OpenGLRenderer.cpp revision 5b0200bd47e8a9a4dc8d2e6c3a110d522b30bf82 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkTypeface.h>
25
26#include <utils/Log.h>
27#include <utils/StopWatch.h>
28
29#include <private/hwui/DrawGlInfo.h>
30
31#include <ui/Rect.h>
32
33#include "OpenGLRenderer.h"
34#include "DisplayListRenderer.h"
35#include "Vector.h"
36
37namespace android {
38namespace uirenderer {
39
40///////////////////////////////////////////////////////////////////////////////
41// Defines
42///////////////////////////////////////////////////////////////////////////////
43
44#define RAD_TO_DEG (180.0f / 3.14159265f)
45#define MIN_ANGLE 0.001f
46
47// TODO: This should be set in properties
48#define ALPHA_THRESHOLD (0x7f / PANEL_BIT_DEPTH)
49
50///////////////////////////////////////////////////////////////////////////////
51// Globals
52///////////////////////////////////////////////////////////////////////////////
53
54/**
55 * Structure mapping Skia xfermodes to OpenGL blending factors.
56 */
57struct Blender {
58    SkXfermode::Mode mode;
59    GLenum src;
60    GLenum dst;
61}; // struct Blender
62
63// In this array, the index of each Blender equals the value of the first
64// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
65static const Blender gBlends[] = {
66    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
67    { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
68    { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
69    { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
70    { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
71    { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
72    { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
73    { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
74    { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
75    { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
76    { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
77    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
78};
79
80// This array contains the swapped version of each SkXfermode. For instance
81// this array's SrcOver blending mode is actually DstOver. You can refer to
82// createLayer() for more information on the purpose of this array.
83static const Blender gBlendsSwap[] = {
84    { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
85    { SkXfermode::kSrc_Mode,     GL_ZERO,                 GL_ONE },
86    { SkXfermode::kDst_Mode,     GL_ONE,                  GL_ZERO },
87    { SkXfermode::kSrcOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
88    { SkXfermode::kDstOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
89    { SkXfermode::kSrcIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
90    { SkXfermode::kDstIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
91    { SkXfermode::kSrcOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
92    { SkXfermode::kDstOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
93    { SkXfermode::kSrcATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
94    { SkXfermode::kDstATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
95    { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
96};
97
98static const GLenum gTextureUnits[] = {
99    GL_TEXTURE0,
100    GL_TEXTURE1,
101    GL_TEXTURE2
102};
103
104///////////////////////////////////////////////////////////////////////////////
105// Constructors/destructor
106///////////////////////////////////////////////////////////////////////////////
107
108OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
109    mShader = NULL;
110    mColorFilter = NULL;
111    mHasShadow = false;
112
113    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
114
115    mFirstSnapshot = new Snapshot;
116}
117
118OpenGLRenderer::~OpenGLRenderer() {
119    // The context has already been destroyed at this point, do not call
120    // GL APIs. All GL state should be kept in Caches.h
121}
122
123///////////////////////////////////////////////////////////////////////////////
124// Setup
125///////////////////////////////////////////////////////////////////////////////
126
127void OpenGLRenderer::setViewport(int width, int height) {
128    glViewport(0, 0, width, height);
129    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
130
131    mWidth = width;
132    mHeight = height;
133
134    mFirstSnapshot->height = height;
135    mFirstSnapshot->viewport.set(0, 0, width, height);
136
137    mDirtyClip = false;
138}
139
140void OpenGLRenderer::prepare(bool opaque) {
141    prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
142}
143
144void OpenGLRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
145    mCaches.clearGarbage();
146
147    mSnapshot = new Snapshot(mFirstSnapshot,
148            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
149    mSnapshot->fbo = getTargetFbo();
150
151    mSaveCount = 1;
152
153    glViewport(0, 0, mWidth, mHeight);
154
155    glDisable(GL_DITHER);
156
157    glEnable(GL_SCISSOR_TEST);
158    glScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
159    mSnapshot->setClip(left, top, right, bottom);
160
161    if (!opaque) {
162        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
163        glClear(GL_COLOR_BUFFER_BIT);
164    }
165}
166
167void OpenGLRenderer::finish() {
168#if DEBUG_OPENGL
169    GLenum status = GL_NO_ERROR;
170    while ((status = glGetError()) != GL_NO_ERROR) {
171        LOGD("GL error from OpenGLRenderer: 0x%x", status);
172        switch (status) {
173            case GL_OUT_OF_MEMORY:
174                LOGE("  OpenGLRenderer is out of memory!");
175                break;
176        }
177    }
178#endif
179#if DEBUG_MEMORY_USAGE
180    mCaches.dumpMemoryUsage();
181#else
182    if (mCaches.getDebugLevel() & kDebugMemory) {
183        mCaches.dumpMemoryUsage();
184    }
185#endif
186}
187
188void OpenGLRenderer::interrupt() {
189    if (mCaches.currentProgram) {
190        if (mCaches.currentProgram->isInUse()) {
191            mCaches.currentProgram->remove();
192            mCaches.currentProgram = NULL;
193        }
194    }
195    mCaches.unbindMeshBuffer();
196}
197
198void OpenGLRenderer::resume() {
199    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
200
201    glEnable(GL_SCISSOR_TEST);
202    dirtyClip();
203
204    glDisable(GL_DITHER);
205
206    glBindFramebuffer(GL_FRAMEBUFFER, getTargetFbo());
207    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
208
209    mCaches.blend = true;
210    glEnable(GL_BLEND);
211    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
212    glBlendEquation(GL_FUNC_ADD);
213}
214
215bool OpenGLRenderer::callDrawGLFunction(Functor *functor, Rect& dirty) {
216    interrupt();
217    if (mDirtyClip) {
218        setScissorFromClip();
219    }
220
221    Rect clip(*mSnapshot->clipRect);
222    clip.snapToPixelBoundaries();
223
224#if RENDER_LAYERS_AS_REGIONS
225    // Since we don't know what the functor will draw, let's dirty
226    // tne entire clip region
227    if (hasLayer()) {
228        dirtyLayerUnchecked(clip, getRegion());
229    }
230#endif
231
232    DrawGlInfo info;
233    info.clipLeft = clip.left;
234    info.clipTop = clip.top;
235    info.clipRight = clip.right;
236    info.clipBottom = clip.bottom;
237    info.isLayer = hasLayer();
238    getSnapshot()->transform->copyTo(&info.transform[0]);
239
240    status_t result = (*functor)(0, &info);
241
242    if (result != 0) {
243        Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
244        dirty.unionWith(localDirty);
245    }
246
247    resume();
248    return result != 0;
249}
250
251///////////////////////////////////////////////////////////////////////////////
252// State management
253///////////////////////////////////////////////////////////////////////////////
254
255int OpenGLRenderer::getSaveCount() const {
256    return mSaveCount;
257}
258
259int OpenGLRenderer::save(int flags) {
260    return saveSnapshot(flags);
261}
262
263void OpenGLRenderer::restore() {
264    if (mSaveCount > 1) {
265        restoreSnapshot();
266    }
267}
268
269void OpenGLRenderer::restoreToCount(int saveCount) {
270    if (saveCount < 1) saveCount = 1;
271
272    while (mSaveCount > saveCount) {
273        restoreSnapshot();
274    }
275}
276
277int OpenGLRenderer::saveSnapshot(int flags) {
278    mSnapshot = new Snapshot(mSnapshot, flags);
279    return mSaveCount++;
280}
281
282bool OpenGLRenderer::restoreSnapshot() {
283    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
284    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
285    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
286
287    sp<Snapshot> current = mSnapshot;
288    sp<Snapshot> previous = mSnapshot->previous;
289
290    if (restoreOrtho) {
291        Rect& r = previous->viewport;
292        glViewport(r.left, r.top, r.right, r.bottom);
293        mOrthoMatrix.load(current->orthoMatrix);
294    }
295
296    mSaveCount--;
297    mSnapshot = previous;
298
299    if (restoreClip) {
300        dirtyClip();
301    }
302
303    if (restoreLayer) {
304        composeLayer(current, previous);
305    }
306
307    return restoreClip;
308}
309
310///////////////////////////////////////////////////////////////////////////////
311// Layers
312///////////////////////////////////////////////////////////////////////////////
313
314int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
315        SkPaint* p, int flags) {
316    const GLuint previousFbo = mSnapshot->fbo;
317    const int count = saveSnapshot(flags);
318
319    if (!mSnapshot->isIgnored()) {
320        int alpha = 255;
321        SkXfermode::Mode mode;
322
323        if (p) {
324            alpha = p->getAlpha();
325            if (!mCaches.extensions.hasFramebufferFetch()) {
326                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
327                if (!isMode) {
328                    // Assume SRC_OVER
329                    mode = SkXfermode::kSrcOver_Mode;
330                }
331            } else {
332                mode = getXfermode(p->getXfermode());
333            }
334        } else {
335            mode = SkXfermode::kSrcOver_Mode;
336        }
337
338        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
339    }
340
341    return count;
342}
343
344int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
345        int alpha, int flags) {
346    if (alpha >= 255 - ALPHA_THRESHOLD) {
347        return saveLayer(left, top, right, bottom, NULL, flags);
348    } else {
349        SkPaint paint;
350        paint.setAlpha(alpha);
351        return saveLayer(left, top, right, bottom, &paint, flags);
352    }
353}
354
355/**
356 * Layers are viewed by Skia are slightly different than layers in image editing
357 * programs (for instance.) When a layer is created, previously created layers
358 * and the frame buffer still receive every drawing command. For instance, if a
359 * layer is created and a shape intersecting the bounds of the layers and the
360 * framebuffer is draw, the shape will be drawn on both (unless the layer was
361 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
362 *
363 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
364 * texture. Unfortunately, this is inefficient as it requires every primitive to
365 * be drawn n + 1 times, where n is the number of active layers. In practice this
366 * means, for every primitive:
367 *   - Switch active frame buffer
368 *   - Change viewport, clip and projection matrix
369 *   - Issue the drawing
370 *
371 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
372 * To avoid this, layers are implemented in a different way here, at least in the
373 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
374 * is set. When this flag is set we can redirect all drawing operations into a
375 * single FBO.
