OpenGLRenderer.cpp revision 70ca14e08ae197547ac412e8a1210e1ebdfb2eb1 
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    }
166#endif
167#if DEBUG_MEMORY_USAGE
168    mCaches.dumpMemoryUsage();
169#else
170    if (mCaches.getDebugLevel() & kDebugMemory) {
171        mCaches.dumpMemoryUsage();
172    }
173#endif
174}
175
176void OpenGLRenderer::acquireContext() {
177    if (mCaches.currentProgram) {
178        if (mCaches.currentProgram->isInUse()) {
179            mCaches.currentProgram->remove();
180            mCaches.currentProgram = NULL;
181        }
182    }
183    mCaches.unbindMeshBuffer();
184}
185
186void OpenGLRenderer::releaseContext() {
187    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
188
189    glEnable(GL_SCISSOR_TEST);
190    dirtyClip();
191
192    glDisable(GL_DITHER);
193
194    glBindFramebuffer(GL_FRAMEBUFFER, 0);
195    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
196
197    mCaches.blend = true;
198    glEnable(GL_BLEND);
199    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
200    glBlendEquation(GL_FUNC_ADD);
201}
202
203///////////////////////////////////////////////////////////////////////////////
204// State management
205///////////////////////////////////////////////////////////////////////////////
206
207int OpenGLRenderer::getSaveCount() const {
208    return mSaveCount;
209}
210
211int OpenGLRenderer::save(int flags) {
212    return saveSnapshot(flags);
213}
214
215void OpenGLRenderer::restore() {
216    if (mSaveCount > 1) {
217        restoreSnapshot();
218    }
219}
220
221void OpenGLRenderer::restoreToCount(int saveCount) {
222    if (saveCount < 1) saveCount = 1;
223
224    while (mSaveCount > saveCount) {
225        restoreSnapshot();
226    }
227}
228
229int OpenGLRenderer::saveSnapshot(int flags) {
230    mSnapshot = new Snapshot(mSnapshot, flags);
231    return mSaveCount++;
232}
233
234bool OpenGLRenderer::restoreSnapshot() {
235    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
236    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
237    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
238
239    sp<Snapshot> current = mSnapshot;
240    sp<Snapshot> previous = mSnapshot->previous;
241
242    if (restoreOrtho) {
243        Rect& r = previous->viewport;
244        glViewport(r.left, r.top, r.right, r.bottom);
245        mOrthoMatrix.load(current->orthoMatrix);
246    }
247
248    mSaveCount--;
249    mSnapshot = previous;
250
251    if (restoreClip) {
252        dirtyClip();
253    }
254
255    if (restoreLayer) {
256        composeLayer(current, previous);
257    }
258
259    return restoreClip;
260}
261
262///////////////////////////////////////////////////////////////////////////////
263// Layers
264///////////////////////////////////////////////////////////////////////////////
265
266int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
267        SkPaint* p, int flags) {
268    const GLuint previousFbo = mSnapshot->fbo;
269    const int count = saveSnapshot(flags);
270
271    if (!mSnapshot->isIgnored()) {
272        int alpha = 255;
273        SkXfermode::Mode mode;
274
275        if (p) {
276            alpha = p->getAlpha();
277            if (!mCaches.extensions.hasFramebufferFetch()) {
278                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
279                if (!isMode) {
280                    // Assume SRC_OVER
281                    mode = SkXfermode::kSrcOver_Mode;
282                }
283            } else {
284                mode = getXfermode(p->getXfermode());
285            }
286        } else {
287            mode = SkXfermode::kSrcOver_Mode;
288        }
289
290        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
291    }
292
293    return count;
294}
295
296int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
297        int alpha, int flags) {
298    if (alpha >= 255 - ALPHA_THRESHOLD) {
299        return saveLayer(left, top, right, bottom, NULL, flags);
300    } else {
301        SkPaint paint;
302        paint.setAlpha(alpha);
303        return saveLayer(left, top, right, bottom, &paint, flags);
304    }
305}
306
307/**
308 * Layers are viewed by Skia are slightly different than layers in image editing
309 * programs (for instance.) When a layer is created, previously created layers
310 * and the frame buffer still receive every drawing command. For instance, if a
311 * layer is created and a shape intersecting the bounds of the layers and the
312 * framebuffer is draw, the shape will be drawn on both (unless the layer was
313 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
314 *
315 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
316 * texture. Unfortunately, this is inefficient as it requires every primitive to
317 * be drawn n + 1 times, where n is the number of active layers. In practice this
318 * means, for every primitive:
319 *   - Switch active frame buffer
320 *   - Change viewport, clip and projection matrix
321 *   - Issue the drawing
322 *
323 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
324 * To avoid this, layers are implemented in a different way here, at least in the
325 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
326 * is set. When this flag is set we can redirect all drawing operations into a
327 * single FBO.
328 *
329 * This implementation relies on the frame buffer being at least RGBA 8888. When
330 * a layer is created, only a texture is created, not an FBO. The content of the
331 * frame buffer contained within the layer's bounds is copied into this texture
332 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
333 * buffer and drawing continues as normal. This technique therefore treats the
334 * frame buffer as a scratch buffer for the layers.
335 *
336 * To compose the layers back onto the frame buffer, each layer texture
337 * (containing the original frame buffer data) is drawn as a simple quad over
338 * the frame buffer. The trick is that the quad is set as the composition
339 * destination in the blending equation, and the frame buffer becomes the source
340 * of the composition.
341 *
342 * Drawing layers with an alpha value requires an extra step before composition.
343 * An empty quad is drawn over the layer's region in the frame buffer. This quad
344 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
345 * quad is used to multiply the colors in the frame buffer. This is achieved by
346 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
347 * GL_ZERO, GL_SRC_ALPHA.
348 *
349 * Because glCopyTexImage2D() can be slow, an alternative implementation might
350 * be use to draw a single clipped layer. The implementation described above
351 * is correct in every case.
352 *
353 * (1) The frame buffer is actually not cleared right away. To allow the GPU
354 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
355 *     buffer is left untouched until the first drawing operation. Only when
356 *     something actually gets drawn are the layers regions cleared.
