OpenGLRenderer.cpp revision 54c1a64d5441a964890b44280e4457e11f4f924a 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkPathMeasure.h>
25#include <SkTypeface.h>
26
27#include <utils/Log.h>
28#include <utils/StopWatch.h>
29
30#include <private/hwui/DrawGlInfo.h>
31
32#include <ui/Rect.h>
33
34#include "OpenGLRenderer.h"
35#include "DisplayListRenderer.h"
36#include "PathRenderer.h"
37#include "Properties.h"
38#include "Vector.h"
39
40namespace android {
41namespace uirenderer {
42
43///////////////////////////////////////////////////////////////////////////////
44// Defines
45///////////////////////////////////////////////////////////////////////////////
46
47#define RAD_TO_DEG (180.0f / 3.14159265f)
48#define MIN_ANGLE 0.001f
49
50#define ALPHA_THRESHOLD 0
51
52#define FILTER(paint) (paint && paint->isFilterBitmap() ? GL_LINEAR : GL_NEAREST)
53
54///////////////////////////////////////////////////////////////////////////////
55// Globals
56///////////////////////////////////////////////////////////////////////////////
57
58/**
59 * Structure mapping Skia xfermodes to OpenGL blending factors.
60 */
61struct Blender {
62    SkXfermode::Mode mode;
63    GLenum src;
64    GLenum dst;
65}; // struct Blender
66
67// In this array, the index of each Blender equals the value of the first
68// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
69static const Blender gBlends[] = {
70    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
71    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
72    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
73    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
74    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
75    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
76    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
77    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
78    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
79    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
80    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
81    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
82    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
83    { SkXfermode::kMultiply_Mode, GL_ZERO,                GL_SRC_COLOR },
84    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
85};
86
87// This array contains the swapped version of each SkXfermode. For instance
88// this array's SrcOver blending mode is actually DstOver. You can refer to
89// createLayer() for more information on the purpose of this array.
90static const Blender gBlendsSwap[] = {
91    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
92    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
93    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
94    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
95    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
96    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
97    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
98    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
99    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
100    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
101    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
102    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
103    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
104    { SkXfermode::kMultiply_Mode, GL_DST_COLOR,           GL_ZERO },
105    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
106};
107
108///////////////////////////////////////////////////////////////////////////////
109// Constructors/destructor
110///////////////////////////////////////////////////////////////////////////////
111
112OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
113    mShader = NULL;
114    mColorFilter = NULL;
115    mHasShadow = false;
116    mHasDrawFilter = false;
117
118    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
119
120    mFirstSnapshot = new Snapshot;
121
122    mScissorOptimizationDisabled = false;
123}
124
125OpenGLRenderer::~OpenGLRenderer() {
126    // The context has already been destroyed at this point, do not call
127    // GL APIs. All GL state should be kept in Caches.h
128}
129
130void OpenGLRenderer::initProperties() {
131    char property[PROPERTY_VALUE_MAX];
132    if (property_get(PROPERTY_DISABLE_SCISSOR_OPTIMIZATION, property, "false")) {
133        mScissorOptimizationDisabled = !strcasecmp(property, "true");
134        INIT_LOGD("  Scissor optimization %s",
135                mScissorOptimizationDisabled ? "disabled" : "enabled");
136    } else {
137        INIT_LOGD("  Scissor optimization enabled");
138    }
139}
140
141///////////////////////////////////////////////////////////////////////////////
142// Setup
143///////////////////////////////////////////////////////////////////////////////
144
145bool OpenGLRenderer::isDeferred() {
146    return false;
147}
148
149void OpenGLRenderer::setViewport(int width, int height) {
150    initViewport(width, height);
151
152    glDisable(GL_DITHER);
153    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
154
155    glEnableVertexAttribArray(Program::kBindingPosition);
156}
157
158void OpenGLRenderer::initViewport(int width, int height) {
159    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
160
161    mWidth = width;
162    mHeight = height;
163
164    mFirstSnapshot->height = height;
165    mFirstSnapshot->viewport.set(0, 0, width, height);
166}
167
168int OpenGLRenderer::prepare(bool opaque) {
169    return prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
170}
171
172int OpenGLRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
173    mCaches.clearGarbage();
174
175    mSnapshot = new Snapshot(mFirstSnapshot,
176            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
177    mSnapshot->fbo = getTargetFbo();
178    mSaveCount = 1;
179
180    mSnapshot->setClip(left, top, right, bottom);
181    mDirtyClip = opaque;
182
183    updateLayers();
184
185    // If we know that we are going to redraw the entire framebuffer,
186    // perform a discard to let the driver know we don't need to preserve
187    // the back buffer for this frame.
188    if (mCaches.extensions.hasDiscardFramebuffer() &&
189            left <= 0.0f && top <= 0.0f && right >= mWidth && bottom >= mHeight) {
190        const GLenum attachments[] = { getTargetFbo() == 0 ? GL_COLOR_EXT : GL_COLOR_ATTACHMENT0 };
191        glDiscardFramebufferEXT(GL_FRAMEBUFFER, 1, attachments);
192    }
193
194    syncState();
195
196    // Functors break the tiling extension in pretty spectacular ways
197    // This ensures we don't use tiling when a functor is going to be
198    // invoked during the frame
199    mSuppressTiling = mCaches.hasRegisteredFunctors();
200
201    mTilingSnapshot = mSnapshot;
202    startTiling(mTilingSnapshot, true);
203
204    debugOverdraw(true, true);
205
206    if (!opaque) {
207        mCaches.enableScissor();
208        mCaches.setScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
209        glClear(GL_COLOR_BUFFER_BIT);
210        return DrawGlInfo::kStatusDrew;
211    } else {
212        mCaches.resetScissor();
213    }
214
215    return DrawGlInfo::kStatusDone;
216}
217
218void OpenGLRenderer::syncState() {
219    glViewport(0, 0, mWidth, mHeight);
220
221    if (mCaches.blend) {
222        glEnable(GL_BLEND);
223    } else {
224        glDisable(GL_BLEND);
225    }
226}
227
228void OpenGLRenderer::startTiling(const sp<Snapshot>& s, bool opaque) {
229    if (!mSuppressTiling) {
230        Rect* clip = mTilingSnapshot->clipRect;
231        if (s->flags & Snapshot::kFlagIsFboLayer) {
232            clip = s->clipRect;
233        }
234
235        mCaches.startTiling(clip->left, s->height - clip->bottom,
236                clip->right - clip->left, clip->bottom - clip->top, opaque);
237    }
238}
239
240void OpenGLRenderer::endTiling() {
241    if (!mSuppressTiling) mCaches.endTiling();
242}
243
244void OpenGLRenderer::finish() {
245    renderOverdraw();
246    endTiling();
247
248    if (!suppressErrorChecks()) {
249#if DEBUG_OPENGL
250        GLenum status = GL_NO_ERROR;
251        while ((status = glGetError()) != GL_NO_ERROR) {
252            ALOGD("GL error from OpenGLRenderer: 0x%x", status);
253            switch (status) {
254                case GL_INVALID_ENUM:
255                    ALOGE("  GL_INVALID_ENUM");
256                    break;
257                case GL_INVALID_VALUE:
258                    ALOGE("  GL_INVALID_VALUE");
259                    break;
260                case GL_INVALID_OPERATION:
261                    ALOGE("  GL_INVALID_OPERATION");
262                    break;
263                case GL_OUT_OF_MEMORY:
264                    ALOGE("  Out of memory!");
265                    break;
266            }
267        }
268#endif
269
270#if DEBUG_MEMORY_USAGE
271        mCaches.dumpMemoryUsage();
272#else
273        if (mCaches.getDebugLevel() & kDebugMemory) {
274            mCaches.dumpMemoryUsage();
275        }
276#endif
277    }
278}
279
280void OpenGLRenderer::interrupt() {
281    if (mCaches.currentProgram) {
282        if (mCaches.currentProgram->isInUse()) {
283            mCaches.currentProgram->remove();
284            mCaches.currentProgram = NULL;
285        }
286    }
287    mCaches.unbindMeshBuffer();
288    mCaches.unbindIndicesBuffer();
289    mCaches.resetVertexPointers();
290    mCaches.disbaleTexCoordsVertexArray();
291    debugOverdraw(false, false);
292}
293
294void OpenGLRenderer::resume() {
295    sp<Snapshot> snapshot = (mSnapshot != NULL) ? mSnapshot : mFirstSnapshot;
296    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
297    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
298    debugOverdraw(true, false);
299
300    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
301
302    mCaches.scissorEnabled = glIsEnabled(GL_SCISSOR_TEST);
303    mCaches.enableScissor();
304    mCaches.resetScissor();
305    dirtyClip();
306
307    mCaches.activeTexture(0);
308
309    mCaches.blend = true;
310    glEnable(GL_BLEND);
311    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
312    glBlendEquation(GL_FUNC_ADD);
313}
314
315void OpenGLRenderer::resumeAfterLayer() {
316    sp<Snapshot> snapshot = (mSnapshot != NULL) ? mSnapshot : mFirstSnapshot;
317    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
318    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
319    debugOverdraw(true, false);
320
321    mCaches.resetScissor();
322    dirtyClip();
323}
324
325void OpenGLRenderer::detachFunctor(Functor* functor) {
326    mFunctors.remove(functor);
327}
328
329void OpenGLRenderer::attachFunctor(Functor* functor) {
330    mFunctors.add(functor);
331}
332
333status_t OpenGLRenderer::invokeFunctors(Rect& dirty) {
334    status_t result = DrawGlInfo::kStatusDone;
335    size_t count = mFunctors.size();
336
337    if (count > 0) {
338        SortedVector<Functor*> functors(mFunctors);
339        mFunctors.clear();
340
341        DrawGlInfo info;
342        info.clipLeft = 0;
343        info.clipTop = 0;
344        info.clipRight = 0;
345        info.clipBottom = 0;
346        info.isLayer = false;
347        info.width = 0;
348        info.height = 0;
349        memset(info.transform, 0, sizeof(float) * 16);
350
351        for (size_t i = 0; i < count; i++) {
352            Functor* f = functors.itemAt(i);
353            result |= (*f)(DrawGlInfo::kModeProcess, &info);
354
355            if (result & DrawGlInfo::kStatusDraw) {
356                Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
357                dirty.unionWith(localDirty);
358            }
359
360            if (result & DrawGlInfo::kStatusInvoke) {
361                mFunctors.add(f);
362            }
363        }
364        // protect against functors binding to other buffers
365        mCaches.unbindMeshBuffer();
366        mCaches.unbindIndicesBuffer();
367        mCaches.activeTexture(0);
368    }
369
370    return result;
371}
372
373status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
374    interrupt();
375    detachFunctor(functor);
376
377    mCaches.enableScissor();
378    if (mDirtyClip) {
379        setScissorFromClip();
380    }
381
382    Rect clip(*mSnapshot->clipRect);
383    clip.snapToPixelBoundaries();
384
385    // Since we don't know what the functor will draw, let's dirty
386    // tne entire clip region
387    if (hasLayer()) {
388        dirtyLayerUnchecked(clip, getRegion());
389    }
390
391    DrawGlInfo info;
392    info.clipLeft = clip.left;
393    info.clipTop = clip.top;
394    info.clipRight = clip.right;
395    info.clipBottom = clip.bottom;
396    info.isLayer = hasLayer();
397    info.width = getSnapshot()->viewport.getWidth();
398    info.height = getSnapshot()->height;
399    getSnapshot()->transform->copyTo(&info.transform[0]);
400
401    status_t result = (*functor)(DrawGlInfo::kModeDraw, &info) | DrawGlInfo::kStatusDrew;
402
403    if (result != DrawGlInfo::kStatusDone) {
404        Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
405        dirty.unionWith(localDirty);
406
407        if (result & DrawGlInfo::kStatusInvoke) {
408            mFunctors.add(functor);
409        }
410    }
411
412    resume();
413    return result;
414}
415
416///////////////////////////////////////////////////////////////////////////////
417// Debug
418///////////////////////////////////////////////////////////////////////////////
419
420void OpenGLRenderer::startMark(const char* name) const {
421    mCaches.startMark(0, name);
422}
423
424void OpenGLRenderer::endMark() const {
425    mCaches.endMark();
426}
427
428void OpenGLRenderer::debugOverdraw(bool enable, bool clear) {
429    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
430        if (clear) {
431            mCaches.disableScissor();
432            mCaches.stencil.clear();
433        }
434        if (enable) {
435            mCaches.stencil.enableDebugWrite();
436        } else {
437            mCaches.stencil.disable();
438        }
439    }
440}
441
442void OpenGLRenderer::renderOverdraw() {