376 *
377 * This implementation relies on the frame buffer being at least RGBA 8888. When
378 * a layer is created, only a texture is created, not an FBO. The content of the
379 * frame buffer contained within the layer's bounds is copied into this texture
380 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
381 * buffer and drawing continues as normal. This technique therefore treats the
382 * frame buffer as a scratch buffer for the layers.
383 *
384 * To compose the layers back onto the frame buffer, each layer texture
385 * (containing the original frame buffer data) is drawn as a simple quad over
386 * the frame buffer. The trick is that the quad is set as the composition
387 * destination in the blending equation, and the frame buffer becomes the source
388 * of the composition.
389 *
390 * Drawing layers with an alpha value requires an extra step before composition.
391 * An empty quad is drawn over the layer's region in the frame buffer. This quad
392 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
393 * quad is used to multiply the colors in the frame buffer. This is achieved by
394 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
395 * GL_ZERO, GL_SRC_ALPHA.
396 *
397 * Because glCopyTexImage2D() can be slow, an alternative implementation might
398 * be use to draw a single clipped layer. The implementation described above
399 * is correct in every case.
400 *
401 * (1) The frame buffer is actually not cleared right away. To allow the GPU
402 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
403 *     buffer is left untouched until the first drawing operation. Only when
404 *     something actually gets drawn are the layers regions cleared.
405 */
406bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
407        float right, float bottom, int alpha, SkXfermode::Mode mode,
408        int flags, GLuint previousFbo) {
409    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
410    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
411
412    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
413
414    // Window coordinates of the layer
415    Rect bounds(left, top, right, bottom);
416    if (!fboLayer) {
417        mSnapshot->transform->mapRect(bounds);
418
419        // Layers only make sense if they are in the framebuffer's bounds
420        if (bounds.intersect(*snapshot->clipRect)) {
421            // We cannot work with sub-pixels in this case
422            bounds.snapToPixelBoundaries();
423
424            // When the layer is not an FBO, we may use glCopyTexImage so we
425            // need to make sure the layer does not extend outside the bounds
426            // of the framebuffer
427            if (!bounds.intersect(snapshot->previous->viewport)) {
428                bounds.setEmpty();
429            }
430        } else {
431            bounds.setEmpty();
432        }
433    }
434
435    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
436            bounds.getHeight() > mCaches.maxTextureSize) {
437        snapshot->empty = fboLayer;
438    } else {
439        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
440    }
441
442    // Bail out if we won't draw in this snapshot
443    if (snapshot->invisible || snapshot->empty) {
444        return false;
445    }
446
447    glActiveTexture(gTextureUnits[0]);
448    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
449    if (!layer) {
450        return false;
451    }
452
453    layer->mode = mode;
454    layer->alpha = alpha;
455    layer->layer.set(bounds);
456    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
457            bounds.getWidth() / float(layer->width), 0.0f);
458    layer->colorFilter = mColorFilter;
459
460    // Save the layer in the snapshot
461    snapshot->flags |= Snapshot::kFlagIsLayer;
462    snapshot->layer = layer;
463
464    if (fboLayer) {
465        return createFboLayer(layer, bounds, snapshot, previousFbo);
466    } else {
467        // Copy the framebuffer into the layer
468        glBindTexture(GL_TEXTURE_2D, layer->texture);
469        if (!bounds.isEmpty()) {
470            if (layer->empty) {
471                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
472                        snapshot->height - bounds.bottom, layer->width, layer->height, 0);
473                layer->empty = false;
474            } else {
475                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
476                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
477            }
478
479            // Clear the framebuffer where the layer will draw
480            glScissor(bounds.left, mSnapshot->height - bounds.bottom,
481                    bounds.getWidth(), bounds.getHeight());
482            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
483            glClear(GL_COLOR_BUFFER_BIT);
484
485            dirtyClip();
486        }
487    }
488
489    return true;
490}
491
492bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
493        GLuint previousFbo) {
494    layer->fbo = mCaches.fboCache.get();
495
496#if RENDER_LAYERS_AS_REGIONS
497    snapshot->region = &snapshot->layer->region;
498    snapshot->flags |= Snapshot::kFlagFboTarget;
499#endif
500
501    Rect clip(bounds);
502    snapshot->transform->mapRect(clip);
503    clip.intersect(*snapshot->clipRect);
504    clip.snapToPixelBoundaries();
505    clip.intersect(snapshot->previous->viewport);
506
507    mat4 inverse;
508    inverse.loadInverse(*mSnapshot->transform);
509
510    inverse.mapRect(clip);
511    clip.snapToPixelBoundaries();
512    clip.intersect(bounds);
513    clip.translate(-bounds.left, -bounds.top);
514
515    snapshot->flags |= Snapshot::kFlagIsFboLayer;
516    snapshot->fbo = layer->fbo;
517    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
518    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
519    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
520    snapshot->height = bounds.getHeight();
521    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
522    snapshot->orthoMatrix.load(mOrthoMatrix);
523
524    // Bind texture to FBO
525    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
526    glBindTexture(GL_TEXTURE_2D, layer->texture);
527
528    // Initialize the texture if needed
529    if (layer->empty) {
530        layer->empty = false;
531        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
532                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
533    }
534
535    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
536            layer->texture, 0);
537
538#if DEBUG_LAYERS_AS_REGIONS
539    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
540    if (status != GL_FRAMEBUFFER_COMPLETE) {
541        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
542
543        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
544        glDeleteTextures(1, &layer->texture);
545        mCaches.fboCache.put(layer->fbo);
546
547        delete layer;
548
549        return false;
550    }
551#endif
552
553    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
554    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
555            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
556    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
557    glClear(GL_COLOR_BUFFER_BIT);
558
559    dirtyClip();
560
561    // Change the ortho projection
562    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
563    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
564
565    return true;
566}
567
568/**
569 * Read the documentation of createLayer() before doing anything in this method.
