OpenGLRenderer.cpp revision 6217a71cd281003a376d998269d577d26a61c206 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkTypeface.h>
25
26#include <utils/Log.h>
27#include <utils/StopWatch.h>
28
29#include <ui/Rect.h>
30
31#include "OpenGLRenderer.h"
32#include "DisplayListRenderer.h"
33#include "Vector.h"
34
35namespace android {
36namespace uirenderer {
37
38///////////////////////////////////////////////////////////////////////////////
39// Defines
40///////////////////////////////////////////////////////////////////////////////
41
42#define RAD_TO_DEG (180.0f / 3.14159265f)
43#define MIN_ANGLE 0.001f
44
45// TODO: This should be set in properties
46#define ALPHA_THRESHOLD (0x7f / PANEL_BIT_DEPTH)
47
48///////////////////////////////////////////////////////////////////////////////
49// Globals
50///////////////////////////////////////////////////////////////////////////////
51
52/**
53 * Structure mapping Skia xfermodes to OpenGL blending factors.
54 */
55struct Blender {
56    SkXfermode::Mode mode;
57    GLenum src;
58    GLenum dst;
59}; // struct Blender
60
61// In this array, the index of each Blender equals the value of the first
62// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
63static const Blender gBlends[] = {
64    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
65    { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
66    { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
67    { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
68    { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
69    { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
70    { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
71    { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
72    { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
73    { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
74    { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
75    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
76};
77
78// This array contains the swapped version of each SkXfermode. For instance
79// this array's SrcOver blending mode is actually DstOver. You can refer to
80// createLayer() for more information on the purpose of this array.
81static const Blender gBlendsSwap[] = {
82    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
83    { SkXfermode::kSrc_Mode,     GL_ZERO,                 GL_ONE },
84    { SkXfermode::kDst_Mode,     GL_ONE,                  GL_ZERO },
85    { SkXfermode::kSrcOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
86    { SkXfermode::kDstOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
87    { SkXfermode::kSrcIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
88    { SkXfermode::kDstIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
89    { SkXfermode::kSrcOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
90    { SkXfermode::kDstOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
91    { SkXfermode::kSrcATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
92    { SkXfermode::kDstATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
93    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
94};
95
96static const GLenum gTextureUnits[] = {
97    GL_TEXTURE0,
98    GL_TEXTURE1,
99    GL_TEXTURE2
100};
101
102///////////////////////////////////////////////////////////////////////////////
103// Constructors/destructor
104///////////////////////////////////////////////////////////////////////////////
105
106OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
107    mShader = NULL;
108    mColorFilter = NULL;
109    mHasShadow = false;
110
111    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
112
113    mFirstSnapshot = new Snapshot;
114}
115
116OpenGLRenderer::~OpenGLRenderer() {
117    // The context has already been destroyed at this point, do not call
118    // GL APIs. All GL state should be kept in Caches.h
119}
120
121///////////////////////////////////////////////////////////////////////////////
122// Setup
123///////////////////////////////////////////////////////////////////////////////
124
125void OpenGLRenderer::setViewport(int width, int height) {
126    glViewport(0, 0, width, height);
127    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
128
129    mWidth = width;
130    mHeight = height;
131
132    mFirstSnapshot->height = height;
133    mFirstSnapshot->viewport.set(0, 0, width, height);
134
135    mDirtyClip = false;
136}
137
138void OpenGLRenderer::prepare(bool opaque) {
139    prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
140}
141
142void OpenGLRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
143    mCaches.clearGarbage();
144
145    mSnapshot = new Snapshot(mFirstSnapshot,
146            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
147    mSnapshot->fbo = getTargetFbo();
148
149    mSaveCount = 1;
150
151    glViewport(0, 0, mWidth, mHeight);
152
153    glDisable(GL_DITHER);
154
155    glEnable(GL_SCISSOR_TEST);
156    glScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
157    mSnapshot->setClip(left, top, right, bottom);
158
159    if (!opaque) {
160        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
161        glClear(GL_COLOR_BUFFER_BIT);
162    }
163}
164
165void OpenGLRenderer::finish() {
166#if DEBUG_OPENGL
167    GLenum status = GL_NO_ERROR;
168    while ((status = glGetError()) != GL_NO_ERROR) {
169        LOGD("GL error from OpenGLRenderer: 0x%x", status);
170        switch (status) {
171            case GL_OUT_OF_MEMORY:
172                LOGE("  OpenGLRenderer is out of memory!");
173                break;
174        }
175    }
176#endif
177#if DEBUG_MEMORY_USAGE
178    mCaches.dumpMemoryUsage();
179#else
180    if (mCaches.getDebugLevel() & kDebugMemory) {
181        mCaches.dumpMemoryUsage();
182    }
183#endif
184}
185
186void OpenGLRenderer::interrupt() {
187    if (mCaches.currentProgram) {
188        if (mCaches.currentProgram->isInUse()) {
189            mCaches.currentProgram->remove();
190            mCaches.currentProgram = NULL;
191        }
192    }
193    mCaches.unbindMeshBuffer();
194}
195
196void OpenGLRenderer::resume() {
197    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
198
199    glEnable(GL_SCISSOR_TEST);
200    dirtyClip();
201
202    glDisable(GL_DITHER);
203
204    glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
205    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
206
207    mCaches.blend = true;
208    glEnable(GL_BLEND);
209    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
210    glBlendEquation(GL_FUNC_ADD);
211}
212
213bool OpenGLRenderer::callDrawGLFunction(Functor *functor, Rect& dirty) {
214    interrupt();
215    if (mDirtyClip) {
216        setScissorFromClip();
217    }
218
219#if RENDER_LAYERS_AS_REGIONS
220    // Since we don't know what the functor will draw, let's dirty
221    // tne entire clip region
222    if (hasLayer()) {
223        Rect clip(*mSnapshot->clipRect);
224        clip.snapToPixelBoundaries();
225        dirtyLayerUnchecked(clip, getRegion());
226    }
227#endif
228
229    float bounds[4];
230    status_t result = (*functor)(&bounds[0], 4);
231
232    if (result != 0) {
233        Rect localDirty(bounds[0], bounds[1], bounds[2], bounds[3]);
234        dirty.unionWith(localDirty);
235    }
236
237    resume();
238    return result != 0;
239}
240
241///////////////////////////////////////////////////////////////////////////////
242// State management
243///////////////////////////////////////////////////////////////////////////////
244
245int OpenGLRenderer::getSaveCount() const {
246    return mSaveCount;
247}
248
249int OpenGLRenderer::save(int flags) {
250    return saveSnapshot(flags);
251}
252
253void OpenGLRenderer::restore() {
254    if (mSaveCount > 1) {
255        restoreSnapshot();
256    }
257}
258
259void OpenGLRenderer::restoreToCount(int saveCount) {
260    if (saveCount < 1) saveCount = 1;
261
262    while (mSaveCount > saveCount) {
263        restoreSnapshot();
264    }
265}
266
267int OpenGLRenderer::saveSnapshot(int flags) {
268    mSnapshot = new Snapshot(mSnapshot, flags);
269    return mSaveCount++;
270}
271
272bool OpenGLRenderer::restoreSnapshot() {
273    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
274    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
275    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
276
277    sp<Snapshot> current = mSnapshot;
278    sp<Snapshot> previous = mSnapshot->previous;
279
280    if (restoreOrtho) {
281        Rect& r = previous->viewport;
282        glViewport(r.left, r.top, r.right, r.bottom);
283        mOrthoMatrix.load(current->orthoMatrix);
284    }
285
286    mSaveCount--;
287    mSnapshot = previous;
288
289    if (restoreClip) {
290        dirtyClip();
291    }
292
293    if (restoreLayer) {
294        composeLayer(current, previous);
295    }
296
297    return restoreClip;
298}
299
300///////////////////////////////////////////////////////////////////////////////
301// Layers
302///////////////////////////////////////////////////////////////////////////////
303
304int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
305        SkPaint* p, int flags) {
306    const GLuint previousFbo = mSnapshot->fbo;
307    const int count = saveSnapshot(flags);
308
309    if (!mSnapshot->isIgnored()) {
310        int alpha = 255;
311        SkXfermode::Mode mode;
312
313        if (p) {
314            alpha = p->getAlpha();
315            if (!mCaches.extensions.hasFramebufferFetch()) {
316                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
