OpenGLRenderer.cpp revision ed8f8dd8cf621d6046db7e083f8a36205ed55609 
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    mCaches.clearGarbage();
140
141    mSnapshot = new Snapshot(mFirstSnapshot,
142            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
143    mSaveCount = 1;
144
145    glViewport(0, 0, mWidth, mHeight);
146
147    glDisable(GL_DITHER);
148
149    if (!opaque) {
150        glDisable(GL_SCISSOR_TEST);
151        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
152        glClear(GL_COLOR_BUFFER_BIT);
153    }
154
155    glEnable(GL_SCISSOR_TEST);
156    glScissor(0, 0, mWidth, mHeight);
157    mSnapshot->setClip(0.0f, 0.0f, mWidth, mHeight);
158}
159
160void OpenGLRenderer::finish() {
161#if DEBUG_OPENGL
162    GLenum status = GL_NO_ERROR;
163    while ((status = glGetError()) != GL_NO_ERROR) {
164        LOGD("GL error from OpenGLRenderer: 0x%x", status);
165        switch (status) {
166            case GL_OUT_OF_MEMORY:
167                LOGE("  OpenGLRenderer is out of memory!");
168                break;
169        }
170    }
171#endif
172#if DEBUG_MEMORY_USAGE
173    mCaches.dumpMemoryUsage();
174#else
175    if (mCaches.getDebugLevel() & kDebugMemory) {
176        mCaches.dumpMemoryUsage();
177    }
178#endif
179}
180
181void OpenGLRenderer::interrupt() {
182    if (mCaches.currentProgram) {
183        if (mCaches.currentProgram->isInUse()) {
184            mCaches.currentProgram->remove();
185            mCaches.currentProgram = NULL;
186        }
187    }
188    mCaches.unbindMeshBuffer();
189}
190
191void OpenGLRenderer::acquireContext() {
192    interrupt();
193}
194
195void OpenGLRenderer::resume() {
196    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
197
198    glEnable(GL_SCISSOR_TEST);
199    dirtyClip();
200
201    glDisable(GL_DITHER);
202
203    glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
204    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
205
206    mCaches.blend = true;
207    glEnable(GL_BLEND);
208    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
209    glBlendEquation(GL_FUNC_ADD);
210}
211
212void OpenGLRenderer::releaseContext() {
213    resume();
214}
215
216///////////////////////////////////////////////////////////////////////////////
217// State management
218///////////////////////////////////////////////////////////////////////////////
219
220int OpenGLRenderer::getSaveCount() const {
221    return mSaveCount;
222}
223
224int OpenGLRenderer::save(int flags) {
225    return saveSnapshot(flags);
226}
227
228void OpenGLRenderer::restore() {
229    if (mSaveCount > 1) {
230        restoreSnapshot();
231    }
232}
233
234void OpenGLRenderer::restoreToCount(int saveCount) {
235    if (saveCount < 1) saveCount = 1;
236
237    while (mSaveCount > saveCount) {
238        restoreSnapshot();
239    }
240}
241
242int OpenGLRenderer::saveSnapshot(int flags) {
243    mSnapshot = new Snapshot(mSnapshot, flags);
244    return mSaveCount++;
245}
246
247bool OpenGLRenderer::restoreSnapshot() {
248    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
249    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
250    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
251
252    sp<Snapshot> current = mSnapshot;
253    sp<Snapshot> previous = mSnapshot->previous;
254
255    if (restoreOrtho) {
256        Rect& r = previous->viewport;
257        glViewport(r.left, r.top, r.right, r.bottom);
258        mOrthoMatrix.load(current->orthoMatrix);
259    }
260
261    mSaveCount--;
262    mSnapshot = previous;
263
264    if (restoreClip) {
265        dirtyClip();
266    }
267
268    if (restoreLayer) {
269        composeLayer(current, previous);
270    }
271
272    return restoreClip;
273}
274
275///////////////////////////////////////////////////////////////////////////////
276// Layers
277///////////////////////////////////////////////////////////////////////////////
278
279int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
280        SkPaint* p, int flags) {
281    const GLuint previousFbo = mSnapshot->fbo;
282    const int count = saveSnapshot(flags);
283
284    if (!mSnapshot->isIgnored()) {
285        int alpha = 255;
286        SkXfermode::Mode mode;
287
288        if (p) {
289            alpha = p->getAlpha();
290            if (!mCaches.extensions.hasFramebufferFetch()) {
291                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
292                if (!isMode) {
293                    // Assume SRC_OVER
294                    mode = SkXfermode::kSrcOver_Mode;
295                }
296            } else {
297                mode = getXfermode(p->getXfermode());
298            }
299        } else {
300            mode = SkXfermode::kSrcOver_Mode;
301        }
302
303        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
304    }
305
306    return count;
307}
308
309int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
310        int alpha, int flags) {
311    if (alpha >= 255 - ALPHA_THRESHOLD) {
312        return saveLayer(left, top, right, bottom, NULL, flags);
313    } else {
314        SkPaint paint;
315        paint.setAlpha(alpha);
316        return saveLayer(left, top, right, bottom, &paint, flags);
317    }
318}
319
320/**
321 * Layers are viewed by Skia are slightly different than layers in image editing
322 * programs (for instance.) When a layer is created, previously created layers
323 * and the frame buffer still receive every drawing command. For instance, if a
324 * layer is created and a shape intersecting the bounds of the layers and the
325 * framebuffer is draw, the shape will be drawn on both (unless the layer was
326 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
327 *
328 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
329 * texture. Unfortunately, this is inefficient as it requires every primitive to
330 * be drawn n + 1 times, where n is the number of active layers. In practice this
331 * means, for every primitive:
332 *   - Switch active frame buffer
333 *   - Change viewport, clip and projection matrix
334 *   - Issue the drawing
335 *
336 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
337 * To avoid this, layers are implemented in a different way here, at least in the
338 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
339 * is set. When this flag is set we can redirect all drawing operations into a
340 * single FBO.
341 *
342 * This implementation relies on the frame buffer being at least RGBA 8888. When
343 * a layer is created, only a texture is created, not an FBO. The content of the
344 * frame buffer contained within the layer's bounds is copied into this texture
345 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
346 * buffer and drawing continues as normal. This technique therefore treats the
347 * frame buffer as a scratch buffer for the layers.