570 */
571void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
572    if (!current->layer) {
573        LOGE("Attempting to compose a layer that does not exist");
574        return;
575    }
576
577    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
578
579    if (fboLayer) {
580        // Unbind current FBO and restore previous one
581        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
582    }
583
584    Layer* layer = current->layer;
585    const Rect& rect = layer->layer;
586
587    if (!fboLayer && layer->alpha < 255) {
588        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
589                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
590        // Required below, composeLayerRect() will divide by 255
591        layer->alpha = 255;
592    }
593
594    mCaches.unbindMeshBuffer();
595
596    glActiveTexture(gTextureUnits[0]);
597
598    // When the layer is stored in an FBO, we can save a bit of fillrate by
599    // drawing only the dirty region
600    if (fboLayer) {
601        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
602        if (layer->colorFilter) {
603            setupColorFilter(layer->colorFilter);
604        }
605        composeLayerRegion(layer, rect);
606        if (layer->colorFilter) {
607            resetColorFilter();
608        }
609    } else {
610        if (!rect.isEmpty()) {
611            dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
612            composeLayerRect(layer, rect, true);
613        }
614    }
615
616    if (fboLayer) {
617        // Detach the texture from the FBO
618        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
619        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
620        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
621
622        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
623        mCaches.fboCache.put(current->fbo);
624    }
625
626    dirtyClip();
627
628    // Failing to add the layer to the cache should happen only if the layer is too large
629    if (!mCaches.layerCache.put(layer)) {
630        LAYER_LOGD("Deleting layer");
631        glDeleteTextures(1, &layer->texture);
632        delete layer;
633    }
634}
635
636void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
637    const Rect& texCoords = layer->texCoords;
638    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
639
640    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
641            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
642            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
643
644    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
645}
646
647void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
648#if RENDER_LAYERS_AS_REGIONS
649    if (layer->region.isRect()) {
650        const android::Rect& bounds = layer->region.getBounds();
651        layer->regionRect.set(bounds.leftTop().x, bounds.leftTop().y,
652                bounds.rightBottom().x, bounds.rightBottom().y);
653        composeLayerRect(layer, layer->regionRect);
654        layer->region.clear();
655        return;
656    }
657
658    if (!layer->region.isEmpty()) {
659        size_t count;
660        const android::Rect* rects = layer->region.getArray(&count);
661
662        const float alpha = layer->alpha / 255.0f;
663        const float texX = 1.0f / float(layer->width);
664        const float texY = 1.0f / float(layer->height);
665        const float height = rect.getHeight();
666
667        TextureVertex* mesh = mCaches.getRegionMesh();
668        GLsizei numQuads = 0;
669
670        setupDraw();
671        setupDrawWithTexture();
672        setupDrawColor(alpha, alpha, alpha, alpha);
673        setupDrawColorFilter();
674        setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
675        setupDrawProgram();
676        setupDrawDirtyRegionsDisabled();
677        setupDrawPureColorUniforms();
678        setupDrawColorFilterUniforms();
679        setupDrawTexture(layer->texture);
680        setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
681        setupDrawMesh(&mesh[0].position[0], &mesh[0].texture[0]);
682
683        for (size_t i = 0; i < count; i++) {
684            const android::Rect* r = &rects[i];
685
686            const float u1 = r->left * texX;
687            const float v1 = (height - r->top) * texY;
688            const float u2 = r->right * texX;
689            const float v2 = (height - r->bottom) * texY;
690
691            // TODO: Reject quads outside of the clip
692            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
693            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
694            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
695            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
696
697            numQuads++;
698
699            if (numQuads >= REGION_MESH_QUAD_COUNT) {
700                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
701                numQuads = 0;
702                mesh = mCaches.getRegionMesh();
703            }
704        }
705
706        if (numQuads > 0) {
707            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
708        }
709
710        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
711        finishDrawTexture();
712
713#if DEBUG_LAYERS_AS_REGIONS
714        drawRegionRects(layer->region);
715#endif
716
717        layer->region.clear();
718    }
719#else
720    composeLayerRect(layer, rect);
721#endif
722}
723
724void OpenGLRenderer::drawRegionRects(const Region& region) {
725#if DEBUG_LAYERS_AS_REGIONS
726    size_t count;
727    const android::Rect* rects = region.getArray(&count);
728
729    uint32_t colors[] = {
730            0x7fff0000, 0x7f00ff00,
731            0x7f0000ff, 0x7fff00ff,
732    };
733
734    int offset = 0;
735    int32_t top = rects[0].top;
736
737    for (size_t i = 0; i < count; i++) {
738        if (top != rects[i].top) {
739            offset ^= 0x2;
740            top = rects[i].top;
741        }
742
743        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
744        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
745                SkXfermode::kSrcOver_Mode);
746    }
747#endif
748}
749
750void OpenGLRenderer::dirtyLayer(const float left, const float top,
751        const float right, const float bottom, const mat4 transform) {
752#if RENDER_LAYERS_AS_REGIONS
753    if (hasLayer()) {
754        Rect bounds(left, top, right, bottom);
755        transform.mapRect(bounds);
756        dirtyLayerUnchecked(bounds, getRegion());
757    }
758#endif
759}
760
761void OpenGLRenderer::dirtyLayer(const float left, const float top,
762        const float right, const float bottom) {
763#if RENDER_LAYERS_AS_REGIONS
764    if (hasLayer()) {
765        Rect bounds(left, top, right, bottom);
766        dirtyLayerUnchecked(bounds, getRegion());
767    }
768#endif
769}
770
771void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
772#if RENDER_LAYERS_AS_REGIONS
773    if (bounds.intersect(*mSnapshot->clipRect)) {
774        bounds.snapToPixelBoundaries();
775        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
776        if (!dirty.isEmpty()) {
777            region->orSelf(dirty);
778        }
779    }
780#endif
781}
782
783///////////////////////////////////////////////////////////////////////////////
784// Transforms
785///////////////////////////////////////////////////////////////////////////////
786
787void OpenGLRenderer::translate(float dx, float dy) {
788    mSnapshot->transform->translate(dx, dy, 0.0f);
789}
790
791void OpenGLRenderer::rotate(float degrees) {
792    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
793}
794
795void OpenGLRenderer::scale(float sx, float sy) {
796    mSnapshot->transform->scale(sx, sy, 1.0f);
797}
798
799void OpenGLRenderer::skew(float sx, float sy) {
800    mSnapshot->transform->skew(sx, sy);
801}
802
803void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
804    mSnapshot->transform->load(*matrix);
805}
806
807const float* OpenGLRenderer::getMatrix() const {
808    if (mSnapshot->fbo != 0) {
809        return &mSnapshot->transform->data[0];
810    }
811    return &mIdentity.data[0];
812}
813
814void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
815    mSnapshot->transform->copyTo(*matrix);
816}
817
818void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
819    SkMatrix transform;
820    mSnapshot->transform->copyTo(transform);
821    transform.preConcat(*matrix);
822    mSnapshot->transform->load(transform);
823}
824
825///////////////////////////////////////////////////////////////////////////////
826// Clipping
827///////////////////////////////////////////////////////////////////////////////
828
829void OpenGLRenderer::setScissorFromClip() {
830    Rect clip(*mSnapshot->clipRect);
831    clip.snapToPixelBoundaries();
832    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
833    mDirtyClip = false;
834}
835
836const Rect& OpenGLRenderer::getClipBounds() {
837    return mSnapshot->getLocalClip();
838}
839
840bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
841    if (mSnapshot->isIgnored()) {
842        return true;
843    }
844
845    Rect r(left, top, right, bottom);
846    mSnapshot->transform->mapRect(r);
847    r.snapToPixelBoundaries();
848
849    Rect clipRect(*mSnapshot->clipRect);
850    clipRect.snapToPixelBoundaries();
851
852    return !clipRect.intersects(r);
853}
854
855bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
856    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
857    if (clipped) {
858        dirtyClip();
859    }
860    return !mSnapshot->clipRect->isEmpty();
861}
862
863///////////////////////////////////////////////////////////////////////////////
864// Drawing commands
865///////////////////////////////////////////////////////////////////////////////
866
867void OpenGLRenderer::setupDraw() {
868    if (mDirtyClip) {
869        setScissorFromClip();
870    }
871    mDescription.reset();
872    mSetShaderColor = false;
873    mColorSet = false;
874    mColorA = mColorR = mColorG = mColorB = 0.0f;
875    mTextureUnit = 0;
876    mTrackDirtyRegions = true;
877    mTexCoordsSlot = -1;
878}
879
880void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
881    mDescription.hasTexture = true;
882    mDescription.hasAlpha8Texture = isAlpha8;
883}
884
885void OpenGLRenderer::setupDrawAALine() {
886    mDescription.hasWidth = true;
887}
888
889void OpenGLRenderer::setupDrawPoint(float pointSize) {
890    mDescription.isPoint = true;
891    mDescription.pointSize = pointSize;
892}
893
894void OpenGLRenderer::setupDrawColor(int color) {
895    setupDrawColor(color, (color >> 24) & 0xFF);
896}
897