443    if (mCaches.debugOverdraw && getTargetFbo() == 0) {
444        const Rect* clip = mTilingSnapshot->clipRect;
445
446        mCaches.enableScissor();
447        mCaches.setScissor(clip->left, mTilingSnapshot->height - clip->bottom,
448                clip->right - clip->left, clip->bottom - clip->top);
449
450        mCaches.stencil.enableDebugTest(2);
451        drawColor(0x2f0000ff, SkXfermode::kSrcOver_Mode);
452        mCaches.stencil.enableDebugTest(3);
453        drawColor(0x2f00ff00, SkXfermode::kSrcOver_Mode);
454        mCaches.stencil.enableDebugTest(4);
455        drawColor(0x3fff0000, SkXfermode::kSrcOver_Mode);
456        mCaches.stencil.enableDebugTest(4, true);
457        drawColor(0x7fff0000, SkXfermode::kSrcOver_Mode);
458        mCaches.stencil.disable();
459    }
460}
461
462///////////////////////////////////////////////////////////////////////////////
463// Layers
464///////////////////////////////////////////////////////////////////////////////
465
466bool OpenGLRenderer::updateLayer(Layer* layer, bool inFrame) {
467    if (layer->deferredUpdateScheduled && layer->renderer && layer->displayList) {
468        OpenGLRenderer* renderer = layer->renderer;
469        Rect& dirty = layer->dirtyRect;
470
471        if (inFrame) {
472            endTiling();
473            debugOverdraw(false, false);
474        }
475
476        renderer->setViewport(layer->layer.getWidth(), layer->layer.getHeight());
477        renderer->prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, !layer->isBlend());
478        renderer->drawDisplayList(layer->displayList, dirty, DisplayList::kReplayFlag_ClipChildren);
479        renderer->finish();
480
481        if (inFrame) {
482            resumeAfterLayer();
483            startTiling(mSnapshot);
484        }
485
486        dirty.setEmpty();
487        layer->deferredUpdateScheduled = false;
488        layer->renderer = NULL;
489        layer->displayList = NULL;
490
491        return true;
492    }
493
494    return false;
495}
496
497void OpenGLRenderer::updateLayers() {
498    int count = mLayerUpdates.size();
499    if (count > 0) {
500        startMark("Layer Updates");
501
502        // Note: it is very important to update the layers in reverse order
503        for (int i = count - 1; i >= 0; i--) {
504            Layer* layer = mLayerUpdates.itemAt(i);
505            updateLayer(layer, false);
506            mCaches.resourceCache.decrementRefcount(layer);
507        }
508        mLayerUpdates.clear();
509
510        glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
511        endMark();
512    }
513}
514
515void OpenGLRenderer::pushLayerUpdate(Layer* layer) {
516    if (layer) {
517        mLayerUpdates.push_back(layer);
518        mCaches.resourceCache.incrementRefcount(layer);
519    }
520}
521
522void OpenGLRenderer::clearLayerUpdates() {
523    size_t count = mLayerUpdates.size();
524    if (count > 0) {
525        mCaches.resourceCache.lock();
526        for (size_t i = 0; i < count; i++) {
527            mCaches.resourceCache.decrementRefcountLocked(mLayerUpdates.itemAt(i));
528        }
529        mCaches.resourceCache.unlock();
530        mLayerUpdates.clear();
531    }
532}
533
534///////////////////////////////////////////////////////////////////////////////
535// State management
536///////////////////////////////////////////////////////////////////////////////
537
538int OpenGLRenderer::getSaveCount() const {
539    return mSaveCount;
540}
541
542int OpenGLRenderer::save(int flags) {
543    return saveSnapshot(flags);
544}
545
546void OpenGLRenderer::restore() {
547    if (mSaveCount > 1) {
548        restoreSnapshot();
549    }
550}
551
552void OpenGLRenderer::restoreToCount(int saveCount) {
553    if (saveCount < 1) saveCount = 1;
554
555    while (mSaveCount > saveCount) {
556        restoreSnapshot();
557    }
558}
559
560int OpenGLRenderer::saveSnapshot(int flags) {
561    mSnapshot = new Snapshot(mSnapshot, flags);
562    return mSaveCount++;
563}
564
565bool OpenGLRenderer::restoreSnapshot() {
566    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
567    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
568    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
569
570    sp<Snapshot> current = mSnapshot;
571    sp<Snapshot> previous = mSnapshot->previous;
572
573    if (restoreOrtho) {
574        Rect& r = previous->viewport;
575        glViewport(r.left, r.top, r.right, r.bottom);
576        mOrthoMatrix.load(current->orthoMatrix);
577    }
578
579    mSaveCount--;
580    mSnapshot = previous;
581
582    if (restoreClip) {
583        dirtyClip();
584    }
585
586    if (restoreLayer) {
587        composeLayer(current, previous);
588    }
589
590    return restoreClip;
591}
592
593///////////////////////////////////////////////////////////////////////////////
594// Layers
595///////////////////////////////////////////////////////////////////////////////
596
597int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
598        SkPaint* p, int flags) {
599    const GLuint previousFbo = mSnapshot->fbo;
600    const int count = saveSnapshot(flags);
601
602    if (!mSnapshot->isIgnored()) {
603        int alpha = 255;
604        SkXfermode::Mode mode;
605
606        if (p) {
607            alpha = p->getAlpha();
608            mode = getXfermode(p->getXfermode());
609        } else {
610            mode = SkXfermode::kSrcOver_Mode;
611        }
612
613        createLayer(left, top, right, bottom, alpha, mode, flags, previousFbo);
614    }
615
616    return count;
617}
618
619int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
620        int alpha, int flags) {
621    if (alpha >= 255) {
622        return saveLayer(left, top, right, bottom, NULL, flags);
623    } else {
624        SkPaint paint;
625        paint.setAlpha(alpha);
626        return saveLayer(left, top, right, bottom, &paint, flags);
627    }
628}
629
630/**
631 * Layers are viewed by Skia are slightly different than layers in image editing
632 * programs (for instance.) When a layer is created, previously created layers
633 * and the frame buffer still receive every drawing command. For instance, if a
634 * layer is created and a shape intersecting the bounds of the layers and the
635 * framebuffer is draw, the shape will be drawn on both (unless the layer was
636 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
637 *
638 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
639 * texture. Unfortunately, this is inefficient as it requires every primitive to
640 * be drawn n + 1 times, where n is the number of active layers. In practice this
641 * means, for every primitive:
642 *   - Switch active frame buffer
643 *   - Change viewport, clip and projection matrix
644 *   - Issue the drawing
645 *
646 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
647 * To avoid this, layers are implemented in a different way here, at least in the
648 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
649 * is set. When this flag is set we can redirect all drawing operations into a
650 * single FBO.
651 *
652 * This implementation relies on the frame buffer being at least RGBA 8888. When
653 * a layer is created, only a texture is created, not an FBO. The content of the
654 * frame buffer contained within the layer's bounds is copied into this texture
655 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
656 * buffer and drawing continues as normal. This technique therefore treats the
657 * frame buffer as a scratch buffer for the layers.
658 *
659 * To compose the layers back onto the frame buffer, each layer texture
660 * (containing the original frame buffer data) is drawn as a simple quad over
661 * the frame buffer. The trick is that the quad is set as the composition
662 * destination in the blending equation, and the frame buffer becomes the source
663 * of the composition.
664 *
665 * Drawing layers with an alpha value requires an extra step before composition.
666 * An empty quad is drawn over the layer's region in the frame buffer. This quad
667 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
668 * quad is used to multiply the colors in the frame buffer. This is achieved by
669 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
670 * GL_ZERO, GL_SRC_ALPHA.
671 *
672 * Because glCopyTexImage2D() can be slow, an alternative implementation might
673 * be use to draw a single clipped layer. The implementation described above
674 * is correct in every case.
675 *
676 * (1) The frame buffer is actually not cleared right away. To allow the GPU
677 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
678 *     buffer is left untouched until the first drawing operation. Only when
679 *     something actually gets drawn are the layers regions cleared.
680 */
681bool OpenGLRenderer::createLayer(float left, float top, float right, float bottom,
682        int alpha, SkXfermode::Mode mode, int flags, GLuint previousFbo) {
683    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
684    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
685
686    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
687
688    // Window coordinates of the layer
689    Rect clip;
690    Rect bounds(left, top, right, bottom);
691    Rect untransformedBounds(bounds);
692    mSnapshot->transform->mapRect(bounds);
693
694    // Layers only make sense if they are in the framebuffer's bounds
695    if (bounds.intersect(*mSnapshot->clipRect)) {
696        // We cannot work with sub-pixels in this case
697        bounds.snapToPixelBoundaries();
698
699        // When the layer is not an FBO, we may use glCopyTexImage so we
700        // need to make sure the layer does not extend outside the bounds
701        // of the framebuffer
702        if (!bounds.intersect(mSnapshot->previous->viewport)) {
703            bounds.setEmpty();
704        } else if (fboLayer) {
705            clip.set(bounds);
706            mat4 inverse;
707            inverse.loadInverse(*mSnapshot->transform);
708            inverse.mapRect(clip);
709            clip.snapToPixelBoundaries();
710            if (clip.intersect(untransformedBounds)) {
711                clip.translate(-left, -top);
712                bounds.set(untransformedBounds);
713            } else {
714                clip.setEmpty();
715            }
716        }
717    } else {
718        bounds.setEmpty();
719    }
720
721    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
722            bounds.getHeight() > mCaches.maxTextureSize ||
723            (fboLayer && clip.isEmpty())) {
724        mSnapshot->empty = fboLayer;
725    } else {
726        mSnapshot->invisible = mSnapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
727    }
728
729    // Bail out if we won't draw in this snapshot
730    if (mSnapshot->invisible || mSnapshot->empty) {
731        return false;
732    }
733
734    mCaches.activeTexture(0);
735    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
736    if (!layer) {
737        return false;
738    }
739
740    layer->setAlpha(alpha, mode);
741    layer->layer.set(bounds);
742    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
743            bounds.getWidth() / float(layer->getWidth()), 0.0f);
744    layer->setColorFilter(mColorFilter);
745    layer->setBlend(true);
746
747    // Save the layer in the snapshot
748    mSnapshot->flags |= Snapshot::kFlagIsLayer;
749    mSnapshot->layer = layer;
750
751    if (fboLayer) {
752        return createFboLayer(layer, bounds, clip, previousFbo);
753    } else {
754        // Copy the framebuffer into the layer
755        layer->bindTexture();
756        if (!bounds.isEmpty()) {
757            if (layer->isEmpty()) {
758                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
759                        bounds.left, mSnapshot->height - bounds.bottom,
760                        layer->getWidth(), layer->getHeight(), 0);
761                layer->setEmpty(false);
762            } else {
763                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
764                        mSnapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
765            }
766
767            // Enqueue the buffer coordinates to clear the corresponding region later
768            mLayers.push(new Rect(bounds));
769        }
770    }
771
772    return true;
773}
774
775bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, Rect& clip, GLuint previousFbo) {
776    layer->setFbo(mCaches.fboCache.get());
777
778    mSnapshot->region = &mSnapshot->layer->region;
779    mSnapshot->flags |= Snapshot::kFlagFboTarget;
780
781    mSnapshot->flags |= Snapshot::kFlagIsFboLayer;
782    mSnapshot->fbo = layer->getFbo();
783    mSnapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
784    mSnapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
785    mSnapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
786    mSnapshot->height = bounds.getHeight();
787    mSnapshot->flags |= Snapshot::kFlagDirtyOrtho;
788    mSnapshot->orthoMatrix.load(mOrthoMatrix);
789
790    endTiling();
791    debugOverdraw(false, false);
792    // Bind texture to FBO
793    glBindFramebuffer(GL_FRAMEBUFFER, layer->getFbo());
794    layer->bindTexture();
795
796    // Initialize the texture if needed
797    if (layer->isEmpty()) {
798        layer->allocateTexture(GL_RGBA, GL_UNSIGNED_BYTE);
799        layer->setEmpty(false);
800    }
801
802    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
803            layer->getTexture(), 0);
804
805    startTiling(mSnapshot);
806
807    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
808    mCaches.enableScissor();
809    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
810            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
811    glClear(GL_COLOR_BUFFER_BIT);
812
813    dirtyClip();
814
815    // Change the ortho projection
816    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
817    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
818
819    return true;
820}
821
822/**
823 * Read the documentation of createLayer() before doing anything in this method.