357 */
358bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
359        float right, float bottom, int alpha, SkXfermode::Mode mode,
360        int flags, GLuint previousFbo) {
361    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
362    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
363
364    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
365
366    // Window coordinates of the layer
367    Rect bounds(left, top, right, bottom);
368    if (fboLayer) {
369        // Clear the previous layer regions before we change the viewport
370        clearLayerRegions();
371    } else {
372        mSnapshot->transform->mapRect(bounds);
373
374        // Layers only make sense if they are in the framebuffer's bounds
375        bounds.intersect(*snapshot->clipRect);
376
377        // We cannot work with sub-pixels in this case
378        bounds.snapToPixelBoundaries();
379
380        // When the layer is not an FBO, we may use glCopyTexImage so we
381        // need to make sure the layer does not extend outside the bounds
382        // of the framebuffer
383        bounds.intersect(snapshot->previous->viewport);
384    }
385
386    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
387            bounds.getHeight() > mCaches.maxTextureSize) {
388        snapshot->empty = fboLayer;
389    } else {
390        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
391    }
392
393    // Bail out if we won't draw in this snapshot
394    if (snapshot->invisible || snapshot->empty) {
395        return false;
396    }
397
398    glActiveTexture(gTextureUnits[0]);
399    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
400    if (!layer) {
401        return false;
402    }
403
404    layer->mode = mode;
405    layer->alpha = alpha;
406    layer->layer.set(bounds);
407    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
408            bounds.getWidth() / float(layer->width), 0.0f);
409
410    // Save the layer in the snapshot
411    snapshot->flags |= Snapshot::kFlagIsLayer;
412    snapshot->layer = layer;
413
414    if (fboLayer) {
415        return createFboLayer(layer, bounds, snapshot, previousFbo);
416    } else {
417        // Copy the framebuffer into the layer
418        glBindTexture(GL_TEXTURE_2D, layer->texture);
419
420        if (layer->empty) {
421            glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
422                    snapshot->height - bounds.bottom, layer->width, layer->height, 0);
423            layer->empty = false;
424        } else {
425            glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
426                    snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
427        }
428
429        // Enqueue the buffer coordinates to clear the corresponding region later
430        mLayers.push(new Rect(bounds));
431    }
432
433    return true;
434}
435
436bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
437        GLuint previousFbo) {
438    layer->fbo = mCaches.fboCache.get();
439
440#if RENDER_LAYERS_AS_REGIONS
441    snapshot->region = &snapshot->layer->region;
442    snapshot->flags |= Snapshot::kFlagFboTarget;
443#endif
444
445    Rect clip(bounds);
446    snapshot->transform->mapRect(clip);
447    clip.intersect(*snapshot->clipRect);
448    clip.snapToPixelBoundaries();
449    clip.intersect(snapshot->previous->viewport);
450
451    mat4 inverse;
452    inverse.loadInverse(*mSnapshot->transform);
453
454    inverse.mapRect(clip);
455    clip.snapToPixelBoundaries();
456    clip.intersect(bounds);
457    clip.translate(-bounds.left, -bounds.top);
458
459    snapshot->flags |= Snapshot::kFlagIsFboLayer;
460    snapshot->fbo = layer->fbo;
461    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
462    //snapshot->resetClip(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
463    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
464    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
465    snapshot->height = bounds.getHeight();
466    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
467    snapshot->orthoMatrix.load(mOrthoMatrix);
468
469    // Bind texture to FBO
470    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
471    glBindTexture(GL_TEXTURE_2D, layer->texture);
472
473    // Initialize the texture if needed
474    if (layer->empty) {
475        layer->empty = false;
476        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
477                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
478    }
479
480    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
481            layer->texture, 0);
482
483#if DEBUG_LAYERS_AS_REGIONS
484    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
485    if (status != GL_FRAMEBUFFER_COMPLETE) {
486        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
487
488        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
489        glDeleteTextures(1, &layer->texture);
490        mCaches.fboCache.put(layer->fbo);
491
492        delete layer;
493
494        return false;
495    }
496#endif
497
498    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
499    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
500            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
501    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
502    glClear(GL_COLOR_BUFFER_BIT);
503
504    dirtyClip();
505
506    // Change the ortho projection
507    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
508    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
509
510    return true;
511}
512
513/**
514 * Read the documentation of createLayer() before doing anything in this method.
515 */
516void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
517    if (!current->layer) {
518        LOGE("Attempting to compose a layer that does not exist");
519        return;
520    }
521
522    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
523
524    if (fboLayer) {
525        // Unbind current FBO and restore previous one
526        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
527    }
528
529    Layer* layer = current->layer;
530    const Rect& rect = layer->layer;
531
532    if (!fboLayer && layer->alpha < 255) {
533        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
534                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
535        // Required below, composeLayerRect() will divide by 255
536        layer->alpha = 255;
537    }
538
539    mCaches.unbindMeshBuffer();
540
541    glActiveTexture(gTextureUnits[0]);
542
543    // When the layer is stored in an FBO, we can save a bit of fillrate by
544    // drawing only the dirty region
545    if (fboLayer) {
546        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
547        composeLayerRegion(layer, rect);
548    } else {
549        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
550        composeLayerRect(layer, rect, true);
551    }
552
553    if (fboLayer) {
554        // Detach the texture from the FBO
555        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
556        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
557        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
558
559        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
560        mCaches.fboCache.put(current->fbo);
561    }
562
563    dirtyClip();
564
565    // Failing to add the layer to the cache should happen only if the layer is too large
566    if (!mCaches.layerCache.put(layer)) {
567        LAYER_LOGD("Deleting layer");