898void OpenGLRenderer::setupDrawColor(int color, int alpha) {
899    mColorA = alpha / 255.0f;
900    // BUG on this next line? a is alpha divided by 255 *twice*
901    const float a = mColorA / 255.0f;
902    mColorR = a * ((color >> 16) & 0xFF);
903    mColorG = a * ((color >>  8) & 0xFF);
904    mColorB = a * ((color      ) & 0xFF);
905    mColorSet = true;
906    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
907}
908
909void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
910    mColorA = alpha / 255.0f;
911    const float a = mColorA / 255.0f;
912    mColorR = a * ((color >> 16) & 0xFF);
913    mColorG = a * ((color >>  8) & 0xFF);
914    mColorB = a * ((color      ) & 0xFF);
915    mColorSet = true;
916    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
917}
918
919void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
920    mColorA = a;
921    mColorR = r;
922    mColorG = g;
923    mColorB = b;
924    mColorSet = true;
925    mSetShaderColor = mDescription.setColor(r, g, b, a);
926}
927
928void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
929    mColorA = a;
930    mColorR = r;
931    mColorG = g;
932    mColorB = b;
933    mColorSet = true;
934    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
935}
936
937void OpenGLRenderer::setupDrawShader() {
938    if (mShader) {
939        mShader->describe(mDescription, mCaches.extensions);
940    }
941}
942
943void OpenGLRenderer::setupDrawColorFilter() {
944    if (mColorFilter) {
945        mColorFilter->describe(mDescription, mCaches.extensions);
946    }
947}
948
949void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
950    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
951            mDescription, swapSrcDst);
952}
953
954void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
955    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
956            mDescription, swapSrcDst);
957}
958
959void OpenGLRenderer::setupDrawProgram() {
960    useProgram(mCaches.programCache.get(mDescription));
961}
962
963void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
964    mTrackDirtyRegions = false;
965}
966
967void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
968        bool ignoreTransform) {
969    mModelView.loadTranslate(left, top, 0.0f);
970    if (!ignoreTransform) {
971        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
972        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
973    } else {
974        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
975        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
976    }
977}
978
979void OpenGLRenderer::setupDrawModelViewIdentity() {
980    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
981}
982
983void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
984        bool ignoreTransform, bool ignoreModelView) {
985    if (!ignoreModelView) {
986        mModelView.loadTranslate(left, top, 0.0f);
987        mModelView.scale(right - left, bottom - top, 1.0f);
988    } else {
989        mModelView.loadIdentity();
990    }
991    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
992    if (!ignoreTransform) {
993        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
994        if (mTrackDirtyRegions && dirty) {
995            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
996        }
997    } else {
998        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
999        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
1000    }
1001}
1002
1003void OpenGLRenderer::setupDrawPointUniforms() {
1004    int slot = mCaches.currentProgram->getUniform("pointSize");
1005    glUniform1f(slot, mDescription.pointSize);
1006}
1007
1008void OpenGLRenderer::setupDrawColorUniforms() {
1009    if (mColorSet || (mShader && mSetShaderColor)) {
1010        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1011    }
1012}
1013
1014void OpenGLRenderer::setupDrawPureColorUniforms() {
1015    if (mSetShaderColor) {
1016        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1017    }
1018}
1019
1020void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1021    if (mShader) {
1022        if (ignoreTransform) {
1023            mModelView.loadInverse(*mSnapshot->transform);
1024        }
1025        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
1026    }
1027}
1028
1029void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1030    if (mShader) {
1031        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1032    }
1033}
1034
1035void OpenGLRenderer::setupDrawColorFilterUniforms() {
1036    if (mColorFilter) {
1037        mColorFilter->setupProgram(mCaches.currentProgram);
1038    }
1039}
1040
1041void OpenGLRenderer::setupDrawSimpleMesh() {
1042    mCaches.bindMeshBuffer();
1043    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1044            gMeshStride, 0);
1045}
1046
1047void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1048    bindTexture(texture);
1049    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1050
1051    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1052    glEnableVertexAttribArray(mTexCoordsSlot);
1053}
1054
1055void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1056    if (!vertices) {
1057        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1058    } else {
1059        mCaches.unbindMeshBuffer();
1060    }
1061    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1062            gMeshStride, vertices);
1063    if (mTexCoordsSlot >= 0) {
1064        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1065    }
1066}
1067
1068void OpenGLRenderer::setupDrawVertices(GLvoid* vertices) {
1069    mCaches.unbindMeshBuffer();
1070    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1071            gVertexStride, vertices);
1072}
1073
1074/**
1075 * Sets up the shader to draw an AA line. We draw AA lines with quads, where there is an
1076 * outer boundary that fades out to 0. The variables set in the shader define the width of the
1077 * core line primitive ("width") and the width of the fading boundary ("boundaryWidth"). The
1078 * "vtxDistance" attribute (one per vertex) is a value from zero to one that tells the fragment
1079 * shader where the fragment is in relation to the line width overall; this value is then used
1080 * to compute the proper color, based on whether the fragment lies in the fading AA region of
1081 * the line.
1082 */
1083void OpenGLRenderer::setupDrawAALine(GLvoid* vertices, GLvoid* distanceCoords, float strokeWidth) {
1084    mCaches.unbindMeshBuffer();
1085    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1086            gAlphaVertexStride, vertices);
1087    int distanceSlot = mCaches.currentProgram->getAttrib("vtxDistance");
1088    glEnableVertexAttribArray(distanceSlot);
1089    glVertexAttribPointer(distanceSlot, 1, GL_FLOAT, GL_FALSE, gAlphaVertexStride, distanceCoords);
1090    int widthSlot = mCaches.currentProgram->getUniform("width");
1091    int boundaryWidthSlot = mCaches.currentProgram->getUniform("boundaryWidth");
1092    int inverseBoundaryWidthSlot = mCaches.currentProgram->getUniform("inverseBoundaryWidth");
1093    float boundaryWidth = (1 - strokeWidth) / 2;
1094    glUniform1f(widthSlot, strokeWidth);
1095    glUniform1f(boundaryWidthSlot, boundaryWidth);
1096    glUniform1f(inverseBoundaryWidthSlot, (1 / boundaryWidth));
1097}
1098
1099void OpenGLRenderer::finishDrawTexture() {
1100    glDisableVertexAttribArray(mTexCoordsSlot);
1101}
1102
1103///////////////////////////////////////////////////////////////////////////////
1104// Drawing
1105///////////////////////////////////////////////////////////////////////////////
1106
1107bool OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t width, uint32_t height,
1108        Rect& dirty, uint32_t level) {
1109    if (quickReject(0.0f, 0.0f, width, height)) {
1110        return false;
1111    }
1112
1113    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1114    // will be performed by the display list itself
1115    if (displayList) {
1116        return displayList->replay(*this, dirty, level);
1117    }
1118
1119    return false;
1120}
1121
1122void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, SkPaint* paint) {
1123    int alpha;
1124    SkXfermode::Mode mode;
1125    getAlphaAndMode(paint, &alpha, &mode);
1126
1127    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1128
1129    float x = left;
1130    float y = top;
1131
1132    bool ignoreTransform = false;
1133    if (mSnapshot->transform->isPureTranslate()) {
1134        x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1135        y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1136        ignoreTransform = true;
1137    }
1138
1139    setupDraw();
1140    setupDrawWithTexture(true);
1141    if (paint) {
1142        setupDrawAlpha8Color(paint->getColor(), alpha);
1143    }
1144    setupDrawColorFilter();
1145    setupDrawShader();
1146    setupDrawBlending(true, mode);
1147    setupDrawProgram();
1148    setupDrawModelView(x, y, x + texture->width, y + texture->height, ignoreTransform);
1149    setupDrawTexture(texture->id);
1150    setupDrawPureColorUniforms();
1151    setupDrawColorFilterUniforms();
1152    setupDrawShaderUniforms();
1153    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1154
1155    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1156
1157    finishDrawTexture();
1158}
1159
1160void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1161    const float right = left + bitmap->width();
1162    const float bottom = top + bitmap->height();
1163
1164    if (quickReject(left, top, right, bottom)) {
1165        return;
1166    }
1167
1168    glActiveTexture(gTextureUnits[0]);
1169    Texture* texture = mCaches.textureCache.get(bitmap);
1170    if (!texture) return;
1171    const AutoTexture autoCleanup(texture);
1172
1173    if (bitmap->getConfig() == SkBitmap::kA8_Config) {
1174        drawAlphaBitmap(texture, left, top, paint);
1175    } else {
1176        drawTextureRect(left, top, right, bottom, texture, paint);
1177    }
1178}
1179
1180void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1181    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1182    const mat4 transform(*matrix);
1183    transform.mapRect(r);
1184
1185    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1186        return;
1187    }
1188
1189    glActiveTexture(gTextureUnits[0]);
1190    Texture* texture = mCaches.textureCache.get(bitmap);
1191    if (!texture) return;
1192    const AutoTexture autoCleanup(texture);
1193
1194    // This could be done in a cheaper way, all we need is pass the matrix
1195    // to the vertex shader. The save/restore is a bit overkill.
