OpenGLRenderer.cpp revision 4f09f5417b5c14fd31336dacfff86972e7885a03 
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::resume() {
195    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
196
197    glEnable(GL_SCISSOR_TEST);
198    dirtyClip();
199
200    glDisable(GL_DITHER);
201
202    glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
203    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
204
205    mCaches.blend = true;
206    glEnable(GL_BLEND);
207    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
208    glBlendEquation(GL_FUNC_ADD);
209}
210
211bool OpenGLRenderer::callDrawGLFunction(Functor *functor) {
212    interrupt();
213    if (mDirtyClip) {
214        setScissorFromClip();
215    }
216    status_t result = (*functor)();
217    resume();
218    return (result == 0) ? false : true;
219}
220
221///////////////////////////////////////////////////////////////////////////////
222// State management
223///////////////////////////////////////////////////////////////////////////////
224
225int OpenGLRenderer::getSaveCount() const {
226    return mSaveCount;
227}
228
229int OpenGLRenderer::save(int flags) {
230    return saveSnapshot(flags);
231}
232
233void OpenGLRenderer::restore() {
234    if (mSaveCount > 1) {
235        restoreSnapshot();
236    }
237}
238
239void OpenGLRenderer::restoreToCount(int saveCount) {
240    if (saveCount < 1) saveCount = 1;
241
242    while (mSaveCount > saveCount) {
243        restoreSnapshot();
244    }
245}
246
247int OpenGLRenderer::saveSnapshot(int flags) {
248    mSnapshot = new Snapshot(mSnapshot, flags);
249    return mSaveCount++;
250}
251
252bool OpenGLRenderer::restoreSnapshot() {
253    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
254    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
255    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
256
257    sp<Snapshot> current = mSnapshot;
258    sp<Snapshot> previous = mSnapshot->previous;
259
260    if (restoreOrtho) {
261        Rect& r = previous->viewport;
262        glViewport(r.left, r.top, r.right, r.bottom);
263        mOrthoMatrix.load(current->orthoMatrix);
264    }
265
266    mSaveCount--;
267    mSnapshot = previous;
268
269    if (restoreClip) {
270        dirtyClip();
271    }
272
273    if (restoreLayer) {
274        composeLayer(current, previous);
275    }
276
277    return restoreClip;
278}
279
280///////////////////////////////////////////////////////////////////////////////
281// Layers
282///////////////////////////////////////////////////////////////////////////////
283
284int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
285        SkPaint* p, int flags) {
286    const GLuint previousFbo = mSnapshot->fbo;
287    const int count = saveSnapshot(flags);
288
289    if (!mSnapshot->isIgnored()) {
290        int alpha = 255;
291        SkXfermode::Mode mode;
292
293        if (p) {
294            alpha = p->getAlpha();
295            if (!mCaches.extensions.hasFramebufferFetch()) {
296                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
297                if (!isMode) {
298                    // Assume SRC_OVER
299                    mode = SkXfermode::kSrcOver_Mode;
300                }
301            } else {
302                mode = getXfermode(p->getXfermode());
303            }
304        } else {
305            mode = SkXfermode::kSrcOver_Mode;
306        }
307
308        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
309    }
310
311    return count;
312}
313
314int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
315        int alpha, int flags) {
316    if (alpha >= 255 - ALPHA_THRESHOLD) {
317        return saveLayer(left, top, right, bottom, NULL, flags);
318    } else {
319        SkPaint paint;
320        paint.setAlpha(alpha);
321        return saveLayer(left, top, right, bottom, &paint, flags);
322    }
323}
324
325/**
326 * Layers are viewed by Skia are slightly different than layers in image editing
327 * programs (for instance.) When a layer is created, previously created layers
328 * and the frame buffer still receive every drawing command. For instance, if a
329 * layer is created and a shape intersecting the bounds of the layers and the
330 * framebuffer is draw, the shape will be drawn on both (unless the layer was
331 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
332 *
333 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
334 * texture. Unfortunately, this is inefficient as it requires every primitive to
335 * be drawn n + 1 times, where n is the number of active layers. In practice this
336 * means, for every primitive:
337 *   - Switch active frame buffer
338 *   - Change viewport, clip and projection matrix
339 *   - Issue the drawing
340 *
341 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
342 * To avoid this, layers are implemented in a different way here, at least in the
343 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
344 * is set. When this flag is set we can redirect all drawing operations into a
345 * single FBO.
346 *
347 * This implementation relies on the frame buffer being at least RGBA 8888. When
348 * a layer is created, only a texture is created, not an FBO. The content of the
349 * frame buffer contained within the layer's bounds is copied into this texture
350 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
351 * buffer and drawing continues as normal. This technique therefore treats the
352 * frame buffer as a scratch buffer for the layers.
353 *
354 * To compose the layers back onto the frame buffer, each layer texture
355 * (containing the original frame buffer data) is drawn as a simple quad over
356 * the frame buffer. The trick is that the quad is set as the composition
357 * destination in the blending equation, and the frame buffer becomes the source
358 * of the composition.
359 *
360 * Drawing layers with an alpha value requires an extra step before composition.
361 * An empty quad is drawn over the layer's region in the frame buffer. This quad
362 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
363 * quad is used to multiply the colors in the frame buffer. This is achieved by
364 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
365 * GL_ZERO, GL_SRC_ALPHA.
366 *
367 * Because glCopyTexImage2D() can be slow, an alternative implementation might
368 * be use to draw a single clipped layer. The implementation described above
369 * is correct in every case.
370 *
371 * (1) The frame buffer is actually not cleared right away. To allow the GPU
372 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
373 *     buffer is left untouched until the first drawing operation. Only when
374 *     something actually gets drawn are the layers regions cleared.