317                if (!isMode) {
318                    // Assume SRC_OVER
319                    mode = SkXfermode::kSrcOver_Mode;
320                }
321            } else {
322                mode = getXfermode(p->getXfermode());
323            }
324        } else {
325            mode = SkXfermode::kSrcOver_Mode;
326        }
327
328        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
329    }
330
331    return count;
332}
333
334int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
335        int alpha, int flags) {
336    if (alpha >= 255 - ALPHA_THRESHOLD) {
337        return saveLayer(left, top, right, bottom, NULL, flags);
338    } else {
339        SkPaint paint;
340        paint.setAlpha(alpha);
341        return saveLayer(left, top, right, bottom, &paint, flags);
342    }
343}
344
345/**
346 * Layers are viewed by Skia are slightly different than layers in image editing
347 * programs (for instance.) When a layer is created, previously created layers
348 * and the frame buffer still receive every drawing command. For instance, if a
349 * layer is created and a shape intersecting the bounds of the layers and the
350 * framebuffer is draw, the shape will be drawn on both (unless the layer was
351 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
352 *
353 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
354 * texture. Unfortunately, this is inefficient as it requires every primitive to
355 * be drawn n + 1 times, where n is the number of active layers. In practice this
356 * means, for every primitive:
357 *   - Switch active frame buffer
358 *   - Change viewport, clip and projection matrix
359 *   - Issue the drawing
360 *
361 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
362 * To avoid this, layers are implemented in a different way here, at least in the
363 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
364 * is set. When this flag is set we can redirect all drawing operations into a
365 * single FBO.
366 *
367 * This implementation relies on the frame buffer being at least RGBA 8888. When
368 * a layer is created, only a texture is created, not an FBO. The content of the
369 * frame buffer contained within the layer's bounds is copied into this texture
370 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
371 * buffer and drawing continues as normal. This technique therefore treats the
372 * frame buffer as a scratch buffer for the layers.
373 *
374 * To compose the layers back onto the frame buffer, each layer texture
375 * (containing the original frame buffer data) is drawn as a simple quad over
376 * the frame buffer. The trick is that the quad is set as the composition
377 * destination in the blending equation, and the frame buffer becomes the source
378 * of the composition.
379 *
380 * Drawing layers with an alpha value requires an extra step before composition.
381 * An empty quad is drawn over the layer's region in the frame buffer. This quad
382 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
383 * quad is used to multiply the colors in the frame buffer. This is achieved by
384 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
385 * GL_ZERO, GL_SRC_ALPHA.
386 *
387 * Because glCopyTexImage2D() can be slow, an alternative implementation might
388 * be use to draw a single clipped layer. The implementation described above
389 * is correct in every case.
390 *
391 * (1) The frame buffer is actually not cleared right away. To allow the GPU
392 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
393 *     buffer is left untouched until the first drawing operation. Only when
394 *     something actually gets drawn are the layers regions cleared.
395 */
396bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
397        float right, float bottom, int alpha, SkXfermode::Mode mode,
398        int flags, GLuint previousFbo) {
399    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
400    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
401
402    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
403
404    // Window coordinates of the layer
405    Rect bounds(left, top, right, bottom);
406    if (!fboLayer) {
407        mSnapshot->transform->mapRect(bounds);
408
409        // Layers only make sense if they are in the framebuffer's bounds
410        if (bounds.intersect(*snapshot->clipRect)) {
411            // We cannot work with sub-pixels in this case
412            bounds.snapToPixelBoundaries();
413
414            // When the layer is not an FBO, we may use glCopyTexImage so we
415            // need to make sure the layer does not extend outside the bounds
416            // of the framebuffer
417            if (!bounds.intersect(snapshot->previous->viewport)) {
418                bounds.setEmpty();
419            }
420        } else {
421            bounds.setEmpty();
422        }
423    }
424
425    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
426            bounds.getHeight() > mCaches.maxTextureSize) {
427        snapshot->empty = fboLayer;
428    } else {
429        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
430    }
431
432    // Bail out if we won't draw in this snapshot
433    if (snapshot->invisible || snapshot->empty) {
434        return false;
435    }
436
437    glActiveTexture(gTextureUnits[0]);
438    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
439    if (!layer) {
440        return false;
441    }
442
443    layer->mode = mode;
444    layer->alpha = alpha;
445    layer->layer.set(bounds);
446    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
447            bounds.getWidth() / float(layer->width), 0.0f);
448    layer->colorFilter = mColorFilter;
449
450    // Save the layer in the snapshot
451    snapshot->flags |= Snapshot::kFlagIsLayer;
452    snapshot->layer = layer;
453
454    if (fboLayer) {
455        return createFboLayer(layer, bounds, snapshot, previousFbo);
456    } else {
457        // Copy the framebuffer into the layer
458        glBindTexture(GL_TEXTURE_2D, layer->texture);
459        if (!bounds.isEmpty()) {
460            if (layer->empty) {
461                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
462                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
463                layer->empty = false;
464            } else {
465                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
466                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
467            }
468
469            // Clear the framebuffer where the layer will draw
470            glScissor(bounds.left, mSnapshot->height - bounds.bottom,
471                    bounds.getWidth(), bounds.getHeight());
472            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
473            glClear(GL_COLOR_BUFFER_BIT);
474
475            dirtyClip();
476        }
477    }
478
479    return true;
480}
481
482bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
483        GLuint previousFbo) {
484    layer->fbo = mCaches.fboCache.get();
485
486#if RENDER_LAYERS_AS_REGIONS
487    snapshot->region = &snapshot->layer->region;
488    snapshot->flags |= Snapshot::kFlagFboTarget;
489#endif
490
491    Rect clip(bounds);
492    snapshot->transform->mapRect(clip);
493    clip.intersect(*snapshot->clipRect);
494    clip.snapToPixelBoundaries();
495    clip.intersect(snapshot->previous->viewport);
496
497    mat4 inverse;
498    inverse.loadInverse(*mSnapshot->transform);
499
500    inverse.mapRect(clip);
501    clip.snapToPixelBoundaries();
502    clip.intersect(bounds);
503    clip.translate(-bounds.left, -bounds.top);
504
505    snapshot->flags |= Snapshot::kFlagIsFboLayer;
506    snapshot->fbo = layer->fbo;
507    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
508    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
509    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
510    snapshot->height = bounds.getHeight();
511    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
512    snapshot->orthoMatrix.load(mOrthoMatrix);
513
514    // Bind texture to FBO
515    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
516    glBindTexture(GL_TEXTURE_2D, layer->texture);
517
518    // Initialize the texture if needed
519    if (layer->empty) {
520        layer->empty = false;
521        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
522                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
523    }
524
525    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
526            layer->texture, 0);
527
528#if DEBUG_LAYERS_AS_REGIONS
529    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
530    if (status != GL_FRAMEBUFFER_COMPLETE) {
531        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
532
533        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
534        glDeleteTextures(1, &layer->texture);
535        mCaches.fboCache.put(layer->fbo);
536
537        delete layer;
538
539        return false;
540    }
541#endif
542
543    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
544    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
545            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
546    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
547    glClear(GL_COLOR_BUFFER_BIT);
548
549    dirtyClip();
550
551    // Change the ortho projection
552    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
553    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
554
555    return true;
556}
557
558/**
559 * Read the documentation of createLayer() before doing anything in this method.
