OpenGLRenderer.cpp revision ad37cd3b5d3de9dd0858af04fbccd102e8ff4b0e 
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 (layer->region.isRect()) {
640        composeLayerRect(layer, rect);
641        layer->region.clear();
642        return;
643    }
644
645    if (!layer->region.isEmpty()) {
646        size_t count;
647        const android::Rect* rects = layer->region.getArray(&count);
648
649        const float alpha = layer->alpha / 255.0f;
650        const float texX = 1.0f / float(layer->width);
651        const float texY = 1.0f / float(layer->height);
652        const float height = rect.getHeight();
653
654        TextureVertex* mesh = mCaches.getRegionMesh();
655        GLsizei numQuads = 0;
656
657        setupDraw();
658        setupDrawWithTexture();
659        setupDrawColor(alpha, alpha, alpha, alpha);
660        setupDrawColorFilter();
661        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
662        setupDrawProgram();
663        setupDrawDirtyRegionsDisabled();
664        setupDrawPureColorUniforms();
665        setupDrawColorFilterUniforms();
666        setupDrawTexture(layer->texture);
667        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
668        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
669
670        for (size_t i = 0; i < count; i++) {
671            const android::Rect* r = &rects[i];
672
673            const float u1 = r->left * texX;
674            const float v1 = (height - r->top) * texY;
675            const float u2 = r->right * texX;
676            const float v2 = (height - r->bottom) * texY;
677
678            // TODO: Reject quads outside of the clip
679            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
680            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
681            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
682            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
683
684            numQuads++;
685
686            if (numQuads >= REGION_MESH_QUAD_COUNT) {
687                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
688                numQuads = 0;
689                mesh = mCaches.getRegionMesh();
690            }
691        }
692
693        if (numQuads > 0) {
694            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
695        }
696
697        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
698        finishDrawTexture();
699
700#if DEBUG_LAYERS_AS_REGIONS
701        drawRegionRects(layer->region);
702#endif
703
704        layer->region.clear();
705    }
706#else
707    composeLayerRect(layer, rect);
708#endif
709}
710
711void OpenGLRenderer::drawRegionRects(const Region& region) {
712#if DEBUG_LAYERS_AS_REGIONS
713    size_t count;
714    const android::Rect* rects = region.getArray(&count);
715
716    uint32_t colors[] = {
717            0x7fff0000, 0x7f00ff00,
718            0x7f0000ff, 0x7fff00ff,
719    };
720
721    int offset = 0;
722    int32_t top = rects[0].top;
723
724    for (size_t i = 0; i < count; i++) {
725        if (top != rects[i].top) {
726            offset ^= 0x2;
727            top = rects[i].top;
728        }
729
730        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
731        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
732                SkXfermode::kSrcOver_Mode);
733    }
734#endif
735}
736
737void OpenGLRenderer::dirtyLayer(const float left, const float top,
738        const float right, const float bottom, const mat4 transform) {
739#if RENDER_LAYERS_AS_REGIONS
740    if (hasLayer()) {
741        Rect bounds(left, top, right, bottom);
742        transform.mapRect(bounds);
743        dirtyLayerUnchecked(bounds, getRegion());
744    }
745#endif
746}
747
748void OpenGLRenderer::dirtyLayer(const float left, const float top,
749        const float right, const float bottom) {
750#if RENDER_LAYERS_AS_REGIONS
751    if (hasLayer()) {
752        Rect bounds(left, top, right, bottom);
753        dirtyLayerUnchecked(bounds, getRegion());
754    }
755#endif
756}
757
758void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
759#if RENDER_LAYERS_AS_REGIONS
760    if (bounds.intersect(*mSnapshot->clipRect)) {
761        bounds.snapToPixelBoundaries();
762        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
763        if (!dirty.isEmpty()) {
764            region->orSelf(dirty);
765        }
766    }
767#endif
768}
769
770///////////////////////////////////////////////////////////////////////////////
771// Transforms
772///////////////////////////////////////////////////////////////////////////////
773
774void OpenGLRenderer::translate(float dx, float dy) {
775    mSnapshot->transform->translate(dx, dy, 0.0f);
776}
777
778void OpenGLRenderer::rotate(float degrees) {
779    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
780}
781
782void OpenGLRenderer::scale(float sx, float sy) {
783    mSnapshot->transform->scale(sx, sy, 1.0f);
784}
785
786void OpenGLRenderer::skew(float sx, float sy) {
787    mSnapshot->transform->skew(sx, sy);
788}
789
790void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
791    mSnapshot->transform->load(*matrix);
792}
793
794const float* OpenGLRenderer::getMatrix() const {
795    if (mSnapshot->fbo != 0) {
796        return &mSnapshot->transform->data[0];
797    }
798    return &mIdentity.data[0];
799}
800
801void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
802    mSnapshot->transform->copyTo(*matrix);
803}
804
805void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
806    SkMatrix transform;
807    mSnapshot->transform->copyTo(transform);
808    transform.preConcat(*matrix);
809    mSnapshot->transform->load(transform);
810}
811
812///////////////////////////////////////////////////////////////////////////////
813// Clipping
814///////////////////////////////////////////////////////////////////////////////
815
816void OpenGLRenderer::setScissorFromClip() {
817    Rect clip(*mSnapshot->clipRect);
818    clip.snapToPixelBoundaries();
819    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
820    mDirtyClip = false;
821}
822