375 */
376bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
377        float right, float bottom, int alpha, SkXfermode::Mode mode,
378        int flags, GLuint previousFbo) {
379    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
380    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
381
382    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
383
384    // Window coordinates of the layer
385    Rect bounds(left, top, right, bottom);
386    if (fboLayer) {
387        // Clear the previous layer regions before we change the viewport
388        clearLayerRegions();
389    } else {
390        mSnapshot->transform->mapRect(bounds);
391
392        // Layers only make sense if they are in the framebuffer's bounds
393        bounds.intersect(*snapshot->clipRect);
394
395        // We cannot work with sub-pixels in this case
396        bounds.snapToPixelBoundaries();
397
398        // When the layer is not an FBO, we may use glCopyTexImage so we
399        // need to make sure the layer does not extend outside the bounds
400        // of the framebuffer
401        bounds.intersect(snapshot->previous->viewport);
402    }
403
404    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
405            bounds.getHeight() > mCaches.maxTextureSize) {
406        snapshot->empty = fboLayer;
407    } else {
408        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
409    }
410
411    // Bail out if we won't draw in this snapshot
412    if (snapshot->invisible || snapshot->empty) {
413        return false;
414    }
415
416    glActiveTexture(gTextureUnits[0]);
417    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
418    if (!layer) {
419        return false;
420    }
421
422    layer->mode = mode;
423    layer->alpha = alpha;
424    layer->layer.set(bounds);
425    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
426            bounds.getWidth() / float(layer->width), 0.0f);
427    layer->colorFilter = mColorFilter;
428
429    // Save the layer in the snapshot
430    snapshot->flags |= Snapshot::kFlagIsLayer;
431    snapshot->layer = layer;
432
433    if (fboLayer) {
434        return createFboLayer(layer, bounds, snapshot, previousFbo);
435    } else {
436        // Copy the framebuffer into the layer
437        glBindTexture(GL_TEXTURE_2D, layer->texture);
438        if (!bounds.isEmpty()) {
439            if (layer->empty) {
440                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
441                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
442                layer->empty = false;
443            } else {
444                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
445                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
446            }
447            // Enqueue the buffer coordinates to clear the corresponding region later
448            mLayers.push(new Rect(bounds));
449        }
450    }
451
452    return true;
453}
454
455bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
456        GLuint previousFbo) {
457    layer->fbo = mCaches.fboCache.get();
458
459#if RENDER_LAYERS_AS_REGIONS
460    snapshot->region = &snapshot->layer->region;
461    snapshot->flags |= Snapshot::kFlagFboTarget;
462#endif
463
464    Rect clip(bounds);
465    snapshot->transform->mapRect(clip);
466    clip.intersect(*snapshot->clipRect);
467    clip.snapToPixelBoundaries();
468    clip.intersect(snapshot->previous->viewport);
469
470    mat4 inverse;
471    inverse.loadInverse(*mSnapshot->transform);
472
473    inverse.mapRect(clip);
474    clip.snapToPixelBoundaries();
475    clip.intersect(bounds);
476    clip.translate(-bounds.left, -bounds.top);
477
478    snapshot->flags |= Snapshot::kFlagIsFboLayer;
479    snapshot->fbo = layer->fbo;
480    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
481    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
482    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
483    snapshot->height = bounds.getHeight();
484    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
485    snapshot->orthoMatrix.load(mOrthoMatrix);
486
487    // Bind texture to FBO
488    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
489    glBindTexture(GL_TEXTURE_2D, layer->texture);
490
491    // Initialize the texture if needed
492    if (layer->empty) {
493        layer->empty = false;
494        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
495                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
496    }
497
498    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
499            layer->texture, 0);
500
501#if DEBUG_LAYERS_AS_REGIONS
502    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
503    if (status != GL_FRAMEBUFFER_COMPLETE) {
504        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
505
506        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
507        glDeleteTextures(1, &layer->texture);
508        mCaches.fboCache.put(layer->fbo);
509
510        delete layer;
511
512        return false;
513    }
514#endif
515
516    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
517    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
518            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
519    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
520    glClear(GL_COLOR_BUFFER_BIT);
521
522    dirtyClip();
523
524    // Change the ortho projection
525    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
526    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
527
528    return true;
529}
530
531/**
532 * Read the documentation of createLayer() before doing anything in this method.
533 */
534void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
535    if (!current->layer) {
536        LOGE("Attempting to compose a layer that does not exist");
537        return;
538    }
539
540    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
541
542    if (fboLayer) {
543        // Unbind current FBO and restore previous one
544        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
545    }
546
547    Layer* layer = current->layer;
548    const Rect& rect = layer->layer;
549
550    if (!fboLayer && layer->alpha < 255) {
551        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
552                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
553        // Required below, composeLayerRect() will divide by 255
554        layer->alpha = 255;
555    }
556
557    mCaches.unbindMeshBuffer();
558
559    glActiveTexture(gTextureUnits[0]);
560
561    // When the layer is stored in an FBO, we can save a bit of fillrate by
562    // drawing only the dirty region
563    if (fboLayer) {
564        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
565        if (layer->colorFilter) {
566            setupColorFilter(layer->colorFilter);
567        }
568        composeLayerRegion(layer, rect);
569        if (layer->colorFilter) {
570            resetColorFilter();
571        }
572    } else {
573        if (!rect.isEmpty()) {
574            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
575            composeLayerRect(layer, rect, true);
576        }
577    }
578
579    if (fboLayer) {
580        // Detach the texture from the FBO
581        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
582        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
583        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
584
585        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
586        mCaches.fboCache.put(current->fbo);
587    }
588
589    dirtyClip();
590
591    // Failing to add the layer to the cache should happen only if the layer is too large
592    if (!mCaches.layerCache.put(layer)) {
593        LAYER_LOGD("Deleting layer");
594        glDeleteTextures(1, &layer->texture);
595        delete layer;
596    }