560 */
561void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
562    if (!current->layer) {
563        LOGE("Attempting to compose a layer that does not exist");
564        return;
565    }
566
567    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
568
569    if (fboLayer) {
570        // Unbind current FBO and restore previous one
571        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
572    }
573
574    Layer* layer = current->layer;
575    const Rect& rect = layer->layer;
576
577    if (!fboLayer && layer->alpha < 255) {
578        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
579                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
580        // Required below, composeLayerRect() will divide by 255
581        layer->alpha = 255;
582    }
583
584    mCaches.unbindMeshBuffer();
585
586    glActiveTexture(gTextureUnits[0]);
587
588    // When the layer is stored in an FBO, we can save a bit of fillrate by
589    // drawing only the dirty region
590    if (fboLayer) {
591        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
592        if (layer->colorFilter) {
593            setupColorFilter(layer->colorFilter);
594        }
595        composeLayerRegion(layer, rect);
596        if (layer->colorFilter) {
597            resetColorFilter();
598        }
599    } else {
600        if (!rect.isEmpty()) {
601            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
602            composeLayerRect(layer, rect, true);
603        }
604    }
605
606    if (fboLayer) {
607        // Detach the texture from the FBO
608        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
609        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
610        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
611
612        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
613        mCaches.fboCache.put(current->fbo);
614    }
615
616    dirtyClip();
617
618    // Failing to add the layer to the cache should happen only if the layer is too large
619    if (!mCaches.layerCache.put(layer)) {
620        LAYER_LOGD("Deleting layer");
621        glDeleteTextures(1, &layer->texture);
622        delete layer;
623    }
624}
625
626void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
627    const Rect& texCoords = layer->texCoords;
628    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
629
630    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
631            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
632            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
633
634    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
635}
636
637void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
638#if RENDER_LAYERS_AS_REGIONS
639#if RENDER_LAYERS_RECT_AS_RECT
640    if (layer->region.isRect()) {
641        composeLayerRect(layer, rect);
642        layer->region.clear();
643        return;
644    }
645#endif
646
647    if (!layer->region.isEmpty()) {
648        size_t count;
649        const android::Rect* rects = layer->region.getArray(&count);
650
651        const float alpha = layer->alpha / 255.0f;
652        const float texX = 1.0f / float(layer->width);
653        const float texY = 1.0f / float(layer->height);
654        const float height = rect.getHeight();
655
656        TextureVertex* mesh = mCaches.getRegionMesh();
657        GLsizei numQuads = 0;
658
659        setupDraw();
660        setupDrawWithTexture();
661        setupDrawColor(alpha, alpha, alpha, alpha);
662        setupDrawColorFilter();
663        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
664        setupDrawProgram();
665        setupDrawDirtyRegionsDisabled();
666        setupDrawPureColorUniforms();
667        setupDrawColorFilterUniforms();
668        setupDrawTexture(layer->texture);
669        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
670        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
671
672        for (size_t i = 0; i < count; i++) {
673            const android::Rect* r = &rects[i];
674
675            const float u1 = r->left * texX;
676            const float v1 = (height - r->top) * texY;
677            const float u2 = r->right * texX;
678            const float v2 = (height - r->bottom) * texY;
679
680            // TODO: Reject quads outside of the clip
681            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
682            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
683            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
684            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
685
686            numQuads++;
687
688            if (numQuads >= REGION_MESH_QUAD_COUNT) {
689                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
690                numQuads = 0;
691                mesh = mCaches.getRegionMesh();
692            }
693        }
694
695        if (numQuads > 0) {
696            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
697        }
698
699        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
700        finishDrawTexture();
701
702#if DEBUG_LAYERS_AS_REGIONS
703        drawRegionRects(layer->region);
704#endif
705
706        layer->region.clear();
707    }
708#else
709    composeLayerRect(layer, rect);
710#endif
711}
712
713void OpenGLRenderer::drawRegionRects(const Region& region) {
714#if DEBUG_LAYERS_AS_REGIONS
715    size_t count;
716    const android::Rect* rects = region.getArray(&count);
717
718    uint32_t colors[] = {
719            0x7fff0000, 0x7f00ff00,
720            0x7f0000ff, 0x7fff00ff,
721    };
722
723    int offset = 0;
724    int32_t top = rects[0].top;
725
726    for (size_t i = 0; i < count; i++) {
727        if (top != rects[i].top) {
728            offset ^= 0x2;
729            top = rects[i].top;
730        }
731
732        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
733        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
734                SkXfermode::kSrcOver_Mode);
735    }
736#endif
737}
738
739void OpenGLRenderer::dirtyLayer(const float left, const float top,
740        const float right, const float bottom, const mat4 transform) {
741#if RENDER_LAYERS_AS_REGIONS
742    if (hasLayer()) {
743        Rect bounds(left, top, right, bottom);
744        transform.mapRect(bounds);
745        dirtyLayerUnchecked(bounds, getRegion());
746    }
747#endif
748}
749
750void OpenGLRenderer::dirtyLayer(const float left, const float top,
751        const float right, const float bottom) {
752#if RENDER_LAYERS_AS_REGIONS
753    if (hasLayer()) {
754        Rect bounds(left, top, right, bottom);
755        dirtyLayerUnchecked(bounds, getRegion());
756    }
757#endif
758}
759
760void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
761#if RENDER_LAYERS_AS_REGIONS
762    if (bounds.intersect(*mSnapshot->clipRect)) {
763        bounds.snapToPixelBoundaries();
764        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
765        if (!dirty.isEmpty()) {
766            region->orSelf(dirty);
767        }
768    }
769#endif
770}
771
772///////////////////////////////////////////////////////////////////////////////
773// Transforms
774///////////////////////////////////////////////////////////////////////////////
775
776void OpenGLRenderer::translate(float dx, float dy) {
777    mSnapshot->transform->translate(dx, dy, 0.0f);
778}
779
780void OpenGLRenderer::rotate(float degrees) {
781    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
782}
783
784void OpenGLRenderer::scale(float sx, float sy) {
785    mSnapshot->transform->scale(sx, sy, 1.0f);
786}
787
788void OpenGLRenderer::skew(float sx, float sy) {
789    mSnapshot->transform->skew(sx, sy);
790}
791
792void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
793    mSnapshot->transform->load(*matrix);
794}
795
796const float* OpenGLRenderer::getMatrix() const {
797    if (mSnapshot->fbo != 0) {
798        return &mSnapshot->transform->data[0];
799    }
800    return &mIdentity.data[0];
801}
802
803void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
804    mSnapshot->transform->copyTo(*matrix);
805}
806
807void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
808    SkMatrix transform;
809    mSnapshot->transform->copyTo(transform);
810    transform.preConcat(*matrix);
811    mSnapshot->transform->load(transform);
812}
813
814///////////////////////////////////////////////////////////////////////////////
815// Clipping
816///////////////////////////////////////////////////////////////////////////////
817
818void OpenGLRenderer::setScissorFromClip() {
819    Rect clip(*mSnapshot->clipRect);
820    clip.snapToPixelBoundaries();
821    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
822    mDirtyClip = false;
823}
824