568        glDeleteTextures(1, &layer->texture);
569        delete layer;
570    }
571}
572
573void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
574    const Rect& texCoords = layer->texCoords;
575    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
576
577    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
578            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
579            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
580
581    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
582}
583
584void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
585#if RENDER_LAYERS_AS_REGIONS
586    if (layer->region.isRect()) {
587        composeLayerRect(layer, rect);
588        layer->region.clear();
589        return;
590    }
591
592    if (!layer->region.isEmpty()) {
593        size_t count;
594        const android::Rect* rects = layer->region.getArray(&count);
595
596        setupDraw();
597
598        ProgramDescription description;
599        description.hasTexture = true;
600
601        const float alpha = layer->alpha / 255.0f;
602        const bool setColor = description.setColor(alpha, alpha, alpha, alpha);
603        chooseBlending(layer->blend || layer->alpha < 255, layer->mode, description, false);
604
605        useProgram(mCaches.programCache.get(description));
606
607        // Texture
608        bindTexture(layer->texture);
609        glUniform1i(mCaches.currentProgram->getUniform("sampler"), 0);
610
611        // Always premultiplied
612        if (setColor) {
613            mCaches.currentProgram->setColor(alpha, alpha, alpha, alpha);
614        }
615
616        // Mesh
617        int texCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
618        glEnableVertexAttribArray(texCoordsSlot);
619
620        mModelView.loadIdentity();
621        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
622
623        const float texX = 1.0f / float(layer->width);
624        const float texY = 1.0f / float(layer->height);
625
626        TextureVertex* mesh = mCaches.getRegionMesh();
627        GLsizei numQuads = 0;
628
629        glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
630                gMeshStride, &mesh[0].position[0]);
631        glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE,
632                gMeshStride, &mesh[0].texture[0]);
633
634        for (size_t i = 0; i < count; i++) {
635            const android::Rect* r = &rects[i];
636
637            const float u1 = r->left * texX;
638            const float v1 = (rect.getHeight() - r->top) * texY;
639            const float u2 = r->right * texX;
640            const float v2 = (rect.getHeight() - r->bottom) * texY;
641
642            // TODO: Reject quads outside of the clip
643            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
644            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
645            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
646            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
647
648            numQuads++;
649
650            if (numQuads >= REGION_MESH_QUAD_COUNT) {
651                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
652                numQuads = 0;
653                mesh = mCaches.getRegionMesh();
654            }
655        }
656
657        if (numQuads > 0) {
658            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
659        }
660
661        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
662        glDisableVertexAttribArray(texCoordsSlot);
663
664#if DEBUG_LAYERS_AS_REGIONS
665        uint32_t colors[] = {
666                0x7fff0000, 0x7f00ff00,
667                0x7f0000ff, 0x7fff00ff,
668        };
669
670        int offset = 0;
671        int32_t top = rects[0].top;
672        int i = 0;
673
674        for (size_t i = 0; i < count; i++) {
675            if (top != rects[i].top) {
676                offset ^= 0x2;
677                top = rects[i].top;
678            }
679
680            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
681            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
682                    SkXfermode::kSrcOver_Mode);
683        }
684#endif
685
686        layer->region.clear();
687    }
688#else
689    composeLayerRect(layer, rect);
690#endif
691}
692
693void OpenGLRenderer::dirtyLayer(const float left, const float top,
694        const float right, const float bottom, const mat4 transform) {
695#if RENDER_LAYERS_AS_REGIONS
696    if ((mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region) {
697        Rect bounds(left, top, right, bottom);
698        transform.mapRect(bounds);
699        bounds.intersect(*mSnapshot->clipRect);
700        bounds.snapToPixelBoundaries();
701
702        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
703        if (!dirty.isEmpty()) {
704            mSnapshot->region->orSelf(dirty);
705        }
706    }
707#endif
708}
709
710void OpenGLRenderer::dirtyLayer(const float left, const float top,
711        const float right, const float bottom) {
712#if RENDER_LAYERS_AS_REGIONS
713    if ((mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region) {
714        Rect bounds(left, top, right, bottom);
715        bounds.intersect(*mSnapshot->clipRect);
716        bounds.snapToPixelBoundaries();
717
718        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
719        if (!dirty.isEmpty()) {
720            mSnapshot->region->orSelf(dirty);
721        }
722    }
723#endif
724}
725
726void OpenGLRenderer::clearLayerRegions() {
727    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
728
729    Rect clipRect(*mSnapshot->clipRect);
730    clipRect.snapToPixelBoundaries();
731
732    for (uint32_t i = 0; i < mLayers.size(); i++) {
733        Rect* bounds = mLayers.itemAt(i);
734        if (clipRect.intersects(*bounds)) {
735            // Clear the framebuffer where the layer will draw
736            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
737                    bounds->getWidth(), bounds->getHeight());
738            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
739            glClear(GL_COLOR_BUFFER_BIT);
740
741            // Restore the clip
742            dirtyClip();
743        }
744
745        delete bounds;
746    }
747
748    mLayers.clear();
749}
750
751///////////////////////////////////////////////////////////////////////////////
752// Transforms
753///////////////////////////////////////////////////////////////////////////////
754
755void OpenGLRenderer::translate(float dx, float dy) {
756    mSnapshot->transform->translate(dx, dy, 0.0f);
757}
758
759void OpenGLRenderer::rotate(float degrees) {
760    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
761}
762
763void OpenGLRenderer::scale(float sx, float sy) {
764    mSnapshot->transform->scale(sx, sy, 1.0f);
765}
766
767void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
768    mSnapshot->transform->load(*matrix);
769}
770
771const float* OpenGLRenderer::getMatrix() const {
772    if (mSnapshot->fbo != 0) {
773        return &mSnapshot->transform->data[0];
774    }
775    return &mIdentity.data[0];
776}
777
778void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
779    mSnapshot->transform->copyTo(*matrix);
780}
781
782void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
783    SkMatrix transform;
784    mSnapshot->transform->copyTo(transform);
785    transform.preConcat(*matrix);
786    mSnapshot->transform->load(transform);
787}
788
789///////////////////////////////////////////////////////////////////////////////