1196    save(SkCanvas::kMatrix_SaveFlag);
1197    concatMatrix(matrix);
1198    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1199    restore();
1200}
1201
1202void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1203        float* vertices, int* colors, SkPaint* paint) {
1204    // TODO: Do a quickReject
1205    if (!vertices || mSnapshot->isIgnored()) {
1206        return;
1207    }
1208
1209    glActiveTexture(gTextureUnits[0]);
1210    Texture* texture = mCaches.textureCache.get(bitmap);
1211    if (!texture) return;
1212    const AutoTexture autoCleanup(texture);
1213    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1214
1215    int alpha;
1216    SkXfermode::Mode mode;
1217    getAlphaAndMode(paint, &alpha, &mode);
1218
1219    const uint32_t count = meshWidth * meshHeight * 6;
1220
1221    float left = FLT_MAX;
1222    float top = FLT_MAX;
1223    float right = FLT_MIN;
1224    float bottom = FLT_MIN;
1225
1226#if RENDER_LAYERS_AS_REGIONS
1227    bool hasActiveLayer = hasLayer();
1228#else
1229    bool hasActiveLayer = false;
1230#endif
1231
1232    // TODO: Support the colors array
1233    TextureVertex mesh[count];
1234    TextureVertex* vertex = mesh;
1235    for (int32_t y = 0; y < meshHeight; y++) {
1236        for (int32_t x = 0; x < meshWidth; x++) {
1237            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1238
1239            float u1 = float(x) / meshWidth;
1240            float u2 = float(x + 1) / meshWidth;
1241            float v1 = float(y) / meshHeight;
1242            float v2 = float(y + 1) / meshHeight;
1243
1244            int ax = i + (meshWidth + 1) * 2;
1245            int ay = ax + 1;
1246            int bx = i;
1247            int by = bx + 1;
1248            int cx = i + 2;
1249            int cy = cx + 1;
1250            int dx = i + (meshWidth + 1) * 2 + 2;
1251            int dy = dx + 1;
1252
1253            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1254            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1255            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1256
1257            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1258            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1259            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1260
1261#if RENDER_LAYERS_AS_REGIONS
1262            if (hasActiveLayer) {
1263                // TODO: This could be optimized to avoid unnecessary ops
1264                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1265                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1266                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1267                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1268            }
1269#endif
1270        }
1271    }
1272
1273#if RENDER_LAYERS_AS_REGIONS
1274    if (hasActiveLayer) {
1275        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1276    }
1277#endif
1278
1279    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1280            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1281            GL_TRIANGLES, count, false, false, 0, false, false);
1282}
1283
1284void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1285         float srcLeft, float srcTop, float srcRight, float srcBottom,
1286         float dstLeft, float dstTop, float dstRight, float dstBottom,
1287         SkPaint* paint) {
1288    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1289        return;
1290    }
1291
1292    glActiveTexture(gTextureUnits[0]);
1293    Texture* texture = mCaches.textureCache.get(bitmap);
1294    if (!texture) return;
1295    const AutoTexture autoCleanup(texture);
1296    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1297
1298    const float width = texture->width;
1299    const float height = texture->height;
1300
1301    const float u1 = srcLeft / width;
1302    const float v1 = srcTop / height;
1303    const float u2 = srcRight / width;
1304    const float v2 = srcBottom / height;
1305
1306    mCaches.unbindMeshBuffer();
1307    resetDrawTextureTexCoords(u1, v1, u2, v2);
1308
1309    int alpha;
1310    SkXfermode::Mode mode;
1311    getAlphaAndMode(paint, &alpha, &mode);
1312
1313    if (mSnapshot->transform->isPureTranslate()) {
1314        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1315        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1316
1317        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1318                texture->id, alpha / 255.0f, mode, texture->blend,
1319                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1320                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1321    } else {
1322        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1323                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1324                GL_TRIANGLE_STRIP, gMeshCount);
1325    }
1326
1327    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1328}
1329
1330void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1331        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1332        float left, float top, float right, float bottom, SkPaint* paint) {
1333    if (quickReject(left, top, right, bottom)) {
1334        return;
1335    }
1336
1337    glActiveTexture(gTextureUnits[0]);
1338    Texture* texture = mCaches.textureCache.get(bitmap);
1339    if (!texture) return;
1340    const AutoTexture autoCleanup(texture);
1341    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1342
1343    int alpha;
1344    SkXfermode::Mode mode;
1345    getAlphaAndMode(paint, &alpha, &mode);
1346
1347    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1348            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1349
1350    if (mesh && mesh->verticesCount > 0) {
1351        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1352#if RENDER_LAYERS_AS_REGIONS
1353        // Mark the current layer dirty where we are going to draw the patch
1354        if (hasLayer() && mesh->hasEmptyQuads) {
1355            const float offsetX = left + mSnapshot->transform->getTranslateX();
1356            const float offsetY = top + mSnapshot->transform->getTranslateY();
1357            const size_t count = mesh->quads.size();
1358            for (size_t i = 0; i < count; i++) {
1359                const Rect& bounds = mesh->quads.itemAt(i);
1360                if (pureTranslate) {
1361                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1362                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1363                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1364                } else {
1365                    dirtyLayer(left + bounds.left, top + bounds.top,
1366                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1367                }
1368            }
1369        }
1370#endif
1371
1372        if (pureTranslate) {
1373            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1374            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1375
1376            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1377                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1378                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1379                    true, !mesh->hasEmptyQuads);
1380        } else {
1381            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1382                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1383                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1384                    true, !mesh->hasEmptyQuads);
1385        }
1386    }
1387}
1388
1389void OpenGLRenderer::drawLinesAsQuads(float *points, int count, bool isAA, bool isHairline,
1390        float strokeWidth) {
1391    int verticesCount = count;
1392    if (count > 4) {
1393        // Polyline: account for extra vertices needed for continous tri-strip
1394        verticesCount += (count -4);
1395    }
1396    if (isAA) {
1397        // Expand boundary to enable AA calculations on the quad border
1398        strokeWidth += .5f;
1399    }
1400    Vertex lines[verticesCount];
1401    Vertex* vertices = &lines[0];
1402    AlphaVertex wLines[verticesCount];
1403    AlphaVertex* aaVertices = &wLines[0];
1404    if (!isAA) {
1405        setupDrawVertices(vertices);
1406    } else {
1407        void *alphaCoords = ((void*) aaVertices) + gVertexAlphaOffset;
1408        // innerProportion is the ratio of the inner (non-AA) port of the line to the total
1409        // AA stroke width (the base stroke width expanded by a half pixel on either side).
1410        // This value is used in the fragment shader to determine how to fill fragments.
1411        float innerProportion = fmax(strokeWidth - 1.0f, 0) / (strokeWidth + .5f);
1412        setupDrawAALine((void*) aaVertices, (void*) alphaCoords, innerProportion);
1413    }
1414
1415    int generatedVerticesCount = 0;
1416    AlphaVertex *prevAAVertex = NULL;
1417    Vertex *prevVertex = NULL;
1418    float inverseScaleX, inverseScaleY;
1419    if (isHairline) {
1420        // The quad that we use for AA hairlines needs to account for scaling because the line
1421        // should always be one pixel wide regardless of scale.