348 *
349 * To compose the layers back onto the frame buffer, each layer texture
350 * (containing the original frame buffer data) is drawn as a simple quad over
351 * the frame buffer. The trick is that the quad is set as the composition
352 * destination in the blending equation, and the frame buffer becomes the source
353 * of the composition.
354 *
355 * Drawing layers with an alpha value requires an extra step before composition.
356 * An empty quad is drawn over the layer's region in the frame buffer. This quad
357 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
358 * quad is used to multiply the colors in the frame buffer. This is achieved by
359 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
360 * GL_ZERO, GL_SRC_ALPHA.
361 *
362 * Because glCopyTexImage2D() can be slow, an alternative implementation might
363 * be use to draw a single clipped layer. The implementation described above
364 * is correct in every case.
365 *
366 * (1) The frame buffer is actually not cleared right away. To allow the GPU
367 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
368 *     buffer is left untouched until the first drawing operation. Only when
369 *     something actually gets drawn are the layers regions cleared.
370 */
371bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
372        float right, float bottom, int alpha, SkXfermode::Mode mode,
373        int flags, GLuint previousFbo) {
374    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
375    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
376
377    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
378
379    // Window coordinates of the layer
380    Rect bounds(left, top, right, bottom);
381    if (fboLayer) {
382        // Clear the previous layer regions before we change the viewport
383        clearLayerRegions();
384    } else {
385        mSnapshot->transform->mapRect(bounds);
386
387        // Layers only make sense if they are in the framebuffer's bounds
388        bounds.intersect(*snapshot->clipRect);
389
390        // We cannot work with sub-pixels in this case
391        bounds.snapToPixelBoundaries();
392
393        // When the layer is not an FBO, we may use glCopyTexImage so we
394        // need to make sure the layer does not extend outside the bounds
395        // of the framebuffer
396        bounds.intersect(snapshot->previous->viewport);
397    }
398
399    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
400            bounds.getHeight() > mCaches.maxTextureSize) {
401        snapshot->empty = fboLayer;
402    } else {
403        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
404    }
405
406    // Bail out if we won't draw in this snapshot
407    if (snapshot->invisible || snapshot->empty) {
408        return false;
409    }
410
411    glActiveTexture(gTextureUnits[0]);
412    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
413    if (!layer) {
414        return false;
415    }
416
417    layer->mode = mode;
418    layer->alpha = alpha;
419    layer->layer.set(bounds);
420    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
421            bounds.getWidth() / float(layer->width), 0.0f);
422    layer->colorFilter = mColorFilter;
423
424    // Save the layer in the snapshot
425    snapshot->flags |= Snapshot::kFlagIsLayer;
426    snapshot->layer = layer;
427
428    if (fboLayer) {
429        return createFboLayer(layer, bounds, snapshot, previousFbo);
430    } else {
431        // Copy the framebuffer into the layer
432        glBindTexture(GL_TEXTURE_2D, layer->texture);
433        if (!bounds.isEmpty()) {
434            if (layer->empty) {
435                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
436                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
437                layer->empty = false;
438            } else {
439                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
440                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
441            }
442            // Enqueue the buffer coordinates to clear the corresponding region later
443            mLayers.push(new Rect(bounds));
444        }
445    }
446
447    return true;
448}
449
450bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
451        GLuint previousFbo) {
452    layer->fbo = mCaches.fboCache.get();
453
454#if RENDER_LAYERS_AS_REGIONS
455    snapshot->region = &snapshot->layer->region;
456    snapshot->flags |= Snapshot::kFlagFboTarget;
457#endif
458
459    Rect clip(bounds);
460    snapshot->transform->mapRect(clip);
461    clip.intersect(*snapshot->clipRect);
462    clip.snapToPixelBoundaries();
463    clip.intersect(snapshot->previous->viewport);
464
465    mat4 inverse;
466    inverse.loadInverse(*mSnapshot->transform);
467
468    inverse.mapRect(clip);
469    clip.snapToPixelBoundaries();
470    clip.intersect(bounds);
471    clip.translate(-bounds.left, -bounds.top);
472
473    snapshot->flags |= Snapshot::kFlagIsFboLayer;
474    snapshot->fbo = layer->fbo;
475    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
476    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
477    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
478    snapshot->height = bounds.getHeight();
479    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
480    snapshot->orthoMatrix.load(mOrthoMatrix);
481
482    // Bind texture to FBO
483    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
484    glBindTexture(GL_TEXTURE_2D, layer->texture);
485
486    // Initialize the texture if needed
487    if (layer->empty) {
488        layer->empty = false;
489        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
490                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
491    }
492
493    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
494            layer->texture, 0);
495
496#if DEBUG_LAYERS_AS_REGIONS
497    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
498    if (status != GL_FRAMEBUFFER_COMPLETE) {
499        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
500
501        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
502        glDeleteTextures(1, &layer->texture);
503        mCaches.fboCache.put(layer->fbo);
504
505        delete layer;
506
507        return false;
508    }
509#endif
510
511    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
512    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
513            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
514    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
515    glClear(GL_COLOR_BUFFER_BIT);
516
517    dirtyClip();
518
519    // Change the ortho projection
520    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
521    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
522
523    return true;
524}
525
526/**
527 * Read the documentation of createLayer() before doing anything in this method.
