer* layer) {
545    if (layer) {
546        // Make sure we don't introduce duplicates.
547        // SortedVector would do this automatically but we need to respect
548        // the insertion order. The linear search is not an issue since
549        // this list is usually very short (typically one item, at most a few)
550        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
551            if (mLayerUpdates.itemAt(i) == layer) {
552                return;
553            }
554        }
555        mLayerUpdates.push_back(layer);
556        mCaches.resourceCache.incrementRefcount(layer);
557    }
558}
559
560void OpenGLRenderer::cancelLayerUpdate(Layer* layer) {
561    if (layer) {
562        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
563            if (mLayerUpdates.itemAt(i) == layer) {
564                mLayerUpdates.removeAt(i);
565                mCaches.resourceCache.decrementRefcount(layer);
566                break;
567            }
568        }
569    }
570}
571
572void OpenGLRenderer::clearLayerUpdates() {
573    size_t count = mLayerUpdates.size();
574    if (count > 0) {
575        mCaches.resourceCache.lock();
576        for (size_t i = 0; i < count; i++) {
577            mCaches.resourceCache.decrementRefcountLocked(mLayerUpdates.itemAt(i));
578        }
579        mCaches.resourceCache.unlock();
580        mLayerUpdates.clear();
581    }
582}
583
584void OpenGLRenderer::flushLayerUpdates() {
585    syncState();
586    updateLayers();
587    flushLayers();
588    // Wait for all the layer updates to be executed
589    AutoFence fence;
590}
591
592///////////////////////////////////////////////////////////////////////////////
593// State management
594///////////////////////////////////////////////////////////////////////////////
595
596void OpenGLRenderer::onSnapshotRestored(const Snapshot& removed, const Snapshot& restored) {
597    bool restoreViewport = removed.flags & Snapshot::kFlagIsFboLayer;
598    bool restoreClip = removed.flags & Snapshot::kFlagClipSet;
599    bool restoreLayer = removed.flags & Snapshot::kFlagIsLayer;
600
601    if (restoreViewport) {
602        mRenderState.setViewport(getViewportWidth(), getViewportHeight());
603    }
604
605    if (restoreClip) {
606        dirtyClip();
607    }
608
609    if (restoreLayer) {
610        endMark(); // Savelayer
611        startMark("ComposeLayer");
612        composeLayer(removed, restored);
613        endMark();
614    }
615}
616
617///////////////////////////////////////////////////////////////////////////////
618// Layers
619///////////////////////////////////////////////////////////////////////////////
620
621int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
622        const SkPaint* paint, int flags, const SkPath* convexMask) {
623    const int count = saveSnapshot(flags);
624
625    if (!currentSnapshot()->isIgnored()) {
626        createLayer(left, top, right, bottom, paint, flags, convexMask);
627    }
628
629    return count;
630}
631
632void OpenGLRenderer::calculateLayerBoundsAndClip(Rect& bounds, Rect& clip, bool fboLayer) {
633    const Rect untransformedBounds(bounds);
634
635    currentTransform()->mapRect(bounds);
636
637    // Layers only make sense if they are in the framebuffer's bounds
638    if (bounds.intersect(*currentClipRect())) {
639        // We cannot work with sub-pixels in this case
640        bounds.snapToPixelBoundaries();
641
642        // When the layer is not an FBO, we may use glCopyTexImage so we
643        // need to make sure the layer does not extend outside the bounds
644        // of the framebuffer
645        const Snapshot& previous = *(currentSnapshot()->previous);
646        Rect previousViewport(0, 0, previous.getViewportWidth(), previous.getViewportHeight());
647        if (!bounds.intersect(previousViewport)) {
648            bounds.setEmpty();
649        } else if (fboLayer) {
650            clip.set(bounds);
651            mat4 inverse;
652            inverse.loadInverse(*currentTransform());
653            inverse.mapRect(clip);
654            clip.snapToPixelBoundaries();
655            if (clip.intersect(untransformedBounds)) {
656                clip.translate(-untransformedBounds.left, -untransformedBounds.top);
657                bounds.set(untransformedBounds);
658            } else {
659                clip.setEmpty();
660            }
661        }
662    } else {
663        bounds.setEmpty();
664    }
665}
666
667void OpenGLRenderer::updateSnapshotIgnoreForLayer(const Rect& bounds, const Rect& clip,
668        bool fboLayer, int alpha) {
669    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
670            bounds.getHeight() > mCaches.maxTextureSize ||
671            (fboLayer && clip.isEmpty())) {
672        mSnapshot->empty = fboLayer;
673    } else {
674        mSnapshot->invisible = mSnapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
675    }
676}
677
678int OpenGLRenderer::saveLayerDeferred(float left, float top, float right, float bottom,
679        const SkPaint* paint, int flags) {
680    const int count = saveSnapshot(flags);
681
682    if (!currentSnapshot()->isIgnored() && (flags & SkCanvas::kClipToLayer_SaveFlag)) {
683        // initialize the snapshot as though it almost represents an FBO layer so deferred draw
684        // operations will be able to store and restore the current clip and transform info, and
685        // quick rejection will be correct (for display lists)
686
687        Rect bounds(left, top, right, bottom);
688        Rect clip;
689        calculateLayerBoundsAndClip(bounds, clip, true);
690        updateSnapshotIgnoreForLayer(bounds, clip, true, getAlphaDirect(paint));
691
692        if (!currentSnapshot()->isIgnored()) {
693            mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
694            mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
695            mSnapshot->initializeViewport(bounds.getWidth(), bounds.getHeight());
696            mSnapshot->roundRectClipState = NULL;
697        }
698    }
699
700    return count;
701}
702
703/**
704 * Layers are viewed by Skia are slightly different than layers in image editing
705 * programs (for instance.) When a layer is created, previously created layers
706 * and the frame buffer still receive every drawing command. For instance, if a
707 * layer is created and a shape intersecting the bounds of the layers and the
708 * framebuffer is draw, the shape will be drawn on both (unless the layer was
709 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
710 *
711 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
712 * texture. Unfortunately, this is inefficient as it requires every primitive to
713 * be drawn n + 1 times, where n is the number of active layers. In practice this
714 * means, for every primitive:
715 *   - Switch active frame buffer
716 *   - Change viewport, clip and projection matrix
717 *   - Issue the drawing
718 *
719 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
720 * To avoid this, layers are implemented in a different way here, at least in the
721 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
722 * is set. When this flag is set we can redirect all drawing operations into a
723 * single FBO.
724 *
725 * This implementation relies on the frame buffer being at least RGBA 8888. When
726 * a layer is created, only a texture is created, not an FBO. The content of the
727 * frame buffer contained within the layer's bounds is copied into this texture
728 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
729 * buffer and drawing continues as normal. This technique therefore treats the
730 * frame buffer as a scratch buffer for the layers.
731 *
732 * To compose the layers back onto the frame buffer, each layer texture
733 * (containing the original frame buffer data) is drawn as a simple quad over
734 * the frame buffer. The trick is that the quad is set as the composition
735 * destination in the blending equation, and the frame buffer becomes the source
736 * of the composition.
737 *
738 * Drawing layers with an alpha value requires an extra step before composition.
739 * An empty quad is drawn over the layer's region in the frame buffer. This quad
740 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
741 * quad is used to multiply the colors in the frame buffer. This is achieved by
742 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
743 * GL_ZERO, GL_SRC_ALPHA.
744 *
745 * Because glCopyTexImage2D() can be slow, an alternative implementation might
746 * be use to draw a single clipped layer. The implementation described above
747 * is correct in every case.
748 *
749 * (1) The frame buffer is actually not cleared right away. To allow the GPU
750 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
751 *     buffer is left untouched until the first drawing operation. Only when
752 *     something actually gets drawn are the layers regions cleared.
753 */
754bool OpenGLRenderer::createLayer(float left, float top, float right, float bottom,
755        const SkPaint* paint, int flags, const SkPath* convexMask) {
756    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
757    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
758
759    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
760
761    // Window coordinates of the layer
762    Rect clip;
763    Rect bounds(left, top, right, bottom);
764    calculateLayerBoundsAndClip(bounds, clip, fboLayer);
765    updateSnapshotIgnoreForLayer(bounds, clip, fboLayer, getAlphaDirect(paint));
766
767    // Bail out if we won't draw in this snapshot
768    if (currentSnapshot()->isIgnored()) {
769        return false;
770    }
771
772    mCaches.activeTexture(0);
773    Layer* layer = mCaches.layerCache.get(mRenderState, bounds.getWidth(), bounds.getHeight());
774    if (!layer) {
775        return false;
776    }
777
778    layer->setPaint(paint);
779    layer->layer.set(bounds);
780    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
781            bounds.getWidth() / float(layer->getWidth()), 0.0f);
782
783    layer->setBlend(true);
784    layer->setDirty(false);
785    layer->setConvexMask(convexMask); // note: the mask must be cleared before returning to the cache
786
787    // Save the layer in the snapshot
788    mSnapshot->flags |= Snapshot::kFlagIsLayer;
789    mSnapshot->layer = layer;
790
791    startMark("SaveLayer");
792    if (fboLayer) {
793        return createFboLayer(layer, bounds, clip);
794    } else {
795        // Copy the framebuffer into the layer
796        layer->bindTexture();
797        if (!bounds.isEmpty()) {
798            if (layer->isEmpty()) {
799                // Workaround for some GL drivers. When reading pixels lying outside
800                // of the window we should get undefined values for those pixels.
801                // Unfortunately some drivers will turn the entire target texture black
802                // when reading outside of the window.
803                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->getWidth(), layer->getHeight(),
804                        0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
805                layer->setEmpty(false);
806            }
807
808            glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
809                    bounds.left, getViewportHeight() - bounds.bottom,
810                    bounds.getWidth(), bounds.getHeight());
811
812            // Enqueue the buffer coordinates to clear the corresponding region later
813            mLayers.push(new Rect(bounds));
814        }
815    }
816
817    return true;
818}
819
820bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, Rect& clip) {
821    layer->clipRect.set(clip);
822    layer->setFbo(mCaches.fboCache.get());
823
824    mSnapshot->region = &mSnapshot->layer->region;
825    mSnapshot->flags |= Snapshot::kFlagFboTarget | Snapshot::kFlagIsFboLayer;
826    mSnapshot->fbo = layer->getFbo();
827    mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
828    mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
829    mSnapshot->initializeViewport(bounds.getWidth(), bounds.getHeight());
830    mSnapshot->roundRectClipState = NULL;
831
832    endTiling();
833    debugOverdraw(false, false);
834    // Bind texture to FBO
835    mRenderState.bindFramebuffer(layer->getFbo());
836    layer->bindTexture();
837
838    // Initialize the texture if needed
839    if (layer->isEmpty()) {
840        layer->allocateTexture();
841        layer->setEmpty(false);
842    }
843
844    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
845            layer->getTexture(), 0);
846
847    // Expand the startTiling region by 1
848    startTilingCurrentClip(true, true);
849
850    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
851    mCaches.enableScissor();
852    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
853            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
854    glClear(GL_COLOR_BUFFER_BIT);
855
856    dirtyClip();
857
858    // Change the ortho projection
859    mRenderState.setViewport(bounds.getWidth(), bounds.getHeight());
860    return true;
861}
862
863/**
864 * Read the documentation of createLayer() before doing anything in this method.