790// Clipping
791///////////////////////////////////////////////////////////////////////////////
792
793void OpenGLRenderer::setScissorFromClip() {
794    Rect clip(*mSnapshot->clipRect);
795    clip.snapToPixelBoundaries();
796    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
797    mDirtyClip = false;
798}
799
800const Rect& OpenGLRenderer::getClipBounds() {
801    return mSnapshot->getLocalClip();
802}
803
804bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
805    if (mSnapshot->isIgnored()) {
806        return true;
807    }
808
809    Rect r(left, top, right, bottom);
810    mSnapshot->transform->mapRect(r);
811    r.snapToPixelBoundaries();
812
813    Rect clipRect(*mSnapshot->clipRect);
814    clipRect.snapToPixelBoundaries();
815
816    return !clipRect.intersects(r);
817}
818
819bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
820    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
821    if (clipped) {
822        dirtyClip();
823    }
824    return !mSnapshot->clipRect->isEmpty();
825}
826
827///////////////////////////////////////////////////////////////////////////////
828// Drawing commands
829///////////////////////////////////////////////////////////////////////////////
830
831void OpenGLRenderer::setupDraw() {
832    clearLayerRegions();
833    if (mDirtyClip) {
834        setScissorFromClip();
835    }
836    mDescription.reset();
837    mSetShaderColor = false;
838    mColorSet = false;
839    mColorA = mColorR = mColorG = mColorB = 0.0f;
840    mTextureUnit = 0;
841    mTrackDirtyRegions = true;
842}
843
844void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
845    mDescription.hasTexture = true;
846    mDescription.hasAlpha8Texture = isAlpha8;
847}
848
849void OpenGLRenderer::setupDrawColor(int color) {
850    mColorA = ((color >> 24) & 0xFF) / 255.0f;
851    const float a = mColorA / 255.0f;
852    mColorR = mColorA * ((color >> 16) & 0xFF);
853    mColorG = mColorA * ((color >>  8) & 0xFF);
854    mColorB = mColorA * ((color      ) & 0xFF);
855    mColorSet = true;
856    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
857}
858
859void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
860    mColorA = a;
861    mColorR = r;
862    mColorG = g;
863    mColorB = b;
864    mColorSet = true;
865    mSetShaderColor = mDescription.setColor(r, g, b, a);
866}
867
868void OpenGLRenderer::setupDrawShader() {
869    if (mShader) {
870        mShader->describe(mDescription, mCaches.extensions);
871    }
872}
873
874void OpenGLRenderer::setupDrawColorFilter() {
875    if (mColorFilter) {
876        mColorFilter->describe(mDescription, mCaches.extensions);
877    }
878}
879
880void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
881    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
882            mDescription, swapSrcDst);
883}
884
885void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
886    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
887            mDescription, swapSrcDst);
888}
889
890void OpenGLRenderer::setupDrawProgram() {
891    useProgram(mCaches.programCache.get(mDescription));
892}
893
894void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
895    mTrackDirtyRegions = false;
896}
897
898void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
899        bool ignoreTransform) {
900    mModelView.loadTranslate(left, top, 0.0f);
901    if (!ignoreTransform) {
902        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
903        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
904    } else {
905        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
906        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
907    }
908}
909
910void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
911        bool ignoreTransform, bool ignoreModelView) {
912    if (!ignoreModelView) {
913        mModelView.loadTranslate(left, top, 0.0f);
914        mModelView.scale(right - left, bottom - top, 1.0f);
915        if (!ignoreTransform) {
916            mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
917            if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
918        } else {
919            mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
920            if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
921        }
922    } else {
923        mModelView.loadIdentity();
924    }
925}
926
927void OpenGLRenderer::setupDrawColorUniforms() {
928    if (mColorSet && mSetShaderColor) {
929        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
930    }
931}
932
933void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
934    if (mShader) {
935        if (ignoreTransform) {
936            mModelView.loadInverse(*mSnapshot->transform);
937        }
938        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
939    }
940}
941
942void OpenGLRenderer::setupDrawColorFilterUniforms() {
943    if (mColorFilter) {
944        mColorFilter->setupProgram(mCaches.currentProgram);
945    }
946}
947
948void OpenGLRenderer::setupDrawSimpleMesh() {
949    mCaches.bindMeshBuffer();
950    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
951            gMeshStride, 0);
952}
953
954void OpenGLRenderer::setupDrawTexture(GLuint texture) {
955    bindTexture(texture);
956    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
957
958    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
959    glEnableVertexAttribArray(mTexCoordsSlot);
960}
961
962void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
963    if (!vertices) {
964        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
965    } else {
966        mCaches.unbindMeshBuffer();
967    }
968    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
969            gMeshStride, vertices);
970    glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
971}
972
973void OpenGLRenderer::finishDrawTexture() {
974    glDisableVertexAttribArray(mTexCoordsSlot);
975}
976
977///////////////////////////////////////////////////////////////////////////////
978// Drawing
979///////////////////////////////////////////////////////////////////////////////
980
981void OpenGLRenderer::drawDisplayList(DisplayList* displayList) {
982    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
983    // will be performed by the display list itself
984    if (displayList) {
985        displayList->replay(*this);
986    }
987}
988
989void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
990    const float right = left + bitmap->width();
991    const float bottom = top + bitmap->height();
992
993    if (quickReject(left, top, right, bottom)) {
994        return;
995    }
996
997    glActiveTexture(GL_TEXTURE0);
998    Texture* texture = mCaches.textureCache.get(bitmap);
999    if (!texture) return;
1000    const AutoTexture autoCleanup(texture);
1001
1002    drawTextureRect(left, top, right, bottom, texture, paint);
1003}
1004
1005void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1006    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1007    const mat4 transform(*matrix);
1008    transform.mapRect(r);
1009
1010    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1011        return;
1012    }
1013
1014    glActiveTexture(GL_TEXTURE0);
1015    Texture* texture = mCaches.textureCache.get(bitmap);
1016    if (!texture) return;
1017    const AutoTexture autoCleanup(texture);
1018
1019    // This could be done in a cheaper way, all we need is pass the matrix
1020    // to the vertex shader. The save/restore is a bit overkill.
