OpenGLRenderer.cpp revision 591be6c7af512a7dbae5a7f0cc9890b82af74e58 
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
48#if DEBUG_DETAILED_EVENTS
49    #define EVENT_LOGD(...) eventMarkDEBUG(__VA_ARGS__)
50#else
51    #define EVENT_LOGD(...)
52#endif
53
54namespace android {
55namespace uirenderer {
56
57static GLenum getFilter(const SkPaint* paint) {
58    if (!paint || paint->getFilterLevel() != SkPaint::kNone_FilterLevel) {
59        return GL_LINEAR;
60    }
61    return GL_NEAREST;
62}
63
64///////////////////////////////////////////////////////////////////////////////
65// Globals
66///////////////////////////////////////////////////////////////////////////////
67
68/**
69 * Structure mapping Skia xfermodes to OpenGL blending factors.
70 */
71struct Blender {
72    SkXfermode::Mode mode;
73    GLenum src;
74    GLenum dst;
75}; // struct Blender
76
77// In this array, the index of each Blender equals the value of the first
78// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
79static const Blender gBlends[] = {
80    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
81    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
82    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
83    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
84    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
85    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
86    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
87    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
88    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
89    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
90    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
91    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
92    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
93    { SkXfermode::kModulate_Mode, GL_ZERO,                GL_SRC_COLOR },
94    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
95};
96
97// This array contains the swapped version of each SkXfermode. For instance
98// this array's SrcOver blending mode is actually DstOver. You can refer to
99// createLayer() for more information on the purpose of this array.
100static const Blender gBlendsSwap[] = {
101    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
102    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
103    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
104    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
105    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
106    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
107    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
108    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
109    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
110    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
111    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
112    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
113    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
114    { SkXfermode::kModulate_Mode, GL_DST_COLOR,           GL_ZERO },
115    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
116};
117
118///////////////////////////////////////////////////////////////////////////////
119// Functions
120///////////////////////////////////////////////////////////////////////////////
121
122template<typename T>
123static inline T min(T a, T b) {
124    return a < b ? a : b;
125}
126
127///////////////////////////////////////////////////////////////////////////////
128// Constructors/destructor
129///////////////////////////////////////////////////////////////////////////////
130
131OpenGLRenderer::OpenGLRenderer(RenderState& renderState)
132        : mFrameStarted(false)
133        , mCaches(Caches::getInstance())
134        , mExtensions(Extensions::getInstance())
135        , mRenderState(renderState)
136        , mScissorOptimizationDisabled(false)
137        , mCountOverdraw(false)
138        , mLightCenter((Vector3){FLT_MIN, FLT_MIN, FLT_MIN})
139        , mLightRadius(FLT_MIN)
140        , mAmbientShadowAlpha(0)
141        , mSpotShadowAlpha(0) {
142    // *set* draw modifiers to be 0
143    memset(&mDrawModifiers, 0, sizeof(mDrawModifiers));
144    mDrawModifiers.mOverrideLayerAlpha = 1.0f;
145
146    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
147}
148
149OpenGLRenderer::~OpenGLRenderer() {
150    // The context has already been destroyed at this point, do not call
151    // GL APIs. All GL state should be kept in Caches.h
152}
153
154void OpenGLRenderer::initProperties() {
155    char property[PROPERTY_VALUE_MAX];
156    if (property_get(PROPERTY_DISABLE_SCISSOR_OPTIMIZATION, property, "false")) {
157        mScissorOptimizationDisabled = !strcasecmp(property, "true");
158        INIT_LOGD("  Scissor optimization %s",
159                mScissorOptimizationDisabled ? "disabled" : "enabled");
160    } else {
161        INIT_LOGD("  Scissor optimization enabled");
162    }
163}
164
165void OpenGLRenderer::initLight(const Vector3& lightCenter, float lightRadius,
166        uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha) {
167    mLightCenter = lightCenter;
168    mLightRadius = lightRadius;
169    mAmbientShadowAlpha = ambientShadowAlpha;
170    mSpotShadowAlpha = spotShadowAlpha;
171}
172
173///////////////////////////////////////////////////////////////////////////////
174// Setup
175///////////////////////////////////////////////////////////////////////////////
176
177void OpenGLRenderer::onViewportInitialized() {
178    glDisable(GL_DITHER);
179    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
180
181    glEnableVertexAttribArray(Program::kBindingPosition);
182}
183
184void OpenGLRenderer::setupFrameState(float left, float top,
185        float right, float bottom, bool opaque) {
186    mCaches.clearGarbage();
187    initializeSaveStack(left, top, right, bottom, mLightCenter);
188    mOpaque = opaque;
189    mTilingClip.set(left, top, right, bottom);
190}
191
192status_t OpenGLRenderer::startFrame() {
193    if (mFrameStarted) return DrawGlInfo::kStatusDone;
194    mFrameStarted = true;
195
196    mDirtyClip = true;
197
198    discardFramebuffer(mTilingClip.left, mTilingClip.top, mTilingClip.right, mTilingClip.bottom);
199
200    mRenderState.setViewport(getWidth(), getHeight());
201
202    // Functors break the tiling extension in pretty spectacular ways
203    // This ensures we don't use tiling when a functor is going to be
204    // invoked during the frame
205    mSuppressTiling = mCaches.hasRegisteredFunctors();
206
207    startTilingCurrentClip(true);
208
209    debugOverdraw(true, true);
210
211    return clear(mTilingClip.left, mTilingClip.top,
212            mTilingClip.right, mTilingClip.bottom, mOpaque);
213}
214
215status_t OpenGLRenderer::prepareDirty(float left, float top,
216        float right, float bottom, bool opaque) {
217
218    setupFrameState(left, top, right, bottom, opaque);
219
220    // Layer renderers will start the frame immediately
221    // The framebuffer renderer will first defer the display list
222    // for each layer and wait until the first drawing command
223    // to start the frame
224    if (currentSnapshot()->fbo == 0) {
225        syncState();
226        updateLayers();
227    } else {
228        return startFrame();
229    }
230
231    return DrawGlInfo::kStatusDone;
232}
233
234void OpenGLRenderer::discardFramebuffer(float left, float top, float right, float bottom) {
235    // If we know that we are going to redraw the entire framebuffer,
236    // perform a discard to let the driver know we don't need to preserve
237    // the back buffer for this frame.
238    if (mExtensions.hasDiscardFramebuffer() &&
239            left <= 0.0f && top <= 0.0f && right >= getWidth() && bottom >= getHeight()) {
240        const bool isFbo = getTargetFbo() == 0;
241        const GLenum attachments[] = {
242                isFbo ? (const GLenum) GL_COLOR_EXT : (const GLenum) GL_COLOR_ATTACHMENT0,
243                isFbo ? (const GLenum) GL_STENCIL_EXT : (const GLenum) GL_STENCIL_ATTACHMENT };
244        glDiscardFramebufferEXT(GL_FRAMEBUFFER, 1, attachments);
245    }
246}
247
248status_t OpenGLRenderer::clear(float left, float top, float right, float bottom, bool opaque) {
249    if (!opaque || mCountOverdraw) {
250        mCaches.enableScissor();
251        mCaches.setScissor(left, getViewportHeight() - bottom, right - left, bottom - top);
252        glClear(GL_COLOR_BUFFER_BIT);
253        return DrawGlInfo::kStatusDrew;
254    }
255
256    mCaches.resetScissor();
257    return DrawGlInfo::kStatusDone;
258}
259
260void OpenGLRenderer::syncState() {
261    if (mCaches.blend) {
262        glEnable(GL_BLEND);
263    } else {
264        glDisable(GL_BLEND);
265    }
266}
267
268void OpenGLRenderer::startTilingCurrentClip(bool opaque, bool expand) {
269    if (!mSuppressTiling) {
270        const Snapshot* snapshot = currentSnapshot();
271
272        const Rect* clip = &mTilingClip;
273        if (snapshot->flags & Snapshot::kFlagFboTarget) {
274            clip = &(snapshot->layer->clipRect);
275        }
276
277        startTiling(*clip, getViewportHeight(), opaque, expand);
278    }
279}
280
281void OpenGLRenderer::startTiling(const Rect& clip, int windowHeight, bool opaque, bool expand) {
282    if (!mSuppressTiling) {
283        if(expand) {
284            // Expand the startTiling region by 1
285            int leftNotZero = (clip.left > 0) ? 1 : 0;
286            int topNotZero = (windowHeight - clip.bottom > 0) ? 1 : 0;
287
288            mCaches.startTiling(
289                clip.left - leftNotZero,
290                windowHeight - clip.bottom - topNotZero,
291                clip.right - clip.left + leftNotZero + 1,
292                clip.bottom - clip.top + topNotZero + 1,
293                opaque);
294        } else {
295            mCaches.startTiling(clip.left, windowHeight - clip.bottom,
296                clip.right - clip.left, clip.bottom - clip.top, opaque);
297        }
298    }
299}
300
301void OpenGLRenderer::endTiling() {
302    if (!mSuppressTiling) mCaches.endTiling();
303}
304
305void OpenGLRenderer::finish() {
306    renderOverdraw();
307    endTiling();
308
309    // When finish() is invoked on FBO 0 we've reached the end
310    // of the current frame
311    if (getTargetFbo() == 0) {
312        mCaches.pathCache.trim();
313        mCaches.tessellationCache.trim();
314    }
315
316    if (!suppressErrorChecks()) {
317#if DEBUG_OPENGL
318        GLUtils::dumpGLErrors();
319#endif
320
321#if DEBUG_MEMORY_USAGE
322        mCaches.dumpMemoryUsage();
323#else
324        if (mCaches.getDebugLevel() & kDebugMemory) {
325            mCaches.dumpMemoryUsage();
326        }
327#endif
328    }
329
330    if (mCountOverdraw) {
331        countOverdraw();
332    }
333
334    mFrameStarted = false;
335}
336
337void OpenGLRenderer::resumeAfterLayer() {
338    mRenderState.setViewport(getViewportWidth(), getViewportHeight());
339    mRenderState.bindFramebuffer(currentSnapshot()->fbo);
340    debugOverdraw(true, false);
341
342    mCaches.resetScissor();
343    dirtyClip();
344}
345
346status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
347    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
348
349    Rect clip(*currentClipRect());
350    clip.snapToPixelBoundaries();
351
352    // Since we don't know what the functor will draw, let's dirty
353    // the entire clip region
354    if (hasLayer()) {
355        dirtyLayerUnchecked(clip, getRegion());
356    }
357
358    DrawGlInfo info;
359    info.clipLeft = clip.left;
360    info.clipTop = clip.top;
361    info.clipRight = clip.right;
362    info.clipBottom = clip.bottom;
363    info.isLayer = hasLayer();
364    info.width = getViewportWidth();
365    info.height = getViewportHeight();
366    currentTransform()->copyTo(&info.transform[0]);
367
368    bool prevDirtyClip = mDirtyClip;
369    // setup GL state for functor
370    if (mDirtyClip) {
371        setStencilFromClip(); // can issue draws, so must precede enableScissor()/interrupt()
372    }
373    if (mCaches.enableScissor() || prevDirtyClip) {
374        setScissorFromClip();
375    }
376
377    mRenderState.invokeFunctor(functor, DrawGlInfo::kModeDraw, &info);
378    // Scissor may have been modified, reset dirty clip
379    dirtyClip();
380
381    return DrawGlInfo::kStatusDrew;
382}
383
384///////////////////////////////////////////////////////////////////////////////
385// Debug
386///////////////////////////////////////////////////////////////////////////////
387
388void OpenGLRenderer::eventMarkDEBUG(const char* fmt, ...) const {
389#if DEBUG_DETAILED_EVENTS
390    const int BUFFER_SIZE = 256;
391    va_list ap;
392    char buf[BUFFER_SIZE];
393
394    va_start(ap, fmt);
395    vsnprintf(buf, BUFFER_SIZE, fmt, ap);
396    va_end(ap);
397
398    eventMark(buf);
399#endif
400}
401
402
403void OpenGLRenderer::eventMark(const char* name) const {
404    mCaches.eventMark(0, name);
405}
406
407void OpenGLRenderer::startMark(const char* name) const {
408    mCaches.startMark(0, name);
409}
410
411void OpenGLRenderer::endMark() const {
412    mCaches.endMark();
413}
414
415void OpenGLRenderer::debugOverdraw(bool enable, bool clear) {
416    mRenderState.debugOverdraw(enable, clear);
417}
418
419void OpenGLRenderer::renderOverdraw() {
420    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
421        const Rect* clip = &mTilingClip;
422
423        mCaches.enableScissor();
424        mCaches.setScissor(clip->left, firstSnapshot()->getViewportHeight() - clip->bottom,
425                clip->right - clip->left, clip->bottom - clip->top);
426
427        // 1x overdraw
428        mCaches.stencil.enableDebugTest(2);
429        drawColor(mCaches.getOverdrawColor(1), SkXfermode::kSrcOver_Mode);
430
431        // 2x overdraw
432        mCaches.stencil.enableDebugTest(3);
433        drawColor(mCaches.getOverdrawColor(2), SkXfermode::kSrcOver_Mode);
434
435        // 3x overdraw
436        mCaches.stencil.enableDebugTest(4);
437        drawColor(mCaches.getOverdrawColor(3), SkXfermode::kSrcOver_Mode);
438
439        // 4x overdraw and higher
440        mCaches.stencil.enableDebugTest(4, true);
441        drawColor(mCaches.getOverdrawColor(4), SkXfermode::kSrcOver_Mode);
442
443        mCaches.stencil.disable();
444    }
445}
446
447void OpenGLRenderer::countOverdraw() {
448    size_t count = getWidth() * getHeight();
449    uint32_t* buffer = new uint32_t[count];
450    glReadPixels(0, 0, getWidth(), getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, &buffer[0]);
451
452    size_t total = 0;
453    for (size_t i = 0; i < count; i++) {
454        total += buffer[i] & 0xff;
455    }
456
457    mOverdraw = total / float(count);
458
459    delete[] buffer;
460}
461
462///////////////////////////////////////////////////////////////////////////////
463// Layers
464///////////////////////////////////////////////////////////////////////////////
465
466bool OpenGLRenderer::updateLayer(Layer* layer, bool inFrame) {
467    if (layer->deferredUpdateScheduled && layer->renderer
468            && layer->renderNode.get() && layer->renderNode->isRenderable()) {
469        ATRACE_CALL();
470
471        Rect& dirty = layer->dirtyRect;
472
473        if (inFrame) {
474            endTiling();
475            debugOverdraw(false, false);
476        }
477
478        if (CC_UNLIKELY(inFrame || mCaches.drawDeferDisabled)) {
479            layer->render(*this);
480        } else {
481            layer->defer(*this);
482        }
483
484        if (inFrame) {
485            resumeAfterLayer();
486            startTilingCurrentClip();
487        }
488
489        layer->debugDrawUpdate = mCaches.debugLayersUpdates;
490        layer->hasDrawnSinceUpdate = false;
491
492        return true;
493    }
494
495    return false;
496}
497
498void OpenGLRenderer::updateLayers() {
499    // If draw deferring is enabled this method will simply defer
500    // the display list of each individual layer. The layers remain
501    // in the layer updates list which will be cleared by flushLayers().
502    int count = mLayerUpdates.size();
503    if (count > 0) {
504        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
505            startMark("Layer Updates");
506        } else {
507            startMark("Defer Layer Updates");
508        }
509
510        // Note: it is very important to update the layers in order
511        for (int i = 0; i < count; i++) {
512            Layer* layer = mLayerUpdates.itemAt(i);
513            updateLayer(layer, false);
514            if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
515                mCaches.resourceCache.decrementRefcount(layer);
516            }
517        }
518
519        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
520            mLayerUpdates.clear();
521            mRenderState.bindFramebuffer(getTargetFbo());
522        }
523        endMark();
524    }
525}
526
527void OpenGLRenderer::flushLayers() {
528    int count = mLayerUpdates.size();
529    if (count > 0) {
530        startMark("Apply Layer Updates");
531        char layerName[12];
532
533        // Note: it is very important to update the layers in order
534        for (int i = 0; i < count; i++) {
535            sprintf(layerName, "Layer #%d", i);
536            startMark(layerName);
537
538            ATRACE_BEGIN("flushLayer");
539            Layer* layer = mLayerUpdates.itemAt(i);
540            layer->flush();
541            ATRACE_END();
542
543            mCaches.resourceCache.decrementRefcount(layer);
544
545            endMark();
546        }
547
548        mLayerUpdates.clear();
549        mRenderState.bindFramebuffer(getTargetFbo());
550
551        endMark();
552    }
553}
554
555void OpenGLRenderer::pushLayerUpdate(Layer* layer) {
556    if (layer) {
557        // Make sure we don't introduce duplicates.