597}
598
599void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
600    const Rect& texCoords = layer->texCoords;
601    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
602
603    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
604            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
605            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
606
607    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
608}
609
610void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
611#if RENDER_LAYERS_AS_REGIONS
612    if (layer->region.isRect()) {
613        composeLayerRect(layer, rect);
614        layer->region.clear();
615        return;
616    }
617
618    if (!layer->region.isEmpty()) {
619        size_t count;
620        const android::Rect* rects = layer->region.getArray(&count);
621
622        const float alpha = layer->alpha / 255.0f;
623        const float texX = 1.0f / float(layer->width);
624        const float texY = 1.0f / float(layer->height);
625        const float height = rect.getHeight();
626
627        TextureVertex* mesh = mCaches.getRegionMesh();
628        GLsizei numQuads = 0;
629
630        setupDraw();
631        setupDrawWithTexture();
632        setupDrawColor(alpha, alpha, alpha, alpha);
633        setupDrawColorFilter();
634        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
635        setupDrawProgram();
636        setupDrawDirtyRegionsDisabled();
637        setupDrawPureColorUniforms();
638        setupDrawColorFilterUniforms();
639        setupDrawTexture(layer->texture);
640        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
641        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
642
643        for (size_t i = 0; i < count; i++) {
644            const android::Rect* r = &rects[i];
645
646            const float u1 = r->left * texX;
647            const float v1 = (height - r->top) * texY;
648            const float u2 = r->right * texX;
649            const float v2 = (height - r->bottom) * texY;
650
651            // TODO: Reject quads outside of the clip
652            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
653            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
654            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
655            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
656
657            numQuads++;
658
659            if (numQuads >= REGION_MESH_QUAD_COUNT) {
660                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
661                numQuads = 0;
662                mesh = mCaches.getRegionMesh();
663            }
664        }
665
666        if (numQuads > 0) {
667            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
668        }
669
670        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
671        finishDrawTexture();
672
673#if DEBUG_LAYERS_AS_REGIONS
674        uint32_t colors[] = {
675                0x7fff0000, 0x7f00ff00,
676                0x7f0000ff, 0x7fff00ff,
677        };
678
679        int offset = 0;
680        int32_t top = rects[0].top;
681        int i = 0;
682
683        for (size_t i = 0; i < count; i++) {
684            if (top != rects[i].top) {
685                offset ^= 0x2;
686                top = rects[i].top;
687            }
688
689            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
690            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
691                    SkXfermode::kSrcOver_Mode);
692        }
693#endif
694
695        layer->region.clear();
696    }
697#else
698    composeLayerRect(layer, rect);
699#endif
700}
701
702void OpenGLRenderer::dirtyLayer(const float left, const float top,
703        const float right, const float bottom, const mat4 transform) {
704#if RENDER_LAYERS_AS_REGIONS
705    if (hasLayer()) {
706        Rect bounds(left, top, right, bottom);
707        transform.mapRect(bounds);
708        dirtyLayerUnchecked(bounds, getRegion());
709    }
710#endif
711}
712
713void OpenGLRenderer::dirtyLayer(const float left, const float top,
714        const float right, const float bottom) {
715#if RENDER_LAYERS_AS_REGIONS
716    if (hasLayer()) {
717        Rect bounds(left, top, right, bottom);
718        dirtyLayerUnchecked(bounds, getRegion());
719    }
720#endif
721}
722
723void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
724#if RENDER_LAYERS_AS_REGIONS
725    if (bounds.intersect(*mSnapshot->clipRect)) {
726        bounds.snapToPixelBoundaries();
727        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
728        if (!dirty.isEmpty()) {
729            region->orSelf(dirty);
730        }
731    }
732#endif
733}
734
735void OpenGLRenderer::clearLayerRegions() {
736    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
737
738    Rect clipRect(*mSnapshot->clipRect);
739    clipRect.snapToPixelBoundaries();
740
741    for (uint32_t i = 0; i < mLayers.size(); i++) {
742        Rect* bounds = mLayers.itemAt(i);
743        if (clipRect.intersects(*bounds)) {
744            // Clear the framebuffer where the layer will draw
745            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
746                    bounds->getWidth(), bounds->getHeight());
747            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
748            glClear(GL_COLOR_BUFFER_BIT);
749
750            // Restore the clip
751            dirtyClip();
752        }
753
754        delete bounds;
755    }
756
757    mLayers.clear();
758}
759
760///////////////////////////////////////////////////////////////////////////////
761// Transforms
762///////////////////////////////////////////////////////////////////////////////
763
764void OpenGLRenderer::translate(float dx, float dy) {
765    mSnapshot->transform->translate(dx, dy, 0.0f);
766}
767
768void OpenGLRenderer::rotate(float degrees) {
769    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
770}
771
772void OpenGLRenderer::scale(float sx, float sy) {
773    mSnapshot->transform->scale(sx, sy, 1.0f);
774}
775
776void OpenGLRenderer::skew(float sx, float sy) {
777    mSnapshot->transform->skew(sx, sy);
778}
779
780void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
781    mSnapshot->transform->load(*matrix);
782}
783
784const float* OpenGLRenderer::getMatrix() const {
785    if (mSnapshot->fbo != 0) {
786        return &mSnapshot->transform->data[0];
787    }
788    return &mIdentity.data[0];
789}
790
791void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
792    mSnapshot->transform->copyTo(*matrix);
793}
794
795void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
796    SkMatrix transform;
797    mSnapshot->transform->copyTo(transform);
798    transform.preConcat(*matrix);
799    mSnapshot->transform->load(transform);
800}
801
802///////////////////////////////////////////////////////////////////////////////
803// Clipping
804///////////////////////////////////////////////////////////////////////////////
805
806void OpenGLRenderer::setScissorFromClip() {
807    Rect clip(*mSnapshot->clipRect);
808    clip.snapToPixelBoundaries();
809    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
810    mDirtyClip = false;
811}
812
813const Rect& OpenGLRenderer::getClipBounds() {
814    return mSnapshot->getLocalClip();
815}
816
817bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
818    if (mSnapshot->isIgnored()) {
819        return true;
820    }
821
822    Rect r(left, top, right, bottom);
823    mSnapshot->transform->mapRect(r);
824    r.snapToPixelBoundaries();
825
826    Rect clipRect(*mSnapshot->clipRect);
827    clipRect.snapToPixelBoundaries();
828
829    return !clipRect.intersects(r);
830}
831
832bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
833    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
834    if (clipped) {
835        dirtyClip();
836    }