865 */
866void OpenGLRenderer::composeLayer(const Snapshot& removed, const Snapshot& restored) {
867    if (!removed.layer) {
868        ALOGE("Attempting to compose a layer that does not exist");
869        return;
870    }
871
872    Layer* layer = removed.layer;
873    const Rect& rect = layer->layer;
874    const bool fboLayer = removed.flags & Snapshot::kFlagIsFboLayer;
875
876    bool clipRequired = false;
877    calculateQuickRejectForScissor(rect.left, rect.top, rect.right, rect.bottom,
878            &clipRequired, NULL, false); // safely ignore return, should never be rejected
879    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
880
881    if (fboLayer) {
882        endTiling();
883
884        // Detach the texture from the FBO
885        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
886
887        layer->removeFbo(false);
888
889        // Unbind current FBO and restore previous one
890        mRenderState.bindFramebuffer(restored.fbo);
891        debugOverdraw(true, false);
892
893        startTilingCurrentClip();
894    }
895
896    if (!fboLayer && layer->getAlpha() < 255) {
897        SkPaint layerPaint;
898        layerPaint.setAlpha(layer->getAlpha());
899        layerPaint.setXfermodeMode(SkXfermode::kDstIn_Mode);
900        layerPaint.setColorFilter(layer->getColorFilter());
901
902        drawColorRect(rect.left, rect.top, rect.right, rect.bottom, &layerPaint, true);
903        // Required below, composeLayerRect() will divide by 255
904        layer->setAlpha(255);
905    }
906
907    mCaches.unbindMeshBuffer();
908
909    mCaches.activeTexture(0);
910
911    // When the layer is stored in an FBO, we can save a bit of fillrate by
912    // drawing only the dirty region
913    if (fboLayer) {
914        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *restored.transform);
915        composeLayerRegion(layer, rect);
916    } else if (!rect.isEmpty()) {
917        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
918
919        save(0);
920        // the layer contains screen buffer content that shouldn't be alpha modulated
921        // (and any necessary alpha modulation was handled drawing into the layer)
922        mSnapshot->alpha = 1.0f;
923        composeLayerRect(layer, rect, true);
924        restore();
925    }
926
927    dirtyClip();
928
929    // Failing to add the layer to the cache should happen only if the layer is too large
930    layer->setConvexMask(NULL);
931    if (!mCaches.layerCache.put(layer)) {
932        LAYER_LOGD("Deleting layer");
933        Caches::getInstance().resourceCache.decrementRefcount(layer);
934    }
935}
936
937void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
938    float alpha = getLayerAlpha(layer);
939
940    setupDraw();
941    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
942        setupDrawWithTexture();
943    } else {
944        setupDrawWithExternalTexture();
945    }
946    setupDrawTextureTransform();
947    setupDrawColor(alpha, alpha, alpha, alpha);
948    setupDrawColorFilter(layer->getColorFilter());
949    setupDrawBlending(layer);
950    setupDrawProgram();
951    setupDrawPureColorUniforms();
952    setupDrawColorFilterUniforms(layer->getColorFilter());
953    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
954        setupDrawTexture(layer->getTexture());
955    } else {
956        setupDrawExternalTexture(layer->getTexture());
957    }
958    if (currentTransform()->isPureTranslate() &&
959            !layer->getForceFilter() &&
960            layer->getWidth() == (uint32_t) rect.getWidth() &&
961            layer->getHeight() == (uint32_t) rect.getHeight()) {
962        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
963        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
964
965        layer->setFilter(GL_NEAREST);
966        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
967                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
968    } else {
969        layer->setFilter(GL_LINEAR);
970        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
971                rect.left, rect.top, rect.right, rect.bottom);
972    }
973    setupDrawTextureTransformUniforms(layer->getTexTransform());
974    setupDrawMesh(&mMeshVertices[0].x, &mMeshVertices[0].u);
975
976    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
977}
978
979void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
980    if (!layer->isTextureLayer()) {
981        const Rect& texCoords = layer->texCoords;
982        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
983                texCoords.right, texCoords.bottom);
984
985        float x = rect.left;
986        float y = rect.top;
987        bool simpleTransform = currentTransform()->isPureTranslate() &&
988                layer->getWidth() == (uint32_t) rect.getWidth() &&
989                layer->getHeight() == (uint32_t) rect.getHeight();
990
991        if (simpleTransform) {
992            // When we're swapping, the layer is already in screen coordinates
993            if (!swap) {
994                x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
995                y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
996            }
997
998            layer->setFilter(GL_NEAREST, true);
999        } else {
1000            layer->setFilter(GL_LINEAR, true);
1001        }
1002
1003        SkPaint layerPaint;
1004        layerPaint.setAlpha(getLayerAlpha(layer) * 255);
1005        layerPaint.setXfermodeMode(layer->getMode());
1006        layerPaint.setColorFilter(layer->getColorFilter());
1007
1008        bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f;
1009        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
1010                layer->getTexture(), &layerPaint, blend,
1011                &mMeshVertices[0].x, &mMeshVertices[0].u,
1012                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
1013
1014        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1015    } else {
1016        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
1017        drawTextureLayer(layer, rect);
1018        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1019    }
1020}
1021
1022/**
1023 * Issues the command X, and if we're composing a save layer to the fbo or drawing a newly updated
1024 * hardware layer with overdraw debug on, draws again to the stencil only, so that these draw
1025 * operations are correctly counted twice for overdraw. NOTE: assumes composeLayerRegion only used
1026 * by saveLayer's restore
1027 */
1028#define DRAW_DOUBLE_STENCIL_IF(COND, DRAW_COMMAND) {                             \
1029        DRAW_COMMAND;                                                            \
1030        if (CC_UNLIKELY(mCaches.debugOverdraw && getTargetFbo() == 0 && COND)) { \
1031            glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);                 \
1032            DRAW_COMMAND;                                                        \
1033            glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);                     \
1034        }                                                                        \
1035    }
1036
1037#define DRAW_DOUBLE_STENCIL(DRAW_COMMAND) DRAW_DOUBLE_STENCIL_IF(true, DRAW_COMMAND)
1038
1039// This class is purely for inspection. It inherits from SkShader, but Skia does not know how to
1040// use it. The OpenGLRenderer will look at it to find its Layer and whether it is opaque.
1041class LayerShader : public SkShader {
1042public:
1043    LayerShader(Layer* layer, const SkMatrix* localMatrix)
1044    : INHERITED(localMatrix)
1045    , mLayer(layer) {
1046    }
1047
1048    virtual bool asACustomShader(void** data) const {
1049        if (data) {
1050            *data = static_cast<void*>(mLayer);
1051        }
1052        return true;
1053    }
1054
1055    virtual bool isOpaque() const {
1056        return !mLayer->isBlend();
1057    }
1058
1059protected:
1060    virtual void shadeSpan(int x, int y, SkPMColor[], int count) {
1061        LOG_ALWAYS_FATAL("LayerShader should never be drawn with raster backend.");
1062    }
1063
1064    virtual void flatten(SkWriteBuffer&) const {
1065        LOG_ALWAYS_FATAL("LayerShader should never be flattened.");
1066    }
1067
1068    virtual Factory getFactory() const {
1069        LOG_ALWAYS_FATAL("LayerShader should never be created from a stream.");
1070        return NULL;
1071    }
1072private:
1073    // Unowned.
1074    Layer* mLayer;
1075    typedef SkShader INHERITED;
1076};
1077
1078void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
1079    if (CC_UNLIKELY(layer->region.isEmpty())) return; // nothing to draw
1080
1081    if (layer->getConvexMask()) {
1082        save(SkCanvas::kClip_SaveFlag | SkCanvas::kMatrix_SaveFlag);
1083
1084        // clip to the area of the layer the mask can be larger
1085        clipRect(rect.left, rect.top, rect.right, rect.bottom, SkRegion::kIntersect_Op);
1086
1087        SkPaint paint;
1088        paint.setAntiAlias(true);
1089        paint.setColor(SkColorSetARGB(int(getLayerAlpha(layer) * 255), 0, 0, 0));
1090
1091        // create LayerShader to map SaveLayer content into subsequent draw
1092        SkMatrix shaderMatrix;
1093        shaderMatrix.setTranslate(rect.left, rect.bottom);
1094        shaderMatrix.preScale(1, -1);
1095        LayerShader layerShader(layer, &shaderMatrix);
1096        paint.setShader(&layerShader);
1097
1098        // Since the drawing primitive is defined in local drawing space,
1099        // we don't need to modify the draw matrix
1100        const SkPath* maskPath = layer->getConvexMask();
1101        DRAW_DOUBLE_STENCIL(drawConvexPath(*maskPath, &paint));
1102
1103        paint.setShader(NULL);
1104        restore();
1105
1106        return;
1107    }
1108
1109    if (layer->region.isRect()) {
1110        layer->setRegionAsRect();
1111
1112        DRAW_DOUBLE_STENCIL(composeLayerRect(layer, layer->regionRect));
1113
1114        layer->region.clear();
1115        return;
1116    }
1117
1118    // standard Region based draw
1119    size_t count;
1120    const android::Rect* rects;
1121    Region safeRegion;
1122    if (CC_LIKELY(hasRectToRectTransform())) {
1123        rects = layer->region.getArray(&count);
1124    } else {
1125        safeRegion = Region::createTJunctionFreeRegion(layer->region);
1126        rects = safeRegion.getArray(&count);
1127    }
1128
1129    const float alpha = getLayerAlpha(layer);
1130    const float texX = 1.0f / float(layer->getWidth());
1131    const float texY = 1.0f / float(layer->getHeight());
1132    const float height = rect.getHeight();
1133
1134    setupDraw();
1135
1136    // We must get (and therefore bind) the region mesh buffer
1137    // after we setup drawing in case we need to mess with the
1138    // stencil buffer in setupDraw()
1139    TextureVertex* mesh = mCaches.getRegionMesh();
1140    uint32_t numQuads = 0;
1141
1142    setupDrawWithTexture();
1143    setupDrawColor(alpha, alpha, alpha, alpha);
1144    setupDrawColorFilter(layer->getColorFilter());
1145    setupDrawBlending(layer);
1146    setupDrawProgram();
1147    setupDrawDirtyRegionsDisabled();
1148    setupDrawPureColorUniforms();
1149    setupDrawColorFilterUniforms(layer->getColorFilter());
1150    setupDrawTexture(layer->getTexture());
1151    if (currentTransform()->isPureTranslate()) {
1152        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
1153        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
1154
1155        layer->setFilter(GL_NEAREST);
1156        setupDrawModelView(kModelViewMode_Translate, false,
1157                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1158    } else {
1159        layer->setFilter(GL_LINEAR);
1160        setupDrawModelView(kModelViewMode_Translate, false,
1161                rect.left, rect.top, rect.right, rect.bottom);
1162    }
1163    setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
1164
1165    for (size_t i = 0; i < count; i++) {
1166        const android::Rect* r = &rects[i];
1167
1168        const float u1 = r->left * texX;
1169        const float v1 = (height - r->top) * texY;
1170        const float u2 = r->right * texX;
1171        const float v2 = (height - r->bottom) * texY;
1172
1173        // TODO: Reject quads outside of the clip
1174        TextureVertex::set(mesh++, r->left, r->top, u1, v1);
1175        TextureVertex::set(mesh++, r->right, r->top, u2, v1);
1176        TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
1177        TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
1178
1179        numQuads++;
1180
1181        if (numQuads >= gMaxNumberOfQuads) {
1182            DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1183                            GL_UNSIGNED_SHORT, NULL));
1184            numQuads = 0;
1185            mesh = mCaches.getRegionMesh();
1186        }
1187    }
1188
1189    if (numQuads > 0) {
1190        DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1191                        GL_UNSIGNED_SHORT, NULL));
1192    }
1193
1194#if DEBUG_LAYERS_AS_REGIONS
1195    drawRegionRectsDebug(layer->region);
1196#endif
1197
1198    layer->region.clear();
1199}
1200
1201#if DEBUG_LAYERS_AS_REGIONS
1202void OpenGLRenderer::drawRegionRectsDebug(const Region& region) {
1203    size_t count;
1204    const android::Rect* rects = region.getArray(&count);
1205
1206    uint32_t colors[] = {
1207            0x7fff0000, 0x7f00ff00,
1208            0x7f0000ff, 0x7fff00ff,
1209    };
1210
1211    int offset = 0;
1212    int32_t top = rects[0].top;
1213
1214    for (size_t i = 0; i < count; i++) {
1215        if (top != rects[i].top) {
1216            offset ^= 0x2;
1217            top = rects[i].top;
1218        }
1219
1220        SkPaint paint;
1221        paint.setColor(colors[offset + (i & 0x1)]);
1222        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
1223        drawColorRect(r.left, r.top, r.right, r.bottom, paint);
1224    }
1225}
1226#endif
1227
1228void OpenGLRenderer::drawRegionRects(const SkRegion& region, const SkPaint& paint, bool dirty) {
1229    Vector<float> rects;
1230
1231    SkRegion::Iterator it(region);
1232    while (!it.done()) {
1233        const SkIRect& r = it.rect();
1234        rects.push(r.fLeft);
1235        rects.push(r.fTop);
1236        rects.push(r.fRight);
1237        rects.push(r.fBottom);
1238        it.next();
1239    }
1240
1241    drawColorRects(rects.array(), rects.size(), &paint, true, dirty, false);
1242}
1243
1244void OpenGLRenderer::dirtyLayer(const float left, const float top,
1245        const float right, const float bottom, const mat4 transform) {
1246    if (hasLayer()) {
1247        Rect bounds(left, top, right, bottom);
1248        transform.mapRect(bounds);
1249        dirtyLayerUnchecked(bounds, getRegion());
1250    }
1251}
1252
1253void OpenGLRenderer::dirtyLayer(const float left, const float top,
1254        const float right, const float bottom) {
1255    if (hasLayer()) {
1256        Rect bounds(left, top, right, bottom);
1257        dirtyLayerUnchecked(bounds, getRegion());
1258    }
1259}
1260
1261void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
1262    if (bounds.intersect(*currentClipRect())) {
1263        bounds.snapToPixelBoundaries();
1264        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1265        if (!dirty.isEmpty()) {
1266            region->orSelf(dirty);
1267        }
1268    }
1269}
1270
1271void OpenGLRenderer::issueIndexedQuadDraw(Vertex* mesh, GLsizei quadsCount) {
1272    GLsizei elementsCount = quadsCount * 6;
1273    while (elementsCount > 0) {
1274        GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
1275
1276        setupDrawIndexedVertices(&mesh[0].x);
1277        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL);
1278
1279        elementsCount -= drawCount;
1280        // Though there are 4 vertices in a quad, we use 6 indices per
1281        // quad to draw with GL_TRIANGLES
1282        mesh += (drawCount / 6) * 4;
1283    }
1284}
1285
1286void OpenGLRenderer::clearLayerRegions() {
1287    const size_t count = mLayers.size();
1288    if (count == 0) return;
1289
1290    if (!currentSnapshot()->isIgnored()) {
