OpenGLRenderer.cpp revision f90f8171e6acb56f9f87093c01fd586f2140697a 
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    mSaveCount = 1;
148
149    glViewport(0, 0, mWidth, mHeight);
150
151    glDisable(GL_DITHER);
152
153    glEnable(GL_SCISSOR_TEST);
154    glScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
155    mSnapshot->setClip(left, top, right, bottom);
156
157    if (!opaque) {
158        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
159        glClear(GL_COLOR_BUFFER_BIT);
160    }
161}
162
163void OpenGLRenderer::finish() {
164#if DEBUG_OPENGL
165    GLenum status = GL_NO_ERROR;
166    while ((status = glGetError()) != GL_NO_ERROR) {
167        LOGD("GL error from OpenGLRenderer: 0x%x", status);
168        switch (status) {
169            case GL_OUT_OF_MEMORY:
170                LOGE("  OpenGLRenderer is out of memory!");
171                break;
172        }
173    }
174#endif
175#if DEBUG_MEMORY_USAGE
176    mCaches.dumpMemoryUsage();
177#else
178    if (mCaches.getDebugLevel() & kDebugMemory) {
179        mCaches.dumpMemoryUsage();
180    }
181#endif
182}
183
184void OpenGLRenderer::interrupt() {
185    if (mCaches.currentProgram) {
186        if (mCaches.currentProgram->isInUse()) {
187            mCaches.currentProgram->remove();
188            mCaches.currentProgram = NULL;
189        }
190    }
191    mCaches.unbindMeshBuffer();
192}
193
194void OpenGLRenderer::acquireContext() {
195    interrupt();
196}
197
198void OpenGLRenderer::resume() {
199    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
200
201    glEnable(GL_SCISSOR_TEST);
202    dirtyClip();
203
204    glDisable(GL_DITHER);
205
206    glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
207    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
208
209    mCaches.blend = true;
210    glEnable(GL_BLEND);
211    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
212    glBlendEquation(GL_FUNC_ADD);
213}
214
215void OpenGLRenderer::releaseContext() {
216    resume();
217}
218
219bool OpenGLRenderer::callDrawGLFunction(Functor *functor) {
220    interrupt();
221    if (mDirtyClip) {
222        setScissorFromClip();
223    }
224    status_t result = (*functor)();
225    resume();
226    return (result == 0) ? false : true;
227}
228
229///////////////////////////////////////////////////////////////////////////////
230// State management
231///////////////////////////////////////////////////////////////////////////////
232
233int OpenGLRenderer::getSaveCount() const {
234    return mSaveCount;
235}
236
237int OpenGLRenderer::save(int flags) {
238    return saveSnapshot(flags);
239}
240
241void OpenGLRenderer::restore() {
242    if (mSaveCount > 1) {
243        restoreSnapshot();
244    }
245}
246
247void OpenGLRenderer::restoreToCount(int saveCount) {
248    if (saveCount < 1) saveCount = 1;
249
250    while (mSaveCount > saveCount) {
251        restoreSnapshot();
252    }
253}
254
255int OpenGLRenderer::saveSnapshot(int flags) {
256    mSnapshot = new Snapshot(mSnapshot, flags);
257    return mSaveCount++;
258}
259
260bool OpenGLRenderer::restoreSnapshot() {
261    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
262    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
263    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
264
265    sp<Snapshot> current = mSnapshot;
266    sp<Snapshot> previous = mSnapshot->previous;
267
268    if (restoreOrtho) {
269        Rect& r = previous->viewport;
270        glViewport(r.left, r.top, r.right, r.bottom);
271        mOrthoMatrix.load(current->orthoMatrix);
272    }
273
274    mSaveCount--;
275    mSnapshot = previous;
276
277    if (restoreClip) {
278        dirtyClip();
279    }
280
281    if (restoreLayer) {
282        composeLayer(current, previous);
283    }
284
285    return restoreClip;
286}
287
288///////////////////////////////////////////////////////////////////////////////
289// Layers
290///////////////////////////////////////////////////////////////////////////////
291
292int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
293        SkPaint* p, int flags) {
294    const GLuint previousFbo = mSnapshot->fbo;
295    const int count = saveSnapshot(flags);
296
297    if (!mSnapshot->isIgnored()) {
298        int alpha = 255;
299        SkXfermode::Mode mode;
300
301        if (p) {
302            alpha = p->getAlpha();
303            if (!mCaches.extensions.hasFramebufferFetch()) {
304                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
305                if (!isMode) {
306                    // Assume SRC_OVER
307                    mode = SkXfermode::kSrcOver_Mode;
308                }
309            } else {
310                mode = getXfermode(p->getXfermode());
311            }
312        } else {
313            mode = SkXfermode::kSrcOver_Mode;
314        }
315
316        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
317    }
318
319    return count;
320}
321
322int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
323        int alpha, int flags) {
324    if (alpha >= 255 - ALPHA_THRESHOLD) {
325        return saveLayer(left, top, right, bottom, NULL, flags);
326    } else {
327        SkPaint paint;
328        paint.setAlpha(alpha);
329        return saveLayer(left, top, right, bottom, &paint, flags);
330    }
331}
332
333/**
334 * Layers are viewed by Skia are slightly different than layers in image editing
335 * programs (for instance.) When a layer is created, previously created layers
336 * and the frame buffer still receive every drawing command. For instance, if a
337 * layer is created and a shape intersecting the bounds of the layers and the
338 * framebuffer is draw, the shape will be drawn on both (unless the layer was
339 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
340 *
341 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
342 * texture. Unfortunately, this is inefficient as it requires every primitive to
343 * be drawn n + 1 times, where n is the number of active layers. In practice this
344 * means, for every primitive:
345 *   - Switch active frame buffer
346 *   - Change viewport, clip and projection matrix
347 *   - Issue the drawing
348 *
349 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
350 * To avoid this, layers are implemented in a different way here, at least in the
351 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
352 * is set. When this flag is set we can redirect all drawing operations into a
353 * single FBO.
354 *
355 * This implementation relies on the frame buffer being at least RGBA 8888. When
356 * a layer is created, only a texture is created, not an FBO. The content of the
357 * frame buffer contained within the layer's bounds is copied into this texture
358 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
359 * buffer and drawing continues as normal. This technique therefore treats the
360 * frame buffer as a scratch buffer for the layers.
