OpenGLRenderer.cpp revision e2eaf6997d429249904f842092b075f3da92c5be 
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 <SkPathMeasure.h>
25#include <SkTypeface.h>
26
27#include <utils/Log.h>
28#include <utils/StopWatch.h>
29
30#include <private/hwui/DrawGlInfo.h>
31
32#include <ui/Rect.h>
33
34#include "OpenGLRenderer.h"
35#include "DisplayListRenderer.h"
36#include "Vector.h"
37
38namespace android {
39namespace uirenderer {
40
41///////////////////////////////////////////////////////////////////////////////
42// Defines
43///////////////////////////////////////////////////////////////////////////////
44
45#define RAD_TO_DEG (180.0f / 3.14159265f)
46#define MIN_ANGLE 0.001f
47
48// TODO: This should be set in properties
49#define ALPHA_THRESHOLD (0x7f / PANEL_BIT_DEPTH)
50
51#define FILTER(paint) (paint && paint->isFilterBitmap() ? GL_LINEAR : GL_NEAREST)
52
53///////////////////////////////////////////////////////////////////////////////
54// Globals
55///////////////////////////////////////////////////////////////////////////////
56
57/**
58 * Structure mapping Skia xfermodes to OpenGL blending factors.
59 */
60struct Blender {
61    SkXfermode::Mode mode;
62    GLenum src;
63    GLenum dst;
64}; // struct Blender
65
66// In this array, the index of each Blender equals the value of the first
67// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
68static const Blender gBlends[] = {
69    { SkXfermode::kClear_Mode,    GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
70    { SkXfermode::kSrc_Mode,      GL_ONE,                 GL_ZERO },
71    { SkXfermode::kDst_Mode,      GL_ZERO,                GL_ONE },
72    { SkXfermode::kSrcOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
73    { SkXfermode::kDstOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
74    { SkXfermode::kSrcIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
75    { SkXfermode::kDstIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
76    { SkXfermode::kSrcOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
77    { SkXfermode::kDstOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
78    { SkXfermode::kSrcATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
79    { SkXfermode::kDstATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
80    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
81    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
82    { SkXfermode::kMultiply_Mode, GL_ZERO,                GL_SRC_COLOR },
83    { SkXfermode::kScreen_Mode,   GL_ONE,                 GL_ONE_MINUS_SRC_COLOR }
84};
85
86// This array contains the swapped version of each SkXfermode. For instance
87// this array's SrcOver blending mode is actually DstOver. You can refer to
88// createLayer() for more information on the purpose of this array.
89static const Blender gBlendsSwap[] = {
90    { SkXfermode::kClear_Mode,    GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
91    { SkXfermode::kSrc_Mode,      GL_ZERO,                GL_ONE },
92    { SkXfermode::kDst_Mode,      GL_ONE,                 GL_ZERO },
93    { SkXfermode::kSrcOver_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_ONE },
94    { SkXfermode::kDstOver_Mode,  GL_ONE,                 GL_ONE_MINUS_SRC_ALPHA },
95    { SkXfermode::kSrcIn_Mode,    GL_ZERO,                GL_SRC_ALPHA },
96    { SkXfermode::kDstIn_Mode,    GL_DST_ALPHA,           GL_ZERO },
97    { SkXfermode::kSrcOut_Mode,   GL_ZERO,                GL_ONE_MINUS_SRC_ALPHA },
98    { SkXfermode::kDstOut_Mode,   GL_ONE_MINUS_DST_ALPHA, GL_ZERO },
99    { SkXfermode::kSrcATop_Mode,  GL_ONE_MINUS_DST_ALPHA, GL_SRC_ALPHA },
100    { SkXfermode::kDstATop_Mode,  GL_DST_ALPHA,           GL_ONE_MINUS_SRC_ALPHA },
101    { SkXfermode::kXor_Mode,      GL_ONE_MINUS_DST_ALPHA, GL_ONE_MINUS_SRC_ALPHA },
102    { SkXfermode::kPlus_Mode,     GL_ONE,                 GL_ONE },
103    { SkXfermode::kMultiply_Mode, GL_DST_COLOR,           GL_ZERO },
