OpenGLRenderer.cpp revision 01d58e43ede5ca98cbebdd166f9b0c545032c01b 
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
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
443        // Enqueue the buffer coordinates to clear the corresponding region later
444        mLayers.push(new Rect(bounds));
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        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
569        composeLayerRect(layer, rect, true);
570    }
571
572    if (fboLayer) {
573        // Detach the texture from the FBO
574        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
575        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
576        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
577
578        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
579        mCaches.fboCache.put(current->fbo);
580    }
581
582    dirtyClip();
583
584    // Failing to add the layer to the cache should happen only if the layer is too large
585    if (!mCaches.layerCache.put(layer)) {
586        LAYER_LOGD("Deleting layer");
587        glDeleteTextures(1, &layer->texture);
588        delete layer;
589    }
590}
591
592void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
593    const Rect& texCoords = layer->texCoords;
594    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
595
596    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
597            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
598            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
599
600    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
601}
602
603void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
604#if RENDER_LAYERS_AS_REGIONS
605    if (layer->region.isRect()) {
606        composeLayerRect(layer, rect);
607        layer->region.clear();
608        return;
609    }
610
611    if (!layer->region.isEmpty()) {
612        size_t count;
613        const android::Rect* rects = layer->region.getArray(&count);
614
615        const float alpha = layer->alpha / 255.0f;
616        const float texX = 1.0f / float(layer->width);
617        const float texY = 1.0f / float(layer->height);
618        const float height = rect.getHeight();
619
620        TextureVertex* mesh = mCaches.getRegionMesh();
621        GLsizei numQuads = 0;
622
623        setupDraw();
624        setupDrawWithTexture();
625        setupDrawColor(alpha, alpha, alpha, alpha);
626        setupDrawColorFilter();
627        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
628        setupDrawProgram();
629        setupDrawDirtyRegionsDisabled();
630        setupDrawPureColorUniforms();
631        setupDrawColorFilterUniforms();
632        setupDrawTexture(layer->texture);
633        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
634        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
635
636        for (size_t i = 0; i < count; i++) {
637            const android::Rect* r = &rects[i];
638
639            const float u1 = r->left * texX;
640            const float v1 = (height - r->top) * texY;
641            const float u2 = r->right * texX;
642            const float v2 = (height - r->bottom) * texY;
643
644            // TODO: Reject quads outside of the clip
645            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
646            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
647            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
648            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
649
650            numQuads++;
651
652            if (numQuads >= REGION_MESH_QUAD_COUNT) {
653                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
654                numQuads = 0;
655                mesh = mCaches.getRegionMesh();
656            }
657        }
658
659        if (numQuads > 0) {
660            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
661        }
662
663        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
664        finishDrawTexture();
665
666#if DEBUG_LAYERS_AS_REGIONS
667        uint32_t colors[] = {
668                0x7fff0000, 0x7f00ff00,
669                0x7f0000ff, 0x7fff00ff,
670        };
671
672        int offset = 0;
673        int32_t top = rects[0].top;
674        int i = 0;
675
676        for (size_t i = 0; i < count; i++) {
677            if (top != rects[i].top) {
678                offset ^= 0x2;
679                top = rects[i].top;
680            }
681
682            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
683            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
684                    SkXfermode::kSrcOver_Mode);
685        }
686#endif
687
688        layer->region.clear();
689    }
690#else
691    composeLayerRect(layer, rect);
692#endif
693}
694
695void OpenGLRenderer::dirtyLayer(const float left, const float top,
696        const float right, const float bottom, const mat4 transform) {
697#if RENDER_LAYERS_AS_REGIONS
698    if (hasLayer()) {
699        Rect bounds(left, top, right, bottom);
700        transform.mapRect(bounds);
701        dirtyLayerUnchecked(bounds, getRegion());
702    }
703#endif
704}
705
706void OpenGLRenderer::dirtyLayer(const float left, const float top,
707        const float right, const float bottom) {
708#if RENDER_LAYERS_AS_REGIONS
709    if (hasLayer()) {
710        Rect bounds(left, top, right, bottom);
711        dirtyLayerUnchecked(bounds, getRegion());
712    }
713#endif
714}
715
716void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
717#if RENDER_LAYERS_AS_REGIONS
718    if (bounds.intersect(*mSnapshot->clipRect)) {
719        bounds.snapToPixelBoundaries();