1021    save(SkCanvas::kMatrix_SaveFlag);
1022    concatMatrix(matrix);
1023    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1024    restore();
1025}
1026
1027void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1028         float srcLeft, float srcTop, float srcRight, float srcBottom,
1029         float dstLeft, float dstTop, float dstRight, float dstBottom,
1030         SkPaint* paint) {
1031    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1032        return;
1033    }
1034
1035    glActiveTexture(gTextureUnits[0]);
1036    Texture* texture = mCaches.textureCache.get(bitmap);
1037    if (!texture) return;
1038    const AutoTexture autoCleanup(texture);
1039    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1040
1041    const float width = texture->width;
1042    const float height = texture->height;
1043
1044    const float u1 = srcLeft / width;
1045    const float v1 = srcTop / height;
1046    const float u2 = srcRight / width;
1047    const float v2 = srcBottom / height;
1048
1049    mCaches.unbindMeshBuffer();
1050    resetDrawTextureTexCoords(u1, v1, u2, v2);
1051
1052    int alpha;
1053    SkXfermode::Mode mode;
1054    getAlphaAndMode(paint, &alpha, &mode);
1055
1056    if (mSnapshot->transform->isPureTranslate()) {
1057        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1058        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1059
1060        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1061                texture->id, alpha / 255.0f, mode, texture->blend,
1062                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1063                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1064    } else {
1065        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1066                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1067                GL_TRIANGLE_STRIP, gMeshCount);
1068    }
1069
1070    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1071}
1072
1073void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1074        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1075        float left, float top, float right, float bottom, SkPaint* paint) {
1076    if (quickReject(left, top, right, bottom)) {
1077        return;
1078    }
1079
1080    glActiveTexture(gTextureUnits[0]);
1081    Texture* texture = mCaches.textureCache.get(bitmap);
1082    if (!texture) return;
1083    const AutoTexture autoCleanup(texture);
1084    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1085
1086    int alpha;
1087    SkXfermode::Mode mode;
1088    getAlphaAndMode(paint, &alpha, &mode);
1089
1090    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1091            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1092
1093    if (mesh && mesh->verticesCount > 0) {
1094        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1095#if RENDER_LAYERS_AS_REGIONS
1096        // Mark the current layer dirty where we are going to draw the patch
1097        if ((mSnapshot->flags & Snapshot::kFlagFboTarget) &&
1098                mSnapshot->region && mesh->hasEmptyQuads) {
1099            const size_t count = mesh->quads.size();
1100            for (size_t i = 0; i < count; i++) {
1101                const Rect& bounds = mesh->quads.itemAt(i);
1102                if (pureTranslate) {
1103                    const float x = (int) floorf(bounds.left + 0.5f);
1104                    const float y = (int) floorf(bounds.top + 0.5f);
1105                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1106                            *mSnapshot->transform);
1107                } else {
1108                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1109                            *mSnapshot->transform);
1110                }
1111            }
1112        }
1113#endif
1114
1115        if (pureTranslate) {
1116            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1117            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1118
1119            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1120                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1121                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1122                    true, !mesh->hasEmptyQuads);
1123        } else {
1124            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1125                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1126                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1127                    true, !mesh->hasEmptyQuads);
1128        }
1129    }
1130}
1131
1132void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1133    // TODO: Should do quickReject for each line
1134    if (mSnapshot->isIgnored()) return;
1135
1136    const bool isAA = paint->isAntiAlias();
1137    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1138    // A stroke width of 0 has a special meaningin Skia:
1139    // it draws an unscaled 1px wide line
1140    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1141
1142    setupDraw();
1143
1144    int alpha;
1145    SkXfermode::Mode mode;
1146    getAlphaAndMode(paint, &alpha, &mode);
1147
1148    uint32_t color = paint->getColor();
1149    const GLfloat a = alpha / 255.0f;
1150    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
1151    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
1152    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
1153
1154    // Used only with AA lines
1155    GLuint textureUnit = 0;
1156
1157    // Describe the required shaders
1158    ProgramDescription description;
1159    const bool setColor = description.setColor(r, g, b, a);
1160
1161    if (mShader) {
1162        mShader->describe(description, mCaches.extensions);
1163    }
1164    if (mColorFilter) {
1165        mColorFilter->describe(description, mCaches.extensions);
1166    }
1167
1168    // Setup the blending mode
1169    chooseBlending(a < 1.0f || (mShader && mShader->blend()), mode, description);
1170
1171    // We're not drawing with VBOs here
1172    mCaches.unbindMeshBuffer();
1173
1174    int verticesCount = count >> 2;
1175    if (!isHairLine) {
1176        // TODO: AA needs more vertices
1177        verticesCount *= 6;
1178    } else {
1179        // TODO: AA will be different
1180        verticesCount *= 2;
1181    }
1182
1183    TextureVertex lines[verticesCount];
1184    TextureVertex* vertex = &lines[0];
1185
1186    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1187            gMeshStride, vertex);
1188
1189    // Build and use the appropriate shader
1190    useProgram(mCaches.programCache.get(description));
1191    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
1192
1193    if (!mShader || (mShader && setColor)) {
1194        mCaches.currentProgram->setColor(r, g, b, a);
1195    }
1196
1197    if (mShader) {
1198        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &textureUnit);
1199    }
1200    if (mColorFilter) {
1201        mColorFilter->setupProgram(mCaches.currentProgram);
1202    }
1203
1204    if (!isHairLine) {
1205        // TODO: Handle the AA case
1206        for (int i = 0; i < count; i += 4) {
1207            // a = start point, b = end point
1208            vec2 a(points[i], points[i + 1]);
1209            vec2 b(points[i + 2], points[i + 3]);
1210
1211            // Bias to snap to the same pixels as Skia
1212            a += 0.375;
1213            b += 0.375;
1214
1215            // Find the normal to the line
1216            vec2 n = (b - a).copyNormalized() * strokeWidth;
1217            float x = n.x;
1218            n.x = -n.y;
1219            n.y = x;
1220