558        // SortedVector would do this automatically but we need to respect
559        // the insertion order. The linear search is not an issue since
560        // this list is usually very short (typically one item, at most a few)
561        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
562            if (mLayerUpdates.itemAt(i) == layer) {
563                return;
564            }
565        }
566        mLayerUpdates.push_back(layer);
567        mCaches.resourceCache.incrementRefcount(layer);
568    }
569}
570
571void OpenGLRenderer::cancelLayerUpdate(Layer* layer) {
572    if (layer) {
573        for (int i = mLayerUpdates.size() - 1; i >= 0; i--) {
574            if (mLayerUpdates.itemAt(i) == layer) {
575                mLayerUpdates.removeAt(i);
576                mCaches.resourceCache.decrementRefcount(layer);
577                break;
578            }
579        }
580    }
581}
582
583void OpenGLRenderer::clearLayerUpdates() {
584    size_t count = mLayerUpdates.size();
585    if (count > 0) {
586        mCaches.resourceCache.lock();
587        for (size_t i = 0; i < count; i++) {
588            mCaches.resourceCache.decrementRefcountLocked(mLayerUpdates.itemAt(i));
589        }
590        mCaches.resourceCache.unlock();
591        mLayerUpdates.clear();
592    }
593}
594
595void OpenGLRenderer::flushLayerUpdates() {
596    ATRACE_CALL();
597    syncState();
598    updateLayers();
599    flushLayers();
600    // Wait for all the layer updates to be executed
601    AutoFence fence;
602}
603
604void OpenGLRenderer::markLayersAsBuildLayers() {
605    for (size_t i = 0; i < mLayerUpdates.size(); i++) {
606        mLayerUpdates[i]->wasBuildLayered = true;
607    }
608}
609
610///////////////////////////////////////////////////////////////////////////////
611// State management
612///////////////////////////////////////////////////////////////////////////////
613
614void OpenGLRenderer::onSnapshotRestored(const Snapshot& removed, const Snapshot& restored) {
615    bool restoreViewport = removed.flags & Snapshot::kFlagIsFboLayer;
616    bool restoreClip = removed.flags & Snapshot::kFlagClipSet;
617    bool restoreLayer = removed.flags & Snapshot::kFlagIsLayer;
618
619    if (restoreViewport) {
620        mRenderState.setViewport(getViewportWidth(), getViewportHeight());
621    }
622
623    if (restoreClip) {
624        dirtyClip();
625    }
626
627    if (restoreLayer) {
628        endMark(); // Savelayer
629        startMark("ComposeLayer");
630        composeLayer(removed, restored);
631        endMark();
632    }
633}
634
635///////////////////////////////////////////////////////////////////////////////
636// Layers
637///////////////////////////////////////////////////////////////////////////////
638
639int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
640        const SkPaint* paint, int flags, const SkPath* convexMask) {
641    const int count = saveSnapshot(flags);
642
643    if (!currentSnapshot()->isIgnored()) {
644        createLayer(left, top, right, bottom, paint, flags, convexMask);
645    }
646
647    return count;
648}
649
650void OpenGLRenderer::calculateLayerBoundsAndClip(Rect& bounds, Rect& clip, bool fboLayer) {
651    const Rect untransformedBounds(bounds);
652
653    currentTransform()->mapRect(bounds);
654
655    // Layers only make sense if they are in the framebuffer's bounds
656    if (bounds.intersect(*currentClipRect())) {
657        // We cannot work with sub-pixels in this case
658        bounds.snapToPixelBoundaries();
659
660        // When the layer is not an FBO, we may use glCopyTexImage so we
661        // need to make sure the layer does not extend outside the bounds
662        // of the framebuffer
663        const Snapshot& previous = *(currentSnapshot()->previous);
664        Rect previousViewport(0, 0, previous.getViewportWidth(), previous.getViewportHeight());
665        if (!bounds.intersect(previousViewport)) {
666            bounds.setEmpty();
667        } else if (fboLayer) {
668            clip.set(bounds);
669            mat4 inverse;
670            inverse.loadInverse(*currentTransform());
671            inverse.mapRect(clip);
672            clip.snapToPixelBoundaries();
673            if (clip.intersect(untransformedBounds)) {
674                clip.translate(-untransformedBounds.left, -untransformedBounds.top);
675                bounds.set(untransformedBounds);
676            } else {
677                clip.setEmpty();
678            }
679        }
680    } else {
681        bounds.setEmpty();
682    }
683}
684
685void OpenGLRenderer::updateSnapshotIgnoreForLayer(const Rect& bounds, const Rect& clip,
686        bool fboLayer, int alpha) {
687    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
688            bounds.getHeight() > mCaches.maxTextureSize ||
689            (fboLayer && clip.isEmpty())) {
690        mSnapshot->empty = fboLayer;
691    } else {
692        mSnapshot->invisible = mSnapshot->invisible || (alpha <= 0 && fboLayer);
693    }
694}
695
696int OpenGLRenderer::saveLayerDeferred(float left, float top, float right, float bottom,
697        const SkPaint* paint, int flags) {
698    const int count = saveSnapshot(flags);
699
700    if (!currentSnapshot()->isIgnored() && (flags & SkCanvas::kClipToLayer_SaveFlag)) {
701        // initialize the snapshot as though it almost represents an FBO layer so deferred draw
702        // operations will be able to store and restore the current clip and transform info, and
703        // quick rejection will be correct (for display lists)
704
705        Rect bounds(left, top, right, bottom);
706        Rect clip;
707        calculateLayerBoundsAndClip(bounds, clip, true);
708        updateSnapshotIgnoreForLayer(bounds, clip, true, getAlphaDirect(paint));
709
710        if (!currentSnapshot()->isIgnored()) {
711            mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
712            mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
713            mSnapshot->initializeViewport(bounds.getWidth(), bounds.getHeight());
714            mSnapshot->roundRectClipState = NULL;
715        }
716    }
717
718    return count;
719}
720
721/**
722 * Layers are viewed by Skia are slightly different than layers in image editing
723 * programs (for instance.) When a layer is created, previously created layers
724 * and the frame buffer still receive every drawing command. For instance, if a
725 * layer is created and a shape intersecting the bounds of the layers and the
726 * framebuffer is draw, the shape will be drawn on both (unless the layer was
727 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
728 *
729 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
730 * texture. Unfortunately, this is inefficient as it requires every primitive to
731 * be drawn n + 1 times, where n is the number of active layers. In practice this
732 * means, for every primitive:
733 *   - Switch active frame buffer
734 *   - Change viewport, clip and projection matrix
735 *   - Issue the drawing
736 *
737 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
738 * To avoid this, layers are implemented in a different way here, at least in the
739 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
740 * is set. When this flag is set we can redirect all drawing operations into a
741 * single FBO.
742 *
743 * This implementation relies on the frame buffer being at least RGBA 8888. When
744 * a layer is created, only a texture is created, not an FBO. The content of the
745 * frame buffer contained within the layer's bounds is copied into this texture
746 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
747 * buffer and drawing continues as normal. This technique therefore treats the
748 * frame buffer as a scratch buffer for the layers.
749 *
750 * To compose the layers back onto the frame buffer, each layer texture
751 * (containing the original frame buffer data) is drawn as a simple quad over
752 * the frame buffer. The trick is that the quad is set as the composition
753 * destination in the blending equation, and the frame buffer becomes the source
754 * of the composition.
755 *
756 * Drawing layers with an alpha value requires an extra step before composition.
757 * An empty quad is drawn over the layer's region in the frame buffer. This quad
758 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
759 * quad is used to multiply the colors in the frame buffer. This is achieved by
760 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
761 * GL_ZERO, GL_SRC_ALPHA.
762 *
763 * Because glCopyTexImage2D() can be slow, an alternative implementation might
764 * be use to draw a single clipped layer. The implementation described above
765 * is correct in every case.
766 *
767 * (1) The frame buffer is actually not cleared right away. To allow the GPU
768 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
769 *     buffer is left untouched until the first drawing operation. Only when
770 *     something actually gets drawn are the layers regions cleared.
771 */
772bool OpenGLRenderer::createLayer(float left, float top, float right, float bottom,
773        const SkPaint* paint, int flags, const SkPath* convexMask) {
774    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
775    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
776
777    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
778
779    // Window coordinates of the layer
780    Rect clip;
781    Rect bounds(left, top, right, bottom);
782    calculateLayerBoundsAndClip(bounds, clip, fboLayer);
783    updateSnapshotIgnoreForLayer(bounds, clip, fboLayer, getAlphaDirect(paint));
784
785    // Bail out if we won't draw in this snapshot
786    if (currentSnapshot()->isIgnored()) {
787        return false;
788    }
789
790    mCaches.activeTexture(0);
791    Layer* layer = mCaches.layerCache.get(mRenderState, bounds.getWidth(), bounds.getHeight());
792    if (!layer) {
793        return false;
794    }
795
796    layer->setPaint(paint);
797    layer->layer.set(bounds);
798    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
799            bounds.getWidth() / float(layer->getWidth()), 0.0f);
800
801    layer->setBlend(true);
802    layer->setDirty(false);
803    layer->setConvexMask(convexMask); // note: the mask must be cleared before returning to the cache
804
805    // Save the layer in the snapshot
806    mSnapshot->flags |= Snapshot::kFlagIsLayer;
807    mSnapshot->layer = layer;
808
809    startMark("SaveLayer");
810    if (fboLayer) {
811        return createFboLayer(layer, bounds, clip);
812    } else {
813        // Copy the framebuffer into the layer
814        layer->bindTexture();
815        if (!bounds.isEmpty()) {
816            if (layer->isEmpty()) {
817                // Workaround for some GL drivers. When reading pixels lying outside
818                // of the window we should get undefined values for those pixels.
819                // Unfortunately some drivers will turn the entire target texture black
820                // when reading outside of the window.
821                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->getWidth(), layer->getHeight(),
822                        0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
823                layer->setEmpty(false);
824            }
825
826            glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
827                    bounds.left, getViewportHeight() - bounds.bottom,
828                    bounds.getWidth(), bounds.getHeight());
829
830            // Enqueue the buffer coordinates to clear the corresponding region later
831            mLayers.push(new Rect(bounds));
832        }
833    }
834
835    return true;
836}
837
838bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, Rect& clip) {
839    layer->clipRect.set(clip);
840    layer->setFbo(mCaches.fboCache.get());
841
842    mSnapshot->region = &mSnapshot->layer->region;
843    mSnapshot->flags |= Snapshot::kFlagFboTarget | Snapshot::kFlagIsFboLayer;
844    mSnapshot->fbo = layer->getFbo();
845    mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
846    mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
847    mSnapshot->initializeViewport(bounds.getWidth(), bounds.getHeight());
848    mSnapshot->roundRectClipState = NULL;
849
850    endTiling();
851    debugOverdraw(false, false);
852    // Bind texture to FBO
853    mRenderState.bindFramebuffer(layer->getFbo());
854    layer->bindTexture();
855
856    // Initialize the texture if needed
857    if (layer->isEmpty()) {
858        layer->allocateTexture();
859        layer->setEmpty(false);
860    }
861
862    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
863            layer->getTexture(), 0);
864
865    // Expand the startTiling region by 1
866    startTilingCurrentClip(true, true);
867
868    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
869    mCaches.enableScissor();
870    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
871            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
872    glClear(GL_COLOR_BUFFER_BIT);
873
874    dirtyClip();
875
876    // Change the ortho projection
877    mRenderState.setViewport(bounds.getWidth(), bounds.getHeight());
878    return true;
879}
880
881/**
882 * Read the documentation of createLayer() before doing anything in this method.
883 */
884void OpenGLRenderer::composeLayer(const Snapshot& removed, const Snapshot& restored) {
885    if (!removed.layer) {
886        ALOGE("Attempting to compose a layer that does not exist");
887        return;
888    }
889
890    Layer* layer = removed.layer;
891    const Rect& rect = layer->layer;
892    const bool fboLayer = removed.flags & Snapshot::kFlagIsFboLayer;
893
894    bool clipRequired = false;
895    calculateQuickRejectForScissor(rect.left, rect.top, rect.right, rect.bottom,
896            &clipRequired, NULL, false); // safely ignore return, should never be rejected
897    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
898
899    if (fboLayer) {
900        endTiling();
901
902        // Detach the texture from the FBO
903        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
904
905        layer->removeFbo(false);
906
907        // Unbind current FBO and restore previous one
908        mRenderState.bindFramebuffer(restored.fbo);
909        debugOverdraw(true, false);
910
911        startTilingCurrentClip();
912    }
913
914    if (!fboLayer && layer->getAlpha() < 255) {
915        SkPaint layerPaint;
916        layerPaint.setAlpha(layer->getAlpha());
917        layerPaint.setXfermodeMode(SkXfermode::kDstIn_Mode);
918        layerPaint.setColorFilter(layer->getColorFilter());
919
920        drawColorRect(rect.left, rect.top, rect.right, rect.bottom, &layerPaint, true);
921        // Required below, composeLayerRect() will divide by 255
922        layer->setAlpha(255);
923    }
924
925    mCaches.unbindMeshBuffer();
926
927    mCaches.activeTexture(0);
928
929    // When the layer is stored in an FBO, we can save a bit of fillrate by
930    // drawing only the dirty region
931    if (fboLayer) {
932        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *restored.transform);
933        composeLayerRegion(layer, rect);
934    } else if (!rect.isEmpty()) {
935        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
936
937        save(0);
938        // the layer contains screen buffer content that shouldn't be alpha modulated
939        // (and any necessary alpha modulation was handled drawing into the layer)
940        mSnapshot->alpha = 1.0f;
941        composeLayerRect(layer, rect, true);
942        restore();
943    }
944
945    dirtyClip();
946
947    // Failing to add the layer to the cache should happen only if the layer is too large
948    layer->setConvexMask(NULL);
949    if (!mCaches.layerCache.put(layer)) {
950        LAYER_LOGD("Deleting layer");
951        Caches::getInstance().resourceCache.decrementRefcount(layer);
952    }
953}
954
955void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
956    float alpha = getLayerAlpha(layer);
957
958    setupDraw();
959    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
960        setupDrawWithTexture();
961    } else {
962        setupDrawWithExternalTexture();
963    }
964    setupDrawTextureTransform();
965    setupDrawColor(alpha, alpha, alpha, alpha);
966    setupDrawColorFilter(layer->getColorFilter());
967    setupDrawBlending(layer);
968    setupDrawProgram();
969    setupDrawPureColorUniforms();
970    setupDrawColorFilterUniforms(layer->getColorFilter());
971    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
972        setupDrawTexture(layer->getTexture());
973    } else {
974        setupDrawExternalTexture(layer->getTexture());
975    }
976    if (currentTransform()->isPureTranslate() &&
977            !layer->getForceFilter() &&
978            layer->getWidth() == (uint32_t) rect.getWidth() &&
979            layer->getHeight() == (uint32_t) rect.getHeight()) {
980        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
981        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
982
983        layer->setFilter(GL_NEAREST);
984        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
985                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
986    } else {
987        layer->setFilter(GL_LINEAR);
988        setupDrawModelView(kModelViewMode_TranslateAndScale, false,
989                rect.left, rect.top, rect.right, rect.bottom);
990    }
991    setupDrawTextureTransformUniforms(layer->getTexTransform());
992    setupDrawMesh(&mMeshVertices[0].x, &mMeshVertices[0].u);
993
994    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
995}
996
997void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
998    if (layer->isTextureLayer()) {
999        EVENT_LOGD("composeTextureLayerRect");
1000        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
1001        drawTextureLayer(layer, rect);
1002        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1003    } else {
1004        EVENT_LOGD("composeHardwareLayerRect");
1005        const Rect& texCoords = layer->texCoords;
1006        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
1007                texCoords.right, texCoords.bottom);
1008
1009        float x = rect.left;
1010        float y = rect.top;
1011        bool simpleTransform = currentTransform()->isPureTranslate() &&
1012                layer->getWidth() == (uint32_t) rect.getWidth() &&
1013                layer->getHeight() == (uint32_t) rect.getHeight();
1014
1015        if (simpleTransform) {
1016            // When we're swapping, the layer is already in screen coordinates
1017            if (!swap) {
1018                x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
1019                y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
1020            }
1021
1022            layer->setFilter(GL_NEAREST, true);
1023        } else {
1024            layer->setFilter(GL_LINEAR, true);
1025        }
1026
1027        SkPaint layerPaint;
1028        layerPaint.setAlpha(getLayerAlpha(layer) * 255);
1029        layerPaint.setXfermodeMode(layer->getMode());
1030        layerPaint.setColorFilter(layer->getColorFilter());
1031
1032        bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f;
1033        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
1034                layer->getTexture(), &layerPaint, blend,
1035                &mMeshVertices[0].x, &mMeshVertices[0].u,
1036                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
1037
1038        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1039    }
1040}
1041
1042/**
1043 * Issues the command X, and if we're composing a save layer to the fbo or drawing a newly updated
1044 * hardware layer with overdraw debug on, draws again to the stencil only, so that these draw
1045 * operations are correctly counted twice for overdraw. NOTE: assumes composeLayerRegion only used
1046 * by saveLayer's restore
1047 */
1048#define DRAW_DOUBLE_STENCIL_IF(COND, DRAW_COMMAND) {                             \
1049        DRAW_COMMAND;                                                            \
1050        if (CC_UNLIKELY(mCaches.debugOverdraw && getTargetFbo() == 0 && COND)) { \
1051            glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);                 \
1052            DRAW_COMMAND;                                                        \
1053            glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);                     \
1054        }                                                                        \
1055    }
1056
1057#define DRAW_DOUBLE_STENCIL(DRAW_COMMAND) DRAW_DOUBLE_STENCIL_IF(true, DRAW_COMMAND)
1058
1059// This class is purely for inspection. It inherits from SkShader, but Skia does not know how to
1060// use it. The OpenGLRenderer will look at it to find its Layer and whether it is opaque.