720        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
721        if (!dirty.isEmpty()) {
722            region->orSelf(dirty);
723        }
724    }
725#endif
726}
727
728void OpenGLRenderer::clearLayerRegions() {
729    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
730
731    Rect clipRect(*mSnapshot->clipRect);
732    clipRect.snapToPixelBoundaries();
733
734    for (uint32_t i = 0; i < mLayers.size(); i++) {
735        Rect* bounds = mLayers.itemAt(i);
736        if (clipRect.intersects(*bounds)) {
737            // Clear the framebuffer where the layer will draw
738            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
739                    bounds->getWidth(), bounds->getHeight());
740            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
741            glClear(GL_COLOR_BUFFER_BIT);
742
743            // Restore the clip
744            dirtyClip();
745        }
746
747        delete bounds;
748    }
749
750    mLayers.clear();
751}
752
753///////////////////////////////////////////////////////////////////////////////
754// Transforms
755///////////////////////////////////////////////////////////////////////////////
756
757void OpenGLRenderer::translate(float dx, float dy) {
758    mSnapshot->transform->translate(dx, dy, 0.0f);
759}
760
761void OpenGLRenderer::rotate(float degrees) {
762    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
763}
764
765void OpenGLRenderer::scale(float sx, float sy) {
766    mSnapshot->transform->scale(sx, sy, 1.0f);
767}
768
769void OpenGLRenderer::skew(float sx, float sy) {
770    mSnapshot->transform->skew(sx, sy);
771}
772
773void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
774    mSnapshot->transform->load(*matrix);
775}
776
777const float* OpenGLRenderer::getMatrix() const {
778    if (mSnapshot->fbo != 0) {
779        return &mSnapshot->transform->data[0];
780    }
781    return &mIdentity.data[0];
782}
783
784void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
785    mSnapshot->transform->copyTo(*matrix);
786}
787
788void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
789    SkMatrix transform;
790    mSnapshot->transform->copyTo(transform);
791    transform.preConcat(*matrix);
792    mSnapshot->transform->load(transform);
793}
794
795///////////////////////////////////////////////////////////////////////////////
796// Clipping
797///////////////////////////////////////////////////////////////////////////////
798
799void OpenGLRenderer::setScissorFromClip() {
800    Rect clip(*mSnapshot->clipRect);
801    clip.snapToPixelBoundaries();
802    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
803    mDirtyClip = false;
804}
805
806const Rect& OpenGLRenderer::getClipBounds() {
807    return mSnapshot->getLocalClip();
808}
809
810bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
811    if (mSnapshot->isIgnored()) {
812        return true;
813    }
814
815    Rect r(left, top, right, bottom);
816    mSnapshot->transform->mapRect(r);
817    r.snapToPixelBoundaries();
818
819    Rect clipRect(*mSnapshot->clipRect);
820    clipRect.snapToPixelBoundaries();
821
822    return !clipRect.intersects(r);
823}
824
825bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
826    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
827    if (clipped) {
828        dirtyClip();
829    }
830    return !mSnapshot->clipRect->isEmpty();
831}
832
833///////////////////////////////////////////////////////////////////////////////
834// Drawing commands
835///////////////////////////////////////////////////////////////////////////////
836
837void OpenGLRenderer::setupDraw() {
838    clearLayerRegions();
839    if (mDirtyClip) {
840        setScissorFromClip();
841    }
842    mDescription.reset();
843    mSetShaderColor = false;
844    mColorSet = false;
845    mColorA = mColorR = mColorG = mColorB = 0.0f;
846    mTextureUnit = 0;
847    mTrackDirtyRegions = true;
848    mTexCoordsSlot = -1;
849}
850
851void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
852    mDescription.hasTexture = true;
853    mDescription.hasAlpha8Texture = isAlpha8;
854}
855
856void OpenGLRenderer::setupDrawColor(int color) {
857    setupDrawColor(color, (color >> 24) & 0xFF);
858}
859
860void OpenGLRenderer::setupDrawColor(int color, int alpha) {
861    mColorA = alpha / 255.0f;
862    const float a = mColorA / 255.0f;
863    mColorR = a * ((color >> 16) & 0xFF);
864    mColorG = a * ((color >>  8) & 0xFF);
865    mColorB = a * ((color      ) & 0xFF);
866    mColorSet = true;
867    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
868}
869
870void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
871    mColorA = alpha / 255.0f;
872    const float a = mColorA / 255.0f;
873    mColorR = a * ((color >> 16) & 0xFF);
874    mColorG = a * ((color >>  8) & 0xFF);
875    mColorB = a * ((color      ) & 0xFF);
876    mColorSet = true;
877    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
878}
879
880void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
881    mColorA = a;
882    mColorR = r;
883    mColorG = g;
884    mColorB = b;
885    mColorSet = true;
886    mSetShaderColor = mDescription.setColor(r, g, b, a);
887}
888
889void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
890    mColorA = a;
891    mColorR = r;
892    mColorG = g;
893    mColorB = b;
894    mColorSet = true;
895    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
896}
897
898void OpenGLRenderer::setupDrawShader() {
899    if (mShader) {
900        mShader->describe(mDescription, mCaches.extensions);
901    }
902}
903
904void OpenGLRenderer::setupDrawColorFilter() {