528 */
529void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
530    if (!current->layer) {
531        LOGE("Attempting to compose a layer that does not exist");
532        return;
533    }
534
535    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
536
537    if (fboLayer) {
538        // Unbind current FBO and restore previous one
539        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
540    }
541
542    Layer* layer = current->layer;
543    const Rect& rect = layer->layer;
544
545    if (!fboLayer && layer->alpha < 255) {
546        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
547                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
548        // Required below, composeLayerRect() will divide by 255
549        layer->alpha = 255;
550    }
551
552    mCaches.unbindMeshBuffer();
553
554    glActiveTexture(gTextureUnits[0]);
555
556    // When the layer is stored in an FBO, we can save a bit of fillrate by
557    // drawing only the dirty region
558    if (fboLayer) {
559        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
560        if (layer->colorFilter) {
561            setupColorFilter(layer->colorFilter);
562        }
563        composeLayerRegion(layer, rect);
564        if (layer->colorFilter) {
565            resetColorFilter();
566        }
567    } else {
568        if (!rect.isEmpty()) {
569            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
570            composeLayerRect(layer, rect, true);
571        }
572    }
573
574    if (fboLayer) {
575        // Detach the texture from the FBO
576        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
577        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
578        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
579
580        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
581        mCaches.fboCache.put(current->fbo);
582    }
583
584    dirtyClip();
585
586    // Failing to add the layer to the cache should happen only if the layer is too large
587    if (!mCaches.layerCache.put(layer)) {
588        LAYER_LOGD("Deleting layer");
589        glDeleteTextures(1, &layer->texture);
590        delete layer;
591    }
592}
593
594void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
595    const Rect& texCoords = layer->texCoords;
596    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
597
598    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
599            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
600            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
601
602    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
603}
604
605void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
606#if RENDER_LAYERS_AS_REGIONS
607    if (layer->region.isRect()) {
608        composeLayerRect(layer, rect);
609        layer->region.clear();
610        return;
611    }
612
613    if (!layer->region.isEmpty()) {
614        size_t count;
615        const android::Rect* rects = layer->region.getArray(&count);
616
617        const float alpha = layer->alpha / 255.0f;
618        const float texX = 1.0f / float(layer->width);
619        const float texY = 1.0f / float(layer->height);
620        const float height = rect.getHeight();
621
622        TextureVertex* mesh = mCaches.getRegionMesh();
623        GLsizei numQuads = 0;
624
625        setupDraw();
626        setupDrawWithTexture();
627        setupDrawColor(alpha, alpha, alpha, alpha);
628        setupDrawColorFilter();
629        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
630        setupDrawProgram();
631        setupDrawDirtyRegionsDisabled();
632        setupDrawPureColorUniforms();
633        setupDrawColorFilterUniforms();
634        setupDrawTexture(layer->texture);
635        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
636        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
637
638        for (size_t i = 0; i < count; i++) {
639            const android::Rect* r = &rects[i];
640
641            const float u1 = r->left * texX;
642            const float v1 = (height - r->top) * texY;
643            const float u2 = r->right * texX;
644            const float v2 = (height - r->bottom) * texY;
645
646            // TODO: Reject quads outside of the clip
647            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
648            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
649            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
650            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
651
652            numQuads++;
653
654            if (numQuads >= REGION_MESH_QUAD_COUNT) {
655                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
656                numQuads = 0;
657                mesh = mCaches.getRegionMesh();
658            }
659        }
660
661        if (numQuads > 0) {
662            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
663        }
664
665        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
666        finishDrawTexture();
667
668#if DEBUG_LAYERS_AS_REGIONS
669        uint32_t colors[] = {
670                0x7fff0000, 0x7f00ff00,
671                0x7f0000ff, 0x7fff00ff,
672        };
673
674        int offset = 0;
675        int32_t top = rects[0].top;
676        int i = 0;
677
678        for (size_t i = 0; i < count; i++) {
679            if (top != rects[i].top) {
680                offset ^= 0x2;
681                top = rects[i].top;
682            }
683
684            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
685            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
686                    SkXfermode::kSrcOver_Mode);
687        }
688#endif
689
690        layer->region.clear();
691    }
692#else
693    composeLayerRect(layer, rect);
694#endif
695}
696
697void OpenGLRenderer::dirtyLayer(const float left, const float top,
698        const float right, const float bottom, const mat4 transform) {
699#if RENDER_LAYERS_AS_REGIONS
700    if (hasLayer()) {
701        Rect bounds(left, top, right, bottom);
702        transform.mapRect(bounds);
703        dirtyLayerUnchecked(bounds, getRegion());
704    }
705#endif
706}
707
708void OpenGLRenderer::dirtyLayer(const float left, const float top,
709        const float right, const float bottom) {
710#if RENDER_LAYERS_AS_REGIONS
711    if (hasLayer()) {
712        Rect bounds(left, top, right, bottom);
713        dirtyLayerUnchecked(bounds, getRegion());
714    }
715#endif
716}
717
718void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
719#if RENDER_LAYERS_AS_REGIONS
720    if (bounds.intersect(*mSnapshot->clipRect)) {
721        bounds.snapToPixelBoundaries();
722        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
723        if (!dirty.isEmpty()) {
724            region->orSelf(dirty);
725        }
726    }
727#endif
728}
729
730void OpenGLRenderer::clearLayerRegions() {
731    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
732
733    Rect clipRect(*mSnapshot->clipRect);
734    clipRect.snapToPixelBoundaries();
735
736    for (uint32_t i = 0; i < mLayers.size(); i++) {
737        Rect* bounds = mLayers.itemAt(i);
738        if (clipRect.intersects(*bounds)) {
739            // Clear the framebuffer where the layer will draw
740            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
741                    bounds->getWidth(), bounds->getHeight());
742            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
743            glClear(GL_COLOR_BUFFER_BIT);
744
745            // Restore the clip
746            dirtyClip();
747        }
748
749        delete bounds;
750    }
751
752    mLayers.clear();
753}
754
755///////////////////////////////////////////////////////////////////////////////
756// Transforms
757///////////////////////////////////////////////////////////////////////////////
758
759void OpenGLRenderer::translate(float dx, float dy) {
760    mSnapshot->transform->translate(dx, dy, 0.0f);
761}
762
763void OpenGLRenderer::rotate(float degrees) {
764    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
765}
766
767void OpenGLRenderer::scale(float sx, float sy) {
768    mSnapshot->transform->scale(sx, sy, 1.0f);
769}
770
771void OpenGLRenderer::skew(float sx, float sy) {
772    mSnapshot->transform->skew(sx, sy);
773}
774
775void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
776    mSnapshot->transform->load(*matrix);
777}
778
779const float* OpenGLRenderer::getMatrix() const {
780    if (mSnapshot->fbo != 0) {
781        return &mSnapshot->transform->data[0];
782    }
783    return &mIdentity.data[0];
784}
785
786void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
787    mSnapshot->transform->copyTo(*matrix);
788}
789
790void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
791    SkMatrix transform;
792    mSnapshot->transform->copyTo(transform);
793    transform.preConcat(*matrix);
794    mSnapshot->transform->load(transform);
795}
796