823const Rect& OpenGLRenderer::getClipBounds() {
824    return mSnapshot->getLocalClip();
825}
826
827bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
828    if (mSnapshot->isIgnored()) {
829        return true;
830    }
831
832    Rect r(left, top, right, bottom);
833    mSnapshot->transform->mapRect(r);
834    r.snapToPixelBoundaries();
835
836    Rect clipRect(*mSnapshot->clipRect);
837    clipRect.snapToPixelBoundaries();
838
839    return !clipRect.intersects(r);
840}
841
842bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
843    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
844    if (clipped) {
845        dirtyClip();
846    }
847    return !mSnapshot->clipRect->isEmpty();
848}
849
850///////////////////////////////////////////////////////////////////////////////
851// Drawing commands
852///////////////////////////////////////////////////////////////////////////////
853
854void OpenGLRenderer::setupDraw() {
855    if (mDirtyClip) {
856        setScissorFromClip();
857    }
858    mDescription.reset();
859    mSetShaderColor = false;
860    mColorSet = false;
861    mColorA = mColorR = mColorG = mColorB = 0.0f;
862    mTextureUnit = 0;
863    mTrackDirtyRegions = true;
864    mTexCoordsSlot = -1;
865}
866
867void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
868    mDescription.hasTexture = true;
869    mDescription.hasAlpha8Texture = isAlpha8;
870}
871
872void OpenGLRenderer::setupDrawColor(int color) {
873    setupDrawColor(color, (color >> 24) & 0xFF);
874}
875
876void OpenGLRenderer::setupDrawColor(int color, int alpha) {
877    mColorA = alpha / 255.0f;
878    const float a = mColorA / 255.0f;
879    mColorR = a * ((color >> 16) & 0xFF);
880    mColorG = a * ((color >>  8) & 0xFF);
881    mColorB = a * ((color      ) & 0xFF);
882    mColorSet = true;
883    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
884}
885
886void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
887    mColorA = alpha / 255.0f;
888    const float a = mColorA / 255.0f;
889    mColorR = a * ((color >> 16) & 0xFF);
890    mColorG = a * ((color >>  8) & 0xFF);
891    mColorB = a * ((color      ) & 0xFF);
892    mColorSet = true;
893    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
894}
895
896void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
897    mColorA = a;
898    mColorR = r;
899    mColorG = g;
900    mColorB = b;
901    mColorSet = true;
902    mSetShaderColor = mDescription.setColor(r, g, b, a);
903}
904
905void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
906    mColorA = a;
907    mColorR = r;
908    mColorG = g;
909    mColorB = b;
910    mColorSet = true;
911    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
912}
913
914void OpenGLRenderer::setupDrawShader() {
915    if (mShader) {
916        mShader->describe(mDescription, mCaches.extensions);
917    }
918}
919
920void OpenGLRenderer::setupDrawColorFilter() {
921    if (mColorFilter) {
922        mColorFilter->describe(mDescription, mCaches.extensions);
923    }
924}
925
926void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
927    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
928            mDescription, swapSrcDst);
929}
930
931void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
932    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
933            mDescription, swapSrcDst);
934}
935
936void OpenGLRenderer::setupDrawProgram() {
937    useProgram(mCaches.programCache.get(mDescription));
938}
939
940void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
941    mTrackDirtyRegions = false;
942}
943
944void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
945        bool ignoreTransform) {
946    mModelView.loadTranslate(left, top, 0.0f);
947    if (!ignoreTransform) {
948        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
949        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
950    } else {
951        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
952        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
953    }
954}
955
956void OpenGLRenderer::setupDrawModelViewIdentity() {
957    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
958}
959
960void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
961        bool ignoreTransform, bool ignoreModelView) {
962    if (!ignoreModelView) {
963        mModelView.loadTranslate(left, top, 0.0f);
964        mModelView.scale(right - left, bottom - top, 1.0f);
965    } else {
966        mModelView.loadIdentity();
967    }
968    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
969    if (!ignoreTransform) {
970        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
971        if (mTrackDirtyRegions && dirty) {
972            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
973        }
974    } else {
975        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
976        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
977    }
978}
979
980void OpenGLRenderer::setupDrawColorUniforms() {
981    if (mColorSet || (mShader && mSetShaderColor)) {
982        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
983    }
984}
985
986void OpenGLRenderer::setupDrawPureColorUniforms() {
987    if (mSetShaderColor) {
988        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
989    }
990}
991
992void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
993    if (mShader) {
994        if (ignoreTransform) {
995            mModelView.loadInverse(*mSnapshot->transform);
996        }
997        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
998    }
999}
1000
1001void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1002    if (mShader) {
1003        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1004    }
1005}
1006
1007void OpenGLRenderer::setupDrawColorFilterUniforms() {
1008    if (mColorFilter) {
1009        mColorFilter->setupProgram(mCaches.currentProgram);
1010    }
1011}
1012
1013void OpenGLRenderer::setupDrawSimpleMesh() {
1014    mCaches.bindMeshBuffer();
1015    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1016            gMeshStride, 0);
1017}
1018