905    if (mColorFilter) {
906        mColorFilter->describe(mDescription, mCaches.extensions);
907    }
908}
909
910void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
911    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
912            mDescription, swapSrcDst);
913}
914
915void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
916    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
917            mDescription, swapSrcDst);
918}
919
920void OpenGLRenderer::setupDrawProgram() {
921    useProgram(mCaches.programCache.get(mDescription));
922}
923
924void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
925    mTrackDirtyRegions = false;
926}
927
928void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
929        bool ignoreTransform) {
930    mModelView.loadTranslate(left, top, 0.0f);
931    if (!ignoreTransform) {
932        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
933        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
934    } else {
935        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
936        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
937    }
938}
939
940void OpenGLRenderer::setupDrawModelViewIdentity() {
941    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
942}
943
944void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
945        bool ignoreTransform, bool ignoreModelView) {
946    if (!ignoreModelView) {
947        mModelView.loadTranslate(left, top, 0.0f);
948        mModelView.scale(right - left, bottom - top, 1.0f);
949    } else {
950        mModelView.loadIdentity();
951    }
952    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
953    if (!ignoreTransform) {
954        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
955        if (mTrackDirtyRegions && dirty) {
956            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
957        }
958    } else {
959        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
960        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
961    }
962}
963
964void OpenGLRenderer::setupDrawColorUniforms() {
965    if (mColorSet || (mShader && mSetShaderColor)) {
966        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
967    }
968}
969
970void OpenGLRenderer::setupDrawPureColorUniforms() {
971    if (mSetShaderColor) {
972        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
973    }
974}
975
976void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
977    if (mShader) {
978        if (ignoreTransform) {
979            mModelView.loadInverse(*mSnapshot->transform);
980        }
981        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
982    }
983}
984
985void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
986    if (mShader) {
987        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
988    }
989}
990
991void OpenGLRenderer::setupDrawColorFilterUniforms() {
992    if (mColorFilter) {
993        mColorFilter->setupProgram(mCaches.currentProgram);
994    }
995}
996
997void OpenGLRenderer::setupDrawSimpleMesh() {
998    mCaches.bindMeshBuffer();
999    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1000            gMeshStride, 0);
1001}
1002
1003void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1004    bindTexture(texture);
1005    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1006
1007    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1008    glEnableVertexAttribArray(mTexCoordsSlot);
1009}
1010
1011void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1012    if (!vertices) {
1013        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1014    } else {
1015        mCaches.unbindMeshBuffer();
1016    }
1017    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1018            gMeshStride, vertices);
1019    if (mTexCoordsSlot > 0) {
1020        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1021    }
1022}
1023
1024void OpenGLRenderer::finishDrawTexture() {
1025    glDisableVertexAttribArray(mTexCoordsSlot);
1026}
1027
1028///////////////////////////////////////////////////////////////////////////////
1029// Drawing
1030///////////////////////////////////////////////////////////////////////////////
1031
1032void OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t level) {
1033    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1034    // will be performed by the display list itself
1035    if (displayList) {
1036        displayList->replay(*this, level);
1037    }
1038}
1039
1040void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1041    const float right = left + bitmap->width();
1042    const float bottom = top + bitmap->height();
1043
1044    if (quickReject(left, top, right, bottom)) {
1045        return;
1046    }
1047
1048    glActiveTexture(gTextureUnits[0]);
1049    Texture* texture = mCaches.textureCache.get(bitmap);
1050    if (!texture) return;
1051    const AutoTexture autoCleanup(texture);
1052
1053    drawTextureRect(left, top, right, bottom, texture, paint);
1054}
1055
1056void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1057    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1058    const mat4 transform(*matrix);
1059    transform.mapRect(r);
1060
1061    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1062        return;
1063    }
1064
1065    glActiveTexture(gTextureUnits[0]);
1066    Texture* texture = mCaches.textureCache.get(bitmap);
1067    if (!texture) return;
1068    const AutoTexture autoCleanup(texture);
1069
1070    // This could be done in a cheaper way, all we need is pass the matrix
1071    // to the vertex shader. The save/restore is a bit overkill.