797///////////////////////////////////////////////////////////////////////////////
798// Clipping
799///////////////////////////////////////////////////////////////////////////////
800
801void OpenGLRenderer::setScissorFromClip() {
802    Rect clip(*mSnapshot->clipRect);
803    clip.snapToPixelBoundaries();
804    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
805    mDirtyClip = false;
806}
807
808const Rect& OpenGLRenderer::getClipBounds() {
809    return mSnapshot->getLocalClip();
810}
811
812bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
813    if (mSnapshot->isIgnored()) {
814        return true;
815    }
816
817    Rect r(left, top, right, bottom);
818    mSnapshot->transform->mapRect(r);
819    r.snapToPixelBoundaries();
820
821    Rect clipRect(*mSnapshot->clipRect);
822    clipRect.snapToPixelBoundaries();
823
824    return !clipRect.intersects(r);
825}
826
827bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
828    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
829    if (clipped) {
830        dirtyClip();
831    }
832    return !mSnapshot->clipRect->isEmpty();
833}
834
835///////////////////////////////////////////////////////////////////////////////
836// Drawing commands
837///////////////////////////////////////////////////////////////////////////////
838
839void OpenGLRenderer::setupDraw() {
840    clearLayerRegions();
841    if (mDirtyClip) {
842        setScissorFromClip();
843    }
844    mDescription.reset();
845    mSetShaderColor = false;
846    mColorSet = false;
847    mColorA = mColorR = mColorG = mColorB = 0.0f;
848    mTextureUnit = 0;
849    mTrackDirtyRegions = true;
850    mTexCoordsSlot = -1;
851}
852
853void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
854    mDescription.hasTexture = true;
855    mDescription.hasAlpha8Texture = isAlpha8;
856}
857
858void OpenGLRenderer::setupDrawColor(int color) {
859    setupDrawColor(color, (color >> 24) & 0xFF);
860}
861
862void OpenGLRenderer::setupDrawColor(int color, int alpha) {
863    mColorA = alpha / 255.0f;
864    const float a = mColorA / 255.0f;
865    mColorR = a * ((color >> 16) & 0xFF);
866    mColorG = a * ((color >>  8) & 0xFF);
867    mColorB = a * ((color      ) & 0xFF);
868    mColorSet = true;
869    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
870}
871
872void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
873    mColorA = alpha / 255.0f;
874    const float a = mColorA / 255.0f;
875    mColorR = a * ((color >> 16) & 0xFF);
876    mColorG = a * ((color >>  8) & 0xFF);
877    mColorB = a * ((color      ) & 0xFF);
878    mColorSet = true;
879    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
880}
881
882void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
883    mColorA = a;
884    mColorR = r;
885    mColorG = g;
886    mColorB = b;
887    mColorSet = true;
888    mSetShaderColor = mDescription.setColor(r, g, b, a);
889}
890
891void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
892    mColorA = a;
893    mColorR = r;
894    mColorG = g;
895    mColorB = b;
896    mColorSet = true;
897    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
898}
899
900void OpenGLRenderer::setupDrawShader() {
901    if (mShader) {
902        mShader->describe(mDescription, mCaches.extensions);
903    }
904}
905
906void OpenGLRenderer::setupDrawColorFilter() {
907    if (mColorFilter) {
908        mColorFilter->describe(mDescription, mCaches.extensions);
909    }
910}
911
912void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
913    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
914            mDescription, swapSrcDst);
915}
916
917void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
918    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
919            mDescription, swapSrcDst);
920}
921
922void OpenGLRenderer::setupDrawProgram() {
923    useProgram(mCaches.programCache.get(mDescription));
924}
925
926void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
927    mTrackDirtyRegions = false;
928}
929
930void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
931        bool ignoreTransform) {
932    mModelView.loadTranslate(left, top, 0.0f);
933    if (!ignoreTransform) {
934        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
935        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
936    } else {
937        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
938        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
939    }
940}
941
942void OpenGLRenderer::setupDrawModelViewIdentity() {
943    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
944}
945
946void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
947        bool ignoreTransform, bool ignoreModelView) {
948    if (!ignoreModelView) {
949        mModelView.loadTranslate(left, top, 0.0f);
950        mModelView.scale(right - left, bottom - top, 1.0f);
951    } else {
952        mModelView.loadIdentity();
953    }
954    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
955    if (!ignoreTransform) {
956        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
957        if (mTrackDirtyRegions && dirty) {
958            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
959        }
960    } else {
961        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
962        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
963    }
964}
965
966void OpenGLRenderer::setupDrawColorUniforms() {
967    if (mColorSet || (mShader && mSetShaderColor)) {
968        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
969    }
970}
971
972void OpenGLRenderer::setupDrawPureColorUniforms() {
973    if (mSetShaderColor) {
974        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
975    }
976}
977
978void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
979    if (mShader) {
980        if (ignoreTransform) {
981            mModelView.loadInverse(*mSnapshot->transform);
982        }
983        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
984    }
985}
986
987void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
988    if (mShader) {
989        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
990    }
991}
992
993void OpenGLRenderer::setupDrawColorFilterUniforms() {
994    if (mColorFilter) {
995        mColorFilter->setupProgram(mCaches.currentProgram);
996    }
997}
998
999void OpenGLRenderer::setupDrawSimpleMesh() {
1000    mCaches.bindMeshBuffer();
1001    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1002            gMeshStride, 0);
1003}
1004
1005void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1006    bindTexture(texture);
1007    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1008
1009    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1010    glEnableVertexAttribArray(mTexCoordsSlot);
1011}
1012
1013void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1014    if (!vertices) {
1015        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1016    } else {
1017        mCaches.unbindMeshBuffer();
1018    }
1019    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1020            gMeshStride, vertices);
1021    if (mTexCoordsSlot > 0) {
1022        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1023    }
1024}
1025
1026void OpenGLRenderer::finishDrawTexture() {
1027    glDisableVertexAttribArray(mTexCoordsSlot);
1028}
1029
1030///////////////////////////////////////////////////////////////////////////////
1031// Drawing
1032///////////////////////////////////////////////////////////////////////////////
1033
1034void OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t level) {
1035    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1036    // will be performed by the display list itself
1037    if (displayList) {
1038        displayList->replay(*this, level);
1039    }
1040}
1041
1042void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1043    const float right = left + bitmap->width();
1044    const float bottom = top + bitmap->height();
1045
1046    if (quickReject(left, top, right, bottom)) {
1047        return;
1048    }
1049
1050    glActiveTexture(gTextureUnits[0]);
1051    Texture* texture = mCaches.textureCache.get(bitmap);
1052    if (!texture) return;
1053    const AutoTexture autoCleanup(texture);
1054
1055    drawTextureRect(left, top, right, bottom, texture, paint);
1056}
1057
1058void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1059    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1060    const mat4 transform(*matrix);
1061    transform.mapRect(r);
1062
1063    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1064        return;
1065    }
1066
1067    glActiveTexture(gTextureUnits[0]);
1068    Texture* texture = mCaches.textureCache.get(bitmap);
1069    if (!texture) return;
1070    const AutoTexture autoCleanup(texture);
1071
1072    // This could be done in a cheaper way, all we need is pass the matrix
1073    // to the vertex shader. The save/restore is a bit overkill.