1061class LayerShader : public SkShader {
1062public:
1063    LayerShader(Layer* layer, const SkMatrix* localMatrix)
1064    : INHERITED(localMatrix)
1065    , mLayer(layer) {
1066    }
1067
1068    virtual bool asACustomShader(void** data) const {
1069        if (data) {
1070            *data = static_cast<void*>(mLayer);
1071        }
1072        return true;
1073    }
1074
1075    virtual bool isOpaque() const {
1076        return !mLayer->isBlend();
1077    }
1078
1079protected:
1080    virtual void shadeSpan(int x, int y, SkPMColor[], int count) {
1081        LOG_ALWAYS_FATAL("LayerShader should never be drawn with raster backend.");
1082    }
1083
1084    virtual void flatten(SkWriteBuffer&) const {
1085        LOG_ALWAYS_FATAL("LayerShader should never be flattened.");
1086    }
1087
1088    virtual Factory getFactory() const {
1089        LOG_ALWAYS_FATAL("LayerShader should never be created from a stream.");
1090        return NULL;
1091    }
1092private:
1093    // Unowned.
1094    Layer* mLayer;
1095    typedef SkShader INHERITED;
1096};
1097
1098void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
1099    if (CC_UNLIKELY(layer->region.isEmpty())) return; // nothing to draw
1100
1101    if (layer->getConvexMask()) {
1102        save(SkCanvas::kClip_SaveFlag | SkCanvas::kMatrix_SaveFlag);
1103
1104        // clip to the area of the layer the mask can be larger
1105        clipRect(rect.left, rect.top, rect.right, rect.bottom, SkRegion::kIntersect_Op);
1106
1107        SkPaint paint;
1108        paint.setAntiAlias(true);
1109        paint.setColor(SkColorSetARGB(int(getLayerAlpha(layer) * 255), 0, 0, 0));
1110
1111        // create LayerShader to map SaveLayer content into subsequent draw
1112        SkMatrix shaderMatrix;
1113        shaderMatrix.setTranslate(rect.left, rect.bottom);
1114        shaderMatrix.preScale(1, -1);
1115        LayerShader layerShader(layer, &shaderMatrix);
1116        paint.setShader(&layerShader);
1117
1118        // Since the drawing primitive is defined in local drawing space,
1119        // we don't need to modify the draw matrix
1120        const SkPath* maskPath = layer->getConvexMask();
1121        DRAW_DOUBLE_STENCIL(drawConvexPath(*maskPath, &paint));
1122
1123        paint.setShader(NULL);
1124        restore();
1125
1126        return;
1127    }
1128
1129    if (layer->region.isRect()) {
1130        layer->setRegionAsRect();
1131
1132        DRAW_DOUBLE_STENCIL(composeLayerRect(layer, layer->regionRect));
1133
1134        layer->region.clear();
1135        return;
1136    }
1137
1138    EVENT_LOGD("composeLayerRegion");
1139    // standard Region based draw
1140    size_t count;
1141    const android::Rect* rects;
1142    Region safeRegion;
1143    if (CC_LIKELY(hasRectToRectTransform())) {
1144        rects = layer->region.getArray(&count);
1145    } else {
1146        safeRegion = Region::createTJunctionFreeRegion(layer->region);
1147        rects = safeRegion.getArray(&count);
1148    }
1149
1150    const float alpha = getLayerAlpha(layer);
1151    const float texX = 1.0f / float(layer->getWidth());
1152    const float texY = 1.0f / float(layer->getHeight());
1153    const float height = rect.getHeight();
1154
1155    setupDraw();
1156
1157    // We must get (and therefore bind) the region mesh buffer
1158    // after we setup drawing in case we need to mess with the
1159    // stencil buffer in setupDraw()
1160    TextureVertex* mesh = mCaches.getRegionMesh();
1161    uint32_t numQuads = 0;
1162
1163    setupDrawWithTexture();
1164    setupDrawColor(alpha, alpha, alpha, alpha);
1165    setupDrawColorFilter(layer->getColorFilter());
1166    setupDrawBlending(layer);
1167    setupDrawProgram();
1168    setupDrawDirtyRegionsDisabled();
1169    setupDrawPureColorUniforms();
1170    setupDrawColorFilterUniforms(layer->getColorFilter());
1171    setupDrawTexture(layer->getTexture());
1172    if (currentTransform()->isPureTranslate()) {
1173        const float x = (int) floorf(rect.left + currentTransform()->getTranslateX() + 0.5f);
1174        const float y = (int) floorf(rect.top + currentTransform()->getTranslateY() + 0.5f);
1175
1176        layer->setFilter(GL_NEAREST);
1177        setupDrawModelView(kModelViewMode_Translate, false,
1178                x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1179    } else {
1180        layer->setFilter(GL_LINEAR);
1181        setupDrawModelView(kModelViewMode_Translate, false,
1182                rect.left, rect.top, rect.right, rect.bottom);
1183    }
1184    setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
1185
1186    for (size_t i = 0; i < count; i++) {
1187        const android::Rect* r = &rects[i];
1188
1189        const float u1 = r->left * texX;
1190        const float v1 = (height - r->top) * texY;
1191        const float u2 = r->right * texX;
1192        const float v2 = (height - r->bottom) * texY;
1193
1194        // TODO: Reject quads outside of the clip
1195        TextureVertex::set(mesh++, r->left, r->top, u1, v1);
1196        TextureVertex::set(mesh++, r->right, r->top, u2, v1);
1197        TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
1198        TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
1199
1200        numQuads++;
1201
1202        if (numQuads >= gMaxNumberOfQuads) {
1203            DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1204                            GL_UNSIGNED_SHORT, NULL));
1205            numQuads = 0;
1206            mesh = mCaches.getRegionMesh();
1207        }
1208    }
1209
1210    if (numQuads > 0) {
1211        DRAW_DOUBLE_STENCIL(glDrawElements(GL_TRIANGLES, numQuads * 6,
1212                        GL_UNSIGNED_SHORT, NULL));
1213    }
1214
1215#if DEBUG_LAYERS_AS_REGIONS
1216    drawRegionRectsDebug(layer->region);
1217#endif
1218
1219    layer->region.clear();
1220}
1221
1222#if DEBUG_LAYERS_AS_REGIONS
1223void OpenGLRenderer::drawRegionRectsDebug(const Region& region) {
1224    size_t count;
1225    const android::Rect* rects = region.getArray(&count);
1226
1227    uint32_t colors[] = {
1228            0x7fff0000, 0x7f00ff00,
1229            0x7f0000ff, 0x7fff00ff,
1230    };
1231
1232    int offset = 0;
1233    int32_t top = rects[0].top;
1234
1235    for (size_t i = 0; i < count; i++) {
1236        if (top != rects[i].top) {
1237            offset ^= 0x2;
1238            top = rects[i].top;
1239        }
1240
1241        SkPaint paint;
1242        paint.setColor(colors[offset + (i & 0x1)]);
1243        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
1244        drawColorRect(r.left, r.top, r.right, r.bottom, paint);
1245    }
1246}
1247#endif
1248
1249void OpenGLRenderer::drawRegionRects(const SkRegion& region, const SkPaint& paint, bool dirty) {
1250    Vector<float> rects;
1251
1252    SkRegion::Iterator it(region);
1253    while (!it.done()) {
1254        const SkIRect& r = it.rect();
1255        rects.push(r.fLeft);
1256        rects.push(r.fTop);
1257        rects.push(r.fRight);
1258        rects.push(r.fBottom);
1259        it.next();
1260    }
1261
1262    drawColorRects(rects.array(), rects.size(), &paint, true, dirty, false);
1263}
1264
1265void OpenGLRenderer::dirtyLayer(const float left, const float top,
1266        const float right, const float bottom, const mat4 transform) {
1267    if (hasLayer()) {
1268        Rect bounds(left, top, right, bottom);
1269        transform.mapRect(bounds);
1270        dirtyLayerUnchecked(bounds, getRegion());
1271    }
1272}
1273
1274void OpenGLRenderer::dirtyLayer(const float left, const float top,
1275        const float right, const float bottom) {
1276    if (hasLayer()) {
1277        Rect bounds(left, top, right, bottom);
1278        dirtyLayerUnchecked(bounds, getRegion());
1279    }
1280}
1281
1282void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
1283    if (bounds.intersect(*currentClipRect())) {
1284        bounds.snapToPixelBoundaries();
1285        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1286        if (!dirty.isEmpty()) {
1287            region->orSelf(dirty);
1288        }
1289    }
1290}
1291
1292void OpenGLRenderer::issueIndexedQuadDraw(Vertex* mesh, GLsizei quadsCount) {
1293    GLsizei elementsCount = quadsCount * 6;
1294    while (elementsCount > 0) {
1295        GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
1296
1297        setupDrawIndexedVertices(&mesh[0].x);
1298        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL);
1299
1300        elementsCount -= drawCount;
1301        // Though there are 4 vertices in a quad, we use 6 indices per
1302        // quad to draw with GL_TRIANGLES
1303        mesh += (drawCount / 6) * 4;
1304    }
1305}
1306
1307void OpenGLRenderer::clearLayerRegions() {
1308    const size_t count = mLayers.size();
1309    if (count == 0) return;
1310
1311    if (!currentSnapshot()->isIgnored()) {
1312        EVENT_LOGD("clearLayerRegions");
1313        // Doing several glScissor/glClear here can negatively impact
1314        // GPUs with a tiler architecture, instead we draw quads with
1315        // the Clear blending mode
1316
1317        // The list contains bounds that have already been clipped
1318        // against their initial clip rect, and the current clip
1319        // is likely different so we need to disable clipping here
1320        bool scissorChanged = mCaches.disableScissor();
1321
1322        Vertex mesh[count * 4];
1323        Vertex* vertex = mesh;
1324
1325        for (uint32_t i = 0; i < count; i++) {
1326            Rect* bounds = mLayers.itemAt(i);
1327
1328            Vertex::set(vertex++, bounds->left, bounds->top);
1329            Vertex::set(vertex++, bounds->right, bounds->top);
1330            Vertex::set(vertex++, bounds->left, bounds->bottom);
1331            Vertex::set(vertex++, bounds->right, bounds->bottom);
1332
1333            delete bounds;
1334        }
1335        // We must clear the list of dirty rects before we
1336        // call setupDraw() to prevent stencil setup to do
1337        // the same thing again
1338        mLayers.clear();
1339
1340        SkPaint clearPaint;
1341        clearPaint.setXfermodeMode(SkXfermode::kClear_Mode);
1342
1343        setupDraw(false);
1344        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
1345        setupDrawBlending(&clearPaint, true);
1346        setupDrawProgram();
1347        setupDrawPureColorUniforms();
1348        setupDrawModelView(kModelViewMode_Translate, false,
1349                0.0f, 0.0f, 0.0f, 0.0f, true);
1350
1351        issueIndexedQuadDraw(&mesh[0], count);
1352
1353        if (scissorChanged) mCaches.enableScissor();
1354    } else {
1355        for (uint32_t i = 0; i < count; i++) {
1356            delete mLayers.itemAt(i);
1357        }
1358        mLayers.clear();
1359    }
1360}
1361
1362///////////////////////////////////////////////////////////////////////////////
1363// State Deferral
1364///////////////////////////////////////////////////////////////////////////////
1365
1366bool OpenGLRenderer::storeDisplayState(DeferredDisplayState& state, int stateDeferFlags) {
1367    const Rect* currentClip = currentClipRect();
1368    const mat4* currentMatrix = currentTransform();
1369
1370    if (stateDeferFlags & kStateDeferFlag_Draw) {
1371        // state has bounds initialized in local coordinates
1372        if (!state.mBounds.isEmpty()) {
1373            currentMatrix->mapRect(state.mBounds);
1374            Rect clippedBounds(state.mBounds);
1375            // NOTE: if we ever want to use this clipping info to drive whether the scissor
1376            // is used, it should more closely duplicate the quickReject logic (in how it uses
1377            // snapToPixelBoundaries)
1378
1379            if(!clippedBounds.intersect(*currentClip)) {
1380                // quick rejected
1381                return true;
1382            }
1383
1384            state.mClipSideFlags = kClipSide_None;
1385            if (!currentClip->contains(state.mBounds)) {
1386                int& flags = state.mClipSideFlags;
1387                // op partially clipped, so record which sides are clipped for clip-aware merging
1388                if (currentClip->left > state.mBounds.left) flags |= kClipSide_Left;
1389                if (currentClip->top > state.mBounds.top) flags |= kClipSide_Top;
1390                if (currentClip->right < state.mBounds.right) flags |= kClipSide_Right;
1391                if (currentClip->bottom < state.mBounds.bottom) flags |= kClipSide_Bottom;
1392            }
1393            state.mBounds.set(clippedBounds);
1394        } else {
1395            // Empty bounds implies size unknown. Label op as conservatively clipped to disable
1396            // overdraw avoidance (since we don't know what it overlaps)
1397            state.mClipSideFlags = kClipSide_ConservativeFull;
1398            state.mBounds.set(*currentClip);
1399        }
1400    }
1401
1402    state.mClipValid = (stateDeferFlags & kStateDeferFlag_Clip);
1403    if (state.mClipValid) {
1404        state.mClip.set(*currentClip);
1405    }
1406
1407    // Transform, drawModifiers, and alpha always deferred, since they are used by state operations
1408    // (Note: saveLayer/restore use colorFilter and alpha, so we just save restore everything)
1409    state.mMatrix.load(*currentMatrix);
1410    state.mDrawModifiers = mDrawModifiers;
1411    state.mAlpha = currentSnapshot()->alpha;
1412
1413    // always store/restore, since it's just a pointer
1414    state.mRoundRectClipState = currentSnapshot()->roundRectClipState;
1415    return false;
1416}
1417
1418void OpenGLRenderer::restoreDisplayState(const DeferredDisplayState& state, bool skipClipRestore) {
1419    setMatrix(state.mMatrix);
1420    mSnapshot->alpha = state.mAlpha;
1421    mDrawModifiers = state.mDrawModifiers;
1422    mSnapshot->roundRectClipState = state.mRoundRectClipState;
1423
1424    if (state.mClipValid && !skipClipRestore) {
1425        mSnapshot->setClip(state.mClip.left, state.mClip.top,
1426                state.mClip.right, state.mClip.bottom);
1427        dirtyClip();
1428    }
1429}
1430
1431/**
1432 * Merged multidraw (such as in drawText and drawBitmaps rely on the fact that no clipping is done
1433 * in the draw path. Instead, clipping is done ahead of time - either as a single clip rect (when at
1434 * least one op is clipped), or disabled entirely (because no merged op is clipped)
1435 *
1436 * This method should be called when restoreDisplayState() won't be restoring the clip
1437 */
1438void OpenGLRenderer::setupMergedMultiDraw(const Rect* clipRect) {
1439    if (clipRect != NULL) {
1440        mSnapshot->setClip(clipRect->left, clipRect->top, clipRect->right, clipRect->bottom);
1441    } else {
1442        mSnapshot->setClip(0, 0, getWidth(), getHeight());
1443    }
1444    dirtyClip();
1445    mCaches.setScissorEnabled(clipRect != NULL || mScissorOptimizationDisabled);
1446}
1447
1448///////////////////////////////////////////////////////////////////////////////
1449// Clipping
1450///////////////////////////////////////////////////////////////////////////////
1451
1452void OpenGLRenderer::setScissorFromClip() {
1453    Rect clip(*currentClipRect());
1454    clip.snapToPixelBoundaries();
1455
1456    if (mCaches.setScissor(clip.left, getViewportHeight() - clip.bottom,
1457            clip.getWidth(), clip.getHeight())) {
1458        mDirtyClip = false;
1459    }
1460}
1461
1462void OpenGLRenderer::ensureStencilBuffer() {
1463    // Thanks to the mismatch between EGL and OpenGL ES FBO we
1464    // cannot attach a stencil buffer to fbo0 dynamically. Let's
1465    // just hope we have one when hasLayer() returns false.