1072    save(SkCanvas::kMatrix_SaveFlag);
1073    concatMatrix(matrix);
1074    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1075    restore();
1076}
1077
1078void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1079         float srcLeft, float srcTop, float srcRight, float srcBottom,
1080         float dstLeft, float dstTop, float dstRight, float dstBottom,
1081         SkPaint* paint) {
1082    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1083        return;
1084    }
1085
1086    glActiveTexture(gTextureUnits[0]);
1087    Texture* texture = mCaches.textureCache.get(bitmap);
1088    if (!texture) return;
1089    const AutoTexture autoCleanup(texture);
1090    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1091
1092    const float width = texture->width;
1093    const float height = texture->height;
1094
1095    const float u1 = srcLeft / width;
1096    const float v1 = srcTop / height;
1097    const float u2 = srcRight / width;
1098    const float v2 = srcBottom / height;
1099
1100    mCaches.unbindMeshBuffer();
1101    resetDrawTextureTexCoords(u1, v1, u2, v2);
1102
1103    int alpha;
1104    SkXfermode::Mode mode;
1105    getAlphaAndMode(paint, &alpha, &mode);
1106
1107    if (mSnapshot->transform->isPureTranslate()) {
1108        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1109        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1110
1111        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1112                texture->id, alpha / 255.0f, mode, texture->blend,
1113                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1114                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1115    } else {
1116        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1117                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1118                GL_TRIANGLE_STRIP, gMeshCount);
1119    }
1120
1121    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1122}
1123
1124void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1125        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1126        float left, float top, float right, float bottom, SkPaint* paint) {
1127    if (quickReject(left, top, right, bottom)) {
1128        return;
1129    }
1130
1131    glActiveTexture(gTextureUnits[0]);
1132    Texture* texture = mCaches.textureCache.get(bitmap);
1133    if (!texture) return;
1134    const AutoTexture autoCleanup(texture);
1135    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1136
1137    int alpha;
1138    SkXfermode::Mode mode;
1139    getAlphaAndMode(paint, &alpha, &mode);
1140
1141    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1142            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1143
1144    if (mesh && mesh->verticesCount > 0) {
1145        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1146#if RENDER_LAYERS_AS_REGIONS
1147        // Mark the current layer dirty where we are going to draw the patch
1148        if ((mSnapshot->flags & Snapshot::kFlagFboTarget) &&
1149                mSnapshot->region && mesh->hasEmptyQuads) {
1150            const size_t count = mesh->quads.size();
1151            for (size_t i = 0; i < count; i++) {
1152                const Rect& bounds = mesh->quads.itemAt(i);
1153                if (pureTranslate) {
1154                    const float x = (int) floorf(bounds.left + 0.5f);
1155                    const float y = (int) floorf(bounds.top + 0.5f);
1156                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1157                            *mSnapshot->transform);
1158                } else {
1159                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1160                            *mSnapshot->transform);
1161                }
1162            }
1163        }
1164#endif
1165
1166        if (pureTranslate) {
1167            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1168            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1169
1170            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1171                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1172                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1173                    true, !mesh->hasEmptyQuads);
1174        } else {
1175            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1176                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1177                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1178                    true, !mesh->hasEmptyQuads);
1179        }
1180    }
1181}
1182
1183void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1184    if (mSnapshot->isIgnored()) return;
1185
1186    const bool isAA = paint->isAntiAlias();
1187    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1188    // A stroke width of 0 has a special meaningin Skia:
1189    // it draws an unscaled 1px wide line
1190    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1191
1192    int alpha;
1193    SkXfermode::Mode mode;
1194    getAlphaAndMode(paint, &alpha, &mode);
1195
1196    int verticesCount = count >> 2;
1197    int generatedVerticesCount = 0;
1198    if (!isHairLine) {
1199        // TODO: AA needs more vertices
1200        verticesCount *= 6;
1201    } else {
1202        // TODO: AA will be different
1203        verticesCount *= 2;
1204    }
1205
1206    TextureVertex lines[verticesCount];
1207    TextureVertex* vertex = &lines[0];
1208
1209    setupDraw();
1210    setupDrawColor(paint->getColor(), alpha);
1211    setupDrawColorFilter();
1212    setupDrawShader();
1213    setupDrawBlending(mode);
1214    setupDrawProgram();
1215    setupDrawModelViewIdentity();
1216    setupDrawColorUniforms();
1217    setupDrawColorFilterUniforms();
1218    setupDrawShaderIdentityUniforms();