1221            // Four corners of the rectangle defining a thick line
1222            vec2 p1 = a - n;
1223            vec2 p2 = a + n;
1224            vec2 p3 = b + n;
1225            vec2 p4 = b - n;
1226
1227            // Draw the line as 2 triangles, could be optimized
1228            // by using only 4 vertices and the correct indices
1229            // Also we should probably used non textured vertices
1230            // when line AA is disabled to save on bandwidth
1231            TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1232            TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1233            TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1234            TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1235            TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1236            TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1237
1238            // TODO: Mark the dirty regions when RENDER_LAYERS_AS_REGIONS is set
1239        }
1240
1241        // GL_LINE does not give the result we want to match Skia
1242        glDrawArrays(GL_TRIANGLES, 0, verticesCount);
1243    } else {
1244        // TODO: Handle the AA case
1245        for (int i = 0; i < count; i += 4) {
1246            TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1247            TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1248        }
1249        glLineWidth(1.0f);
1250        glDrawArrays(GL_LINES, 0, verticesCount);
1251    }
1252}
1253
1254void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1255    // No need to check against the clip, we fill the clip region
1256    if (mSnapshot->isIgnored()) return;
1257
1258    Rect& clip(*mSnapshot->clipRect);
1259    clip.snapToPixelBoundaries();
1260
1261    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1262}
1263
1264void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1265    if (quickReject(left, top, right, bottom)) {
1266        return;
1267    }
1268
1269    SkXfermode::Mode mode;
1270    if (!mCaches.extensions.hasFramebufferFetch()) {
1271        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1272        if (!isMode) {
1273            // Assume SRC_OVER
1274            mode = SkXfermode::kSrcOver_Mode;
1275        }
1276    } else {
1277        mode = getXfermode(p->getXfermode());
1278    }
1279
1280    // Skia draws using the color's alpha channel if < 255
1281    // Otherwise, it uses the paint's alpha
1282    int color = p->getColor();
1283    if (((color >> 24) & 0xff) == 255) {
1284        color |= p->getAlpha() << 24;
1285    }
1286
1287    drawColorRect(left, top, right, bottom, color, mode);
1288}
1289
1290void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1291        float x, float y, SkPaint* paint) {
1292    if (text == NULL || count == 0 || (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
1293        return;
1294    }
1295    if (mSnapshot->isIgnored()) return;
1296
1297    paint->setAntiAlias(true);
1298
1299    float length = -1.0f;
1300    switch (paint->getTextAlign()) {
1301        case SkPaint::kCenter_Align:
1302            length = paint->measureText(text, bytesCount);
1303            x -= length / 2.0f;
1304            break;
1305        case SkPaint::kRight_Align:
1306            length = paint->measureText(text, bytesCount);
1307            x -= length;
1308            break;
1309        default:
1310            break;
1311    }
1312
1313    // TODO: Handle paint->getTextScaleX()
1314    const float oldX = x;
1315    const float oldY = y;
1316    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1317    if (pureTranslate) {
1318        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1319        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1320    }
1321
1322    int alpha;
1323    SkXfermode::Mode mode;
1324    getAlphaAndMode(paint, &alpha, &mode);
1325
1326    uint32_t color = paint->getColor();
1327    const GLfloat a = alpha / 255.0f;
1328    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
1329    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
1330    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
1331
1332    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1333    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1334            paint->getTextSize());
1335
1336    setupDraw();
1337
1338    if (mHasShadow) {
1339        glActiveTexture(gTextureUnits[0]);
1340        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1341        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1342                count, mShadowRadius);
1343        const AutoTexture autoCleanup(shadow);
1344
1345        setupShadow(shadow, x, y, mode, a, pureTranslate);
1346
1347        // Draw the mesh
1348        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1349        glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1350    }
1351
1352    GLuint textureUnit = 0;
1353    glActiveTexture(gTextureUnits[textureUnit]);
1354
1355    // Pick the appropriate texture filtering
1356    bool linearFilter = mSnapshot->transform->changesBounds();
1357    if (pureTranslate && !linearFilter) {
1358        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1359    }
1360
1361    // Dimensions are set to (0,0), the layer (if any) won't be dirtied
1362    setupTextureAlpha8(fontRenderer.getTexture(linearFilter), 0, 0, textureUnit,
1363            x, y, r, g, b, a, mode, false, true, NULL, NULL, 0, pureTranslate);
1364
1365    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1366    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1367
1368#if RENDER_LAYERS_AS_REGIONS
1369    bool hasLayer = (mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region;
1370#else
1371    bool hasLayer = false;
1372#endif
1373
1374    mCaches.unbindMeshBuffer();
1375    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1376            hasLayer ? &bounds : NULL)) {
1377#if RENDER_LAYERS_AS_REGIONS
1378        if (hasLayer) {
1379            if (!pureTranslate) {
1380                mSnapshot->transform->mapRect(bounds);
1381            }
1382            bounds.intersect(*mSnapshot->clipRect);
1383            bounds.snapToPixelBoundaries();
1384
1385            android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1386            mSnapshot->region->orSelf(dirty);
1387        }
1388#endif
1389    }
1390
1391    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1392    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1393
1394    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1395}
1396
1397void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1398    if (mSnapshot->isIgnored()) return;
1399
1400    GLuint textureUnit = 0;
1401    glActiveTexture(gTextureUnits[textureUnit]);
1402
1403    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1404    if (!texture) return;
1405    const AutoTexture autoCleanup(texture);
1406
1407    const float x = texture->left - texture->offset;
1408    const float y = texture->top - texture->offset;
1409
1410    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1411        return;
1412    }
1413
1414    int alpha;
1415    SkXfermode::Mode mode;
1416    getAlphaAndMode(paint, &alpha, &mode);
1417
1418    uint32_t color = paint->getColor();
1419    const GLfloat a = alpha / 255.0f;
1420    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
1421    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
1422    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
1423
1424    setupTextureAlpha8(texture, textureUnit, x, y, r, g, b, a, mode, true, true);
1425
1426    setupDraw();
1427
1428    // Draw the mesh