1422        inverseScaleX = 1.0f;
1423        inverseScaleY = 1.0f;
1424        if (!mSnapshot->transform->isPureTranslate()) {
1425            Matrix4 *mat = mSnapshot->transform;
1426            float m00 = mat->data[Matrix4::kScaleX];
1427            float m01 = mat->data[Matrix4::kSkewY];
1428            float m02 = mat->data[2];
1429            float m10 = mat->data[Matrix4::kSkewX];
1430            float m11 = mat->data[Matrix4::kScaleX];
1431            float m12 = mat->data[6];
1432            float scaleX = sqrt(m00*m00 + m01*m01);
1433            float scaleY = sqrt(m10*m10 + m11*m11);
1434            inverseScaleX = (scaleX != 0) ? (inverseScaleX / scaleX) : 0;
1435            inverseScaleY = (scaleY != 0) ? (inverseScaleY / scaleY) : 0;
1436        }
1437    }
1438    for (int i = 0; i < count; i += 4) {
1439        // a = start point, b = end point
1440        vec2 a(points[i], points[i + 1]);
1441        vec2 b(points[i + 2], points[i + 3]);
1442
1443        // Bias to snap to the same pixels as Skia
1444        a += 0.375;
1445        b += 0.375;
1446
1447        // Find the normal to the line
1448        vec2 n = (b - a).copyNormalized() * strokeWidth;
1449        if (isHairline) {
1450            float wideningFactor;
1451            if (fabs(n.x) >= fabs(n.y)) {
1452                wideningFactor = fabs(1.0f / n.x);
1453            } else {
1454                wideningFactor = fabs(1.0f / n.y);
1455            }
1456            n.x *= inverseScaleX;
1457            n.y *= inverseScaleY;
1458            n *= wideningFactor;
1459        }
1460        float x = n.x;
1461        n.x = -n.y;
1462        n.y = x;
1463
1464        // Four corners of the rectangle defining a thick line
1465        vec2 p1 = a - n;
1466        vec2 p2 = a + n;
1467        vec2 p3 = b + n;
1468        vec2 p4 = b - n;
1469
1470        const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1471        const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1472        const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1473        const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1474
1475        if (!quickReject(left, top, right, bottom)) {
1476            // Draw the line as 2 triangles, could be optimized
1477            // by using only 4 vertices and the correct indices
1478            // Also we should probably used non textured vertices
1479            // when line AA is disabled to save on bandwidth
1480            if (!isAA) {
1481                if (prevVertex != NULL) {
1482                    // Issue two repeat vertices to create degenerate triangles to bridge
1483                    // between the previous line and the new one. This is necessary because
1484                    // we are creating a single triangle_strip which will contain
1485                    // potentially discontinuous line segments.
1486                    Vertex::set(vertices++, prevVertex->position[0], prevVertex->position[1]);
1487                    Vertex::set(vertices++, p1.x, p1.y);
1488                    generatedVerticesCount += 2;
1489                }
1490                Vertex::set(vertices++, p1.x, p1.y);
1491                Vertex::set(vertices++, p2.x, p2.y);
1492                Vertex::set(vertices++, p4.x, p4.y);
1493                Vertex::set(vertices++, p3.x, p3.y);
1494                prevVertex = vertices - 1;
1495                generatedVerticesCount += 4;
1496            } else {
1497                if (prevAAVertex != NULL) {
1498                    // Issue two repeat vertices to create degenerate triangles to bridge
1499                    // between the previous line and the new one. This is necessary because
1500                    // we are creating a single triangle_strip which will contain
1501                    // potentially discontinuous line segments.
1502                    AlphaVertex::set(aaVertices++,prevAAVertex->position[0],
1503                            prevAAVertex->position[1], prevAAVertex->alpha);
1504                    AlphaVertex::set(aaVertices++, p4.x, p4.y, 1);
1505                    generatedVerticesCount += 2;
1506                }
1507                AlphaVertex::set(aaVertices++, p4.x, p4.y, 1);
1508                AlphaVertex::set(aaVertices++, p1.x, p1.y, 1);
1509                AlphaVertex::set(aaVertices++, p3.x, p3.y, 0);
1510                AlphaVertex::set(aaVertices++, p2.x, p2.y, 0);
1511                prevAAVertex = aaVertices - 1;
1512                generatedVerticesCount += 4;
1513            }
1514            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1515        }
1516    }
1517    if (generatedVerticesCount > 0) {
1518       glDrawArrays(GL_TRIANGLE_STRIP, 0, generatedVerticesCount);
1519    }
1520}
1521
1522void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1523    if (mSnapshot->isIgnored()) return;
1524
1525    const bool isAA = paint->isAntiAlias();
1526    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1527    // A stroke width of 0 has a special meaning in Skia:
1528    // it draws a line 1 px wide regardless of current transform
1529    bool isHairLine = paint->getStrokeWidth() == 0.0f;
1530
1531    int alpha;
1532    SkXfermode::Mode mode;
1533    getAlphaAndMode(paint, &alpha, &mode);
1534    int generatedVerticesCount = 0;
1535
1536    setupDraw();
1537    if (isAA) {
1538        setupDrawAALine();
1539    }
1540    setupDrawColor(paint->getColor(), alpha);
1541    setupDrawColorFilter();
1542    setupDrawShader();
1543    if (isAA) {
1544        setupDrawBlending(true, mode);
1545    } else {
1546        setupDrawBlending(mode);
1547    }
1548    setupDrawProgram();
1549    setupDrawModelViewIdentity();
1550    setupDrawColorUniforms();
1551    setupDrawColorFilterUniforms();
1552    setupDrawShaderIdentityUniforms();
1553
1554    if (!isHairLine) {
1555        drawLinesAsQuads(points, count, isAA, isHairLine, strokeWidth);
1556    } else {
1557        if (isAA) {
1558            drawLinesAsQuads(points, count, isAA, isHairLine, .5f);
1559        } else {
1560            int verticesCount = count >> 1;
1561            Vertex lines[verticesCount];
1562            Vertex* vertices = &lines[0];
1563            setupDrawVertices(vertices);
1564            for (int i = 0; i < count; i += 4) {
1565
1566                const float left = fmin(points[i], points[i + 2]);
1567                const float right = fmax(points[i], points[i + 2]);
1568                const float top = fmin(points[i + 1], points[i + 3]);
1569                const float bottom = fmax(points[i + 1], points[i + 3]);
1570
1571                Vertex::set(vertices++, points[i], points[i + 1]);
1572                Vertex::set(vertices++, points[i + 2], points[i + 3]);
1573                generatedVerticesCount += 2;
1574                dirtyLayer(left, top,
1575                        right == left ? left + 1 : right, bottom == top ? top + 1 : bottom,
1576                        *mSnapshot->transform);
1577            }
1578
1579            glLineWidth(1.0f);
1580            glDrawArrays(GL_LINES, 0, generatedVerticesCount);
1581        }
1582    }
1583}
1584
1585void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) {
1586    if (mSnapshot->isIgnored()) return;
1587
1588    // TODO: The paint's cap style defines whether the points are square or circular
1589    // TODO: Handle AA for round points
1590
1591    // A stroke width of 0 has a special meaning in Skia:
1592    // it draws an unscaled 1px point
1593    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1594
1595    int alpha;
1596    SkXfermode::Mode mode;
1597    getAlphaAndMode(paint, &alpha, &mode);
1598
1599    int verticesCount = count >> 1;
1600    int generatedVerticesCount = 0;
1601
1602    TextureVertex pointsData[verticesCount];
1603    TextureVertex* vertex = &pointsData[0];
1604
1605    setupDraw();
1606    setupDrawPoint(isHairLine ? 1.0f : paint->getStrokeWidth());
1607    setupDrawColor(paint->getColor(), alpha);
1608    setupDrawColorFilter();
1609    setupDrawShader();
1610    setupDrawBlending(mode);
1611    setupDrawProgram();
1612    setupDrawModelViewIdentity();
1613    setupDrawColorUniforms();
1614    setupDrawColorFilterUniforms();
1615    setupDrawPointUniforms();
1616    setupDrawShaderIdentityUniforms();
1617    setupDrawMesh(vertex);
1618
1619    for (int i = 0; i < count; i += 2) {
1620        TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1621        generatedVerticesCount++;
1622    }
1623
1624    glDrawArrays(GL_POINTS, 0, generatedVerticesCount);
1625}
1626
1627void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1628    // No need to check against the clip, we fill the clip region
1629    if (mSnapshot->isIgnored()) return;
1630
1631    Rect& clip(*mSnapshot->clipRect);
1632    clip.snapToPixelBoundaries();
1633
1634    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1635}
1636
1637void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
1638    if (!texture) return;
1639    const AutoTexture autoCleanup(texture);
1640
1641    const float x = left + texture->left - texture->offset;
1642    const float y = top + texture->top - texture->offset;
1643
1644    drawPathTexture(texture, x, y, paint);
1645}
1646
1647void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
1648        float rx, float ry, SkPaint* paint) {
1649    if (mSnapshot->isIgnored()) return;
1650
1651    glActiveTexture(gTextureUnits[0]);
1652    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
1653            right - left, bottom - top, rx, ry, paint);
1654    drawShape(left, top, texture, paint);
1655}
1656
1657void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
1658    if (mSnapshot->isIgnored()) return;
1659
1660    glActiveTexture(gTextureUnits[0]);
1661    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
1662    drawShape(x - radius, y - radius, texture, paint);
1663}
1664
1665void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
1666    if (mSnapshot->isIgnored()) return;
1667
1668    glActiveTexture(gTextureUnits[0]);
1669    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
