OpenGLRenderer.cpp revision 08aa2cbd5e62e7ca140f78f8bea0477a19880fd9 
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 <private/hwui/DrawGlInfo.h>
30
31#include <ui/Rect.h>
32
33#include "OpenGLRenderer.h"
34#include "DisplayListRenderer.h"
35#include "Vector.h"
36
37namespace android {
38namespace uirenderer {
39
40///////////////////////////////////////////////////////////////////////////////
41// Defines
42///////////////////////////////////////////////////////////////////////////////
43
44#define RAD_TO_DEG (180.0f / 3.14159265f)
45#define MIN_ANGLE 0.001f
46
47// TODO: This should be set in properties
48#define ALPHA_THRESHOLD (0x7f / PANEL_BIT_DEPTH)
49
50///////////////////////////////////////////////////////////////////////////////
51// Globals
52///////////////////////////////////////////////////////////////////////////////
53
54/**
55 * Structure mapping Skia xfermodes to OpenGL blending factors.
56 */
57struct Blender {
58    SkXfermode::Mode mode;
59    GLenum src;
60    GLenum dst;
61}; // struct Blender
62
63// In this array, the index of each Blender equals the value of the first
64// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
65static const Blender gBlends[] = {
66    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
67    { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
68    { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
69    { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
70    { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
71    { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
72    { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
73    { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
74    { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
75    { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
76    { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
77    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
78};
79
80// This array contains the swapped version of each SkXfermode. For instance
81// this array's SrcOver blending mode is actually DstOver. You can refer to
82// createLayer() for more information on the purpose of this array.
83static const Blender gBlendsSwap[] = {
84    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
85    { SkXfermode::kSrc_Mode,     GL_ZERO,                 GL_ONE },
86    { SkXfermode::kDst_Mode,     GL_ONE,                  GL_ZERO },
87    { SkXfermode::kSrcOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
88    { SkXfermode::kDstOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
89    { SkXfermode::kSrcIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
90    { SkXfermode::kDstIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
91    { SkXfermode::kSrcOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
92    { SkXfermode::kDstOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
93    { SkXfermode::kSrcATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
94    { SkXfermode::kDstATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
95    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
96};
97
98static const GLenum gTextureUnits[] = {
99    GL_TEXTURE0,
100    GL_TEXTURE1,
101    GL_TEXTURE2
102};
103
104///////////////////////////////////////////////////////////////////////////////
105// Constructors/destructor
106///////////////////////////////////////////////////////////////////////////////
107
108OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
109    mShader = NULL;
110    mColorFilter = NULL;
111    mHasShadow = false;
112
113    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
114
115    mFirstSnapshot = new Snapshot;
116}
117
118OpenGLRenderer::~OpenGLRenderer() {
119    // The context has already been destroyed at this point, do not call
120    // GL APIs. All GL state should be kept in Caches.h
121}
122
123///////////////////////////////////////////////////////////////////////////////
124// Setup
125///////////////////////////////////////////////////////////////////////////////
126
127void OpenGLRenderer::setViewport(int width, int height) {
128    glViewport(0, 0, width, height);
129    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
130
131    mWidth = width;
132    mHeight = height;
133
134    mFirstSnapshot->height = height;
135    mFirstSnapshot->viewport.set(0, 0, width, height);
136
137    mDirtyClip = false;
138}
139
140void OpenGLRenderer::prepare(bool opaque) {
141    prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
142}
143
144void OpenGLRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
145    mCaches.clearGarbage();
146
147    mSnapshot = new Snapshot(mFirstSnapshot,
148            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
149    mSnapshot->fbo = getTargetFbo();
150
151    mSaveCount = 1;
152
153    glViewport(0, 0, mWidth, mHeight);
154
155    glDisable(GL_DITHER);
156
157    glEnable(GL_SCISSOR_TEST);
158    glScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
159    mSnapshot->setClip(left, top, right, bottom);
160
161    if (!opaque) {
162        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
163        glClear(GL_COLOR_BUFFER_BIT);
164    }
165}
166
167void OpenGLRenderer::finish() {
168#if DEBUG_OPENGL
169    GLenum status = GL_NO_ERROR;
170    while ((status = glGetError()) != GL_NO_ERROR) {
171        LOGD("GL error from OpenGLRenderer: 0x%x", status);
172        switch (status) {
173            case GL_OUT_OF_MEMORY:
174                LOGE("  OpenGLRenderer is out of memory!");
175                break;
176        }
177    }
178#endif
179#if DEBUG_MEMORY_USAGE
180    mCaches.dumpMemoryUsage();
181#else
182    if (mCaches.getDebugLevel() & kDebugMemory) {
183        mCaches.dumpMemoryUsage();
184    }
185#endif
186}
187
188void OpenGLRenderer::interrupt() {
189    if (mCaches.currentProgram) {
190        if (mCaches.currentProgram->isInUse()) {
191            mCaches.currentProgram->remove();
192            mCaches.currentProgram = NULL;
193        }
194    }
195    mCaches.unbindMeshBuffer();
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
215bool OpenGLRenderer::callDrawGLFunction(Functor *functor, Rect& dirty) {
216    interrupt();
217    if (mDirtyClip) {
218        setScissorFromClip();
219    }
220
221    Rect clip(*mSnapshot->clipRect);
222    clip.snapToPixelBoundaries();
223
224#if RENDER_LAYERS_AS_REGIONS
225    // Since we don't know what the functor will draw, let's dirty
226    // tne entire clip region
227    if (hasLayer()) {
228        dirtyLayerUnchecked(clip, getRegion());
229    }
230#endif
231
232    DrawGlInfo info;
233    info.clipLeft = clip.left;
234    info.clipTop = clip.top;
235    info.clipRight = clip.right;
236    info.clipBottom = clip.bottom;
237    info.isLayer = hasLayer();
238    getSnapshot()->transform->copyTo(&info.transform[0]);
239
240    status_t result = (*functor)(0, &info);
241
242    if (result != 0) {
243        Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
244        dirty.unionWith(localDirty);
245    }
246
247    resume();
248    return result != 0;
249}
250
251///////////////////////////////////////////////////////////////////////////////
252// State management
253///////////////////////////////////////////////////////////////////////////////
254
255int OpenGLRenderer::getSaveCount() const {
256    return mSaveCount;
257}
258
259int OpenGLRenderer::save(int flags) {
260    return saveSnapshot(flags);
261}
262
263void OpenGLRenderer::restore() {
264    if (mSaveCount > 1) {
265        restoreSnapshot();
266    }
267}
268
269void OpenGLRenderer::restoreToCount(int saveCount) {
270    if (saveCount < 1) saveCount = 1;
271
272    while (mSaveCount > saveCount) {
273        restoreSnapshot();
274    }
275}
276
277int OpenGLRenderer::saveSnapshot(int flags) {
278    mSnapshot = new Snapshot(mSnapshot, flags);
279    return mSaveCount++;
280}
281
282bool OpenGLRenderer::restoreSnapshot() {
283    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
284    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
285    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
286
287    sp<Snapshot> current = mSnapshot;
288    sp<Snapshot> previous = mSnapshot->previous;
289
290    if (restoreOrtho) {
291        Rect& r = previous->viewport;
292        glViewport(r.left, r.top, r.right, r.bottom);
293        mOrthoMatrix.load(current->orthoMatrix);
294    }
295
296    mSaveCount--;
297    mSnapshot = previous;
298
299    if (restoreClip) {
300        dirtyClip();
301    }
302
303    if (restoreLayer) {
304        composeLayer(current, previous);
305    }
306
307    return restoreClip;
308}
309
310///////////////////////////////////////////////////////////////////////////////
311// Layers
312///////////////////////////////////////////////////////////////////////////////
313
314int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
315        SkPaint* p, int flags) {
316    const GLuint previousFbo = mSnapshot->fbo;
317    const int count = saveSnapshot(flags);
318
319    if (!mSnapshot->isIgnored()) {
320        int alpha = 255;
321        SkXfermode::Mode mode;
322
323        if (p) {
324            alpha = p->getAlpha();
325            if (!mCaches.extensions.hasFramebufferFetch()) {
326                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
327                if (!isMode) {
328                    // Assume SRC_OVER
329                    mode = SkXfermode::kSrcOver_Mode;