1074    save(SkCanvas::kMatrix_SaveFlag);
1075    concatMatrix(matrix);
1076    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1077    restore();
1078}
1079
1080void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1081         float srcLeft, float srcTop, float srcRight, float srcBottom,
1082         float dstLeft, float dstTop, float dstRight, float dstBottom,
1083         SkPaint* paint) {
1084    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1085        return;
1086    }
1087
1088    glActiveTexture(gTextureUnits[0]);
1089    Texture* texture = mCaches.textureCache.get(bitmap);
1090    if (!texture) return;
1091    const AutoTexture autoCleanup(texture);
1092    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1093
1094    const float width = texture->width;
1095    const float height = texture->height;
1096
1097    const float u1 = srcLeft / width;
1098    const float v1 = srcTop / height;
1099    const float u2 = srcRight / width;
1100    const float v2 = srcBottom / height;
1101
1102    mCaches.unbindMeshBuffer();
1103    resetDrawTextureTexCoords(u1, v1, u2, v2);
1104
1105    int alpha;
1106    SkXfermode::Mode mode;
1107    getAlphaAndMode(paint, &alpha, &mode);
1108
1109    if (mSnapshot->transform->isPureTranslate()) {
1110        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1111        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1112
1113        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1114                texture->id, alpha / 255.0f, mode, texture->blend,
1115                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1116                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1117    } else {
1118        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1119                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1120                GL_TRIANGLE_STRIP, gMeshCount);
1121    }
1122
1123    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1124}
1125
1126void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1127        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1128        float left, float top, float right, float bottom, SkPaint* paint) {
1129    if (quickReject(left, top, right, bottom)) {
1130        return;
1131    }
1132
1133    glActiveTexture(gTextureUnits[0]);
1134    Texture* texture = mCaches.textureCache.get(bitmap);
1135    if (!texture) return;
1136    const AutoTexture autoCleanup(texture);
1137    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1138
1139    int alpha;
1140    SkXfermode::Mode mode;
1141    getAlphaAndMode(paint, &alpha, &mode);
1142
1143    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1144            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1145
1146    if (mesh && mesh->verticesCount > 0) {
1147        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1148#if RENDER_LAYERS_AS_REGIONS
1149        // Mark the current layer dirty where we are going to draw the patch
1150        if ((mSnapshot->flags & Snapshot::kFlagFboTarget) &&
1151                mSnapshot->region && mesh->hasEmptyQuads) {
1152            const size_t count = mesh->quads.size();
1153            for (size_t i = 0; i < count; i++) {
1154                const Rect& bounds = mesh->quads.itemAt(i);
1155                if (pureTranslate) {
1156                    const float x = (int) floorf(bounds.left + 0.5f);
1157                    const float y = (int) floorf(bounds.top + 0.5f);
1158                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1159                            *mSnapshot->transform);
1160                } else {
1161                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1162                            *mSnapshot->transform);
1163                }
1164            }
1165        }
1166#endif
1167
1168        if (pureTranslate) {
1169            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1170            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1171
1172            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1173                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1174                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1175                    true, !mesh->hasEmptyQuads);
1176        } else {
1177            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1178                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1179                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1180                    true, !mesh->hasEmptyQuads);
1181        }
1182    }
1183}
1184
1185void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1186    if (mSnapshot->isIgnored()) return;
1187
1188    const bool isAA = paint->isAntiAlias();
1189    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1190    // A stroke width of 0 has a special meaningin Skia:
1191    // it draws an unscaled 1px wide line
1192    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1193
1194    int alpha;
1195    SkXfermode::Mode mode;
1196    getAlphaAndMode(paint, &alpha, &mode);
1197
1198    int verticesCount = count >> 2;
1199    int generatedVerticesCount = 0;
1200    if (!isHairLine) {
1201        // TODO: AA needs more vertices
1202        verticesCount *= 6;
1203    } else {
1204        // TODO: AA will be different
1205        verticesCount *= 2;
1206    }
1207
1208    TextureVertex lines[verticesCount];
1209    TextureVertex* vertex = &lines[0];
1210
1211    setupDraw();
1212    setupDrawColor(paint->getColor(), alpha);
1213    setupDrawColorFilter();
1214    setupDrawShader();
1215    setupDrawBlending(mode);
1216    setupDrawProgram();
1217    setupDrawModelViewIdentity();
1218    setupDrawColorUniforms();
1219    setupDrawColorFilterUniforms();
1220    setupDrawShaderIdentityUniforms();
1221    setupDrawMesh(vertex);
1222
1223    if (!isHairLine) {
1224        // TODO: Handle the AA case
1225        for (int i = 0; i < count; i += 4) {
1226            // a = start point, b = end point
1227            vec2 a(points[i], points[i + 1]);
1228            vec2 b(points[i + 2], points[i + 3]);
1229
1230            // Bias to snap to the same pixels as Skia
1231            a += 0.375;
1232            b += 0.375;
1233
1234            // Find the normal to the line
1235            vec2 n = (b - a).copyNormalized() * strokeWidth;
1236            float x = n.x;
1237            n.x = -n.y;
1238            n.y = x;
1239
1240            // Four corners of the rectangle defining a thick line
1241            vec2 p1 = a - n;
1242            vec2 p2 = a + n;
1243            vec2 p3 = b + n;
1244            vec2 p4 = b - n;
1245
1246            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1247            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1248            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1249            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1250
1251            if (!quickReject(left, top, right, bottom)) {
1252                // Draw the line as 2 triangles, could be optimized
1253                // by using only 4 vertices and the correct indices
1254                // Also we should probably used non textured vertices
1255                // when line AA is disabled to save on bandwidth