361 *
362 * To compose the layers back onto the frame buffer, each layer texture
363 * (containing the original frame buffer data) is drawn as a simple quad over
364 * the frame buffer. The trick is that the quad is set as the composition
365 * destination in the blending equation, and the frame buffer becomes the source
366 * of the composition.
367 *
368 * Drawing layers with an alpha value requires an extra step before composition.
369 * An empty quad is drawn over the layer's region in the frame buffer. This quad
370 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
371 * quad is used to multiply the colors in the frame buffer. This is achieved by
372 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
373 * GL_ZERO, GL_SRC_ALPHA.
374 *
375 * Because glCopyTexImage2D() can be slow, an alternative implementation might
376 * be use to draw a single clipped layer. The implementation described above
377 * is correct in every case.
378 *
379 * (1) The frame buffer is actually not cleared right away. To allow the GPU
380 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
381 *     buffer is left untouched until the first drawing operation. Only when
382 *     something actually gets drawn are the layers regions cleared.
383 */
384bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
385        float right, float bottom, int alpha, SkXfermode::Mode mode,
386        int flags, GLuint previousFbo) {
387    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
388    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
389
390    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
391
392    // Window coordinates of the layer
393    Rect bounds(left, top, right, bottom);
394    if (fboLayer) {
395        // Clear the previous layer regions before we change the viewport
396        clearLayerRegions();
397    } else {
398        mSnapshot->transform->mapRect(bounds);
399
400        // Layers only make sense if they are in the framebuffer's bounds
401        bounds.intersect(*snapshot->clipRect);
402
403        // We cannot work with sub-pixels in this case
404        bounds.snapToPixelBoundaries();
405
406        // When the layer is not an FBO, we may use glCopyTexImage so we
407        // need to make sure the layer does not extend outside the bounds
408        // of the framebuffer
409        bounds.intersect(snapshot->previous->viewport);
410    }
411
412    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
413            bounds.getHeight() > mCaches.maxTextureSize) {
414        snapshot->empty = fboLayer;
415    } else {
416        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
417    }
418
419    // Bail out if we won't draw in this snapshot
420    if (snapshot->invisible || snapshot->empty) {
421        return false;
422    }
423
424    glActiveTexture(gTextureUnits[0]);
425    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
426    if (!layer) {
427        return false;
428    }
429
430    layer->mode = mode;
431    layer->alpha = alpha;
432    layer->layer.set(bounds);
433    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
434            bounds.getWidth() / float(layer->width), 0.0f);
435    layer->colorFilter = mColorFilter;
436
437    // Save the layer in the snapshot
438    snapshot->flags |= Snapshot::kFlagIsLayer;
439    snapshot->layer = layer;
440
441    if (fboLayer) {
442        return createFboLayer(layer, bounds, snapshot, previousFbo);
443    } else {
444        // Copy the framebuffer into the layer
445        glBindTexture(GL_TEXTURE_2D, layer->texture);
446        if (!bounds.isEmpty()) {
447            if (layer->empty) {
448                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
449                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
450                layer->empty = false;
451            } else {
452                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
453                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
454            }
455            // Enqueue the buffer coordinates to clear the corresponding region later
456            mLayers.push(new Rect(bounds));
457        }
458    }
459
460    return true;
461}
462
463bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
464        GLuint previousFbo) {
465    layer->fbo = mCaches.fboCache.get();
466
467#if RENDER_LAYERS_AS_REGIONS
468    snapshot->region = &snapshot->layer->region;
469    snapshot->flags |= Snapshot::kFlagFboTarget;
470#endif
471
472    Rect clip(bounds);
473    snapshot->transform->mapRect(clip);
474    clip.intersect(*snapshot->clipRect);
475    clip.snapToPixelBoundaries();
476    clip.intersect(snapshot->previous->viewport);
477
478    mat4 inverse;
479    inverse.loadInverse(*mSnapshot->transform);
480
481    inverse.mapRect(clip);
482    clip.snapToPixelBoundaries();
483    clip.intersect(bounds);
484    clip.translate(-bounds.left, -bounds.top);
485
486    snapshot->flags |= Snapshot::kFlagIsFboLayer;
487    snapshot->fbo = layer->fbo;
488    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
489    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
490    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
491    snapshot->height = bounds.getHeight();
492    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
493    snapshot->orthoMatrix.load(mOrthoMatrix);
494
495    // Bind texture to FBO
496    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
497    glBindTexture(GL_TEXTURE_2D, layer->texture);
498
499    // Initialize the texture if needed
500    if (layer->empty) {
501        layer->empty = false;
502        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
503                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
504    }
505
506    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
507            layer->texture, 0);
508
509#if DEBUG_LAYERS_AS_REGIONS
510    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
511    if (status != GL_FRAMEBUFFER_COMPLETE) {
512        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
513
514        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
515        glDeleteTextures(1, &layer->texture);
516        mCaches.fboCache.put(layer->fbo);
517
518        delete layer;
519
520        return false;
521    }
522#endif
523
524    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
525    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
526            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
527    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
528    glClear(GL_COLOR_BUFFER_BIT);
529
530    dirtyClip();
531
532    // Change the ortho projection
533    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
534    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
535
536    return true;
537}
538
539/**
540 * Read the documentation of createLayer() before doing anything in this method.