104    { SkXfermode::kScreen_Mode,   GL_ONE_MINUS_DST_COLOR, GL_ONE }
105};
106
107///////////////////////////////////////////////////////////////////////////////
108// Constructors/destructor
109///////////////////////////////////////////////////////////////////////////////
110
111OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
112    mShader = NULL;
113    mColorFilter = NULL;
114    mHasShadow = false;
115    mHasDrawFilter = false;
116
117    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
118
119    mFirstSnapshot = new Snapshot;
120}
121
122OpenGLRenderer::~OpenGLRenderer() {
123    // The context has already been destroyed at this point, do not call
124    // GL APIs. All GL state should be kept in Caches.h
125}
126
127///////////////////////////////////////////////////////////////////////////////
128// Debug
129///////////////////////////////////////////////////////////////////////////////
130
131void OpenGLRenderer::startMark(const char* name) const {
132    mCaches.startMark(0, name);
133}
134
135void OpenGLRenderer::endMark() const {
136    mCaches.endMark();
137}
138
139///////////////////////////////////////////////////////////////////////////////
140// Setup
141///////////////////////////////////////////////////////////////////////////////
142
143uint32_t OpenGLRenderer::getStencilSize() {
144    return STENCIL_BUFFER_SIZE;
145}
146
147void OpenGLRenderer::setViewport(int width, int height) {
148    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
149
150    mWidth = width;
151    mHeight = height;
152
153    mFirstSnapshot->height = height;
154    mFirstSnapshot->viewport.set(0, 0, width, height);
155
156    glDisable(GL_DITHER);
157    glEnable(GL_SCISSOR_TEST);
158    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
159
160    glEnableVertexAttribArray(Program::kBindingPosition);
161}
162
163void OpenGLRenderer::prepare(bool opaque) {
164    prepareDirty(0.0f, 0.0f, mWidth, mHeight, opaque);
165}
166
167void OpenGLRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
168    mCaches.clearGarbage();
169    mFunctors.clear();
170
171    mSnapshot = new Snapshot(mFirstSnapshot,
172            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
173    mSnapshot->fbo = getTargetFbo();
174    mSaveCount = 1;
175
176    glViewport(0, 0, mWidth, mHeight);
177    mCaches.setScissor(left, mSnapshot->height - bottom, right - left, bottom - top);
178
179    mSnapshot->setClip(left, top, right, bottom);
180    mDirtyClip = false;
181
182    if (!opaque) {
183        glClear(GL_COLOR_BUFFER_BIT);
184    }
185}
186
187void OpenGLRenderer::finish() {
188#if DEBUG_OPENGL
189    GLenum status = GL_NO_ERROR;
190    while ((status = glGetError()) != GL_NO_ERROR) {
191        ALOGD("GL error from OpenGLRenderer: 0x%x", status);
192        switch (status) {
193            case GL_OUT_OF_MEMORY:
194                ALOGE("  OpenGLRenderer is out of memory!");
195                break;
196        }
197    }
198#endif
199#if DEBUG_MEMORY_USAGE
200    mCaches.dumpMemoryUsage();
201#else
202    if (mCaches.getDebugLevel() & kDebugMemory) {
203        mCaches.dumpMemoryUsage();
204    }
205#endif
206}
207
208void OpenGLRenderer::interrupt() {
209    if (mCaches.currentProgram) {
210        if (mCaches.currentProgram->isInUse()) {
211            mCaches.currentProgram->remove();
212            mCaches.currentProgram = NULL;
213        }
214    }
215    mCaches.unbindMeshBuffer();
216    mCaches.unbindIndicesBuffer();
217    mCaches.resetVertexPointers();
218    mCaches.disbaleTexCoordsVertexArray();
219}
220
221void OpenGLRenderer::resume() {
222    sp<Snapshot> snapshot = (mSnapshot != NULL) ? mSnapshot : mFirstSnapshot;
223
224    glViewport(0, 0, snapshot->viewport.getWidth(), snapshot->viewport.getHeight());
225    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
226
227    glEnable(GL_SCISSOR_TEST);
228    mCaches.resetScissor();
229    dirtyClip();
230
231    mCaches.activeTexture(0);