1291        // Doing several glScissor/glClear here can negatively impact
1292        // GPUs with a tiler architecture, instead we draw quads with
1293        // the Clear blending mode
1294
1295        // The list contains bounds that have already been clipped
1296        // against their initial clip rect, and the current clip
1297        // is likely different so we need to disable clipping here
1298        bool scissorChanged = mCaches.disableScissor();
1299
1300        Vertex mesh[count * 4];
1301        Vertex* vertex = mesh;
1302
1303        for (uint32_t i = 0; i < count; i++) {
1304            Rect* bounds = mLayers.itemAt(i);
1305
1306            Vertex::set(vertex++, bounds->left, bounds->top);
1307            Vertex::set(vertex++, bounds->right, bounds->top);
1308            Vertex::set(vertex++, bounds->left, bounds->bottom);
1309            Vertex::set(vertex++, bounds->right, bounds->bottom);
1310
1311            delete bounds;
1312        }
1313        // We must clear the list of dirty rects before we
1314        // call setupDraw() to prevent stencil setup to do
1315        // the same thing again
1316        mLayers.clear();
1317
1318        SkPaint clearPaint;
1319        clearPaint.setXfermodeMode(SkXfermode::kClear_Mode);
1320
1321        setupDraw(false);
1322        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
1323        setupDrawBlending(&clearPaint, true);
1324        setupDrawProgram();
1325        setupDrawPureColorUniforms();
1326        setupDrawModelView(kModelViewMode_Translate, false,
1327                0.0f, 0.0f, 0.0f, 0.0f, true);
1328
1329        issueIndexedQuadDraw(&mesh[0], count);
1330
1331        if (scissorChanged) mCaches.enableScissor();
1332    } else {
1333        for (uint32_t i = 0; i < count; i++) {
1334            delete mLayers.itemAt(i);
1335        }
1336        mLayers.clear();
1337    }
1338}
1339
1340///////////////////////////////////////////////////////////////////////////////
1341// State Deferral
1342///////////////////////////////////////////////////////////////////////////////
1343
1344bool OpenGLRenderer::storeDisplayState(DeferredDisplayState& state, int stateDeferFlags) {
1345    const Rect* currentClip = currentClipRect();
1346    const mat4* currentMatrix = currentTransform();
1347
1348    if (stateDeferFlags & kStateDeferFlag_Draw) {
1349        // state has bounds initialized in local coordinates
1350        if (!state.mBounds.isEmpty()) {
1351            currentMatrix->mapRect(state.mBounds);
1352            Rect clippedBounds(state.mBounds);
1353            // NOTE: if we ever want to use this clipping info to drive whether the scissor
1354            // is used, it should more closely duplicate the quickReject logic (in how it uses
1355            // snapToPixelBoundaries)
1356
1357            if(!clippedBounds.intersect(*currentClip)) {
1358                // quick rejected
1359                return true;
1360            }
1361
1362            state.mClipSideFlags = kClipSide_None;
1363            if (!currentClip->contains(state.mBounds)) {
1364                int& flags = state.mClipSideFlags;
1365                // op partially clipped, so record which sides are clipped for clip-aware merging
1366                if (currentClip->left > state.mBounds.left) flags |= kClipSide_Left;
1367                if (currentClip->top > state.mBounds.top) flags |= kClipSide_Top;
1368                if (currentClip->right < state.mBounds.right) flags |= kClipSide_Right;
1369                if (currentClip->bottom < state.mBounds.bottom) flags |= kClipSide_Bottom;
1370            }
1371            state.mBounds.set(clippedBounds);
1372        } else {
1373            // Empty bounds implies size unknown. Label op as conservatively clipped to disable
1374            // overdraw avoidance (since we don't know what it overlaps)
1375            state.mClipSideFlags = kClipSide_ConservativeFull;
1376            state.mBounds.set(*currentClip);
1377        }
1378    }
1379
1380    state.mClipValid = (stateDeferFlags & kStateDeferFlag_Clip);
1381    if (state.mClipValid) {
1382        state.mClip.set(*currentClip);
1383    }
1384
1385    // Transform, drawModifiers, and alpha always deferred, since they are used by state operations
1386    // (Note: saveLayer/restore use colorFilter and alpha, so we just save restore everything)
1387    state.mMatrix.load(*currentMatrix);
1388    state.mDrawModifiers = mDrawModifiers;
1389    state.mAlpha = currentSnapshot()->alpha;
1390
1391    // always store/restore, since it's just a pointer
1392    state.mRoundRectClipState = currentSnapshot()->roundRectClipState;
1393    return false;
1394}
1395
1396void OpenGLRenderer::restoreDisplayState(const DeferredDisplayState& state, bool skipClipRestore) {
1397    setMatrix(state.mMatrix);
1398    mSnapshot->alpha = state.mAlpha;
1399    mDrawModifiers = state.mDrawModifiers;
1400    mSnapshot->roundRectClipState = state.mRoundRectClipState;
1401
1402    if (state.mClipValid && !skipClipRestore) {
1403        mSnapshot->setClip(state.mClip.left, state.mClip.top,
1404                state.mClip.right, state.mClip.bottom);
1405        dirtyClip();
1406    }
1407}
1408
1409/**
1410 * Merged multidraw (such as in drawText and drawBitmaps rely on the fact that no clipping is done
1411 * in the draw path. Instead, clipping is done ahead of time - either as a single clip rect (when at
1412 * least one op is clipped), or disabled entirely (because no merged op is clipped)
1413 *
1414 * This method should be called when restoreDisplayState() won't be restoring the clip
1415 */
1416void OpenGLRenderer::setupMergedMultiDraw(const Rect* clipRect) {
1417    if (clipRect != NULL) {
1418        mSnapshot->setClip(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
1419    } else {
1420        mSnapshot->setClip(0, 0, getWidth(), getHeight());
1421    }
1422    dirtyClip();
1423    mCaches.setScissorEnabled(clipRect != NULL || mScissorOptimizationDisabled);
1424}
1425
1426///////////////////////////////////////////////////////////////////////////////
1427// Clipping
1428///////////////////////////////////////////////////////////////////////////////
1429
1430void OpenGLRenderer::setScissorFromClip() {
1431    Rect clip(*currentClipRect());
1432    clip.snapToPixelBoundaries();
1433
1434    if (mCaches.setScissor(clip.left, getViewportHeight() - clip.bottom,
1435            clip.getWidth(), clip.getHeight())) {
1436        mDirtyClip = false;
1437    }
1438}
1439
1440void OpenGLRenderer::ensureStencilBuffer() {
1441    // Thanks to the mismatch between EGL and OpenGL ES FBO we
1442    // cannot attach a stencil buffer to fbo0 dynamically. Let's
1443    // just hope we have one when hasLayer() returns false.
1444    if (hasLayer()) {
1445        attachStencilBufferToLayer(currentSnapshot()->layer);
1446    }
1447}
1448
1449void OpenGLRenderer::attachStencilBufferToLayer(Layer* layer) {
1450    // The layer's FBO is already bound when we reach this stage
1451    if (!layer->getStencilRenderBuffer()) {
1452        // GL_QCOM_tiled_rendering doesn't like it if a renderbuffer
1453        // is attached after we initiated tiling. We must turn it off,
1454        // attach the new render buffer then turn tiling back on
1455        endTiling();
1456
1457        RenderBuffer* buffer = mCaches.renderBufferCache.get(
1458                Stencil::getSmallestStencilFormat(), layer->getWidth(), layer->getHeight());
1459        layer->setStencilRenderBuffer(buffer);
1460
1461        startTiling(layer->clipRect, layer->layer.getHeight());
1462    }
1463}
1464
1465void OpenGLRenderer::setStencilFromClip() {
1466    if (!mCaches.debugOverdraw) {
1467        if (!currentSnapshot()->clipRegion->isEmpty()) {
1468            // NOTE: The order here is important, we must set dirtyClip to false
1469            //       before any draw call to avoid calling back into this method
1470            mDirtyClip = false;
1471
1472            ensureStencilBuffer();
1473
1474            mCaches.stencil.enableWrite();
1475
1476            // Clear and update the stencil, but first make sure we restrict drawing
1477            // to the region's bounds
1478            bool resetScissor = mCaches.enableScissor();
1479            if (resetScissor) {
1480                // The scissor was not set so we now need to update it
1481                setScissorFromClip();
1482            }
1483            mCaches.stencil.clear();
1484
1485            // stash and disable the outline clip state, since stencil doesn't account for outline
1486            bool storedSkipOutlineClip = mSkipOutlineClip;
1487            mSkipOutlineClip = true;
1488
1489            SkPaint paint;
1490            paint.setColor(SK_ColorBLACK);
1491            paint.setXfermodeMode(SkXfermode::kSrc_Mode);
1492
1493            // NOTE: We could use the region contour path to generate a smaller mesh
1494            //       Since we are using the stencil we could use the red book path
1495            //       drawing technique. It might increase bandwidth usage though.
1496
1497            // The last parameter is important: we are not drawing in the color buffer
1498            // so we don't want to dirty the current layer, if any
1499            drawRegionRects(*(currentSnapshot()->clipRegion), paint, false);
1500            if (resetScissor) mCaches.disableScissor();
1501            mSkipOutlineClip = storedSkipOutlineClip;
1502
1503            mCaches.stencil.enableTest();
1504
1505            // Draw the region used to generate the stencil if the appropriate debug
1506            // mode is enabled
1507            if (mCaches.debugStencilClip == Caches::kStencilShowRegion) {
1508                paint.setColor(0x7f0000ff);
1509                paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
1510                drawRegionRects(*(currentSnapshot()->clipRegion), paint);
1511            }
1512        } else {
1513            mCaches.stencil.disable();
1514        }
1515    }
1516}
1517
1518/**
1519 * Returns false and sets scissor enable based upon bounds if drawing won't be clipped out.
1520 *
1521 * @param paint if not null, the bounds will be expanded to account for stroke depending on paint
1522 *         style, and tessellated AA ramp
1523 */
1524bool OpenGLRenderer::quickRejectSetupScissor(float left, float top, float right, float bottom,
1525        const SkPaint* paint) {
1526    bool snapOut = paint && paint->isAntiAlias();
1527
1528    if (paint && paint->getStyle() != SkPaint::kFill_Style) {
1529        float outset = paint->getStrokeWidth() * 0.5f;
1530        left -= outset;
1531        top -= outset;
1532        right += outset;
1533        bottom += outset;
1534    }
1535
1536    bool clipRequired = false;
1537    bool roundRectClipRequired = false;
1538    if (calculateQuickRejectForScissor(left, top, right, bottom,
1539            &clipRequired, &roundRectClipRequired, snapOut)) {
1540        return true;
1541    }
1542
1543    // not quick rejected, so enable the scissor if clipRequired
1544    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
1545    mSkipOutlineClip = !roundRectClipRequired;
1546    return false;
1547}
1548
1549void OpenGLRenderer::debugClip() {
1550#if DEBUG_CLIP_REGIONS
1551    if (!currentSnapshot()->clipRegion->isEmpty()) {
1552        SkPaint paint;
1553        paint.setColor(0x7f00ff00);
1554        drawRegionRects(*(currentSnapshot()->clipRegion, paint);
1555
1556    }
1557#endif
1558}
1559
1560///////////////////////////////////////////////////////////////////////////////
1561// Drawing commands
1562///////////////////////////////////////////////////////////////////////////////
1563
1564void OpenGLRenderer::setupDraw(bool clear) {
1565    // TODO: It would be best if we could do this before quickRejectSetupScissor()
1566    //       changes the scissor test state
1567    if (clear) clearLayerRegions();
1568    // Make sure setScissor & setStencil happen at the beginning of
1569    // this method
1570    if (mDirtyClip) {
1571        if (mCaches.scissorEnabled) {
1572            setScissorFromClip();
1573        }
1574        setStencilFromClip();
1575    }
1576
1577    mDescription.reset();
1578
1579    mSetShaderColor = false;
1580    mColorSet = false;
1581    mColorA = mColorR = mColorG = mColorB = 0.0f;
1582    mTextureUnit = 0;
1583    mTrackDirtyRegions = true;
1584
1585    // Enable debug highlight when what we're about to draw is tested against
1586    // the stencil buffer and if stencil highlight debugging is on
1587    mDescription.hasDebugHighlight = !mCaches.debugOverdraw &&
1588            mCaches.debugStencilClip == Caches::kStencilShowHighlight &&
1589            mCaches.stencil.isTestEnabled();
1590
1591    mDescription.emulateStencil = mCountOverdraw;
1592}
1593
1594void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1595    mDescription.hasTexture = true;
1596    mDescription.hasAlpha8Texture = isAlpha8;
1597}
1598
1599void OpenGLRenderer::setupDrawWithTextureAndColor(bool isAlpha8) {
1600    mDescription.hasTexture = true;
1601    mDescription.hasColors = true;
1602    mDescription.hasAlpha8Texture = isAlpha8;
1603}
1604
1605void OpenGLRenderer::setupDrawWithExternalTexture() {
1606    mDescription.hasExternalTexture = true;
1607}
1608
1609void OpenGLRenderer::setupDrawNoTexture() {
1610    mCaches.disableTexCoordsVertexArray();
1611}
1612
1613void OpenGLRenderer::setupDrawAA() {
1614    mDescription.isAA = true;
1615}
1616
1617void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1618    mColorA = alpha / 255.0f;
1619    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1620    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1621    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1622    mColorSet = true;
1623    mSetShaderColor = mDescription.setColorModulate(mColorA);
1624}
1625
1626void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1627    mColorA = alpha / 255.0f;
1628    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1629    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1630    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1631    mColorSet = true;
1632    mSetShaderColor = mDescription.setAlpha8ColorModulate(mColorR, mColorG, mColorB, mColorA);
1633}
1634
1635void OpenGLRenderer::setupDrawTextGamma(const SkPaint* paint) {
1636    mCaches.fontRenderer->describe(mDescription, paint);
1637}
1638
1639void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1640    mColorA = a;
1641    mColorR = r;
1642    mColorG = g;
1643    mColorB = b;
1644    mColorSet = true;
1645    mSetShaderColor = mDescription.setColorModulate(a);
1646}
1647
1648void OpenGLRenderer::setupDrawShader(const SkShader* shader) {
1649    if (shader != NULL) {
1650        SkiaShader::describe(&mCaches, mDescription, mExtensions, *shader);
1651    }
1652}
1653
1654void OpenGLRenderer::setupDrawColorFilter(const SkColorFilter* filter) {
1655    if (filter == NULL) {
1656        return;
1657    }
1658
1659    SkXfermode::Mode mode;
1660    if (filter->asColorMode(NULL, &mode)) {
1661        mDescription.colorOp = ProgramDescription::kColorBlend;
1662        mDescription.colorMode = mode;
1663    } else if (filter->asColorMatrix(NULL)) {
1664        mDescription.colorOp = ProgramDescription::kColorMatrix;
1665    }
1666}
1667
1668void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1669    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1670        mColorA = 1.0f;
1671        mColorR = mColorG = mColorB = 0.0f;
1672        mSetShaderColor = mDescription.modulate = true;
1673    }
1674}
1675
1676static bool isBlendedColorFilter(const SkColorFilter* filter) {
1677    if (filter == NULL) {
1678        return false;
1679    }
1680    return (filter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag) == 0;
1681}
1682
1683void OpenGLRenderer::setupDrawBlending(const Layer* layer, bool swapSrcDst) {
1684    SkXfermode::Mode mode = layer->getMode();
1685    // When the blending mode is kClear_Mode, we need to use a modulate color
1686    // argb=1,0,0,0
1687    accountForClear(mode);
1688    // TODO: check shader blending, once we have shader drawing support for layers.