541 */
542void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
543    if (!current->layer) {
544        LOGE("Attempting to compose a layer that does not exist");
545        return;
546    }
547
548    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
549
550    if (fboLayer) {
551        // Unbind current FBO and restore previous one
552        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
553    }
554
555    Layer* layer = current->layer;
556    const Rect& rect = layer->layer;
557
558    if (!fboLayer && layer->alpha < 255) {
559        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
560                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
561        // Required below, composeLayerRect() will divide by 255
562        layer->alpha = 255;
563    }
564
565    mCaches.unbindMeshBuffer();
566
567    glActiveTexture(gTextureUnits[0]);
568
569    // When the layer is stored in an FBO, we can save a bit of fillrate by
570    // drawing only the dirty region
571    if (fboLayer) {
572        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
573        if (layer->colorFilter) {
574            setupColorFilter(layer->colorFilter);
575        }
576        composeLayerRegion(layer, rect);
577        if (layer->colorFilter) {
578            resetColorFilter();
579        }
580    } else {
581        if (!rect.isEmpty()) {
582            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
583            composeLayerRect(layer, rect, true);
584        }
585    }
586
587    if (fboLayer) {
588        // Detach the texture from the FBO
589        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
590        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
591        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
592
593        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
594        mCaches.fboCache.put(current->fbo);
595    }
596
597    dirtyClip();
598
599    // Failing to add the layer to the cache should happen only if the layer is too large
600    if (!mCaches.layerCache.put(layer)) {
601        LAYER_LOGD("Deleting layer");
602        glDeleteTextures(1, &layer->texture);
603        delete layer;
604    }
605}
606
607void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
608    const Rect& texCoords = layer->texCoords;
609    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
610
611    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
612            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
613            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
614
615    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
616}
617
618void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
619#if RENDER_LAYERS_AS_REGIONS
620    if (layer->region.isRect()) {
621        composeLayerRect(layer, rect);
622        layer->region.clear();
623        return;
624    }
625
626    if (!layer->region.isEmpty()) {
627        size_t count;
628        const android::Rect* rects = layer->region.getArray(&count);
629
630        const float alpha = layer->alpha / 255.0f;
631        const float texX = 1.0f / float(layer->width);
632        const float texY = 1.0f / float(layer->height);
633        const float height = rect.getHeight();
634
635        TextureVertex* mesh = mCaches.getRegionMesh();
636        GLsizei numQuads = 0;
637
638        setupDraw();
639        setupDrawWithTexture();
640        setupDrawColor(alpha, alpha, alpha, alpha);
641        setupDrawColorFilter();
642        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
643        setupDrawProgram();
644        setupDrawDirtyRegionsDisabled();
645        setupDrawPureColorUniforms();
646        setupDrawColorFilterUniforms();
647        setupDrawTexture(layer->texture);
648        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
649        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
650
651        for (size_t i = 0; i < count; i++) {
652            const android::Rect* r = &rects[i];
653
654            const float u1 = r->left * texX;
655            const float v1 = (height - r->top) * texY;
656            const float u2 = r->right * texX;
657            const float v2 = (height - r->bottom) * texY;
658
659            // TODO: Reject quads outside of the clip
660            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
661            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
662            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
663            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
664
665            numQuads++;
666
667            if (numQuads >= REGION_MESH_QUAD_COUNT) {
668                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
669                numQuads = 0;
670                mesh = mCaches.getRegionMesh();
671            }
672        }
673
674        if (numQuads > 0) {
675            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
676        }
677
678        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
679        finishDrawTexture();
680
681#if DEBUG_LAYERS_AS_REGIONS
682        uint32_t colors[] = {
683                0x7fff0000, 0x7f00ff00,
684                0x7f0000ff, 0x7fff00ff,
685        };
686
687        int offset = 0;
688        int32_t top = rects[0].top;
689        int i = 0;
690
691        for (size_t i = 0; i < count; i++) {
692            if (top != rects[i].top) {
693                offset ^= 0x2;
694                top = rects[i].top;
695            }
696
697            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
698            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
699                    SkXfermode::kSrcOver_Mode);
700        }
701#endif
702
703        layer->region.clear();
704    }
705#else
706    composeLayerRect(layer, rect);
707#endif
708}
709
710void OpenGLRenderer::dirtyLayer(const float left, const float top,
711        const float right, const float bottom, const mat4 transform) {
712#if RENDER_LAYERS_AS_REGIONS
713    if (hasLayer()) {
714        Rect bounds(left, top, right, bottom);
715        transform.mapRect(bounds);
716        dirtyLayerUnchecked(bounds, getRegion());
717    }
718#endif
719}
720
721void OpenGLRenderer::dirtyLayer(const float left, const float top,
722        const float right, const float bottom) {
723#if RENDER_LAYERS_AS_REGIONS
724    if (hasLayer()) {
725        Rect bounds(left, top, right, bottom);
726        dirtyLayerUnchecked(bounds, getRegion());
727    }
728#endif
729}
730
731void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
732#if RENDER_LAYERS_AS_REGIONS
733    if (bounds.intersect(*mSnapshot->clipRect)) {
734        bounds.snapToPixelBoundaries();
735        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
736        if (!dirty.isEmpty()) {
737            region->orSelf(dirty);
738        }
739    }
740#endif
741}
742
743void OpenGLRenderer::clearLayerRegions() {
744    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
745
746    Rect clipRect(*mSnapshot->clipRect);
747    clipRect.snapToPixelBoundaries();
748
749    for (uint32_t i = 0; i < mLayers.size(); i++) {
750        Rect* bounds = mLayers.itemAt(i);
751        if (clipRect.intersects(*bounds)) {
752            // Clear the framebuffer where the layer will draw
753            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
754                    bounds->getWidth(), bounds->getHeight());
755            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
756            glClear(GL_COLOR_BUFFER_BIT);
757
758            // Restore the clip
759            dirtyClip();
760        }
761
762        delete bounds;
763    }
764
765    mLayers.clear();
766}
767
768///////////////////////////////////////////////////////////////////////////////
769// Transforms
770///////////////////////////////////////////////////////////////////////////////
771
772void OpenGLRenderer::translate(float dx, float dy) {
773    mSnapshot->transform->translate(dx, dy, 0.0f);
774}
775
776void OpenGLRenderer::rotate(float degrees) {
777    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
778}
779
780void OpenGLRenderer::scale(float sx, float sy) {
781    mSnapshot->transform->scale(sx, sy, 1.0f);
782}
783
784void OpenGLRenderer::skew(float sx, float sy) {
785    mSnapshot->transform->skew(sx, sy);
786}
787
788void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
789    mSnapshot->transform->load(*matrix);
790}
791
792const float* OpenGLRenderer::getMatrix() const {
793    if (mSnapshot->fbo != 0) {
794        return &mSnapshot->transform->data[0];
795    }
796    return &mIdentity.data[0];
797}
798
799void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
800    mSnapshot->transform->copyTo(*matrix);
801}
802
803void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
804    SkMatrix transform;
805    mSnapshot->transform->copyTo(transform);
806    transform.preConcat(*matrix);
807    mSnapshot->transform->load(transform);
808}
809