825const Rect& OpenGLRenderer::getClipBounds() {
826    return mSnapshot->getLocalClip();
827}
828
829bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
830    if (mSnapshot->isIgnored()) {
831        return true;
832    }
833
834    Rect r(left, top, right, bottom);
835    mSnapshot->transform->mapRect(r);
836    r.snapToPixelBoundaries();
837
838    Rect clipRect(*mSnapshot->clipRect);
839    clipRect.snapToPixelBoundaries();
840
841    return !clipRect.intersects(r);
842}
843
844bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
845    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
846    if (clipped) {
847        dirtyClip();
848    }
849    return !mSnapshot->clipRect->isEmpty();
850}
851
852///////////////////////////////////////////////////////////////////////////////
853// Drawing commands
854///////////////////////////////////////////////////////////////////////////////
855
856void OpenGLRenderer::setupDraw() {
857    if (mDirtyClip) {
858        setScissorFromClip();
859    }
860    mDescription.reset();
861    mSetShaderColor = false;
862    mColorSet = false;
863    mColorA = mColorR = mColorG = mColorB = 0.0f;
864    mTextureUnit = 0;
865    mTrackDirtyRegions = true;
866    mTexCoordsSlot = -1;
867}
868
869void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
870    mDescription.hasTexture = true;
871    mDescription.hasAlpha8Texture = isAlpha8;
872}
873
874void OpenGLRenderer::setupDrawColor(int color) {
875    setupDrawColor(color, (color >> 24) & 0xFF);
876}
877
878void OpenGLRenderer::setupDrawColor(int color, int alpha) {
879    mColorA = alpha / 255.0f;
880    const float a = mColorA / 255.0f;
881    mColorR = a * ((color >> 16) & 0xFF);
882    mColorG = a * ((color >>  8) & 0xFF);
883    mColorB = a * ((color      ) & 0xFF);
884    mColorSet = true;
885    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
886}
887
888void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
889    mColorA = alpha / 255.0f;
890    const float a = mColorA / 255.0f;
891    mColorR = a * ((color >> 16) & 0xFF);
892    mColorG = a * ((color >>  8) & 0xFF);
893    mColorB = a * ((color      ) & 0xFF);
894    mColorSet = true;
895    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
896}
897
898void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
899    mColorA = a;
900    mColorR = r;
901    mColorG = g;
902    mColorB = b;
903    mColorSet = true;
904    mSetShaderColor = mDescription.setColor(r, g, b, a);
905}
906
907void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
908    mColorA = a;
909    mColorR = r;
910    mColorG = g;
911    mColorB = b;
912    mColorSet = true;
913    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
914}
915
916void OpenGLRenderer::setupDrawShader() {
917    if (mShader) {
918        mShader->describe(mDescription, mCaches.extensions);
919    }
920}
921
922void OpenGLRenderer::setupDrawColorFilter() {
923    if (mColorFilter) {
924        mColorFilter->describe(mDescription, mCaches.extensions);
925    }
926}
927
928void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
929    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
930            mDescription, swapSrcDst);
931}
932
933void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
934    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
935            mDescription, swapSrcDst);
936}
937
938void OpenGLRenderer::setupDrawProgram() {
939    useProgram(mCaches.programCache.get(mDescription));
940}
941
942void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
943    mTrackDirtyRegions = false;
944}
945
946void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
947        bool ignoreTransform) {
948    mModelView.loadTranslate(left, top, 0.0f);
949    if (!ignoreTransform) {
950        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
951        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
952    } else {
953        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
954        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
955    }
956}
957
958void OpenGLRenderer::setupDrawModelViewIdentity() {
959    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
960}
961
962void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
963        bool ignoreTransform, bool ignoreModelView) {
964    if (!ignoreModelView) {
965        mModelView.loadTranslate(left, top, 0.0f);
966        mModelView.scale(right - left, bottom - top, 1.0f);
967    } else {
968        mModelView.loadIdentity();
969    }
970    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
971    if (!ignoreTransform) {
972        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
973        if (mTrackDirtyRegions && dirty) {
974            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
975        }
976    } else {
977        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
978        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
979    }
980}
981
982void OpenGLRenderer::setupDrawColorUniforms() {
983    if (mColorSet || (mShader && mSetShaderColor)) {
984        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
985    }
986}
987
988void OpenGLRenderer::setupDrawPureColorUniforms() {
989    if (mSetShaderColor) {
990        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
991    }
992}
993
994void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
995    if (mShader) {
996        if (ignoreTransform) {
997            mModelView.loadInverse(*mSnapshot->transform);
998        }
999        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
1000    }
1001}
1002
1003void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1004    if (mShader) {
1005        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1006    }
1007}
1008
1009void OpenGLRenderer::setupDrawColorFilterUniforms() {
1010    if (mColorFilter) {
1011        mColorFilter->setupProgram(mCaches.currentProgram);
1012    }
1013}
1014
1015void OpenGLRenderer::setupDrawSimpleMesh() {
1016    mCaches.bindMeshBuffer();
1017    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1018            gMeshStride, 0);
1019}
1020
1021void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1022    bindTexture(texture);
1023    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1024
1025    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1026    glEnableVertexAttribArray(mTexCoordsSlot);
1027}
1028
1029void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1030    if (!vertices) {
1031        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1032    } else {
1033        mCaches.unbindMeshBuffer();
1034    }
1035    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1036            gMeshStride, vertices);
1037    if (mTexCoordsSlot >= 0) {
1038        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1039    }
1040}
1041
1042void OpenGLRenderer::finishDrawTexture() {
1043    glDisableVertexAttribArray(mTexCoordsSlot);
1044}
1045
1046///////////////////////////////////////////////////////////////////////////////
1047// Drawing
1048///////////////////////////////////////////////////////////////////////////////
1049
1050bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t width, uint32_t height,
1051        Rect& dirty, uint32_t level) {
1052    if (quickReject(0.0f, 0.0f, width, height)) {
1053        return false;
1054    }
1055
1056    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1057    // will be performed by the display list itself
1058    if (displayList) {
1059        return displayList->replay(*this, dirty, level);
1060    }
1061
1062    return false;
1063}
1064
1065void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1066    const float right = left + bitmap->width();
1067    const float bottom = top + bitmap->height();
1068
1069    if (quickReject(left, top, right, bottom)) {
1070        return;
1071    }
1072
1073    glActiveTexture(gTextureUnits[0]);
1074    Texture* texture = mCaches.textureCache.get(bitmap);
1075    if (!texture) return;
1076    const AutoTexture autoCleanup(texture);
1077
1078    drawTextureRect(left, top, right, bottom, texture, paint);
1079}
1080
1081void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1082    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1083    const mat4 transform(*matrix);
1084    transform.mapRect(r);
1085
1086    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1087        return;
1088    }
1089
1090    glActiveTexture(gTextureUnits[0]);
1091    Texture* texture = mCaches.textureCache.get(bitmap);
1092    if (!texture) return;
1093    const AutoTexture autoCleanup(texture);
1094
1095    // This could be done in a cheaper way, all we need is pass the matrix
1096    // to the vertex shader. The save/restore is a bit overkill.