1689    bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f ||
1690            (mColorSet && mColorA < 1.0f) || isBlendedColorFilter(layer->getColorFilter());
1691    chooseBlending(blend, mode, mDescription, swapSrcDst);
1692}
1693
1694void OpenGLRenderer::setupDrawBlending(const SkPaint* paint, bool blend, bool swapSrcDst) {
1695    SkXfermode::Mode mode = getXfermodeDirect(paint);
1696    // When the blending mode is kClear_Mode, we need to use a modulate color
1697    // argb=1,0,0,0
1698    accountForClear(mode);
1699    blend |= (mColorSet && mColorA < 1.0f) ||
1700            (getShader(paint) && !getShader(paint)->isOpaque()) ||
1701            isBlendedColorFilter(getColorFilter(paint));
1702    chooseBlending(blend, mode, mDescription, swapSrcDst);
1703}
1704
1705void OpenGLRenderer::setupDrawProgram() {
1706    useProgram(mCaches.programCache.get(mDescription));
1707    if (mDescription.hasRoundRectClip) {
1708        // TODO: avoid doing this repeatedly, stashing state pointer in program
1709        const RoundRectClipState* state = mSnapshot->roundRectClipState;
1710        const Rect& innerRect = state->outlineInnerRect;
1711        glUniform4f(mCaches.currentProgram->getUniform("roundRectInnerRectLTRB"),
1712                innerRect.left,  innerRect.top,
1713                innerRect.right,  innerRect.bottom);
1714        glUniform1f(mCaches.currentProgram->getUniform("roundRectRadius"),
1715                state->outlineRadius);
1716        glUniformMatrix4fv(mCaches.currentProgram->getUniform("roundRectInvTransform"),
1717                1, GL_FALSE, &state->matrix.data[0]);
1718    }
1719}
1720
1721void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1722    mTrackDirtyRegions = false;
1723}
1724
1725void OpenGLRenderer::setupDrawModelView(ModelViewMode mode, bool offset,
1726        float left, float top, float right, float bottom, bool ignoreTransform) {
1727    mModelViewMatrix.loadTranslate(left, top, 0.0f);
1728    if (mode == kModelViewMode_TranslateAndScale) {
1729        mModelViewMatrix.scale(right - left, bottom - top, 1.0f);
1730    }
1731
1732    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1733    const Matrix4& transformMatrix = ignoreTransform ? Matrix4::identity() : *currentTransform();
1734    mCaches.currentProgram->set(mSnapshot->getOrthoMatrix(), mModelViewMatrix, transformMatrix, offset);
1735    if (dirty && mTrackDirtyRegions) {
1736        if (!ignoreTransform) {
1737            dirtyLayer(left, top, right, bottom, *currentTransform());
1738        } else {
1739            dirtyLayer(left, top, right, bottom);
1740        }
1741    }
1742}
1743
1744void OpenGLRenderer::setupDrawColorUniforms(bool hasShader) {
1745    if ((mColorSet && !hasShader) || (hasShader && mSetShaderColor)) {
1746        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1747    }
1748}
1749
1750void OpenGLRenderer::setupDrawPureColorUniforms() {
1751    if (mSetShaderColor) {
1752        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1753    }
1754}
1755
1756void OpenGLRenderer::setupDrawShaderUniforms(const SkShader* shader, bool ignoreTransform) {
1757    if (shader == NULL) {
1758        return;
1759    }
1760
1761    if (ignoreTransform) {
1762        // if ignoreTransform=true was passed to setupDrawModelView, undo currentTransform()
1763        // because it was built into modelView / the geometry, and the description needs to
1764        // compensate.
1765        mat4 modelViewWithoutTransform;
1766        modelViewWithoutTransform.loadInverse(*currentTransform());
1767        modelViewWithoutTransform.multiply(mModelViewMatrix);
1768        mModelViewMatrix.load(modelViewWithoutTransform);
1769    }
1770
1771    SkiaShader::setupProgram(&mCaches, mModelViewMatrix, &mTextureUnit, mExtensions, *shader);
1772}
1773
1774void OpenGLRenderer::setupDrawColorFilterUniforms(const SkColorFilter* filter) {
1775    if (NULL == filter) {
1776        return;
1777    }
1778
1779    SkColor color;
1780    SkXfermode::Mode mode;
1781    if (filter->asColorMode(&color, &mode)) {
1782        const int alpha = SkColorGetA(color);
1783        const GLfloat a = alpha / 255.0f;
1784        const GLfloat r = a * SkColorGetR(color) / 255.0f;
1785        const GLfloat g = a * SkColorGetG(color) / 255.0f;
1786        const GLfloat b = a * SkColorGetB(color) / 255.0f;
1787        glUniform4f(mCaches.currentProgram->getUniform("colorBlend"), r, g, b, a);
1788        return;
1789    }
1790
1791    SkScalar srcColorMatrix[20];
1792    if (filter->asColorMatrix(srcColorMatrix)) {
1793
1794        float colorMatrix[16];
1795        memcpy(colorMatrix, srcColorMatrix, 4 * sizeof(float));
1796        memcpy(&colorMatrix[4], &srcColorMatrix[5], 4 * sizeof(float));
1797        memcpy(&colorMatrix[8], &srcColorMatrix[10], 4 * sizeof(float));
1798        memcpy(&colorMatrix[12], &srcColorMatrix[15], 4 * sizeof(float));
1799
1800        // Skia uses the range [0..255] for the addition vector, but we need
1801        // the [0..1] range to apply the vector in GLSL
1802        float colorVector[4];
1803        colorVector[0] = srcColorMatrix[4] / 255.0f;
1804        colorVector[1] = srcColorMatrix[9] / 255.0f;
1805        colorVector[2] = srcColorMatrix[14] / 255.0f;
1806        colorVector[3] = srcColorMatrix[19] / 255.0f;
1807
1808        glUniformMatrix4fv(mCaches.currentProgram->getUniform("colorMatrix"), 1,
1809                GL_FALSE, colorMatrix);
1810        glUniform4fv(mCaches.currentProgram->getUniform("colorMatrixVector"), 1, colorVector);
1811        return;
1812    }
1813
1814    // it is an error if we ever get here
1815}
1816
1817void OpenGLRenderer::setupDrawTextGammaUniforms() {
1818    mCaches.fontRenderer->setupProgram(mDescription, mCaches.currentProgram);
1819}
1820
1821void OpenGLRenderer::setupDrawSimpleMesh() {
1822    bool force = mCaches.bindMeshBuffer();
1823    mCaches.bindPositionVertexPointer(force, 0);
1824    mCaches.unbindIndicesBuffer();
1825}
1826
1827void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1828    if (texture) bindTexture(texture);
1829    mTextureUnit++;
1830    mCaches.enableTexCoordsVertexArray();
1831}
1832
1833void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1834    bindExternalTexture(texture);
1835    mTextureUnit++;
1836    mCaches.enableTexCoordsVertexArray();
1837}
1838
1839void OpenGLRenderer::setupDrawTextureTransform() {
1840    mDescription.hasTextureTransform = true;
1841}
1842
1843void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1844    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1845            GL_FALSE, &transform.data[0]);
1846}
1847
1848void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1849        const GLvoid* texCoords, GLuint vbo) {
1850    bool force = false;
1851    if (!vertices || vbo) {
1852        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1853    } else {
1854        force = mCaches.unbindMeshBuffer();
1855    }
1856
1857    mCaches.bindPositionVertexPointer(force, vertices);
1858    if (mCaches.currentProgram->texCoords >= 0) {
1859        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1860    }
1861
1862    mCaches.unbindIndicesBuffer();
1863}
1864
1865void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1866        const GLvoid* texCoords, const GLvoid* colors) {
1867    bool force = mCaches.unbindMeshBuffer();
1868    GLsizei stride = sizeof(ColorTextureVertex);
1869
1870    mCaches.bindPositionVertexPointer(force, vertices, stride);
1871    if (mCaches.currentProgram->texCoords >= 0) {
1872        mCaches.bindTexCoordsVertexPointer(force, texCoords, stride);
1873    }
1874    int slot = mCaches.currentProgram->getAttrib("colors");
1875    if (slot >= 0) {
1876        glEnableVertexAttribArray(slot);
1877        glVertexAttribPointer(slot, 4, GL_FLOAT, GL_FALSE, stride, colors);
1878    }
1879
1880    mCaches.unbindIndicesBuffer();
1881}
1882
1883void OpenGLRenderer::setupDrawMeshIndices(const GLvoid* vertices,
1884        const GLvoid* texCoords, GLuint vbo) {
1885    bool force = false;
1886    // If vbo is != 0 we want to treat the vertices parameter as an offset inside
1887    // a VBO. However, if vertices is set to NULL and vbo == 0 then we want to
1888    // use the default VBO found in Caches
1889    if (!vertices || vbo) {
1890        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1891    } else {
1892        force = mCaches.unbindMeshBuffer();
1893    }
1894    mCaches.bindQuadIndicesBuffer();
1895
1896    mCaches.bindPositionVertexPointer(force, vertices);
1897    if (mCaches.currentProgram->texCoords >= 0) {
1898        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1899    }
1900}
1901
1902void OpenGLRenderer::setupDrawIndexedVertices(GLvoid* vertices) {
1903    bool force = mCaches.unbindMeshBuffer();
1904    mCaches.bindQuadIndicesBuffer();
1905    mCaches.bindPositionVertexPointer(force, vertices, gVertexStride);
1906}
1907
1908///////////////////////////////////////////////////////////////////////////////
1909// Drawing
1910///////////////////////////////////////////////////////////////////////////////
1911
1912status_t OpenGLRenderer::drawRenderNode(RenderNode* renderNode, Rect& dirty, int32_t replayFlags) {
1913    status_t status;
1914    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1915    // will be performed by the display list itself
1916    if (renderNode && renderNode->isRenderable()) {
1917        // compute 3d ordering
1918        renderNode->computeOrdering();
1919        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
1920            status = startFrame();
1921            ReplayStateStruct replayStruct(*this, dirty, replayFlags);
1922            renderNode->replay(replayStruct, 0);
1923            return status | replayStruct.mDrawGlStatus;
1924        }
1925
1926        bool avoidOverdraw = !mCaches.debugOverdraw && !mCountOverdraw; // shh, don't tell devs!
1927        DeferredDisplayList deferredList(*currentClipRect(), avoidOverdraw);
1928        DeferStateStruct deferStruct(deferredList, *this, replayFlags);
1929        renderNode->defer(deferStruct, 0);
1930
1931        flushLayers();
1932        status = startFrame();
1933
1934        return deferredList.flush(*this, dirty) | status;
1935    }
1936
1937    // Even if there is no drawing command(Ex: invisible),
1938    // it still needs startFrame to clear buffer and start tiling.
1939    return startFrame();
1940}
1941
1942void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, const SkPaint* paint) {
1943    int color = paint != NULL ? paint->getColor() : 0;
1944
1945    float x = left;
1946    float y = top;
1947
1948    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1949
1950    bool ignoreTransform = false;
1951    if (currentTransform()->isPureTranslate()) {
1952        x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
1953        y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
1954        ignoreTransform = true;
1955
1956        texture->setFilter(GL_NEAREST, true);
1957    } else {
1958        texture->setFilter(getFilter(paint), true);
1959    }
1960
1961    // No need to check for a UV mapper on the texture object, only ARGB_8888
1962    // bitmaps get packed in the atlas
1963    drawAlpha8TextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1964            paint, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1965            GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
1966}
1967
1968/**
1969 * Important note: this method is intended to draw batches of bitmaps and
1970 * will not set the scissor enable or dirty the current layer, if any.
1971 * The caller is responsible for properly dirtying the current layer.
1972 */
1973status_t OpenGLRenderer::drawBitmaps(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
1974        int bitmapCount, TextureVertex* vertices, bool pureTranslate,
1975        const Rect& bounds, const SkPaint* paint) {
1976    mCaches.activeTexture(0);
1977    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
1978    if (!texture) return DrawGlInfo::kStatusDone;
1979
1980    const AutoTexture autoCleanup(texture);
1981
1982    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1983    texture->setFilter(pureTranslate ? GL_NEAREST : getFilter(paint), true);
1984
1985    const float x = (int) floorf(bounds.left + 0.5f);
1986    const float y = (int) floorf(bounds.top + 0.5f);
1987    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
1988        drawAlpha8TextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1989                texture->id, paint, &vertices[0].x, &vertices[0].u,
1990                GL_TRIANGLES, bitmapCount * 6, true,
1991                kModelViewMode_Translate, false);
1992    } else {
1993        drawTextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1994                texture->id, paint, texture->blend, &vertices[0].x, &vertices[0].u,
1995                GL_TRIANGLES, bitmapCount * 6, false, true, 0,
1996                kModelViewMode_Translate, false);
1997    }
1998
1999    return DrawGlInfo::kStatusDrew;
2000}
2001
2002status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap, float left, float top,
2003        const SkPaint* paint) {
2004    const float right = left + bitmap->width();
2005    const float bottom = top + bitmap->height();
2006
2007    if (quickRejectSetupScissor(left, top, right, bottom)) {
2008        return DrawGlInfo::kStatusDone;
2009    }
2010
2011    mCaches.activeTexture(0);
2012    Texture* texture = getTexture(bitmap);
2013    if (!texture) return DrawGlInfo::kStatusDone;
2014    const AutoTexture autoCleanup(texture);
2015
2016    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2017        drawAlphaBitmap(texture, left, top, paint);
2018    } else {
2019        drawTextureRect(left, top, right, bottom, texture, paint);
2020    }
2021
2022    return DrawGlInfo::kStatusDrew;
2023}
2024
2025status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap, const SkMatrix& matrix,
2026        const SkPaint* paint) {
2027    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
2028    const mat4 transform(matrix);
2029    transform.mapRect(r);
2030
2031    if (quickRejectSetupScissor(r.left, r.top, r.right, r.bottom)) {
2032        return DrawGlInfo::kStatusDone;
2033    }
2034
2035    mCaches.activeTexture(0);
2036    Texture* texture = getTexture(bitmap);
2037    if (!texture) return DrawGlInfo::kStatusDone;
2038    const AutoTexture autoCleanup(texture);
2039
2040    // This could be done in a cheaper way, all we need is pass the matrix
2041    // to the vertex shader. The save/restore is a bit overkill.