810///////////////////////////////////////////////////////////////////////////////
811// Clipping
812///////////////////////////////////////////////////////////////////////////////
813
814void OpenGLRenderer::setScissorFromClip() {
815    Rect clip(*mSnapshot->clipRect);
816    clip.snapToPixelBoundaries();
817    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
818    mDirtyClip = false;
819}
820
821const Rect& OpenGLRenderer::getClipBounds() {
822    return mSnapshot->getLocalClip();
823}
824
825bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
826    if (mSnapshot->isIgnored()) {
827        return true;
828    }
829
830    Rect r(left, top, right, bottom);
831    mSnapshot->transform->mapRect(r);
832    r.snapToPixelBoundaries();
833
834    Rect clipRect(*mSnapshot->clipRect);
835    clipRect.snapToPixelBoundaries();
836
837    return !clipRect.intersects(r);
838}
839
840bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
841    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
842    if (clipped) {
843        dirtyClip();
844    }
845    return !mSnapshot->clipRect->isEmpty();
846}
847
848///////////////////////////////////////////////////////////////////////////////
849// Drawing commands
850///////////////////////////////////////////////////////////////////////////////
851
852void OpenGLRenderer::setupDraw() {
853    clearLayerRegions();
854    if (mDirtyClip) {
855        setScissorFromClip();
856    }
857    mDescription.reset();
858    mSetShaderColor = false;
859    mColorSet = false;
860    mColorA = mColorR = mColorG = mColorB = 0.0f;
861    mTextureUnit = 0;
862    mTrackDirtyRegions = true;
863    mTexCoordsSlot = -1;
864}
865
866void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
867    mDescription.hasTexture = true;
868    mDescription.hasAlpha8Texture = isAlpha8;
869}
870
871void OpenGLRenderer::setupDrawColor(int color) {
872    setupDrawColor(color, (color >> 24) & 0xFF);
873}
874
875void OpenGLRenderer::setupDrawColor(int color, int alpha) {
876    mColorA = alpha / 255.0f;
877    const float a = mColorA / 255.0f;
878    mColorR = a * ((color >> 16) & 0xFF);
879    mColorG = a * ((color >>  8) & 0xFF);
880    mColorB = a * ((color      ) & 0xFF);
881    mColorSet = true;
882    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
883}
884
885void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
886    mColorA = alpha / 255.0f;
887    const float a = mColorA / 255.0f;
888    mColorR = a * ((color >> 16) & 0xFF);
889    mColorG = a * ((color >>  8) & 0xFF);
890    mColorB = a * ((color      ) & 0xFF);
891    mColorSet = true;
892    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
893}
894
895void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
896    mColorA = a;
897    mColorR = r;
898    mColorG = g;
899    mColorB = b;
900    mColorSet = true;
901    mSetShaderColor = mDescription.setColor(r, g, b, a);
902}
903
904void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
905    mColorA = a;
906    mColorR = r;
907    mColorG = g;
908    mColorB = b;
909    mColorSet = true;
910    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
911}
912
913void OpenGLRenderer::setupDrawShader() {
914    if (mShader) {
915        mShader->describe(mDescription, mCaches.extensions);
916    }
917}
918
919void OpenGLRenderer::setupDrawColorFilter() {
920    if (mColorFilter) {
921        mColorFilter->describe(mDescription, mCaches.extensions);
922    }
923}
924
925void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
926    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
927            mDescription, swapSrcDst);
928}
929
930void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
931    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
932            mDescription, swapSrcDst);
933}
934
935void OpenGLRenderer::setupDrawProgram() {
936    useProgram(mCaches.programCache.get(mDescription));
937}
938
939void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
940    mTrackDirtyRegions = false;
941}
942
943void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
944        bool ignoreTransform) {
945    mModelView.loadTranslate(left, top, 0.0f);
946    if (!ignoreTransform) {
947        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
948        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
949    } else {
950        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
951        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
952    }
953}
954
955void OpenGLRenderer::setupDrawModelViewIdentity() {
956    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
957}
958
959void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
960        bool ignoreTransform, bool ignoreModelView) {
961    if (!ignoreModelView) {
962        mModelView.loadTranslate(left, top, 0.0f);
963        mModelView.scale(right - left, bottom - top, 1.0f);
964    } else {
965        mModelView.loadIdentity();
966    }
967    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
968    if (!ignoreTransform) {
969        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
970        if (mTrackDirtyRegions && dirty) {
971            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
972        }
973    } else {
974        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
975        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
976    }
977}
978
979void OpenGLRenderer::setupDrawColorUniforms() {
980    if (mColorSet || (mShader && mSetShaderColor)) {
981        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
982    }
983}
984
985void OpenGLRenderer::setupDrawPureColorUniforms() {
986    if (mSetShaderColor) {
987        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
988    }
989}
990
991void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
992    if (mShader) {
993        if (ignoreTransform) {
994            mModelView.loadInverse(*mSnapshot->transform);
995        }
996        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
997    }
998}
999
1000void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1001    if (mShader) {
1002        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1003    }
1004}
1005
1006void OpenGLRenderer::setupDrawColorFilterUniforms() {
1007    if (mColorFilter) {
1008        mColorFilter->setupProgram(mCaches.currentProgram);
1009    }
1010}
1011
1012void OpenGLRenderer::setupDrawSimpleMesh() {
1013    mCaches.bindMeshBuffer();
1014    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1015            gMeshStride, 0);
1016}
1017
1018void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1019    bindTexture(texture);
1020    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1021
1022    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1023    glEnableVertexAttribArray(mTexCoordsSlot);
1024}
1025
1026void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1027    if (!vertices) {
1028        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1029    } else {
1030        mCaches.unbindMeshBuffer();
1031    }
1032    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1033            gMeshStride, vertices);
1034    if (mTexCoordsSlot > 0) {
1035        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1036    }
1037}
1038
1039void OpenGLRenderer::finishDrawTexture() {
1040    glDisableVertexAttribArray(mTexCoordsSlot);
1041}
1042
1043///////////////////////////////////////////////////////////////////////////////
1044// Drawing
1045///////////////////////////////////////////////////////////////////////////////
1046
1047bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t level) {
1048    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1049    // will be performed by the display list itself
1050    if (displayList) {
1051        return displayList->replay(*this, level);
1052    }
1053    return false;
1054}
1055
1056void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1057    const float right = left + bitmap->width();
1058    const float bottom = top + bitmap->height();
1059
1060    if (quickReject(left, top, right, bottom)) {
1061        return;
1062    }
1063
1064    glActiveTexture(gTextureUnits[0]);
1065    Texture* texture = mCaches.textureCache.get(bitmap);
1066    if (!texture) return;
1067    const AutoTexture autoCleanup(texture);
1068
1069    drawTextureRect(left, top, right, bottom, texture, paint);
1070}
1071
1072void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1073    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1074    const mat4 transform(*matrix);
1075    transform.mapRect(r);
1076
1077    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1078        return;
1079    }
1080
1081    glActiveTexture(gTextureUnits[0]);
1082    Texture* texture = mCaches.textureCache.get(bitmap);
1083    if (!texture) return;
1084    const AutoTexture autoCleanup(texture);
1085
1086    // This could be done in a cheaper way, all we need is pass the matrix
1087    // to the vertex shader. The save/restore is a bit overkill.