232    glBindFramebuffer(GL_FRAMEBUFFER, snapshot->fbo);
233
234    mCaches.blend = true;
235    glEnable(GL_BLEND);
236    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
237    glBlendEquation(GL_FUNC_ADD);
238}
239
240status_t OpenGLRenderer::invokeFunctors(Rect& dirty) {
241    status_t result = DrawGlInfo::kStatusDone;
242
243    Vector<Functor*> functors(mFunctors);
244    mFunctors.clear();
245
246    DrawGlInfo info;
247    info.clipLeft = 0;
248    info.clipTop = 0;
249    info.clipRight = 0;
250    info.clipBottom = 0;
251    info.isLayer = false;
252    memset(info.transform, 0, sizeof(float) * 16);
253
254    size_t count = functors.size();
255    for (size_t i = 0; i < count; i++) {
256        Functor* f = functors.itemAt(i);
257        result |= (*f)(DrawGlInfo::kModeProcess, &info);
258
259        if (result != DrawGlInfo::kStatusDone) {
260            Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
261            dirty.unionWith(localDirty);
262
263            if (result == DrawGlInfo::kStatusInvoke) {
264                mFunctors.push(f);
265            }
266        }
267    }
268
269    return result;
270}
271
272status_t OpenGLRenderer::callDrawGLFunction(Functor* functor, Rect& dirty) {
273    interrupt();
274    if (mDirtyClip) {
275        setScissorFromClip();
276    }
277
278    Rect clip(*mSnapshot->clipRect);
279    clip.snapToPixelBoundaries();
280
281#if RENDER_LAYERS_AS_REGIONS
282    // Since we don't know what the functor will draw, let's dirty
283    // tne entire clip region
284    if (hasLayer()) {
285        dirtyLayerUnchecked(clip, getRegion());
286    }
287#endif
288
289    DrawGlInfo info;
290    info.clipLeft = clip.left;
291    info.clipTop = clip.top;
292    info.clipRight = clip.right;
293    info.clipBottom = clip.bottom;
294    info.isLayer = hasLayer();
295    getSnapshot()->transform->copyTo(&info.transform[0]);
296
297    status_t result = (*functor)(DrawGlInfo::kModeDraw, &info);
298
299    if (result != DrawGlInfo::kStatusDone) {
300        Rect localDirty(info.dirtyLeft, info.dirtyTop, info.dirtyRight, info.dirtyBottom);
301        dirty.unionWith(localDirty);
302
303        if (result == DrawGlInfo::kStatusInvoke) {
304            mFunctors.push(functor);
305        }
306    }
307
308    resume();
309    return result;
310}
311
312///////////////////////////////////////////////////////////////////////////////
313// State management
314///////////////////////////////////////////////////////////////////////////////
315
316int OpenGLRenderer::getSaveCount() const {
317    return mSaveCount;
318}
319
320int OpenGLRenderer::save(int flags) {
321    return saveSnapshot(flags);
322}
323
324void OpenGLRenderer::restore() {
325    if (mSaveCount > 1) {
326        restoreSnapshot();
327    }
328}
329
330void OpenGLRenderer::restoreToCount(int saveCount) {
331    if (saveCount < 1) saveCount = 1;
332
333    while (mSaveCount > saveCount) {
334        restoreSnapshot();
335    }
336}
337
338int OpenGLRenderer::saveSnapshot(int flags) {
339    mSnapshot = new Snapshot(mSnapshot, flags);
340    return mSaveCount++;
341}
342
343bool OpenGLRenderer::restoreSnapshot() {
344    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
345    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
346    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
347
348    sp<Snapshot> current = mSnapshot;
349    sp<Snapshot> previous = mSnapshot->previous;
350
351    if (restoreOrtho) {
352        Rect& r = previous->viewport;
353        glViewport(r.left, r.top, r.right, r.bottom);
354        mOrthoMatrix.load(current->orthoMatrix);
355    }
356
357    mSaveCount--;
358    mSnapshot = previous;
359
360    if (restoreClip) {
361        dirtyClip();
362    }
363
364    if (restoreLayer) {
365        composeLayer(current, previous);
366    }
367
368    return restoreClip;
369}
370
371///////////////////////////////////////////////////////////////////////////////
372// Layers