2042    save(SkCanvas::kMatrix_SaveFlag);
2043    concatMatrix(matrix);
2044    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2045        drawAlphaBitmap(texture, 0.0f, 0.0f, paint);
2046    } else {
2047        drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
2048    }
2049    restore();
2050
2051    return DrawGlInfo::kStatusDrew;
2052}
2053
2054status_t OpenGLRenderer::drawBitmapData(const SkBitmap* bitmap, float left, float top,
2055        const SkPaint* paint) {
2056    const float right = left + bitmap->width();
2057    const float bottom = top + bitmap->height();
2058
2059    if (quickRejectSetupScissor(left, top, right, bottom)) {
2060        return DrawGlInfo::kStatusDone;
2061    }
2062
2063    mCaches.activeTexture(0);
2064    Texture* texture = mCaches.textureCache.getTransient(bitmap);
2065    const AutoTexture autoCleanup(texture);
2066
2067    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2068        drawAlphaBitmap(texture, left, top, paint);
2069    } else {
2070        drawTextureRect(left, top, right, bottom, texture, paint);
2071    }
2072
2073    return DrawGlInfo::kStatusDrew;
2074}
2075
2076status_t OpenGLRenderer::drawBitmapMesh(const SkBitmap* bitmap, int meshWidth, int meshHeight,
2077        const float* vertices, const int* colors, const SkPaint* paint) {
2078    if (!vertices || currentSnapshot()->isIgnored()) {
2079        return DrawGlInfo::kStatusDone;
2080    }
2081
2082    // TODO: use quickReject on bounds from vertices
2083    mCaches.enableScissor();
2084
2085    float left = FLT_MAX;
2086    float top = FLT_MAX;
2087    float right = FLT_MIN;
2088    float bottom = FLT_MIN;
2089
2090    const uint32_t count = meshWidth * meshHeight * 6;
2091
2092    Vector<ColorTextureVertex> mesh; // TODO: use C++11 unique_ptr
2093    mesh.setCapacity(count);
2094    ColorTextureVertex* vertex = mesh.editArray();
2095
2096    bool cleanupColors = false;
2097    if (!colors) {
2098        uint32_t colorsCount = (meshWidth + 1) * (meshHeight + 1);
2099        int* newColors = new int[colorsCount];
2100        memset(newColors, 0xff, colorsCount * sizeof(int));
2101        colors = newColors;
2102        cleanupColors = true;
2103    }
2104
2105    mCaches.activeTexture(0);
2106    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
2107    const UvMapper& mapper(getMapper(texture));
2108
2109    for (int32_t y = 0; y < meshHeight; y++) {
2110        for (int32_t x = 0; x < meshWidth; x++) {
2111            uint32_t i = (y * (meshWidth + 1) + x) * 2;
2112
2113            float u1 = float(x) / meshWidth;
2114            float u2 = float(x + 1) / meshWidth;
2115            float v1 = float(y) / meshHeight;
2116            float v2 = float(y + 1) / meshHeight;
2117
2118            mapper.map(u1, v1, u2, v2);
2119
2120            int ax = i + (meshWidth + 1) * 2;
2121            int ay = ax + 1;
2122            int bx = i;
2123            int by = bx + 1;
2124            int cx = i + 2;
2125            int cy = cx + 1;
2126            int dx = i + (meshWidth + 1) * 2 + 2;
2127            int dy = dx + 1;
2128
2129            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2130            ColorTextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2, colors[ax / 2]);
2131            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2132
2133            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2134            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2135            ColorTextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1, colors[cx / 2]);
2136
2137            left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
2138            top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
2139            right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
2140            bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
2141        }
2142    }
2143
2144    if (quickRejectSetupScissor(left, top, right, bottom)) {
2145        if (cleanupColors) delete[] colors;
2146        return DrawGlInfo::kStatusDone;
2147    }
2148
2149    if (!texture) {
2150        texture = mCaches.textureCache.get(bitmap);
2151        if (!texture) {
2152            if (cleanupColors) delete[] colors;
2153            return DrawGlInfo::kStatusDone;
2154        }
2155    }
2156    const AutoTexture autoCleanup(texture);
2157
2158    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2159    texture->setFilter(getFilter(paint), true);
2160
2161    int alpha;
2162    SkXfermode::Mode mode;
2163    getAlphaAndMode(paint, &alpha, &mode);
2164
2165    float a = alpha / 255.0f;
2166
2167    if (hasLayer()) {
2168        dirtyLayer(left, top, right, bottom, *currentTransform());
2169    }
2170
2171    setupDraw();
2172    setupDrawWithTextureAndColor();
2173    setupDrawColor(a, a, a, a);
2174    setupDrawColorFilter(getColorFilter(paint));
2175    setupDrawBlending(paint, true);
2176    setupDrawProgram();
2177    setupDrawDirtyRegionsDisabled();
2178    setupDrawModelView(kModelViewMode_TranslateAndScale, false, 0.0f, 0.0f, 1.0f, 1.0f);
2179    setupDrawTexture(texture->id);
2180    setupDrawPureColorUniforms();
2181    setupDrawColorFilterUniforms(getColorFilter(paint));
2182    setupDrawMesh(&mesh[0].x, &mesh[0].u, &mesh[0].r);
2183
2184    glDrawArrays(GL_TRIANGLES, 0, count);
2185
2186    int slot = mCaches.currentProgram->getAttrib("colors");
2187    if (slot >= 0) {
2188        glDisableVertexAttribArray(slot);
2189    }
2190
2191    if (cleanupColors) delete[] colors;
2192
2193    return DrawGlInfo::kStatusDrew;
2194}
2195
2196status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap,
2197         float srcLeft, float srcTop, float srcRight, float srcBottom,
2198         float dstLeft, float dstTop, float dstRight, float dstBottom,
2199         const SkPaint* paint) {
2200    if (quickRejectSetupScissor(dstLeft, dstTop, dstRight, dstBottom)) {
2201        return DrawGlInfo::kStatusDone;
2202    }
2203
2204    mCaches.activeTexture(0);
2205    Texture* texture = getTexture(bitmap);
2206    if (!texture) return DrawGlInfo::kStatusDone;
2207    const AutoTexture autoCleanup(texture);
2208
2209    const float width = texture->width;
2210    const float height = texture->height;
2211
2212    float u1 = fmax(0.0f, srcLeft / width);
2213    float v1 = fmax(0.0f, srcTop / height);
2214    float u2 = fmin(1.0f, srcRight / width);
2215    float v2 = fmin(1.0f, srcBottom / height);
2216
2217    getMapper(texture).map(u1, v1, u2, v2);
2218
2219    mCaches.unbindMeshBuffer();
2220    resetDrawTextureTexCoords(u1, v1, u2, v2);
2221
2222    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2223
2224    float scaleX = (dstRight - dstLeft) / (srcRight - srcLeft);
2225    float scaleY = (dstBottom - dstTop) / (srcBottom - srcTop);
2226
2227    bool scaled = scaleX != 1.0f || scaleY != 1.0f;
2228    // Apply a scale transform on the canvas only when a shader is in use
2229    // Skia handles the ratio between the dst and src rects as a scale factor
2230    // when a shader is set
2231    bool useScaleTransform = getShader(paint) && scaled;
2232    bool ignoreTransform = false;
2233
2234    if (CC_LIKELY(currentTransform()->isPureTranslate() && !useScaleTransform)) {
2235        float x = (int) floorf(dstLeft + currentTransform()->getTranslateX() + 0.5f);
2236        float y = (int) floorf(dstTop + currentTransform()->getTranslateY() + 0.5f);
2237
2238        dstRight = x + (dstRight - dstLeft);
2239        dstBottom = y + (dstBottom - dstTop);
2240
2241        dstLeft = x;
2242        dstTop = y;
2243
2244        texture->setFilter(scaled ? getFilter(paint) : GL_NEAREST, true);
2245        ignoreTransform = true;
2246    } else {
2247        texture->setFilter(getFilter(paint), true);
2248    }
2249
2250    if (CC_UNLIKELY(useScaleTransform)) {
2251        save(SkCanvas::kMatrix_SaveFlag);
2252        translate(dstLeft, dstTop);
2253        scale(scaleX, scaleY);
2254
2255        dstLeft = 0.0f;
2256        dstTop = 0.0f;
2257
2258        dstRight = srcRight - srcLeft;
2259        dstBottom = srcBottom - srcTop;
2260    }
2261
2262    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2263        drawAlpha8TextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2264                texture->id, paint,
2265                &mMeshVertices[0].x, &mMeshVertices[0].u,
2266                GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
2267    } else {
2268        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2269                texture->id, paint, texture->blend,
2270                &mMeshVertices[0].x, &mMeshVertices[0].u,
2271                GL_TRIANGLE_STRIP, gMeshCount, false, ignoreTransform);
2272    }
2273
2274    if (CC_UNLIKELY(useScaleTransform)) {
2275        restore();
2276    }
2277
2278    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
2279
2280    return DrawGlInfo::kStatusDrew;
2281}
2282
2283status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Res_png_9patch* patch,
2284        float left, float top, float right, float bottom, const SkPaint* paint) {
2285    if (quickRejectSetupScissor(left, top, right, bottom)) {
2286        return DrawGlInfo::kStatusDone;
2287    }
2288
2289    AssetAtlas::Entry* entry = mCaches.assetAtlas.getEntry(bitmap);
2290    const Patch* mesh = mCaches.patchCache.get(entry, bitmap->width(), bitmap->height(),
2291            right - left, bottom - top, patch);
2292
2293    return drawPatch(bitmap, mesh, entry, left, top, right, bottom, paint);
2294}
2295
2296status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Patch* mesh,
2297        AssetAtlas::Entry* entry, float left, float top, float right, float bottom,
2298        const SkPaint* paint) {
2299    if (quickRejectSetupScissor(left, top, right, bottom)) {
2300        return DrawGlInfo::kStatusDone;
2301    }
2302
2303    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
2304        mCaches.activeTexture(0);
2305        Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2306        if (!texture) return DrawGlInfo::kStatusDone;
2307        const AutoTexture autoCleanup(texture);
2308
2309        texture->setWrap(GL_CLAMP_TO_EDGE, true);
2310        texture->setFilter(GL_LINEAR, true);
2311
2312        const bool pureTranslate = currentTransform()->isPureTranslate();
2313        // Mark the current layer dirty where we are going to draw the patch
2314        if (hasLayer() && mesh->hasEmptyQuads) {
2315            const float offsetX = left + currentTransform()->getTranslateX();
2316            const float offsetY = top + currentTransform()->getTranslateY();
2317            const size_t count = mesh->quads.size();
2318            for (size_t i = 0; i < count; i++) {
2319                const Rect& bounds = mesh->quads.itemAt(i);
2320                if (CC_LIKELY(pureTranslate)) {
2321                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
2322                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
2323                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
2324                } else {
2325                    dirtyLayer(left + bounds.left, top + bounds.top,
2326                            left + bounds.right, top + bounds.bottom, *currentTransform());
2327                }
2328            }
2329        }
2330
2331        bool ignoreTransform = false;
2332        if (CC_LIKELY(pureTranslate)) {
2333            const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
2334            const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
2335
2336            right = x + right - left;
2337            bottom = y + bottom - top;
2338            left = x;
2339            top = y;
2340            ignoreTransform = true;
2341        }
2342        drawIndexedTextureMesh(left, top, right, bottom, texture->id, paint,
2343                texture->blend, (GLvoid*) mesh->offset, (GLvoid*) mesh->textureOffset,
2344                GL_TRIANGLES, mesh->indexCount, false, ignoreTransform,
2345                mCaches.patchCache.getMeshBuffer(), kModelViewMode_Translate, !mesh->hasEmptyQuads);
2346    }
2347
2348    return DrawGlInfo::kStatusDrew;
2349}
2350
2351/**
2352 * Important note: this method is intended to draw batches of 9-patch objects and
2353 * will not set the scissor enable or dirty the current layer, if any.
2354 * The caller is responsible for properly dirtying the current layer.
2355 */
2356status_t OpenGLRenderer::drawPatches(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
2357        TextureVertex* vertices, uint32_t indexCount, const SkPaint* paint) {
2358    mCaches.activeTexture(0);
2359    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2360    if (!texture) return DrawGlInfo::kStatusDone;
2361    const AutoTexture autoCleanup(texture);
2362
2363    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2364    texture->setFilter(GL_LINEAR, true);
2365
2366    drawIndexedTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, paint,
2367            texture->blend, &vertices[0].x, &vertices[0].u,
2368            GL_TRIANGLES, indexCount, false, true, 0, kModelViewMode_Translate, false);
2369
2370    return DrawGlInfo::kStatusDrew;
2371}
2372
2373status_t OpenGLRenderer::drawVertexBuffer(float translateX, float translateY,
2374        const VertexBuffer& vertexBuffer, const SkPaint* paint, bool useOffset) {
2375    // not missing call to quickReject/dirtyLayer, always done at a higher level
2376    if (!vertexBuffer.getVertexCount()) {
2377        // no vertices to draw
2378        return DrawGlInfo::kStatusDone;
2379    }
2380
2381    Rect bounds(vertexBuffer.getBounds());
2382    bounds.translate(translateX, translateY);
2383    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom, *currentTransform());
2384
2385    int color = paint->getColor();
2386    bool isAA = paint->isAntiAlias();
2387
2388    setupDraw();
2389    setupDrawNoTexture();
2390    if (isAA) setupDrawAA();
2391    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
2392    setupDrawColorFilter(getColorFilter(paint));
2393    setupDrawShader(getShader(paint));
2394    setupDrawBlending(paint, isAA);
2395    setupDrawProgram();
2396    setupDrawModelView(kModelViewMode_Translate, useOffset, translateX, translateY, 0, 0);
2397    setupDrawColorUniforms(getShader(paint));
2398    setupDrawColorFilterUniforms(getColorFilter(paint));
2399    setupDrawShaderUniforms(getShader(paint));
2400
2401    const void* vertices = vertexBuffer.getBuffer();
2402    bool force = mCaches.unbindMeshBuffer();
2403    mCaches.bindPositionVertexPointer(true, vertices, isAA ? gAlphaVertexStride : gVertexStride);
2404    mCaches.resetTexCoordsVertexPointer();
2405
2406
2407    int alphaSlot = -1;
2408    if (isAA) {
2409        void* alphaCoords = ((GLbyte*) vertices) + gVertexAlphaOffset;
2410        alphaSlot = mCaches.currentProgram->getAttrib("vtxAlpha");
2411        // TODO: avoid enable/disable in back to back uses of the alpha attribute
2412        glEnableVertexAttribArray(alphaSlot);
2413        glVertexAttribPointer(alphaSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, alphaCoords);
2414    }
2415
2416    const VertexBuffer::Mode mode = vertexBuffer.getMode();
2417    if (mode == VertexBuffer::kStandard) {
2418        mCaches.unbindIndicesBuffer();
2419        glDrawArrays(GL_TRIANGLE_STRIP, 0, vertexBuffer.getVertexCount());
2420    } else if (mode == VertexBuffer::kOnePolyRingShadow) {
2421        mCaches.bindShadowIndicesBuffer();
2422        glDrawElements(GL_TRIANGLE_STRIP, ONE_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2423    } else if (mode == VertexBuffer::kTwoPolyRingShadow) {
2424        mCaches.bindShadowIndicesBuffer();
2425        glDrawElements(GL_TRIANGLE_STRIP, TWO_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2426    }
2427
2428    if (isAA) {
2429        glDisableVertexAttribArray(alphaSlot);
2430    }
2431
2432    return DrawGlInfo::kStatusDrew;
2433}
2434
2435/**
2436 * Renders a convex path via tessellation. For AA paths, this function uses a similar approach to
2437 * that of AA lines in the drawLines() function.  We expand the convex path by a half pixel in
2438 * screen space in all directions. However, instead of using a fragment shader to compute the
2439 * translucency of the color from its position, we simply use a varying parameter to define how far
2440 * a given pixel is from the edge. For non-AA paths, the expansion and alpha varying are not used.