1219    setupDrawMesh(vertex);
1220
1221    if (!isHairLine) {
1222        // TODO: Handle the AA case
1223        for (int i = 0; i < count; i += 4) {
1224            // a = start point, b = end point
1225            vec2 a(points[i], points[i + 1]);
1226            vec2 b(points[i + 2], points[i + 3]);
1227
1228            // Bias to snap to the same pixels as Skia
1229            a += 0.375;
1230            b += 0.375;
1231
1232            // Find the normal to the line
1233            vec2 n = (b - a).copyNormalized() * strokeWidth;
1234            float x = n.x;
1235            n.x = -n.y;
1236            n.y = x;
1237
1238            // Four corners of the rectangle defining a thick line
1239            vec2 p1 = a - n;
1240            vec2 p2 = a + n;
1241            vec2 p3 = b + n;
1242            vec2 p4 = b - n;
1243
1244            const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1245            const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1246            const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1247            const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1248
1249            if (!quickReject(left, top, right, bottom)) {
1250                // Draw the line as 2 triangles, could be optimized
1251                // by using only 4 vertices and the correct indices
1252                // Also we should probably used non textured vertices
1253                // when line AA is disabled to save on bandwidth
1254                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1255                TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1256                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1257                TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1258                TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1259                TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1260
1261                generatedVerticesCount += 6;
1262
1263                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1264            }
1265        }
1266
1267        if (generatedVerticesCount > 0) {
1268            // GL_LINE does not give the result we want to match Skia
1269            glDrawArrays(GL_TRIANGLES, 0, generatedVerticesCount);
1270        }
1271    } else {
1272        // TODO: Handle the AA case
1273        for (int i = 0; i < count; i += 4) {
1274            const float left = fmin(points[i], points[i + 1]);
1275            const float right = fmax(points[i], points[i + 1]);
1276            const float top = fmin(points[i + 2], points[i + 3]);
1277            const float bottom = fmax(points[i + 2], points[i + 3]);
1278
1279            if (!quickReject(left, top, right, bottom)) {
1280                TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1281                TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1282
1283                generatedVerticesCount += 2;
1284
1285                dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1286            }
1287        }
1288
1289        if (generatedVerticesCount > 0) {
1290            glLineWidth(1.0f);
1291            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1292        }
1293    }
1294}
1295
1296void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1297    // No need to check against the clip, we fill the clip region
1298    if (mSnapshot->isIgnored()) return;
1299
1300    Rect& clip(*mSnapshot->clipRect);
1301    clip.snapToPixelBoundaries();
1302
1303    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1304}
1305
1306void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1307        float rx, float ry, SkPaint* paint) {
1308    if (mSnapshot->isIgnored()) return;
1309
1310    glActiveTexture(gTextureUnits[0]);
1311
1312    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1313            right - left, bottom - top, rx, ry, paint);
1314    if (!texture) return;
1315    const AutoTexture autoCleanup(texture);
1316
1317    const float x = left + texture->left - texture->offset;
1318    const float y = top + texture->top - texture->offset;
1319
1320    drawPathTexture(texture, x, y, paint);
1321}
1322
1323void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1324    if (mSnapshot->isIgnored()) return;
1325
1326    glActiveTexture(gTextureUnits[0]);
1327
1328    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1329    if (!texture) return;
1330    const AutoTexture autoCleanup(texture);
1331
1332    const float left = (x - radius) + texture->left - texture->offset;
1333    const float top = (y - radius) + texture->top - texture->offset;
1334
1335    drawPathTexture(texture, left, top, paint);
1336}
1337
1338void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1339    if (quickReject(left, top, right, bottom)) {
1340        return;
1341    }
1342
1343    SkXfermode::Mode mode;
1344    if (!mCaches.extensions.hasFramebufferFetch()) {
1345        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1346        if (!isMode) {
1347            // Assume SRC_OVER
1348            mode = SkXfermode::kSrcOver_Mode;
1349        }
1350    } else {
1351        mode = getXfermode(p->getXfermode());
1352    }
1353
1354    // Skia draws using the color's alpha channel if < 255
1355    // Otherwise, it uses the paint's alpha
1356    int color = p->getColor();
1357    if (((color >> 24) & 0xff) == 255) {
1358        color |= p->getAlpha() << 24;
1359    }
1360
1361    drawColorRect(left, top, right, bottom, color, mode);
1362}
1363
1364void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1365        float x, float y, SkPaint* paint) {
1366    if (text == NULL || count == 0) {
1367        return;
1368    }
1369    if (mSnapshot->isIgnored()) return;
1370
1371    paint->setAntiAlias(true);
1372