373///////////////////////////////////////////////////////////////////////////////
374
375int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
376        SkPaint* p, int flags) {
377    const GLuint previousFbo = mSnapshot->fbo;
378    const int count = saveSnapshot(flags);
379
380    if (!mSnapshot->isIgnored()) {
381        int alpha = 255;
382        SkXfermode::Mode mode;
383
384        if (p) {
385            alpha = p->getAlpha();
386            if (!mCaches.extensions.hasFramebufferFetch()) {
387                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
388                if (!isMode) {
389                    // Assume SRC_OVER
390                    mode = SkXfermode::kSrcOver_Mode;
391                }
392            } else {
393                mode = getXfermode(p->getXfermode());
394            }
395        } else {
396            mode = SkXfermode::kSrcOver_Mode;
397        }
398
399        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
400    }
401
402    return count;
403}
404
405int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
406        int alpha, int flags) {
407    if (alpha >= 255 - ALPHA_THRESHOLD) {
408        return saveLayer(left, top, right, bottom, NULL, flags);
409    } else {
410        SkPaint paint;
411        paint.setAlpha(alpha);
412        return saveLayer(left, top, right, bottom, &paint, flags);
413    }
414}
415
416/**
417 * Layers are viewed by Skia are slightly different than layers in image editing
418 * programs (for instance.) When a layer is created, previously created layers
419 * and the frame buffer still receive every drawing command. For instance, if a
420 * layer is created and a shape intersecting the bounds of the layers and the
421 * framebuffer is draw, the shape will be drawn on both (unless the layer was
422 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
423 *
424 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
425 * texture. Unfortunately, this is inefficient as it requires every primitive to
426 * be drawn n + 1 times, where n is the number of active layers. In practice this
427 * means, for every primitive:
428 *   - Switch active frame buffer
429 *   - Change viewport, clip and projection matrix
430 *   - Issue the drawing
431 *
432 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
433 * To avoid this, layers are implemented in a different way here, at least in the
434 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
435 * is set. When this flag is set we can redirect all drawing operations into a
436 * single FBO.
437 *
438 * This implementation relies on the frame buffer being at least RGBA 8888. When
439 * a layer is created, only a texture is created, not an FBO. The content of the
440 * frame buffer contained within the layer's bounds is copied into this texture
441 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
442 * buffer and drawing continues as normal. This technique therefore treats the
443 * frame buffer as a scratch buffer for the layers.
444 *
445 * To compose the layers back onto the frame buffer, each layer texture
446 * (containing the original frame buffer data) is drawn as a simple quad over
447 * the frame buffer. The trick is that the quad is set as the composition
448 * destination in the blending equation, and the frame buffer becomes the source
449 * of the composition.
450 *
451 * Drawing layers with an alpha value requires an extra step before composition.
452 * An empty quad is drawn over the layer's region in the frame buffer. This quad
453 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
454 * quad is used to multiply the colors in the frame buffer. This is achieved by
455 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
456 * GL_ZERO, GL_SRC_ALPHA.
457 *
458 * Because glCopyTexImage2D() can be slow, an alternative implementation might
459 * be use to draw a single clipped layer. The implementation described above
460 * is correct in every case.