824 */
825void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
826    if (!current->layer) {
827        ALOGE("Attempting to compose a layer that does not exist");
828        return;
829    }
830
831    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
832
833    if (fboLayer) {
834        endTiling();
835
836        // Detach the texture from the FBO
837        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
838        // Unbind current FBO and restore previous one
839        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
840        debugOverdraw(true, false);
841
842        startTiling(previous);
843    }
844
845    Layer* layer = current->layer;
846    const Rect& rect = layer->layer;
847
848    if (!fboLayer && layer->getAlpha() < 255) {
849        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
850                layer->getAlpha() << 24, SkXfermode::kDstIn_Mode, true);
851        // Required below, composeLayerRect() will divide by 255
852        layer->setAlpha(255);
853    }
854
855    mCaches.unbindMeshBuffer();
856
857    mCaches.activeTexture(0);
858
859    // When the layer is stored in an FBO, we can save a bit of fillrate by
860    // drawing only the dirty region
861    if (fboLayer) {
862        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
863        if (layer->getColorFilter()) {
864            setupColorFilter(layer->getColorFilter());
865        }
866        composeLayerRegion(layer, rect);
867        if (layer->getColorFilter()) {
868            resetColorFilter();
869        }
870    } else if (!rect.isEmpty()) {
871        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
872        composeLayerRect(layer, rect, true);
873    }
874
875    if (fboLayer) {
876        // Note: No need to use glDiscardFramebufferEXT() since we never
877        //       create/compose layers that are not on screen with this
878        //       code path
879        // See LayerRenderer::destroyLayer(Layer*)
880
881        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
882        mCaches.fboCache.put(current->fbo);
883        layer->setFbo(0);
884    }
885
886    dirtyClip();
887
888    // Failing to add the layer to the cache should happen only if the layer is too large
889    if (!mCaches.layerCache.put(layer)) {
890        LAYER_LOGD("Deleting layer");
891        Caches::getInstance().resourceCache.decrementRefcount(layer);
892    }
893}
894
895void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
896    float alpha = layer->getAlpha() / 255.0f;
897
898    mat4& transform = layer->getTransform();
899    if (!transform.isIdentity()) {
900        save(0);
901        mSnapshot->transform->multiply(transform);
902    }
903
904    setupDraw();
905    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
906        setupDrawWithTexture();
907    } else {
908        setupDrawWithExternalTexture();
909    }
910    setupDrawTextureTransform();
911    setupDrawColor(alpha, alpha, alpha, alpha);
912    setupDrawColorFilter();
913    setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode());
914    setupDrawProgram();
915    setupDrawPureColorUniforms();
916    setupDrawColorFilterUniforms();
917    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
918        setupDrawTexture(layer->getTexture());
919    } else {
920        setupDrawExternalTexture(layer->getTexture());
921    }
922    if (mSnapshot->transform->isPureTranslate() &&
923            layer->getWidth() == (uint32_t) rect.getWidth() &&
924            layer->getHeight() == (uint32_t) rect.getHeight()) {
925        const float x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
926        const float y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
927
928        layer->setFilter(GL_NEAREST);
929        setupDrawModelView(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
930    } else {
931        layer->setFilter(GL_LINEAR);
932        setupDrawModelView(rect.left, rect.top, rect.right, rect.bottom);
933    }
934    setupDrawTextureTransformUniforms(layer->getTexTransform());
935    setupDrawMesh(&mMeshVertices[0].position[0], &mMeshVertices[0].texture[0]);
936
937    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
938
939    finishDrawTexture();
940
941    if (!transform.isIdentity()) {
942        restore();
943    }
944}
945
946void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
947    if (!layer->isTextureLayer()) {
948        const Rect& texCoords = layer->texCoords;
949        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
950                texCoords.right, texCoords.bottom);
951
952        float x = rect.left;
953        float y = rect.top;
954        bool simpleTransform = mSnapshot->transform->isPureTranslate() &&
955                layer->getWidth() == (uint32_t) rect.getWidth() &&
956                layer->getHeight() == (uint32_t) rect.getHeight();
957
958        if (simpleTransform) {
959            // When we're swapping, the layer is already in screen coordinates
960            if (!swap) {
961                x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
962                y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
963            }
964
965            layer->setFilter(GL_NEAREST, true);
966        } else {
967            layer->setFilter(GL_LINEAR, true);
968        }
969
970        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
971                layer->getTexture(), layer->getAlpha() / 255.0f,
972                layer->getMode(), layer->isBlend(),
973                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
974                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
975
976        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
977    } else {
978        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
979        drawTextureLayer(layer, rect);
980        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
981    }
982}
983
984void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
985    if (layer->region.isRect()) {
986        layer->setRegionAsRect();
987
988        composeLayerRect(layer, layer->regionRect);
989
990        layer->region.clear();
991        return;
992    }
993
994    // TODO: See LayerRenderer.cpp::generateMesh() for important
995    //       information about this implementation
996    if (CC_LIKELY(!layer->region.isEmpty())) {
997        size_t count;
998        const android::Rect* rects = layer->region.getArray(&count);
999
1000        const float alpha = layer->getAlpha() / 255.0f;
1001        const float texX = 1.0f / float(layer->getWidth());
1002        const float texY = 1.0f / float(layer->getHeight());
1003        const float height = rect.getHeight();
1004
1005        TextureVertex* mesh = mCaches.getRegionMesh();
1006        GLsizei numQuads = 0;
1007
1008        setupDraw();
1009        setupDrawWithTexture();
1010        setupDrawColor(alpha, alpha, alpha, alpha);
1011        setupDrawColorFilter();
1012        setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode(), false);
1013        setupDrawProgram();
1014        setupDrawDirtyRegionsDisabled();
1015        setupDrawPureColorUniforms();
1016        setupDrawColorFilterUniforms();
1017        setupDrawTexture(layer->getTexture());
1018        if (mSnapshot->transform->isPureTranslate()) {
1019            const float x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
1020            const float y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
1021
1022            layer->setFilter(GL_NEAREST);
1023            setupDrawModelViewTranslate(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
1024        } else {
1025            layer->setFilter(GL_LINEAR);
1026            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1027        }
1028        setupDrawMeshIndices(&mesh[0].position[0], &mesh[0].texture[0]);
1029
1030        for (size_t i = 0; i < count; i++) {
1031            const android::Rect* r = &rects[i];
1032
1033            const float u1 = r->left * texX;
1034            const float v1 = (height - r->top) * texY;
1035            const float u2 = r->right * texX;
1036            const float v2 = (height - r->bottom) * texY;
1037
1038            // TODO: Reject quads outside of the clip
1039            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
1040            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
1041            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
1042            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
1043
1044            numQuads++;
1045
1046            if (numQuads >= REGION_MESH_QUAD_COUNT) {
1047                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
1048                numQuads = 0;
1049                mesh = mCaches.getRegionMesh();
1050            }
1051        }
1052
1053        if (numQuads > 0) {
1054            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
1055        }
1056
1057        finishDrawTexture();
1058
1059#if DEBUG_LAYERS_AS_REGIONS
1060        drawRegionRects(layer->region);
1061#endif
1062
1063        layer->region.clear();
1064    }
1065}
1066
1067void OpenGLRenderer::drawRegionRects(const Region& region) {
1068#if DEBUG_LAYERS_AS_REGIONS
1069    size_t count;
1070    const android::Rect* rects = region.getArray(&count);
1071
1072    uint32_t colors[] = {
1073            0x7fff0000, 0x7f00ff00,
1074            0x7f0000ff, 0x7fff00ff,
1075    };
1076
1077    int offset = 0;
1078    int32_t top = rects[0].top;
1079
1080    for (size_t i = 0; i < count; i++) {
1081        if (top != rects[i].top) {
1082            offset ^= 0x2;
1083            top = rects[i].top;
1084        }
1085
1086        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
1087        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
1088                SkXfermode::kSrcOver_Mode);
1089    }
1090#endif
1091}
1092
1093void OpenGLRenderer::dirtyLayer(const float left, const float top,
1094        const float right, const float bottom, const mat4 transform) {
1095    if (hasLayer()) {
1096        Rect bounds(left, top, right, bottom);
1097        transform.mapRect(bounds);
1098        dirtyLayerUnchecked(bounds, getRegion());
1099    }
1100}
1101
1102void OpenGLRenderer::dirtyLayer(const float left, const float top,
1103        const float right, const float bottom) {
1104    if (hasLayer()) {
1105        Rect bounds(left, top, right, bottom);
1106        dirtyLayerUnchecked(bounds, getRegion());
1107    }
1108}
1109
1110void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
1111    if (bounds.intersect(*mSnapshot->clipRect)) {
1112        bounds.snapToPixelBoundaries();
1113        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1114        if (!dirty.isEmpty()) {
1115            region->orSelf(dirty);
1116        }
1117    }
1118}
1119
1120void OpenGLRenderer::clearLayerRegions() {
1121    const size_t count = mLayers.size();
1122    if (count == 0) return;
1123
1124    if (!mSnapshot->isIgnored()) {
1125        // Doing several glScissor/glClear here can negatively impact
1126        // GPUs with a tiler architecture, instead we draw quads with
1127        // the Clear blending mode
1128
1129        // The list contains bounds that have already been clipped
1130        // against their initial clip rect, and the current clip
1131        // is likely different so we need to disable clipping here
1132        bool scissorChanged = mCaches.disableScissor();
1133
1134        Vertex mesh[count * 6];
1135        Vertex* vertex = mesh;
1136
1137        for (uint32_t i = 0; i < count; i++) {
1138            Rect* bounds = mLayers.itemAt(i);
1139
1140            Vertex::set(vertex++, bounds->left, bounds->bottom);
1141            Vertex::set(vertex++, bounds->left, bounds->top);
1142            Vertex::set(vertex++, bounds->right, bounds->top);
1143            Vertex::set(vertex++, bounds->left, bounds->bottom);
1144            Vertex::set(vertex++, bounds->right, bounds->top);
1145            Vertex::set(vertex++, bounds->right, bounds->bottom);
1146
1147            delete bounds;
1148        }
1149
1150        setupDraw(false);
1151        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
1152        setupDrawBlending(true, SkXfermode::kClear_Mode);
1153        setupDrawProgram();
1154        setupDrawPureColorUniforms();
1155        setupDrawModelViewTranslate(0.0f, 0.0f, 0.0f, 0.0f, true);
1156        setupDrawVertices(&mesh[0].position[0]);
1157
1158        glDrawArrays(GL_TRIANGLES, 0, count * 6);
1159
1160        if (scissorChanged) mCaches.enableScissor();
1161    } else {
1162        for (uint32_t i = 0; i < count; i++) {
1163            delete mLayers.itemAt(i);
1164        }
1165    }
1166
1167    mLayers.clear();
1168}
1169
1170///////////////////////////////////////////////////////////////////////////////
1171// Transforms
1172///////////////////////////////////////////////////////////////////////////////
1173
1174void OpenGLRenderer::translate(float dx, float dy) {
1175    mSnapshot->transform->translate(dx, dy, 0.0f);
1176}
1177
1178void OpenGLRenderer::rotate(float degrees) {
1179    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
1180}
1181
1182void OpenGLRenderer::scale(float sx, float sy) {
1183    mSnapshot->transform->scale(sx, sy, 1.0f);
1184}
1185
1186void OpenGLRenderer::skew(float sx, float sy) {
1187    mSnapshot->transform->skew(sx, sy);
1188}
1189
1190void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
1191    if (matrix) {
1192        mSnapshot->transform->load(*matrix);
1193    } else {
1194        mSnapshot->transform->loadIdentity();
1195    }
1196}
1197
1198void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
1199    mSnapshot->transform->copyTo(*matrix);
1200}
1201
1202void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
1203    SkMatrix transform;
1204    mSnapshot->transform->copyTo(transform);
1205    transform.preConcat(*matrix);
1206    mSnapshot->transform->load(transform);
1207}
1208
1209///////////////////////////////////////////////////////////////////////////////
1210// Clipping
1211///////////////////////////////////////////////////////////////////////////////
1212
1213void OpenGLRenderer::setScissorFromClip() {
1214    Rect clip(*mSnapshot->clipRect);
1215    clip.snapToPixelBoundaries();
1216
1217    if (mCaches.setScissor(clip.left, mSnapshot->height - clip.bottom,
1218            clip.getWidth(), clip.getHeight())) {
1219        mDirtyClip = false;
1220    }
1221}
1222
1223const Rect& OpenGLRenderer::getClipBounds() {
1224    return mSnapshot->getLocalClip();
1225}
1226
1227bool OpenGLRenderer::quickRejectNoScissor(float left, float top, float right, float bottom) {
1228    if (mSnapshot->isIgnored()) {
1229        return true;
1230    }
1231
1232    Rect r(left, top, right, bottom);
1233    mSnapshot->transform->mapRect(r);
1234    r.snapToPixelBoundaries();
1235
1236    Rect clipRect(*mSnapshot->clipRect);
1237    clipRect.snapToPixelBoundaries();
1238
1239    return !clipRect.intersects(r);
1240}
1241
1242bool OpenGLRenderer::quickRejectNoScissor(float left, float top, float right, float bottom,
1243        Rect& transformed, Rect& clip) {
1244    if (mSnapshot->isIgnored()) {
1245        return true;
1246    }
1247
1248    transformed.set(left, top, right, bottom);
1249    mSnapshot->transform->mapRect(transformed);
1250    transformed.snapToPixelBoundaries();
1251
1252    clip.set(*mSnapshot->clipRect);
1253    clip.snapToPixelBoundaries();
1254
1255    return !clip.intersects(transformed);
1256}
1257
1258bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
1259    if (mSnapshot->isIgnored()) {
1260        return true;
1261    }
1262
1263    Rect r(left, top, right, bottom);