1256                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1257                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1258                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1259                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1260                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1261                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1262
1263                generatedVerticesCount += 6;
1264
1265                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1266            }
1267        }
1268
1269        if (generatedVerticesCount > 0) {
1270            // GL_LINE does not give the result we want to match Skia
1271            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1272        }
1273    } else {
1274        // TODO: Handle the AA case
1275        for (int i = 0; i < count; i += 4) {
1276            const float left = fmin(points[i], points[i + 1]);
1277            const float right = fmax(points[i], points[i + 1]);
1278            const float top = fmin(points[i + 2], points[i + 3]);
1279            const float bottom = fmax(points[i + 2], points[i + 3]);
1280
1281            if (!quickReject(left, top, right, bottom)) {
1282                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1283                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1284
1285                generatedVerticesCount += 2;
1286
1287                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1288            }
1289        }
1290
1291        if (generatedVerticesCount > 0) {
1292            glLineWidth(1.0f);
1293            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1294        }
1295    }
1296}
1297
1298void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1299    // No need to check against the clip, we fill the clip region
1300    if (mSnapshot->isIgnored()) return;
1301
1302    Rect& clip(*mSnapshot->clipRect);
1303    clip.snapToPixelBoundaries();
1304
1305    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1306}
1307
1308void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1309        float rx, float ry, SkPaint* paint) {
1310    if (mSnapshot->isIgnored()) return;
1311
1312    glActiveTexture(gTextureUnits[0]);
1313
1314    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1315            right - left, bottom - top, rx, ry, paint);
1316    if (!texture) return;
1317    const AutoTexture autoCleanup(texture);
1318
1319    const float x = left + texture->left - texture->offset;
1320    const float y = top + texture->top - texture->offset;
1321
1322    drawPathTexture(texture, x, y, paint);
1323}
1324
1325void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1326    if (mSnapshot->isIgnored()) return;
1327
1328    glActiveTexture(gTextureUnits[0]);
1329
1330    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1331    if (!texture) return;
1332    const AutoTexture autoCleanup(texture);
1333
1334    const float left = (x - radius) + texture->left - texture->offset;
1335    const float top = (y - radius) + texture->top - texture->offset;
1336
1337    drawPathTexture(texture, left, top, paint);
1338}
1339
1340void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1341    if (quickReject(left, top, right, bottom)) {
1342        return;
1343    }
1344
1345    SkXfermode::Mode mode;
1346    if (!mCaches.extensions.hasFramebufferFetch()) {
1347        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1348        if (!isMode) {
1349            // Assume SRC_OVER
1350            mode = SkXfermode::kSrcOver_Mode;
1351        }
1352    } else {
1353        mode = getXfermode(p->getXfermode());
1354    }
1355
1356    // Skia draws using the color's alpha channel if < 255
1357    // Otherwise, it uses the paint's alpha
1358    int color = p->getColor();
1359    if (((color >> 24) & 0xff) == 255) {
1360        color |= p->getAlpha() << 24;
1361    }
1362
1363    drawColorRect(left, top, right, bottom, color, mode);
1364}
1365
1366void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1367        float x, float y, SkPaint* paint) {
1368    if (text == NULL || count == 0) {
1369        return;
1370    }
1371    if (mSnapshot->isIgnored()) return;
1372
1373    paint->setAntiAlias(true);
1374
1375    float length = -1.0f;
1376    switch (paint->getTextAlign()) {
1377        case SkPaint::kCenter_Align:
1378            length = paint->measureText(text, bytesCount);
1379            x -= length / 2.0f;
1380            break;
1381        case SkPaint::kRight_Align:
1382            length = paint->measureText(text, bytesCount);
1383            x -= length;
1384            break;
1385        default:
1386            break;
1387    }
1388
1389    // TODO: Handle paint->getTextScaleX()
1390    const float oldX = x;
1391    const float oldY = y;
1392    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1393    if (pureTranslate) {
1394        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1395        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1396    }
1397
1398    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1399    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1400            paint->getTextSize());
1401
1402    int alpha;
1403    SkXfermode::Mode mode;
1404    getAlphaAndMode(paint, &alpha, &mode);
1405
1406    if (mHasShadow) {
1407        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1408        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1409                count, mShadowRadius);
1410        const AutoTexture autoCleanup(shadow);
1411
1412        const float sx = x - shadow->left + mShadowDx;
1413        const float sy = y - shadow->top + mShadowDy;
1414
1415        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1416
1417        glActiveTexture(gTextureUnits[0]);
1418        setupDraw();
1419        setupDrawWithTexture(true);
1420        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1421        setupDrawBlending(true, mode);
1422        setupDrawProgram();
1423        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1424        setupDrawTexture(shadow->id);
1425        setupDrawPureColorUniforms();
1426        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1427
1428        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1429        finishDrawTexture();
1430    }
1431
1432    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1433        return;
1434    }
1435
1436    // Pick the appropriate texture filtering
1437    bool linearFilter = mSnapshot->transform->changesBounds();
1438    if (pureTranslate && !linearFilter) {
1439        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1440    }
1441
1442    glActiveTexture(gTextureUnits[0]);
1443    setupDraw();
1444    setupDrawDirtyRegionsDisabled();
1445    setupDrawWithTexture(true);
1446    setupDrawAlpha8Color(paint->getColor(), alpha);
1447    setupDrawColorFilter();
1448    setupDrawShader();
1449    setupDrawBlending(true, mode);
1450    setupDrawProgram();
1451    setupDrawModelView(x, y, x, y, pureTranslate, true);
1452    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1453    setupDrawPureColorUniforms();
1454    setupDrawColorFilterUniforms();