1088    save(SkCanvas::kMatrix_SaveFlag);
1089    concatMatrix(matrix);
1090    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1091    restore();
1092}
1093
1094void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1095        float* vertices, int* colors, SkPaint* paint) {
1096    // TODO: Do a quickReject
1097    if (!vertices || mSnapshot->isIgnored()) {
1098        return;
1099    }
1100
1101    glActiveTexture(gTextureUnits[0]);
1102    Texture* texture = mCaches.textureCache.get(bitmap);
1103    if (!texture) return;
1104    const AutoTexture autoCleanup(texture);
1105    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1106
1107    int alpha;
1108    SkXfermode::Mode mode;
1109    getAlphaAndMode(paint, &alpha, &mode);
1110
1111    const uint32_t count = meshWidth * meshHeight * 6;
1112
1113    // TODO: Support the colors array
1114    TextureVertex mesh[count];
1115    TextureVertex* vertex = mesh;
1116    for (int32_t y = 0; y < meshHeight; y++) {
1117        for (int32_t x = 0; x < meshWidth; x++) {
1118            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1119
1120            float u1 = float(x) / meshWidth;
1121            float u2 = float(x + 1) / meshWidth;
1122            float v1 = float(y) / meshHeight;
1123            float v2 = float(y + 1) / meshHeight;
1124
1125            int ax = i + (meshWidth + 1) * 2;
1126            int ay = ax + 1;
1127            int bx = i;
1128            int by = bx + 1;
1129            int cx = i + 2;
1130            int cy = cx + 1;
1131            int dx = i + (meshWidth + 1) * 2 + 2;
1132            int dy = dx + 1;
1133
1134            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1135            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1136            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1137
1138            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1139            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1140            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1141        }
1142    }
1143
1144    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1145            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1146            GL_TRIANGLES, count);
1147}
1148
1149void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1150         float srcLeft, float srcTop, float srcRight, float srcBottom,
1151         float dstLeft, float dstTop, float dstRight, float dstBottom,
1152         SkPaint* paint) {
1153    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1154        return;
1155    }
1156
1157    glActiveTexture(gTextureUnits[0]);
1158    Texture* texture = mCaches.textureCache.get(bitmap);
1159    if (!texture) return;
1160    const AutoTexture autoCleanup(texture);
1161    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1162
1163    const float width = texture->width;
1164    const float height = texture->height;
1165
1166    const float u1 = srcLeft / width;
1167    const float v1 = srcTop / height;
1168    const float u2 = srcRight / width;
1169    const float v2 = srcBottom / height;
1170
1171    mCaches.unbindMeshBuffer();
1172    resetDrawTextureTexCoords(u1, v1, u2, v2);
1173
1174    int alpha;
1175    SkXfermode::Mode mode;
1176    getAlphaAndMode(paint, &alpha, &mode);
1177
1178    if (mSnapshot->transform->isPureTranslate()) {
1179        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1180        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1181
1182        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1183                texture->id, alpha / 255.0f, mode, texture->blend,
1184                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1185                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1186    } else {
1187        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1188                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1189                GL_TRIANGLE_STRIP, gMeshCount);
1190    }
1191
1192    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1193}
1194
1195void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1196        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1197        float left, float top, float right, float bottom, SkPaint* paint) {
1198    if (quickReject(left, top, right, bottom)) {
1199        return;
1200    }
1201
1202    glActiveTexture(gTextureUnits[0]);
1203    Texture* texture = mCaches.textureCache.get(bitmap);
1204    if (!texture) return;
1205    const AutoTexture autoCleanup(texture);
1206    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1207
1208    int alpha;
1209    SkXfermode::Mode mode;
1210    getAlphaAndMode(paint, &alpha, &mode);
1211
1212    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1213            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1214
1215    if (mesh && mesh->verticesCount > 0) {
1216        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1217#if RENDER_LAYERS_AS_REGIONS
1218        // Mark the current layer dirty where we are going to draw the patch
1219        if (hasLayer() && mesh->hasEmptyQuads) {
1220            const size_t count = mesh->quads.size();
1221            for (size_t i = 0; i < count; i++) {
1222                const Rect& bounds = mesh->quads.itemAt(i);
1223                if (pureTranslate) {
1224                    const float x = (int) floorf(bounds.left + 0.5f);
1225                    const float y = (int) floorf(bounds.top + 0.5f);
1226                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1227                            *mSnapshot->transform);
1228                } else {
1229                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1230                            *mSnapshot->transform);
1231                }
1232            }
1233        }
1234#endif
1235
1236        if (pureTranslate) {
1237            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1238            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1239
1240            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1241                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1242                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1243                    true, !mesh->hasEmptyQuads);
1244        } else {
1245            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1246                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1247                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1248                    true, !mesh->hasEmptyQuads);
1249        }
1250    }
1251}
1252
1253void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1254    if (mSnapshot->isIgnored()) return;
1255
1256    const bool isAA = paint->isAntiAlias();
1257    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1258    // A stroke width of 0 has a special meaningin Skia:
1259    // it draws an unscaled 1px wide line
1260    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1261
1262    int alpha;
1263    SkXfermode::Mode mode;
1264    getAlphaAndMode(paint, &alpha, &mode);
1265
1266    int verticesCount = count >> 2;
1267    int generatedVerticesCount = 0;
1268    if (!isHairLine) {
1269        // TODO: AA needs more vertices
1270        verticesCount *= 6;
1271    } else {
1272        // TODO: AA will be different
1273        verticesCount *= 2;
1274    }
1275
1276    TextureVertex lines[verticesCount];
1277    TextureVertex* vertex = &lines[0];
1278
1279    setupDraw();
1280    setupDrawColor(paint->getColor(), alpha);
1281    setupDrawColorFilter();
1282    setupDrawShader();
1283    setupDrawBlending(mode);
1284    setupDrawProgram();
1285    setupDrawModelViewIdentity();
1286    setupDrawColorUniforms();
1287    setupDrawColorFilterUniforms();
1288    setupDrawShaderIdentityUniforms();
1289    setupDrawMesh(vertex);
1290
1291    if (!isHairLine) {
1292        // TODO: Handle the AA case
1293        for (int i = 0; i < count; i += 4) {
1294            // a = start point, b = end point
1295            vec2 a(points[i], points[i + 1]);