330                }
331            } else {
332                mode = getXfermode(p->getXfermode());
333            }
334        } else {
335            mode = SkXfermode::kSrcOver_Mode;
336        }
337
338        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
339    }
340
341    return count;
342}
343
344int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
345        int alpha, int flags) {
346    if (alpha >= 255 - ALPHA_THRESHOLD) {
347        return saveLayer(left, top, right, bottom, NULL, flags);
348    } else {
349        SkPaint paint;
350        paint.setAlpha(alpha);
351        return saveLayer(left, top, right, bottom, &paint, flags);
352    }
353}
354
355/**
356 * Layers are viewed by Skia are slightly different than layers in image editing
357 * programs (for instance.) When a layer is created, previously created layers
358 * and the frame buffer still receive every drawing command. For instance, if a
359 * layer is created and a shape intersecting the bounds of the layers and the
360 * framebuffer is draw, the shape will be drawn on both (unless the layer was
361 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
362 *
363 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
364 * texture. Unfortunately, this is inefficient as it requires every primitive to
365 * be drawn n + 1 times, where n is the number of active layers. In practice this
366 * means, for every primitive:
367 *   - Switch active frame buffer
368 *   - Change viewport, clip and projection matrix
369 *   - Issue the drawing
370 *
371 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
372 * To avoid this, layers are implemented in a different way here, at least in the
373 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
374 * is set. When this flag is set we can redirect all drawing operations into a
375 * single FBO.
376 *
377 * This implementation relies on the frame buffer being at least RGBA 8888. When
378 * a layer is created, only a texture is created, not an FBO. The content of the
379 * frame buffer contained within the layer's bounds is copied into this texture
380 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
381 * buffer and drawing continues as normal. This technique therefore treats the
382 * frame buffer as a scratch buffer for the layers.
383 *
384 * To compose the layers back onto the frame buffer, each layer texture
385 * (containing the original frame buffer data) is drawn as a simple quad over
386 * the frame buffer. The trick is that the quad is set as the composition
387 * destination in the blending equation, and the frame buffer becomes the source
388 * of the composition.
389 *
390 * Drawing layers with an alpha value requires an extra step before composition.
391 * An empty quad is drawn over the layer's region in the frame buffer. This quad
392 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
393 * quad is used to multiply the colors in the frame buffer. This is achieved by
394 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
395 * GL_ZERO, GL_SRC_ALPHA.
396 *
397 * Because glCopyTexImage2D() can be slow, an alternative implementation might
398 * be use to draw a single clipped layer. The implementation described above
399 * is correct in every case.
400 *
401 * (1) The frame buffer is actually not cleared right away. To allow the GPU
402 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
403 *     buffer is left untouched until the first drawing operation. Only when
404 *     something actually gets drawn are the layers regions cleared.
405 */
406bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
407        float right, float bottom, int alpha, SkXfermode::Mode mode,
408        int flags, GLuint previousFbo) {
409    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
410    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
411
412    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
413
414    // Window coordinates of the layer
415    Rect bounds(left, top, right, bottom);
416    if (!fboLayer) {
417        mSnapshot->transform->mapRect(bounds);
418
419        // Layers only make sense if they are in the framebuffer's bounds
420        if (bounds.intersect(*snapshot->clipRect)) {
421            // We cannot work with sub-pixels in this case
422            bounds.snapToPixelBoundaries();
423
424            // When the layer is not an FBO, we may use glCopyTexImage so we
425            // need to make sure the layer does not extend outside the bounds
426            // of the framebuffer
427            if (!bounds.intersect(snapshot->previous->viewport)) {
428                bounds.setEmpty();
429            }
430        } else {
431            bounds.setEmpty();
432        }
433    }
434
435    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
436            bounds.getHeight() > mCaches.maxTextureSize) {
437        snapshot->empty = fboLayer;
438    } else {
439        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
440    }
441
442    // Bail out if we won't draw in this snapshot
443    if (snapshot->invisible || snapshot->empty) {
444        return false;
445    }
446
447    glActiveTexture(gTextureUnits[0]);
448    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
449    if (!layer) {
450        return false;
451    }
452
453    layer->mode = mode;
454    layer->alpha = alpha;
455    layer->layer.set(bounds);
456    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
457            bounds.getWidth() / float(layer->width), 0.0f);
458    layer->colorFilter = mColorFilter;
459
460    // Save the layer in the snapshot
461    snapshot->flags |= Snapshot::kFlagIsLayer;
462    snapshot->layer = layer;
463
464    if (fboLayer) {
465        return createFboLayer(layer, bounds, snapshot, previousFbo);
466    } else {
467        // Copy the framebuffer into the layer
468        glBindTexture(GL_TEXTURE_2D, layer->texture);
469        if (!bounds.isEmpty()) {
470            if (layer->empty) {
471                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
472                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
473                layer->empty = false;
474            } else {
475                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
476                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
477            }
478
479            // Clear the framebuffer where the layer will draw
480            glScissor(bounds.left, mSnapshot->height - bounds.bottom,
481                    bounds.getWidth(), bounds.getHeight());
482            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
483            glClear(GL_COLOR_BUFFER_BIT);
484
485            dirtyClip();
486        }
487    }
488
489    return true;
490}
491
492bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
493        GLuint previousFbo) {
494    layer->fbo = mCaches.fboCache.get();
495
496#if RENDER_LAYERS_AS_REGIONS
497    snapshot->region = &snapshot->layer->region;
498    snapshot->flags |= Snapshot::kFlagFboTarget;
499#endif
500
501    Rect clip(bounds);
502    snapshot->transform->mapRect(clip);
503    clip.intersect(*snapshot->clipRect);
504    clip.snapToPixelBoundaries();
505    clip.intersect(snapshot->previous->viewport);
506
507    mat4 inverse;
508    inverse.loadInverse(*mSnapshot->transform);
509
510    inverse.mapRect(clip);
511    clip.snapToPixelBoundaries();
512    clip.intersect(bounds);
513    clip.translate(-bounds.left, -bounds.top);
514
515    snapshot->flags |= Snapshot::kFlagIsFboLayer;
516    snapshot->fbo = layer->fbo;
517    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
518    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
519    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
520    snapshot->height = bounds.getHeight();
521    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
522    snapshot->orthoMatrix.load(mOrthoMatrix);
523
524    // Bind texture to FBO
525    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
526    glBindTexture(GL_TEXTURE_2D, layer->texture);
527
528    // Initialize the texture if needed
529    if (layer->empty) {
530        layer->empty = false;
531        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
532                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
533    }
534
535    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
536            layer->texture, 0);
537
538#if DEBUG_LAYERS_AS_REGIONS
539    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
540    if (status != GL_FRAMEBUFFER_COMPLETE) {
541        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
542
543        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
544        glDeleteTextures(1, &layer->texture);
545        mCaches.fboCache.put(layer->fbo);
546
547        delete layer;
548
549        return false;
550    }
551#endif
552
553    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
554    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
555            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
556    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
557    glClear(GL_COLOR_BUFFER_BIT);
558
559    dirtyClip();
560
561    // Change the ortho projection
562    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
563    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
564
565    return true;
566}
567
568/**
569 * Read the documentation of createLayer() before doing anything in this method.