1097    save(SkCanvas::kMatrix_SaveFlag);
1098    concatMatrix(matrix);
1099    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1100    restore();
1101}
1102
1103void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1104        float* vertices, int* colors, SkPaint* paint) {
1105    // TODO: Do a quickReject
1106    if (!vertices || mSnapshot->isIgnored()) {
1107        return;
1108    }
1109
1110    glActiveTexture(gTextureUnits[0]);
1111    Texture* texture = mCaches.textureCache.get(bitmap);
1112    if (!texture) return;
1113    const AutoTexture autoCleanup(texture);
1114    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1115
1116    int alpha;
1117    SkXfermode::Mode mode;
1118    getAlphaAndMode(paint, &alpha, &mode);
1119
1120    const uint32_t count = meshWidth * meshHeight * 6;
1121
1122    float left = FLT_MAX;
1123    float top = FLT_MAX;
1124    float right = FLT_MIN;
1125    float bottom = FLT_MIN;
1126
1127#if RENDER_LAYERS_AS_REGIONS
1128    bool hasActiveLayer = hasLayer();
1129#else
1130    bool hasActiveLayer = false;
1131#endif
1132
1133    // TODO: Support the colors array
1134    TextureVertex mesh[count];
1135    TextureVertex* vertex = mesh;
1136    for (int32_t y = 0; y < meshHeight; y++) {
1137        for (int32_t x = 0; x < meshWidth; x++) {
1138            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1139
1140            float u1 = float(x) / meshWidth;
1141            float u2 = float(x + 1) / meshWidth;
1142            float v1 = float(y) / meshHeight;
1143            float v2 = float(y + 1) / meshHeight;
1144
1145            int ax = i + (meshWidth + 1) * 2;
1146            int ay = ax + 1;
1147            int bx = i;
1148            int by = bx + 1;
1149            int cx = i + 2;
1150            int cy = cx + 1;
1151            int dx = i + (meshWidth + 1) * 2 + 2;
1152            int dy = dx + 1;
1153
1154            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1155            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1156            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1157
1158            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1159            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1160            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1161
1162#if RENDER_LAYERS_AS_REGIONS
1163            if (hasActiveLayer) {
1164                // TODO: This could be optimized to avoid unnecessary ops
1165                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1166                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1167                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1168                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1169            }
1170#endif
1171        }
1172    }
1173
1174#if RENDER_LAYERS_AS_REGIONS
1175    if (hasActiveLayer) {
1176        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1177    }
1178#endif
1179
1180    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1181            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1182            GL_TRIANGLES, count, false, false, 0, false, false);
1183}
1184
1185void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1186         float srcLeft, float srcTop, float srcRight, float srcBottom,
1187         float dstLeft, float dstTop, float dstRight, float dstBottom,
1188         SkPaint* paint) {
1189    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1190        return;
1191    }
1192
1193    glActiveTexture(gTextureUnits[0]);
1194    Texture* texture = mCaches.textureCache.get(bitmap);
1195    if (!texture) return;
1196    const AutoTexture autoCleanup(texture);
1197    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1198
1199    const float width = texture->width;
1200    const float height = texture->height;
1201
1202    const float u1 = srcLeft / width;
1203    const float v1 = srcTop / height;
1204    const float u2 = srcRight / width;
1205    const float v2 = srcBottom / height;
1206
1207    mCaches.unbindMeshBuffer();
1208    resetDrawTextureTexCoords(u1, v1, u2, v2);
1209
1210    int alpha;
1211    SkXfermode::Mode mode;
1212    getAlphaAndMode(paint, &alpha, &mode);
1213
1214    if (mSnapshot->transform->isPureTranslate()) {
1215        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1216        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1217
1218        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1219                texture->id, alpha / 255.0f, mode, texture->blend,
1220                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1221                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1222    } else {
1223        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1224                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1225                GL_TRIANGLE_STRIP, gMeshCount);
1226    }
1227
1228    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1229}
1230
1231void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1232        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1233        float left, float top, float right, float bottom, SkPaint* paint) {
1234    if (quickReject(left, top, right, bottom)) {
1235        return;
1236    }
1237
1238    glActiveTexture(gTextureUnits[0]);
1239    Texture* texture = mCaches.textureCache.get(bitmap);
1240    if (!texture) return;
1241    const AutoTexture autoCleanup(texture);
1242    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1243
1244    int alpha;
1245    SkXfermode::Mode mode;
1246    getAlphaAndMode(paint, &alpha, &mode);
1247
1248    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1249            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1250
1251    if (mesh && mesh->verticesCount > 0) {
1252        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1253#if RENDER_LAYERS_AS_REGIONS
1254        // Mark the current layer dirty where we are going to draw the patch
1255        if (hasLayer() && mesh->hasEmptyQuads) {
1256            const float offsetX = left + mSnapshot->transform->getTranslateX();
1257            const float offsetY = top + mSnapshot->transform->getTranslateY();
1258            const size_t count = mesh->quads.size();
1259            for (size_t i = 0; i < count; i++) {
1260                const Rect& bounds = mesh->quads.itemAt(i);
1261                if (pureTranslate) {
1262                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1263                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1264                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1265                } else {
1266                    dirtyLayer(left + bounds.left, top + bounds.top,
1267                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1268                }
1269            }
1270        }
1271#endif
1272
1273        if (pureTranslate) {
1274            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1275            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1276
1277            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1278                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1279                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1280                    true, !mesh->hasEmptyQuads);
1281        } else {
1282            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1283                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1284                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1285                    true, !mesh->hasEmptyQuads);
1286        }
1287    }
1288}
1289
1290void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1291    if (mSnapshot->isIgnored()) return;
1292
1293    const bool isAA = paint->isAntiAlias();
1294    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1295    // A stroke width of 0 has a special meaningin Skia:
1296    // it draws an unscaled 1px wide line
1297    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1298
1299    int alpha;
1300    SkXfermode::Mode mode;
1301    getAlphaAndMode(paint, &alpha, &mode);
1302
1303    int verticesCount = count >> 2;
1304    int generatedVerticesCount = 0;
1305    if (!isHairLine) {
1306        // TODO: AA needs more vertices
1307        verticesCount *= 6;
1308    } else {
1309        // TODO: AA will be different
1310        verticesCount *= 2;
1311    }
1312
1313    TextureVertex lines[verticesCount];
1314    TextureVertex* vertex = &lines[0];
1315