837    return !mSnapshot->clipRect->isEmpty();
838}
839
840///////////////////////////////////////////////////////////////////////////////
841// Drawing commands
842///////////////////////////////////////////////////////////////////////////////
843
844void OpenGLRenderer::setupDraw() {
845    clearLayerRegions();
846    if (mDirtyClip) {
847        setScissorFromClip();
848    }
849    mDescription.reset();
850    mSetShaderColor = false;
851    mColorSet = false;
852    mColorA = mColorR = mColorG = mColorB = 0.0f;
853    mTextureUnit = 0;
854    mTrackDirtyRegions = true;
855    mTexCoordsSlot = -1;
856}
857
858void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
859    mDescription.hasTexture = true;
860    mDescription.hasAlpha8Texture = isAlpha8;
861}
862
863void OpenGLRenderer::setupDrawColor(int color) {
864    setupDrawColor(color, (color >> 24) & 0xFF);
865}
866
867void OpenGLRenderer::setupDrawColor(int color, int alpha) {
868    mColorA = alpha / 255.0f;
869    const float a = mColorA / 255.0f;
870    mColorR = a * ((color >> 16) & 0xFF);
871    mColorG = a * ((color >>  8) & 0xFF);
872    mColorB = a * ((color      ) & 0xFF);
873    mColorSet = true;
874    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
875}
876
877void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
878    mColorA = alpha / 255.0f;
879    const float a = mColorA / 255.0f;
880    mColorR = a * ((color >> 16) & 0xFF);
881    mColorG = a * ((color >>  8) & 0xFF);
882    mColorB = a * ((color      ) & 0xFF);
883    mColorSet = true;
884    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
885}
886
887void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
888    mColorA = a;
889    mColorR = r;
890    mColorG = g;
891    mColorB = b;
892    mColorSet = true;
893    mSetShaderColor = mDescription.setColor(r, g, b, a);
894}
895
896void OpenGLRenderer::setupDrawAlpha8Color(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.setAlpha8Color(r, g, b, a);
903}
904
905void OpenGLRenderer::setupDrawShader() {
906    if (mShader) {
907        mShader->describe(mDescription, mCaches.extensions);
908    }
909}
910
911void OpenGLRenderer::setupDrawColorFilter() {
912    if (mColorFilter) {
913        mColorFilter->describe(mDescription, mCaches.extensions);
914    }
915}
916
917void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
918    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
919            mDescription, swapSrcDst);
920}
921
922void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
923    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
924            mDescription, swapSrcDst);
925}
926
927void OpenGLRenderer::setupDrawProgram() {
928    useProgram(mCaches.programCache.get(mDescription));
929}
930
931void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
932    mTrackDirtyRegions = false;
933}
934
935void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
936        bool ignoreTransform) {
937    mModelView.loadTranslate(left, top, 0.0f);
938    if (!ignoreTransform) {
939        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
940        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
941    } else {
942        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
943        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
944    }
945}
946
947void OpenGLRenderer::setupDrawModelViewIdentity() {
948    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
949}
950
951void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
952        bool ignoreTransform, bool ignoreModelView) {
953    if (!ignoreModelView) {
954        mModelView.loadTranslate(left, top, 0.0f);
955        mModelView.scale(right - left, bottom - top, 1.0f);
956    } else {
957        mModelView.loadIdentity();
958    }
959    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
960    if (!ignoreTransform) {
961        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
962        if (mTrackDirtyRegions && dirty) {
963            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
964        }
965    } else {
966        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
967        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
968    }
969}
970
971void OpenGLRenderer::setupDrawColorUniforms() {
972    if (mColorSet || (mShader && mSetShaderColor)) {
973        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
974    }
975}
976
977void OpenGLRenderer::setupDrawPureColorUniforms() {
978    if (mSetShaderColor) {
979        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
980    }
981}
982
983void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
984    if (mShader) {
985        if (ignoreTransform) {
986            mModelView.loadInverse(*mSnapshot->transform);
987        }
988        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
989    }
990}
991
992void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
993    if (mShader) {
994        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
995    }
996}
997
998void OpenGLRenderer::setupDrawColorFilterUniforms() {
999    if (mColorFilter) {
1000        mColorFilter->setupProgram(mCaches.currentProgram);
1001    }
1002}
1003
1004void OpenGLRenderer::setupDrawSimpleMesh() {
1005    mCaches.bindMeshBuffer();
1006    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1007            gMeshStride, 0);
1008}
1009
1010void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1011    bindTexture(texture);
1012    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1013
1014    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1015    glEnableVertexAttribArray(mTexCoordsSlot);
1016}
1017
1018void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1019    if (!vertices) {
1020        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1021    } else {
1022        mCaches.unbindMeshBuffer();
1023    }
1024    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1025            gMeshStride, vertices);
1026    if (mTexCoordsSlot > 0) {
1027        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1028    }
1029}
1030
1031void OpenGLRenderer::finishDrawTexture() {
1032    glDisableVertexAttribArray(mTexCoordsSlot);
1033}
1034
1035///////////////////////////////////////////////////////////////////////////////
1036// Drawing
1037///////////////////////////////////////////////////////////////////////////////
1038
1039bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t level) {
1040    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1041    // will be performed by the display list itself
1042    if (displayList) {
1043        return displayList->replay(*this, level);
1044    }
1045    return false;
1046}
1047
1048void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1049    const float right = left + bitmap->width();
1050    const float bottom = top + bitmap->height();
1051
1052    if (quickReject(left, top, right, bottom)) {
1053        return;
1054    }
1055
1056    glActiveTexture(gTextureUnits[0]);
1057    Texture* texture = mCaches.textureCache.get(bitmap);
1058    if (!texture) return;
1059    const AutoTexture autoCleanup(texture);
1060
1061    drawTextureRect(left, top, right, bottom, texture, paint);
1062}
1063
1064void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1065    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1066    const mat4 transform(*matrix);
1067    transform.mapRect(r);
1068
1069    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1070        return;
1071    }
1072
1073    glActiveTexture(gTextureUnits[0]);
1074    Texture* texture = mCaches.textureCache.get(bitmap);
1075    if (!texture) return;
1076    const AutoTexture autoCleanup(texture);
1077
1078    // This could be done in a cheaper way, all we need is pass the matrix
1079    // to the vertex shader. The save/restore is a bit overkill.