461 *
462 * (1) The frame buffer is actually not cleared right away. To allow the GPU
463 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
464 *     buffer is left untouched until the first drawing operation. Only when
465 *     something actually gets drawn are the layers regions cleared.
466 */
467bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
468        float right, float bottom, int alpha, SkXfermode::Mode mode,
469        int flags, GLuint previousFbo) {
470    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
471    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
472
473    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
474
475    // Window coordinates of the layer
476    Rect bounds(left, top, right, bottom);
477    if (!fboLayer) {
478        mSnapshot->transform->mapRect(bounds);
479
480        // Layers only make sense if they are in the framebuffer's bounds
481        if (bounds.intersect(*snapshot->clipRect)) {
482            // We cannot work with sub-pixels in this case
483            bounds.snapToPixelBoundaries();
484
485            // When the layer is not an FBO, we may use glCopyTexImage so we
486            // need to make sure the layer does not extend outside the bounds
487            // of the framebuffer
488            if (!bounds.intersect(snapshot->previous->viewport)) {
489                bounds.setEmpty();
490            }
491        } else {
492            bounds.setEmpty();
493        }
494    }
495
496    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
497            bounds.getHeight() > mCaches.maxTextureSize) {
498        snapshot->empty = fboLayer;
499    } else {
500        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
501    }
502
503    // Bail out if we won't draw in this snapshot
504    if (snapshot->invisible || snapshot->empty) {
505        return false;
506    }
507
508    mCaches.activeTexture(0);
509    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
510    if (!layer) {
511        return false;
512    }
513
514    layer->setAlpha(alpha, mode);
515    layer->layer.set(bounds);
516    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->getHeight()),
517            bounds.getWidth() / float(layer->getWidth()), 0.0f);
518    layer->setColorFilter(mColorFilter);
519
520    // Save the layer in the snapshot
521    snapshot->flags |= Snapshot::kFlagIsLayer;
522    snapshot->layer = layer;
523
524    if (fboLayer) {
525        return createFboLayer(layer, bounds, snapshot, previousFbo);
526    } else {
527        // Copy the framebuffer into the layer
528        layer->bindTexture();
529        if (!bounds.isEmpty()) {
530            if (layer->isEmpty()) {
531                glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
532                        bounds.left, snapshot->height - bounds.bottom,
533                        layer->getWidth(), layer->getHeight(), 0);
534                layer->setEmpty(false);
535            } else {
536                glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
537                        snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
538            }
539
540            // Enqueue the buffer coordinates to clear the corresponding region later
541            mLayers.push(new Rect(bounds));
542        }
543    }
544
545    return true;
546}
547
548bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
549        GLuint previousFbo) {
550    layer->setFbo(mCaches.fboCache.get());
551
552#if RENDER_LAYERS_AS_REGIONS
553    snapshot->region = &snapshot->layer->region;
554    snapshot->flags |= Snapshot::kFlagFboTarget;
555#endif
556
557    Rect clip(bounds);
558    snapshot->transform->mapRect(clip);
559    clip.intersect(*snapshot->clipRect);
560    clip.snapToPixelBoundaries();
561    clip.intersect(snapshot->previous->viewport);
562
563    mat4 inverse;
564    inverse.loadInverse(*mSnapshot->transform);
565
566    inverse.mapRect(clip);
567    clip.snapToPixelBoundaries();
568    clip.intersect(bounds);
569    clip.translate(-bounds.left, -bounds.top);
570
571    snapshot->flags |= Snapshot::kFlagIsFboLayer;
572    snapshot->fbo = layer->getFbo();
573    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
574    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
575    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
576    snapshot->height = bounds.getHeight();
577    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
578    snapshot->orthoMatrix.load(mOrthoMatrix);
579
580    // Bind texture to FBO
581    glBindFramebuffer(GL_FRAMEBUFFER, layer->getFbo());
582    layer->bindTexture();
583
584    // Initialize the texture if needed
585    if (layer->isEmpty()) {
586        layer->allocateTexture(GL_RGBA, GL_UNSIGNED_BYTE);
587        layer->setEmpty(false);
588    }
589
590    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
591            layer->getTexture(), 0);
592
593#if DEBUG_LAYERS_AS_REGIONS
594    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
595    if (status != GL_FRAMEBUFFER_COMPLETE) {
596        ALOGE("Framebuffer incomplete (GL error code 0x%x)", status);
597
598        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
599        layer->deleteTexture();
600        mCaches.fboCache.put(layer->getFbo());
601
602        delete layer;
603
604        return false;
605    }
606#endif
607
608    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
609    mCaches.setScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
610            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
611    glClear(GL_COLOR_BUFFER_BIT);
612
613    dirtyClip();
614
615    // Change the ortho projection
616    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
617    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
618
619    return true;
620}
621
622/**
623 * Read the documentation of createLayer() before doing anything in this method.