2441 *
2442 * Doesn't yet support joins, caps, or path effects.
2443 */
2444status_t OpenGLRenderer::drawConvexPath(const SkPath& path, const SkPaint* paint) {
2445    VertexBuffer vertexBuffer;
2446    // TODO: try clipping large paths to viewport
2447    PathTessellator::tessellatePath(path, paint, *currentTransform(), vertexBuffer);
2448    return drawVertexBuffer(vertexBuffer, paint);
2449}
2450
2451/**
2452 * We create tristrips for the lines much like shape stroke tessellation, using a per-vertex alpha
2453 * and additional geometry for defining an alpha slope perimeter.
2454 *
2455 * Using GL_LINES can be difficult because the rasterization rules for those lines produces some
2456 * unexpected results, and may vary between hardware devices. Previously we used a varying-base
2457 * in-shader alpha region, but found it to be taxing on some GPUs.
2458 *
2459 * TODO: try using a fixed input buffer for non-capped lines as in text rendering. this may reduce
2460 * memory transfer by removing need for degenerate vertices.
2461 */
2462status_t OpenGLRenderer::drawLines(const float* points, int count, const SkPaint* paint) {
2463    if (currentSnapshot()->isIgnored() || count < 4) return DrawGlInfo::kStatusDone;
2464
2465    count &= ~0x3; // round down to nearest four
2466
2467    VertexBuffer buffer;
2468    PathTessellator::tessellateLines(points, count, paint, *currentTransform(), buffer);
2469    const Rect& bounds = buffer.getBounds();
2470
2471    if (quickRejectSetupScissor(bounds.left, bounds.top, bounds.right, bounds.bottom)) {
2472        return DrawGlInfo::kStatusDone;
2473    }
2474
2475    bool useOffset = !paint->isAntiAlias();
2476    return drawVertexBuffer(buffer, paint, useOffset);
2477}
2478
2479status_t OpenGLRenderer::drawPoints(const float* points, int count, const SkPaint* paint) {
2480    if (currentSnapshot()->isIgnored() || count < 2) return DrawGlInfo::kStatusDone;
2481
2482    count &= ~0x1; // round down to nearest two
2483
2484    VertexBuffer buffer;
2485    PathTessellator::tessellatePoints(points, count, paint, *currentTransform(), buffer);
2486
2487    const Rect& bounds = buffer.getBounds();
2488    if (quickRejectSetupScissor(bounds.left, bounds.top, bounds.right, bounds.bottom)) {
2489        return DrawGlInfo::kStatusDone;
2490    }
2491
2492    bool useOffset = !paint->isAntiAlias();
2493    return drawVertexBuffer(buffer, paint, useOffset);
2494}
2495
2496status_t OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
2497    // No need to check against the clip, we fill the clip region
2498    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
2499
2500    Rect clip(*currentClipRect());
2501    clip.snapToPixelBoundaries();
2502
2503    SkPaint paint;
2504    paint.setColor(color);
2505    paint.setXfermodeMode(mode);
2506
2507    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, &paint, true);
2508
2509    return DrawGlInfo::kStatusDrew;
2510}
2511
2512status_t OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture,
2513        const SkPaint* paint) {
2514    if (!texture) return DrawGlInfo::kStatusDone;
2515    const AutoTexture autoCleanup(texture);
2516
2517    const float x = left + texture->left - texture->offset;
2518    const float y = top + texture->top - texture->offset;
2519
2520    drawPathTexture(texture, x, y, paint);
2521
2522    return DrawGlInfo::kStatusDrew;
2523}
2524
2525status_t OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
2526        float rx, float ry, const SkPaint* p) {
2527    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2528            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2529        return DrawGlInfo::kStatusDone;
2530    }
2531
2532    if (p->getPathEffect() != 0) {
2533        mCaches.activeTexture(0);
2534        const PathTexture* texture = mCaches.pathCache.getRoundRect(
2535                right - left, bottom - top, rx, ry, p);
2536        return drawShape(left, top, texture, p);
2537    }
2538
2539    const VertexBuffer* vertexBuffer = mCaches.tessellationCache.getRoundRect(
2540            *currentTransform(), *p, right - left, bottom - top, rx, ry);
2541    return drawVertexBuffer(left, top, *vertexBuffer, p);
2542}
2543
2544status_t OpenGLRenderer::drawCircle(float x, float y, float radius, const SkPaint* p) {
2545    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(x - radius, y - radius,
2546            x + radius, y + radius, p) ||
2547            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2548        return DrawGlInfo::kStatusDone;
2549    }
2550    if (p->getPathEffect() != 0) {
2551        mCaches.activeTexture(0);
2552        const PathTexture* texture = mCaches.pathCache.getCircle(radius, p);
2553        return drawShape(x - radius, y - radius, texture, p);
2554    }
2555
2556    SkPath path;
2557    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2558        path.addCircle(x, y, radius + p->getStrokeWidth() / 2);
2559    } else {
2560        path.addCircle(x, y, radius);
2561    }
2562    return drawConvexPath(path, p);
2563}
2564
2565status_t OpenGLRenderer::drawOval(float left, float top, float right, float bottom,
2566        const SkPaint* p) {
2567    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2568            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2569        return DrawGlInfo::kStatusDone;
2570    }
2571
2572    if (p->getPathEffect() != 0) {
2573        mCaches.activeTexture(0);
2574        const PathTexture* texture = mCaches.pathCache.getOval(right - left, bottom - top, p);
2575        return drawShape(left, top, texture, p);
2576    }
2577
2578    SkPath path;
2579    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2580    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2581        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2582    }
2583    path.addOval(rect);
2584    return drawConvexPath(path, p);
2585}
2586
2587status_t OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2588        float startAngle, float sweepAngle, bool useCenter, const SkPaint* p) {
2589    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2590            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2591        return DrawGlInfo::kStatusDone;
2592    }
2593
2594    // TODO: support fills (accounting for concavity if useCenter && sweepAngle > 180)
2595    if (p->getStyle() != SkPaint::kStroke_Style || p->getPathEffect() != 0 || useCenter) {
2596        mCaches.activeTexture(0);
2597        const PathTexture* texture = mCaches.pathCache.getArc(right - left, bottom - top,
2598                startAngle, sweepAngle, useCenter, p);
2599        return drawShape(left, top, texture, p);
2600    }
2601
2602    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2603    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2604        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2605    }
2606
2607    SkPath path;
2608    if (useCenter) {
2609        path.moveTo(rect.centerX(), rect.centerY());
2610    }
2611    path.arcTo(rect, startAngle, sweepAngle, !useCenter);
2612    if (useCenter) {
2613        path.close();
2614    }
2615    return drawConvexPath(path, p);
2616}
2617
2618// See SkPaintDefaults.h
2619#define SkPaintDefaults_MiterLimit SkIntToScalar(4)
2620
2621status_t OpenGLRenderer::drawRect(float left, float top, float right, float bottom,
2622        const SkPaint* p) {
2623    if (currentSnapshot()->isIgnored() || quickRejectSetupScissor(left, top, right, bottom, p) ||
2624            (p->getAlpha() == 0 && getXfermode(p->getXfermode()) != SkXfermode::kClear_Mode)) {
2625        return DrawGlInfo::kStatusDone;
2626    }
2627
2628    if (p->getStyle() != SkPaint::kFill_Style) {
2629        // only fill style is supported by drawConvexPath, since others have to handle joins
2630        if (p->getPathEffect() != 0 || p->getStrokeJoin() != SkPaint::kMiter_Join ||
2631                p->getStrokeMiter() != SkPaintDefaults_MiterLimit) {
2632            mCaches.activeTexture(0);
2633            const PathTexture* texture =
2634                    mCaches.pathCache.getRect(right - left, bottom - top, p);
2635            return drawShape(left, top, texture, p);
2636        }
2637
2638        SkPath path;
2639        SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2640        if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2641            rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2642        }
2643        path.addRect(rect);
2644        return drawConvexPath(path, p);
2645    }
2646
2647    if (p->isAntiAlias() && !currentTransform()->isSimple()) {
2648        SkPath path;
2649        path.addRect(left, top, right, bottom);
2650        return drawConvexPath(path, p);
2651    } else {
2652        drawColorRect(left, top, right, bottom, p);
2653        return DrawGlInfo::kStatusDrew;
2654    }
2655}
2656
2657void OpenGLRenderer::drawTextShadow(const SkPaint* paint, const char* text,
2658        int bytesCount, int count, const float* positions,
2659        FontRenderer& fontRenderer, int alpha, float x, float y) {
2660    mCaches.activeTexture(0);
2661
2662    TextShadow textShadow;
2663    if (!getTextShadow(paint, &textShadow)) {
2664        LOG_ALWAYS_FATAL("failed to query shadow attributes");
2665    }
2666
2667    // NOTE: The drop shadow will not perform gamma correction
2668    //       if shader-based correction is enabled
2669    mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2670    const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2671            paint, text, bytesCount, count, textShadow.radius, positions);
2672    // If the drop shadow exceeds the max texture size or couldn't be
2673    // allocated, skip drawing
2674    if (!shadow) return;
2675    const AutoTexture autoCleanup(shadow);
2676
2677    const float sx = x - shadow->left + textShadow.dx;
2678    const float sy = y - shadow->top + textShadow.dy;
2679
2680    const int shadowAlpha = ((textShadow.color >> 24) & 0xFF) * mSnapshot->alpha;
2681    if (getShader(paint)) {
2682        textShadow.color = SK_ColorWHITE;
2683    }
2684
2685    setupDraw();
2686    setupDrawWithTexture(true);
2687    setupDrawAlpha8Color(textShadow.color, shadowAlpha < 255 ? shadowAlpha : alpha);
2688    setupDrawColorFilter(getColorFilter(paint));
2689    setupDrawShader(getShader(paint));
2690    setupDrawBlending(paint, true);
2691    setupDrawProgram();
2692    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
2693            sx, sy, sx + shadow->width, sy + shadow->height);
2694    setupDrawTexture(shadow->id);
2695    setupDrawPureColorUniforms();
2696    setupDrawColorFilterUniforms(getColorFilter(paint));
2697    setupDrawShaderUniforms(getShader(paint));
2698    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2699
2700    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2701}
2702
2703bool OpenGLRenderer::canSkipText(const SkPaint* paint) const {
2704    float alpha = (hasTextShadow(paint) ? 1.0f : paint->getAlpha()) * mSnapshot->alpha;
2705    return alpha == 0.0f && getXfermode(paint->getXfermode()) == SkXfermode::kSrcOver_Mode;
2706}
2707
2708status_t OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2709        const float* positions, const SkPaint* paint) {
2710    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2711        return DrawGlInfo::kStatusDone;
2712    }
2713
2714    // NOTE: Skia does not support perspective transform on drawPosText yet
2715    if (!currentTransform()->isSimple()) {
2716        return DrawGlInfo::kStatusDone;
2717    }
2718
2719    mCaches.enableScissor();
2720
2721    float x = 0.0f;
2722    float y = 0.0f;
2723    const bool pureTranslate = currentTransform()->isPureTranslate();
2724    if (pureTranslate) {
2725        x = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2726        y = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2727    }
2728
2729    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2730    fontRenderer.setFont(paint, SkMatrix::I());
2731
2732    int alpha;
2733    SkXfermode::Mode mode;
2734    getAlphaAndMode(paint, &alpha, &mode);
2735
2736    if (CC_UNLIKELY(hasTextShadow(paint))) {
2737        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2738                alpha, 0.0f, 0.0f);
2739    }
2740
2741    // Pick the appropriate texture filtering
2742    bool linearFilter = currentTransform()->changesBounds();
2743    if (pureTranslate && !linearFilter) {
2744        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2745    }
2746    fontRenderer.setTextureFiltering(linearFilter);
2747
2748    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2749    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2750
2751    const bool hasActiveLayer = hasLayer();
2752
2753    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2754    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2755            positions, hasActiveLayer ? &bounds : NULL, &functor)) {
2756        if (hasActiveLayer) {
2757            if (!pureTranslate) {
2758                currentTransform()->mapRect(bounds);
2759            }
2760            dirtyLayerUnchecked(bounds, getRegion());
2761        }
2762    }
2763
2764    return DrawGlInfo::kStatusDrew;
2765}
2766
2767bool OpenGLRenderer::findBestFontTransform(const mat4& transform, SkMatrix* outMatrix) const {
2768    if (CC_LIKELY(transform.isPureTranslate())) {
2769        outMatrix->setIdentity();
2770        return false;
2771    } else if (CC_UNLIKELY(transform.isPerspective())) {
2772        outMatrix->setIdentity();
2773        return true;
2774    }
2775
2776    /**
2777     * Input is a non-perspective, scaling transform. Generate a scale-only transform, based upon
2778     * bucketed scale values. Special case for 'extra raster buckets' - disable filtration in the
2779     * case of an exact match, and isSimple() transform
2780     */
2781    float sx, sy;
2782    transform.decomposeScale(sx, sy);
2783
2784    float bestSx = roundf(fmaxf(1.0f, sx));
2785    float bestSy = roundf(fmaxf(1.0f, sy));
2786    bool filter = true;
2787
2788    for (unsigned int i = 0; i < mCaches.propertyExtraRasterBuckets.size(); i++) {
2789        float bucket = mCaches.propertyExtraRasterBuckets[i];
2790        if (sx == bucket && sy == bucket) {
2791            bestSx = bestSy = bucket;
2792            filter = !transform.isSimple(); // disable filter, if simple
2793            break;
2794        }
2795
2796        if (fabs(bucket - sx) < fabs(bestSx - sx)) bestSx = sx;
2797        if (fabs(bucket - sy) < fabs(bestSy - sy)) bestSy = sy;
2798    }
2799
2800    outMatrix->setScale(bestSx, bestSy);
2801    return filter;
2802}
2803
2804status_t OpenGLRenderer::drawText(const char* text, int bytesCount, int count, float x, float y,
2805        const float* positions, const SkPaint* paint, float totalAdvance, const Rect& bounds,
2806        DrawOpMode drawOpMode) {
2807
2808    if (drawOpMode == kDrawOpMode_Immediate) {
2809        // The checks for corner-case ignorable text and quick rejection is only done for immediate
2810        // drawing as ops from DeferredDisplayList are already filtered for these
2811        if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint) ||
2812                quickRejectSetupScissor(bounds)) {
2813            return DrawGlInfo::kStatusDone;
2814        }
2815    }
2816
2817    const float oldX = x;
2818    const float oldY = y;
2819
2820    const mat4& transform = *currentTransform();
2821    const bool pureTranslate = transform.isPureTranslate();
2822
2823    if (CC_LIKELY(pureTranslate)) {
2824        x = (int) floorf(x + transform.getTranslateX() + 0.5f);
2825        y = (int) floorf(y + transform.getTranslateY() + 0.5f);
2826    }
2827
2828    int alpha;
2829    SkXfermode::Mode mode;
2830    getAlphaAndMode(paint, &alpha, &mode);
2831
2832    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2833
2834    if (CC_UNLIKELY(hasTextShadow(paint))) {
2835        fontRenderer.setFont(paint, SkMatrix::I());
2836        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2837                alpha, oldX, oldY);
2838    }
2839
2840    const bool hasActiveLayer = hasLayer();
2841
2842    // We only pass a partial transform to the font renderer. That partial
2843    // matrix defines how glyphs are rasterized. Typically we want glyphs
2844    // to be rasterized at their final size on screen, which means the partial
2845    // matrix needs to take the scale factor into account.