1264    mSnapshot->transform->mapRect(r);
1265    r.snapToPixelBoundaries();
1266
1267    Rect clipRect(*mSnapshot->clipRect);
1268    clipRect.snapToPixelBoundaries();
1269
1270    bool rejected = !clipRect.intersects(r);
1271    if (!isDeferred() && !rejected) {
1272        mCaches.setScissorEnabled(mScissorOptimizationDisabled || !clipRect.contains(r));
1273    }
1274
1275    return rejected;
1276}
1277
1278bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
1279    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
1280    if (clipped) {
1281        dirtyClip();
1282    }
1283    return !mSnapshot->clipRect->isEmpty();
1284}
1285
1286Rect* OpenGLRenderer::getClipRect() {
1287    return mSnapshot->clipRect;
1288}
1289
1290///////////////////////////////////////////////////////////////////////////////
1291// Drawing commands
1292///////////////////////////////////////////////////////////////////////////////
1293
1294void OpenGLRenderer::setupDraw(bool clear) {
1295    // TODO: It would be best if we could do this before quickReject()
1296    //       changes the scissor test state
1297    if (clear) clearLayerRegions();
1298    if (mDirtyClip) {
1299        setScissorFromClip();
1300    }
1301    mDescription.reset();
1302    mSetShaderColor = false;
1303    mColorSet = false;
1304    mColorA = mColorR = mColorG = mColorB = 0.0f;
1305    mTextureUnit = 0;
1306    mTrackDirtyRegions = true;
1307}
1308
1309void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1310    mDescription.hasTexture = true;
1311    mDescription.hasAlpha8Texture = isAlpha8;
1312}
1313
1314void OpenGLRenderer::setupDrawWithExternalTexture() {
1315    mDescription.hasExternalTexture = true;
1316}
1317
1318void OpenGLRenderer::setupDrawNoTexture() {
1319    mCaches.disbaleTexCoordsVertexArray();
1320}
1321
1322void OpenGLRenderer::setupDrawAA() {
1323    mDescription.isAA = true;
1324}
1325
1326void OpenGLRenderer::setupDrawVertexShape() {
1327    mDescription.isVertexShape = true;
1328}
1329
1330void OpenGLRenderer::setupDrawPoint(float pointSize) {
1331    mDescription.isPoint = true;
1332    mDescription.pointSize = pointSize;
1333}
1334
1335void OpenGLRenderer::setupDrawColor(int color) {
1336    setupDrawColor(color, (color >> 24) & 0xFF);
1337}
1338
1339void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1340    mColorA = alpha / 255.0f;
1341    // Second divide of a by 255 is an optimization, allowing us to simply multiply
1342    // the rgb values by a instead of also dividing by 255
1343    const float a = mColorA / 255.0f;
1344    mColorR = a * ((color >> 16) & 0xFF);
1345    mColorG = a * ((color >>  8) & 0xFF);
1346    mColorB = a * ((color      ) & 0xFF);
1347    mColorSet = true;
1348    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
1349}
1350
1351void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1352    mColorA = alpha / 255.0f;
1353    // Double-divide of a by 255 is an optimization, allowing us to simply multiply
1354    // the rgb values by a instead of also dividing by 255
1355    const float a = mColorA / 255.0f;
1356    mColorR = a * ((color >> 16) & 0xFF);
1357    mColorG = a * ((color >>  8) & 0xFF);
1358    mColorB = a * ((color      ) & 0xFF);
1359    mColorSet = true;
1360    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
1361}
1362
1363void OpenGLRenderer::setupDrawTextGamma(const SkPaint* paint) {
1364    mCaches.fontRenderer->describe(mDescription, paint);
1365}
1366
1367void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1368    mColorA = a;
1369    mColorR = r;
1370    mColorG = g;
1371    mColorB = b;
1372    mColorSet = true;
1373    mSetShaderColor = mDescription.setColor(r, g, b, a);
1374}
1375
1376void OpenGLRenderer::setupDrawShader() {
1377    if (mShader) {
1378        mShader->describe(mDescription, mCaches.extensions);
1379    }
1380}
1381
1382void OpenGLRenderer::setupDrawColorFilter() {
1383    if (mColorFilter) {
1384        mColorFilter->describe(mDescription, mCaches.extensions);
1385    }
1386}
1387
1388void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1389    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1390        mColorA = 1.0f;
1391        mColorR = mColorG = mColorB = 0.0f;
1392        mSetShaderColor = mDescription.modulate = true;
1393    }
1394}
1395
1396void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
1397    // When the blending mode is kClear_Mode, we need to use a modulate color
1398    // argb=1,0,0,0
1399    accountForClear(mode);
1400    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
1401            mDescription, swapSrcDst);
1402}
1403
1404void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
1405    // When the blending mode is kClear_Mode, we need to use a modulate color
1406    // argb=1,0,0,0
1407    accountForClear(mode);
1408    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()) ||
1409            (mColorFilter && mColorFilter->blend()), mode, mDescription, swapSrcDst);
1410}
1411
1412void OpenGLRenderer::setupDrawProgram() {
1413    useProgram(mCaches.programCache.get(mDescription));
1414}
1415
1416void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1417    mTrackDirtyRegions = false;
1418}
1419
1420void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
1421        bool ignoreTransform) {
1422    mModelView.loadTranslate(left, top, 0.0f);
1423    if (!ignoreTransform) {
1424        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
1425        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1426    } else {
1427        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
1428        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
1429    }
1430}
1431
1432void OpenGLRenderer::setupDrawModelViewIdentity(bool offset) {
1433    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform, offset);
1434}
1435
1436void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
1437        bool ignoreTransform, bool ignoreModelView) {
1438    if (!ignoreModelView) {
1439        mModelView.loadTranslate(left, top, 0.0f);
1440        mModelView.scale(right - left, bottom - top, 1.0f);
1441    } else {
1442        mModelView.loadIdentity();
1443    }
1444    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1445    if (!ignoreTransform) {
1446        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
1447        if (mTrackDirtyRegions && dirty) {
1448            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1449        }
1450    } else {
1451        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
1452        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
1453    }
1454}
1455
1456void OpenGLRenderer::setupDrawPointUniforms() {
1457    int slot = mCaches.currentProgram->getUniform("pointSize");
1458    glUniform1f(slot, mDescription.pointSize);
1459}
1460
1461void OpenGLRenderer::setupDrawColorUniforms() {
1462    if ((mColorSet && !mShader) || (mShader && mSetShaderColor)) {
1463        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1464    }
1465}
1466
1467void OpenGLRenderer::setupDrawPureColorUniforms() {
1468    if (mSetShaderColor) {
1469        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1470    }
1471}
1472
1473void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1474    if (mShader) {
1475        if (ignoreTransform) {
1476            mModelView.loadInverse(*mSnapshot->transform);
1477        }
1478        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
1479    }
1480}
1481
1482void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1483    if (mShader) {
1484        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1485    }
1486}
1487
1488void OpenGLRenderer::setupDrawColorFilterUniforms() {
1489    if (mColorFilter) {
1490        mColorFilter->setupProgram(mCaches.currentProgram);
1491    }
1492}
1493
1494void OpenGLRenderer::setupDrawTextGammaUniforms() {
1495    mCaches.fontRenderer->setupProgram(mDescription, mCaches.currentProgram);
1496}
1497
1498void OpenGLRenderer::setupDrawSimpleMesh() {
1499    bool force = mCaches.bindMeshBuffer();
1500    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, 0);
1501    mCaches.unbindIndicesBuffer();
1502}
1503
1504void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1505    bindTexture(texture);
1506    mTextureUnit++;
1507    mCaches.enableTexCoordsVertexArray();
1508}
1509
1510void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1511    bindExternalTexture(texture);
1512    mTextureUnit++;
1513    mCaches.enableTexCoordsVertexArray();
1514}
1515
1516void OpenGLRenderer::setupDrawTextureTransform() {
1517    mDescription.hasTextureTransform = true;
1518}
1519
1520void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1521    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1522            GL_FALSE, &transform.data[0]);
1523}
1524
1525void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1526    bool force = false;
1527    if (!vertices) {
1528        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1529    } else {
1530        force = mCaches.unbindMeshBuffer();
1531    }
1532
1533    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, vertices);
1534    if (mCaches.currentProgram->texCoords >= 0) {
1535        mCaches.bindTexCoordsVertexPointer(force, mCaches.currentProgram->texCoords, texCoords);
1536    }
1537
1538    mCaches.unbindIndicesBuffer();
1539}
1540
1541void OpenGLRenderer::setupDrawMeshIndices(GLvoid* vertices, GLvoid* texCoords) {
1542    bool force = mCaches.unbindMeshBuffer();
1543    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, vertices);
1544    if (mCaches.currentProgram->texCoords >= 0) {
1545        mCaches.bindTexCoordsVertexPointer(force, mCaches.currentProgram->texCoords, texCoords);
1546    }
1547}
1548
1549void OpenGLRenderer::setupDrawVertices(GLvoid* vertices) {
1550    bool force = mCaches.unbindMeshBuffer();
1551    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position,
1552            vertices, gVertexStride);
1553    mCaches.unbindIndicesBuffer();
1554}
1555
1556/**
1557 * Sets up the shader to draw an AA line. We draw AA lines with quads, where there is an
1558 * outer boundary that fades out to 0. The variables set in the shader define the proportion of
1559 * the width and length of the primitive occupied by the AA region. The vtxWidth and vtxLength
1560 * attributes (one per vertex) are values from zero to one that tells the fragment
1561 * shader where the fragment is in relation to the line width/length overall; these values are
1562 * then used to compute the proper color, based on whether the fragment lies in the fading AA
1563 * region of the line.
1564 * Note that we only pass down the width values in this setup function. The length coordinates
1565 * are set up for each individual segment.
1566 */
1567void OpenGLRenderer::setupDrawAALine(GLvoid* vertices, GLvoid* widthCoords,
1568        GLvoid* lengthCoords, float boundaryWidthProportion, int& widthSlot, int& lengthSlot) {
1569    bool force = mCaches.unbindMeshBuffer();
1570    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position,
1571            vertices, gAAVertexStride);
1572    mCaches.resetTexCoordsVertexPointer();
1573    mCaches.unbindIndicesBuffer();
1574
1575    widthSlot = mCaches.currentProgram->getAttrib("vtxWidth");
1576    glEnableVertexAttribArray(widthSlot);
1577    glVertexAttribPointer(widthSlot, 1, GL_FLOAT, GL_FALSE, gAAVertexStride, widthCoords);
1578
1579    lengthSlot = mCaches.currentProgram->getAttrib("vtxLength");
1580    glEnableVertexAttribArray(lengthSlot);
1581    glVertexAttribPointer(lengthSlot, 1, GL_FLOAT, GL_FALSE, gAAVertexStride, lengthCoords);
1582
1583    int boundaryWidthSlot = mCaches.currentProgram->getUniform("boundaryWidth");
1584    glUniform1f(boundaryWidthSlot, boundaryWidthProportion);
1585}
1586
1587void OpenGLRenderer::finishDrawAALine(const int widthSlot, const int lengthSlot) {
1588    glDisableVertexAttribArray(widthSlot);
1589    glDisableVertexAttribArray(lengthSlot);
1590}
1591
1592void OpenGLRenderer::finishDrawTexture() {
1593}
1594
1595///////////////////////////////////////////////////////////////////////////////
1596// Drawing
1597///////////////////////////////////////////////////////////////////////////////
1598
1599status_t OpenGLRenderer::drawDisplayList(DisplayList* displayList,
1600        Rect& dirty, int32_t flags, uint32_t level) {
1601
1602    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1603    // will be performed by the display list itself
1604    if (displayList && displayList->isRenderable()) {
1605        return displayList->replay(*this, dirty, flags, level);
1606    }
1607
1608    return DrawGlInfo::kStatusDone;
1609}
1610
1611void OpenGLRenderer::outputDisplayList(DisplayList* displayList, uint32_t level) {
1612    if (displayList) {
1613        displayList->output(*this, level);
1614    }
1615}
1616
1617void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, SkPaint* paint) {
1618    int alpha;
1619    SkXfermode::Mode mode;
1620    getAlphaAndMode(paint, &alpha, &mode);
1621
1622    float x = left;
1623    float y = top;
1624
1625    GLenum filter = GL_LINEAR;
1626    bool ignoreTransform = false;
1627    if (mSnapshot->transform->isPureTranslate()) {
1628        x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1629        y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1630        ignoreTransform = true;
1631        filter = GL_NEAREST;
1632    } else {
1633        filter = FILTER(paint);
1634    }
1635
1636    setupDraw();
1637    setupDrawWithTexture(true);
1638    if (paint) {
1639        setupDrawAlpha8Color(paint->getColor(), alpha);
1640    }
1641    setupDrawColorFilter();
1642    setupDrawShader();
1643    setupDrawBlending(true, mode);
1644    setupDrawProgram();
1645    setupDrawModelView(x, y, x + texture->width, y + texture->height, ignoreTransform);
1646
1647    setupDrawTexture(texture->id);
1648    texture->setWrap(GL_CLAMP_TO_EDGE);
1649    texture->setFilter(filter);
1650
1651    setupDrawPureColorUniforms();
1652    setupDrawColorFilterUniforms();
1653    setupDrawShaderUniforms();
1654    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1655
1656    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1657
1658    finishDrawTexture();
1659}
1660
1661status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1662    const float right = left + bitmap->width();
1663    const float bottom = top + bitmap->height();
1664
1665    if (quickReject(left, top, right, bottom)) {
1666        return DrawGlInfo::kStatusDone;
1667    }
1668
1669    mCaches.activeTexture(0);
1670    Texture* texture = mCaches.textureCache.get(bitmap);
1671    if (!texture) return DrawGlInfo::kStatusDone;
1672    const AutoTexture autoCleanup(texture);
1673
1674    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
1675        drawAlphaBitmap(texture, left, top, paint);
1676    } else {
1677        drawTextureRect(left, top, right, bottom, texture, paint);
1678    }
1679
1680    return DrawGlInfo::kStatusDrew;
1681}
1682
1683status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1684    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1685    const mat4 transform(*matrix);
1686    transform.mapRect(r);
1687
1688    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1689        return DrawGlInfo::kStatusDone;
1690    }
1691
1692    mCaches.activeTexture(0);
1693    Texture* texture = mCaches.textureCache.get(bitmap);
1694    if (!texture) return DrawGlInfo::kStatusDone;
1695    const AutoTexture autoCleanup(texture);
1696
1697    // This could be done in a cheaper way, all we need is pass the matrix
1698    // to the vertex shader. The save/restore is a bit overkill.