1019void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1020    bindTexture(texture);
1021    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1022
1023    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1024    glEnableVertexAttribArray(mTexCoordsSlot);
1025}
1026
1027void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1028    if (!vertices) {
1029        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1030    } else {
1031        mCaches.unbindMeshBuffer();
1032    }
1033    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1034            gMeshStride, vertices);
1035    if (mTexCoordsSlot >= 0) {
1036        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1037    }
1038}
1039
1040void OpenGLRenderer::finishDrawTexture() {
1041    glDisableVertexAttribArray(mTexCoordsSlot);
1042}
1043
1044///////////////////////////////////////////////////////////////////////////////
1045// Drawing
1046///////////////////////////////////////////////////////////////////////////////
1047
1048bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t width, uint32_t height,
1049        Rect& dirty, uint32_t level) {
1050    if (quickReject(0.0f, 0.0f, width, height)) {
1051        return false;
1052    }
1053
1054    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1055    // will be performed by the display list itself
1056    if (displayList) {
1057        return displayList->replay(*this, dirty, level);
1058    }
1059
1060    return false;
1061}
1062
1063void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1064    const float right = left + bitmap->width();
1065    const float bottom = top + bitmap->height();
1066
1067    if (quickReject(left, top, right, bottom)) {
1068        return;
1069    }
1070
1071    glActiveTexture(gTextureUnits[0]);
1072    Texture* texture = mCaches.textureCache.get(bitmap);
1073    if (!texture) return;
1074    const AutoTexture autoCleanup(texture);
1075
1076    drawTextureRect(left, top, right, bottom, texture, paint);
1077}
1078
1079void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1080    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1081    const mat4 transform(*matrix);
1082    transform.mapRect(r);
1083
1084    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1085        return;
1086    }
1087
1088    glActiveTexture(gTextureUnits[0]);
1089    Texture* texture = mCaches.textureCache.get(bitmap);
1090    if (!texture) return;
1091    const AutoTexture autoCleanup(texture);
1092
1093    // This could be done in a cheaper way, all we need is pass the matrix
1094    // to the vertex shader. The save/restore is a bit overkill.
1095    save(SkCanvas::kMatrix_SaveFlag);
1096    concatMatrix(matrix);
1097    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1098    restore();
1099}
1100
1101void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1102        float* vertices, int* colors, SkPaint* paint) {
1103    // TODO: Do a quickReject
1104    if (!vertices || mSnapshot->isIgnored()) {
1105        return;
1106    }
1107
1108    glActiveTexture(gTextureUnits[0]);
1109    Texture* texture = mCaches.textureCache.get(bitmap);
1110    if (!texture) return;
1111    const AutoTexture autoCleanup(texture);
1112    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1113
1114    int alpha;
1115    SkXfermode::Mode mode;
1116    getAlphaAndMode(paint, &alpha, &mode);
1117
1118    const uint32_t count = meshWidth * meshHeight * 6;
1119
1120    float left = FLT_MAX;
1121    float top = FLT_MAX;
1122    float right = FLT_MIN;
1123    float bottom = FLT_MIN;
1124
1125#if RENDER_LAYERS_AS_REGIONS
1126    bool hasActiveLayer = hasLayer();
1127#else
1128    bool hasActiveLayer = false;
1129#endif
1130
1131    // TODO: Support the colors array
1132    TextureVertex mesh[count];
1133    TextureVertex* vertex = mesh;
1134    for (int32_t y = 0; y < meshHeight; y++) {
1135        for (int32_t x = 0; x < meshWidth; x++) {
1136            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1137
1138            float u1 = float(x) / meshWidth;
1139            float u2 = float(x + 1) / meshWidth;
1140            float v1 = float(y) / meshHeight;
1141            float v2 = float(y + 1) / meshHeight;
1142
1143            int ax = i + (meshWidth + 1) * 2;
1144            int ay = ax + 1;
1145            int bx = i;
1146            int by = bx + 1;
1147            int cx = i + 2;
1148            int cy = cx + 1;
1149            int dx = i + (meshWidth + 1) * 2 + 2;
1150            int dy = dx + 1;
1151
1152            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1153            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1154            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1155
1156            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1157            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1158            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1159
1160#if RENDER_LAYERS_AS_REGIONS
1161            if (hasActiveLayer) {
1162                // TODO: This could be optimized to avoid unnecessary ops
1163                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1164                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1165                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1166                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1167            }
1168#endif
1169        }
1170    }
1171
1172#if RENDER_LAYERS_AS_REGIONS
1173    if (hasActiveLayer) {
1174        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1175    }
1176#endif
1177
1178    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1179            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1180            GL_TRIANGLES, count, false, false, 0, false, false);
1181}
1182
1183void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1184         float srcLeft, float srcTop, float srcRight, float srcBottom,
1185         float dstLeft, float dstTop, float dstRight, float dstBottom,
1186         SkPaint* paint) {
1187    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1188        return;