1316    setupDraw();
1317    setupDrawColor(paint->getColor(), alpha);
1318    setupDrawColorFilter();
1319    setupDrawShader();
1320    setupDrawBlending(mode);
1321    setupDrawProgram();
1322    setupDrawModelViewIdentity();
1323    setupDrawColorUniforms();
1324    setupDrawColorFilterUniforms();
1325    setupDrawShaderIdentityUniforms();
1326    setupDrawMesh(vertex);
1327
1328    if (!isHairLine) {
1329        // TODO: Handle the AA case
1330        for (int i = 0; i < count; i += 4) {
1331            // a = start point, b = end point
1332            vec2 a(points[i], points[i + 1]);
1333            vec2 b(points[i + 2], points[i + 3]);
1334
1335            // Bias to snap to the same pixels as Skia
1336            a += 0.375;
1337            b += 0.375;
1338
1339            // Find the normal to the line
1340            vec2 n = (b - a).copyNormalized() * strokeWidth;
1341            float x = n.x;
1342            n.x = -n.y;
1343            n.y = x;
1344
1345            // Four corners of the rectangle defining a thick line
1346            vec2 p1 = a - n;
1347            vec2 p2 = a + n;
1348            vec2 p3 = b + n;
1349            vec2 p4 = b - n;
1350
1351            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1352            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1353            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1354            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1355
1356            if (!quickReject(left, top, right, bottom)) {
1357                // Draw the line as 2 triangles, could be optimized
1358                // by using only 4 vertices and the correct indices
1359                // Also we should probably used non textured vertices
1360                // when line AA is disabled to save on bandwidth
1361                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1362                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1363                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1364                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1365                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1366                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1367
1368                generatedVerticesCount += 6;
1369
1370                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1371            }
1372        }
1373
1374        if (generatedVerticesCount > 0) {
1375            // GL_LINE does not give the result we want to match Skia
1376            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1377        }
1378    } else {
1379        // TODO: Handle the AA case
1380        for (int i = 0; i < count; i += 4) {
1381            const float left = fmin(points[i], points[i + 1]);
1382            const float right = fmax(points[i], points[i + 1]);
1383            const float top = fmin(points[i + 2], points[i + 3]);
1384            const float bottom = fmax(points[i + 2], points[i + 3]);
1385
1386            if (!quickReject(left, top, right, bottom)) {
1387                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1388                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1389
1390                generatedVerticesCount += 2;
1391
1392                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1393            }
1394        }
1395
1396        if (generatedVerticesCount > 0) {
1397            glLineWidth(1.0f);
1398            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1399        }
1400    }
1401}
1402
1403void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1404    // No need to check against the clip, we fill the clip region
1405    if (mSnapshot->isIgnored()) return;
1406
1407    Rect& clip(*mSnapshot->clipRect);
1408    clip.snapToPixelBoundaries();
1409
1410    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1411}
1412
1413void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1414    if (!texture) return;
1415    const AutoTexture autoCleanup(texture);
1416
1417    const float x = left + texture->left - texture->offset;
1418    const float y = top + texture->top - texture->offset;
1419
1420    drawPathTexture(texture, x, y, paint);
1421}
1422
1423void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1424        float rx, float ry, SkPaint* paint) {
1425    if (mSnapshot->isIgnored()) return;
1426
1427    glActiveTexture(gTextureUnits[0]);
1428    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1429            right - left, bottom - top, rx, ry, paint);
1430    drawShape(left, top, texture, paint);
1431}
1432
1433void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1434    if (mSnapshot->isIgnored()) return;
1435
1436    glActiveTexture(gTextureUnits[0]);
1437    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1438    drawShape(x - radius, y - radius, texture, paint);
1439}
1440
1441void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1442    if (mSnapshot->isIgnored()) return;
1443
1444    glActiveTexture(gTextureUnits[0]);
1445    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1446    drawShape(left, top, texture, paint);
1447}
1448
1449void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1450        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1451    if (mSnapshot->isIgnored()) return;
1452
1453    if (fabs(sweepAngle) >= 360.0f) {
1454        drawOval(left, top, right, bottom, paint);
1455        return;
1456    }
1457
1458    glActiveTexture(gTextureUnits[0]);
1459    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1460            startAngle, sweepAngle, useCenter, paint);
1461    drawShape(left, top, texture, paint);
1462}
1463
1464void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1465        SkPaint* paint) {
1466    if (mSnapshot->isIgnored()) return;
1467
1468    glActiveTexture(gTextureUnits[0]);
1469    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1470    drawShape(left, top, texture, paint);
1471}
1472
1473void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1474    if (p->getStyle() != SkPaint::kFill_Style) {
1475        drawRectAsShape(left, top, right, bottom, p);
1476        return;
1477    }
1478
1479    if (quickReject(left, top, right, bottom)) {
1480        return;
1481    }
1482
1483    SkXfermode::Mode mode;
1484    if (!mCaches.extensions.hasFramebufferFetch()) {
1485        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1486        if (!isMode) {
1487            // Assume SRC_OVER
1488            mode = SkXfermode::kSrcOver_Mode;
1489        }
1490    } else {
1491        mode = getXfermode(p->getXfermode());
1492    }
1493
1494    int color = p->getColor();
1495    drawColorRect(left, top, right, bottom, color, mode);
1496}
1497
1498void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1499        float x, float y, SkPaint* paint) {
1500    if (text == NULL || count == 0) {
1501        return;
1502    }
1503    if (mSnapshot->isIgnored()) return;
1504
1505    paint->setAntiAlias(true);
1506
1507    float length = -1.0f;
1508    switch (paint->getTextAlign()) {
1509        case SkPaint::kCenter_Align:
1510            length = paint->measureText(text, bytesCount);
1511            x -= length / 2.0f;
1512            break;
1513        case SkPaint::kRight_Align:
1514            length = paint->measureText(text, bytesCount);
1515            x -= length;
1516            break;
1517        default:
1518            break;
1519    }
1520
1521    const float oldX = x;
1522    const float oldY = y;
1523    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1524    if (pureTranslate) {
1525        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1526        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1527    }
1528
1529    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1530    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1531            paint->getTextSize());
1532
1533    int alpha;
1534    SkXfermode::Mode mode;
1535    getAlphaAndMode(paint, &alpha, &mode);
1536
1537    if (mHasShadow) {
1538        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1539        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1540                count, mShadowRadius);
1541        const AutoTexture autoCleanup(shadow);
1542
1543        const float sx = x - shadow->left + mShadowDx;
1544        const float sy = y - shadow->top + mShadowDy;
1545
1546        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1547
1548        glActiveTexture(gTextureUnits[0]);