1296            vec2 b(points[i + 2], points[i + 3]);
1297
1298            // Bias to snap to the same pixels as Skia
1299            a += 0.375;
1300            b += 0.375;
1301
1302            // Find the normal to the line
1303            vec2 n = (b - a).copyNormalized() * strokeWidth;
1304            float x = n.x;
1305            n.x = -n.y;
1306            n.y = x;
1307
1308            // Four corners of the rectangle defining a thick line
1309            vec2 p1 = a - n;
1310            vec2 p2 = a + n;
1311            vec2 p3 = b + n;
1312            vec2 p4 = b - n;
1313
1314            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1315            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1316            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1317            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1318
1319            if (!quickReject(left, top, right, bottom)) {
1320                // Draw the line as 2 triangles, could be optimized
1321                // by using only 4 vertices and the correct indices
1322                // Also we should probably used non textured vertices
1323                // when line AA is disabled to save on bandwidth
1324                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1325                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1326                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1327                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1328                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1329                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1330
1331                generatedVerticesCount += 6;
1332
1333                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1334            }
1335        }
1336
1337        if (generatedVerticesCount > 0) {
1338            // GL_LINE does not give the result we want to match Skia
1339            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1340        }
1341    } else {
1342        // TODO: Handle the AA case
1343        for (int i = 0; i < count; i += 4) {
1344            const float left = fmin(points[i], points[i + 1]);
1345            const float right = fmax(points[i], points[i + 1]);
1346            const float top = fmin(points[i + 2], points[i + 3]);
1347            const float bottom = fmax(points[i + 2], points[i + 3]);
1348
1349            if (!quickReject(left, top, right, bottom)) {
1350                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1351                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1352
1353                generatedVerticesCount += 2;
1354
1355                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1356            }
1357        }
1358
1359        if (generatedVerticesCount > 0) {
1360            glLineWidth(1.0f);
1361            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1362        }
1363    }
1364}
1365
1366void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1367    // No need to check against the clip, we fill the clip region
1368    if (mSnapshot->isIgnored()) return;
1369
1370    Rect& clip(*mSnapshot->clipRect);
1371    clip.snapToPixelBoundaries();
1372
1373    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1374}
1375
1376void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1377    if (!texture) return;
1378    const AutoTexture autoCleanup(texture);
1379
1380    const float x = left + texture->left - texture->offset;
1381    const float y = top + texture->top - texture->offset;
1382
1383    drawPathTexture(texture, x, y, paint);
1384}
1385
1386void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1387        float rx, float ry, SkPaint* paint) {
1388    if (mSnapshot->isIgnored()) return;
1389
1390    glActiveTexture(gTextureUnits[0]);
1391    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1392            right - left, bottom - top, rx, ry, paint);
1393    drawShape(left, top, texture, paint);
1394}
1395
1396void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1397    if (mSnapshot->isIgnored()) return;
1398
1399    glActiveTexture(gTextureUnits[0]);
1400    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1401    drawShape(x - radius, y - radius, texture, paint);
1402}
1403
1404void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1405    if (mSnapshot->isIgnored()) return;
1406
1407    glActiveTexture(gTextureUnits[0]);
1408    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1409    drawShape(left, top, texture, paint);
1410}
1411
1412void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1413        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1414    if (mSnapshot->isIgnored()) return;
1415
1416    if (fabs(sweepAngle) >= 360.0f) {
1417        drawOval(left, top, right, bottom, paint);
1418        return;
1419    }
1420
1421    glActiveTexture(gTextureUnits[0]);
1422    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1423            startAngle, sweepAngle, useCenter, paint);
1424    drawShape(left, top, texture, paint);
1425}
1426
1427void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1428        SkPaint* paint) {
1429    if (mSnapshot->isIgnored()) return;
1430
1431    glActiveTexture(gTextureUnits[0]);
1432    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1433    drawShape(left, top, texture, paint);
1434}
1435
1436void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1437    if (p->getStyle() != SkPaint::kFill_Style) {
1438        drawRectAsShape(left, top, right, bottom, p);
1439        return;
1440    }
1441
1442    if (quickReject(left, top, right, bottom)) {
1443        return;
1444    }
1445
1446    SkXfermode::Mode mode;
1447    if (!mCaches.extensions.hasFramebufferFetch()) {
1448        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1449        if (!isMode) {
1450            // Assume SRC_OVER
1451            mode = SkXfermode::kSrcOver_Mode;
1452        }
1453    } else {
1454        mode = getXfermode(p->getXfermode());
1455    }
1456
1457    int color = p->getColor();
1458    drawColorRect(left, top, right, bottom, color, mode);
1459}
1460
1461void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1462        float x, float y, SkPaint* paint) {
1463    if (text == NULL || count == 0) {
1464        return;
1465    }
1466    if (mSnapshot->isIgnored()) return;
1467
1468    paint->setAntiAlias(true);
1469
1470    float length = -1.0f;
1471    switch (paint->getTextAlign()) {
1472        case SkPaint::kCenter_Align:
1473            length = paint->measureText(text, bytesCount);
1474            x -= length / 2.0f;
1475            break;
1476        case SkPaint::kRight_Align:
1477            length = paint->measureText(text, bytesCount);
1478            x -= length;
1479            break;
1480        default:
1481            break;
1482    }
1483
1484    // TODO: Handle paint->getTextScaleX()
1485    const float oldX = x;
1486    const float oldY = y;
1487    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1488    if (pureTranslate) {
1489        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1490        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1491    }
1492
1493    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1494    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1495            paint->getTextSize());
1496
1497    int alpha;
1498    SkXfermode::Mode mode;
1499    getAlphaAndMode(paint, &alpha, &mode);
1500
1501    if (mHasShadow) {
1502        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1503        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1504                count, mShadowRadius);
1505        const AutoTexture autoCleanup(shadow);
1506
1507        const float sx = x - shadow->left + mShadowDx;
1508        const float sy = y - shadow->top + mShadowDy;
1509
1510        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1511
1512        glActiveTexture(gTextureUnits[0]);
1513        setupDraw();
1514        setupDrawWithTexture(true);