2846    // When a partial matrix is used to transform glyphs during rasterization,
2847    // the mesh is generated with the inverse transform (in the case of scale,
2848    // the mesh is generated at 1.0 / scale for instance.) This allows us to
2849    // apply the full transform matrix at draw time in the vertex shader.
2850    // Applying the full matrix in the shader is the easiest way to handle
2851    // rotation and perspective and allows us to always generated quads in the
2852    // font renderer which greatly simplifies the code, clipping in particular.
2853    SkMatrix fontTransform;
2854    bool linearFilter = findBestFontTransform(transform, &fontTransform)
2855            || fabs(y - (int) y) > 0.0f
2856            || fabs(x - (int) x) > 0.0f;
2857    fontRenderer.setFont(paint, fontTransform);
2858    fontRenderer.setTextureFiltering(linearFilter);
2859
2860    // TODO: Implement better clipping for scaled/rotated text
2861    const Rect* clip = !pureTranslate ? NULL : currentClipRect();
2862    Rect layerBounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2863
2864    bool status;
2865    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2866
2867    // don't call issuedrawcommand, do it at end of batch
2868    bool forceFinish = (drawOpMode != kDrawOpMode_Defer);
2869    if (CC_UNLIKELY(paint->getTextAlign() != SkPaint::kLeft_Align)) {
2870        SkPaint paintCopy(*paint);
2871        paintCopy.setTextAlign(SkPaint::kLeft_Align);
2872        status = fontRenderer.renderPosText(&paintCopy, clip, text, 0, bytesCount, count, x, y,
2873                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2874    } else {
2875        status = fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2876                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2877    }
2878
2879    if ((status || drawOpMode != kDrawOpMode_Immediate) && hasActiveLayer) {
2880        if (!pureTranslate) {
2881            transform.mapRect(layerBounds);
2882        }
2883        dirtyLayerUnchecked(layerBounds, getRegion());
2884    }
2885
2886    drawTextDecorations(totalAdvance, oldX, oldY, paint);
2887
2888    return DrawGlInfo::kStatusDrew;
2889}
2890
2891status_t OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count,
2892        const SkPath* path, float hOffset, float vOffset, const SkPaint* paint) {
2893    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2894        return DrawGlInfo::kStatusDone;
2895    }
2896
2897    // TODO: avoid scissor by calculating maximum bounds using path bounds + font metrics
2898    mCaches.enableScissor();
2899
2900    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2901    fontRenderer.setFont(paint, SkMatrix::I());
2902    fontRenderer.setTextureFiltering(true);
2903
2904    int alpha;
2905    SkXfermode::Mode mode;
2906    getAlphaAndMode(paint, &alpha, &mode);
2907    TextSetupFunctor functor(this, 0.0f, 0.0f, false, alpha, mode, paint);
2908
2909    const Rect* clip = &mSnapshot->getLocalClip();
2910    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2911
2912    const bool hasActiveLayer = hasLayer();
2913
2914    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2915            hOffset, vOffset, hasActiveLayer ? &bounds : NULL, &functor)) {
2916        if (hasActiveLayer) {
2917            currentTransform()->mapRect(bounds);
2918            dirtyLayerUnchecked(bounds, getRegion());
2919        }
2920    }
2921
2922    return DrawGlInfo::kStatusDrew;
2923}
2924
2925status_t OpenGLRenderer::drawPath(const SkPath* path, const SkPaint* paint) {
2926    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
2927
2928    mCaches.activeTexture(0);
2929
2930    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2931    if (!texture) return DrawGlInfo::kStatusDone;
2932    const AutoTexture autoCleanup(texture);
2933
2934    const float x = texture->left - texture->offset;
2935    const float y = texture->top - texture->offset;
2936
2937    drawPathTexture(texture, x, y, paint);
2938
2939    return DrawGlInfo::kStatusDrew;
2940}
2941
2942status_t OpenGLRenderer::drawLayer(Layer* layer, float x, float y) {
2943    if (!layer) {
2944        return DrawGlInfo::kStatusDone;
2945    }
2946
2947    mat4* transform = NULL;
2948    if (layer->isTextureLayer()) {
2949        transform = &layer->getTransform();
2950        if (!transform->isIdentity()) {
2951            save(SkCanvas::kMatrix_SaveFlag);
2952            concatMatrix(*transform);
2953        }
2954    }
2955
2956    bool clipRequired = false;
2957    const bool rejected = calculateQuickRejectForScissor(x, y,
2958            x + layer->layer.getWidth(), y + layer->layer.getHeight(), &clipRequired, NULL, false);
2959
2960    if (rejected) {
2961        if (transform && !transform->isIdentity()) {
2962            restore();
2963        }
2964        return DrawGlInfo::kStatusDone;
2965    }
2966
2967    updateLayer(layer, true);
2968
2969    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
2970    mCaches.activeTexture(0);
2971
2972    if (CC_LIKELY(!layer->region.isEmpty())) {
2973        if (layer->region.isRect()) {
2974            DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
2975                    composeLayerRect(layer, layer->regionRect));
2976        } else if (layer->mesh) {
2977
2978            const float a = getLayerAlpha(layer);
2979            setupDraw();
2980            setupDrawWithTexture();
2981            setupDrawColor(a, a, a, a);
2982            setupDrawColorFilter(layer->getColorFilter());
2983            setupDrawBlending(layer);
2984            setupDrawProgram();
2985            setupDrawPureColorUniforms();
2986            setupDrawColorFilterUniforms(layer->getColorFilter());
2987            setupDrawTexture(layer->getTexture());
2988            if (CC_LIKELY(currentTransform()->isPureTranslate())) {
2989                int tx = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2990                int ty = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2991
2992                layer->setFilter(GL_NEAREST);
2993                setupDrawModelView(kModelViewMode_Translate, false, tx, ty,
2994                        tx + layer->layer.getWidth(), ty + layer->layer.getHeight(), true);
2995            } else {
2996                layer->setFilter(GL_LINEAR);
2997                setupDrawModelView(kModelViewMode_Translate, false, x, y,
2998                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
2999            }
3000
3001            TextureVertex* mesh = &layer->mesh[0];
3002            GLsizei elementsCount = layer->meshElementCount;
3003
3004            while (elementsCount > 0) {
3005                GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
3006
3007                setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
3008                DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
3009                        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL));
3010
3011                elementsCount -= drawCount;
3012                // Though there are 4 vertices in a quad, we use 6 indices per
3013                // quad to draw with GL_TRIANGLES
3014                mesh += (drawCount / 6) * 4;
3015            }
3016
3017#if DEBUG_LAYERS_AS_REGIONS
3018            drawRegionRectsDebug(layer->region);
3019#endif
3020        }
3021
3022        if (layer->debugDrawUpdate) {
3023            layer->debugDrawUpdate = false;
3024
3025            SkPaint paint;
3026            paint.setColor(0x7f00ff00);
3027            drawColorRect(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight(), &paint);
3028        }
3029    }
3030    layer->hasDrawnSinceUpdate = true;
3031
3032    if (transform && !transform->isIdentity()) {
3033        restore();
3034    }
3035
3036    return DrawGlInfo::kStatusDrew;
3037}
3038
3039///////////////////////////////////////////////////////////////////////////////
3040// Draw filters
3041///////////////////////////////////////////////////////////////////////////////
3042
3043void OpenGLRenderer::resetPaintFilter() {
3044    // when clearing the PaintFilter, the masks should also be cleared for simple DrawModifier
3045    // comparison, see MergingDrawBatch::canMergeWith
3046    mDrawModifiers.mHasDrawFilter = false;
3047    mDrawModifiers.mPaintFilterClearBits = 0;
3048    mDrawModifiers.mPaintFilterSetBits = 0;
3049}
3050
3051void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
3052    mDrawModifiers.mHasDrawFilter = true;
3053    mDrawModifiers.mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
3054    mDrawModifiers.mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
3055}
3056
3057const SkPaint* OpenGLRenderer::filterPaint(const SkPaint* paint) {
3058    if (CC_LIKELY(!mDrawModifiers.mHasDrawFilter || !paint)) {
3059        return paint;
3060    }
3061
3062    uint32_t flags = paint->getFlags();
3063
3064    mFilteredPaint = *paint;
3065    mFilteredPaint.setFlags((flags & ~mDrawModifiers.mPaintFilterClearBits) |
3066            mDrawModifiers.mPaintFilterSetBits);
3067
3068    return &mFilteredPaint;
3069}
3070
3071///////////////////////////////////////////////////////////////////////////////
3072// Drawing implementation
3073///////////////////////////////////////////////////////////////////////////////
3074
3075Texture* OpenGLRenderer::getTexture(const SkBitmap* bitmap) {
3076    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
3077    if (!texture) {
3078        return mCaches.textureCache.get(bitmap);
3079    }
3080    return texture;
3081}
3082
3083void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
3084        float x, float y, const SkPaint* paint) {
3085    if (quickRejectSetupScissor(x, y, x + texture->width, y + texture->height)) {
3086        return;
3087    }
3088
3089    int alpha;
3090    SkXfermode::Mode mode;
3091    getAlphaAndMode(paint, &alpha, &mode);
3092
3093    setupDraw();
3094    setupDrawWithTexture(true);
3095    setupDrawAlpha8Color(paint->getColor(), alpha);
3096    setupDrawColorFilter(getColorFilter(paint));
3097    setupDrawShader(getShader(paint));
3098    setupDrawBlending(paint, true);
3099    setupDrawProgram();
3100    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3101            x, y, x + texture->width, y + texture->height);
3102    setupDrawTexture(texture->id);
3103    setupDrawPureColorUniforms();
3104    setupDrawColorFilterUniforms(getColorFilter(paint));
3105    setupDrawShaderUniforms(getShader(paint));
3106    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
3107
3108    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3109}
3110
3111// Same values used by Skia
3112#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
3113#define kStdUnderline_Offset    (1.0f / 9.0f)
3114#define kStdUnderline_Thickness (1.0f / 18.0f)
3115
3116void OpenGLRenderer::drawTextDecorations(float underlineWidth, float x, float y,
3117        const SkPaint* paint) {
3118    // Handle underline and strike-through
3119    uint32_t flags = paint->getFlags();
3120    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
3121        SkPaint paintCopy(*paint);
3122
3123        if (CC_LIKELY(underlineWidth > 0.0f)) {
3124            const float textSize = paintCopy.getTextSize();
3125            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
3126
3127            const float left = x;
3128            float top = 0.0f;
3129
3130            int linesCount = 0;
3131            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
3132            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
3133
3134            const int pointsCount = 4 * linesCount;
3135            float points[pointsCount];
3136            int currentPoint = 0;
3137
3138            if (flags & SkPaint::kUnderlineText_Flag) {
3139                top = y + textSize * kStdUnderline_Offset;
3140                points[currentPoint++] = left;
3141                points[currentPoint++] = top;
3142                points[currentPoint++] = left + underlineWidth;
3143                points[currentPoint++] = top;
3144            }
3145
3146            if (flags & SkPaint::kStrikeThruText_Flag) {
3147                top = y + textSize * kStdStrikeThru_Offset;
3148                points[currentPoint++] = left;
3149                points[currentPoint++] = top;
3150                points[currentPoint++] = left + underlineWidth;
3151                points[currentPoint++] = top;
3152            }
3153
3154            paintCopy.setStrokeWidth(strokeWidth);
3155
3156            drawLines(&points[0], pointsCount, &paintCopy);
3157        }
3158    }
3159}
3160
3161status_t OpenGLRenderer::drawRects(const float* rects, int count, const SkPaint* paint) {
3162    if (currentSnapshot()->isIgnored()) {
3163        return DrawGlInfo::kStatusDone;
3164    }
3165
3166    return drawColorRects(rects, count, paint, false, true, true);
3167}
3168
3169static void mapPointFakeZ(Vector3& point, const mat4& transformXY, const mat4& transformZ) {
3170    // map z coordinate with true 3d matrix
3171    point.z = transformZ.mapZ(point);
3172
3173    // map x,y coordinates with draw/Skia matrix
3174    transformXY.mapPoint(point.x, point.y);
3175}
3176
3177status_t OpenGLRenderer::drawShadow(float casterAlpha,
3178        const VertexBuffer* ambientShadowVertexBuffer, const VertexBuffer* spotShadowVertexBuffer) {
3179    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
3180
3181    // TODO: use quickRejectWithScissor. For now, always force enable scissor.