624 */
625void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
626    if (!current->layer) {
627        ALOGE("Attempting to compose a layer that does not exist");
628        return;
629    }
630
631    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
632
633    if (fboLayer) {
634        // Unbind current FBO and restore previous one
635        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
636    }
637
638    Layer* layer = current->layer;
639    const Rect& rect = layer->layer;
640
641    if (!fboLayer && layer->getAlpha() < 255) {
642        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
643                layer->getAlpha() << 24, SkXfermode::kDstIn_Mode, true);
644        // Required below, composeLayerRect() will divide by 255
645        layer->setAlpha(255);
646    }
647
648    mCaches.unbindMeshBuffer();
649
650    mCaches.activeTexture(0);
651
652    // When the layer is stored in an FBO, we can save a bit of fillrate by
653    // drawing only the dirty region
654    if (fboLayer) {
655        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
656        if (layer->getColorFilter()) {
657            setupColorFilter(layer->getColorFilter());
658        }
659        composeLayerRegion(layer, rect);
660        if (layer->getColorFilter()) {
661            resetColorFilter();
662        }
663    } else if (!rect.isEmpty()) {
664        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
665        composeLayerRect(layer, rect, true);
666    }
667
668    if (fboLayer) {
669        // Note: No need to use glDiscardFramebufferEXT() since we never
670        //       create/compose layers that are not on screen with this
671        //       code path
672        // See LayerRenderer::destroyLayer(Layer*)
673
674        // Detach the texture from the FBO
675        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
676        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
677        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
678
679        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
680        mCaches.fboCache.put(current->fbo);
681        layer->setFbo(0);
682    }
683
684    dirtyClip();
685
686    // Failing to add the layer to the cache should happen only if the layer is too large
687    if (!mCaches.layerCache.put(layer)) {
688        LAYER_LOGD("Deleting layer");
689        layer->deleteTexture();
690        delete layer;
691    }
692}
693
694void OpenGLRenderer::drawTextureLayer(Layer* layer, const Rect& rect) {
695    float alpha = layer->getAlpha() / 255.0f;
696
697    mat4& transform = layer->getTransform();
698    if (!transform.isIdentity()) {
699        save(0);
700        mSnapshot->transform->multiply(transform);
701    }
702
703    setupDraw();
704    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
705        setupDrawWithTexture();
706    } else {
707        setupDrawWithExternalTexture();
708    }
709    setupDrawTextureTransform();
710    setupDrawColor(alpha, alpha, alpha, alpha);
711    setupDrawColorFilter();
712    setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode());
713    setupDrawProgram();
714    setupDrawPureColorUniforms();
715    setupDrawColorFilterUniforms();
716    if (layer->getRenderTarget() == GL_TEXTURE_2D) {
717        setupDrawTexture(layer->getTexture());
718    } else {
719        setupDrawExternalTexture(layer->getTexture());
720    }
721    if (mSnapshot->transform->isPureTranslate() &&
722            layer->getWidth() == (uint32_t) rect.getWidth() &&
723            layer->getHeight() == (uint32_t) rect.getHeight()) {
724        const float x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
725        const float y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
726
727        layer->setFilter(GL_NEAREST);
728        setupDrawModelView(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
729    } else {
730        layer->setFilter(GL_LINEAR);
731        setupDrawModelView(rect.left, rect.top, rect.right, rect.bottom);