1549        setupDraw();
1550        setupDrawWithTexture(true);
1551        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1552        setupDrawBlending(true, mode);
1553        setupDrawProgram();
1554        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1555        setupDrawTexture(shadow->id);
1556        setupDrawPureColorUniforms();
1557        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1558
1559        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1560        finishDrawTexture();
1561    }
1562
1563    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1564        return;
1565    }
1566
1567    // Pick the appropriate texture filtering
1568    bool linearFilter = mSnapshot->transform->changesBounds();
1569    if (pureTranslate && !linearFilter) {
1570        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1571    }
1572
1573    glActiveTexture(gTextureUnits[0]);
1574    setupDraw();
1575    setupDrawDirtyRegionsDisabled();
1576    setupDrawWithTexture(true);
1577    setupDrawAlpha8Color(paint->getColor(), alpha);
1578    setupDrawColorFilter();
1579    setupDrawShader();
1580    setupDrawBlending(true, mode);
1581    setupDrawProgram();
1582    setupDrawModelView(x, y, x, y, pureTranslate, true);
1583    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1584    setupDrawPureColorUniforms();
1585    setupDrawColorFilterUniforms();
1586    setupDrawShaderUniforms(pureTranslate);
1587
1588    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1589    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1590
1591#if RENDER_LAYERS_AS_REGIONS
1592    bool hasActiveLayer = hasLayer();
1593#else
1594    bool hasActiveLayer = false;
1595#endif
1596    mCaches.unbindMeshBuffer();
1597
1598    // Tell font renderer the locations of position and texture coord
1599    // attributes so it can bind its data properly
1600    int positionSlot = mCaches.currentProgram->position;
1601    fontRenderer.setAttributeBindingSlots(positionSlot, mTexCoordsSlot);
1602    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1603            hasActiveLayer ? &bounds : NULL)) {
1604#if RENDER_LAYERS_AS_REGIONS
1605        if (hasActiveLayer) {
1606            if (!pureTranslate) {
1607                mSnapshot->transform->mapRect(bounds);
1608            }
1609            dirtyLayerUnchecked(bounds, getRegion());
1610        }
1611#endif
1612    }
1613
1614    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1615    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1616
1617    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1618}
1619
1620void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1621    if (mSnapshot->isIgnored()) return;
1622
1623    glActiveTexture(gTextureUnits[0]);
1624
1625    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1626    if (!texture) return;
1627    const AutoTexture autoCleanup(texture);
1628
1629    const float x = texture->left - texture->offset;
1630    const float y = texture->top - texture->offset;
1631
1632    drawPathTexture(texture, x, y, paint);
1633}
1634
1635void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1636    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1637        return;
1638    }
1639
1640    glActiveTexture(gTextureUnits[0]);
1641
1642    int alpha;
1643    SkXfermode::Mode mode;
1644    getAlphaAndMode(paint, &alpha, &mode);
1645
1646    layer->alpha = alpha;
1647    layer->mode = mode;
1648
1649#if RENDER_LAYERS_AS_REGIONS
1650    if (!layer->region.isEmpty()) {
1651#if RENDER_LAYERS_RECT_AS_RECT
1652        if (layer->region.isRect()) {
1653            const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1654            composeLayerRect(layer, r);
1655        } else if (layer->mesh) {
1656#else
1657        if (layer->mesh) {
1658#endif
1659            const float a = alpha / 255.0f;
1660            const Rect& rect = layer->layer;
1661
1662            setupDraw();
1663            setupDrawWithTexture();
1664            setupDrawColor(a, a, a, a);
1665            setupDrawColorFilter();
1666            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1667            setupDrawProgram();
1668            setupDrawPureColorUniforms();
1669            setupDrawColorFilterUniforms();
1670            setupDrawTexture(layer->texture);
1671            // TODO: The current layer, if any, will be dirtied with the bounding box
1672            //       of the layer we are drawing. Since the layer we are drawing has
1673            //       a mesh, we know the dirty region, we should use it instead
1674            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1675            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1676
1677            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1678                    GL_UNSIGNED_SHORT, layer->meshIndices);
1679
1680            finishDrawTexture();
1681
1682#if DEBUG_LAYERS_AS_REGIONS
1683            drawRegionRects(layer->region);
1684#endif
1685        }
1686    }
1687#else
1688    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1689    composeLayerRect(layer, r);
1690#endif
1691}
1692
1693///////////////////////////////////////////////////////////////////////////////
1694// Shaders
1695///////////////////////////////////////////////////////////////////////////////
1696
1697void OpenGLRenderer::resetShader() {
1698    mShader = NULL;
1699}
1700
1701void OpenGLRenderer::setupShader(SkiaShader* shader) {
1702    mShader = shader;
1703    if (mShader) {
1704        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1705    }
1706}
1707
1708///////////////////////////////////////////////////////////////////////////////
1709// Color filters
1710///////////////////////////////////////////////////////////////////////////////
1711
1712void OpenGLRenderer::resetColorFilter() {
1713    mColorFilter = NULL;
1714}
1715
1716void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1717    mColorFilter = filter;
1718}
1719
1720///////////////////////////////////////////////////////////////////////////////
1721// Drop shadow
1722///////////////////////////////////////////////////////////////////////////////
1723
1724void OpenGLRenderer::resetShadow() {
1725    mHasShadow = false;
1726}
1727
1728void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1729    mHasShadow = true;
1730    mShadowRadius = radius;
1731    mShadowDx = dx;
1732    mShadowDy = dy;
1733    mShadowColor = color;
1734}
1735
1736///////////////////////////////////////////////////////////////////////////////
1737// Drawing implementation
1738///////////////////////////////////////////////////////////////////////////////
1739
1740void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1741        float x, float y, SkPaint* paint) {
1742    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1743        return;
1744    }
1745
1746    int alpha;
1747    SkXfermode::Mode mode;
1748    getAlphaAndMode(paint, &alpha, &mode);
1749
1750    setupDraw();
1751    setupDrawWithTexture(true);
1752    setupDrawAlpha8Color(paint->getColor(), alpha);
1753    setupDrawColorFilter();
1754    setupDrawShader();
1755    setupDrawBlending(true, mode);
1756    setupDrawProgram();
1757    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1758    setupDrawTexture(texture->id);
1759    setupDrawPureColorUniforms();
1760    setupDrawColorFilterUniforms();
1761    setupDrawShaderUniforms();
1762    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1763
1764    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1765
1766    finishDrawTexture();
1767}
1768
1769// Same values used by Skia
1770#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1771#define kStdUnderline_Offset    (1.0f / 9.0f)
1772#define kStdUnderline_Thickness (1.0f / 18.0f)
1773
1774void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1775        float x, float y, SkPaint* paint) {
1776    // Handle underline and strike-through
1777    uint32_t flags = paint->getFlags();
1778    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1779        float underlineWidth = length;
1780        // If length is > 0.0f, we already measured the text for the text alignment
1781        if (length <= 0.0f) {
1782            underlineWidth = paint->measureText(text, bytesCount);
1783        }
1784
1785        float offsetX = 0;
1786        switch (paint->getTextAlign()) {
1787            case SkPaint::kCenter_Align:
1788                offsetX = underlineWidth * 0.5f;
1789                break;