1515        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1516        setupDrawBlending(true, mode);
1517        setupDrawProgram();
1518        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1519        setupDrawTexture(shadow->id);
1520        setupDrawPureColorUniforms();
1521        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1522
1523        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1524        finishDrawTexture();
1525    }
1526
1527    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1528        return;
1529    }
1530
1531    // Pick the appropriate texture filtering
1532    bool linearFilter = mSnapshot->transform->changesBounds();
1533    if (pureTranslate && !linearFilter) {
1534        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1535    }
1536
1537    glActiveTexture(gTextureUnits[0]);
1538    setupDraw();
1539    setupDrawDirtyRegionsDisabled();
1540    setupDrawWithTexture(true);
1541    setupDrawAlpha8Color(paint->getColor(), alpha);
1542    setupDrawColorFilter();
1543    setupDrawShader();
1544    setupDrawBlending(true, mode);
1545    setupDrawProgram();
1546    setupDrawModelView(x, y, x, y, pureTranslate, true);
1547    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1548    setupDrawPureColorUniforms();
1549    setupDrawColorFilterUniforms();
1550    setupDrawShaderUniforms(pureTranslate);
1551
1552    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1553    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1554
1555#if RENDER_LAYERS_AS_REGIONS
1556    bool hasActiveLayer = hasLayer();
1557#else
1558    bool hasActiveLayer = false;
1559#endif
1560
1561    mCaches.unbindMeshBuffer();
1562    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1563            hasActiveLayer ? &bounds : NULL)) {
1564#if RENDER_LAYERS_AS_REGIONS
1565        if (hasActiveLayer) {
1566            if (!pureTranslate) {
1567                mSnapshot->transform->mapRect(bounds);
1568            }
1569            dirtyLayerUnchecked(bounds, getRegion());
1570        }
1571#endif
1572    }
1573
1574    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1575    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1576
1577    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1578}
1579
1580void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1581    if (mSnapshot->isIgnored()) return;
1582
1583    glActiveTexture(gTextureUnits[0]);
1584
1585    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1586    if (!texture) return;
1587    const AutoTexture autoCleanup(texture);
1588
1589    const float x = texture->left - texture->offset;
1590    const float y = texture->top - texture->offset;
1591
1592    drawPathTexture(texture, x, y, paint);
1593}
1594
1595void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1596    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1597        return;
1598    }
1599
1600    glActiveTexture(gTextureUnits[0]);
1601
1602    int alpha;
1603    SkXfermode::Mode mode;
1604    getAlphaAndMode(paint, &alpha, &mode);
1605
1606    layer->alpha = alpha;
1607    layer->mode = mode;
1608
1609#if RENDER_LAYERS_AS_REGIONS
1610    if (!layer->region.isEmpty()) {
1611        if (layer->region.isRect()) {
1612            const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1613            composeLayerRect(layer, r);
1614        } else if (layer->mesh) {
1615            const float a = alpha / 255.0f;
1616            const Rect& rect = layer->layer;
1617
1618            setupDraw();
1619            setupDrawWithTexture();
1620            setupDrawColor(a, a, a, a);
1621            setupDrawColorFilter();
1622            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1623            setupDrawProgram();
1624            setupDrawDirtyRegionsDisabled();
1625            setupDrawPureColorUniforms();
1626            setupDrawColorFilterUniforms();
1627            setupDrawTexture(layer->texture);
1628            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1629            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1630
1631            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1632                    GL_UNSIGNED_SHORT, layer->meshIndices);
1633
1634            finishDrawTexture();
1635        }
1636    }
1637#else
1638    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1639    composeLayerRect(layer, r);
1640#endif
1641}
1642
1643///////////////////////////////////////////////////////////////////////////////
1644// Shaders
1645///////////////////////////////////////////////////////////////////////////////
1646
1647void OpenGLRenderer::resetShader() {
1648    mShader = NULL;
1649}
1650
1651void OpenGLRenderer::setupShader(SkiaShader* shader) {
1652    mShader = shader;
1653    if (mShader) {
1654        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1655    }
1656}
1657
1658///////////////////////////////////////////////////////////////////////////////
1659// Color filters
1660///////////////////////////////////////////////////////////////////////////////
1661
1662void OpenGLRenderer::resetColorFilter() {
1663    mColorFilter = NULL;
1664}
1665
1666void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1667    mColorFilter = filter;
1668}
1669
1670///////////////////////////////////////////////////////////////////////////////
1671// Drop shadow
1672///////////////////////////////////////////////////////////////////////////////
1673
1674void OpenGLRenderer::resetShadow() {
1675    mHasShadow = false;
1676}
1677
1678void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1679    mHasShadow = true;
1680    mShadowRadius = radius;
1681    mShadowDx = dx;
1682    mShadowDy = dy;
1683    mShadowColor = color;
1684}
1685
1686///////////////////////////////////////////////////////////////////////////////
1687// Drawing implementation
1688///////////////////////////////////////////////////////////////////////////////
1689
1690void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1691        float x, float y, SkPaint* paint) {
1692    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1693        return;
1694    }
1695
1696    int alpha;
1697    SkXfermode::Mode mode;
1698    getAlphaAndMode(paint, &alpha, &mode);
1699
1700    setupDraw();
1701    setupDrawWithTexture(true);
1702    setupDrawAlpha8Color(paint->getColor(), alpha);
1703    setupDrawColorFilter();
1704    setupDrawShader();
1705    setupDrawBlending(true, mode);
1706    setupDrawProgram();
1707    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1708    setupDrawTexture(texture->id);
1709    setupDrawPureColorUniforms();
1710    setupDrawColorFilterUniforms();
1711    setupDrawShaderUniforms();
1712    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1713
1714    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1715
1716    finishDrawTexture();
1717}
1718
1719// Same values used by Skia
1720#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1721#define kStdUnderline_Offset    (1.0f / 9.0f)
1722#define kStdUnderline_Thickness (1.0f / 18.0f)
1723
1724void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1725        float x, float y, SkPaint* paint) {
1726    // Handle underline and strike-through
1727    uint32_t flags = paint->getFlags();
1728    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1729        float underlineWidth = length;
1730        // If length is > 0.0f, we already measured the text for the text alignment
1731        if (length <= 0.0f) {
1732            underlineWidth = paint->measureText(text, bytesCount);
1733        }
1734
1735        float offsetX = 0;
1736        switch (paint->getTextAlign()) {
1737            case SkPaint::kCenter_Align:
1738                offsetX = underlineWidth * 0.5f;
1739                break;
1740            case SkPaint::kRight_Align:
1741                offsetX = underlineWidth;
1742                break;
1743            default:
1744                break;
1745        }
1746
1747        if (underlineWidth > 0.0f) {
1748            const float textSize = paint->getTextSize();