1699    save(SkCanvas::kMatrix_SaveFlag);
1700    concatMatrix(matrix);
1701    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1702    restore();
1703
1704    return DrawGlInfo::kStatusDrew;
1705}
1706
1707status_t OpenGLRenderer::drawBitmapData(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1708    const float right = left + bitmap->width();
1709    const float bottom = top + bitmap->height();
1710
1711    if (quickReject(left, top, right, bottom)) {
1712        return DrawGlInfo::kStatusDone;
1713    }
1714
1715    mCaches.activeTexture(0);
1716    Texture* texture = mCaches.textureCache.getTransient(bitmap);
1717    const AutoTexture autoCleanup(texture);
1718
1719    drawTextureRect(left, top, right, bottom, texture, paint);
1720
1721    return DrawGlInfo::kStatusDrew;
1722}
1723
1724status_t OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1725        float* vertices, int* colors, SkPaint* paint) {
1726    // TODO: Do a quickReject
1727    if (!vertices || mSnapshot->isIgnored()) {
1728        return DrawGlInfo::kStatusDone;
1729    }
1730
1731    mCaches.activeTexture(0);
1732    Texture* texture = mCaches.textureCache.get(bitmap);
1733    if (!texture) return DrawGlInfo::kStatusDone;
1734    const AutoTexture autoCleanup(texture);
1735
1736    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1737    texture->setFilter(FILTER(paint), true);
1738
1739    int alpha;
1740    SkXfermode::Mode mode;
1741    getAlphaAndMode(paint, &alpha, &mode);
1742
1743    const uint32_t count = meshWidth * meshHeight * 6;
1744
1745    float left = FLT_MAX;
1746    float top = FLT_MAX;
1747    float right = FLT_MIN;
1748    float bottom = FLT_MIN;
1749
1750    const bool hasActiveLayer = hasLayer();
1751
1752    // TODO: Support the colors array
1753    TextureVertex mesh[count];
1754    TextureVertex* vertex = mesh;
1755    for (int32_t y = 0; y < meshHeight; y++) {
1756        for (int32_t x = 0; x < meshWidth; x++) {
1757            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1758
1759            float u1 = float(x) / meshWidth;
1760            float u2 = float(x + 1) / meshWidth;
1761            float v1 = float(y) / meshHeight;
1762            float v2 = float(y + 1) / meshHeight;
1763
1764            int ax = i + (meshWidth + 1) * 2;
1765            int ay = ax + 1;
1766            int bx = i;
1767            int by = bx + 1;
1768            int cx = i + 2;
1769            int cy = cx + 1;
1770            int dx = i + (meshWidth + 1) * 2 + 2;
1771            int dy = dx + 1;
1772
1773            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1774            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1775            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1776
1777            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1778            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1779            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1780
1781            if (hasActiveLayer) {
1782                // TODO: This could be optimized to avoid unnecessary ops
1783                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1784                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1785                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1786                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1787            }
1788        }
1789    }
1790
1791    if (hasActiveLayer) {
1792        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1793    }
1794
1795    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1796            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1797            GL_TRIANGLES, count, false, false, 0, false, false);
1798
1799    return DrawGlInfo::kStatusDrew;
1800}
1801
1802status_t OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1803         float srcLeft, float srcTop, float srcRight, float srcBottom,
1804         float dstLeft, float dstTop, float dstRight, float dstBottom,
1805         SkPaint* paint) {
1806    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1807        return DrawGlInfo::kStatusDone;
1808    }
1809
1810    mCaches.activeTexture(0);
1811    Texture* texture = mCaches.textureCache.get(bitmap);
1812    if (!texture) return DrawGlInfo::kStatusDone;
1813    const AutoTexture autoCleanup(texture);
1814
1815    const float width = texture->width;
1816    const float height = texture->height;
1817
1818    const float u1 = fmax(0.0f, srcLeft / width);
1819    const float v1 = fmax(0.0f, srcTop / height);
1820    const float u2 = fmin(1.0f, srcRight / width);
1821    const float v2 = fmin(1.0f, srcBottom / height);
1822
1823    mCaches.unbindMeshBuffer();
1824    resetDrawTextureTexCoords(u1, v1, u2, v2);
1825
1826    int alpha;
1827    SkXfermode::Mode mode;
1828    getAlphaAndMode(paint, &alpha, &mode);
1829
1830    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1831
1832    if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
1833        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1834        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1835
1836        GLenum filter = GL_NEAREST;
1837        // Enable linear filtering if the source rectangle is scaled
1838        if (srcRight - srcLeft != dstRight - dstLeft || srcBottom - srcTop != dstBottom - dstTop) {
1839            filter = FILTER(paint);
1840        }
1841
1842        texture->setFilter(filter, true);
1843        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1844                texture->id, alpha / 255.0f, mode, texture->blend,
1845                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1846                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1847    } else {
1848        texture->setFilter(FILTER(paint), true);
1849        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1850                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1851                GL_TRIANGLE_STRIP, gMeshCount);
1852    }
1853
1854    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1855
1856    return DrawGlInfo::kStatusDrew;
1857}
1858
1859status_t OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1860        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1861        float left, float top, float right, float bottom, SkPaint* paint) {
1862    int alpha;
1863    SkXfermode::Mode mode;
1864    getAlphaAndModeDirect(paint, &alpha, &mode);
1865
1866    return drawPatch(bitmap, xDivs, yDivs, colors, width, height, numColors,
1867            left, top, right, bottom, alpha, mode);
1868}
1869
1870status_t OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1871        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1872        float left, float top, float right, float bottom, int alpha, SkXfermode::Mode mode) {
1873    if (quickReject(left, top, right, bottom)) {
1874        return DrawGlInfo::kStatusDone;
1875    }
1876
1877    alpha *= mSnapshot->alpha;
1878
1879    mCaches.activeTexture(0);
1880    Texture* texture = mCaches.textureCache.get(bitmap);
1881    if (!texture) return DrawGlInfo::kStatusDone;
1882    const AutoTexture autoCleanup(texture);
1883    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1884    texture->setFilter(GL_LINEAR, true);
1885
1886    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1887            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1888
1889    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
1890        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1891        // Mark the current layer dirty where we are going to draw the patch
1892        if (hasLayer() && mesh->hasEmptyQuads) {
1893            const float offsetX = left + mSnapshot->transform->getTranslateX();
1894            const float offsetY = top + mSnapshot->transform->getTranslateY();
1895            const size_t count = mesh->quads.size();
1896            for (size_t i = 0; i < count; i++) {
1897                const Rect& bounds = mesh->quads.itemAt(i);
1898                if (CC_LIKELY(pureTranslate)) {
1899                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1900                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1901                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1902                } else {
1903                    dirtyLayer(left + bounds.left, top + bounds.top,
1904                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1905                }
1906            }
1907        }
1908
1909        if (CC_LIKELY(pureTranslate)) {
1910            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1911            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1912
1913            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1914                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1915                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1916                    true, !mesh->hasEmptyQuads);
1917        } else {
1918            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1919                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1920                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1921                    true, !mesh->hasEmptyQuads);
1922        }
1923    }
1924
1925    return DrawGlInfo::kStatusDrew;
1926}
1927
1928/**
1929 * This function uses a similar approach to that of AA lines in the drawLines() function.
1930 * We expand the rectangle by a half pixel in screen space on all sides. However, instead of using
1931 * a fragment shader to compute the translucency of the color from its position, we simply use a
1932 * varying parameter to define how far a given pixel is into the region.
1933 */
1934void OpenGLRenderer::drawConvexPath(const SkPath& path, int color, SkXfermode::Mode mode, bool isAA) {
1935    VertexBuffer vertexBuffer;
1936    // TODO: try clipping large paths to viewport
1937    PathRenderer::convexPathFillVertices(path, mSnapshot->transform, vertexBuffer, isAA);
1938
1939    setupDraw();
1940    setupDrawNoTexture();
1941    if (isAA) setupDrawAA();
1942    setupDrawVertexShape();
1943    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
1944    setupDrawColorFilter();
1945    setupDrawShader();
1946    setupDrawBlending(isAA, mode);
1947    setupDrawProgram();
1948    setupDrawModelViewIdentity(true);
1949    setupDrawColorUniforms();
1950    setupDrawColorFilterUniforms();
1951    setupDrawShaderIdentityUniforms();
1952
1953    void* vertices = vertexBuffer.getBuffer();
1954    bool force = mCaches.unbindMeshBuffer();
1955    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position,
1956                                      vertices, isAA ? gAlphaVertexStride : gVertexStride);
1957    mCaches.resetTexCoordsVertexPointer();
1958    mCaches.unbindIndicesBuffer();
1959
1960    int alphaSlot = -1;
1961    if (isAA) {
1962        void* alphaCoords = ((GLbyte*) vertices) + gVertexAlphaOffset;
1963        alphaSlot = mCaches.currentProgram->getAttrib("vtxAlpha");
1964
1965        // TODO: avoid enable/disable in back to back uses of the alpha attribute
1966        glEnableVertexAttribArray(alphaSlot);
1967        glVertexAttribPointer(alphaSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, alphaCoords);
1968    }
1969
1970    SkRect bounds = path.getBounds();
1971    dirtyLayer(bounds.fLeft, bounds.fTop, bounds.fRight, bounds.fBottom, *mSnapshot->transform);
1972
1973    glDrawArrays(GL_TRIANGLE_STRIP, 0, vertexBuffer.getSize());
1974
1975    if (isAA) {
1976        glDisableVertexAttribArray(alphaSlot);
1977    }
1978}
1979
1980/**
1981 * We draw lines as quads (tristrips). Using GL_LINES can be difficult because the rasterization
1982 * rules for those lines produces some unexpected results, and may vary between hardware devices.
1983 * The basics of lines-as-quads is easy; we simply find the normal to the line and position the
1984 * corners of the quads on either side of each line endpoint, separated by the strokeWidth
1985 * of the line. Hairlines are more involved because we need to account for transform scaling
1986 * to end up with a one-pixel-wide line in screen space..
1987 * Anti-aliased lines add another factor to the approach. We use a specialized fragment shader
1988 * in combination with values that we calculate and pass down in this method. The basic approach
1989 * is that the quad we create contains both the core line area plus a bounding area in which
1990 * the translucent/AA pixels are drawn. The values we calculate tell the shader what
1991 * proportion of the width and the length of a given segment is represented by the boundary
1992 * region. The quad ends up being exactly .5 pixel larger in all directions than the non-AA quad.
1993 * The bounding region is actually 1 pixel wide on all sides (half pixel on the outside, half pixel
1994 * on the inside). This ends up giving the result we want, with pixels that are completely
1995 * 'inside' the line area being filled opaquely and the other pixels being filled according to
1996 * how far into the boundary region they are, which is determined by shader interpolation.