1790            case SkPaint::kRight_Align:
1791                offsetX = underlineWidth;
1792                break;
1793            default:
1794                break;
1795        }
1796
1797        if (underlineWidth > 0.0f) {
1798            const float textSize = paint->getTextSize();
1799            // TODO: Support stroke width < 1.0f when we have AA lines
1800            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
1801
1802            const float left = x - offsetX;
1803            float top = 0.0f;
1804
1805            int linesCount = 0;
1806            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
1807            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
1808
1809            const int pointsCount = 4 * linesCount;
1810            float points[pointsCount];
1811            int currentPoint = 0;
1812
1813            if (flags & SkPaint::kUnderlineText_Flag) {
1814                top = y + textSize * kStdUnderline_Offset;
1815                points[currentPoint++] = left;
1816                points[currentPoint++] = top;
1817                points[currentPoint++] = left + underlineWidth;
1818                points[currentPoint++] = top;
1819            }
1820
1821            if (flags & SkPaint::kStrikeThruText_Flag) {
1822                top = y + textSize * kStdStrikeThru_Offset;
1823                points[currentPoint++] = left;
1824                points[currentPoint++] = top;
1825                points[currentPoint++] = left + underlineWidth;
1826                points[currentPoint++] = top;
1827            }
1828
1829            SkPaint linesPaint(*paint);
1830            linesPaint.setStrokeWidth(strokeWidth);
1831
1832            drawLines(&points[0], pointsCount, &linesPaint);
1833        }
1834    }
1835}
1836
1837void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1838        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1839    // If a shader is set, preserve only the alpha
1840    if (mShader) {
1841        color |= 0x00ffffff;
1842    }
1843
1844    setupDraw();
1845    setupDrawColor(color);
1846    setupDrawShader();
1847    setupDrawColorFilter();
1848    setupDrawBlending(mode);
1849    setupDrawProgram();
1850    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1851    setupDrawColorUniforms();
1852    setupDrawShaderUniforms(ignoreTransform);
1853    setupDrawColorFilterUniforms();
1854    setupDrawSimpleMesh();
1855
1856    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1857}
1858
1859void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1860        Texture* texture, SkPaint* paint) {
1861    int alpha;
1862    SkXfermode::Mode mode;
1863    getAlphaAndMode(paint, &alpha, &mode);
1864
1865    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1866
1867    if (mSnapshot->transform->isPureTranslate()) {
1868        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1869        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1870
1871        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1872                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1873                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1874    } else {
1875        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1876                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1877                GL_TRIANGLE_STRIP, gMeshCount);
1878    }
1879}
1880
1881void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1882        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1883    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1884            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1885}
1886
1887void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1888        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1889        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1890        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1891
1892    setupDraw();
1893    setupDrawWithTexture();
1894    setupDrawColor(alpha, alpha, alpha, alpha);
1895    setupDrawColorFilter();
1896    setupDrawBlending(blend, mode, swapSrcDst);
1897    setupDrawProgram();
1898    if (!dirty) {
1899        setupDrawDirtyRegionsDisabled();
1900    }
1901    if (!ignoreScale) {
1902        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1903    } else {
1904        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1905    }
1906    setupDrawPureColorUniforms();
1907    setupDrawColorFilterUniforms();
1908    setupDrawTexture(texture);
1909    setupDrawMesh(vertices, texCoords, vbo);
1910
1911    glDrawArrays(drawMode, 0, elementsCount);
1912
1913    finishDrawTexture();
1914}
1915
1916void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1917        ProgramDescription& description, bool swapSrcDst) {
1918    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1919    if (blend) {
1920        if (mode < SkXfermode::kPlus_Mode) {
1921            if (!mCaches.blend) {
1922                glEnable(GL_BLEND);
1923            }
1924
1925            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1926            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1927
1928            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1929                glBlendFunc(sourceMode, destMode);
1930                mCaches.lastSrcMode = sourceMode;
1931                mCaches.lastDstMode = destMode;
1932            }
1933        } else {
1934            // These blend modes are not supported by OpenGL directly and have
1935            // to be implemented using shaders. Since the shader will perform
1936            // the blending, turn blending off here
1937            if (mCaches.extensions.hasFramebufferFetch()) {
1938                description.framebufferMode = mode;
1939                description.swapSrcDst = swapSrcDst;
1940            }
1941
1942            if (mCaches.blend) {
1943                glDisable(GL_BLEND);
1944            }
1945            blend = false;
1946        }
1947    } else if (mCaches.blend) {
1948        glDisable(GL_BLEND);
1949    }
1950    mCaches.blend = blend;
1951}
1952
1953bool OpenGLRenderer::useProgram(Program* program) {
1954    if (!program->isInUse()) {
1955        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1956        program->use();
1957        mCaches.currentProgram = program;
1958        return false;
1959    }
1960    return true;
1961}
1962
1963void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1964    TextureVertex* v = &mMeshVertices[0];
1965    TextureVertex::setUV(v++, u1, v1);
1966    TextureVertex::setUV(v++, u2, v1);
1967    TextureVertex::setUV(v++, u1, v2);
1968    TextureVertex::setUV(v++, u2, v2);
1969}
1970
1971void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1972    if (paint) {
1973        if (!mCaches.extensions.hasFramebufferFetch()) {
1974            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1975            if (!isMode) {
1976                // Assume SRC_OVER
1977                *mode = SkXfermode::kSrcOver_Mode;
1978            }
1979        } else {
1980            *mode = getXfermode(paint->getXfermode());
1981        }
1982
1983        // Skia draws using the color's alpha channel if < 255
1984        // Otherwise, it uses the paint's alpha
1985        int color = paint->getColor();
1986        *alpha = (color >> 24) & 0xFF;
1987        if (*alpha == 255) {
1988            *alpha = paint->getAlpha();
1989        }
1990    } else {
1991        *mode = SkXfermode::kSrcOver_Mode;
1992        *alpha = 255;
1993    }
1994}
1995
1996SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1997    // In the future we should look at unifying the Porter-Duff modes and
1998    // SkXferModes so that we can use SkXfermode::IsMode(xfer, &mode).
1999    if (mode == NULL) {
2000        return SkXfermode::kSrcOver_Mode;
2001    }
2002    return mode->fMode;
2003}
2004
2005void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
2006    bool bound = false;
2007    if (wrapS != texture->wrapS) {
2008        glBindTexture(GL_TEXTURE_2D, texture->id);
2009        bound = true;
2010        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
2011        texture->wrapS = wrapS;
2012    }
2013    if (wrapT != texture->wrapT) {
2014        if (!bound) {
2015            glBindTexture(GL_TEXTURE_2D, texture->id);
2016        }
2017        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
2018        texture->wrapT = wrapT;
2019    }
2020}
2021
2022}; // namespace uirenderer
2023}; // namespace android
2024