1466    if (hasLayer()) {
1467        attachStencilBufferToLayer(currentSnapshot()->layer);
1468    }
1469}
1470
1471void OpenGLRenderer::attachStencilBufferToLayer(Layer* layer) {
1472    // The layer's FBO is already bound when we reach this stage
1473    if (!layer->getStencilRenderBuffer()) {
1474        // GL_QCOM_tiled_rendering doesn't like it if a renderbuffer
1475        // is attached after we initiated tiling. We must turn it off,
1476        // attach the new render buffer then turn tiling back on
1477        endTiling();
1478
1479        RenderBuffer* buffer = mCaches.renderBufferCache.get(
1480                Stencil::getSmallestStencilFormat(), layer->getWidth(), layer->getHeight());
1481        layer->setStencilRenderBuffer(buffer);
1482
1483        startTiling(layer->clipRect, layer->layer.getHeight());
1484    }
1485}
1486
1487void OpenGLRenderer::setStencilFromClip() {
1488    if (!mCaches.debugOverdraw) {
1489        if (!currentSnapshot()->clipRegion->isEmpty()) {
1490            EVENT_LOGD("setStencilFromClip - enabling");
1491
1492            // NOTE: The order here is important, we must set dirtyClip to false
1493            //       before any draw call to avoid calling back into this method
1494            mDirtyClip = false;
1495
1496            ensureStencilBuffer();
1497
1498            mCaches.stencil.enableWrite();
1499
1500            // Clear and update the stencil, but first make sure we restrict drawing
1501            // to the region's bounds
1502            bool resetScissor = mCaches.enableScissor();
1503            if (resetScissor) {
1504                // The scissor was not set so we now need to update it
1505                setScissorFromClip();
1506            }
1507            mCaches.stencil.clear();
1508
1509            // stash and disable the outline clip state, since stencil doesn't account for outline
1510            bool storedSkipOutlineClip = mSkipOutlineClip;
1511            mSkipOutlineClip = true;
1512
1513            SkPaint paint;
1514            paint.setColor(SK_ColorBLACK);
1515            paint.setXfermodeMode(SkXfermode::kSrc_Mode);
1516
1517            // NOTE: We could use the region contour path to generate a smaller mesh
1518            //       Since we are using the stencil we could use the red book path
1519            //       drawing technique. It might increase bandwidth usage though.
1520
1521            // The last parameter is important: we are not drawing in the color buffer
1522            // so we don't want to dirty the current layer, if any
1523            drawRegionRects(*(currentSnapshot()->clipRegion), paint, false);
1524            if (resetScissor) mCaches.disableScissor();
1525            mSkipOutlineClip = storedSkipOutlineClip;
1526
1527            mCaches.stencil.enableTest();
1528
1529            // Draw the region used to generate the stencil if the appropriate debug
1530            // mode is enabled
1531            if (mCaches.debugStencilClip == Caches::kStencilShowRegion) {
1532                paint.setColor(0x7f0000ff);
1533                paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
1534                drawRegionRects(*(currentSnapshot()->clipRegion), paint);
1535            }
1536        } else {
1537            EVENT_LOGD("setStencilFromClip - disabling");
1538            mCaches.stencil.disable();
1539        }
1540    }
1541}
1542
1543/**
1544 * Returns false and sets scissor enable based upon bounds if drawing won't be clipped out.
1545 *
1546 * @param paint if not null, the bounds will be expanded to account for stroke depending on paint
1547 *         style, and tessellated AA ramp
1548 */
1549bool OpenGLRenderer::quickRejectSetupScissor(float left, float top, float right, float bottom,
1550        const SkPaint* paint) {
1551    bool snapOut = paint && paint->isAntiAlias();
1552
1553    if (paint && paint->getStyle() != SkPaint::kFill_Style) {
1554        float outset = paint->getStrokeWidth() * 0.5f;
1555        left -= outset;
1556        top -= outset;
1557        right += outset;
1558        bottom += outset;
1559    }
1560
1561    bool clipRequired = false;
1562    bool roundRectClipRequired = false;
1563    if (calculateQuickRejectForScissor(left, top, right, bottom,
1564            &clipRequired, &roundRectClipRequired, snapOut)) {
1565        return true;
1566    }
1567
1568    // not quick rejected, so enable the scissor if clipRequired
1569    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
1570    mSkipOutlineClip = !roundRectClipRequired;
1571    return false;
1572}
1573
1574void OpenGLRenderer::debugClip() {
1575#if DEBUG_CLIP_REGIONS
1576    if (!currentSnapshot()->clipRegion->isEmpty()) {
1577        SkPaint paint;
1578        paint.setColor(0x7f00ff00);
1579        drawRegionRects(*(currentSnapshot()->clipRegion, paint);
1580
1581    }
1582#endif
1583}
1584
1585///////////////////////////////////////////////////////////////////////////////
1586// Drawing commands
1587///////////////////////////////////////////////////////////////////////////////
1588
1589void OpenGLRenderer::setupDraw(bool clearLayer) {
1590    // TODO: It would be best if we could do this before quickRejectSetupScissor()
1591    //       changes the scissor test state
1592    if (clearLayer) clearLayerRegions();
1593    // Make sure setScissor & setStencil happen at the beginning of
1594    // this method
1595    if (mDirtyClip) {
1596        if (mCaches.scissorEnabled) {
1597            setScissorFromClip();
1598        }
1599
1600        if (clearLayer) {
1601            setStencilFromClip();
1602        } else {
1603            // While clearing layer, force disable stencil buffer, since
1604            // it's invalid to stencil-clip *during* the layer clear
1605            mCaches.stencil.disable();
1606        }
1607    }
1608
1609    mDescription.reset();
1610
1611    mSetShaderColor = false;
1612    mColorSet = false;
1613    mColorA = mColorR = mColorG = mColorB = 0.0f;
1614    mTextureUnit = 0;
1615    mTrackDirtyRegions = true;
1616
1617    // Enable debug highlight when what we're about to draw is tested against
1618    // the stencil buffer and if stencil highlight debugging is on
1619    mDescription.hasDebugHighlight = !mCaches.debugOverdraw &&
1620            mCaches.debugStencilClip == Caches::kStencilShowHighlight &&
1621            mCaches.stencil.isTestEnabled();
1622
1623    mDescription.emulateStencil = mCountOverdraw;
1624}
1625
1626void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1627    mDescription.hasTexture = true;
1628    mDescription.hasAlpha8Texture = isAlpha8;
1629}
1630
1631void OpenGLRenderer::setupDrawWithTextureAndColor(bool isAlpha8) {
1632    mDescription.hasTexture = true;
1633    mDescription.hasColors = true;
1634    mDescription.hasAlpha8Texture = isAlpha8;
1635}
1636
1637void OpenGLRenderer::setupDrawWithExternalTexture() {
1638    mDescription.hasExternalTexture = true;
1639}
1640
1641void OpenGLRenderer::setupDrawNoTexture() {
1642    mCaches.disableTexCoordsVertexArray();
1643}
1644
1645void OpenGLRenderer::setupDrawVertexAlpha(bool useShadowAlphaInterp) {
1646    mDescription.hasVertexAlpha = true;
1647    mDescription.useShadowAlphaInterp = useShadowAlphaInterp;
1648}
1649
1650void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1651    mColorA = alpha / 255.0f;
1652    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1653    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1654    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1655    mColorSet = true;
1656    mSetShaderColor = mDescription.setColorModulate(mColorA);
1657}
1658
1659void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1660    mColorA = alpha / 255.0f;
1661    mColorR = mColorA * ((color >> 16) & 0xFF) / 255.0f;
1662    mColorG = mColorA * ((color >>  8) & 0xFF) / 255.0f;
1663    mColorB = mColorA * ((color      ) & 0xFF) / 255.0f;
1664    mColorSet = true;
1665    mSetShaderColor = mDescription.setAlpha8ColorModulate(mColorR, mColorG, mColorB, mColorA);
1666}
1667
1668void OpenGLRenderer::setupDrawTextGamma(const SkPaint* paint) {
1669    mCaches.fontRenderer->describe(mDescription, paint);
1670}
1671
1672void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1673    mColorA = a;
1674    mColorR = r;
1675    mColorG = g;
1676    mColorB = b;
1677    mColorSet = true;
1678    mSetShaderColor = mDescription.setColorModulate(a);
1679}
1680
1681void OpenGLRenderer::setupDrawShader(const SkShader* shader) {
1682    if (shader != NULL) {
1683        SkiaShader::describe(&mCaches, mDescription, mExtensions, *shader);
1684    }
1685}
1686
1687void OpenGLRenderer::setupDrawColorFilter(const SkColorFilter* filter) {
1688    if (filter == NULL) {
1689        return;
1690    }
1691
1692    SkXfermode::Mode mode;
1693    if (filter->asColorMode(NULL, &mode)) {
1694        mDescription.colorOp = ProgramDescription::kColorBlend;
1695        mDescription.colorMode = mode;
1696    } else if (filter->asColorMatrix(NULL)) {
1697        mDescription.colorOp = ProgramDescription::kColorMatrix;
1698    }
1699}
1700
1701void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1702    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1703        mColorA = 1.0f;
1704        mColorR = mColorG = mColorB = 0.0f;
1705        mSetShaderColor = mDescription.modulate = true;
1706    }
1707}
1708
1709static bool isBlendedColorFilter(const SkColorFilter* filter) {
1710    if (filter == NULL) {
1711        return false;
1712    }
1713    return (filter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag) == 0;
1714}
1715
1716void OpenGLRenderer::setupDrawBlending(const Layer* layer, bool swapSrcDst) {
1717    SkXfermode::Mode mode = layer->getMode();
1718    // When the blending mode is kClear_Mode, we need to use a modulate color
1719    // argb=1,0,0,0
1720    accountForClear(mode);
1721    // TODO: check shader blending, once we have shader drawing support for layers.
1722    bool blend = layer->isBlend() || getLayerAlpha(layer) < 1.0f ||
1723            (mColorSet && mColorA < 1.0f) || isBlendedColorFilter(layer->getColorFilter());
1724    chooseBlending(blend, mode, mDescription, swapSrcDst);
1725}
1726
1727void OpenGLRenderer::setupDrawBlending(const SkPaint* paint, bool blend, bool swapSrcDst) {
1728    SkXfermode::Mode mode = getXfermodeDirect(paint);
1729    // When the blending mode is kClear_Mode, we need to use a modulate color
1730    // argb=1,0,0,0
1731    accountForClear(mode);
1732    blend |= (mColorSet && mColorA < 1.0f) ||
1733            (getShader(paint) && !getShader(paint)->isOpaque()) ||
1734            isBlendedColorFilter(getColorFilter(paint));
1735    chooseBlending(blend, mode, mDescription, swapSrcDst);
1736}
1737
1738void OpenGLRenderer::setupDrawProgram() {
1739    useProgram(mCaches.programCache.get(mDescription));
1740    if (mDescription.hasRoundRectClip) {
1741        // TODO: avoid doing this repeatedly, stashing state pointer in program
1742        const RoundRectClipState* state = mSnapshot->roundRectClipState;
1743        const Rect& innerRect = state->innerRect;
1744        glUniform4f(mCaches.currentProgram->getUniform("roundRectInnerRectLTRB"),
1745                innerRect.left, innerRect.top,
1746                innerRect.right, innerRect.bottom);
1747        glUniform1f(mCaches.currentProgram->getUniform("roundRectRadius"),
1748                state->radius);
1749        glUniformMatrix4fv(mCaches.currentProgram->getUniform("roundRectInvTransform"),
1750                1, GL_FALSE, &state->matrix.data[0]);
1751    }
1752}
1753
1754void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1755    mTrackDirtyRegions = false;
1756}
1757
1758void OpenGLRenderer::setupDrawModelView(ModelViewMode mode, bool offset,
1759        float left, float top, float right, float bottom, bool ignoreTransform) {
1760    mModelViewMatrix.loadTranslate(left, top, 0.0f);
1761    if (mode == kModelViewMode_TranslateAndScale) {
1762        mModelViewMatrix.scale(right - left, bottom - top, 1.0f);
1763    }
1764
1765    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1766    const Matrix4& transformMatrix = ignoreTransform ? Matrix4::identity() : *currentTransform();
1767    mCaches.currentProgram->set(mSnapshot->getOrthoMatrix(), mModelViewMatrix, transformMatrix, offset);
1768    if (dirty && mTrackDirtyRegions) {
1769        if (!ignoreTransform) {
1770            dirtyLayer(left, top, right, bottom, *currentTransform());
1771        } else {
1772            dirtyLayer(left, top, right, bottom);
1773        }
1774    }
1775}
1776
1777void OpenGLRenderer::setupDrawColorUniforms(bool hasShader) {
1778    if ((mColorSet && !hasShader) || (hasShader && mSetShaderColor)) {
1779        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1780    }
1781}
1782
1783void OpenGLRenderer::setupDrawPureColorUniforms() {
1784    if (mSetShaderColor) {
1785        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1786    }
1787}
1788
1789void OpenGLRenderer::setupDrawShaderUniforms(const SkShader* shader, bool ignoreTransform) {
1790    if (shader == NULL) {
1791        return;
1792    }
1793
1794    if (ignoreTransform) {
1795        // if ignoreTransform=true was passed to setupDrawModelView, undo currentTransform()
1796        // because it was built into modelView / the geometry, and the description needs to
1797        // compensate.