1080    save(SkCanvas::kMatrix_SaveFlag);
1081    concatMatrix(matrix);
1082    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1083    restore();
1084}
1085
1086void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1087        float* vertices, int* colors, SkPaint* paint) {
1088    // TODO: Do a quickReject
1089    if (!vertices || mSnapshot->isIgnored()) {
1090        return;
1091    }
1092
1093    glActiveTexture(gTextureUnits[0]);
1094    Texture* texture = mCaches.textureCache.get(bitmap);
1095    if (!texture) return;
1096    const AutoTexture autoCleanup(texture);
1097    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1098
1099    int alpha;
1100    SkXfermode::Mode mode;
1101    getAlphaAndMode(paint, &alpha, &mode);
1102
1103    const uint32_t count = meshWidth * meshHeight * 6;
1104
1105    // TODO: Support the colors array
1106    TextureVertex mesh[count];
1107    TextureVertex* vertex = mesh;
1108    for (int32_t y = 0; y < meshHeight; y++) {
1109        for (int32_t x = 0; x < meshWidth; x++) {
1110            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1111
1112            float u1 = float(x) / meshWidth;
1113            float u2 = float(x + 1) / meshWidth;
1114            float v1 = float(y) / meshHeight;
1115            float v2 = float(y + 1) / meshHeight;
1116
1117            int ax = i + (meshWidth + 1) * 2;
1118            int ay = ax + 1;
1119            int bx = i;
1120            int by = bx + 1;
1121            int cx = i + 2;
1122            int cy = cx + 1;
1123            int dx = i + (meshWidth + 1) * 2 + 2;
1124            int dy = dx + 1;
1125
1126            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1127            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1128            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1129
1130            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1131            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1132            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1133        }
1134    }
1135
1136    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1137            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1138            GL_TRIANGLES, count);
1139}
1140
1141void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1142         float srcLeft, float srcTop, float srcRight, float srcBottom,
1143         float dstLeft, float dstTop, float dstRight, float dstBottom,
1144         SkPaint* paint) {
1145    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1146        return;
1147    }
1148
1149    glActiveTexture(gTextureUnits[0]);
1150    Texture* texture = mCaches.textureCache.get(bitmap);
1151    if (!texture) return;
1152    const AutoTexture autoCleanup(texture);
1153    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1154
1155    const float width = texture->width;
1156    const float height = texture->height;
1157
1158    const float u1 = srcLeft / width;
1159    const float v1 = srcTop / height;
1160    const float u2 = srcRight / width;
1161    const float v2 = srcBottom / height;
1162
1163    mCaches.unbindMeshBuffer();
1164    resetDrawTextureTexCoords(u1, v1, u2, v2);
1165
1166    int alpha;
1167    SkXfermode::Mode mode;
1168    getAlphaAndMode(paint, &alpha, &mode);
1169
1170    if (mSnapshot->transform->isPureTranslate()) {
1171        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1172        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1173
1174        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1175                texture->id, alpha / 255.0f, mode, texture->blend,
1176                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1177                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1178    } else {
1179        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1180                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1181                GL_TRIANGLE_STRIP, gMeshCount);
1182    }
1183
1184    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1185}
1186
1187void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1188        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1189        float left, float top, float right, float bottom, SkPaint* paint) {
1190    if (quickReject(left, top, right, bottom)) {
1191        return;
1192    }
1193
1194    glActiveTexture(gTextureUnits[0]);
1195    Texture* texture = mCaches.textureCache.get(bitmap);
1196    if (!texture) return;
1197    const AutoTexture autoCleanup(texture);
1198    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1199
1200    int alpha;
1201    SkXfermode::Mode mode;
1202    getAlphaAndMode(paint, &alpha, &mode);
1203
1204    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1205            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1206
1207    if (mesh && mesh->verticesCount > 0) {
1208        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1209#if RENDER_LAYERS_AS_REGIONS
1210        // Mark the current layer dirty where we are going to draw the patch
1211        if (hasLayer() && mesh->hasEmptyQuads) {
1212            const size_t count = mesh->quads.size();
1213            for (size_t i = 0; i < count; i++) {
1214                const Rect& bounds = mesh->quads.itemAt(i);
1215                if (pureTranslate) {
1216                    const float x = (int) floorf(bounds.left + 0.5f);
1217                    const float y = (int) floorf(bounds.top + 0.5f);
1218                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1219                            *mSnapshot->transform);
1220                } else {
1221                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1222                            *mSnapshot->transform);
1223                }
1224            }
1225        }
1226#endif
1227
1228        if (pureTranslate) {
1229            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1230            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1231
1232            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1233                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1234                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1235                    true, !mesh->hasEmptyQuads);
1236        } else {
1237            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1238                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1239                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1240                    true, !mesh->hasEmptyQuads);
1241        }
1242    }
1243}
1244
1245void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1246    if (mSnapshot->isIgnored()) return;
1247
1248    const bool isAA = paint->isAntiAlias();
1249    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1250    // A stroke width of 0 has a special meaningin Skia:
1251    // it draws an unscaled 1px wide line
1252    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1253
1254    int alpha;
1255    SkXfermode::Mode mode;
1256    getAlphaAndMode(paint, &alpha, &mode);
1257
1258    int verticesCount = count >> 2;
1259    int generatedVerticesCount = 0;
1260    if (!isHairLine) {
1261        // TODO: AA needs more vertices
1262        verticesCount *= 6;
1263    } else {
1264        // TODO: AA will be different
1265        verticesCount *= 2;
1266    }
1267
1268    TextureVertex lines[verticesCount];
1269    TextureVertex* vertex = &lines[0];
1270
1271    setupDraw();
1272    setupDrawColor(paint->getColor(), alpha);
1273    setupDrawColorFilter();
1274    setupDrawShader();
1275    setupDrawBlending(mode);
1276    setupDrawProgram();
1277    setupDrawModelViewIdentity();
1278    setupDrawColorUniforms();
1279    setupDrawColorFilterUniforms();
1280    setupDrawShaderIdentityUniforms();
1281    setupDrawMesh(vertex);
1282
1283    if (!isHairLine) {
1284        // TODO: Handle the AA case
1285        for (int i = 0; i < count; i += 4) {
1286            // a = start point, b = end point
1287            vec2 a(points[i], points[i + 1]);
1288            vec2 b(points[i + 2], points[i + 3]);