1670    drawShape(left, top, texture, paint);
1671}
1672
1673void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
1674        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
1675    if (mSnapshot->isIgnored()) return;
1676
1677    if (fabs(sweepAngle) >= 360.0f) {
1678        drawOval(left, top, right, bottom, paint);
1679        return;
1680    }
1681
1682    glActiveTexture(gTextureUnits[0]);
1683    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
1684            startAngle, sweepAngle, useCenter, paint);
1685    drawShape(left, top, texture, paint);
1686}
1687
1688void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
1689        SkPaint* paint) {
1690    if (mSnapshot->isIgnored()) return;
1691
1692    glActiveTexture(gTextureUnits[0]);
1693    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
1694    drawShape(left, top, texture, paint);
1695}
1696
1697void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1698    if (p->getStyle() != SkPaint::kFill_Style) {
1699        drawRectAsShape(left, top, right, bottom, p);
1700        return;
1701    }
1702
1703    if (quickReject(left, top, right, bottom)) {
1704        return;
1705    }
1706
1707    SkXfermode::Mode mode;
1708    if (!mCaches.extensions.hasFramebufferFetch()) {
1709        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1710        if (!isMode) {
1711            // Assume SRC_OVER
1712            mode = SkXfermode::kSrcOver_Mode;
1713        }
1714    } else {
1715        mode = getXfermode(p->getXfermode());
1716    }
1717
1718    int color = p->getColor();
1719    drawColorRect(left, top, right, bottom, color, mode);
1720}
1721
1722void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1723        float x, float y, SkPaint* paint) {
1724    if (text == NULL || count == 0) {
1725        return;
1726    }
1727    if (mSnapshot->isIgnored()) return;
1728
1729    paint->setAntiAlias(true);
1730
1731    float length = -1.0f;
1732    switch (paint->getTextAlign()) {
1733        case SkPaint::kCenter_Align:
1734            length = paint->measureText(text, bytesCount);
1735            x -= length / 2.0f;
1736            break;
1737        case SkPaint::kRight_Align:
1738            length = paint->measureText(text, bytesCount);
1739            x -= length;
1740            break;
1741        default:
1742            break;
1743    }
1744
1745    const float oldX = x;
1746    const float oldY = y;
1747    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1748    if (pureTranslate) {
1749        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1750        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1751    }
1752
1753    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1754    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1755            paint->getTextSize());
1756
1757    int alpha;
1758    SkXfermode::Mode mode;
1759    getAlphaAndMode(paint, &alpha, &mode);
1760
1761    if (mHasShadow) {
1762        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1763        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1764                count, mShadowRadius);
1765        const AutoTexture autoCleanup(shadow);
1766
1767        const float sx = x - shadow->left + mShadowDx;
1768        const float sy = y - shadow->top + mShadowDy;
1769
1770        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1771
1772        glActiveTexture(gTextureUnits[0]);
1773        setupDraw();
1774        setupDrawWithTexture(true);
1775        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1776        setupDrawBlending(true, mode);
1777        setupDrawProgram();
1778        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1779        setupDrawTexture(shadow->id);
1780        setupDrawPureColorUniforms();
1781        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1782
1783        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1784        finishDrawTexture();
1785    }
1786
1787    if (paint->getAlpha() == 0 && paint->getXfermode() == NULL) {
1788        return;
1789    }
1790
1791    // Pick the appropriate texture filtering
1792    bool linearFilter = mSnapshot->transform->changesBounds();
1793    if (pureTranslate && !linearFilter) {
1794        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1795    }
1796
1797    glActiveTexture(gTextureUnits[0]);
1798    setupDraw();
1799    setupDrawDirtyRegionsDisabled();
1800    setupDrawWithTexture(true);
1801    setupDrawAlpha8Color(paint->getColor(), alpha);
1802    setupDrawColorFilter();
1803    setupDrawShader();
1804    setupDrawBlending(true, mode);
1805    setupDrawProgram();
1806    setupDrawModelView(x, y, x, y, pureTranslate, true);
1807    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1808    setupDrawPureColorUniforms();
1809    setupDrawColorFilterUniforms();
1810    setupDrawShaderUniforms(pureTranslate);
1811
1812    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1813    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1814
1815#if RENDER_LAYERS_AS_REGIONS
1816    bool hasActiveLayer = hasLayer();
1817#else
1818    bool hasActiveLayer = false;
1819#endif
1820    mCaches.unbindMeshBuffer();
1821
1822    // Tell font renderer the locations of position and texture coord
1823    // attributes so it can bind its data properly
1824    int positionSlot = mCaches.currentProgram->position;
1825    fontRenderer.setAttributeBindingSlots(positionSlot, mTexCoordsSlot);
1826    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1827            hasActiveLayer ? &bounds : NULL)) {
1828#if RENDER_LAYERS_AS_REGIONS
1829        if (hasActiveLayer) {
1830            if (!pureTranslate) {
1831                mSnapshot->transform->mapRect(bounds);
1832            }
1833            dirtyLayerUnchecked(bounds, getRegion());
1834        }
1835#endif
1836    }
1837
1838    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1839    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1840
1841    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1842}
1843
1844void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1845    if (mSnapshot->isIgnored()) return;
1846
1847    glActiveTexture(gTextureUnits[0]);
1848
1849    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1850    if (!texture) return;
1851    const AutoTexture autoCleanup(texture);
1852
1853    const float x = texture->left - texture->offset;
1854    const float y = texture->top - texture->offset;
1855
1856    drawPathTexture(texture, x, y, paint);
1857}
1858
1859void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
1860    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
1861        return;
1862    }
1863
1864    glActiveTexture(gTextureUnits[0]);
1865
1866    int alpha;
1867    SkXfermode::Mode mode;
1868    getAlphaAndMode(paint, &alpha, &mode);
1869
1870    layer->alpha = alpha;
1871    layer->mode = mode;
1872
1873#if RENDER_LAYERS_AS_REGIONS
1874    if (!layer->region.isEmpty()) {
1875        if (layer->region.isRect()) {
1876            composeLayerRect(layer, layer->regionRect);
1877        } else if (layer->mesh) {
1878            const float a = alpha / 255.0f;
1879            const Rect& rect = layer->layer;
1880
1881            setupDraw();
1882            setupDrawWithTexture();
1883            setupDrawColor(a, a, a, a);
1884            setupDrawColorFilter();
1885            setupDrawBlending(layer->blend || layer->alpha < 255, layer->mode, false);
1886            setupDrawProgram();
1887            setupDrawModelViewTranslate(x, y,
1888                    x + layer->layer.getWidth(), y + layer->layer.getHeight());
1889            setupDrawPureColorUniforms();
1890            setupDrawColorFilterUniforms();
1891            setupDrawTexture(layer->texture);
1892            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
1893
1894            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
1895                    GL_UNSIGNED_SHORT, layer->meshIndices);
1896
1897            finishDrawTexture();
1898
1899#if DEBUG_LAYERS_AS_REGIONS
1900            drawRegionRects(layer->region);
1901#endif
1902        }
1903    }
1904#else
1905    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
1906    composeLayerRect(layer, r);
1907#endif
1908}
1909
1910///////////////////////////////////////////////////////////////////////////////
1911// Shaders
1912///////////////////////////////////////////////////////////////////////////////
1913
1914void OpenGLRenderer::resetShader() {
1915    mShader = NULL;
1916}
1917
1918void OpenGLRenderer::setupShader(SkiaShader* shader) {
1919    mShader = shader;
1920    if (mShader) {
1921        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1922    }
1923}
1924
1925///////////////////////////////////////////////////////////////////////////////
1926// Color filters
1927///////////////////////////////////////////////////////////////////////////////
1928
1929void OpenGLRenderer::resetColorFilter() {
1930    mColorFilter = NULL;
1931}
1932
1933void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1934    mColorFilter = filter;
1935}
1936
1937///////////////////////////////////////////////////////////////////////////////
1938// Drop shadow
1939///////////////////////////////////////////////////////////////////////////////
1940
1941void OpenGLRenderer::resetShadow() {
1942    mHasShadow = false;
1943}
1944
1945void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1946    mHasShadow = true;
1947    mShadowRadius = radius;
1948    mShadowDx = dx;
1949    mShadowDy = dy;
1950    mShadowColor = color;
1951}
1952
1953///////////////////////////////////////////////////////////////////////////////
1954// Drawing implementation
1955///////////////////////////////////////////////////////////////////////////////
1956
1957void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
1958        float x, float y, SkPaint* paint) {
1959    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1960        return;
1961    }
1962
1963    int alpha;
1964    SkXfermode::Mode mode;
1965    getAlphaAndMode(paint, &alpha, &mode);
1966
1967    setupDraw();