1798        mat4 modelViewWithoutTransform;
1799        modelViewWithoutTransform.loadInverse(*currentTransform());
1800        modelViewWithoutTransform.multiply(mModelViewMatrix);
1801        mModelViewMatrix.load(modelViewWithoutTransform);
1802    }
1803
1804    SkiaShader::setupProgram(&mCaches, mModelViewMatrix, &mTextureUnit, mExtensions, *shader);
1805}
1806
1807void OpenGLRenderer::setupDrawColorFilterUniforms(const SkColorFilter* filter) {
1808    if (NULL == filter) {
1809        return;
1810    }
1811
1812    SkColor color;
1813    SkXfermode::Mode mode;
1814    if (filter->asColorMode(&color, &mode)) {
1815        const int alpha = SkColorGetA(color);
1816        const GLfloat a = alpha / 255.0f;
1817        const GLfloat r = a * SkColorGetR(color) / 255.0f;
1818        const GLfloat g = a * SkColorGetG(color) / 255.0f;
1819        const GLfloat b = a * SkColorGetB(color) / 255.0f;
1820        glUniform4f(mCaches.currentProgram->getUniform("colorBlend"), r, g, b, a);
1821        return;
1822    }
1823
1824    SkScalar srcColorMatrix[20];
1825    if (filter->asColorMatrix(srcColorMatrix)) {
1826
1827        float colorMatrix[16];
1828        memcpy(colorMatrix, srcColorMatrix, 4 * sizeof(float));
1829        memcpy(&colorMatrix[4], &srcColorMatrix[5], 4 * sizeof(float));
1830        memcpy(&colorMatrix[8], &srcColorMatrix[10], 4 * sizeof(float));
1831        memcpy(&colorMatrix[12], &srcColorMatrix[15], 4 * sizeof(float));
1832
1833        // Skia uses the range [0..255] for the addition vector, but we need
1834        // the [0..1] range to apply the vector in GLSL
1835        float colorVector[4];
1836        colorVector[0] = srcColorMatrix[4] / 255.0f;
1837        colorVector[1] = srcColorMatrix[9] / 255.0f;
1838        colorVector[2] = srcColorMatrix[14] / 255.0f;
1839        colorVector[3] = srcColorMatrix[19] / 255.0f;
1840
1841        glUniformMatrix4fv(mCaches.currentProgram->getUniform("colorMatrix"), 1,
1842                GL_FALSE, colorMatrix);
1843        glUniform4fv(mCaches.currentProgram->getUniform("colorMatrixVector"), 1, colorVector);
1844        return;
1845    }
1846
1847    // it is an error if we ever get here
1848}
1849
1850void OpenGLRenderer::setupDrawTextGammaUniforms() {
1851    mCaches.fontRenderer->setupProgram(mDescription, mCaches.currentProgram);
1852}
1853
1854void OpenGLRenderer::setupDrawSimpleMesh() {
1855    bool force = mCaches.bindMeshBuffer();
1856    mCaches.bindPositionVertexPointer(force, 0);
1857    mCaches.unbindIndicesBuffer();
1858}
1859
1860void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1861    if (texture) bindTexture(texture);
1862    mTextureUnit++;
1863    mCaches.enableTexCoordsVertexArray();
1864}
1865
1866void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1867    bindExternalTexture(texture);
1868    mTextureUnit++;
1869    mCaches.enableTexCoordsVertexArray();
1870}
1871
1872void OpenGLRenderer::setupDrawTextureTransform() {
1873    mDescription.hasTextureTransform = true;
1874}
1875
1876void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1877    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1878            GL_FALSE, &transform.data[0]);
1879}
1880
1881void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1882        const GLvoid* texCoords, GLuint vbo) {
1883    bool force = false;
1884    if (!vertices || vbo) {
1885        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1886    } else {
1887        force = mCaches.unbindMeshBuffer();
1888    }
1889
1890    mCaches.bindPositionVertexPointer(force, vertices);
1891    if (mCaches.currentProgram->texCoords >= 0) {
1892        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1893    }
1894
1895    mCaches.unbindIndicesBuffer();
1896}
1897
1898void OpenGLRenderer::setupDrawMesh(const GLvoid* vertices,
1899        const GLvoid* texCoords, const GLvoid* colors) {
1900    bool force = mCaches.unbindMeshBuffer();
1901    GLsizei stride = sizeof(ColorTextureVertex);
1902
1903    mCaches.bindPositionVertexPointer(force, vertices, stride);
1904    if (mCaches.currentProgram->texCoords >= 0) {
1905        mCaches.bindTexCoordsVertexPointer(force, texCoords, stride);
1906    }
1907    int slot = mCaches.currentProgram->getAttrib("colors");
1908    if (slot >= 0) {
1909        glEnableVertexAttribArray(slot);
1910        glVertexAttribPointer(slot, 4, GL_FLOAT, GL_FALSE, stride, colors);
1911    }
1912
1913    mCaches.unbindIndicesBuffer();
1914}
1915
1916void OpenGLRenderer::setupDrawMeshIndices(const GLvoid* vertices,
1917        const GLvoid* texCoords, GLuint vbo) {
1918    bool force = false;
1919    // If vbo is != 0 we want to treat the vertices parameter as an offset inside
1920    // a VBO. However, if vertices is set to NULL and vbo == 0 then we want to
1921    // use the default VBO found in Caches
1922    if (!vertices || vbo) {
1923        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1924    } else {
1925        force = mCaches.unbindMeshBuffer();
1926    }
1927    mCaches.bindQuadIndicesBuffer();
1928
1929    mCaches.bindPositionVertexPointer(force, vertices);
1930    if (mCaches.currentProgram->texCoords >= 0) {
1931        mCaches.bindTexCoordsVertexPointer(force, texCoords);
1932    }
1933}
1934
1935void OpenGLRenderer::setupDrawIndexedVertices(GLvoid* vertices) {
1936    bool force = mCaches.unbindMeshBuffer();
1937    mCaches.bindQuadIndicesBuffer();
1938    mCaches.bindPositionVertexPointer(force, vertices, gVertexStride);
1939}
1940
1941///////////////////////////////////////////////////////////////////////////////
1942// Drawing
1943///////////////////////////////////////////////////////////////////////////////
1944
1945status_t OpenGLRenderer::drawRenderNode(RenderNode* renderNode, Rect& dirty, int32_t replayFlags) {
1946    status_t status;
1947    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1948    // will be performed by the display list itself
1949    if (renderNode && renderNode->isRenderable()) {
1950        // compute 3d ordering
1951        renderNode->computeOrdering();
1952        if (CC_UNLIKELY(mCaches.drawDeferDisabled)) {
1953            status = startFrame();
1954            ReplayStateStruct replayStruct(*this, dirty, replayFlags);
1955            renderNode->replay(replayStruct, 0);
1956            return status | replayStruct.mDrawGlStatus;
1957        }
1958
1959        bool avoidOverdraw = !mCaches.debugOverdraw && !mCountOverdraw; // shh, don't tell devs!
1960        DeferredDisplayList deferredList(*currentClipRect(), avoidOverdraw);
1961        DeferStateStruct deferStruct(deferredList, *this, replayFlags);
1962        renderNode->defer(deferStruct, 0);
1963
1964        flushLayers();
1965        status = startFrame();
1966
1967        return deferredList.flush(*this, dirty) | status;
1968    }
1969
1970    // Even if there is no drawing command(Ex: invisible),
1971    // it still needs startFrame to clear buffer and start tiling.
1972    return startFrame();
1973}
1974
1975void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, const SkPaint* paint) {
1976    int color = paint != NULL ? paint->getColor() : 0;
1977
1978    float x = left;
1979    float y = top;
1980
1981    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1982
1983    bool ignoreTransform = false;
1984    if (currentTransform()->isPureTranslate()) {
1985        x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
1986        y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
1987        ignoreTransform = true;
1988
1989        texture->setFilter(GL_NEAREST, true);
1990    } else {
1991        texture->setFilter(getFilter(paint), true);
1992    }
1993
1994    // No need to check for a UV mapper on the texture object, only ARGB_8888
1995    // bitmaps get packed in the atlas
1996    drawAlpha8TextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1997            paint, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1998            GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
1999}
2000
2001/**
2002 * Important note: this method is intended to draw batches of bitmaps and
2003 * will not set the scissor enable or dirty the current layer, if any.
2004 * The caller is responsible for properly dirtying the current layer.
2005 */
2006status_t OpenGLRenderer::drawBitmaps(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
2007        int bitmapCount, TextureVertex* vertices, bool pureTranslate,
2008        const Rect& bounds, const SkPaint* paint) {
2009    mCaches.activeTexture(0);
2010    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2011    if (!texture) return DrawGlInfo::kStatusDone;
2012
2013    const AutoTexture autoCleanup(texture);
2014
2015    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2016    texture->setFilter(pureTranslate ? GL_NEAREST : getFilter(paint), true);
2017
2018    const float x = (int) floorf(bounds.left + 0.5f);
2019    const float y = (int) floorf(bounds.top + 0.5f);
2020    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2021        drawAlpha8TextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
2022                texture->id, paint, &vertices[0].x, &vertices[0].u,
2023                GL_TRIANGLES, bitmapCount * 6, true,
2024                kModelViewMode_Translate, false);
2025    } else {
2026        drawTextureMesh(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
2027                texture->id, paint, texture->blend, &vertices[0].x, &vertices[0].u,
2028                GL_TRIANGLES, bitmapCount * 6, false, true, 0,
2029                kModelViewMode_Translate, false);
2030    }
2031
2032    return DrawGlInfo::kStatusDrew;
2033}
2034
2035status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap, const SkPaint* paint) {
2036    if (quickRejectSetupScissor(0, 0, bitmap->width(), bitmap->height())) {
2037        return DrawGlInfo::kStatusDone;
2038    }
2039
2040    mCaches.activeTexture(0);
2041    Texture* texture = getTexture(bitmap);
2042    if (!texture) return DrawGlInfo::kStatusDone;
2043    const AutoTexture autoCleanup(texture);
2044
2045    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2046        drawAlphaBitmap(texture, 0, 0, paint);
2047    } else {
2048        drawTextureRect(0, 0, bitmap->width(), bitmap->height(), texture, paint);
2049    }
2050
2051    return DrawGlInfo::kStatusDrew;
2052}
2053
2054status_t OpenGLRenderer::drawBitmapData(const SkBitmap* bitmap, const SkPaint* paint) {
2055    if (quickRejectSetupScissor(0, 0, bitmap->width(), bitmap->height())) {
2056        return DrawGlInfo::kStatusDone;
2057    }
2058
2059    mCaches.activeTexture(0);
2060    Texture* texture = mCaches.textureCache.getTransient(bitmap);
2061    const AutoTexture autoCleanup(texture);
2062
2063    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2064        drawAlphaBitmap(texture, 0, 0, paint);
2065    } else {
2066        drawTextureRect(0, 0, bitmap->width(), bitmap->height(), texture, paint);
2067    }
2068
2069    return DrawGlInfo::kStatusDrew;
2070}
2071
2072status_t OpenGLRenderer::drawBitmapMesh(const SkBitmap* bitmap, int meshWidth, int meshHeight,
2073        const float* vertices, const int* colors, const SkPaint* paint) {
2074    if (!vertices || currentSnapshot()->isIgnored()) {
2075        return DrawGlInfo::kStatusDone;
2076    }
2077
2078    // TODO: use quickReject on bounds from vertices
2079    mCaches.enableScissor();
2080
2081    float left = FLT_MAX;
2082    float top = FLT_MAX;
2083    float right = FLT_MIN;
2084    float bottom = FLT_MIN;
2085
2086    const uint32_t count = meshWidth * meshHeight * 6;
2087
2088    Vector<ColorTextureVertex> mesh; // TODO: use C++11 unique_ptr
2089    mesh.setCapacity(count);
2090    ColorTextureVertex* vertex = mesh.editArray();
2091
2092    bool cleanupColors = false;
2093    if (!colors) {
2094        uint32_t colorsCount = (meshWidth + 1) * (meshHeight + 1);
2095        int* newColors = new int[colorsCount];
2096        memset(newColors, 0xff, colorsCount * sizeof(int));
2097        colors = newColors;
2098        cleanupColors = true;
2099    }
2100
2101    mCaches.activeTexture(0);
2102    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
2103    const UvMapper& mapper(getMapper(texture));
2104
2105    for (int32_t y = 0; y < meshHeight; y++) {
2106        for (int32_t x = 0; x < meshWidth; x++) {
2107            uint32_t i = (y * (meshWidth + 1) + x) * 2;
2108
2109            float u1 = float(x) / meshWidth;
2110            float u2 = float(x + 1) / meshWidth;
2111            float v1 = float(y) / meshHeight;
2112            float v2 = float(y + 1) / meshHeight;
2113
2114            mapper.map(u1, v1, u2, v2);
2115
2116            int ax = i + (meshWidth + 1) * 2;
2117            int ay = ax + 1;
2118            int bx = i;
2119            int by = bx + 1;
2120            int cx = i + 2;
2121            int cy = cx + 1;
2122            int dx = i + (meshWidth + 1) * 2 + 2;
2123            int dy = dx + 1;
2124
2125            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2126            ColorTextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2, colors[ax / 2]);
2127            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2128
2129            ColorTextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2, colors[dx / 2]);
2130            ColorTextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1, colors[bx / 2]);
2131            ColorTextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1, colors[cx / 2]);
2132
2133            left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
2134            top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
2135            right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
2136            bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
2137        }
2138    }
2139
2140    if (quickRejectSetupScissor(left, top, right, bottom)) {
2141        if (cleanupColors) delete[] colors;
2142        return DrawGlInfo::kStatusDone;
2143    }
2144
2145    if (!texture) {
2146        texture = mCaches.textureCache.get(bitmap);
2147        if (!texture) {
2148            if (cleanupColors) delete[] colors;
2149            return DrawGlInfo::kStatusDone;
2150        }
2151    }
2152    const AutoTexture autoCleanup(texture);
2153
2154    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2155    texture->setFilter(getFilter(paint), true);
2156
2157    int alpha;
2158    SkXfermode::Mode mode;
2159    getAlphaAndMode(paint, &alpha, &mode);
2160
2161    float a = alpha / 255.0f;
2162
2163    if (hasLayer()) {
2164        dirtyLayer(left, top, right, bottom, *currentTransform());
2165    }
2166
2167    setupDraw();
2168    setupDrawWithTextureAndColor();
2169    setupDrawColor(a, a, a, a);
2170    setupDrawColorFilter(getColorFilter(paint));
2171    setupDrawBlending(paint, true);
2172    setupDrawProgram();
2173    setupDrawDirtyRegionsDisabled();
2174    setupDrawModelView(kModelViewMode_TranslateAndScale, false, 0.0f, 0.0f, 1.0f, 1.0f);
2175    setupDrawTexture(texture->id);
2176    setupDrawPureColorUniforms();
2177    setupDrawColorFilterUniforms(getColorFilter(paint));
2178    setupDrawMesh(&mesh[0].x, &mesh[0].u, &mesh[0].r);
2179
2180    glDrawArrays(GL_TRIANGLES, 0, count);
2181
2182    int slot = mCaches.currentProgram->getAttrib("colors");
2183    if (slot >= 0) {
2184        glDisableVertexAttribArray(slot);
2185    }
2186
2187    if (cleanupColors) delete[] colors;
2188
2189    return DrawGlInfo::kStatusDrew;
2190}
2191
2192status_t OpenGLRenderer::drawBitmap(const SkBitmap* bitmap,
2193         float srcLeft, float srcTop, float srcRight, float srcBottom,
2194         float dstLeft, float dstTop, float dstRight, float dstBottom,
2195         const SkPaint* paint) {
2196    if (quickRejectSetupScissor(dstLeft, dstTop, dstRight, dstBottom)) {
2197        return DrawGlInfo::kStatusDone;
2198    }
2199
2200    mCaches.activeTexture(0);
2201    Texture* texture = getTexture(bitmap);
2202    if (!texture) return DrawGlInfo::kStatusDone;
2203    const AutoTexture autoCleanup(texture);
2204
2205    const float width = texture->width;
2206    const float height = texture->height;
2207
2208    float u1 = fmax(0.0f, srcLeft / width);
2209    float v1 = fmax(0.0f, srcTop / height);
2210    float u2 = fmin(1.0f, srcRight / width);
2211    float v2 = fmin(1.0f, srcBottom / height);
2212
2213    getMapper(texture).map(u1, v1, u2, v2);
2214
2215    mCaches.unbindMeshBuffer();
2216    resetDrawTextureTexCoords(u1, v1, u2, v2);
2217
2218    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2219
2220    float scaleX = (dstRight - dstLeft) / (srcRight - srcLeft);
2221    float scaleY = (dstBottom - dstTop) / (srcBottom - srcTop);
2222
2223    bool scaled = scaleX != 1.0f || scaleY != 1.0f;
2224    // Apply a scale transform on the canvas only when a shader is in use
2225    // Skia handles the ratio between the dst and src rects as a scale factor
2226    // when a shader is set
2227    bool useScaleTransform = getShader(paint) && scaled;
2228    bool ignoreTransform = false;
2229
2230    if (CC_LIKELY(currentTransform()->isPureTranslate() && !useScaleTransform)) {
2231        float x = (int) floorf(dstLeft + currentTransform()->getTranslateX() + 0.5f);
2232        float y = (int) floorf(dstTop + currentTransform()->getTranslateY() + 0.5f);
2233
2234        dstRight = x + (dstRight - dstLeft);
2235        dstBottom = y + (dstBottom - dstTop);
2236
2237        dstLeft = x;
2238        dstTop = y;
2239
2240        texture->setFilter(scaled ? getFilter(paint) : GL_NEAREST, true);
2241        ignoreTransform = true;
2242    } else {
2243        texture->setFilter(getFilter(paint), true);
2244    }
2245
2246    if (CC_UNLIKELY(useScaleTransform)) {
2247        save(SkCanvas::kMatrix_SaveFlag);
2248        translate(dstLeft, dstTop);
2249        scale(scaleX, scaleY);
2250
2251        dstLeft = 0.0f;
2252        dstTop = 0.0f;
2253
2254        dstRight = srcRight - srcLeft;
2255        dstBottom = srcBottom - srcTop;
2256    }
2257
2258    if (CC_UNLIKELY(bitmap->colorType() == kAlpha_8_SkColorType)) {
2259        drawAlpha8TextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2260                texture->id, paint,
2261                &mMeshVertices[0].x, &mMeshVertices[0].u,
2262                GL_TRIANGLE_STRIP, gMeshCount, ignoreTransform);
2263    } else {
2264        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom,
2265                texture->id, paint, texture->blend,
2266                &mMeshVertices[0].x, &mMeshVertices[0].u,
2267                GL_TRIANGLE_STRIP, gMeshCount, false, ignoreTransform);
2268    }
2269
2270    if (CC_UNLIKELY(useScaleTransform)) {
2271        restore();
2272    }
2273
2274    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
2275
2276    return DrawGlInfo::kStatusDrew;
2277}
2278
2279status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Res_png_9patch* patch,
2280        float left, float top, float right, float bottom, const SkPaint* paint) {
2281    if (quickRejectSetupScissor(left, top, right, bottom)) {
2282        return DrawGlInfo::kStatusDone;
2283    }
2284
2285    AssetAtlas::Entry* entry = mCaches.assetAtlas.getEntry(bitmap);
2286    const Patch* mesh = mCaches.patchCache.get(entry, bitmap->width(), bitmap->height(),
2287            right - left, bottom - top, patch);
2288
2289    return drawPatch(bitmap, mesh, entry, left, top, right, bottom, paint);
2290}
2291
2292status_t OpenGLRenderer::drawPatch(const SkBitmap* bitmap, const Patch* mesh,
2293        AssetAtlas::Entry* entry, float left, float top, float right, float bottom,
2294        const SkPaint* paint) {
2295    if (quickRejectSetupScissor(left, top, right, bottom)) {
2296        return DrawGlInfo::kStatusDone;
2297    }
2298
2299    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
2300        mCaches.activeTexture(0);
2301        Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2302        if (!texture) return DrawGlInfo::kStatusDone;
2303        const AutoTexture autoCleanup(texture);
2304
2305        texture->setWrap(GL_CLAMP_TO_EDGE, true);
2306        texture->setFilter(GL_LINEAR, true);
2307
2308        const bool pureTranslate = currentTransform()->isPureTranslate();
2309        // Mark the current layer dirty where we are going to draw the patch
2310        if (hasLayer() && mesh->hasEmptyQuads) {
2311            const float offsetX = left + currentTransform()->getTranslateX();
2312            const float offsetY = top + currentTransform()->getTranslateY();
2313            const size_t count = mesh->quads.size();
2314            for (size_t i = 0; i < count; i++) {
2315                const Rect& bounds = mesh->quads.itemAt(i);
2316                if (CC_LIKELY(pureTranslate)) {
2317                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
2318                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
2319                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
2320                } else {
2321                    dirtyLayer(left + bounds.left, top + bounds.top,
2322                            left + bounds.right, top + bounds.bottom, *currentTransform());
2323                }
2324            }
2325        }
2326
2327        bool ignoreTransform = false;
2328        if (CC_LIKELY(pureTranslate)) {
2329            const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
2330            const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
2331
2332            right = x + right - left;
2333            bottom = y + bottom - top;
2334            left = x;
2335            top = y;
2336            ignoreTransform = true;
2337        }
2338        drawIndexedTextureMesh(left, top, right, bottom, texture->id, paint,
2339                texture->blend, (GLvoid*) mesh->offset, (GLvoid*) mesh->textureOffset,
2340                GL_TRIANGLES, mesh->indexCount, false, ignoreTransform,
2341                mCaches.patchCache.getMeshBuffer(), kModelViewMode_Translate, !mesh->hasEmptyQuads);
2342    }
2343
2344    return DrawGlInfo::kStatusDrew;
2345}
2346
2347/**
2348 * Important note: this method is intended to draw batches of 9-patch objects and
2349 * will not set the scissor enable or dirty the current layer, if any.