1189    }
1190
1191    glActiveTexture(gTextureUnits[0]);
1192    Texture* texture = mCaches.textureCache.get(bitmap);
1193    if (!texture) return;
1194    const AutoTexture autoCleanup(texture);
1195    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1196
1197    const float width = texture->width;
1198    const float height = texture->height;
1199
1200    const float u1 = srcLeft / width;
1201    const float v1 = srcTop / height;
1202    const float u2 = srcRight / width;
1203    const float v2 = srcBottom / height;
1204
1205    mCaches.unbindMeshBuffer();
1206    resetDrawTextureTexCoords(u1, v1, u2, v2);
1207
1208    int alpha;
1209    SkXfermode::Mode mode;
1210    getAlphaAndMode(paint, &alpha, &mode);
1211
1212    if (mSnapshot->transform->isPureTranslate()) {
1213        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1214        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1215
1216        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1217                texture->id, alpha / 255.0f, mode, texture->blend,
1218                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1219                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1220    } else {
1221        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1222                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1223                GL_TRIANGLE_STRIP, gMeshCount);
1224    }
1225
1226    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1227}
1228
1229void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1230        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1231        float left, float top, float right, float bottom, SkPaint* paint) {
1232    if (quickReject(left, top, right, bottom)) {
1233        return;
1234    }
1235
1236    glActiveTexture(gTextureUnits[0]);
1237    Texture* texture = mCaches.textureCache.get(bitmap);
1238    if (!texture) return;
1239    const AutoTexture autoCleanup(texture);
1240    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1241
1242    int alpha;
1243    SkXfermode::Mode mode;
1244    getAlphaAndMode(paint, &alpha, &mode);
1245
1246    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1247            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1248
1249    if (mesh && mesh->verticesCount > 0) {
1250        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1251#if RENDER_LAYERS_AS_REGIONS
1252        // Mark the current layer dirty where we are going to draw the patch
1253        if (hasLayer() && mesh->hasEmptyQuads) {
1254            const float offsetX = left + mSnapshot->transform->getTranslateX();
1255            const float offsetY = top + mSnapshot->transform->getTranslateY();
1256            const size_t count = mesh->quads.size();
1257            for (size_t i = 0; i < count; i++) {
1258                const Rect& bounds = mesh->quads.itemAt(i);
1259                if (pureTranslate) {
1260                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1261                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1262                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1263                } else {
1264                    dirtyLayer(left + bounds.left, top + bounds.top,
1265                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1266                }
1267            }
1268        }
1269#endif
1270
1271        if (pureTranslate) {
1272            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1273            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1274
1275            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1276                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1277                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1278                    true, !mesh->hasEmptyQuads);
1279        } else {
1280            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1281                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1282                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1283                    true, !mesh->hasEmptyQuads);
1284        }
1285    }
1286}
1287
1288void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1289    if (mSnapshot->isIgnored()) return;
1290
1291    const bool isAA = paint->isAntiAlias();
1292    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1293    // A stroke width of 0 has a special meaningin Skia:
1294    // it draws an unscaled 1px wide line
1295    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1296
1297    int alpha;
1298    SkXfermode::Mode mode;
1299    getAlphaAndMode(paint, &alpha, &mode);
1300
1301    int verticesCount = count >> 2;
1302    int generatedVerticesCount = 0;
1303    if (!isHairLine) {
1304        // TODO: AA needs more vertices
1305        verticesCount *= 6;
1306    } else {
1307        // TODO: AA will be different
1308        verticesCount *= 2;
1309    }
1310
1311    TextureVertex lines[verticesCount];
1312    TextureVertex* vertex = &lines[0];
1313
1314    setupDraw();
1315    setupDrawColor(paint->getColor(), alpha);
1316    setupDrawColorFilter();
1317    setupDrawShader();
1318    setupDrawBlending(mode);
1319    setupDrawProgram();
1320    setupDrawModelViewIdentity();
1321    setupDrawColorUniforms();
1322    setupDrawColorFilterUniforms();
1323    setupDrawShaderIdentityUniforms();
1324    setupDrawMesh(vertex);
1325
1326    if (!isHairLine) {
1327        // TODO: Handle the AA case
1328        for (int i = 0; i < count; i += 4) {
1329            // a = start point, b = end point
1330            vec2 a(points[i], points[i + 1]);
1331            vec2 b(points[i + 2], points[i + 3]);
1332
1333            // Bias to snap to the same pixels as Skia
1334            a += 0.375;
1335            b += 0.375;
1336
1337            // Find the normal to the line
1338            vec2 n = (b - a).copyNormalized() * strokeWidth;
1339            float x = n.x;
1340            n.x = -n.y;
1341            n.y = x;
1342
1343            // Four corners of the rectangle defining a thick line