3182    mCaches.enableScissor();
3183
3184    SkPaint paint;
3185    paint.setAntiAlias(true); // want to use AlphaVertex
3186
3187    if (ambientShadowVertexBuffer && mAmbientShadowAlpha > 0) {
3188        paint.setARGB(casterAlpha * mAmbientShadowAlpha, 0, 0, 0);
3189        drawVertexBuffer(*ambientShadowVertexBuffer, &paint);
3190    }
3191
3192    if (spotShadowVertexBuffer && mSpotShadowAlpha > 0) {
3193        paint.setARGB(casterAlpha * mSpotShadowAlpha, 0, 0, 0);
3194        drawVertexBuffer(*spotShadowVertexBuffer, &paint);
3195    }
3196
3197    return DrawGlInfo::kStatusDrew;
3198}
3199
3200status_t OpenGLRenderer::drawColorRects(const float* rects, int count, const SkPaint* paint,
3201        bool ignoreTransform, bool dirty, bool clip) {
3202    if (count == 0) {
3203        return DrawGlInfo::kStatusDone;
3204    }
3205
3206    int color = paint->getColor();
3207    // If a shader is set, preserve only the alpha
3208    if (getShader(paint)) {
3209        color |= 0x00ffffff;
3210    }
3211
3212    float left = FLT_MAX;
3213    float top = FLT_MAX;
3214    float right = FLT_MIN;
3215    float bottom = FLT_MIN;
3216
3217    Vertex mesh[count];
3218    Vertex* vertex = mesh;
3219
3220    for (int index = 0; index < count; index += 4) {
3221        float l = rects[index + 0];
3222        float t = rects[index + 1];
3223        float r = rects[index + 2];
3224        float b = rects[index + 3];
3225
3226        Vertex::set(vertex++, l, t);
3227        Vertex::set(vertex++, r, t);
3228        Vertex::set(vertex++, l, b);
3229        Vertex::set(vertex++, r, b);
3230
3231        left = fminf(left, l);
3232        top = fminf(top, t);
3233        right = fmaxf(right, r);
3234        bottom = fmaxf(bottom, b);
3235    }
3236
3237    if (clip && quickRejectSetupScissor(left, top, right, bottom)) {
3238        return DrawGlInfo::kStatusDone;
3239    }
3240
3241    setupDraw();
3242    setupDrawNoTexture();
3243    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3244    setupDrawShader(getShader(paint));
3245    setupDrawColorFilter(getColorFilter(paint));
3246    setupDrawBlending(paint);
3247    setupDrawProgram();
3248    setupDrawDirtyRegionsDisabled();
3249    setupDrawModelView(kModelViewMode_Translate, false,
3250            0.0f, 0.0f, 0.0f, 0.0f, ignoreTransform);
3251    setupDrawColorUniforms(getShader(paint));
3252    setupDrawShaderUniforms(getShader(paint));
3253    setupDrawColorFilterUniforms(getColorFilter(paint));
3254
3255    if (dirty && hasLayer()) {
3256        dirtyLayer(left, top, right, bottom, *currentTransform());
3257    }
3258
3259    issueIndexedQuadDraw(&mesh[0], count / 4);
3260
3261    return DrawGlInfo::kStatusDrew;
3262}
3263
3264void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
3265        const SkPaint* paint, bool ignoreTransform) {
3266    int color = paint->getColor();
3267    // If a shader is set, preserve only the alpha
3268    if (getShader(paint)) {
3269        color |= 0x00ffffff;
3270    }
3271
3272    setupDraw();
3273    setupDrawNoTexture();
3274    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3275    setupDrawShader(getShader(paint));
3276    setupDrawColorFilter(getColorFilter(paint));
3277    setupDrawBlending(paint);
3278    setupDrawProgram();
3279    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3280            left, top, right, bottom, ignoreTransform);
3281    setupDrawColorUniforms(getShader(paint));
3282    setupDrawShaderUniforms(getShader(paint), ignoreTransform);
3283    setupDrawColorFilterUniforms(getColorFilter(paint));
3284    setupDrawSimpleMesh();
3285
3286    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3287}
3288
3289void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
3290        Texture* texture, const SkPaint* paint) {
3291    texture->setWrap(GL_CLAMP_TO_EDGE, true);
3292
3293    GLvoid* vertices = (GLvoid*) NULL;
3294    GLvoid* texCoords = (GLvoid*) gMeshTextureOffset;
3295
3296    if (texture->uvMapper) {
3297        vertices = &mMeshVertices[0].x;
3298        texCoords = &mMeshVertices[0].u;
3299
3300        Rect uvs(0.0f, 0.0f, 1.0f, 1.0f);
3301        texture->uvMapper->map(uvs);
3302
3303        resetDrawTextureTexCoords(uvs.left, uvs.top, uvs.right, uvs.bottom);
3304    }
3305
3306    if (CC_LIKELY(currentTransform()->isPureTranslate())) {
3307        const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
3308        const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
3309
3310        texture->setFilter(GL_NEAREST, true);
3311        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
3312                paint, texture->blend, vertices, texCoords,
3313                GL_TRIANGLE_STRIP, gMeshCount, false, true);
3314    } else {
3315        texture->setFilter(getFilter(paint), true);
3316        drawTextureMesh(left, top, right, bottom, texture->id, paint,
3317                texture->blend, vertices, texCoords, GL_TRIANGLE_STRIP, gMeshCount);
3318    }
3319
3320    if (texture->uvMapper) {
3321        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
3322    }
3323}
3324
3325void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
3326        GLuint texture, const SkPaint* paint, bool blend,
3327        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3328        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3329        ModelViewMode modelViewMode, bool dirty) {
3330
3331    int a;
3332    SkXfermode::Mode mode;
3333    getAlphaAndMode(paint, &a, &mode);
3334    const float alpha = a / 255.0f;
3335
3336    setupDraw();
3337    setupDrawWithTexture();
3338    setupDrawColor(alpha, alpha, alpha, alpha);
3339    setupDrawColorFilter(getColorFilter(paint));
3340    setupDrawBlending(paint, blend, swapSrcDst);
3341    setupDrawProgram();
3342    if (!dirty) setupDrawDirtyRegionsDisabled();
3343    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3344    setupDrawTexture(texture);
3345    setupDrawPureColorUniforms();
3346    setupDrawColorFilterUniforms(getColorFilter(paint));
3347    setupDrawMesh(vertices, texCoords, vbo);
3348
3349    glDrawArrays(drawMode, 0, elementsCount);
3350}
3351
3352void OpenGLRenderer::drawIndexedTextureMesh(float left, float top, float right, float bottom,
3353        GLuint texture, const SkPaint* paint, bool blend,
3354        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3355        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3356        ModelViewMode modelViewMode, bool dirty) {
3357
3358    int a;
3359    SkXfermode::Mode mode;
3360    getAlphaAndMode(paint, &a, &mode);
3361    const float alpha = a / 255.0f;
3362
3363    setupDraw();
3364    setupDrawWithTexture();
3365    setupDrawColor(alpha, alpha, alpha, alpha);
3366    setupDrawColorFilter(getColorFilter(paint));
3367    setupDrawBlending(paint, blend, swapSrcDst);
3368    setupDrawProgram();
3369    if (!dirty) setupDrawDirtyRegionsDisabled();
3370    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3371    setupDrawTexture(texture);
3372    setupDrawPureColorUniforms();
3373    setupDrawColorFilterUniforms(getColorFilter(paint));
3374    setupDrawMeshIndices(vertices, texCoords, vbo);
3375
3376    glDrawElements(drawMode, elementsCount, GL_UNSIGNED_SHORT, NULL);
3377}
3378
3379void OpenGLRenderer::drawAlpha8TextureMesh(float left, float top, float right, float bottom,
3380        GLuint texture, const SkPaint* paint,
3381        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3382        bool ignoreTransform, ModelViewMode modelViewMode, bool dirty) {
3383
3384    int color = paint != NULL ? paint->getColor() : 0;
3385    int alpha;
3386    SkXfermode::Mode mode;
3387    getAlphaAndMode(paint, &alpha, &mode);
3388
3389    setupDraw();
3390    setupDrawWithTexture(true);
3391    if (paint != NULL) {
3392        setupDrawAlpha8Color(color, alpha);
3393    }
3394    setupDrawColorFilter(getColorFilter(paint));
3395    setupDrawShader(getShader(paint));
3396    setupDrawBlending(paint, true);
3397    setupDrawProgram();
3398    if (!dirty) setupDrawDirtyRegionsDisabled();
3399    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3400    setupDrawTexture(texture);
3401    setupDrawPureColorUniforms();
3402    setupDrawColorFilterUniforms(getColorFilter(paint));
3403    setupDrawShaderUniforms(getShader(paint), ignoreTransform);
3404    setupDrawMesh(vertices, texCoords);
3405
3406    glDrawArrays(drawMode, 0, elementsCount);
3407}
3408
3409void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
3410        ProgramDescription& description, bool swapSrcDst) {
3411
3412    if (mSnapshot->roundRectClipState != NULL /*&& !mSkipOutlineClip*/) {
3413        blend = true;
3414        mDescription.hasRoundRectClip = true;
3415    }
3416    mSkipOutlineClip = true;
3417
3418    if (mCountOverdraw) {
3419        if (!mCaches.blend) glEnable(GL_BLEND);
3420        if (mCaches.lastSrcMode != GL_ONE || mCaches.lastDstMode != GL_ONE) {
3421            glBlendFunc(GL_ONE, GL_ONE);
3422        }
3423
3424        mCaches.blend = true;
3425        mCaches.lastSrcMode = GL_ONE;
3426        mCaches.lastDstMode = GL_ONE;
3427
3428        return;
3429    }
3430
3431    blend = blend || mode != SkXfermode::kSrcOver_Mode;
3432
3433    if (blend) {
3434        // These blend modes are not supported by OpenGL directly and have
3435        // to be implemented using shaders. Since the shader will perform
3436        // the blending, turn blending off here
3437        // If the blend mode cannot be implemented using shaders, fall
3438        // back to the default SrcOver blend mode instead
3439        if (CC_UNLIKELY(mode > SkXfermode::kScreen_Mode)) {
3440            if (CC_UNLIKELY(mExtensions.hasFramebufferFetch())) {
3441                description.framebufferMode = mode;
3442                description.swapSrcDst = swapSrcDst;
3443
3444                if (mCaches.blend) {
3445                    glDisable(GL_BLEND);
3446                    mCaches.blend = false;
3447                }
3448
3449                return;
3450            } else {
3451                mode = SkXfermode::kSrcOver_Mode;
3452            }
3453        }
3454
3455        if (!mCaches.blend) {
3456            glEnable(GL_BLEND);
3457        }
3458
3459        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
3460        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
3461
3462        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
3463            glBlendFunc(sourceMode, destMode);
3464            mCaches.lastSrcMode = sourceMode;
3465            mCaches.lastDstMode = destMode;
3466        }
3467    } else if (mCaches.blend) {
3468        glDisable(GL_BLEND);
3469    }
3470    mCaches.blend = blend;
3471}
3472
3473bool OpenGLRenderer::useProgram(Program* program) {
3474    if (!program->isInUse()) {
3475        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
3476        program->use();
3477        mCaches.currentProgram = program;
3478        return false;
3479    }
3480    return true;
3481}
3482
3483void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
3484    TextureVertex* v = &mMeshVertices[0];
3485    TextureVertex::setUV(v++, u1, v1);
3486    TextureVertex::setUV(v++, u2, v1);
3487    TextureVertex::setUV(v++, u1, v2);
3488    TextureVertex::setUV(v++, u2, v2);
3489}
3490
3491void OpenGLRenderer::getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode) const {
3492    getAlphaAndModeDirect(paint, alpha,  mode);
3493    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3494        // if drawing a layer, ignore the paint's alpha
3495        *alpha = mDrawModifiers.mOverrideLayerAlpha * 255;
3496    }
3497    *alpha *= currentSnapshot()->alpha;
3498}
3499
3500float OpenGLRenderer::getLayerAlpha(const Layer* layer) const {
3501    float alpha;
3502    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3503        alpha = mDrawModifiers.mOverrideLayerAlpha;
3504    } else {
3505        alpha = layer->getAlpha() / 255.0f;
3506    }
3507    return alpha * currentSnapshot()->alpha;
3508}
3509
3510}; // namespace uirenderer
3511}; // namespace android
3512