1997 */
1998status_t OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1999    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2000
2001    const bool isAA = paint->isAntiAlias();
2002    // We use half the stroke width here because we're going to position the quad
2003    // corner vertices half of the width away from the line endpoints
2004    float halfStrokeWidth = paint->getStrokeWidth() * 0.5f;
2005    // A stroke width of 0 has a special meaning in Skia:
2006    // it draws a line 1 px wide regardless of current transform
2007    bool isHairLine = paint->getStrokeWidth() == 0.0f;
2008
2009    float inverseScaleX = 1.0f;
2010    float inverseScaleY = 1.0f;
2011    bool scaled = false;
2012
2013    int alpha;
2014    SkXfermode::Mode mode;
2015
2016    int generatedVerticesCount = 0;
2017    int verticesCount = count;
2018    if (count > 4) {
2019        // Polyline: account for extra vertices needed for continuous tri-strip
2020        verticesCount += (count - 4);
2021    }
2022
2023    if (isHairLine || isAA) {
2024        // The quad that we use for AA and hairlines needs to account for scaling. For hairlines
2025        // the line on the screen should always be one pixel wide regardless of scale. For
2026        // AA lines, we only want one pixel of translucent boundary around the quad.
2027        if (CC_UNLIKELY(!mSnapshot->transform->isPureTranslate())) {
2028            Matrix4 *mat = mSnapshot->transform;
2029            float m00 = mat->data[Matrix4::kScaleX];
2030            float m01 = mat->data[Matrix4::kSkewY];
2031            float m10 = mat->data[Matrix4::kSkewX];
2032            float m11 = mat->data[Matrix4::kScaleY];
2033
2034            float scaleX = sqrtf(m00 * m00 + m01 * m01);
2035            float scaleY = sqrtf(m10 * m10 + m11 * m11);
2036
2037            inverseScaleX = (scaleX != 0) ? (inverseScaleX / scaleX) : 0;
2038            inverseScaleY = (scaleY != 0) ? (inverseScaleY / scaleY) : 0;
2039
2040            if (inverseScaleX != 1.0f || inverseScaleY != 1.0f) {
2041                scaled = true;
2042            }
2043        }
2044    }
2045
2046    getAlphaAndMode(paint, &alpha, &mode);
2047
2048    mCaches.enableScissor();
2049
2050    setupDraw();
2051    setupDrawNoTexture();
2052    if (isAA) {
2053        setupDrawAA();
2054    }
2055    setupDrawColor(paint->getColor(), alpha);
2056    setupDrawColorFilter();
2057    setupDrawShader();
2058    setupDrawBlending(isAA, mode);
2059    setupDrawProgram();
2060    setupDrawModelViewIdentity(true);
2061    setupDrawColorUniforms();
2062    setupDrawColorFilterUniforms();
2063    setupDrawShaderIdentityUniforms();
2064
2065    if (isHairLine) {
2066        // Set a real stroke width to be used in quad construction
2067        halfStrokeWidth = isAA? 1 : .5;
2068    } else if (isAA && !scaled) {
2069        // Expand boundary to enable AA calculations on the quad border
2070        halfStrokeWidth += .5f;
2071    }
2072
2073    int widthSlot;
2074    int lengthSlot;
2075
2076    Vertex lines[verticesCount];
2077    Vertex* vertices = &lines[0];
2078
2079    AAVertex wLines[verticesCount];
2080    AAVertex* aaVertices = &wLines[0];
2081
2082    if (CC_UNLIKELY(!isAA)) {
2083        setupDrawVertices(vertices);
2084    } else {
2085        void* widthCoords = ((GLbyte*) aaVertices) + gVertexAAWidthOffset;
2086        void* lengthCoords = ((GLbyte*) aaVertices) + gVertexAALengthOffset;
2087        // innerProportion is the ratio of the inner (non-AA) part of the line to the total
2088        // AA stroke width (the base stroke width expanded by a half pixel on either side).
2089        // This value is used in the fragment shader to determine how to fill fragments.
2090        // We will need to calculate the actual width proportion on each segment for
2091        // scaled non-hairlines, since the boundary proportion may differ per-axis when scaled.
2092        float boundaryWidthProportion = .5 - 1 / (2 * halfStrokeWidth);
2093        setupDrawAALine((void*) aaVertices, widthCoords, lengthCoords,
2094                boundaryWidthProportion, widthSlot, lengthSlot);
2095    }
2096
2097    AAVertex* prevAAVertex = NULL;
2098    Vertex* prevVertex = NULL;
2099
2100    int boundaryLengthSlot = -1;
2101    int boundaryWidthSlot = -1;
2102
2103    for (int i = 0; i < count; i += 4) {
2104        // a = start point, b = end point
2105        vec2 a(points[i], points[i + 1]);
2106        vec2 b(points[i + 2], points[i + 3]);
2107
2108        float length = 0;
2109        float boundaryLengthProportion = 0;
2110        float boundaryWidthProportion = 0;
2111
2112        // Find the normal to the line
2113        vec2 n = (b - a).copyNormalized() * halfStrokeWidth;
2114        float x = n.x;
2115        n.x = -n.y;
2116        n.y = x;
2117
2118        if (isHairLine) {
2119            if (isAA) {
2120                float wideningFactor;
2121                if (fabs(n.x) >= fabs(n.y)) {
2122                    wideningFactor = fabs(1.0f / n.x);
2123                } else {
2124                    wideningFactor = fabs(1.0f / n.y);
2125                }
2126                n *= wideningFactor;
2127            }
2128
2129            if (scaled) {
2130                n.x *= inverseScaleX;
2131                n.y *= inverseScaleY;
2132            }
2133        } else if (scaled) {
2134            // Extend n by .5 pixel on each side, post-transform
2135            vec2 extendedN = n.copyNormalized();
2136            extendedN /= 2;
2137            extendedN.x *= inverseScaleX;
2138            extendedN.y *= inverseScaleY;
2139
2140            float extendedNLength = extendedN.length();
2141            // We need to set this value on the shader prior to drawing
2142            boundaryWidthProportion = .5 - extendedNLength / (halfStrokeWidth + extendedNLength);
2143            n += extendedN;
2144        }
2145
2146        // aa lines expand the endpoint vertices to encompass the AA boundary
2147        if (isAA) {
2148            vec2 abVector = (b - a);
2149            length = abVector.length();
2150            abVector.normalize();
2151
2152            if (scaled) {
2153                abVector.x *= inverseScaleX;
2154                abVector.y *= inverseScaleY;
2155                float abLength = abVector.length();
2156                boundaryLengthProportion = .5 - abLength / (length + abLength);
2157            } else {
2158                boundaryLengthProportion = .5 - .5 / (length + 1);
2159            }
2160
2161            abVector /= 2;
2162            a -= abVector;
2163            b += abVector;
2164        }
2165
2166        // Four corners of the rectangle defining a thick line
2167        vec2 p1 = a - n;
2168        vec2 p2 = a + n;
2169        vec2 p3 = b + n;
2170        vec2 p4 = b - n;
2171
2172
2173        const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
2174        const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
2175        const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
2176        const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
2177
2178        if (!quickRejectNoScissor(left, top, right, bottom)) {
2179            if (!isAA) {
2180                if (prevVertex != NULL) {
2181                    // Issue two repeat vertices to create degenerate triangles to bridge
2182                    // between the previous line and the new one. This is necessary because
2183                    // we are creating a single triangle_strip which will contain
2184                    // potentially discontinuous line segments.
2185                    Vertex::set(vertices++, prevVertex->position[0], prevVertex->position[1]);
2186                    Vertex::set(vertices++, p1.x, p1.y);
2187                    generatedVerticesCount += 2;
2188                }
2189
2190                Vertex::set(vertices++, p1.x, p1.y);
2191                Vertex::set(vertices++, p2.x, p2.y);
2192                Vertex::set(vertices++, p4.x, p4.y);
2193                Vertex::set(vertices++, p3.x, p3.y);
2194
2195                prevVertex = vertices - 1;
2196                generatedVerticesCount += 4;
2197            } else {
2198                if (!isHairLine && scaled) {
2199                    // Must set width proportions per-segment for scaled non-hairlines to use the
2200                    // correct AA boundary dimensions
2201                    if (boundaryWidthSlot < 0) {
2202                        boundaryWidthSlot =
2203                                mCaches.currentProgram->getUniform("boundaryWidth");
2204                    }
2205
2206                    glUniform1f(boundaryWidthSlot, boundaryWidthProportion);
2207                }
2208
2209                if (boundaryLengthSlot < 0) {
2210                    boundaryLengthSlot = mCaches.currentProgram->getUniform("boundaryLength");
2211                }
2212
2213                glUniform1f(boundaryLengthSlot, boundaryLengthProportion);
2214
2215                if (prevAAVertex != NULL) {
2216                    // Issue two repeat vertices to create degenerate triangles to bridge
2217                    // between the previous line and the new one. This is necessary because
2218                    // we are creating a single triangle_strip which will contain
2219                    // potentially discontinuous line segments.
2220                    AAVertex::set(aaVertices++,prevAAVertex->position[0],
2221                            prevAAVertex->position[1], prevAAVertex->width, prevAAVertex->length);
2222                    AAVertex::set(aaVertices++, p4.x, p4.y, 1, 1);
2223                    generatedVerticesCount += 2;
2224                }
2225
2226                AAVertex::set(aaVertices++, p4.x, p4.y, 1, 1);
2227                AAVertex::set(aaVertices++, p1.x, p1.y, 1, 0);
2228                AAVertex::set(aaVertices++, p3.x, p3.y, 0, 1);
2229                AAVertex::set(aaVertices++, p2.x, p2.y, 0, 0);
2230
2231                prevAAVertex = aaVertices - 1;
2232                generatedVerticesCount += 4;
2233            }
2234
2235            dirtyLayer(a.x == b.x ? left - 1 : left, a.y == b.y ? top - 1 : top,
2236                    a.x == b.x ? right: right, a.y == b.y ? bottom: bottom,
2237                    *mSnapshot->transform);
2238        }
2239    }
2240
2241    if (generatedVerticesCount > 0) {
2242       glDrawArrays(GL_TRIANGLE_STRIP, 0, generatedVerticesCount);
2243    }
2244
2245    if (isAA) {
2246        finishDrawAALine(widthSlot, lengthSlot);
2247    }
2248
2249    return DrawGlInfo::kStatusDrew;
2250}
2251
2252status_t OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) {
2253    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2254
2255    // TODO: The paint's cap style defines whether the points are square or circular
2256    // TODO: Handle AA for round points
2257
2258    // A stroke width of 0 has a special meaning in Skia:
2259    // it draws an unscaled 1px point
2260    float strokeWidth = paint->getStrokeWidth();
2261    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
2262    if (isHairLine) {
2263        // Now that we know it's hairline, we can set the effective width, to be used later
2264        strokeWidth = 1.0f;
2265    }
2266    const float halfWidth = strokeWidth / 2;
2267    int alpha;
2268    SkXfermode::Mode mode;
2269    getAlphaAndMode(paint, &alpha, &mode);
2270
2271    int verticesCount = count >> 1;
2272    int generatedVerticesCount = 0;
2273
2274    TextureVertex pointsData[verticesCount];
2275    TextureVertex* vertex = &pointsData[0];
2276
2277    // TODO: We should optimize this method to not generate vertices for points
2278    // that lie outside of the clip.