1344            vec2 p1 = a - n;
1345            vec2 p2 = a + n;
1346            vec2 p3 = b + n;
1347            vec2 p4 = b - n;
1348
1349            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1350            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1351            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1352            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1353
1354            if (!quickReject(left, top, right, bottom)) {
1355                // Draw the line as 2 triangles, could be optimized
1356                // by using only 4 vertices and the correct indices
1357                // Also we should probably used non textured vertices
1358                // when line AA is disabled to save on bandwidth
1359                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1360                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1361                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1362                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1363                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1364                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1365
1366                generatedVerticesCount += 6;
1367
1368                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1369            }
1370        }
1371
1372        if (generatedVerticesCount > 0) {
1373            // GL_LINE does not give the result we want to match Skia
1374            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1375        }
1376    } else {
1377        // TODO: Handle the AA case
1378        for (int i = 0; i < count; i += 4) {
1379            const float left = fmin(points[i], points[i + 1]);
1380            const float right = fmax(points[i], points[i + 1]);
1381            const float top = fmin(points[i + 2], points[i + 3]);
1382            const float bottom = fmax(points[i + 2], points[i + 3]);
1383
1384            if (!quickReject(left, top, right, bottom)) {
1385                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1386                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1387
1388                generatedVerticesCount += 2;
1389
1390                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1391            }
1392        }
1393
1394        if (generatedVerticesCount > 0) {
1395            glLineWidth(1.0f);
1396            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1397        }
1398    }
1399}
1400
1401void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1402    // No need to check against the clip, we fill the clip region
1403    if (mSnapshot->isIgnored()) return;
1404
1405    Rect& clip(*mSnapshot->clipRect);
1406    clip.snapToPixelBoundaries();
1407
1408    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1409}
1410
1411void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1412    if (!texture) return;
1413    const AutoTexture autoCleanup(texture);
1414
1415    const float x = left + texture->left - texture->offset;
1416    const float y = top + texture->top - texture->offset;
1417
1418    drawPathTexture(texture, x, y, paint);
1419}
1420
1421void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1422        float rx, float ry, SkPaint* paint) {
1423    if (mSnapshot->isIgnored()) return;
1424
1425    glActiveTexture(gTextureUnits[0]);
1426    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1427            right - left, bottom - top, rx, ry, paint);
1428    drawShape(left, top, texture, paint);
1429}
1430
1431void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1432    if (mSnapshot->isIgnored()) return;
1433
1434    glActiveTexture(gTextureUnits[0]);
1435    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1436    drawShape(x - radius, y - radius, texture, paint);
1437}
1438
1439void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1440    if (mSnapshot->isIgnored()) return;
1441
1442    glActiveTexture(gTextureUnits[0]);
1443    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1444    drawShape(left, top, texture, paint);
1445}
1446
1447void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1448        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1449    if (mSnapshot->isIgnored()) return;
1450
1451    if (fabs(sweepAngle) >= 360.0f) {
1452        drawOval(left, top, right, bottom, paint);
1453        return;
1454    }
1455
1456    glActiveTexture(gTextureUnits[0]);
1457    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1458            startAngle, sweepAngle, useCenter, paint);
1459    drawShape(left, top, texture, paint);
1460}
1461
1462void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1463        SkPaint* paint) {
1464    if (mSnapshot->isIgnored()) return;
1465
1466    glActiveTexture(gTextureUnits[0]);
1467    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1468    drawShape(left, top, texture, paint);
1469}
1470
1471void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1472    if (p->getStyle() != SkPaint::kFill_Style) {
1473        drawRectAsShape(left, top, right, bottom, p);
1474        return;
1475    }
1476
1477    if (quickReject(left, top, right, bottom)) {
1478        return;
1479    }
1480
1481    SkXfermode::Mode mode;
1482    if (!mCaches.extensions.hasFramebufferFetch()) {
1483        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1484        if (!isMode) {
1485            // Assume SRC_OVER
1486            mode = SkXfermode::kSrcOver_Mode;
1487        }
1488    } else {
1489        mode = getXfermode(p->getXfermode());
1490    }
1491
1492    int color = p->getColor();
1493    drawColorRect(left, top, right, bottom, color, mode);
1494}
1495
1496void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1497        float x, float y, SkPaint* paint) {
1498    if (text == NULL || count == 0) {
1499        return;
1500    }
1501    if (mSnapshot->isIgnored()) return;
1502
1503    paint->setAntiAlias(true);
1504
1505    float length = -1.0f;
1506    switch (paint->getTextAlign()) {
1507        case SkPaint::kCenter_Align:
1508            length = paint->measureText(text, bytesCount);
1509            x -= length / 2.0f;
1510            break;
1511        case SkPaint::kRight_Align:
1512            length = paint->measureText(text, bytesCount);
1513            x -= length;
1514            break;
1515        default:
1516            break;
1517    }
1518
1519    const float oldX = x;
1520    const float oldY = y;
1521    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1522    if (pureTranslate) {
1523        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1524        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1525    }
1526
1527    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1528    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1529            paint->getTextSize());
1530
1531    int alpha;
1532    SkXfermode::Mode mode;
1533    getAlphaAndMode(paint, &alpha, &mode);
1534
1535    if (mHasShadow) {
1536        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1537        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1538                count, mShadowRadius);
1539        const AutoTexture autoCleanup(shadow);
1540
1541        const float sx = x - shadow->left + mShadowDx;
1542        const float sy = y - shadow->top + mShadowDy;
1543
1544        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1545
1546        glActiveTexture(gTextureUnits[0]);
1547        setupDraw();
1548        setupDrawWithTexture(true);
1549        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1550        setupDrawBlending(true, mode);
1551        setupDrawProgram();
1552        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1553        setupDrawTexture(shadow->id);
1554        setupDrawPureColorUniforms();
1555        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1556
1557        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1558        finishDrawTexture();
1559    }
1560
1561    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1562        return;
1563    }
1564
1565    // Pick the appropriate texture filtering
1566    bool linearFilter = mSnapshot->transform->changesBounds();
1567    if (pureTranslate && !linearFilter) {
1568        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1569    }
1570
1571    glActiveTexture(gTextureUnits[0]);
1572    setupDraw();
1573    setupDrawDirtyRegionsDisabled();
1574    setupDrawWithTexture(true);
1575    setupDrawAlpha8Color(paint->getColor(), alpha);
1576    setupDrawColorFilter();
1577    setupDrawShader();
1578    setupDrawBlending(true, mode);
1579    setupDrawProgram();
1580    setupDrawModelView(x, y, x, y, pureTranslate, true);
1581    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1582    setupDrawPureColorUniforms();
1583    setupDrawColorFilterUniforms();
1584    setupDrawShaderUniforms(pureTranslate);
1585
1586    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1587    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1588
1589#if RENDER_LAYERS_AS_REGIONS
1590    bool hasActiveLayer = hasLayer();
1591#else
1592    bool hasActiveLayer = false;
1593#endif
1594    mCaches.unbindMeshBuffer();
1595
1596    // Tell font renderer the locations of position and texture coord
1597    // attributes so it can bind its data properly
1598    int positionSlot = mCaches.currentProgram->position;
1599    fontRenderer.setAttributeBindingSlots(positionSlot, mTexCoordsSlot);
1600    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1601            hasActiveLayer ? &bounds : NULL)) {
1602#if RENDER_LAYERS_AS_REGIONS
1603        if (hasActiveLayer) {
1604            if (!pureTranslate) {
1605                mSnapshot->transform->mapRect(bounds);
1606            }
1607            dirtyLayerUnchecked(bounds, getRegion());
1608        }
1609#endif
1610    }
1611
1612    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1613    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1614
1615    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1616}
1617
1618void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1619    if (mSnapshot->isIgnored()) return;
1620
1621    glActiveTexture(gTextureUnits[0]);
1622
1623    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1624    if (!texture) return;
1625    const AutoTexture autoCleanup(texture);
1626
1627    const float x = texture->left - texture->offset;
1628    const float y = texture->top - texture->offset;
1629
1630    drawPathTexture(texture, x, y, paint);
1631}
1632
1633void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1634    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1635        return;
1636    }
1637
1638    glActiveTexture(gTextureUnits[0]);
1639
1640    int alpha;
1641    SkXfermode::Mode mode;
1642    getAlphaAndMode(paint, &alpha, &mode);
1643
1644    layer->alpha = alpha;
1645    layer->mode = mode;
1646
1647#if RENDER_LAYERS_AS_REGIONS
1648    if (!layer->region.isEmpty()) {
1649        if (layer->region.isRect()) {
1650            const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1651            composeLayerRect(layer, r);
1652        } else if (layer->mesh) {
1653            const float a = alpha / 255.0f;
1654            const Rect& rect = layer->layer;
1655
1656            setupDraw();
1657            setupDrawWithTexture();
1658            setupDrawColor(a, a, a, a);
1659            setupDrawColorFilter();
1660            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1661            setupDrawProgram();
1662            setupDrawPureColorUniforms();
1663            setupDrawColorFilterUniforms();
1664            setupDrawTexture(layer->texture);
1665            // TODO: The current layer, if any, will be dirtied with the bounding box
1666            //       of the layer we are drawing. Since the layer we are drawing has
1667            //       a mesh, we know the dirty region, we should use it instead
1668            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1669            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1670
1671            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1672                    GL_UNSIGNED_SHORT, layer->meshIndices);