570 */
571void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
572    if (!current->layer) {
573        LOGE("Attempting to compose a layer that does not exist");
574        return;
575    }
576
577    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
578
579    if (fboLayer) {
580        // Unbind current FBO and restore previous one
581        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
582    }
583
584    Layer* layer = current->layer;
585    const Rect& rect = layer->layer;
586
587    if (!fboLayer && layer->alpha < 255) {
588        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
589                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
590        // Required below, composeLayerRect() will divide by 255
591        layer->alpha = 255;
592    }
593
594    mCaches.unbindMeshBuffer();
595
596    glActiveTexture(gTextureUnits[0]);
597
598    // When the layer is stored in an FBO, we can save a bit of fillrate by
599    // drawing only the dirty region
600    if (fboLayer) {
601        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
602        if (layer->colorFilter) {
603            setupColorFilter(layer->colorFilter);
604        }
605        composeLayerRegion(layer, rect);
606        if (layer->colorFilter) {
607            resetColorFilter();
608        }
609    } else {
610        if (!rect.isEmpty()) {
611            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
612            composeLayerRect(layer, rect, true);
613        }
614    }
615
616    if (fboLayer) {
617        // Detach the texture from the FBO
618        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
619        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
620        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
621
622        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
623        mCaches.fboCache.put(current->fbo);
624    }
625
626    dirtyClip();
627
628    // Failing to add the layer to the cache should happen only if the layer is too large
629    if (!mCaches.layerCache.put(layer)) {
630        LAYER_LOGD("Deleting layer");
631        glDeleteTextures(1, &layer->texture);
632        delete layer;
633    }
634}
635
636void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
637    const Rect& texCoords = layer->texCoords;
638    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
639
640    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
641            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
642            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
643
644    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
645}
646
647void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
648#if RENDER_LAYERS_AS_REGIONS
649#if RENDER_LAYERS_RECT_AS_RECT
650    if (layer->region.isRect()) {
651        composeLayerRect(layer, rect);
652        layer->region.clear();
653        return;
654    }
655#endif
656
657    if (!layer->region.isEmpty()) {
658        size_t count;
659        const android::Rect* rects = layer->region.getArray(&count);
660
661        const float alpha = layer->alpha / 255.0f;
662        const float texX = 1.0f / float(layer->width);
663        const float texY = 1.0f / float(layer->height);
664        const float height = rect.getHeight();
665
666        TextureVertex* mesh = mCaches.getRegionMesh();
667        GLsizei numQuads = 0;
668
669        setupDraw();
670        setupDrawWithTexture();
671        setupDrawColor(alpha, alpha, alpha, alpha);
672        setupDrawColorFilter();
673        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
674        setupDrawProgram();
675        setupDrawDirtyRegionsDisabled();
676        setupDrawPureColorUniforms();
677        setupDrawColorFilterUniforms();
678        setupDrawTexture(layer->texture);
679        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
680        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
681
682        for (size_t i = 0; i < count; i++) {
683            const android::Rect* r = &rects[i];
684
685            const float u1 = r->left * texX;
686            const float v1 = (height - r->top) * texY;
687            const float u2 = r->right * texX;
688            const float v2 = (height - r->bottom) * texY;
689
690            // TODO: Reject quads outside of the clip
691            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
692            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
693            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
694            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
695
696            numQuads++;
697
698            if (numQuads >= REGION_MESH_QUAD_COUNT) {
699                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
700                numQuads = 0;
701                mesh = mCaches.getRegionMesh();
702            }
703        }
704
705        if (numQuads > 0) {
706            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
707        }
708
709        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
710        finishDrawTexture();
711
712#if DEBUG_LAYERS_AS_REGIONS
713        drawRegionRects(layer->region);
714#endif
715
716        layer->region.clear();
717    }
718#else
719    composeLayerRect(layer, rect);
720#endif
721}
722
723void OpenGLRenderer::drawRegionRects(const Region& region) {
724#if DEBUG_LAYERS_AS_REGIONS
725    size_t count;
726    const android::Rect* rects = region.getArray(&count);
727
728    uint32_t colors[] = {
729            0x7fff0000, 0x7f00ff00,
730            0x7f0000ff, 0x7fff00ff,
731    };
732
733    int offset = 0;
734    int32_t top = rects[0].top;
735
736    for (size_t i = 0; i < count; i++) {
737        if (top != rects[i].top) {
738            offset ^= 0x2;
739            top = rects[i].top;
740        }
741
742        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
743        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
744                SkXfermode::kSrcOver_Mode);
745    }
746#endif
747}
748
749void OpenGLRenderer::dirtyLayer(const float left, const float top,
750        const float right, const float bottom, const mat4 transform) {
751#if RENDER_LAYERS_AS_REGIONS
752    if (hasLayer()) {
753        Rect bounds(left, top, right, bottom);
754        transform.mapRect(bounds);
755        dirtyLayerUnchecked(bounds, getRegion());
756    }
757#endif
758}
759
760void OpenGLRenderer::dirtyLayer(const float left, const float top,
761        const float right, const float bottom) {
762#if RENDER_LAYERS_AS_REGIONS
763    if (hasLayer()) {
764        Rect bounds(left, top, right, bottom);
765        dirtyLayerUnchecked(bounds, getRegion());
766    }
767#endif
768}
769
770void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
771#if RENDER_LAYERS_AS_REGIONS
772    if (bounds.intersect(*mSnapshot->clipRect)) {
773        bounds.snapToPixelBoundaries();
774        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
775        if (!dirty.isEmpty()) {
776            region->orSelf(dirty);
777        }
778    }
779#endif
780}
781
782///////////////////////////////////////////////////////////////////////////////
783// Transforms
784///////////////////////////////////////////////////////////////////////////////
785
786void OpenGLRenderer::translate(float dx, float dy) {
787    mSnapshot->transform->translate(dx, dy, 0.0f);
788}
789
790void OpenGLRenderer::rotate(float degrees) {
791    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
792}
793
794void OpenGLRenderer::scale(float sx, float sy) {
795    mSnapshot->transform->scale(sx, sy, 1.0f);
796}
797
798void OpenGLRenderer::skew(float sx, float sy) {
799    mSnapshot->transform->skew(sx, sy);
800}
801
802void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
803    mSnapshot->transform->load(*matrix);
804}
805
806const float* OpenGLRenderer::getMatrix() const {
807    if (mSnapshot->fbo != 0) {
808        return &mSnapshot->transform->data[0];
809    }
810    return &mIdentity.data[0];
811}
812
813void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
814    mSnapshot->transform->copyTo(*matrix);
815}
816
817void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
818    SkMatrix transform;
819    mSnapshot->transform->copyTo(transform);
820    transform.preConcat(*matrix);
821    mSnapshot->transform->load(transform);
822}
823
824///////////////////////////////////////////////////////////////////////////////
825// Clipping
826///////////////////////////////////////////////////////////////////////////////
827
828void OpenGLRenderer::setScissorFromClip() {
829    Rect clip(*mSnapshot->clipRect);
830    clip.snapToPixelBoundaries();
831    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
832    mDirtyClip = false;
833}
834