2279    mCaches.enableScissor();
2280
2281    setupDraw();
2282    setupDrawNoTexture();
2283    setupDrawPoint(strokeWidth);
2284    setupDrawColor(paint->getColor(), alpha);
2285    setupDrawColorFilter();
2286    setupDrawShader();
2287    setupDrawBlending(mode);
2288    setupDrawProgram();
2289    setupDrawModelViewIdentity(true);
2290    setupDrawColorUniforms();
2291    setupDrawColorFilterUniforms();
2292    setupDrawPointUniforms();
2293    setupDrawShaderIdentityUniforms();
2294    setupDrawMesh(vertex);
2295
2296    for (int i = 0; i < count; i += 2) {
2297        TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
2298        generatedVerticesCount++;
2299
2300        float left = points[i] - halfWidth;
2301        float right = points[i] + halfWidth;
2302        float top = points[i + 1] - halfWidth;
2303        float bottom = points [i + 1] + halfWidth;
2304
2305        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
2306    }
2307
2308    glDrawArrays(GL_POINTS, 0, generatedVerticesCount);
2309
2310    return DrawGlInfo::kStatusDrew;
2311}
2312
2313status_t OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
2314    // No need to check against the clip, we fill the clip region
2315    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2316
2317    Rect& clip(*mSnapshot->clipRect);
2318    clip.snapToPixelBoundaries();
2319
2320    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
2321
2322    return DrawGlInfo::kStatusDrew;
2323}
2324
2325status_t OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture,
2326        SkPaint* paint) {
2327    if (!texture) return DrawGlInfo::kStatusDone;
2328    const AutoTexture autoCleanup(texture);
2329
2330    const float x = left + texture->left - texture->offset;
2331    const float y = top + texture->top - texture->offset;
2332
2333    drawPathTexture(texture, x, y, paint);
2334
2335    return DrawGlInfo::kStatusDrew;
2336}
2337
2338status_t OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
2339        float rx, float ry, SkPaint* p) {
2340    if (mSnapshot->isIgnored() || quickReject(left, top, right, bottom)) {
2341        return DrawGlInfo::kStatusDone;
2342    }
2343
2344    if (p->getStyle() != SkPaint::kFill_Style) {
2345        mCaches.activeTexture(0);
2346        const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
2347                right - left, bottom - top, rx, ry, p);
2348        return drawShape(left, top, texture, p);
2349    }
2350
2351    SkPath path;
2352    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2353    path.addRoundRect(rect, rx, ry);
2354    drawConvexPath(path, p->getColor(), getXfermode(p->getXfermode()), p->isAntiAlias());
2355
2356    return DrawGlInfo::kStatusDrew;
2357}
2358
2359status_t OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* p) {
2360    if (mSnapshot->isIgnored() || quickReject(x - radius, y - radius, x + radius, y + radius)) {
2361        return DrawGlInfo::kStatusDone;
2362    }
2363
2364    if (p->getStyle() != SkPaint::kFill_Style) {
2365        mCaches.activeTexture(0);
2366        const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, p);
2367        return drawShape(x - radius, y - radius, texture, p);
2368    }
2369
2370    SkPath path;
2371    path.addCircle(x, y, radius);
2372    drawConvexPath(path, p->getColor(), getXfermode(p->getXfermode()), p->isAntiAlias());
2373
2374    return DrawGlInfo::kStatusDrew;
2375}
2376
2377status_t OpenGLRenderer::drawOval(float left, float top, float right, float bottom,
2378        SkPaint* p) {
2379    if (mSnapshot->isIgnored() || quickReject(left, top, right, bottom)) {
2380        return DrawGlInfo::kStatusDone;
2381    }
2382
2383    if (p->getStyle() != SkPaint::kFill_Style) {
2384        mCaches.activeTexture(0);
2385        const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, p);
2386        return drawShape(left, top, texture, p);
2387    }
2388
2389    SkPath path;
2390    SkRect rect = SkRect::MakeLTRB(left, top, right, bottom);
2391    path.addOval(rect);
2392    drawConvexPath(path, p->getColor(), getXfermode(p->getXfermode()), p->isAntiAlias());
2393
2394    return DrawGlInfo::kStatusDrew;
2395}
2396
2397status_t OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2398        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
2399    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2400
2401    if (fabs(sweepAngle) >= 360.0f) {
2402        return drawOval(left, top, right, bottom, paint);
2403    }
2404
2405    mCaches.activeTexture(0);
2406    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
2407            startAngle, sweepAngle, useCenter, paint);
2408    return drawShape(left, top, texture, paint);
2409}
2410
2411status_t OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
2412    if (mSnapshot->isIgnored() || quickReject(left, top, right, bottom)) {
2413        return DrawGlInfo::kStatusDone;
2414    }
2415
2416    if (p->getStyle() != SkPaint::kFill_Style) {
2417        mCaches.activeTexture(0);
2418        const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, p);
2419        return drawShape(left, top, texture, p);
2420    }
2421
2422    if (p->isAntiAlias() && !mSnapshot->transform->isSimple()) {
2423        SkPath path;
2424        path.addRect(left, top, right, bottom);
2425        drawConvexPath(path, p->getColor(), getXfermode(p->getXfermode()), true);
2426    } else {
2427        drawColorRect(left, top, right, bottom, p->getColor(), getXfermode(p->getXfermode()));
2428    }
2429
2430    return DrawGlInfo::kStatusDrew;
2431}
2432
2433void OpenGLRenderer::drawTextShadow(SkPaint* paint, const char* text, int bytesCount, int count,
2434        const float* positions, FontRenderer& fontRenderer, int alpha, SkXfermode::Mode mode,
2435        float x, float y) {
2436    mCaches.activeTexture(0);
2437
2438    // NOTE: The drop shadow will not perform gamma correction
2439    //       if shader-based correction is enabled
2440    mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2441    const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2442            paint, text, bytesCount, count, mShadowRadius, positions);
2443    const AutoTexture autoCleanup(shadow);
2444
2445    const float sx = x - shadow->left + mShadowDx;
2446    const float sy = y - shadow->top + mShadowDy;
2447
2448    const int shadowAlpha = ((mShadowColor >> 24) & 0xFF) * mSnapshot->alpha;
2449    int shadowColor = mShadowColor;
2450    if (mShader) {
2451        shadowColor = 0xffffffff;
2452    }
2453
2454    setupDraw();
2455    setupDrawWithTexture(true);
2456    setupDrawAlpha8Color(shadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
2457    setupDrawColorFilter();
2458    setupDrawShader();
2459    setupDrawBlending(true, mode);
2460    setupDrawProgram();
2461    setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height);
2462    setupDrawTexture(shadow->id);
2463    setupDrawPureColorUniforms();
2464    setupDrawColorFilterUniforms();
2465    setupDrawShaderUniforms();
2466    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2467
2468    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2469}
2470
2471status_t OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2472        const float* positions, SkPaint* paint) {
2473    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2474            (paint->getAlpha() * mSnapshot->alpha == 0 && paint->getXfermode() == NULL)) {
2475        return DrawGlInfo::kStatusDone;
2476    }
2477
2478    // NOTE: Skia does not support perspective transform on drawPosText yet
2479    if (!mSnapshot->transform->isSimple()) {
2480        return DrawGlInfo::kStatusDone;
2481    }
2482
2483    float x = 0.0f;
2484    float y = 0.0f;
2485    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
2486    if (pureTranslate) {
2487        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2488        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2489    }
2490
2491    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2492    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2493            paint->getTextSize());
2494
2495    int alpha;
2496    SkXfermode::Mode mode;
2497    getAlphaAndMode(paint, &alpha, &mode);
2498
2499    if (CC_UNLIKELY(mHasShadow)) {
2500        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer, alpha, mode,
2501                0.0f, 0.0f);
2502    }
2503
2504    // Pick the appropriate texture filtering
2505    bool linearFilter = mSnapshot->transform->changesBounds();
2506    if (pureTranslate && !linearFilter) {
2507        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2508    }
2509
2510    mCaches.activeTexture(0);
2511    setupDraw();
2512    setupDrawTextGamma(paint);
2513    setupDrawDirtyRegionsDisabled();
2514    setupDrawWithTexture(true);
2515    setupDrawAlpha8Color(paint->getColor(), alpha);
2516    setupDrawColorFilter();
2517    setupDrawShader();
2518    setupDrawBlending(true, mode);
2519    setupDrawProgram();
2520    setupDrawModelView(x, y, x, y, pureTranslate, true);
2521    setupDrawTexture(fontRenderer.getTexture(linearFilter));
2522    setupDrawPureColorUniforms();
2523    setupDrawColorFilterUniforms();
2524    setupDrawShaderUniforms(pureTranslate);
2525    setupDrawTextGammaUniforms();
2526
2527    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2528    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2529
2530    const bool hasActiveLayer = hasLayer();
2531
2532    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2533            positions, hasActiveLayer ? &bounds : NULL)) {
2534        if (hasActiveLayer) {
2535            if (!pureTranslate) {
2536                mSnapshot->transform->mapRect(bounds);
2537            }
2538            dirtyLayerUnchecked(bounds, getRegion());
2539        }
2540    }
2541
2542    return DrawGlInfo::kStatusDrew;
2543}
2544
2545status_t OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
2546        float x, float y, const float* positions, SkPaint* paint, float length) {
2547    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2548            (paint->getAlpha() * mSnapshot->alpha == 0 && paint->getXfermode() == NULL)) {
2549        return DrawGlInfo::kStatusDone;
2550    }
2551
2552    if (length < 0.0f) length = paint->measureText(text, bytesCount);
2553    switch (paint->getTextAlign()) {
2554        case SkPaint::kCenter_Align:
2555            x -= length / 2.0f;
2556            break;
2557        case SkPaint::kRight_Align:
2558            x -= length;
2559            break;
2560        default:
2561            break;
2562    }
2563
2564    SkPaint::FontMetrics metrics;
2565    paint->getFontMetrics(&metrics, 0.0f);
2566    if (quickReject(x, y + metrics.fTop, x + length, y + metrics.fBottom)) {
2567        return DrawGlInfo::kStatusDone;
2568    }
2569
2570    const float oldX = x;
2571    const float oldY = y;
2572    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
2573    if (CC_LIKELY(pureTranslate)) {
2574        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2575        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2576    }
2577
2578#if DEBUG_GLYPHS
2579    ALOGD("OpenGLRenderer drawText() with FontID=%d",
2580            SkTypeface::UniqueID(paint->getTypeface()));
2581#endif
2582
2583    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2584    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2585            paint->getTextSize());
2586
2587    int alpha;
2588    SkXfermode::Mode mode;
2589    getAlphaAndMode(paint, &alpha, &mode);
2590
2591    if (CC_UNLIKELY(mHasShadow)) {
2592        drawTextShadow(paint, text, bytesCount, count, positions, fontRenderer, alpha, mode,
2593                oldX, oldY);
2594    }
2595
2596    // Pick the appropriate texture filtering
2597    bool linearFilter = mSnapshot->transform->changesBounds();
2598    if (pureTranslate && !linearFilter) {
2599        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2600    }
2601
2602    // The font renderer will always use texture unit 0
2603    mCaches.activeTexture(0);
2604    setupDraw();
2605    setupDrawTextGamma(paint);
2606    setupDrawDirtyRegionsDisabled();
2607    setupDrawWithTexture(true);
2608    setupDrawAlpha8Color(paint->getColor(), alpha);
2609    setupDrawColorFilter();
2610    setupDrawShader();
2611    setupDrawBlending(true, mode);
2612    setupDrawProgram();
2613    setupDrawModelView(x, y, x, y, pureTranslate, true);
2614    // See comment above; the font renderer must use texture unit 0
2615    // assert(mTextureUnit == 0)
2616    setupDrawTexture(fontRenderer.getTexture(linearFilter));
2617    setupDrawPureColorUniforms();
2618    setupDrawColorFilterUniforms();
2619    setupDrawShaderUniforms(pureTranslate);
2620    setupDrawTextGammaUniforms();
2621
2622    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2623    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2624
2625    const bool hasActiveLayer = hasLayer();
2626
2627    bool status;
2628    if (paint->getTextAlign() != SkPaint::kLeft_Align) {
2629        SkPaint paintCopy(*paint);
2630        paintCopy.setTextAlign(SkPaint::kLeft_Align);
2631        status = fontRenderer.renderPosText(&paintCopy, clip, text, 0, bytesCount, count, x, y,
2632            positions, hasActiveLayer ? &bounds : NULL);
2633    } else {
2634        status = fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2635            positions, hasActiveLayer ? &bounds : NULL);
2636    }
2637
2638    if (status && hasActiveLayer) {
2639        if (!pureTranslate) {
2640            mSnapshot->transform->mapRect(bounds);
2641        }
2642        dirtyLayerUnchecked(bounds, getRegion());
2643    }
2644
2645    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
2646
2647    return DrawGlInfo::kStatusDrew;
2648}
2649
2650status_t OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count, SkPath* path,
2651        float hOffset, float vOffset, SkPaint* paint) {
2652    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2653            (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
2654        return DrawGlInfo::kStatusDone;
2655    }
2656
2657    FontRenderer& fontRenderer = mCaches.fontRenderer->getFontRenderer(paint);
2658    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2659            paint->getTextSize());
2660
2661    int alpha;
2662    SkXfermode::Mode mode;
2663    getAlphaAndMode(paint, &alpha, &mode);
2664
2665    mCaches.activeTexture(0);
2666    setupDraw();
2667    setupDrawTextGamma(paint);
2668    setupDrawDirtyRegionsDisabled();
2669    setupDrawWithTexture(true);
2670    setupDrawAlpha8Color(paint->getColor(), alpha);
2671    setupDrawColorFilter();
2672    setupDrawShader();
2673    setupDrawBlending(true, mode);
2674    setupDrawProgram();
2675    setupDrawModelView(0.0f, 0.0f, 0.0f, 0.0f, false, true);
2676    setupDrawTexture(fontRenderer.getTexture(true));
2677    setupDrawPureColorUniforms();
2678    setupDrawColorFilterUniforms();
2679    setupDrawShaderUniforms(false);
2680    setupDrawTextGammaUniforms();
2681
2682    const Rect* clip = &mSnapshot->getLocalClip();