1673
1674            finishDrawTexture();
1675
1676#if DEBUG_LAYERS_AS_REGIONS
1677            drawRegionRects(layer->region);
1678#endif
1679        }
1680    }
1681#else
1682    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1683    composeLayerRect(layer, r);
1684#endif
1685}
1686
1687///////////////////////////////////////////////////////////////////////////////
1688// Shaders
1689///////////////////////////////////////////////////////////////////////////////
1690
1691void OpenGLRenderer::resetShader() {
1692    mShader = NULL;
1693}
1694
1695void OpenGLRenderer::setupShader(SkiaShader* shader) {
1696    mShader = shader;
1697    if (mShader) {
1698        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1699    }
1700}
1701
1702///////////////////////////////////////////////////////////////////////////////
1703// Color filters
1704///////////////////////////////////////////////////////////////////////////////
1705
1706void OpenGLRenderer::resetColorFilter() {
1707    mColorFilter = NULL;
1708}
1709
1710void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1711    mColorFilter = filter;
1712}
1713
1714///////////////////////////////////////////////////////////////////////////////
1715// Drop shadow
1716///////////////////////////////////////////////////////////////////////////////
1717
1718void OpenGLRenderer::resetShadow() {
1719    mHasShadow = false;
1720}
1721
1722void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1723    mHasShadow = true;
1724    mShadowRadius = radius;
1725    mShadowDx = dx;
1726    mShadowDy = dy;
1727    mShadowColor = color;
1728}
1729
1730///////////////////////////////////////////////////////////////////////////////
1731// Drawing implementation
1732///////////////////////////////////////////////////////////////////////////////
1733
1734void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1735        float x, float y, SkPaint* paint) {
1736    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1737        return;
1738    }
1739
1740    int alpha;
1741    SkXfermode::Mode mode;
1742    getAlphaAndMode(paint, &alpha, &mode);
1743
1744    setupDraw();
1745    setupDrawWithTexture(true);
1746    setupDrawAlpha8Color(paint->getColor(), alpha);
1747    setupDrawColorFilter();
1748    setupDrawShader();
1749    setupDrawBlending(true, mode);
1750    setupDrawProgram();
1751    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1752    setupDrawTexture(texture->id);
1753    setupDrawPureColorUniforms();
1754    setupDrawColorFilterUniforms();
1755    setupDrawShaderUniforms();
1756    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1757
1758    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1759
1760    finishDrawTexture();
1761}
1762
1763// Same values used by Skia
1764#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1765#define kStdUnderline_Offset    (1.0f / 9.0f)
1766#define kStdUnderline_Thickness (1.0f / 18.0f)
1767
1768void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1769        float x, float y, SkPaint* paint) {
1770    // Handle underline and strike-through
1771    uint32_t flags = paint->getFlags();
1772    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1773        float underlineWidth = length;
1774        // If length is > 0.0f, we already measured the text for the text alignment
1775        if (length <= 0.0f) {
1776            underlineWidth = paint->measureText(text, bytesCount);
1777        }
1778
1779        float offsetX = 0;
1780        switch (paint->getTextAlign()) {
1781            case SkPaint::kCenter_Align:
1782                offsetX = underlineWidth * 0.5f;
1783                break;
1784            case SkPaint::kRight_Align:
1785                offsetX = underlineWidth;
1786                break;
1787            default:
1788                break;
1789        }
1790
1791        if (underlineWidth > 0.0f) {
1792            const float textSize = paint->getTextSize();
1793            // TODO: Support stroke width < 1.0f when we have AA lines
1794            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
1795
1796            const float left = x - offsetX;
1797            float top = 0.0f;
1798
1799            int linesCount = 0;
1800            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
1801            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
1802
1803            const int pointsCount = 4 * linesCount;
1804            float points[pointsCount];
1805            int currentPoint = 0;
1806
1807            if (flags & SkPaint::kUnderlineText_Flag) {
1808                top = y + textSize * kStdUnderline_Offset;
1809                points[currentPoint++] = left;
1810                points[currentPoint++] = top;
1811                points[currentPoint++] = left + underlineWidth;
1812                points[currentPoint++] = top;
1813            }
1814
1815            if (flags & SkPaint::kStrikeThruText_Flag) {
1816                top = y + textSize * kStdStrikeThru_Offset;
1817                points[currentPoint++] = left;
1818                points[currentPoint++] = top;
1819                points[currentPoint++] = left + underlineWidth;
1820                points[currentPoint++] = top;
1821            }
1822
1823            SkPaint linesPaint(*paint);
1824            linesPaint.setStrokeWidth(strokeWidth);
1825
1826            drawLines(&points[0], pointsCount, &linesPaint);
1827        }
1828    }
1829}
1830
1831void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1832        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1833    // If a shader is set, preserve only the alpha
1834    if (mShader) {
1835        color |= 0x00ffffff;
1836    }
1837
1838    setupDraw();
1839    setupDrawColor(color);
1840    setupDrawShader();
1841    setupDrawColorFilter();
1842    setupDrawBlending(mode);
1843    setupDrawProgram();
1844    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1845    setupDrawColorUniforms();
1846    setupDrawShaderUniforms(ignoreTransform);
1847    setupDrawColorFilterUniforms();
1848    setupDrawSimpleMesh();
1849