1289
1290            // Bias to snap to the same pixels as Skia
1291            a += 0.375;
1292            b += 0.375;
1293
1294            // Find the normal to the line
1295            vec2 n = (b - a).copyNormalized() * strokeWidth;
1296            float x = n.x;
1297            n.x = -n.y;
1298            n.y = x;
1299
1300            // Four corners of the rectangle defining a thick line
1301            vec2 p1 = a - n;
1302            vec2 p2 = a + n;
1303            vec2 p3 = b + n;
1304            vec2 p4 = b - n;
1305
1306            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1307            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1308            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1309            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1310
1311            if (!quickReject(left, top, right, bottom)) {
1312                // Draw the line as 2 triangles, could be optimized
1313                // by using only 4 vertices and the correct indices
1314                // Also we should probably used non textured vertices
1315                // when line AA is disabled to save on bandwidth
1316                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1317                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1318                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1319                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1320                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1321                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1322
1323                generatedVerticesCount += 6;
1324
1325                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1326            }
1327        }
1328
1329        if (generatedVerticesCount > 0) {
1330            // GL_LINE does not give the result we want to match Skia
1331            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1332        }
1333    } else {
1334        // TODO: Handle the AA case
1335        for (int i = 0; i < count; i += 4) {
1336            const float left = fmin(points[i], points[i + 1]);
1337            const float right = fmax(points[i], points[i + 1]);
1338            const float top = fmin(points[i + 2], points[i + 3]);
1339            const float bottom = fmax(points[i + 2], points[i + 3]);
1340
1341            if (!quickReject(left, top, right, bottom)) {
1342                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1343                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1344
1345                generatedVerticesCount += 2;
1346
1347                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1348            }
1349        }
1350
1351        if (generatedVerticesCount > 0) {
1352            glLineWidth(1.0f);
1353            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1354        }
1355    }
1356}
1357
1358void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1359    // No need to check against the clip, we fill the clip region
1360    if (mSnapshot->isIgnored()) return;
1361
1362    Rect& clip(*mSnapshot->clipRect);
1363    clip.snapToPixelBoundaries();
1364
1365    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1366}
1367
1368void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1369    if (!texture) return;
1370    const AutoTexture autoCleanup(texture);
1371
1372    const float x = left + texture->left - texture->offset;
1373    const float y = top + texture->top - texture->offset;
1374
1375    drawPathTexture(texture, x, y, paint);
1376}
1377
1378void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1379        float rx, float ry, SkPaint* paint) {
1380    if (mSnapshot->isIgnored()) return;
1381
1382    glActiveTexture(gTextureUnits[0]);
1383    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1384            right - left, bottom - top, rx, ry, paint);
1385    drawShape(left, top, texture, paint);
1386}
1387
1388void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1389    if (mSnapshot->isIgnored()) return;
1390
1391    glActiveTexture(gTextureUnits[0]);
1392    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1393    drawShape(x - radius, y - radius, texture, paint);
1394}
1395
1396void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1397    if (mSnapshot->isIgnored()) return;
1398
1399    glActiveTexture(gTextureUnits[0]);
1400    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1401    drawShape(left, top, texture, paint);
1402}
1403
1404void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1405        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1406    if (mSnapshot->isIgnored()) return;
1407
1408    if (fabs(sweepAngle) >= 360.0f) {
1409        drawOval(left, top, right, bottom, paint);
1410        return;
1411    }
1412
1413    glActiveTexture(gTextureUnits[0]);
1414    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1415            startAngle, sweepAngle, useCenter, paint);
1416    drawShape(left, top, texture, paint);
1417}
1418
1419void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1420        SkPaint* paint) {
1421    if (mSnapshot->isIgnored()) return;
1422
1423    glActiveTexture(gTextureUnits[0]);
1424    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1425    drawShape(left, top, texture, paint);
1426}
1427
1428void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1429    if (p->getStyle() != SkPaint::kFill_Style) {
1430        drawRectAsShape(left, top, right, bottom, p);
1431        return;
1432    }
1433
1434    if (quickReject(left, top, right, bottom)) {
1435        return;
1436    }
1437
1438    SkXfermode::Mode mode;
1439    if (!mCaches.extensions.hasFramebufferFetch()) {
1440        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1441        if (!isMode) {
1442            // Assume SRC_OVER
1443            mode = SkXfermode::kSrcOver_Mode;
1444        }
1445    } else {
1446        mode = getXfermode(p->getXfermode());
1447    }
1448
1449    int color = p->getColor();
1450    drawColorRect(left, top, right, bottom, color, mode);
1451}
1452
1453void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1454        float x, float y, SkPaint* paint) {
1455    if (text == NULL || count == 0) {
1456        return;
1457    }
1458    if (mSnapshot->isIgnored()) return;
1459
1460    paint->setAntiAlias(true);
1461
1462    float length = -1.0f;
1463    switch (paint->getTextAlign()) {
1464        case SkPaint::kCenter_Align:
1465            length = paint->measureText(text, bytesCount);
1466            x -= length / 2.0f;
1467            break;
1468        case SkPaint::kRight_Align:
1469            length = paint->measureText(text, bytesCount);
1470            x -= length;
1471            break;
1472        default:
1473            break;
1474    }
1475
1476    // TODO: Handle paint->getTextScaleX()
1477    const float oldX = x;
1478    const float oldY = y;
1479    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1480    if (pureTranslate) {
1481        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1482        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1483    }
1484
1485    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1486    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1487            paint->getTextSize());
1488
1489    int alpha;
1490    SkXfermode::Mode mode;
1491    getAlphaAndMode(paint, &alpha, &mode);
1492
1493    if (mHasShadow) {
1494        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1495        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1496                count, mShadowRadius);
1497        const AutoTexture autoCleanup(shadow);
1498
1499        const float sx = x - shadow->left + mShadowDx;
1500        const float sy = y - shadow->top + mShadowDy;
1501
1502        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1503
1504        glActiveTexture(gTextureUnits[0]);
1505        setupDraw();
1506        setupDrawWithTexture(true);
1507        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1508        setupDrawBlending(true, mode);
1509        setupDrawProgram();