1455    setupDrawShaderUniforms(pureTranslate);
1456
1457    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1458    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1459
1460#if RENDER_LAYERS_AS_REGIONS
1461    bool hasActiveLayer = hasLayer();
1462#else
1463    bool hasActiveLayer = false;
1464#endif
1465
1466    mCaches.unbindMeshBuffer();
1467    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1468            hasActiveLayer ? &bounds : NULL)) {
1469#if RENDER_LAYERS_AS_REGIONS
1470        if (hasActiveLayer) {
1471            if (!pureTranslate) {
1472                mSnapshot->transform->mapRect(bounds);
1473            }
1474            dirtyLayerUnchecked(bounds, getRegion());
1475        }
1476#endif
1477    }
1478
1479    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1480    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1481
1482    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1483}
1484
1485void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1486    if (mSnapshot->isIgnored()) return;
1487
1488    glActiveTexture(gTextureUnits[0]);
1489
1490    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1491    if (!texture) return;
1492    const AutoTexture autoCleanup(texture);
1493
1494    const float x = texture->left - texture->offset;
1495    const float y = texture->top - texture->offset;
1496
1497    drawPathTexture(texture, x, y, paint);
1498}
1499
1500void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1501    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1502        return;
1503    }
1504
1505    glActiveTexture(gTextureUnits[0]);
1506
1507    int alpha;
1508    SkXfermode::Mode mode;
1509    getAlphaAndMode(paint, &alpha, &mode);
1510
1511    layer->alpha = alpha;
1512    layer->mode = mode;
1513
1514
1515#if RENDER_LAYERS_AS_REGIONS
1516    if (layer->region.isRect()) {
1517        const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1518        composeLayerRect(layer, r);
1519    } else if (!layer->region.isEmpty() && layer->mesh) {
1520        const Rect& rect = layer->layer;
1521
1522        setupDraw();
1523        setupDrawWithTexture();
1524        setupDrawColor(alpha, alpha, alpha, alpha);
1525        setupDrawColorFilter();
1526        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1527        setupDrawProgram();
1528        setupDrawDirtyRegionsDisabled();
1529        setupDrawPureColorUniforms();
1530        setupDrawColorFilterUniforms();
1531        setupDrawTexture(layer->texture);
1532        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1533        setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1534
1535        glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1536                GL_UNSIGNED_SHORT, layer->meshIndices);
1537
1538        finishDrawTexture();
1539    }
1540#else
1541    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1542    composeLayerRect(layer, r);
1543#endif
1544}
1545
1546///////////////////////////////////////////////////////////////////////////////
1547// Shaders
1548///////////////////////////////////////////////////////////////////////////////
1549
1550void OpenGLRenderer::resetShader() {
1551    mShader = NULL;
1552}
1553
1554void OpenGLRenderer::setupShader(SkiaShader* shader) {
1555    mShader = shader;
1556    if (mShader) {
1557        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1558    }
1559}
1560
1561///////////////////////////////////////////////////////////////////////////////
1562// Color filters
1563///////////////////////////////////////////////////////////////////////////////
1564
1565void OpenGLRenderer::resetColorFilter() {
1566    mColorFilter = NULL;
1567}
1568
1569void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1570    mColorFilter = filter;
1571}
1572
1573///////////////////////////////////////////////////////////////////////////////
1574// Drop shadow
1575///////////////////////////////////////////////////////////////////////////////
1576
1577void OpenGLRenderer::resetShadow() {
1578    mHasShadow = false;
1579}
1580
1581void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1582    mHasShadow = true;
1583    mShadowRadius = radius;
1584    mShadowDx = dx;
1585    mShadowDy = dy;
1586    mShadowColor = color;
1587}
1588
1589///////////////////////////////////////////////////////////////////////////////
1590// Drawing implementation
1591///////////////////////////////////////////////////////////////////////////////
1592
1593void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1594        float x, float y, SkPaint* paint) {
1595    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1596        return;
1597    }
1598
1599    int alpha;
1600    SkXfermode::Mode mode;
1601    getAlphaAndMode(paint, &alpha, &mode);
1602
1603    setupDraw();
1604    setupDrawWithTexture(true);
1605    setupDrawAlpha8Color(paint->getColor(), alpha);
1606    setupDrawColorFilter();
1607    setupDrawShader();
1608    setupDrawBlending(true, mode);
1609    setupDrawProgram();
1610    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1611    setupDrawTexture(texture->id);
1612    setupDrawPureColorUniforms();
1613    setupDrawColorFilterUniforms();
1614    setupDrawShaderUniforms();
1615    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1616
1617    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1618
1619    finishDrawTexture();
1620}
1621
1622// Same values used by Skia
1623#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1624#define kStdUnderline_Offset    (1.0f / 9.0f)
1625#define kStdUnderline_Thickness (1.0f / 18.0f)
1626
1627void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1628        float x, float y, SkPaint* paint) {
1629    // Handle underline and strike-through
1630    uint32_t flags = paint->getFlags();
1631    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1632        float underlineWidth = length;
1633        // If length is > 0.0f, we already measured the text for the text alignment
1634        if (length <= 0.0f) {
1635            underlineWidth = paint->measureText(text, bytesCount);
1636        }
1637
1638        float offsetX = 0;
1639        switch (paint->getTextAlign()) {
1640            case SkPaint::kCenter_Align:
1641                offsetX = underlineWidth * 0.5f;
1642                break;
1643            case SkPaint::kRight_Align:
1644                offsetX = underlineWidth;
1645                break;
1646            default:
1647                break;
1648        }
1649
1650        if (underlineWidth > 0.0f) {
1651            const float textSize = paint->getTextSize();
1652            const float strokeWidth = textSize * kStdUnderline_Thickness;
1653
1654            const float left = x - offsetX;
1655            float top = 0.0f;
1656
1657            const int pointsCount = 4 * (flags & SkPaint::kStrikeThruText_Flag ? 2 : 1);
1658            float points[pointsCount];
1659            int currentPoint = 0;
1660
1661            if (flags & SkPaint::kUnderlineText_Flag) {
1662                top = y + textSize * kStdUnderline_Offset;
1663                points[currentPoint++] = left;
1664                points[currentPoint++] = top;
1665                points[currentPoint++] = left + underlineWidth;