2350 * The caller is responsible for properly dirtying the current layer.
2351 */
2352status_t OpenGLRenderer::drawPatches(const SkBitmap* bitmap, AssetAtlas::Entry* entry,
2353        TextureVertex* vertices, uint32_t indexCount, const SkPaint* paint) {
2354    mCaches.activeTexture(0);
2355    Texture* texture = entry ? entry->texture : mCaches.textureCache.get(bitmap);
2356    if (!texture) return DrawGlInfo::kStatusDone;
2357    const AutoTexture autoCleanup(texture);
2358
2359    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2360    texture->setFilter(GL_LINEAR, true);
2361
2362    drawIndexedTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, paint,
2363            texture->blend, &vertices[0].x, &vertices[0].u,
2364            GL_TRIANGLES, indexCount, false, true, 0, kModelViewMode_Translate, false);
2365
2366    return DrawGlInfo::kStatusDrew;
2367}
2368
2369status_t OpenGLRenderer::drawVertexBuffer(float translateX, float translateY,
2370        const VertexBuffer& vertexBuffer, const SkPaint* paint, int displayFlags) {
2371    // not missing call to quickReject/dirtyLayer, always done at a higher level
2372    if (!vertexBuffer.getVertexCount()) {
2373        // no vertices to draw
2374        return DrawGlInfo::kStatusDone;
2375    }
2376
2377    Rect bounds(vertexBuffer.getBounds());
2378    bounds.translate(translateX, translateY);
2379    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom, *currentTransform());
2380
2381    int color = paint->getColor();
2382    bool isAA = paint->isAntiAlias();
2383
2384    setupDraw();
2385    setupDrawNoTexture();
2386    if (isAA) setupDrawVertexAlpha((displayFlags & kVertexBuffer_ShadowInterp));
2387    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
2388    setupDrawColorFilter(getColorFilter(paint));
2389    setupDrawShader(getShader(paint));
2390    setupDrawBlending(paint, isAA);
2391    setupDrawProgram();
2392    setupDrawModelView(kModelViewMode_Translate, (displayFlags & kVertexBuffer_Offset),
2393            translateX, translateY, 0, 0);
2394    setupDrawColorUniforms(getShader(paint));
2395    setupDrawColorFilterUniforms(getColorFilter(paint));
2396    setupDrawShaderUniforms(getShader(paint));
2397
2398    const void* vertices = vertexBuffer.getBuffer();
2399    bool force = mCaches.unbindMeshBuffer();
2400    mCaches.bindPositionVertexPointer(true, vertices, isAA ? gAlphaVertexStride : gVertexStride);
2401    mCaches.resetTexCoordsVertexPointer();
2402
2403    int alphaSlot = -1;
2404    if (isAA) {
2405        void* alphaCoords = ((GLbyte*) vertices) + gVertexAlphaOffset;
2406        alphaSlot = mCaches.currentProgram->getAttrib("vtxAlpha");
2407        // TODO: avoid enable/disable in back to back uses of the alpha attribute
2408        glEnableVertexAttribArray(alphaSlot);
2409        glVertexAttribPointer(alphaSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, alphaCoords);
2410    }
2411
2412    const VertexBuffer::Mode mode = vertexBuffer.getMode();
2413    if (mode == VertexBuffer::kStandard) {
2414        mCaches.unbindIndicesBuffer();
2415        glDrawArrays(GL_TRIANGLE_STRIP, 0, vertexBuffer.getVertexCount());
2416    } else if (mode == VertexBuffer::kOnePolyRingShadow) {
2417        mCaches.bindShadowIndicesBuffer();
2418        glDrawElements(GL_TRIANGLE_STRIP, ONE_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2419    } else if (mode == VertexBuffer::kTwoPolyRingShadow) {
2420        mCaches.bindShadowIndicesBuffer();
2421        glDrawElements(GL_TRIANGLE_STRIP, TWO_POLY_RING_SHADOW_INDEX_COUNT, GL_UNSIGNED_SHORT, 0);
2422    } else if (mode == VertexBuffer::kIndices) {
2423        mCaches.unbindIndicesBuffer();
2424        glDrawElements(GL_TRIANGLE_STRIP, vertexBuffer.getIndexCount(), GL_UNSIGNED_SHORT,
2425                vertexBuffer.getIndices());
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    int displayFlags = paint->isAntiAlias() ? 0 : kVertexBuffer_Offset;
2476    return drawVertexBuffer(buffer, paint, displayFlags);
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    int displayFlags = paint->isAntiAlias() ? 0 : kVertexBuffer_Offset;
2493    return drawVertexBuffer(buffer, paint, displayFlags);
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()
2528            || quickRejectSetupScissor(left, top, right, bottom, p)
2529            || paintWillNotDraw(*p)) {
2530        return DrawGlInfo::kStatusDone;
2531    }
2532
2533    if (p->getPathEffect() != 0) {
2534        mCaches.activeTexture(0);
2535        const PathTexture* texture = mCaches.pathCache.getRoundRect(
2536                right - left, bottom - top, rx, ry, p);
2537        return drawShape(left, top, texture, p);
2538    }
2539
2540    const VertexBuffer* vertexBuffer = mCaches.tessellationCache.getRoundRect(
2541            *currentTransform(), *p, right - left, bottom - top, rx, ry);
2542    return drawVertexBuffer(left, top, *vertexBuffer, p);
2543}
2544
2545status_t OpenGLRenderer::drawCircle(float x, float y, float radius, const SkPaint* p) {
2546    if (currentSnapshot()->isIgnored()
2547            || quickRejectSetupScissor(x - radius, y - radius, x + radius, y + radius, p)
2548            || paintWillNotDraw(*p)) {
2549        return DrawGlInfo::kStatusDone;
2550    }
2551    if (p->getPathEffect() != 0) {
2552        mCaches.activeTexture(0);
2553        const PathTexture* texture = mCaches.pathCache.getCircle(radius, p);
2554        return drawShape(x - radius, y - radius, texture, p);
2555    }
2556
2557    SkPath path;
2558    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2559        path.addCircle(x, y, radius + p->getStrokeWidth() / 2);
2560    } else {
2561        path.addCircle(x, y, radius);
2562    }
2563    return drawConvexPath(path, p);
2564}
2565
2566status_t OpenGLRenderer::drawOval(float left, float top, float right, float bottom,
2567        const SkPaint* p) {
2568    if (currentSnapshot()->isIgnored()
2569            || quickRejectSetupScissor(left, top, right, bottom, p)
2570            || paintWillNotDraw(*p)) {
2571        return DrawGlInfo::kStatusDone;
2572    }
2573
2574    if (p->getPathEffect() != 0) {
2575        mCaches.activeTexture(0);
2576        const PathTexture* texture = mCaches.pathCache.getOval(right - left, bottom - top, p);
2577        return drawShape(left, top, texture, p);
2578    }
2579
2580    SkPath path;
2581    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2582    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2583        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2584    }
2585    path.addOval(rect);
2586    return drawConvexPath(path, p);
2587}
2588
2589status_t OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2590        float startAngle, float sweepAngle, bool useCenter, const SkPaint* p) {
2591    if (currentSnapshot()->isIgnored()
2592            || quickRejectSetupScissor(left, top, right, bottom, p)
2593            || paintWillNotDraw(*p)) {
2594        return DrawGlInfo::kStatusDone;
2595    }
2596
2597    // TODO: support fills (accounting for concavity if useCenter && sweepAngle > 180)
2598    if (p->getStyle() != SkPaint::kStroke_Style || p->getPathEffect() != 0 || useCenter) {
2599        mCaches.activeTexture(0);
2600        const PathTexture* texture = mCaches.pathCache.getArc(right - left, bottom - top,
2601                startAngle, sweepAngle, useCenter, p);
2602        return drawShape(left, top, texture, p);
2603    }
2604
2605    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2606    if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2607        rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2608    }
2609
2610    SkPath path;
2611    if (useCenter) {
2612        path.moveTo(rect.centerX(), rect.centerY());
2613    }
2614    path.arcTo(rect, startAngle, sweepAngle, !useCenter);
2615    if (useCenter) {
2616        path.close();
2617    }
2618    return drawConvexPath(path, p);
2619}
2620
2621// See SkPaintDefaults.h
2622#define SkPaintDefaults_MiterLimit SkIntToScalar(4)
2623
2624status_t OpenGLRenderer::drawRect(float left, float top, float right, float bottom,
2625        const SkPaint* p) {
2626    if (currentSnapshot()->isIgnored()
2627            || quickRejectSetupScissor(left, top, right, bottom, p)
2628            || paintWillNotDraw(*p)) {
2629        return DrawGlInfo::kStatusDone;
2630    }
2631
2632    if (p->getStyle() != SkPaint::kFill_Style) {
2633        // only fill style is supported by drawConvexPath, since others have to handle joins
2634        if (p->getPathEffect() != 0 || p->getStrokeJoin() != SkPaint::kMiter_Join ||
2635                p->getStrokeMiter() != SkPaintDefaults_MiterLimit) {
2636            mCaches.activeTexture(0);
2637            const PathTexture* texture =
2638                    mCaches.pathCache.getRect(right - left, bottom - top, p);
2639            return drawShape(left, top, texture, p);
2640        }
2641
2642        SkPath path;
2643        SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2644        if (p->getStyle() == SkPaint::kStrokeAndFill_Style) {
2645            rect.outset(p->getStrokeWidth() / 2, p->getStrokeWidth() / 2);
2646        }
2647        path.addRect(rect);
2648        return drawConvexPath(path, p);
2649    }
2650
2651    if (p->isAntiAlias() && !currentTransform()->isSimple()) {
2652        SkPath path;
2653        path.addRect(left, top, right, bottom);
2654        return drawConvexPath(path, p);
2655    } else {
2656        drawColorRect(left, top, right, bottom, p);
2657        return DrawGlInfo::kStatusDrew;
2658    }
2659}
2660
2661void OpenGLRenderer::drawTextShadow(const SkPaint* paint, const char* text,
2662        int bytesCount, int count, const float* positions,
2663        FontRenderer& fontRenderer, int alpha, float x, float y) {
2664    mCaches.activeTexture(0);
2665
2666    TextShadow textShadow;
2667    if (!getTextShadow(paint, &textShadow)) {
2668        LOG_ALWAYS_FATAL("failed to query shadow attributes");
2669    }
2670
2671    // NOTE: The drop shadow will not perform gamma correction
2672    //       if shader-based correction is enabled
2673    mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2674    const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2675            paint, text, bytesCount, count, textShadow.radius, positions);
2676    // If the drop shadow exceeds the max texture size or couldn't be
2677    // allocated, skip drawing
2678    if (!shadow) return;
2679    const AutoTexture autoCleanup(shadow);
2680
2681    const float sx = x - shadow->left + textShadow.dx;
2682    const float sy = y - shadow->top + textShadow.dy;
2683
2684    const int shadowAlpha = ((textShadow.color >> 24) & 0xFF) * mSnapshot->alpha;
2685    if (getShader(paint)) {
2686        textShadow.color = SK_ColorWHITE;
2687    }
2688
2689    setupDraw();
2690    setupDrawWithTexture(true);
2691    setupDrawAlpha8Color(textShadow.color, shadowAlpha < 255 ? shadowAlpha : alpha);
2692    setupDrawColorFilter(getColorFilter(paint));
2693    setupDrawShader(getShader(paint));
2694    setupDrawBlending(paint, true);
2695    setupDrawProgram();
2696    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
2697            sx, sy, sx + shadow->width, sy + shadow->height);
2698    setupDrawTexture(shadow->id);
2699    setupDrawPureColorUniforms();
2700    setupDrawColorFilterUniforms(getColorFilter(paint));
2701    setupDrawShaderUniforms(getShader(paint));
2702    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2703
2704    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2705}
2706
2707bool OpenGLRenderer::canSkipText(const SkPaint* paint) const {
2708    float alpha = (hasTextShadow(paint) ? 1.0f : paint->getAlpha()) * mSnapshot->alpha;
2709    return alpha == 0.0f && getXfermode(paint->getXfermode()) == SkXfermode::kSrcOver_Mode;
2710}
2711
2712status_t OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2713        const float* positions, const SkPaint* paint) {
2714    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2715        return DrawGlInfo::kStatusDone;
2716    }
2717
2718    // NOTE: Skia does not support perspective transform on drawPosText yet
2719    if (!currentTransform()->isSimple()) {
2720        return DrawGlInfo::kStatusDone;
2721    }
2722
2723    mCaches.enableScissor();
2724
2725    float x = 0.0f;
2726    float y = 0.0f;
2727    const bool pureTranslate = currentTransform()->isPureTranslate();
2728    if (pureTranslate) {
2729        x = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2730        y = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2731    }
2732
2733    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2734    fontRenderer.setFont(paint, SkMatrix::I());
2735
2736    int alpha;
2737    SkXfermode::Mode mode;
2738    getAlphaAndMode(paint, &alpha, &mode);
2739
2740    if (CC_UNLIKELY(hasTextShadow(paint))) {
2741        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2742                alpha, 0.0f, 0.0f);
2743    }
2744
2745    // Pick the appropriate texture filtering
2746    bool linearFilter = currentTransform()->changesBounds();
2747    if (pureTranslate && !linearFilter) {
2748        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2749    }
2750    fontRenderer.setTextureFiltering(linearFilter);
2751
2752    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2753    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2754
2755    const bool hasActiveLayer = hasLayer();
2756
2757    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2758    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2759            positions, hasActiveLayer ? &bounds : NULL, &functor)) {
2760        if (hasActiveLayer) {
2761            if (!pureTranslate) {
2762                currentTransform()->mapRect(bounds);
2763            }
2764            dirtyLayerUnchecked(bounds, getRegion());
2765        }
2766    }
2767
2768    return DrawGlInfo::kStatusDrew;
2769}
2770
2771bool OpenGLRenderer::findBestFontTransform(const mat4& transform, SkMatrix* outMatrix) const {
2772    if (CC_LIKELY(transform.isPureTranslate())) {
2773        outMatrix->setIdentity();
2774        return false;
2775    } else if (CC_UNLIKELY(transform.isPerspective())) {
2776        outMatrix->setIdentity();
2777        return true;
2778    }
2779
2780    /**
2781     * Input is a non-perspective, scaling transform. Generate a scale-only transform,
2782     * with values rounded to the nearest int.