1510        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1511        setupDrawTexture(shadow->id);
1512        setupDrawPureColorUniforms();
1513        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1514
1515        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1516        finishDrawTexture();
1517    }
1518
1519    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1520        return;
1521    }
1522
1523    // Pick the appropriate texture filtering
1524    bool linearFilter = mSnapshot->transform->changesBounds();
1525    if (pureTranslate && !linearFilter) {
1526        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1527    }
1528
1529    glActiveTexture(gTextureUnits[0]);
1530    setupDraw();
1531    setupDrawDirtyRegionsDisabled();
1532    setupDrawWithTexture(true);
1533    setupDrawAlpha8Color(paint->getColor(), alpha);
1534    setupDrawColorFilter();
1535    setupDrawShader();
1536    setupDrawBlending(true, mode);
1537    setupDrawProgram();
1538    setupDrawModelView(x, y, x, y, pureTranslate, true);
1539    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1540    setupDrawPureColorUniforms();
1541    setupDrawColorFilterUniforms();
1542    setupDrawShaderUniforms(pureTranslate);
1543
1544    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1545    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1546
1547#if RENDER_LAYERS_AS_REGIONS
1548    bool hasActiveLayer = hasLayer();
1549#else
1550    bool hasActiveLayer = false;
1551#endif
1552
1553    mCaches.unbindMeshBuffer();
1554    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1555            hasActiveLayer ? &bounds : NULL)) {
1556#if RENDER_LAYERS_AS_REGIONS
1557        if (hasActiveLayer) {
1558            if (!pureTranslate) {
1559                mSnapshot->transform->mapRect(bounds);
1560            }
1561            dirtyLayerUnchecked(bounds, getRegion());
1562        }
1563#endif
1564    }
1565
1566    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1567    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1568
1569    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1570}
1571
1572void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1573    if (mSnapshot->isIgnored()) return;
1574
1575    glActiveTexture(gTextureUnits[0]);
1576
1577    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1578    if (!texture) return;
1579    const AutoTexture autoCleanup(texture);
1580
1581    const float x = texture->left - texture->offset;
1582    const float y = texture->top - texture->offset;
1583
1584    drawPathTexture(texture, x, y, paint);
1585}
1586
1587void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1588    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1589        return;
1590    }
1591
1592    glActiveTexture(gTextureUnits[0]);
1593
1594    int alpha;
1595    SkXfermode::Mode mode;
1596    getAlphaAndMode(paint, &alpha, &mode);
1597
1598    layer->alpha = alpha;
1599    layer->mode = mode;
1600
1601#if RENDER_LAYERS_AS_REGIONS
1602    if (!layer->region.isEmpty()) {
1603        if (layer->region.isRect()) {
1604            const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1605            composeLayerRect(layer, r);
1606        } else if (layer->mesh) {
1607            const float a = alpha / 255.0f;
1608            const Rect& rect = layer->layer;
1609
1610            setupDraw();
1611            setupDrawWithTexture();
1612            setupDrawColor(a, a, a, a);
1613            setupDrawColorFilter();
1614            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1615            setupDrawProgram();
1616            setupDrawPureColorUniforms();
1617            setupDrawColorFilterUniforms();
1618            setupDrawTexture(layer->texture);
1619            // TODO: The current layer, if any, will be dirtied with the bounding box
1620            //       of the layer we are drawing. Since the layer we are drawing has
1621            //       a mesh, we know the dirty region, we should use it instead
1622            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1623            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1624
1625            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1626                    GL_UNSIGNED_SHORT, layer->meshIndices);
1627
1628            finishDrawTexture();
1629        }
1630    }
1631#else
1632    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1633    composeLayerRect(layer, r);
1634#endif
1635}
1636
1637///////////////////////////////////////////////////////////////////////////////
1638// Shaders
1639///////////////////////////////////////////////////////////////////////////////
1640
1641void OpenGLRenderer::resetShader() {
1642    mShader = NULL;
1643}
1644
1645void OpenGLRenderer::setupShader(SkiaShader* shader) {
1646    mShader = shader;
1647    if (mShader) {
1648        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1649    }
1650}
1651
1652///////////////////////////////////////////////////////////////////////////////
1653// Color filters
1654///////////////////////////////////////////////////////////////////////////////
1655
1656void OpenGLRenderer::resetColorFilter() {
1657    mColorFilter = NULL;
1658}
1659
1660void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1661    mColorFilter = filter;
1662}
1663
1664///////////////////////////////////////////////////////////////////////////////
1665// Drop shadow
1666///////////////////////////////////////////////////////////////////////////////
1667
1668void OpenGLRenderer::resetShadow() {
1669    mHasShadow = false;
1670}
1671
1672void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1673    mHasShadow = true;
1674    mShadowRadius = radius;
1675    mShadowDx = dx;
1676    mShadowDy = dy;
1677    mShadowColor = color;
1678}
1679
1680///////////////////////////////////////////////////////////////////////////////
1681// Drawing implementation
1682///////////////////////////////////////////////////////////////////////////////
1683
1684void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1685        float x, float y, SkPaint* paint) {
1686    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1687        return;
1688    }
1689
1690    int alpha;
1691    SkXfermode::Mode mode;
1692    getAlphaAndMode(paint, &alpha, &mode);
1693
1694    setupDraw();
1695    setupDrawWithTexture(true);
1696    setupDrawAlpha8Color(paint->getColor(), alpha);
1697    setupDrawColorFilter();
1698    setupDrawShader();
1699    setupDrawBlending(true, mode);
1700    setupDrawProgram();
1701    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1702    setupDrawTexture(texture->id);
1703    setupDrawPureColorUniforms();
1704    setupDrawColorFilterUniforms();
1705    setupDrawShaderUniforms();
1706    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1707
1708    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1709
1710    finishDrawTexture();
1711}
1712
1713// Same values used by Skia
1714#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1715#define kStdUnderline_Offset    (1.0f / 9.0f)
1716#define kStdUnderline_Thickness (1.0f / 18.0f)
1717
1718void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1719        float x, float y, SkPaint* paint) {
1720    // Handle underline and strike-through
1721    uint32_t flags = paint->getFlags();
1722    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1723        float underlineWidth = length;
1724        // If length is > 0.0f, we already measured the text for the text alignment
1725        if (length <= 0.0f) {
1726            underlineWidth = paint->measureText(text, bytesCount);
1727        }
1728
1729        float offsetX = 0;
1730        switch (paint->getTextAlign()) {
1731            case SkPaint::kCenter_Align:
1732                offsetX = underlineWidth * 0.5f;
1733                break;
1734            case SkPaint::kRight_Align:
1735                offsetX = underlineWidth;
1736                break;
1737            default:
1738                break;
1739        }
1740
1741        if (underlineWidth > 0.0f) {
1742            const float textSize = paint->getTextSize();