835const Rect& OpenGLRenderer::getClipBounds() {
836    return mSnapshot->getLocalClip();
837}
838
839bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
840    if (mSnapshot->isIgnored()) {
841        return true;
842    }
843
844    Rect r(left, top, right, bottom);
845    mSnapshot->transform->mapRect(r);
846    r.snapToPixelBoundaries();
847
848    Rect clipRect(*mSnapshot->clipRect);
849    clipRect.snapToPixelBoundaries();
850
851    return !clipRect.intersects(r);
852}
853
854bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
855    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
856    if (clipped) {
857        dirtyClip();
858    }
859    return !mSnapshot->clipRect->isEmpty();
860}
861
862///////////////////////////////////////////////////////////////////////////////
863// Drawing commands
864///////////////////////////////////////////////////////////////////////////////
865
866void OpenGLRenderer::setupDraw() {
867    if (mDirtyClip) {
868        setScissorFromClip();
869    }
870    mDescription.reset();
871    mSetShaderColor = false;
872    mColorSet = false;
873    mColorA = mColorR = mColorG = mColorB = 0.0f;
874    mTextureUnit = 0;
875    mTrackDirtyRegions = true;
876    mTexCoordsSlot = -1;
877}
878
879void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
880    mDescription.hasTexture = true;
881    mDescription.hasAlpha8Texture = isAlpha8;
882}
883
884void OpenGLRenderer::setupDrawColor(int color) {
885    setupDrawColor(color, (color >> 24) & 0xFF);
886}
887
888void OpenGLRenderer::setupDrawColor(int color, int alpha) {
889    mColorA = alpha / 255.0f;
890    const float a = mColorA / 255.0f;
891    mColorR = a * ((color >> 16) & 0xFF);
892    mColorG = a * ((color >>  8) & 0xFF);
893    mColorB = a * ((color      ) & 0xFF);
894    mColorSet = true;
895    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
896}
897
898void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
899    mColorA = alpha / 255.0f;
900    const float a = mColorA / 255.0f;
901    mColorR = a * ((color >> 16) & 0xFF);
902    mColorG = a * ((color >>  8) & 0xFF);
903    mColorB = a * ((color      ) & 0xFF);
904    mColorSet = true;
905    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
906}
907
908void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
909    mColorA = a;
910    mColorR = r;
911    mColorG = g;
912    mColorB = b;
913    mColorSet = true;
914    mSetShaderColor = mDescription.setColor(r, g, b, a);
915}
916
917void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
918    mColorA = a;
919    mColorR = r;
920    mColorG = g;
921    mColorB = b;
922    mColorSet = true;
923    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
924}
925
926void OpenGLRenderer::setupDrawShader() {
927    if (mShader) {
928        mShader->describe(mDescription, mCaches.extensions);
929    }
930}
931
932void OpenGLRenderer::setupDrawColorFilter() {
933    if (mColorFilter) {
934        mColorFilter->describe(mDescription, mCaches.extensions);
935    }
936}
937
938void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
939    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
940            mDescription, swapSrcDst);
941}
942
943void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
944    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
945            mDescription, swapSrcDst);
946}
947
948void OpenGLRenderer::setupDrawProgram() {
949    useProgram(mCaches.programCache.get(mDescription));
950}
951
952void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
953    mTrackDirtyRegions = false;
954}
955
956void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
957        bool ignoreTransform) {
958    mModelView.loadTranslate(left, top, 0.0f);
959    if (!ignoreTransform) {
960        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
961        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
962    } else {
963        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
964        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
965    }
966}
967
968void OpenGLRenderer::setupDrawModelViewIdentity() {
969    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
970}
971
972void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
973        bool ignoreTransform, bool ignoreModelView) {
974    if (!ignoreModelView) {
975        mModelView.loadTranslate(left, top, 0.0f);
976        mModelView.scale(right - left, bottom - top, 1.0f);
977    } else {
978        mModelView.loadIdentity();
979    }
980    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
981    if (!ignoreTransform) {
982        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
983        if (mTrackDirtyRegions && dirty) {
984            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
985        }
986    } else {
987        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
988        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
989    }
990}
991
992void OpenGLRenderer::setupDrawColorUniforms() {
993    if (mColorSet || (mShader && mSetShaderColor)) {
994        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
995    }
996}
997
998void OpenGLRenderer::setupDrawPureColorUniforms() {
999    if (mSetShaderColor) {
1000        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1001    }
1002}
1003
1004void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1005    if (mShader) {
1006        if (ignoreTransform) {
1007            mModelView.loadInverse(*mSnapshot->transform);
1008        }
1009        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
1010    }
1011}
1012
1013void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1014    if (mShader) {
1015        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1016    }
1017}
1018
1019void OpenGLRenderer::setupDrawColorFilterUniforms() {
1020    if (mColorFilter) {
1021        mColorFilter->setupProgram(mCaches.currentProgram);
1022    }
1023}
1024
1025void OpenGLRenderer::setupDrawSimpleMesh() {
1026    mCaches.bindMeshBuffer();
1027    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1028            gMeshStride, 0);
1029}
1030
1031void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1032    bindTexture(texture);
1033    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1034
1035    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1036    glEnableVertexAttribArray(mTexCoordsSlot);
1037}
1038
1039void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1040    if (!vertices) {
1041        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1042    } else {
1043        mCaches.unbindMeshBuffer();
1044    }
1045    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1046            gMeshStride, vertices);
1047    if (mTexCoordsSlot >= 0) {
1048        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1049    }
1050}
1051
1052void OpenGLRenderer::finishDrawTexture() {
1053    glDisableVertexAttribArray(mTexCoordsSlot);
1054}
1055
1056///////////////////////////////////////////////////////////////////////////////
1057// Drawing
1058///////////////////////////////////////////////////////////////////////////////
1059
1060bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t width, uint32_t height,
1061        Rect& dirty, uint32_t level) {
1062    if (quickReject(0.0f, 0.0f, width, height)) {
1063        return false;
1064    }
1065
1066    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1067    // will be performed by the display list itself
1068    if (displayList) {
1069        return displayList->replay(*this, dirty, level);
1070    }
1071
1072    return false;
1073}
1074
1075void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1076    const float right = left + bitmap->width();
1077    const float bottom = top + bitmap->height();
1078
1079    if (quickReject(left, top, right, bottom)) {
1080        return;
1081    }
1082
1083    glActiveTexture(gTextureUnits[0]);
1084    Texture* texture = mCaches.textureCache.get(bitmap);
1085    if (!texture) return;
1086    const AutoTexture autoCleanup(texture);
1087
1088    drawTextureRect(left, top, right, bottom, texture, paint);
1089}
1090
1091void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1092    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1093    const mat4 transform(*matrix);
1094    transform.mapRect(r);
1095
1096    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1097        return;
1098    }
1099
1100    glActiveTexture(gTextureUnits[0]);
1101    Texture* texture = mCaches.textureCache.get(bitmap);
1102    if (!texture) return;
1103    const AutoTexture autoCleanup(texture);
1104
1105    // This could be done in a cheaper way, all we need is pass the matrix
1106    // to the vertex shader. The save/restore is a bit overkill.