1666                points[currentPoint++] = top;
1667            }
1668
1669            if (flags & SkPaint::kStrikeThruText_Flag) {
1670                top = y + textSize * kStdStrikeThru_Offset;
1671                points[currentPoint++] = left;
1672                points[currentPoint++] = top;
1673                points[currentPoint++] = left + underlineWidth;
1674                points[currentPoint++] = top;
1675            }
1676
1677            SkPaint linesPaint(*paint);
1678            linesPaint.setStrokeWidth(strokeWidth);
1679
1680            drawLines(&points[0], pointsCount, &linesPaint);
1681        }
1682    }
1683}
1684
1685void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1686        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1687    // If a shader is set, preserve only the alpha
1688    if (mShader) {
1689        color |= 0x00ffffff;
1690    }
1691
1692    setupDraw();
1693    setupDrawColor(color);
1694    setupDrawShader();
1695    setupDrawColorFilter();
1696    setupDrawBlending(mode);
1697    setupDrawProgram();
1698    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1699    setupDrawColorUniforms();
1700    setupDrawShaderUniforms(ignoreTransform);
1701    setupDrawColorFilterUniforms();
1702    setupDrawSimpleMesh();
1703
1704    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1705}
1706
1707void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1708        Texture* texture, SkPaint* paint) {
1709    int alpha;
1710    SkXfermode::Mode mode;
1711    getAlphaAndMode(paint, &alpha, &mode);
1712
1713    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1714
1715    if (mSnapshot->transform->isPureTranslate()) {
1716        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1717        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1718
1719        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1720                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1721                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1722    } else {
1723        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1724                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1725                GL_TRIANGLE_STRIP, gMeshCount);
1726    }
1727}
1728
1729void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1730        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1731    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1732            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1733}
1734
1735void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1736        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1737        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1738        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1739
1740    setupDraw();
1741    setupDrawWithTexture();
1742    setupDrawColor(alpha, alpha, alpha, alpha);
1743    setupDrawColorFilter();
1744    setupDrawBlending(blend, mode, swapSrcDst);
1745    setupDrawProgram();
1746    if (!dirty) {
1747        setupDrawDirtyRegionsDisabled();
1748    }
1749    if (!ignoreScale) {
1750        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1751    } else {
1752        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1753    }
1754    setupDrawPureColorUniforms();
1755    setupDrawColorFilterUniforms();
1756    setupDrawTexture(texture);
1757    setupDrawMesh(vertices, texCoords, vbo);
1758
1759    glDrawArrays(drawMode, 0, elementsCount);
1760
1761    finishDrawTexture();
1762}
1763
1764void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1765        ProgramDescription& description, bool swapSrcDst) {
1766    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1767    if (blend) {
1768        if (mode < SkXfermode::kPlus_Mode) {
1769            if (!mCaches.blend) {
1770                glEnable(GL_BLEND);
1771            }
1772
1773            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1774            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1775
1776            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1777                glBlendFunc(sourceMode, destMode);
1778                mCaches.lastSrcMode = sourceMode;
1779                mCaches.lastDstMode = destMode;
1780            }
1781        } else {
1782            // These blend modes are not supported by OpenGL directly and have
1783            // to be implemented using shaders. Since the shader will perform
1784            // the blending, turn blending off here
1785            if (mCaches.extensions.hasFramebufferFetch()) {
1786                description.framebufferMode = mode;
1787                description.swapSrcDst = swapSrcDst;
1788            }
1789
1790            if (mCaches.blend) {
1791                glDisable(GL_BLEND);
1792            }
1793            blend = false;
1794        }
1795    } else if (mCaches.blend) {
1796        glDisable(GL_BLEND);
1797    }
1798    mCaches.blend = blend;
1799}
1800
1801bool OpenGLRenderer::useProgram(Program* program) {
1802    if (!program->isInUse()) {
1803        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1804        program->use();
1805        mCaches.currentProgram = program;
1806        return false;
1807    }
1808    return true;
1809}
1810
1811void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1812    TextureVertex* v = &mMeshVertices[0];
1813    TextureVertex::setUV(v++, u1, v1);
1814    TextureVertex::setUV(v++, u2, v1);
1815    TextureVertex::setUV(v++, u1, v2);
1816    TextureVertex::setUV(v++, u2, v2);
1817}
1818
1819void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1820    if (paint) {
1821        if (!mCaches.extensions.hasFramebufferFetch()) {
1822            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1823            if (!isMode) {
1824                // Assume SRC_OVER
1825                *mode = SkXfermode::kSrcOver_Mode;
1826            }
1827        } else {
1828            *mode = getXfermode(paint->getXfermode());
1829        }
1830
1831        // Skia draws using the color's alpha channel if < 255
1832        // Otherwise, it uses the paint's alpha
1833        int color = paint->getColor();
1834        *alpha = (color >> 24) & 0xFF;
1835        if (*alpha == 255) {
1836            *alpha = paint->getAlpha();
1837        }
1838    } else {
1839        *mode = SkXfermode::kSrcOver_Mode;
1840        *alpha = 255;
1841    }
1842}
1843
1844SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1845    if (mode == NULL) {
1846        return SkXfermode::kSrcOver_Mode;
1847    }
1848    return mode->fMode;
1849}
1850
1851void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1852    bool bound = false;
1853    if (wrapS != texture->wrapS) {
1854        glBindTexture(GL_TEXTURE_2D, texture->id);
1855        bound = true;
1856        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1857        texture->wrapS = wrapS;
1858    }
1859    if (wrapT != texture->wrapT) {
1860        if (!bound) {
1861            glBindTexture(GL_TEXTURE_2D, texture->id);
1862        }
1863        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1864        texture->wrapT = wrapT;
1865    }
1866}
1867
1868}; // namespace uirenderer
1869}; // namespace android
1870