1850    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1851}
1852
1853void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1854        Texture* texture, SkPaint* paint) {
1855    int alpha;
1856    SkXfermode::Mode mode;
1857    getAlphaAndMode(paint, &alpha, &mode);
1858
1859    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1860
1861    if (mSnapshot->transform->isPureTranslate()) {
1862        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1863        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1864
1865        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1866                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1867                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1868    } else {
1869        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1870                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1871                GL_TRIANGLE_STRIP, gMeshCount);
1872    }
1873}
1874
1875void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1876        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1877    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1878            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1879}
1880
1881void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1882        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1883        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1884        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1885
1886    setupDraw();
1887    setupDrawWithTexture();
1888    setupDrawColor(alpha, alpha, alpha, alpha);
1889    setupDrawColorFilter();
1890    setupDrawBlending(blend, mode, swapSrcDst);
1891    setupDrawProgram();
1892    if (!dirty) {
1893        setupDrawDirtyRegionsDisabled();
1894    }
1895    if (!ignoreScale) {
1896        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1897    } else {
1898        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1899    }
1900    setupDrawPureColorUniforms();
1901    setupDrawColorFilterUniforms();
1902    setupDrawTexture(texture);
1903    setupDrawMesh(vertices, texCoords, vbo);
1904
1905    glDrawArrays(drawMode, 0, elementsCount);
1906
1907    finishDrawTexture();
1908}
1909
1910void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1911        ProgramDescription& description, bool swapSrcDst) {
1912    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1913    if (blend) {
1914        if (mode < SkXfermode::kPlus_Mode) {
1915            if (!mCaches.blend) {
1916                glEnable(GL_BLEND);
1917            }
1918
1919            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1920            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1921
1922            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1923                glBlendFunc(sourceMode, destMode);
1924                mCaches.lastSrcMode = sourceMode;
1925                mCaches.lastDstMode = destMode;
1926            }
1927        } else {
1928            // These blend modes are not supported by OpenGL directly and have
1929            // to be implemented using shaders. Since the shader will perform
1930            // the blending, turn blending off here
1931            if (mCaches.extensions.hasFramebufferFetch()) {
1932                description.framebufferMode = mode;
1933                description.swapSrcDst = swapSrcDst;
1934            }
1935
1936            if (mCaches.blend) {
1937                glDisable(GL_BLEND);
1938            }
1939            blend = false;
1940        }
1941    } else if (mCaches.blend) {
1942        glDisable(GL_BLEND);
1943    }
1944    mCaches.blend = blend;
1945}
1946
1947bool OpenGLRenderer::useProgram(Program* program) {
1948    if (!program->isInUse()) {
1949        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1950        program->use();
1951        mCaches.currentProgram = program;
1952        return false;
1953    }
1954    return true;
1955}
1956
1957void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1958    TextureVertex* v = &mMeshVertices[0];
1959    TextureVertex::setUV(v++, u1, v1);
1960    TextureVertex::setUV(v++, u2, v1);
1961    TextureVertex::setUV(v++, u1, v2);
1962    TextureVertex::setUV(v++, u2, v2);
1963}
1964
1965void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1966    if (paint) {
1967        if (!mCaches.extensions.hasFramebufferFetch()) {
1968            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1969            if (!isMode) {
1970                // Assume SRC_OVER
1971                *mode = SkXfermode::kSrcOver_Mode;
1972            }
1973        } else {
1974            *mode = getXfermode(paint->getXfermode());
1975        }
1976
1977        // Skia draws using the color's alpha channel if < 255
1978        // Otherwise, it uses the paint's alpha
1979        int color = paint->getColor();
1980        *alpha = (color >> 24) & 0xFF;
1981        if (*alpha == 255) {
1982            *alpha = paint->getAlpha();
1983        }
1984    } else {
1985        *mode = SkXfermode::kSrcOver_Mode;
1986        *alpha = 255;
1987    }
1988}
1989
1990SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1991    // In the future we should look at unifying the Porter-Duff modes and
1992    // SkXferModes so that we can use SkXfermode::IsMode(xfer, &mode).
1993    if (mode == NULL) {
1994        return SkXfermode::kSrcOver_Mode;
1995    }
1996    return mode->fMode;
1997}
1998
1999void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
2000    bool bound = false;
2001    if (wrapS != texture->wrapS) {
2002        glBindTexture(GL_TEXTURE_2D, texture->id);
2003        bound = true;
2004        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
2005        texture->wrapS = wrapS;
2006    }
2007    if (wrapT != texture->wrapT) {
2008        if (!bound) {
2009            glBindTexture(GL_TEXTURE_2D, texture->id);
2010        }
2011        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
2012        texture->wrapT = wrapT;
2013    }
2014}
2015
2016}; // namespace uirenderer
2017}; // namespace android
2018