2783     */
2784    float sx, sy;
2785    transform.decomposeScale(sx, sy);
2786    outMatrix->setScale(
2787            roundf(fmaxf(1.0f, sx)),
2788            roundf(fmaxf(1.0f, sy)));
2789    return true;
2790}
2791
2792status_t OpenGLRenderer::drawText(const char* text, int bytesCount, int count, float x, float y,
2793        const float* positions, const SkPaint* paint, float totalAdvance, const Rect& bounds,
2794        DrawOpMode drawOpMode) {
2795
2796    if (drawOpMode == kDrawOpMode_Immediate) {
2797        // The checks for corner-case ignorable text and quick rejection is only done for immediate
2798        // drawing as ops from DeferredDisplayList are already filtered for these
2799        if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint) ||
2800                quickRejectSetupScissor(bounds)) {
2801            return DrawGlInfo::kStatusDone;
2802        }
2803    }
2804
2805    const float oldX = x;
2806    const float oldY = y;
2807
2808    const mat4& transform = *currentTransform();
2809    const bool pureTranslate = transform.isPureTranslate();
2810
2811    if (CC_LIKELY(pureTranslate)) {
2812        x = (int) floorf(x + transform.getTranslateX() + 0.5f);
2813        y = (int) floorf(y + transform.getTranslateY() + 0.5f);
2814    }
2815
2816    int alpha;
2817    SkXfermode::Mode mode;
2818    getAlphaAndMode(paint, &alpha, &mode);
2819
2820    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2821
2822    if (CC_UNLIKELY(hasTextShadow(paint))) {
2823        fontRenderer.setFont(paint, SkMatrix::I());
2824        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer,
2825                alpha, oldX, oldY);
2826    }
2827
2828    const bool hasActiveLayer = hasLayer();
2829
2830    // We only pass a partial transform to the font renderer. That partial
2831    // matrix defines how glyphs are rasterized. Typically we want glyphs
2832    // to be rasterized at their final size on screen, which means the partial
2833    // matrix needs to take the scale factor into account.
2834    // When a partial matrix is used to transform glyphs during rasterization,
2835    // the mesh is generated with the inverse transform (in the case of scale,
2836    // the mesh is generated at 1.0 / scale for instance.) This allows us to
2837    // apply the full transform matrix at draw time in the vertex shader.
2838    // Applying the full matrix in the shader is the easiest way to handle
2839    // rotation and perspective and allows us to always generated quads in the
2840    // font renderer which greatly simplifies the code, clipping in particular.
2841    SkMatrix fontTransform;
2842    bool linearFilter = findBestFontTransform(transform, &fontTransform)
2843            || fabs(y - (int) y) > 0.0f
2844            || fabs(x - (int) x) > 0.0f;
2845    fontRenderer.setFont(paint, fontTransform);
2846    fontRenderer.setTextureFiltering(linearFilter);
2847
2848    // TODO: Implement better clipping for scaled/rotated text
2849    const Rect* clip = !pureTranslate ? NULL : currentClipRect();
2850    Rect layerBounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2851
2852    bool status;
2853    TextSetupFunctor functor(this, x, y, pureTranslate, alpha, mode, paint);
2854
2855    // don't call issuedrawcommand, do it at end of batch
2856    bool forceFinish = (drawOpMode != kDrawOpMode_Defer);
2857    if (CC_UNLIKELY(paint->getTextAlign() != SkPaint::kLeft_Align)) {
2858        SkPaint paintCopy(*paint);
2859        paintCopy.setTextAlign(SkPaint::kLeft_Align);
2860        status = fontRenderer.renderPosText(&paintCopy, clip, text, 0, bytesCount, count, x, y,
2861                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2862    } else {
2863        status = fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2864                positions, hasActiveLayer ? &layerBounds : NULL, &functor, forceFinish);
2865    }
2866
2867    if ((status || drawOpMode != kDrawOpMode_Immediate) && hasActiveLayer) {
2868        if (!pureTranslate) {
2869            transform.mapRect(layerBounds);
2870        }
2871        dirtyLayerUnchecked(layerBounds, getRegion());
2872    }
2873
2874    drawTextDecorations(totalAdvance, oldX, oldY, paint);
2875
2876    return DrawGlInfo::kStatusDrew;
2877}
2878
2879status_t OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count,
2880        const SkPath* path, float hOffset, float vOffset, const SkPaint* paint) {
2881    if (text == NULL || count == 0 || currentSnapshot()->isIgnored() || canSkipText(paint)) {
2882        return DrawGlInfo::kStatusDone;
2883    }
2884
2885    // TODO: avoid scissor by calculating maximum bounds using path bounds + font metrics
2886    mCaches.enableScissor();
2887
2888    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2889    fontRenderer.setFont(paint, SkMatrix::I());
2890    fontRenderer.setTextureFiltering(true);
2891
2892    int alpha;
2893    SkXfermode::Mode mode;
2894    getAlphaAndMode(paint, &alpha, &mode);
2895    TextSetupFunctor functor(this, 0.0f, 0.0f, false, alpha, mode, paint);
2896
2897    const Rect* clip = &mSnapshot->getLocalClip();
2898    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2899
2900    const bool hasActiveLayer = hasLayer();
2901
2902    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2903            hOffset, vOffset, hasActiveLayer ? &bounds : NULL, &functor)) {
2904        if (hasActiveLayer) {
2905            currentTransform()->mapRect(bounds);
2906            dirtyLayerUnchecked(bounds, getRegion());
2907        }
2908    }
2909
2910    return DrawGlInfo::kStatusDrew;
2911}
2912
2913status_t OpenGLRenderer::drawPath(const SkPath* path, const SkPaint* paint) {
2914    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
2915
2916    mCaches.activeTexture(0);
2917
2918    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2919    if (!texture) return DrawGlInfo::kStatusDone;
2920    const AutoTexture autoCleanup(texture);
2921
2922    const float x = texture->left - texture->offset;
2923    const float y = texture->top - texture->offset;
2924
2925    drawPathTexture(texture, x, y, paint);
2926
2927    return DrawGlInfo::kStatusDrew;
2928}
2929
2930status_t OpenGLRenderer::drawLayer(Layer* layer, float x, float y) {
2931    if (!layer) {
2932        return DrawGlInfo::kStatusDone;
2933    }
2934
2935    mat4* transform = NULL;
2936    if (layer->isTextureLayer()) {
2937        transform = &layer->getTransform();
2938        if (!transform->isIdentity()) {
2939            save(SkCanvas::kMatrix_SaveFlag);
2940            concatMatrix(*transform);
2941        }
2942    }
2943
2944    bool clipRequired = false;
2945    const bool rejected = calculateQuickRejectForScissor(x, y,
2946            x + layer->layer.getWidth(), y + layer->layer.getHeight(), &clipRequired, NULL, false);
2947
2948    if (rejected) {
2949        if (transform && !transform->isIdentity()) {
2950            restore();
2951        }
2952        return DrawGlInfo::kStatusDone;
2953    }
2954
2955    EVENT_LOGD("drawLayer," RECT_STRING ", clipRequired %d", x, y,
2956            x + layer->layer.getWidth(), y + layer->layer.getHeight(), clipRequired);
2957
2958    updateLayer(layer, true);
2959
2960    mCaches.setScissorEnabled(mScissorOptimizationDisabled || clipRequired);
2961    mCaches.activeTexture(0);
2962
2963    if (CC_LIKELY(!layer->region.isEmpty())) {
2964        if (layer->region.isRect()) {
2965            DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
2966                    composeLayerRect(layer, layer->regionRect));
2967        } else if (layer->mesh) {
2968
2969            const float a = getLayerAlpha(layer);
2970            setupDraw();
2971            setupDrawWithTexture();
2972            setupDrawColor(a, a, a, a);
2973            setupDrawColorFilter(layer->getColorFilter());
2974            setupDrawBlending(layer);
2975            setupDrawProgram();
2976            setupDrawPureColorUniforms();
2977            setupDrawColorFilterUniforms(layer->getColorFilter());
2978            setupDrawTexture(layer->getTexture());
2979            if (CC_LIKELY(currentTransform()->isPureTranslate())) {
2980                int tx = (int) floorf(x + currentTransform()->getTranslateX() + 0.5f);
2981                int ty = (int) floorf(y + currentTransform()->getTranslateY() + 0.5f);
2982
2983                layer->setFilter(GL_NEAREST);
2984                setupDrawModelView(kModelViewMode_Translate, false, tx, ty,
2985                        tx + layer->layer.getWidth(), ty + layer->layer.getHeight(), true);
2986            } else {
2987                layer->setFilter(GL_LINEAR);
2988                setupDrawModelView(kModelViewMode_Translate, false, x, y,
2989                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
2990            }
2991
2992            TextureVertex* mesh = &layer->mesh[0];
2993            GLsizei elementsCount = layer->meshElementCount;
2994
2995            while (elementsCount > 0) {
2996                GLsizei drawCount = min(elementsCount, (GLsizei) gMaxNumberOfQuads * 6);
2997
2998                setupDrawMeshIndices(&mesh[0].x, &mesh[0].u);
2999                DRAW_DOUBLE_STENCIL_IF(!layer->hasDrawnSinceUpdate,
3000                        glDrawElements(GL_TRIANGLES, drawCount, GL_UNSIGNED_SHORT, NULL));
3001
3002                elementsCount -= drawCount;
3003                // Though there are 4 vertices in a quad, we use 6 indices per
3004                // quad to draw with GL_TRIANGLES
3005                mesh += (drawCount / 6) * 4;
3006            }
3007
3008#if DEBUG_LAYERS_AS_REGIONS
3009            drawRegionRectsDebug(layer->region);
3010#endif
3011        }
3012
3013        if (layer->debugDrawUpdate) {
3014            layer->debugDrawUpdate = false;
3015
3016            SkPaint paint;
3017            paint.setColor(0x7f00ff00);
3018            drawColorRect(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight(), &paint);
3019        }
3020    }
3021    layer->hasDrawnSinceUpdate = true;
3022
3023    if (transform && !transform->isIdentity()) {
3024        restore();
3025    }
3026
3027    return DrawGlInfo::kStatusDrew;
3028}
3029
3030///////////////////////////////////////////////////////////////////////////////
3031// Draw filters
3032///////////////////////////////////////////////////////////////////////////////
3033
3034void OpenGLRenderer::resetPaintFilter() {
3035    // when clearing the PaintFilter, the masks should also be cleared for simple DrawModifier
3036    // comparison, see MergingDrawBatch::canMergeWith
3037    mDrawModifiers.mHasDrawFilter = false;
3038    mDrawModifiers.mPaintFilterClearBits = 0;
3039    mDrawModifiers.mPaintFilterSetBits = 0;
3040}
3041
3042void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
3043    // TODO: don't bother with boolean, it's redundant with clear/set bits
3044    mDrawModifiers.mHasDrawFilter = true;
3045    mDrawModifiers.mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
3046    mDrawModifiers.mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
3047}
3048
3049const SkPaint* OpenGLRenderer::filterPaint(const SkPaint* paint) {
3050    // TODO: use CompatFlagsDrawFilter here, and combine logic with android/graphics/DrawFilter.cpp
3051    // to avoid clobbering 0x02 paint flag
3052
3053    // Equivalent to the Java Paint's FILTER_BITMAP_FLAG.