1373    float length = -1.0f;
1374    switch (paint->getTextAlign()) {
1375        case SkPaint::kCenter_Align:
1376            length = paint->measureText(text, bytesCount);
1377            x -= length / 2.0f;
1378            break;
1379        case SkPaint::kRight_Align:
1380            length = paint->measureText(text, bytesCount);
1381            x -= length;
1382            break;
1383        default:
1384            break;
1385    }
1386
1387    // TODO: Handle paint->getTextScaleX()
1388    const float oldX = x;
1389    const float oldY = y;
1390    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1391    if (pureTranslate) {
1392        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1393        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1394    }
1395
1396    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1397    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1398            paint->getTextSize());
1399
1400    int alpha;
1401    SkXfermode::Mode mode;
1402    getAlphaAndMode(paint, &alpha, &mode);
1403
1404    if (mHasShadow) {
1405        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1406        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1407                count, mShadowRadius);
1408        const AutoTexture autoCleanup(shadow);
1409
1410        const float sx = x - shadow->left + mShadowDx;
1411        const float sy = y - shadow->top + mShadowDy;
1412
1413        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1414
1415        glActiveTexture(gTextureUnits[0]);
1416        setupDraw();
1417        setupDrawWithTexture(true);
1418        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1419        setupDrawBlending(true, mode);
1420        setupDrawProgram();
1421        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1422        setupDrawTexture(shadow->id);
1423        setupDrawPureColorUniforms();
1424        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1425
1426        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1427        finishDrawTexture();
1428    }
1429
1430    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1431        return;
1432    }
1433
1434    // Pick the appropriate texture filtering
1435    bool linearFilter = mSnapshot->transform->changesBounds();
1436    if (pureTranslate && !linearFilter) {
1437        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1438    }
1439
1440    glActiveTexture(gTextureUnits[0]);
1441    setupDraw();
1442    setupDrawDirtyRegionsDisabled();
1443    setupDrawWithTexture(true);
1444    setupDrawAlpha8Color(paint->getColor(), alpha);
1445    setupDrawColorFilter();
1446    setupDrawShader();
1447    setupDrawBlending(true, mode);
1448    setupDrawProgram();
1449    setupDrawModelView(x, y, x, y, pureTranslate, true);
1450    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1451    setupDrawPureColorUniforms();
1452    setupDrawColorFilterUniforms();
1453    setupDrawShaderUniforms(pureTranslate);
1454
1455    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1456    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1457
1458#if RENDER_LAYERS_AS_REGIONS
1459    bool hasActiveLayer = hasLayer();
1460#else
1461    bool hasActiveLayer = false;
1462#endif
1463
1464    mCaches.unbindMeshBuffer();
1465    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1466            hasActiveLayer ? &bounds : NULL)) {
1467#if RENDER_LAYERS_AS_REGIONS
1468        if (hasActiveLayer) {
1469            if (!pureTranslate) {
1470                mSnapshot->transform->mapRect(bounds);
1471            }
1472            dirtyLayerUnchecked(bounds, getRegion());
1473        }
1474#endif
1475    }
1476
1477    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1478    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1479
1480    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1481}
1482
1483void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1484    if (mSnapshot->isIgnored()) return;
1485
1486    glActiveTexture(gTextureUnits[0]);
1487
1488    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1489    if (!texture) return;
1490    const AutoTexture autoCleanup(texture);
1491
1492    const float x = texture->left - texture->offset;
1493    const float y = texture->top - texture->offset;
1494
1495    drawPathTexture(texture, x, y, paint);
1496}
1497
1498void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1499    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1500        return;
1501    }
1502
1503    glActiveTexture(gTextureUnits[0]);
1504
1505    int alpha;
1506    SkXfermode::Mode mode;
1507    getAlphaAndMode(paint, &alpha, &mode);
1508
1509    layer->alpha = alpha;
1510    layer->mode = mode;
1511
1512
1513#if RENDER_LAYERS_AS_REGIONS
1514    if (layer->region.isRect()) {
1515        const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1516        composeLayerRect(layer, r);
1517    } else if (!layer->region.isEmpty() && layer->mesh) {
1518        const Rect& rect = layer->layer;
1519
1520        setupDraw();
1521        setupDrawWithTexture();
1522        setupDrawColor(alpha, alpha, alpha, alpha);
1523        setupDrawColorFilter();
1524        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1525        setupDrawProgram();
1526        setupDrawDirtyRegionsDisabled();
1527        setupDrawPureColorUniforms();
1528        setupDrawColorFilterUniforms();
1529        setupDrawTexture(layer->texture);
1530        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
1531        setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1532
1533        glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1534                GL_UNSIGNED_SHORT, layer->meshIndices);
1535
1536        finishDrawTexture();
1537    }
1538#else