1429    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1430    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1431}
1432
1433///////////////////////////////////////////////////////////////////////////////
1434// Shaders
1435///////////////////////////////////////////////////////////////////////////////
1436
1437void OpenGLRenderer::resetShader() {
1438    mShader = NULL;
1439}
1440
1441void OpenGLRenderer::setupShader(SkiaShader* shader) {
1442    mShader = shader;
1443    if (mShader) {
1444        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1445    }
1446}
1447
1448///////////////////////////////////////////////////////////////////////////////
1449// Color filters
1450///////////////////////////////////////////////////////////////////////////////
1451
1452void OpenGLRenderer::resetColorFilter() {
1453    mColorFilter = NULL;
1454}
1455
1456void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1457    mColorFilter = filter;
1458}
1459
1460///////////////////////////////////////////////////////////////////////////////
1461// Drop shadow
1462///////////////////////////////////////////////////////////////////////////////
1463
1464void OpenGLRenderer::resetShadow() {
1465    mHasShadow = false;
1466}
1467
1468void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1469    mHasShadow = true;
1470    mShadowRadius = radius;
1471    mShadowDx = dx;
1472    mShadowDy = dy;
1473    mShadowColor = color;
1474}
1475
1476///////////////////////////////////////////////////////////////////////////////
1477// Drawing implementation
1478///////////////////////////////////////////////////////////////////////////////
1479
1480void OpenGLRenderer::setupShadow(const ShadowTexture* texture, float x, float y,
1481        SkXfermode::Mode mode, float alpha, bool ignoreTransforms) {
1482    const float sx = x - texture->left + mShadowDx;
1483    const float sy = y - texture->top + mShadowDy;
1484
1485    const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1486    const GLfloat a = shadowAlpha < 255 ? shadowAlpha / 255.0f : alpha;
1487    const GLfloat r = a * ((mShadowColor >> 16) & 0xFF) / 255.0f;
1488    const GLfloat g = a * ((mShadowColor >>  8) & 0xFF) / 255.0f;
1489    const GLfloat b = a * ((mShadowColor      ) & 0xFF) / 255.0f;
1490
1491    GLuint textureUnit = 0;
1492    setupTextureAlpha8(texture->id, texture->width, texture->height, textureUnit,
1493            sx, sy, r, g, b, a, mode, true, false,
1494            (GLvoid*) 0, (GLvoid*) gMeshTextureOffset, 0, ignoreTransforms);
1495}
1496
1497void OpenGLRenderer::setupTextureAlpha8(const Texture* texture, GLuint& textureUnit,
1498        float x, float y, float r, float g, float b, float a, SkXfermode::Mode mode,
1499        bool transforms, bool applyFilters) {
1500    setupTextureAlpha8(texture->id, texture->width, texture->height, textureUnit,
1501            x, y, r, g, b, a, mode, transforms, applyFilters,
1502            (GLvoid*) 0, (GLvoid*) gMeshTextureOffset);
1503}
1504
1505void OpenGLRenderer::setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
1506        GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
1507        SkXfermode::Mode mode, bool transforms, bool applyFilters) {
1508    setupTextureAlpha8(texture, width, height, textureUnit, x, y, r, g, b, a, mode,
1509            transforms, applyFilters, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset);
1510}
1511
1512void OpenGLRenderer::setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
1513        GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
1514        SkXfermode::Mode mode, bool transforms, bool applyFilters,
1515        GLvoid* vertices, GLvoid* texCoords, GLuint vbo, bool ignoreTransform) {
1516     // Describe the required shaders
1517     ProgramDescription description;
1518     description.hasTexture = true;
1519     description.hasAlpha8Texture = true;
1520     const bool setColor = description.setAlpha8Color(r, g, b, a);
1521
1522     if (applyFilters) {
1523         if (mShader) {
1524             mShader->describe(description, mCaches.extensions);
1525         }
1526         if (mColorFilter) {
1527             mColorFilter->describe(description, mCaches.extensions);
1528         }
1529     }
1530
1531     // Setup the blending mode
1532     chooseBlending(true, mode, description);
1533
1534     // Build and use the appropriate shader
1535     useProgram(mCaches.programCache.get(description));
1536
1537     bindTexture(texture);
1538     glUniform1i(mCaches.currentProgram->getUniform("sampler"), textureUnit);
1539
1540     int texCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1541     glEnableVertexAttribArray(texCoordsSlot);
1542
1543     if (texCoords) {
1544         // Setup attributes
1545         if (!vertices) {
1546             mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1547         } else {
1548             mCaches.unbindMeshBuffer();
1549         }
1550         glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1551                 gMeshStride, vertices);
1552         glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1553     }
1554
1555     // Setup uniforms
1556     if (transforms) {
1557         mModelView.loadTranslate(x, y, 0.0f);
1558         mModelView.scale(width, height, 1.0f);
1559     } else {
1560         mModelView.loadIdentity();
1561     }
1562
1563     mat4 t;
1564     if (!ignoreTransform) {
1565         t.load(*mSnapshot->transform);
1566     }
1567
1568     mCaches.currentProgram->set(mOrthoMatrix, mModelView, t);
1569     if (width > 0 && height > 0) {
1570         dirtyLayer(x, y, x + width, y + height, t);
1571     }
1572
1573     if (setColor) {
1574         mCaches.currentProgram->setColor(r, g, b, a);
1575     }
1576
1577     textureUnit++;
1578     if (applyFilters) {
1579         // Setup attributes and uniforms required by the shaders
1580         if (mShader) {
1581             if (ignoreTransform) {
1582                 mModelView.loadInverse(*mSnapshot->transform);
1583             }
1584             mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &textureUnit);
1585         }
1586         if (mColorFilter) {
1587             mColorFilter->setupProgram(mCaches.currentProgram);
1588         }
1589     }
1590}
1591
1592// Same values used by Skia
1593#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1594#define kStdUnderline_Offset    (1.0f / 9.0f)
1595#define kStdUnderline_Thickness (1.0f / 18.0f)
1596
1597void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1598        float x, float y, SkPaint* paint) {
1599    // Handle underline and strike-through
1600    uint32_t flags = paint->getFlags();
1601    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1602        float underlineWidth = length;
1603        // If length is > 0.0f, we already measured the text for the text alignment
1604        if (length <= 0.0f) {
1605            underlineWidth = paint->measureText(text, bytesCount);
1606        }
1607
1608        float offsetX = 0;
1609        switch (paint->getTextAlign()) {
1610            case SkPaint::kCenter_Align:
1611                offsetX = underlineWidth * 0.5f;
1612                break;
1613            case SkPaint::kRight_Align:
1614                offsetX = underlineWidth;
1615                break;
1616            default:
1617                break;
1618        }
1619
1620        if (underlineWidth > 0.0f) {
1621            const float textSize = paint->getTextSize();
1622            const float strokeWidth = textSize * kStdUnderline_Thickness;
1623
1624            const float left = x - offsetX;
1625            float top = 0.0f;
1626
1627            const int pointsCount = 4 * (flags & SkPaint::kStrikeThruText_Flag ? 2 : 1);