1749            // TODO: Support stroke width < 1.0f when we have AA lines
1750            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
1751
1752            const float left = x - offsetX;
1753            float top = 0.0f;
1754
1755            int linesCount = 0;
1756            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
1757            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
1758
1759            const int pointsCount = 4 * linesCount;
1760            float points[pointsCount];
1761            int currentPoint = 0;
1762
1763            if (flags & SkPaint::kUnderlineText_Flag) {
1764                top = y + textSize * kStdUnderline_Offset;
1765                points[currentPoint++] = left;
1766                points[currentPoint++] = top;
1767                points[currentPoint++] = left + underlineWidth;
1768                points[currentPoint++] = top;
1769            }
1770
1771            if (flags & SkPaint::kStrikeThruText_Flag) {
1772                top = y + textSize * kStdStrikeThru_Offset;
1773                points[currentPoint++] = left;
1774                points[currentPoint++] = top;
1775                points[currentPoint++] = left + underlineWidth;
1776                points[currentPoint++] = top;
1777            }
1778
1779            SkPaint linesPaint(*paint);
1780            linesPaint.setStrokeWidth(strokeWidth);
1781
1782            drawLines(&points[0], pointsCount, &linesPaint);
1783        }
1784    }
1785}
1786
1787void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1788        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1789    // If a shader is set, preserve only the alpha
1790    if (mShader) {
1791        color |= 0x00ffffff;
1792    }
1793
1794    setupDraw();
1795    setupDrawColor(color);
1796    setupDrawShader();
1797    setupDrawColorFilter();
1798    setupDrawBlending(mode);
1799    setupDrawProgram();
1800    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1801    setupDrawColorUniforms();
1802    setupDrawShaderUniforms(ignoreTransform);
1803    setupDrawColorFilterUniforms();
1804    setupDrawSimpleMesh();
1805
1806    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1807}
1808
1809void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1810        Texture* texture, SkPaint* paint) {
1811    int alpha;
1812    SkXfermode::Mode mode;
1813    getAlphaAndMode(paint, &alpha, &mode);
1814
1815    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1816
1817    if (mSnapshot->transform->isPureTranslate()) {
1818        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1819        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1820
1821        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1822                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1823                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1824    } else {
1825        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1826                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1827                GL_TRIANGLE_STRIP, gMeshCount);
1828    }
1829}
1830
1831void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1832        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1833    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1834            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1835}
1836
1837void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1838        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1839        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1840        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1841
1842    setupDraw();
1843    setupDrawWithTexture();
1844    setupDrawColor(alpha, alpha, alpha, alpha);
1845    setupDrawColorFilter();
1846    setupDrawBlending(blend, mode, swapSrcDst);
1847    setupDrawProgram();
1848    if (!dirty) {
1849        setupDrawDirtyRegionsDisabled();
1850    }
1851    if (!ignoreScale) {
1852        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1853    } else {
1854        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1855    }
1856    setupDrawPureColorUniforms();
1857    setupDrawColorFilterUniforms();
1858    setupDrawTexture(texture);
1859    setupDrawMesh(vertices, texCoords, vbo);
1860
1861    glDrawArrays(drawMode, 0, elementsCount);
1862
1863    finishDrawTexture();
1864}
1865
1866void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1867        ProgramDescription& description, bool swapSrcDst) {
1868    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1869    if (blend) {
1870        if (mode < SkXfermode::kPlus_Mode) {
1871            if (!mCaches.blend) {
1872                glEnable(GL_BLEND);
1873            }
1874
1875            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1876            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1877
1878            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1879                glBlendFunc(sourceMode, destMode);
1880                mCaches.lastSrcMode = sourceMode;
1881                mCaches.lastDstMode = destMode;
1882            }
1883        } else {
1884            // These blend modes are not supported by OpenGL directly and have
1885            // to be implemented using shaders. Since the shader will perform
1886            // the blending, turn blending off here
1887            if (mCaches.extensions.hasFramebufferFetch()) {
1888                description.framebufferMode = mode;
1889                description.swapSrcDst = swapSrcDst;
1890            }
1891
1892            if (mCaches.blend) {
1893                glDisable(GL_BLEND);
1894            }
1895            blend = false;
1896        }
1897    } else if (mCaches.blend) {
1898        glDisable(GL_BLEND);
1899    }
1900    mCaches.blend = blend;
1901}
1902
1903bool OpenGLRenderer::useProgram(Program* program) {
1904    if (!program->isInUse()) {
1905        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1906        program->use();
1907        mCaches.currentProgram = program;
1908        return false;
1909    }
1910    return true;
1911}
1912
1913void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1914    TextureVertex* v = &mMeshVertices[0];
1915    TextureVertex::setUV(v++, u1, v1);
1916    TextureVertex::setUV(v++, u2, v1);
1917    TextureVertex::setUV(v++, u1, v2);
1918    TextureVertex::setUV(v++, u2, v2);
1919}
1920
1921void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1922    if (paint) {
1923        if (!mCaches.extensions.hasFramebufferFetch()) {
1924            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1925            if (!isMode) {
1926                // Assume SRC_OVER
1927                *mode = SkXfermode::kSrcOver_Mode;
1928            }
1929        } else {
1930            *mode = getXfermode(paint->getXfermode());
1931        }
1932
1933        // Skia draws using the color's alpha channel if < 255
1934        // Otherwise, it uses the paint's alpha
1935        int color = paint->getColor();
1936        *alpha = (color >> 24) & 0xFF;
1937        if (*alpha == 255) {
1938            *alpha = paint->getAlpha();
1939        }
1940    } else {
1941        *mode = SkXfermode::kSrcOver_Mode;
1942        *alpha = 255;
1943    }
1944}
1945
1946SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1947    if (mode == NULL) {
1948        return SkXfermode::kSrcOver_Mode;
1949    }
1950    return mode->fMode;
1951}
1952
1953void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1954    bool bound = false;
1955    if (wrapS != texture->wrapS) {
1956        glBindTexture(GL_TEXTURE_2D, texture->id);
1957        bound = true;
1958        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1959        texture->wrapS = wrapS;
1960    }
1961    if (wrapT != texture->wrapT) {
1962        if (!bound) {
1963            glBindTexture(GL_TEXTURE_2D, texture->id);
1964        }
1965        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1966        texture->wrapT = wrapT;
1967    }
1968}
1969
1970}; // namespace uirenderer
1971}; // namespace android
1972