1539    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1540    composeLayerRect(layer, r);
1541#endif
1542}
1543
1544///////////////////////////////////////////////////////////////////////////////
1545// Shaders
1546///////////////////////////////////////////////////////////////////////////////
1547
1548void OpenGLRenderer::resetShader() {
1549    mShader = NULL;
1550}
1551
1552void OpenGLRenderer::setupShader(SkiaShader* shader) {
1553    mShader = shader;
1554    if (mShader) {
1555        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1556    }
1557}
1558
1559///////////////////////////////////////////////////////////////////////////////
1560// Color filters
1561///////////////////////////////////////////////////////////////////////////////
1562
1563void OpenGLRenderer::resetColorFilter() {
1564    mColorFilter = NULL;
1565}
1566
1567void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1568    mColorFilter = filter;
1569}
1570
1571///////////////////////////////////////////////////////////////////////////////
1572// Drop shadow
1573///////////////////////////////////////////////////////////////////////////////
1574
1575void OpenGLRenderer::resetShadow() {
1576    mHasShadow = false;
1577}
1578
1579void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1580    mHasShadow = true;
1581    mShadowRadius = radius;
1582    mShadowDx = dx;
1583    mShadowDy = dy;
1584    mShadowColor = color;
1585}
1586
1587///////////////////////////////////////////////////////////////////////////////
1588// Drawing implementation
1589///////////////////////////////////////////////////////////////////////////////
1590
1591void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1592        float x, float y, SkPaint* paint) {
1593    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1594        return;
1595    }
1596
1597    int alpha;
1598    SkXfermode::Mode mode;
1599    getAlphaAndMode(paint, &alpha, &mode);
1600
1601    setupDraw();
1602    setupDrawWithTexture(true);
1603    setupDrawAlpha8Color(paint->getColor(), alpha);
1604    setupDrawColorFilter();
1605    setupDrawShader();
1606    setupDrawBlending(true, mode);
1607    setupDrawProgram();
1608    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1609    setupDrawTexture(texture->id);
1610    setupDrawPureColorUniforms();
1611    setupDrawColorFilterUniforms();
1612    setupDrawShaderUniforms();
1613    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1614
1615    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1616
1617    finishDrawTexture();
1618}
1619
1620// Same values used by Skia
1621#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1622#define kStdUnderline_Offset    (1.0f / 9.0f)
1623#define kStdUnderline_Thickness (1.0f / 18.0f)
1624
1625void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1626        float x, float y, SkPaint* paint) {
1627    // Handle underline and strike-through
1628    uint32_t flags = paint->getFlags();
1629    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1630        float underlineWidth = length;
1631        // If length is > 0.0f, we already measured the text for the text alignment
1632        if (length <= 0.0f) {
1633            underlineWidth = paint->measureText(text, bytesCount);
1634        }
1635
1636        float offsetX = 0;
1637        switch (paint->getTextAlign()) {
1638            case SkPaint::kCenter_Align:
1639                offsetX = underlineWidth * 0.5f;
1640                break;
1641            case SkPaint::kRight_Align:
1642                offsetX = underlineWidth;
1643                break;
1644            default:
1645                break;
1646        }
1647
1648        if (underlineWidth > 0.0f) {
1649            const float textSize = paint->getTextSize();
1650            const float strokeWidth = textSize * kStdUnderline_Thickness;
1651
1652            const float left = x - offsetX;
1653            float top = 0.0f;
1654
1655            const int pointsCount = 4 * (flags & SkPaint::kStrikeThruText_Flag ? 2 : 1);
1656            float points[pointsCount];
1657            int currentPoint = 0;
1658
1659            if (flags & SkPaint::kUnderlineText_Flag) {
1660                top = y + textSize * kStdUnderline_Offset;
1661                points[currentPoint++] = left;
1662                points[currentPoint++] = top;
1663                points[currentPoint++] = left + underlineWidth;
1664                points[currentPoint++] = top;
1665            }
1666
1667            if (flags & SkPaint::kStrikeThruText_Flag) {
1668                top = y + textSize * kStdStrikeThru_Offset;
1669                points[currentPoint++] = left;
1670                points[currentPoint++] = top;
1671                points[currentPoint++] = left + underlineWidth;
1672                points[currentPoint++] = top;
1673            }
1674
1675            SkPaint linesPaint(*paint);
1676            linesPaint.setStrokeWidth(strokeWidth);
1677
1678            drawLines(&points[0], pointsCount, &linesPaint);
1679        }
1680    }
1681}
1682
1683void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1684        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1685    // If a shader is set, preserve only the alpha
1686    if (mShader) {
1687        color |= 0x00ffffff;
1688    }
1689
1690    setupDraw();
1691    setupDrawColor(color);
1692    setupDrawShader();
1693    setupDrawColorFilter();
1694    setupDrawBlending(mode);
1695    setupDrawProgram();
1696    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1697    setupDrawColorUniforms();
1698    setupDrawShaderUniforms(ignoreTransform);
1699    setupDrawColorFilterUniforms();
1700    setupDrawSimpleMesh();
1701
1702    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1703}
1704
1705void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1706        Texture* texture, SkPaint* paint) {