1628            float points[pointsCount];
1629            int currentPoint = 0;
1630
1631            if (flags & SkPaint::kUnderlineText_Flag) {
1632                top = y + textSize * kStdUnderline_Offset;
1633                points[currentPoint++] = left;
1634                points[currentPoint++] = top;
1635                points[currentPoint++] = left + underlineWidth;
1636                points[currentPoint++] = top;
1637            }
1638
1639            if (flags & SkPaint::kStrikeThruText_Flag) {
1640                top = y + textSize * kStdStrikeThru_Offset;
1641                points[currentPoint++] = left;
1642                points[currentPoint++] = top;
1643                points[currentPoint++] = left + underlineWidth;
1644                points[currentPoint++] = top;
1645            }
1646
1647            SkPaint linesPaint(*paint);
1648            linesPaint.setStrokeWidth(strokeWidth);
1649
1650            drawLines(&points[0], pointsCount, &linesPaint);
1651        }
1652    }
1653}
1654
1655void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1656        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1657    // If a shader is set, preserve only the alpha
1658    if (mShader) {
1659        color |= 0x00ffffff;
1660    }
1661
1662    setupDraw();
1663    setupDrawColor(color);
1664    setupDrawShader();
1665    setupDrawColorFilter();
1666    setupDrawBlending(mode);
1667    setupDrawProgram();
1668    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1669    setupDrawColorUniforms();
1670    setupDrawShaderUniforms(ignoreTransform);
1671    setupDrawColorFilterUniforms();
1672    setupDrawSimpleMesh();
1673
1674    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1675}
1676
1677void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1678        Texture* texture, SkPaint* paint) {
1679    int alpha;
1680    SkXfermode::Mode mode;
1681    getAlphaAndMode(paint, &alpha, &mode);
1682
1683    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1684
1685    if (mSnapshot->transform->isPureTranslate()) {
1686        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1687        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1688
1689        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1690                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1691                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1692    } else {
1693        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1694                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1695                GL_TRIANGLE_STRIP, gMeshCount);
1696    }
1697}
1698
1699void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1700        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1701    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1702            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1703}
1704
1705void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1706        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1707        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1708        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1709
1710    setupDraw();
1711    setupDrawWithTexture();
1712    setupDrawColor(alpha, alpha, alpha, alpha);
1713    setupDrawColorFilter();
1714    setupDrawBlending(blend, mode, swapSrcDst);
1715    setupDrawProgram();
1716    if (!dirty) {
1717        setupDrawDirtyRegionsDisabled();
1718    }
1719    if (!ignoreScale) {
1720        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1721    } else {
1722        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1723    }
1724    setupDrawColorUniforms();
1725    setupDrawColorFilterUniforms();
1726    setupDrawTexture(texture);
1727    setupDrawMesh(vertices, texCoords, vbo);
1728
1729    glDrawArrays(drawMode, 0, elementsCount);
1730
1731    finishDrawTexture();
1732}
1733
1734void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1735        ProgramDescription& description, bool swapSrcDst) {
1736    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1737    if (blend) {
1738        if (mode < SkXfermode::kPlus_Mode) {
1739            if (!mCaches.blend) {
1740                glEnable(GL_BLEND);
1741            }
1742
1743            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1744            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1745
1746            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1747                glBlendFunc(sourceMode, destMode);
1748                mCaches.lastSrcMode = sourceMode;
1749                mCaches.lastDstMode = destMode;
1750            }
1751        } else {
1752            // These blend modes are not supported by OpenGL directly and have
1753            // to be implemented using shaders. Since the shader will perform
1754            // the blending, turn blending off here
1755            if (mCaches.extensions.hasFramebufferFetch()) {
1756                description.framebufferMode = mode;
1757                description.swapSrcDst = swapSrcDst;
1758            }
1759
1760            if (mCaches.blend) {
1761                glDisable(GL_BLEND);
1762            }
1763            blend = false;
1764        }
1765    } else if (mCaches.blend) {
1766        glDisable(GL_BLEND);
1767    }
1768    mCaches.blend = blend;
1769}
1770
1771bool OpenGLRenderer::useProgram(Program* program) {
1772    if (!program->isInUse()) {
1773        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1774        program->use();
1775        mCaches.currentProgram = program;
1776        return false;
1777    }
1778    return true;
1779}
1780
1781void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1782    TextureVertex* v = &mMeshVertices[0];
1783    TextureVertex::setUV(v++, u1, v1);
1784    TextureVertex::setUV(v++, u2, v1);
1785    TextureVertex::setUV(v++, u1, v2);
1786    TextureVertex::setUV(v++, u2, v2);
1787}
1788
1789void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1790    if (paint) {
1791        if (!mCaches.extensions.hasFramebufferFetch()) {
1792            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1793            if (!isMode) {
1794                // Assume SRC_OVER
1795                *mode = SkXfermode::kSrcOver_Mode;
1796            }
1797        } else {
1798            *mode = getXfermode(paint->getXfermode());
1799        }
1800
1801        // Skia draws using the color's alpha channel if < 255
1802        // Otherwise, it uses the paint's alpha
1803        int color = paint->getColor();
1804        *alpha = (color >> 24) & 0xFF;
1805        if (*alpha == 255) {
1806            *alpha = paint->getAlpha();
1807        }
1808    } else {
1809        *mode = SkXfermode::kSrcOver_Mode;
1810        *alpha = 255;
1811    }
1812}
1813
1814SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1815    if (mode == NULL) {
1816        return SkXfermode::kSrcOver_Mode;
1817    }
1818    return mode->fMode;
1819}
1820
1821void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1822    bool bound = false;
1823    if (wrapS != texture->wrapS) {
1824        glBindTexture(GL_TEXTURE_2D, texture->id);
1825        bound = true;
1826        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1827        texture->wrapS = wrapS;
1828    }
1829    if (wrapT != texture->wrapT) {
1830        if (!bound) {
1831            glBindTexture(GL_TEXTURE_2D, texture->id);
1832        }
1833        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1834        texture->wrapT = wrapT;
1835    }
1836}
1837
1838}; // namespace uirenderer
1839}; // namespace android
1840