1107    save(SkCanvas::kMatrix_SaveFlag);
1108    concatMatrix(matrix);
1109    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1110    restore();
1111}
1112
1113void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1114        float* vertices, int* colors, SkPaint* paint) {
1115    // TODO: Do a quickReject
1116    if (!vertices || mSnapshot->isIgnored()) {
1117        return;
1118    }
1119
1120    glActiveTexture(gTextureUnits[0]);
1121    Texture* texture = mCaches.textureCache.get(bitmap);
1122    if (!texture) return;
1123    const AutoTexture autoCleanup(texture);
1124    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1125
1126    int alpha;
1127    SkXfermode::Mode mode;
1128    getAlphaAndMode(paint, &alpha, &mode);
1129
1130    const uint32_t count = meshWidth * meshHeight * 6;
1131
1132    float left = FLT_MAX;
1133    float top = FLT_MAX;
1134    float right = FLT_MIN;
1135    float bottom = FLT_MIN;
1136
1137#if RENDER_LAYERS_AS_REGIONS
1138    bool hasActiveLayer = hasLayer();
1139#else
1140    bool hasActiveLayer = false;
1141#endif
1142
1143    // TODO: Support the colors array
1144    TextureVertex mesh[count];
1145    TextureVertex* vertex = mesh;
1146    for (int32_t y = 0; y < meshHeight; y++) {
1147        for (int32_t x = 0; x < meshWidth; x++) {
1148            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1149
1150            float u1 = float(x) / meshWidth;
1151            float u2 = float(x + 1) / meshWidth;
1152            float v1 = float(y) / meshHeight;
1153            float v2 = float(y + 1) / meshHeight;
1154
1155            int ax = i + (meshWidth + 1) * 2;
1156            int ay = ax + 1;
1157            int bx = i;
1158            int by = bx + 1;
1159            int cx = i + 2;
1160            int cy = cx + 1;
1161            int dx = i + (meshWidth + 1) * 2 + 2;
1162            int dy = dx + 1;
1163
1164            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1165            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1166            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1167
1168            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1169            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1170            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1171
1172#if RENDER_LAYERS_AS_REGIONS
1173            if (hasActiveLayer) {
1174                // TODO: This could be optimized to avoid unnecessary ops
1175                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1176                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1177                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1178                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1179            }
1180#endif
1181        }
1182    }
1183
1184#if RENDER_LAYERS_AS_REGIONS
1185    if (hasActiveLayer) {
1186        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1187    }
1188#endif
1189
1190    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1191            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1192            GL_TRIANGLES, count, false, false, 0, false, false);
1193}
1194
1195void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1196         float srcLeft, float srcTop, float srcRight, float srcBottom,
1197         float dstLeft, float dstTop, float dstRight, float dstBottom,
1198         SkPaint* paint) {
1199    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1200        return;
1201    }
1202
1203    glActiveTexture(gTextureUnits[0]);
1204    Texture* texture = mCaches.textureCache.get(bitmap);
1205    if (!texture) return;
1206    const AutoTexture autoCleanup(texture);
1207    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1208
1209    const float width = texture->width;
1210    const float height = texture->height;
1211
1212    const float u1 = srcLeft / width;
1213    const float v1 = srcTop / height;
1214    const float u2 = srcRight / width;
1215    const float v2 = srcBottom / height;
1216
1217    mCaches.unbindMeshBuffer();
1218    resetDrawTextureTexCoords(u1, v1, u2, v2);
1219
1220    int alpha;
1221    SkXfermode::Mode mode;
1222    getAlphaAndMode(paint, &alpha, &mode);
1223
1224    if (mSnapshot->transform->isPureTranslate()) {
1225        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1226        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1227
1228        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1229                texture->id, alpha / 255.0f, mode, texture->blend,
1230                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1231                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1232    } else {
1233        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1234                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1235                GL_TRIANGLE_STRIP, gMeshCount);
1236    }
1237
1238    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1239}
1240
1241void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1242        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1243        float left, float top, float right, float bottom, SkPaint* paint) {
1244    if (quickReject(left, top, right, bottom)) {
1245        return;
1246    }
1247
1248    glActiveTexture(gTextureUnits[0]);
1249    Texture* texture = mCaches.textureCache.get(bitmap);
1250    if (!texture) return;
1251    const AutoTexture autoCleanup(texture);
1252    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1253
1254    int alpha;
1255    SkXfermode::Mode mode;
1256    getAlphaAndMode(paint, &alpha, &mode);
1257
1258    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1259            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1260
1261    if (mesh && mesh->verticesCount > 0) {
1262        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1263#if RENDER_LAYERS_AS_REGIONS
1264        // Mark the current layer dirty where we are going to draw the patch
1265        if (hasLayer() && mesh->hasEmptyQuads) {
1266            const float offsetX = left + mSnapshot->transform->getTranslateX();
1267            const float offsetY = top + mSnapshot->transform->getTranslateY();
1268            const size_t count = mesh->quads.size();
1269            for (size_t i = 0; i < count; i++) {
1270                const Rect& bounds = mesh->quads.itemAt(i);
1271                if (pureTranslate) {
1272                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1273                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1274                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1275                } else {
1276                    dirtyLayer(left + bounds.left, top + bounds.top,
1277                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1278                }
1279            }
1280        }
1281#endif
1282
1283        if (pureTranslate) {
1284            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1285            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1286
1287            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1288                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1289                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1290                    true, !mesh->hasEmptyQuads);
1291        } else {
1292            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1293                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1294                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1295                    true, !mesh->hasEmptyQuads);
1296        }
1297    }
1298}
1299
1300void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1301    if (mSnapshot->isIgnored()) return;
1302
1303    const bool isAA = paint->isAntiAlias();
1304    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1305    // A stroke width of 0 has a special meaningin Skia:
1306    // it draws an unscaled 1px wide line
1307    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1308
1309    int alpha;
1310    SkXfermode::Mode mode;
1311    getAlphaAndMode(paint, &alpha, &mode);
1312
1313    int verticesCount = count >> 2;
1314    int generatedVerticesCount = 0;
1315    if (!isHairLine) {
1316        // TODO: AA needs more vertices
1317        verticesCount *= 6;
1318    } else {
1319        // TODO: AA will be different
1320        verticesCount *= 2;
1321    }
1322
1323    TextureVertex lines[verticesCount];
1324    TextureVertex* vertex = &lines[0];
1325