1707    int alpha;
1708    SkXfermode::Mode mode;
1709    getAlphaAndMode(paint, &alpha, &mode);
1710
1711    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1712
1713    if (mSnapshot->transform->isPureTranslate()) {
1714        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1715        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1716
1717        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1718                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1719                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1720    } else {
1721        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1722                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1723                GL_TRIANGLE_STRIP, gMeshCount);
1724    }
1725}
1726
1727void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1728        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1729    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1730            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1731}
1732
1733void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1734        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1735        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1736        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1737
1738    setupDraw();
1739    setupDrawWithTexture();
1740    setupDrawColor(alpha, alpha, alpha, alpha);
1741    setupDrawColorFilter();
1742    setupDrawBlending(blend, mode, swapSrcDst);
1743    setupDrawProgram();
1744    if (!dirty) {
1745        setupDrawDirtyRegionsDisabled();
1746    }
1747    if (!ignoreScale) {
1748        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1749    } else {
1750        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1751    }
1752    setupDrawPureColorUniforms();
1753    setupDrawColorFilterUniforms();
1754    setupDrawTexture(texture);
1755    setupDrawMesh(vertices, texCoords, vbo);
1756
1757    glDrawArrays(drawMode, 0, elementsCount);
1758
1759    finishDrawTexture();
1760}
1761
1762void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1763        ProgramDescription& description, bool swapSrcDst) {
1764    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1765    if (blend) {
1766        if (mode < SkXfermode::kPlus_Mode) {
1767            if (!mCaches.blend) {
1768                glEnable(GL_BLEND);
1769            }
1770
1771            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1772            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1773
1774            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1775                glBlendFunc(sourceMode, destMode);
1776                mCaches.lastSrcMode = sourceMode;
1777                mCaches.lastDstMode = destMode;
1778            }
1779        } else {
1780            // These blend modes are not supported by OpenGL directly and have
1781            // to be implemented using shaders. Since the shader will perform
1782            // the blending, turn blending off here
1783            if (mCaches.extensions.hasFramebufferFetch()) {
1784                description.framebufferMode = mode;
1785                description.swapSrcDst = swapSrcDst;
1786            }
1787
1788            if (mCaches.blend) {
1789                glDisable(GL_BLEND);
1790            }
1791            blend = false;
1792        }
1793    } else if (mCaches.blend) {
1794        glDisable(GL_BLEND);
1795    }
1796    mCaches.blend = blend;
1797}
1798
1799bool OpenGLRenderer::useProgram(Program* program) {
1800    if (!program->isInUse()) {
1801        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1802        program->use();
1803        mCaches.currentProgram = program;
1804        return false;
1805    }
1806    return true;
1807}
1808
1809void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1810    TextureVertex* v = &mMeshVertices[0];
1811    TextureVertex::setUV(v++, u1, v1);
1812    TextureVertex::setUV(v++, u2, v1);
1813    TextureVertex::setUV(v++, u1, v2);
1814    TextureVertex::setUV(v++, u2, v2);
1815}
1816
1817void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1818    if (paint) {
1819        if (!mCaches.extensions.hasFramebufferFetch()) {
1820            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1821            if (!isMode) {
1822                // Assume SRC_OVER
1823                *mode = SkXfermode::kSrcOver_Mode;
1824            }
1825        } else {
1826            *mode = getXfermode(paint->getXfermode());
1827        }
1828
1829        // Skia draws using the color's alpha channel if < 255
1830        // Otherwise, it uses the paint's alpha
1831        int color = paint->getColor();
1832        *alpha = (color >> 24) & 0xFF;
1833        if (*alpha == 255) {
1834            *alpha = paint->getAlpha();
1835        }
1836    } else {
1837        *mode = SkXfermode::kSrcOver_Mode;
1838        *alpha = 255;
1839    }
1840}
1841
1842SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1843    if (mode == NULL) {
1844        return SkXfermode::kSrcOver_Mode;
1845    }
1846    return mode->fMode;
1847}
1848
1849void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1850    bool bound = false;
1851    if (wrapS != texture->wrapS) {
1852        glBindTexture(GL_TEXTURE_2D, texture->id);
1853        bound = true;
1854        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1855        texture->wrapS = wrapS;
1856    }
1857    if (wrapT != texture->wrapT) {
1858        if (!bound) {
1859            glBindTexture(GL_TEXTURE_2D, texture->id);
1860        }
1861        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1862        texture->wrapT = wrapT;
1863    }
1864}
1865
1866}; // namespace uirenderer
1867}; // namespace android
1868