3054    static const uint32_t sFilterBitmapFlag = 0x02;
3055
3056    if (CC_LIKELY(!mDrawModifiers.mHasDrawFilter || !paint)) {
3057        return paint;
3058    }
3059
3060    const uint32_t clearBits = mDrawModifiers.mPaintFilterClearBits;
3061    const uint32_t setBits = mDrawModifiers.mPaintFilterSetBits;
3062
3063    const uint32_t flags = (paint->getFlags() & ~clearBits) | setBits;
3064    mFilteredPaint = *paint;
3065    mFilteredPaint.setFlags(flags);
3066
3067    // check if paint filter trying to override bitmap filter
3068    if ((clearBits | setBits) & sFilterBitmapFlag) {
3069        mFilteredPaint.setFilterLevel(flags & sFilterBitmapFlag
3070                ? SkPaint::kLow_FilterLevel : SkPaint::kNone_FilterLevel);
3071    }
3072
3073    return &mFilteredPaint;
3074}
3075
3076///////////////////////////////////////////////////////////////////////////////
3077// Drawing implementation
3078///////////////////////////////////////////////////////////////////////////////
3079
3080Texture* OpenGLRenderer::getTexture(const SkBitmap* bitmap) {
3081    Texture* texture = mCaches.assetAtlas.getEntryTexture(bitmap);
3082    if (!texture) {
3083        return mCaches.textureCache.get(bitmap);
3084    }
3085    return texture;
3086}
3087
3088void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
3089        float x, float y, const SkPaint* paint) {
3090    if (quickRejectSetupScissor(x, y, x + texture->width, y + texture->height)) {
3091        return;
3092    }
3093
3094    int alpha;
3095    SkXfermode::Mode mode;
3096    getAlphaAndMode(paint, &alpha, &mode);
3097
3098    setupDraw();
3099    setupDrawWithTexture(true);
3100    setupDrawAlpha8Color(paint->getColor(), alpha);
3101    setupDrawColorFilter(getColorFilter(paint));
3102    setupDrawShader(getShader(paint));
3103    setupDrawBlending(paint, true);
3104    setupDrawProgram();
3105    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3106            x, y, x + texture->width, y + texture->height);
3107    setupDrawTexture(texture->id);
3108    setupDrawPureColorUniforms();
3109    setupDrawColorFilterUniforms(getColorFilter(paint));
3110    setupDrawShaderUniforms(getShader(paint));
3111    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
3112
3113    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3114}
3115
3116// Same values used by Skia
3117#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
3118#define kStdUnderline_Offset    (1.0f / 9.0f)
3119#define kStdUnderline_Thickness (1.0f / 18.0f)
3120
3121void OpenGLRenderer::drawTextDecorations(float underlineWidth, float x, float y,
3122        const SkPaint* paint) {
3123    // Handle underline and strike-through
3124    uint32_t flags = paint->getFlags();
3125    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
3126        SkPaint paintCopy(*paint);
3127
3128        if (CC_LIKELY(underlineWidth > 0.0f)) {
3129            const float textSize = paintCopy.getTextSize();
3130            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
3131
3132            const float left = x;
3133            float top = 0.0f;
3134
3135            int linesCount = 0;
3136            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
3137            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
3138
3139            const int pointsCount = 4 * linesCount;
3140            float points[pointsCount];
3141            int currentPoint = 0;
3142
3143            if (flags & SkPaint::kUnderlineText_Flag) {
3144                top = y + textSize * kStdUnderline_Offset;
3145                points[currentPoint++] = left;
3146                points[currentPoint++] = top;
3147                points[currentPoint++] = left + underlineWidth;
3148                points[currentPoint++] = top;
3149            }
3150
3151            if (flags & SkPaint::kStrikeThruText_Flag) {
3152                top = y + textSize * kStdStrikeThru_Offset;
3153                points[currentPoint++] = left;
3154                points[currentPoint++] = top;
3155                points[currentPoint++] = left + underlineWidth;
3156                points[currentPoint++] = top;
3157            }
3158
3159            paintCopy.setStrokeWidth(strokeWidth);
3160
3161            drawLines(&points[0], pointsCount, &paintCopy);
3162        }
3163    }
3164}
3165
3166status_t OpenGLRenderer::drawRects(const float* rects, int count, const SkPaint* paint) {
3167    if (currentSnapshot()->isIgnored()) {
3168        return DrawGlInfo::kStatusDone;
3169    }
3170
3171    return drawColorRects(rects, count, paint, false, true, true);
3172}
3173
3174static void mapPointFakeZ(Vector3& point, const mat4& transformXY, const mat4& transformZ) {
3175    // map z coordinate with true 3d matrix
3176    point.z = transformZ.mapZ(point);
3177
3178    // map x,y coordinates with draw/Skia matrix
3179    transformXY.mapPoint(point.x, point.y);
3180}
3181
3182status_t OpenGLRenderer::drawShadow(float casterAlpha,
3183        const VertexBuffer* ambientShadowVertexBuffer, const VertexBuffer* spotShadowVertexBuffer) {
3184    if (currentSnapshot()->isIgnored()) return DrawGlInfo::kStatusDone;
3185
3186    // TODO: use quickRejectWithScissor. For now, always force enable scissor.
3187    mCaches.enableScissor();
3188
3189    SkPaint paint;
3190    paint.setAntiAlias(true); // want to use AlphaVertex
3191
3192    // The caller has made sure casterAlpha > 0.
3193    float ambientShadowAlpha = mAmbientShadowAlpha;
3194    if (CC_UNLIKELY(mCaches.propertyAmbientShadowStrength >= 0)) {
3195        ambientShadowAlpha = mCaches.propertyAmbientShadowStrength;
3196    }
3197    if (ambientShadowVertexBuffer && ambientShadowAlpha > 0) {
3198        paint.setARGB(casterAlpha * ambientShadowAlpha, 0, 0, 0);
3199        drawVertexBuffer(*ambientShadowVertexBuffer, &paint, kVertexBuffer_ShadowInterp);
3200    }
3201
3202    float spotShadowAlpha = mSpotShadowAlpha;
3203    if (CC_UNLIKELY(mCaches.propertySpotShadowStrength >= 0)) {
3204        spotShadowAlpha = mCaches.propertySpotShadowStrength;
3205    }
3206    if (spotShadowVertexBuffer && spotShadowAlpha > 0) {
3207        paint.setARGB(casterAlpha * spotShadowAlpha, 0, 0, 0);
3208        drawVertexBuffer(*spotShadowVertexBuffer, &paint, kVertexBuffer_ShadowInterp);
3209    }
3210
3211    return DrawGlInfo::kStatusDrew;
3212}
3213
3214status_t OpenGLRenderer::drawColorRects(const float* rects, int count, const SkPaint* paint,
3215        bool ignoreTransform, bool dirty, bool clip) {
3216    if (count == 0) {
3217        return DrawGlInfo::kStatusDone;
3218    }
3219
3220    int color = paint->getColor();
3221    // If a shader is set, preserve only the alpha
3222    if (getShader(paint)) {
3223        color |= 0x00ffffff;
3224    }
3225
3226    float left = FLT_MAX;
3227    float top = FLT_MAX;
3228    float right = FLT_MIN;
3229    float bottom = FLT_MIN;
3230
3231    Vertex mesh[count];
3232    Vertex* vertex = mesh;
3233
3234    for (int index = 0; index < count; index += 4) {
3235        float l = rects[index + 0];
3236        float t = rects[index + 1];
3237        float r = rects[index + 2];
3238        float b = rects[index + 3];
3239
3240        Vertex::set(vertex++, l, t);
3241        Vertex::set(vertex++, r, t);
3242        Vertex::set(vertex++, l, b);
3243        Vertex::set(vertex++, r, b);
3244
3245        left = fminf(left, l);
3246        top = fminf(top, t);
3247        right = fmaxf(right, r);
3248        bottom = fmaxf(bottom, b);
3249    }
3250
3251    if (clip && quickRejectSetupScissor(left, top, right, bottom)) {
3252        return DrawGlInfo::kStatusDone;
3253    }
3254
3255    setupDraw();
3256    setupDrawNoTexture();
3257    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3258    setupDrawShader(getShader(paint));
3259    setupDrawColorFilter(getColorFilter(paint));
3260    setupDrawBlending(paint);
3261    setupDrawProgram();
3262    setupDrawDirtyRegionsDisabled();
3263    setupDrawModelView(kModelViewMode_Translate, false,
3264            0.0f, 0.0f, 0.0f, 0.0f, ignoreTransform);
3265    setupDrawColorUniforms(getShader(paint));
3266    setupDrawShaderUniforms(getShader(paint));
3267    setupDrawColorFilterUniforms(getColorFilter(paint));
3268
3269    if (dirty && hasLayer()) {
3270        dirtyLayer(left, top, right, bottom, *currentTransform());
3271    }
3272
3273    issueIndexedQuadDraw(&mesh[0], count / 4);
3274
3275    return DrawGlInfo::kStatusDrew;
3276}
3277
3278void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
3279        const SkPaint* paint, bool ignoreTransform) {
3280    int color = paint->getColor();
3281    // If a shader is set, preserve only the alpha
3282    if (getShader(paint)) {
3283        color |= 0x00ffffff;
3284    }
3285
3286    setupDraw();
3287    setupDrawNoTexture();
3288    setupDrawColor(color, ((color >> 24) & 0xFF) * currentSnapshot()->alpha);
3289    setupDrawShader(getShader(paint));
3290    setupDrawColorFilter(getColorFilter(paint));
3291    setupDrawBlending(paint);
3292    setupDrawProgram();
3293    setupDrawModelView(kModelViewMode_TranslateAndScale, false,
3294            left, top, right, bottom, ignoreTransform);
3295    setupDrawColorUniforms(getShader(paint));
3296    setupDrawShaderUniforms(getShader(paint), ignoreTransform);
3297    setupDrawColorFilterUniforms(getColorFilter(paint));
3298    setupDrawSimpleMesh();
3299
3300    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
3301}
3302
3303void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
3304        Texture* texture, const SkPaint* paint) {
3305    texture->setWrap(GL_CLAMP_TO_EDGE, true);
3306
3307    GLvoid* vertices = (GLvoid*) NULL;
3308    GLvoid* texCoords = (GLvoid*) gMeshTextureOffset;
3309
3310    if (texture->uvMapper) {
3311        vertices = &mMeshVertices[0].x;
3312        texCoords = &mMeshVertices[0].u;
3313
3314        Rect uvs(0.0f, 0.0f, 1.0f, 1.0f);
3315        texture->uvMapper->map(uvs);
3316
3317        resetDrawTextureTexCoords(uvs.left, uvs.top, uvs.right, uvs.bottom);
3318    }
3319
3320    if (CC_LIKELY(currentTransform()->isPureTranslate())) {
3321        const float x = (int) floorf(left + currentTransform()->getTranslateX() + 0.5f);
3322        const float y = (int) floorf(top + currentTransform()->getTranslateY() + 0.5f);
3323
3324        texture->setFilter(GL_NEAREST, true);
3325        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
3326                paint, texture->blend, vertices, texCoords,
3327                GL_TRIANGLE_STRIP, gMeshCount, false, true);
3328    } else {
3329        texture->setFilter(getFilter(paint), true);
3330        drawTextureMesh(left, top, right, bottom, texture->id, paint,
3331                texture->blend, vertices, texCoords, GL_TRIANGLE_STRIP, gMeshCount);
3332    }
3333
3334    if (texture->uvMapper) {
3335        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
3336    }
3337}
3338
3339void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
3340        GLuint texture, const SkPaint* paint, bool blend,
3341        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3342        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3343        ModelViewMode modelViewMode, bool dirty) {
3344
3345    int a;
3346    SkXfermode::Mode mode;
3347    getAlphaAndMode(paint, &a, &mode);
3348    const float alpha = a / 255.0f;
3349
3350    setupDraw();
3351    setupDrawWithTexture();
3352    setupDrawColor(alpha, alpha, alpha, alpha);
3353    setupDrawColorFilter(getColorFilter(paint));
3354    setupDrawBlending(paint, blend, swapSrcDst);
3355    setupDrawProgram();
3356    if (!dirty) setupDrawDirtyRegionsDisabled();
3357    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3358    setupDrawTexture(texture);
3359    setupDrawPureColorUniforms();
3360    setupDrawColorFilterUniforms(getColorFilter(paint));
3361    setupDrawMesh(vertices, texCoords, vbo);
3362
3363    glDrawArrays(drawMode, 0, elementsCount);
3364}
3365
3366void OpenGLRenderer::drawIndexedTextureMesh(float left, float top, float right, float bottom,
3367        GLuint texture, const SkPaint* paint, bool blend,
3368        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3369        bool swapSrcDst, bool ignoreTransform, GLuint vbo,
3370        ModelViewMode modelViewMode, bool dirty) {
3371
3372    int a;
3373    SkXfermode::Mode mode;
3374    getAlphaAndMode(paint, &a, &mode);
3375    const float alpha = a / 255.0f;
3376
3377    setupDraw();
3378    setupDrawWithTexture();
3379    setupDrawColor(alpha, alpha, alpha, alpha);
3380    setupDrawColorFilter(getColorFilter(paint));
3381    setupDrawBlending(paint, blend, swapSrcDst);
3382    setupDrawProgram();
3383    if (!dirty) setupDrawDirtyRegionsDisabled();
3384    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3385    setupDrawTexture(texture);
3386    setupDrawPureColorUniforms();
3387    setupDrawColorFilterUniforms(getColorFilter(paint));
3388    setupDrawMeshIndices(vertices, texCoords, vbo);
3389
3390    glDrawElements(drawMode, elementsCount, GL_UNSIGNED_SHORT, NULL);
3391}
3392
3393void OpenGLRenderer::drawAlpha8TextureMesh(float left, float top, float right, float bottom,
3394        GLuint texture, const SkPaint* paint,
3395        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3396        bool ignoreTransform, ModelViewMode modelViewMode, bool dirty) {
3397
3398    int color = paint != NULL ? paint->getColor() : 0;
3399    int alpha;
3400    SkXfermode::Mode mode;
3401    getAlphaAndMode(paint, &alpha, &mode);
3402
3403    setupDraw();
3404    setupDrawWithTexture(true);
3405    if (paint != NULL) {
3406        setupDrawAlpha8Color(color, alpha);
3407    }
3408    setupDrawColorFilter(getColorFilter(paint));
3409    setupDrawShader(getShader(paint));
3410    setupDrawBlending(paint, true);
3411    setupDrawProgram();
3412    if (!dirty) setupDrawDirtyRegionsDisabled();
3413    setupDrawModelView(modelViewMode, false, left, top, right, bottom, ignoreTransform);
3414    setupDrawTexture(texture);
3415    setupDrawPureColorUniforms();
3416    setupDrawColorFilterUniforms(getColorFilter(paint));
3417    setupDrawShaderUniforms(getShader(paint), ignoreTransform);
3418    setupDrawMesh(vertices, texCoords);
3419
3420    glDrawArrays(drawMode, 0, elementsCount);
3421}
3422
3423void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
3424        ProgramDescription& description, bool swapSrcDst) {
3425
3426    if (mSnapshot->roundRectClipState != NULL /*&& !mSkipOutlineClip*/) {
3427        blend = true;
3428        mDescription.hasRoundRectClip = true;
3429    }
3430    mSkipOutlineClip = true;
3431
3432    if (mCountOverdraw) {
3433        if (!mCaches.blend) glEnable(GL_BLEND);
3434        if (mCaches.lastSrcMode != GL_ONE || mCaches.lastDstMode != GL_ONE) {
3435            glBlendFunc(GL_ONE, GL_ONE);
3436        }
3437
3438        mCaches.blend = true;
3439        mCaches.lastSrcMode = GL_ONE;
3440        mCaches.lastDstMode = GL_ONE;
3441
3442        return;
3443    }
3444
3445    blend = blend || mode != SkXfermode::kSrcOver_Mode;
3446
3447    if (blend) {
3448        // These blend modes are not supported by OpenGL directly and have
3449        // to be implemented using shaders. Since the shader will perform
3450        // the blending, turn blending off here
3451        // If the blend mode cannot be implemented using shaders, fall
3452        // back to the default SrcOver blend mode instead
3453        if (CC_UNLIKELY(mode > SkXfermode::kScreen_Mode)) {
3454            if (CC_UNLIKELY(mExtensions.hasFramebufferFetch())) {
3455                description.framebufferMode = mode;
3456                description.swapSrcDst = swapSrcDst;
3457
3458                if (mCaches.blend) {
3459                    glDisable(GL_BLEND);
3460                    mCaches.blend = false;
3461                }
3462
3463                return;
3464            } else {
3465                mode = SkXfermode::kSrcOver_Mode;
3466            }
3467        }
3468
3469        if (!mCaches.blend) {
3470            glEnable(GL_BLEND);
3471        }
3472
3473        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
3474        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
3475
3476        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
3477            glBlendFunc(sourceMode, destMode);
3478            mCaches.lastSrcMode = sourceMode;
3479            mCaches.lastDstMode = destMode;
3480        }
3481    } else if (mCaches.blend) {
3482        glDisable(GL_BLEND);
3483    }
3484    mCaches.blend = blend;
3485}
3486
3487bool OpenGLRenderer::useProgram(Program* program) {
3488    if (!program->isInUse()) {
3489        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
3490        program->use();
3491        mCaches.currentProgram = program;
3492        return false;
3493    }
3494    return true;
3495}
3496
3497void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
3498    TextureVertex* v = &mMeshVertices[0];
3499    TextureVertex::setUV(v++, u1, v1);
3500    TextureVertex::setUV(v++, u2, v1);
3501    TextureVertex::setUV(v++, u1, v2);
3502    TextureVertex::setUV(v++, u2, v2);
3503}
3504
3505void OpenGLRenderer::getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode) const {
3506    getAlphaAndModeDirect(paint, alpha,  mode);
3507    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3508        // if drawing a layer, ignore the paint's alpha
3509        *alpha = mDrawModifiers.mOverrideLayerAlpha * 255;
3510    }
3511    *alpha *= currentSnapshot()->alpha;
3512}
3513
3514float OpenGLRenderer::getLayerAlpha(const Layer* layer) const {
3515    float alpha;
3516    if (mDrawModifiers.mOverrideLayerAlpha < 1.0f) {
3517        alpha = mDrawModifiers.mOverrideLayerAlpha;
3518    } else {
3519        alpha = layer->getAlpha() / 255.0f;
3520    }
3521    return alpha * currentSnapshot()->alpha;
3522}
3523
3524}; // namespace uirenderer
3525}; // namespace android
3526