1326    setupDraw();
1327    setupDrawColor(paint->getColor(), alpha);
1328    setupDrawColorFilter();
1329    setupDrawShader();
1330    setupDrawBlending(mode);
1331    setupDrawProgram();
1332    setupDrawModelViewIdentity();
1333    setupDrawColorUniforms();
1334    setupDrawColorFilterUniforms();
1335    setupDrawShaderIdentityUniforms();
1336    setupDrawMesh(vertex);
1337
1338    if (!isHairLine) {
1339        // TODO: Handle the AA case
1340        for (int i = 0; i < count; i += 4) {
1341            // a = start point, b = end point
1342            vec2 a(points[i], points[i + 1]);
1343            vec2 b(points[i + 2], points[i + 3]);
1344
1345            // Bias to snap to the same pixels as Skia
1346            a += 0.375;
1347            b += 0.375;
1348
1349            // Find the normal to the line
1350            vec2 n = (b - a).copyNormalized() * strokeWidth;
1351            float x = n.x;
1352            n.x = -n.y;
1353            n.y = x;
1354
1355            // Four corners of the rectangle defining a thick line
1356            vec2 p1 = a - n;
1357            vec2 p2 = a + n;
1358            vec2 p3 = b + n;
1359            vec2 p4 = b - n;
1360
1361            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1362            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1363            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1364            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1365
1366            if (!quickReject(left, top, right, bottom)) {
1367                // Draw the line as 2 triangles, could be optimized
1368                // by using only 4 vertices and the correct indices
1369                // Also we should probably used non textured vertices
1370                // when line AA is disabled to save on bandwidth
1371                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1372                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1373                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1374                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1375                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1376                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1377
1378                generatedVerticesCount += 6;
1379
1380                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1381            }
1382        }
1383
1384        if (generatedVerticesCount > 0) {
1385            // GL_LINE does not give the result we want to match Skia
1386            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1387        }
1388    } else {
1389        // TODO: Handle the AA case
1390        for (int i = 0; i < count; i += 4) {
1391            const float left = fmin(points[i], points[i + 1]);
1392            const float right = fmax(points[i], points[i + 1]);
1393            const float top = fmin(points[i + 2], points[i + 3]);
1394            const float bottom = fmax(points[i + 2], points[i + 3]);
1395
1396            if (!quickReject(left, top, right, bottom)) {
1397                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1398                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1399
1400                generatedVerticesCount += 2;
1401
1402                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1403            }
1404        }
1405
1406        if (generatedVerticesCount > 0) {
1407            glLineWidth(1.0f);
1408            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1409        }
1410    }
1411}
1412
1413void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1414    // No need to check against the clip, we fill the clip region
1415    if (mSnapshot->isIgnored()) return;
1416
1417    Rect& clip(*mSnapshot->clipRect);
1418    clip.snapToPixelBoundaries();
1419
1420    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1421}
1422
1423void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1424    if (!texture) return;
1425    const AutoTexture autoCleanup(texture);
1426
1427    const float x = left + texture->left - texture->offset;
1428    const float y = top + texture->top - texture->offset;
1429
1430    drawPathTexture(texture, x, y, paint);
1431}
1432
1433void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1434        float rx, float ry, SkPaint* paint) {
1435    if (mSnapshot->isIgnored()) return;
1436
1437    glActiveTexture(gTextureUnits[0]);
1438    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1439            right - left, bottom - top, rx, ry, paint);
1440    drawShape(left, top, texture, paint);
1441}
1442
1443void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1444    if (mSnapshot->isIgnored()) return;
1445
1446    glActiveTexture(gTextureUnits[0]);
1447    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1448    drawShape(x - radius, y - radius, texture, paint);
1449}
1450
1451void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1452    if (mSnapshot->isIgnored()) return;
1453
1454    glActiveTexture(gTextureUnits[0]);
1455    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1456    drawShape(left, top, texture, paint);
1457}
1458
1459void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1460        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1461    if (mSnapshot->isIgnored()) return;
1462
1463    if (fabs(sweepAngle) >= 360.0f) {
1464        drawOval(left, top, right, bottom, paint);
1465        return;
1466    }
1467
1468    glActiveTexture(gTextureUnits[0]);
1469    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1470            startAngle, sweepAngle, useCenter, paint);
1471    drawShape(left, top, texture, paint);
1472}
1473
1474void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1475        SkPaint* paint) {
1476    if (mSnapshot->isIgnored()) return;
1477
1478    glActiveTexture(gTextureUnits[0]);
1479    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1480    drawShape(left, top, texture, paint);
1481}
1482
1483void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1484    if (p->getStyle() != SkPaint::kFill_Style) {
1485        drawRectAsShape(left, top, right, bottom, p);
1486        return;
1487    }
1488
1489    if (quickReject(left, top, right, bottom)) {
1490        return;
1491    }
1492
1493    SkXfermode::Mode mode;
1494    if (!mCaches.extensions.hasFramebufferFetch()) {
1495        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1496        if (!isMode) {
1497            // Assume SRC_OVER
1498            mode = SkXfermode::kSrcOver_Mode;
1499        }
1500    } else {
1501        mode = getXfermode(p->getXfermode());
1502    }
1503
1504    int color = p->getColor();
1505    drawColorRect(left, top, right, bottom, color, mode);
1506}
1507
1508void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1509        float x, float y, SkPaint* paint) {
1510    if (text == NULL || count == 0) {
1511        return;
1512    }
1513    if (mSnapshot->isIgnored()) return;
1514
1515    paint->setAntiAlias(true);
1516
1517    float length = -1.0f;
1518    switch (paint->getTextAlign()) {
1519        case SkPaint::kCenter_Align:
1520            length = paint->measureText(text, bytesCount);
1521            x -= length / 2.0f;
1522            break;
1523        case SkPaint::kRight_Align:
1524            length = paint->measureText(text, bytesCount);
1525            x -= length;
1526            break;
1527        default:
1528            break;
1529    }
1530
1531    const float oldX = x;
1532    const float oldY = y;
1533    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1534    if (pureTranslate) {
1535        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1536        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1537    }
1538
1539    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1540    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1541            paint->getTextSize());
1542
1543    int alpha;
1544    SkXfermode::Mode mode;
1545    getAlphaAndMode(paint, &alpha, &mode);
1546
1547    if (mHasShadow) {
1548        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1549        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1550                count, mShadowRadius);
1551        const AutoTexture autoCleanup(shadow);
1552
1553        const float sx = x - shadow->left + mShadowDx;
1554        const float sy = y - shadow->top + mShadowDy;
1555
1556        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1557
1558        glActiveTexture(gTextureUnits[0]);