732    }
733    setupDrawTextureTransformUniforms(layer->getTexTransform());
734    setupDrawMesh(&mMeshVertices[0].position[0], &mMeshVertices[0].texture[0]);
735
736    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
737
738    finishDrawTexture();
739
740    if (!transform.isIdentity()) {
741        restore();
742    }
743}
744
745void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
746    if (!layer->isTextureLayer()) {
747        const Rect& texCoords = layer->texCoords;
748        resetDrawTextureTexCoords(texCoords.left, texCoords.top,
749                texCoords.right, texCoords.bottom);
750
751        float x = rect.left;
752        float y = rect.top;
753        bool simpleTransform = mSnapshot->transform->isPureTranslate() &&
754                layer->getWidth() == (uint32_t) rect.getWidth() &&
755                layer->getHeight() == (uint32_t) rect.getHeight();
756
757        if (simpleTransform) {
758            // When we're swapping, the layer is already in screen coordinates
759            if (!swap) {
760                x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
761                y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
762            }
763
764            layer->setFilter(GL_NEAREST, true);
765        } else {
766            layer->setFilter(GL_LINEAR, true);
767        }
768
769        drawTextureMesh(x, y, x + rect.getWidth(), y + rect.getHeight(),
770                layer->getTexture(), layer->getAlpha() / 255.0f,
771                layer->getMode(), layer->isBlend(),
772                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
773                GL_TRIANGLE_STRIP, gMeshCount, swap, swap || simpleTransform);
774
775        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
776    } else {
777        resetDrawTextureTexCoords(0.0f, 1.0f, 1.0f, 0.0f);
778        drawTextureLayer(layer, rect);
779        resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
780    }
781}
782
783void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
784#if RENDER_LAYERS_AS_REGIONS
785    if (layer->region.isRect()) {
786        layer->setRegionAsRect();
787
788        composeLayerRect(layer, layer->regionRect);
789
790        layer->region.clear();
791        return;
792    }
793
794    // TODO: See LayerRenderer.cpp::generateMesh() for important
795    //       information about this implementation
796    if (CC_LIKELY(!layer->region.isEmpty())) {
797        size_t count;
798        const android::Rect* rects = layer->region.getArray(&count);
799
800        const float alpha = layer->getAlpha() / 255.0f;
801        const float texX = 1.0f / float(layer->getWidth());
802        const float texY = 1.0f / float(layer->getHeight());
803        const float height = rect.getHeight();
804
805        TextureVertex* mesh = mCaches.getRegionMesh();
806        GLsizei numQuads = 0;
807
808        setupDraw();
809        setupDrawWithTexture();
810        setupDrawColor(alpha, alpha, alpha, alpha);
811        setupDrawColorFilter();
812        setupDrawBlending(layer->isBlend() || alpha < 1.0f, layer->getMode(), false);
813        setupDrawProgram();
814        setupDrawDirtyRegionsDisabled();
815        setupDrawPureColorUniforms();
816        setupDrawColorFilterUniforms();
817        setupDrawTexture(layer->getTexture());
818        if (mSnapshot->transform->isPureTranslate()) {
819            const float x = (int) floorf(rect.left + mSnapshot->transform->getTranslateX() + 0.5f);
820            const float y = (int) floorf(rect.top + mSnapshot->transform->getTranslateY() + 0.5f);
821
822            layer->setFilter(GL_NEAREST);
823            setupDrawModelViewTranslate(x, y, x + rect.getWidth(), y + rect.getHeight(), true);
824        } else {
825            layer->setFilter(GL_LINEAR);
826            setupDrawModelViewTranslate(rect.left, rect.top, rect.right, rect.bottom);
827        }
828        setupDrawMeshIndices(&mesh[0].position[0], &mesh[0].texture[0]);
829
830        for (size_t i = 0; i < count; i++) {