1743            // TODO: Support stroke width < 1.0f when we have AA lines
1744            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
1745
1746            const float left = x - offsetX;
1747            float top = 0.0f;
1748
1749            int linesCount = 0;
1750            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
1751            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
1752
1753            const int pointsCount = 4 * linesCount;
1754            float points[pointsCount];
1755            int currentPoint = 0;
1756
1757            if (flags & SkPaint::kUnderlineText_Flag) {
1758                top = y + textSize * kStdUnderline_Offset;
1759                points[currentPoint++] = left;
1760                points[currentPoint++] = top;
1761                points[currentPoint++] = left + underlineWidth;
1762                points[currentPoint++] = top;
1763            }
1764
1765            if (flags & SkPaint::kStrikeThruText_Flag) {
1766                top = y + textSize * kStdStrikeThru_Offset;
1767                points[currentPoint++] = left;
1768                points[currentPoint++] = top;
1769                points[currentPoint++] = left + underlineWidth;
1770                points[currentPoint++] = top;
1771            }
1772
1773            SkPaint linesPaint(*paint);
1774            linesPaint.setStrokeWidth(strokeWidth);
1775
1776            drawLines(&points[0], pointsCount, &linesPaint);
1777        }
1778    }
1779}
1780
1781void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1782        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1783    // If a shader is set, preserve only the alpha
1784    if (mShader) {
1785        color |= 0x00ffffff;
1786    }
1787
1788    setupDraw();
1789    setupDrawColor(color);
1790    setupDrawShader();
1791    setupDrawColorFilter();
1792    setupDrawBlending(mode);
1793    setupDrawProgram();
1794    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1795    setupDrawColorUniforms();
1796    setupDrawShaderUniforms(ignoreTransform);
1797    setupDrawColorFilterUniforms();
1798    setupDrawSimpleMesh();
1799
1800    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1801}
1802
1803void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1804        Texture* texture, SkPaint* paint) {
1805    int alpha;
1806    SkXfermode::Mode mode;
1807    getAlphaAndMode(paint, &alpha, &mode);
1808
1809    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1810
1811    if (mSnapshot->transform->isPureTranslate()) {
1812        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1813        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1814
1815        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1816                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1817                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1818    } else {
1819        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1820                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1821                GL_TRIANGLE_STRIP, gMeshCount);
1822    }
1823}
1824
1825void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1826        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1827    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1828            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1829}
1830
1831void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1832        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1833        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1834        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1835
1836    setupDraw();
1837    setupDrawWithTexture();
1838    setupDrawColor(alpha, alpha, alpha, alpha);
1839    setupDrawColorFilter();
1840    setupDrawBlending(blend, mode, swapSrcDst);
1841    setupDrawProgram();
1842    if (!dirty) {
1843        setupDrawDirtyRegionsDisabled();
1844    }
1845    if (!ignoreScale) {
1846        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1847    } else {
1848        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1849    }
1850    setupDrawPureColorUniforms();
1851    setupDrawColorFilterUniforms();
1852    setupDrawTexture(texture);
1853    setupDrawMesh(vertices, texCoords, vbo);
1854
1855    glDrawArrays(drawMode, 0, elementsCount);
1856
1857    finishDrawTexture();
1858}
1859
1860void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1861        ProgramDescription& description, bool swapSrcDst) {
1862    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1863    if (blend) {
1864        if (mode < SkXfermode::kPlus_Mode) {
1865            if (!mCaches.blend) {
1866                glEnable(GL_BLEND);
1867            }
1868
1869            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1870            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1871
1872            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1873                glBlendFunc(sourceMode, destMode);
1874                mCaches.lastSrcMode = sourceMode;
1875                mCaches.lastDstMode = destMode;
1876            }
1877        } else {
1878            // These blend modes are not supported by OpenGL directly and have
1879            // to be implemented using shaders. Since the shader will perform
1880            // the blending, turn blending off here
1881            if (mCaches.extensions.hasFramebufferFetch()) {
1882                description.framebufferMode = mode;
1883                description.swapSrcDst = swapSrcDst;
1884            }
1885
1886            if (mCaches.blend) {
1887                glDisable(GL_BLEND);
1888            }
1889            blend = false;
1890        }
1891    } else if (mCaches.blend) {
1892        glDisable(GL_BLEND);
1893    }
1894    mCaches.blend = blend;
1895}
1896
1897bool OpenGLRenderer::useProgram(Program* program) {
1898    if (!program->isInUse()) {
1899        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1900        program->use();
1901        mCaches.currentProgram = program;
1902        return false;
1903    }
1904    return true;
1905}
1906
1907void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1908    TextureVertex* v = &mMeshVertices[0];
1909    TextureVertex::setUV(v++, u1, v1);
1910    TextureVertex::setUV(v++, u2, v1);
1911    TextureVertex::setUV(v++, u1, v2);
1912    TextureVertex::setUV(v++, u2, v2);
1913}
1914
1915void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1916    if (paint) {
1917        if (!mCaches.extensions.hasFramebufferFetch()) {
1918            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1919            if (!isMode) {
1920                // Assume SRC_OVER
1921                *mode = SkXfermode::kSrcOver_Mode;
1922            }
1923        } else {
1924            *mode = getXfermode(paint->getXfermode());
1925        }
1926
1927        // Skia draws using the color's alpha channel if < 255
1928        // Otherwise, it uses the paint's alpha
1929        int color = paint->getColor();
1930        *alpha = (color >> 24) & 0xFF;
1931        if (*alpha == 255) {
1932            *alpha = paint->getAlpha();
1933        }
1934    } else {
1935        *mode = SkXfermode::kSrcOver_Mode;
1936        *alpha = 255;
1937    }
1938}
1939
1940SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1941    if (mode == NULL) {
1942        return SkXfermode::kSrcOver_Mode;
1943    }
1944    return mode->fMode;
1945}
1946
1947void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1948    bool bound = false;
1949    if (wrapS != texture->wrapS) {
1950        glBindTexture(GL_TEXTURE_2D, texture->id);
1951        bound = true;
1952        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1953        texture->wrapS = wrapS;
1954    }
1955    if (wrapT != texture->wrapT) {
1956        if (!bound) {
1957            glBindTexture(GL_TEXTURE_2D, texture->id);
1958        }
1959        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1960        texture->wrapT = wrapT;
1961    }
1962}
1963
1964}; // namespace uirenderer
1965}; // namespace android
1966