1559        setupDraw();
1560        setupDrawWithTexture(true);
1561        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1562        setupDrawBlending(true, mode);
1563        setupDrawProgram();
1564        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1565        setupDrawTexture(shadow->id);
1566        setupDrawPureColorUniforms();
1567        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1568
1569        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1570        finishDrawTexture();
1571    }
1572
1573    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1574        return;
1575    }
1576
1577    // Pick the appropriate texture filtering
1578    bool linearFilter = mSnapshot->transform->changesBounds();
1579    if (pureTranslate && !linearFilter) {
1580        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1581    }
1582
1583    glActiveTexture(gTextureUnits[0]);
1584    setupDraw();
1585    setupDrawDirtyRegionsDisabled();
1586    setupDrawWithTexture(true);
1587    setupDrawAlpha8Color(paint->getColor(), alpha);
1588    setupDrawColorFilter();
1589    setupDrawShader();
1590    setupDrawBlending(true, mode);
1591    setupDrawProgram();
1592    setupDrawModelView(x, y, x, y, pureTranslate, true);
1593    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1594    setupDrawPureColorUniforms();
1595    setupDrawColorFilterUniforms();
1596    setupDrawShaderUniforms(pureTranslate);
1597
1598    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1599    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1600
1601#if RENDER_LAYERS_AS_REGIONS
1602    bool hasActiveLayer = hasLayer();
1603#else
1604    bool hasActiveLayer = false;
1605#endif
1606    mCaches.unbindMeshBuffer();
1607
1608    // Tell font renderer the locations of position and texture coord
1609    // attributes so it can bind its data properly
1610    int positionSlot = mCaches.currentProgram->position;
1611    fontRenderer.setAttributeBindingSlots(positionSlot, mTexCoordsSlot);
1612    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1613            hasActiveLayer ? &bounds : NULL)) {
1614#if RENDER_LAYERS_AS_REGIONS
1615        if (hasActiveLayer) {
1616            if (!pureTranslate) {
1617                mSnapshot->transform->mapRect(bounds);
1618            }
1619            dirtyLayerUnchecked(bounds, getRegion());
1620        }
1621#endif
1622    }
1623
1624    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1625    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1626
1627    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1628}
1629
1630void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1631    if (mSnapshot->isIgnored()) return;
1632
1633    glActiveTexture(gTextureUnits[0]);
1634
1635    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1636    if (!texture) return;
1637    const AutoTexture autoCleanup(texture);
1638
1639    const float x = texture->left - texture->offset;
1640    const float y = texture->top - texture->offset;
1641
1642    drawPathTexture(texture, x, y, paint);
1643}
1644
1645void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1646    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1647        return;
1648    }
1649
1650    glActiveTexture(gTextureUnits[0]);
1651
1652    int alpha;
1653    SkXfermode::Mode mode;
1654    getAlphaAndMode(paint, &alpha, &mode);
1655
1656    layer->alpha = alpha;
1657    layer->mode = mode;
1658
1659#if RENDER_LAYERS_AS_REGIONS
1660    if (!layer->region.isEmpty()) {
1661#if RENDER_LAYERS_RECT_AS_RECT
1662        if (layer->region.isRect()) {
1663            const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1664            composeLayerRect(layer, r);
1665        } else if (layer->mesh) {
1666#else
1667        if (layer->mesh) {
1668#endif
1669            const float a = alpha / 255.0f;
1670            const Rect& rect = layer->layer;
1671
1672            setupDraw();
1673            setupDrawWithTexture();
1674            setupDrawColor(a, a, a, a);
1675            setupDrawColorFilter();
1676            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1677            setupDrawProgram();
1678            setupDrawPureColorUniforms();
1679            setupDrawColorFilterUniforms();
1680            setupDrawTexture(layer->texture);
1681            // TODO: The current layer, if any, will be dirtied with the bounding box
1682            //       of the layer we are drawing. Since the layer we are drawing has
1683            //       a mesh, we know the dirty region, we should use it instead
1684            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1685            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1686
1687            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1688                    GL_UNSIGNED_SHORT, layer->meshIndices);
1689
1690            finishDrawTexture();
1691
1692#if DEBUG_LAYERS_AS_REGIONS
1693            drawRegionRects(layer->region);
1694#endif
1695        }
1696    }
1697#else
1698    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1699    composeLayerRect(layer, r);
1700#endif
1701}
1702
1703///////////////////////////////////////////////////////////////////////////////
1704// Shaders
1705///////////////////////////////////////////////////////////////////////////////
1706
1707void OpenGLRenderer::resetShader() {
1708    mShader = NULL;
1709}
1710
1711void OpenGLRenderer::setupShader(SkiaShader* shader) {
1712    mShader = shader;
1713    if (mShader) {
1714        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1715    }
1716}
1717
1718///////////////////////////////////////////////////////////////////////////////
1719// Color filters
1720///////////////////////////////////////////////////////////////////////////////
1721
1722void OpenGLRenderer::resetColorFilter() {
1723    mColorFilter = NULL;
1724}
1725
1726void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1727    mColorFilter = filter;
1728}
1729
1730///////////////////////////////////////////////////////////////////////////////
1731// Drop shadow
1732///////////////////////////////////////////////////////////////////////////////
1733
1734void OpenGLRenderer::resetShadow() {
1735    mHasShadow = false;
1736}
1737
1738void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1739    mHasShadow = true;
1740    mShadowRadius = radius;
1741    mShadowDx = dx;
1742    mShadowDy = dy;
1743    mShadowColor = color;
1744}
1745
1746///////////////////////////////////////////////////////////////////////////////
1747// Drawing implementation
1748///////////////////////////////////////////////////////////////////////////////
1749
1750void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1751        float x, float y, SkPaint* paint) {
1752    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1753        return;
1754    }
1755
1756    int alpha;
1757    SkXfermode::Mode mode;
1758    getAlphaAndMode(paint, &alpha, &mode);
1759
1760    setupDraw();
1761    setupDrawWithTexture(true);
1762    setupDrawAlpha8Color(paint->getColor(), alpha);
1763    setupDrawColorFilter();
1764    setupDrawShader();
1765    setupDrawBlending(true, mode);
1766    setupDrawProgram();
1767    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1768    setupDrawTexture(texture->id);
1769    setupDrawPureColorUniforms();
1770    setupDrawColorFilterUniforms();
1771    setupDrawShaderUniforms();
1772    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1773
1774    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1775
1776    finishDrawTexture();
1777}
1778
1779// Same values used by Skia
1780#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1781#define kStdUnderline_Offset    (1.0f / 9.0f)
1782#define kStdUnderline_Thickness (1.0f / 18.0f)
1783
1784void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1785        float x, float y, SkPaint* paint) {
1786    // Handle underline and strike-through
1787    uint32_t flags = paint->getFlags();
1788    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1789        float underlineWidth = length;
1790        // If length is > 0.0f, we already measured the text for the text alignment
1791        if (length <= 0.0f) {
1792            underlineWidth = paint->measureText(text, bytesCount);
1793        }
1794
1795        float offsetX = 0;
1796        switch (paint->getTextAlign()) {
1797            case SkPaint::kCenter_Align:
1798                offsetX = underlineWidth * 0.5f;
1799                break;