2683    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2684
2685    const bool hasActiveLayer = hasLayer();
2686
2687    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2688            hOffset, vOffset, hasActiveLayer ? &bounds : NULL)) {
2689        if (hasActiveLayer) {
2690            mSnapshot->transform->mapRect(bounds);
2691            dirtyLayerUnchecked(bounds, getRegion());
2692        }
2693    }
2694
2695    return DrawGlInfo::kStatusDrew;
2696}
2697
2698status_t OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
2699    if (mSnapshot->isIgnored()) return DrawGlInfo::kStatusDone;
2700
2701    mCaches.activeTexture(0);
2702
2703    // TODO: Perform early clip test before we rasterize the path
2704    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2705    if (!texture) return DrawGlInfo::kStatusDone;
2706    const AutoTexture autoCleanup(texture);
2707
2708    const float x = texture->left - texture->offset;
2709    const float y = texture->top - texture->offset;
2710
2711    drawPathTexture(texture, x, y, paint);
2712
2713    return DrawGlInfo::kStatusDrew;
2714}
2715
2716status_t OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
2717    if (!layer) {
2718        return DrawGlInfo::kStatusDone;
2719    }
2720
2721    Rect transformed;
2722    Rect clip;
2723    const bool rejected = quickRejectNoScissor(x, y,
2724            x + layer->layer.getWidth(), y + layer->layer.getHeight(), transformed, clip);
2725
2726    if (rejected) {
2727        return DrawGlInfo::kStatusDone;
2728    }
2729
2730    bool debugLayerUpdate = false;
2731    if (updateLayer(layer, true)) {
2732        debugLayerUpdate = mCaches.debugLayersUpdates;
2733    }
2734
2735    mCaches.setScissorEnabled(mScissorOptimizationDisabled || !clip.contains(transformed));
2736    mCaches.activeTexture(0);
2737
2738    if (CC_LIKELY(!layer->region.isEmpty())) {
2739        SkiaColorFilter* oldFilter = mColorFilter;
2740        mColorFilter = layer->getColorFilter();
2741
2742        if (layer->region.isRect()) {
2743            composeLayerRect(layer, layer->regionRect);
2744        } else if (layer->mesh) {
2745            const float a = layer->getAlpha() / 255.0f;
2746            setupDraw();
2747            setupDrawWithTexture();
2748            setupDrawColor(a, a, a, a);
2749            setupDrawColorFilter();
2750            setupDrawBlending(layer->isBlend() || a < 1.0f, layer->getMode(), false);
2751            setupDrawProgram();
2752            setupDrawPureColorUniforms();
2753            setupDrawColorFilterUniforms();
2754            setupDrawTexture(layer->getTexture());
2755            if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
2756                int tx = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2757                int ty = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2758
2759                layer->setFilter(GL_NEAREST);
2760                setupDrawModelViewTranslate(tx, ty,
2761                        tx + layer->layer.getWidth(), ty + layer->layer.getHeight(), true);
2762            } else {
2763                layer->setFilter(GL_LINEAR);
2764                setupDrawModelViewTranslate(x, y,
2765                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
2766            }
2767            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
2768
2769            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
2770                    GL_UNSIGNED_SHORT, layer->meshIndices);
2771
2772            finishDrawTexture();
2773
2774#if DEBUG_LAYERS_AS_REGIONS
2775            drawRegionRects(layer->region);
2776#endif
2777        }
2778
2779        mColorFilter = oldFilter;
2780
2781        if (debugLayerUpdate) {
2782            drawColorRect(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight(),
2783                    0x7f00ff00, SkXfermode::kSrcOver_Mode);
2784        }
2785    }
2786
2787    return DrawGlInfo::kStatusDrew;
2788}
2789
2790///////////////////////////////////////////////////////////////////////////////
2791// Shaders
2792///////////////////////////////////////////////////////////////////////////////
2793
2794void OpenGLRenderer::resetShader() {
2795    mShader = NULL;
2796}
2797
2798void OpenGLRenderer::setupShader(SkiaShader* shader) {
2799    mShader = shader;
2800    if (mShader) {
2801        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
2802    }
2803}
2804
2805///////////////////////////////////////////////////////////////////////////////
2806// Color filters
2807///////////////////////////////////////////////////////////////////////////////
2808
2809void OpenGLRenderer::resetColorFilter() {
2810    mColorFilter = NULL;
2811}
2812
2813void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
2814    mColorFilter = filter;
2815}
2816
2817///////////////////////////////////////////////////////////////////////////////
2818// Drop shadow
2819///////////////////////////////////////////////////////////////////////////////
2820
2821void OpenGLRenderer::resetShadow() {
2822    mHasShadow = false;
2823}
2824
2825void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
2826    mHasShadow = true;
2827    mShadowRadius = radius;
2828    mShadowDx = dx;
2829    mShadowDy = dy;
2830    mShadowColor = color;
2831}
2832
2833///////////////////////////////////////////////////////////////////////////////
2834// Draw filters
2835///////////////////////////////////////////////////////////////////////////////
2836
2837void OpenGLRenderer::resetPaintFilter() {
2838    mHasDrawFilter = false;
2839}
2840
2841void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
2842    mHasDrawFilter = true;
2843    mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
2844    mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
2845}
2846
2847SkPaint* OpenGLRenderer::filterPaint(SkPaint* paint) {
2848    if (CC_LIKELY(!mHasDrawFilter || !paint)) return paint;
2849
2850    uint32_t flags = paint->getFlags();
2851
2852    mFilteredPaint = *paint;
2853    mFilteredPaint.setFlags((flags & ~mPaintFilterClearBits) | mPaintFilterSetBits);
2854
2855    return &mFilteredPaint;
2856}
2857
2858///////////////////////////////////////////////////////////////////////////////
2859// Drawing implementation
2860///////////////////////////////////////////////////////////////////////////////
2861
2862void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
2863        float x, float y, SkPaint* paint) {
2864    if (quickReject(x, y, x + texture->width, y + texture->height)) {
2865        return;
2866    }
2867
2868    int alpha;
2869    SkXfermode::Mode mode;
2870    getAlphaAndMode(paint, &alpha, &mode);
2871
2872    setupDraw();
2873    setupDrawWithTexture(true);
2874    setupDrawAlpha8Color(paint->getColor(), alpha);
2875    setupDrawColorFilter();
2876    setupDrawShader();
2877    setupDrawBlending(true, mode);
2878    setupDrawProgram();
2879    setupDrawModelView(x, y, x + texture->width, y + texture->height);
2880    setupDrawTexture(texture->id);
2881    setupDrawPureColorUniforms();
2882    setupDrawColorFilterUniforms();
2883    setupDrawShaderUniforms();
2884    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2885
2886    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2887
2888    finishDrawTexture();
2889}
2890
2891// Same values used by Skia
2892#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
2893#define kStdUnderline_Offset    (1.0f / 9.0f)
2894#define kStdUnderline_Thickness (1.0f / 18.0f)
2895
2896void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
2897        float x, float y, SkPaint* paint) {
2898    // Handle underline and strike-through
2899    uint32_t flags = paint->getFlags();
2900    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
2901        SkPaint paintCopy(*paint);
2902        float underlineWidth = length;
2903        // If length is > 0.0f, we already measured the text for the text alignment
2904        if (length <= 0.0f) {
2905            underlineWidth = paintCopy.measureText(text, bytesCount);
2906        }
2907
2908        if (CC_LIKELY(underlineWidth > 0.0f)) {
2909            const float textSize = paintCopy.getTextSize();
2910            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
2911
2912            const float left = x;
2913            float top = 0.0f;
2914
2915            int linesCount = 0;
2916            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
2917            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
2918
2919            const int pointsCount = 4 * linesCount;
2920            float points[pointsCount];
2921            int currentPoint = 0;
2922
2923            if (flags & SkPaint::kUnderlineText_Flag) {
2924                top = y + textSize * kStdUnderline_Offset;
2925                points[currentPoint++] = left;
2926                points[currentPoint++] = top;
2927                points[currentPoint++] = left + underlineWidth;
2928                points[currentPoint++] = top;
2929            }
2930
2931            if (flags & SkPaint::kStrikeThruText_Flag) {
2932                top = y + textSize * kStdStrikeThru_Offset;
2933                points[currentPoint++] = left;
2934                points[currentPoint++] = top;
2935                points[currentPoint++] = left + underlineWidth;
2936                points[currentPoint++] = top;
2937            }
2938
2939            paintCopy.setStrokeWidth(strokeWidth);
2940
2941            drawLines(&points[0], pointsCount, &paintCopy);
2942        }
2943    }
2944}
2945
2946void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
2947        int color, SkXfermode::Mode mode, bool ignoreTransform) {
2948    // If a shader is set, preserve only the alpha
2949    if (mShader) {
2950        color |= 0x00ffffff;
2951    }
2952
2953    setupDraw();
2954    setupDrawNoTexture();
2955    setupDrawColor(color, ((color >> 24) & 0xFF) * mSnapshot->alpha);
2956    setupDrawShader();
2957    setupDrawColorFilter();
2958    setupDrawBlending(mode);
2959    setupDrawProgram();
2960    setupDrawModelView(left, top, right, bottom, ignoreTransform);
2961    setupDrawColorUniforms();
2962    setupDrawShaderUniforms(ignoreTransform);
2963    setupDrawColorFilterUniforms();
2964    setupDrawSimpleMesh();
2965
2966    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2967}
2968
2969void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2970        Texture* texture, SkPaint* paint) {
2971    int alpha;
2972    SkXfermode::Mode mode;
2973    getAlphaAndMode(paint, &alpha, &mode);
2974
2975    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2976
2977    if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
2978        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
2979        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
2980
2981        texture->setFilter(GL_NEAREST, true);
2982        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
2983                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
2984                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
2985    } else {
2986        texture->setFilter(FILTER(paint), true);
2987        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
2988                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
2989                GL_TRIANGLE_STRIP, gMeshCount);
2990    }
2991}
2992
2993void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2994        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
2995    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
2996            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
2997}
2998
2999void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
3000        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
3001        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
3002        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
3003
3004    setupDraw();
3005    setupDrawWithTexture();
3006    setupDrawColor(alpha, alpha, alpha, alpha);
3007    setupDrawColorFilter();
3008    setupDrawBlending(blend, mode, swapSrcDst);
3009    setupDrawProgram();
3010    if (!dirty) {
3011        setupDrawDirtyRegionsDisabled();
3012    }
3013    if (!ignoreScale) {
3014        setupDrawModelView(left, top, right, bottom, ignoreTransform);
3015    } else {
3016        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
3017    }
3018    setupDrawPureColorUniforms();
3019    setupDrawColorFilterUniforms();
3020    setupDrawTexture(texture);
3021    setupDrawMesh(vertices, texCoords, vbo);
3022
3023    glDrawArrays(drawMode, 0, elementsCount);
3024
3025    finishDrawTexture();
3026}
3027
3028void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
3029        ProgramDescription& description, bool swapSrcDst) {
3030    blend = blend || mode != SkXfermode::kSrcOver_Mode;
3031
3032    if (blend) {
3033        // These blend modes are not supported by OpenGL directly and have
3034        // to be implemented using shaders. Since the shader will perform
3035        // the blending, turn blending off here
3036        // If the blend mode cannot be implemented using shaders, fall
3037        // back to the default SrcOver blend mode instead
3038        if (CC_UNLIKELY(mode > SkXfermode::kScreen_Mode)) {
3039            if (CC_UNLIKELY(mCaches.extensions.hasFramebufferFetch())) {
3040                description.framebufferMode = mode;
3041                description.swapSrcDst = swapSrcDst;
3042
3043                if (mCaches.blend) {
3044                    glDisable(GL_BLEND);
3045                    mCaches.blend = false;
3046                }
3047
3048                return;
3049            } else {
3050                mode = SkXfermode::kSrcOver_Mode;
3051            }
3052        }
3053
3054        if (!mCaches.blend) {
3055            glEnable(GL_BLEND);
3056        }
3057
3058        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
3059        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
3060
3061        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
3062            glBlendFunc(sourceMode, destMode);
3063            mCaches.lastSrcMode = sourceMode;
3064            mCaches.lastDstMode = destMode;
3065        }
3066    } else if (mCaches.blend) {
3067        glDisable(GL_BLEND);
3068    }
3069    mCaches.blend = blend;
3070}
3071
3072bool OpenGLRenderer::useProgram(Program* program) {
3073    if (!program->isInUse()) {
3074        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
3075        program->use();
3076        mCaches.currentProgram = program;
3077        return false;
3078    }
3079    return true;
3080}
3081
3082void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
3083    TextureVertex* v = &mMeshVertices[0];
3084    TextureVertex::setUV(v++, u1, v1);
3085    TextureVertex::setUV(v++, u2, v1);
3086    TextureVertex::setUV(v++, u1, v2);
3087    TextureVertex::setUV(v++, u2, v2);
3088}
3089
3090void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
3091    getAlphaAndModeDirect(paint, alpha,  mode);
3092    *alpha *= mSnapshot->alpha;
3093}
3094
3095}; // namespace uirenderer
3096}; // namespace android
3097