1968    setupDrawWithTexture(true);
1969    setupDrawAlpha8Color(paint->getColor(), alpha);
1970    setupDrawColorFilter();
1971    setupDrawShader();
1972    setupDrawBlending(true, mode);
1973    setupDrawProgram();
1974    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1975    setupDrawTexture(texture->id);
1976    setupDrawPureColorUniforms();
1977    setupDrawColorFilterUniforms();
1978    setupDrawShaderUniforms();
1979    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1980
1981    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1982
1983    finishDrawTexture();
1984}
1985
1986// Same values used by Skia
1987#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1988#define kStdUnderline_Offset    (1.0f / 9.0f)
1989#define kStdUnderline_Thickness (1.0f / 18.0f)
1990
1991void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1992        float x, float y, SkPaint* paint) {
1993    // Handle underline and strike-through
1994    uint32_t flags = paint->getFlags();
1995    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1996        float underlineWidth = length;
1997        // If length is > 0.0f, we already measured the text for the text alignment
1998        if (length <= 0.0f) {
1999            underlineWidth = paint->measureText(text, bytesCount);
2000        }
2001
2002        float offsetX = 0;
2003        switch (paint->getTextAlign()) {
2004            case SkPaint::kCenter_Align:
2005                offsetX = underlineWidth * 0.5f;
2006                break;
2007            case SkPaint::kRight_Align:
2008                offsetX = underlineWidth;
2009                break;
2010            default:
2011                break;
2012        }
2013
2014        if (underlineWidth > 0.0f) {
2015            const float textSize = paint->getTextSize();
2016            // TODO: Support stroke width < 1.0f when we have AA lines
2017            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
2018
2019            const float left = x - offsetX;
2020            float top = 0.0f;
2021
2022            int linesCount = 0;
2023            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
2024            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
2025
2026            const int pointsCount = 4 * linesCount;
2027            float points[pointsCount];
2028            int currentPoint = 0;
2029
2030            if (flags & SkPaint::kUnderlineText_Flag) {
2031                top = y + textSize * kStdUnderline_Offset;
2032                points[currentPoint++] = left;
2033                points[currentPoint++] = top;
2034                points[currentPoint++] = left + underlineWidth;
2035                points[currentPoint++] = top;
2036            }
2037
2038            if (flags & SkPaint::kStrikeThruText_Flag) {
2039                top = y + textSize * kStdStrikeThru_Offset;
2040                points[currentPoint++] = left;
2041                points[currentPoint++] = top;
2042                points[currentPoint++] = left + underlineWidth;
2043                points[currentPoint++] = top;
2044            }
2045
2046            SkPaint linesPaint(*paint);
2047            linesPaint.setStrokeWidth(strokeWidth);
2048
2049            drawLines(&points[0], pointsCount, &linesPaint);
2050        }
2051    }
2052}
2053
2054void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
2055        int color, SkXfermode::Mode mode, bool ignoreTransform) {
2056    // If a shader is set, preserve only the alpha
2057    if (mShader) {
2058        color |= 0x00ffffff;
2059    }
2060
2061    setupDraw();
2062    setupDrawColor(color);
2063    setupDrawShader();
2064    setupDrawColorFilter();
2065    setupDrawBlending(mode);
2066    setupDrawProgram();
2067    setupDrawModelView(left, top, right, bottom, ignoreTransform);
2068    setupDrawColorUniforms();
2069    setupDrawShaderUniforms(ignoreTransform);
2070    setupDrawColorFilterUniforms();
2071    setupDrawSimpleMesh();
2072
2073    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2074}
2075
2076void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2077        Texture* texture, SkPaint* paint) {
2078    int alpha;
2079    SkXfermode::Mode mode;
2080    getAlphaAndMode(paint, &alpha, &mode);
2081
2082    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
2083
2084    if (mSnapshot->transform->isPureTranslate()) {
2085        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
2086        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
2087
2088        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
2089                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
2090                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
2091    } else {
2092        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
2093                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
2094                GL_TRIANGLE_STRIP, gMeshCount);
2095    }
2096}
2097
2098void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2099        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
2100    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
2101            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
2102}
2103
2104void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
2105        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
2106        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
2107        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
2108
2109    setupDraw();
2110    setupDrawWithTexture();
2111    setupDrawColor(alpha, alpha, alpha, alpha);
2112    setupDrawColorFilter();
2113    setupDrawBlending(blend, mode, swapSrcDst);
2114    setupDrawProgram();
2115    if (!dirty) {
2116        setupDrawDirtyRegionsDisabled();
2117    }
2118    if (!ignoreScale) {
2119        setupDrawModelView(left, top, right, bottom, ignoreTransform);
2120    } else {
2121        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
2122    }
2123    setupDrawPureColorUniforms();
2124    setupDrawColorFilterUniforms();
2125    setupDrawTexture(texture);
2126    setupDrawMesh(vertices, texCoords, vbo);
2127
2128    glDrawArrays(drawMode, 0, elementsCount);
2129
2130    finishDrawTexture();
2131}
2132
2133void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
2134        ProgramDescription& description, bool swapSrcDst) {
2135    blend = blend || mode != SkXfermode::kSrcOver_Mode;
2136    if (blend) {
2137        if (mode < SkXfermode::kPlus_Mode) {
2138            if (!mCaches.blend) {
2139                glEnable(GL_BLEND);
2140            }
2141
2142            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
2143            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
2144
2145            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
2146                glBlendFunc(sourceMode, destMode);
2147                mCaches.lastSrcMode = sourceMode;
2148                mCaches.lastDstMode = destMode;
2149            }
2150        } else {
2151            // These blend modes are not supported by OpenGL directly and have
2152            // to be implemented using shaders. Since the shader will perform
2153            // the blending, turn blending off here
2154            if (mCaches.extensions.hasFramebufferFetch()) {
2155                description.framebufferMode = mode;
2156                description.swapSrcDst = swapSrcDst;
2157            }
2158
2159            if (mCaches.blend) {
2160                glDisable(GL_BLEND);
2161            }
2162            blend = false;
2163        }
2164    } else if (mCaches.blend) {
2165        glDisable(GL_BLEND);
2166    }
2167    mCaches.blend = blend;
2168}
2169
2170bool OpenGLRenderer::useProgram(Program* program) {
2171    if (!program->isInUse()) {
2172        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
2173        program->use();
2174        mCaches.currentProgram = program;
2175        return false;
2176    }
2177    return true;
2178}
2179
2180void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
2181    TextureVertex* v = &mMeshVertices[0];
2182    TextureVertex::setUV(v++, u1, v1);
2183    TextureVertex::setUV(v++, u2, v1);
2184    TextureVertex::setUV(v++, u1, v2);
2185    TextureVertex::setUV(v++, u2, v2);
2186}
2187
2188void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
2189    if (paint) {
2190        if (!mCaches.extensions.hasFramebufferFetch()) {
2191            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
2192            if (!isMode) {
2193                // Assume SRC_OVER
2194                *mode = SkXfermode::kSrcOver_Mode;
2195            }
2196        } else {
2197            *mode = getXfermode(paint->getXfermode());
2198        }
2199
2200        // Skia draws using the color's alpha channel if < 255
2201        // Otherwise, it uses the paint's alpha
2202        int color = paint->getColor();
2203        *alpha = (color >> 24) & 0xFF;
2204        if (*alpha == 255) {
2205            *alpha = paint->getAlpha();
2206        }
2207    } else {
2208        *mode = SkXfermode::kSrcOver_Mode;
2209        *alpha = 255;
2210    }
2211}
2212
2213SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
2214    // In the future we should look at unifying the Porter-Duff modes and
2215    // SkXferModes so that we can use SkXfermode::IsMode(xfer, &mode).
2216    if (mode == NULL) {
2217        return SkXfermode::kSrcOver_Mode;
2218    }
2219    return mode->fMode;
2220}
2221
2222void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
2223    bool bound = false;
2224    if (wrapS != texture->wrapS) {
2225        glBindTexture(GL_TEXTURE_2D, texture->id);
2226        bound = true;
2227        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
2228        texture->wrapS = wrapS;
2229    }
2230    if (wrapT != texture->wrapT) {
2231        if (!bound) {
2232            glBindTexture(GL_TEXTURE_2D, texture->id);
2233        }
2234        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
2235        texture->wrapT = wrapT;
2236    }
2237}
2238
2239}; // namespace uirenderer
2240}; // namespace android
2241