1800            case SkPaint::kRight_Align:
1801                offsetX = underlineWidth;
1802                break;
1803            default:
1804                break;
1805        }
1806
1807        if (underlineWidth > 0.0f) {
1808            const float textSize = paint->getTextSize();
1809            // TODO: Support stroke width < 1.0f when we have AA lines
1810            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
1811
1812            const float left = x - offsetX;
1813            float top = 0.0f;
1814
1815            int linesCount = 0;
1816            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
1817            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
1818
1819            const int pointsCount = 4 * linesCount;
1820            float points[pointsCount];
1821            int currentPoint = 0;
1822
1823            if (flags & SkPaint::kUnderlineText_Flag) {
1824                top = y + textSize * kStdUnderline_Offset;
1825                points[currentPoint++] = left;
1826                points[currentPoint++] = top;
1827                points[currentPoint++] = left + underlineWidth;
1828                points[currentPoint++] = top;
1829            }
1830
1831            if (flags & SkPaint::kStrikeThruText_Flag) {
1832                top = y + textSize * kStdStrikeThru_Offset;
1833                points[currentPoint++] = left;
1834                points[currentPoint++] = top;
1835                points[currentPoint++] = left + underlineWidth;
1836                points[currentPoint++] = top;
1837            }
1838
1839            SkPaint linesPaint(*paint);
1840            linesPaint.setStrokeWidth(strokeWidth);
1841
1842            drawLines(&points[0], pointsCount, &linesPaint);
1843        }
1844    }
1845}
1846
1847void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1848        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1849    // If a shader is set, preserve only the alpha
1850    if (mShader) {
1851        color |= 0x00ffffff;
1852    }
1853
1854    setupDraw();
1855    setupDrawColor(color);
1856    setupDrawShader();
1857    setupDrawColorFilter();
1858    setupDrawBlending(mode);
1859    setupDrawProgram();
1860    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1861    setupDrawColorUniforms();
1862    setupDrawShaderUniforms(ignoreTransform);
1863    setupDrawColorFilterUniforms();
1864    setupDrawSimpleMesh();
1865
1866    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1867}
1868
1869void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1870        Texture* texture, SkPaint* paint) {
1871    int alpha;
1872    SkXfermode::Mode mode;
1873    getAlphaAndMode(paint, &alpha, &mode);
1874
1875    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1876
1877    if (mSnapshot->transform->isPureTranslate()) {
1878        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1879        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1880
1881        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1882                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1883                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1884    } else {
1885        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1886                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1887                GL_TRIANGLE_STRIP, gMeshCount);
1888    }
1889}
1890
1891void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1892        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1893    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1894            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1895}
1896
1897void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1898        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1899        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1900        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1901
1902    setupDraw();
1903    setupDrawWithTexture();
1904    setupDrawColor(alpha, alpha, alpha, alpha);
1905    setupDrawColorFilter();
1906    setupDrawBlending(blend, mode, swapSrcDst);
1907    setupDrawProgram();
1908    if (!dirty) {
1909        setupDrawDirtyRegionsDisabled();
1910    }
1911    if (!ignoreScale) {
1912        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1913    } else {
1914        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1915    }
1916    setupDrawPureColorUniforms();
1917    setupDrawColorFilterUniforms();
1918    setupDrawTexture(texture);
1919    setupDrawMesh(vertices, texCoords, vbo);
1920
1921    glDrawArrays(drawMode, 0, elementsCount);
1922
1923    finishDrawTexture();
1924}
1925
1926void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1927        ProgramDescription& description, bool swapSrcDst) {
1928    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1929    if (blend) {
1930        if (mode < SkXfermode::kPlus_Mode) {
1931            if (!mCaches.blend) {
1932                glEnable(GL_BLEND);
1933            }
1934
1935            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1936            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1937
1938            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1939                glBlendFunc(sourceMode, destMode);
1940                mCaches.lastSrcMode = sourceMode;
1941                mCaches.lastDstMode = destMode;
1942            }
1943        } else {
1944            // These blend modes are not supported by OpenGL directly and have
1945            // to be implemented using shaders. Since the shader will perform
1946            // the blending, turn blending off here
1947            if (mCaches.extensions.hasFramebufferFetch()) {
1948                description.framebufferMode = mode;
1949                description.swapSrcDst = swapSrcDst;
1950            }
1951
1952            if (mCaches.blend) {
1953                glDisable(GL_BLEND);
1954            }
1955            blend = false;
1956        }
1957    } else if (mCaches.blend) {
1958        glDisable(GL_BLEND);
1959    }
1960    mCaches.blend = blend;
1961}
1962
1963bool OpenGLRenderer::useProgram(Program* program) {
1964    if (!program->isInUse()) {
1965        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1966        program->use();
1967        mCaches.currentProgram = program;
1968        return false;
1969    }
1970    return true;
1971}
1972
1973void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1974    TextureVertex* v = &mMeshVertices[0];
1975    TextureVertex::setUV(v++, u1, v1);
1976    TextureVertex::setUV(v++, u2, v1);
1977    TextureVertex::setUV(v++, u1, v2);
1978    TextureVertex::setUV(v++, u2, v2);
1979}
1980
1981void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1982    if (paint) {
1983        if (!mCaches.extensions.hasFramebufferFetch()) {
1984            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1985            if (!isMode) {
1986                // Assume SRC_OVER
1987                *mode = SkXfermode::kSrcOver_Mode;
1988            }
1989        } else {
1990            *mode = getXfermode(paint->getXfermode());
1991        }
1992
1993        // Skia draws using the color's alpha channel if < 255
1994        // Otherwise, it uses the paint's alpha
1995        int color = paint->getColor();
1996        *alpha = (color >> 24) & 0xFF;
1997        if (*alpha == 255) {
1998            *alpha = paint->getAlpha();
1999        }
2000    } else {
2001        *mode = SkXfermode::kSrcOver_Mode;
2002        *alpha = 255;
2003    }
2004}
2005
2006SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
2007    // In the future we should look at unifying the Porter-Duff modes and
2008    // SkXferModes so that we can use SkXfermode::IsMode(xfer, &mode).
2009    if (mode == NULL) {
2010        return SkXfermode::kSrcOver_Mode;
2011    }
2012    return mode->fMode;
2013}
2014
2015void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
2016    bool bound = false;
2017    if (wrapS != texture->wrapS) {
2018        glBindTexture(GL_TEXTURE_2D, texture->id);
2019        bound = true;
2020        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
2021        texture->wrapS = wrapS;
2022    }
2023    if (wrapT != texture->wrapT) {
2024        if (!bound) {
2025            glBindTexture(GL_TEXTURE_2D, texture->id);
2026        }
2027        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
2028        texture->wrapT = wrapT;
2029    }
2030}
2031
2032}; // namespace uirenderer
2033}; // namespace android
2034