831            const android::Rect* r = &rects[i];
832
833            const float u1 = r->left * texX;
834            const float v1 = (height - r->top) * texY;
835            const float u2 = r->right * texX;
836            const float v2 = (height - r->bottom) * texY;
837
838            // TODO: Reject quads outside of the clip
839            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
840            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
841            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
842            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
843
844            numQuads++;
845
846            if (numQuads >= REGION_MESH_QUAD_COUNT) {
847                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
848                numQuads = 0;
849                mesh = mCaches.getRegionMesh();
850            }
851        }
852
853        if (numQuads > 0) {
854            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
855        }
856
857        finishDrawTexture();
858
859#if DEBUG_LAYERS_AS_REGIONS
860        drawRegionRects(layer->region);
861#endif
862
863        layer->region.clear();
864    }
865#else
866    composeLayerRect(layer, rect);
867#endif
868}
869
870void OpenGLRenderer::drawRegionRects(const Region& region) {
871#if DEBUG_LAYERS_AS_REGIONS
872    size_t count;
873    const android::Rect* rects = region.getArray(&count);
874
875    uint32_t colors[] = {
876            0x7fff0000, 0x7f00ff00,
877            0x7f0000ff, 0x7fff00ff,
878    };
879
880    int offset = 0;
881    int32_t top = rects[0].top;
882
883    for (size_t i = 0; i < count; i++) {
884        if (top != rects[i].top) {
885            offset ^= 0x2;
886            top = rects[i].top;
887        }
888
889        Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
890        drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
891                SkXfermode::kSrcOver_Mode);
892    }
893#endif
894}
895
896void OpenGLRenderer::dirtyLayer(const float left, const float top,
897        const float right, const float bottom, const mat4 transform) {
898#if RENDER_LAYERS_AS_REGIONS
899    if (hasLayer()) {
900        Rect bounds(left, top, right, bottom);
901        transform.mapRect(bounds);
902        dirtyLayerUnchecked(bounds, getRegion());
903    }
904#endif
905}
906
907void OpenGLRenderer::dirtyLayer(const float left, const float top,
908        const float right, const float bottom) {
909#if RENDER_LAYERS_AS_REGIONS
910    if (hasLayer()) {
911        Rect bounds(left, top, right, bottom);
912        dirtyLayerUnchecked(bounds, getRegion());
913    }
914#endif
915}
916
917void OpenGLRenderer::dirtyLayerUnchecked(Rect& bounds, Region* region) {
918#if RENDER_LAYERS_AS_REGIONS
919    if (bounds.intersect(*mSnapshot->clipRect)) {
920        bounds.snapToPixelBoundaries();
921        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
922        if (!dirty.isEmpty()) {
923            region->orSelf(dirty);
924        }
925    }
926#endif
927}
928
929void OpenGLRenderer::clearLayerRegions() {
930    const size_t count = mLayers.size();
931    if (count == 0) return;
932
933    if (!mSnapshot->isIgnored()) {
934        // Doing several glScissor/glClear here can negatively impact
935        // GPUs with a tiler architecture, instead we draw quads with
936        // the Clear blending mode
937
938        // The list contains bounds that have already been clipped
939        // against their initial clip rect, and the current clip
940        // is likely different so we need to disable clipping here
941        glDisable(GL_SCISSOR_TEST);
942
943        Vertex mesh[count * 6];
944        Vertex* vertex = mesh;
945
946        for (uint32_t i = 0; i < count; i++) {
947            Rect* bounds = mLayers.itemAt(i);
948
949            Vertex::set(vertex++, bounds->left, bounds->bottom);
950            Vertex::set(vertex++, bounds->left, bounds->top);
951            Vertex::set(vertex++, bounds->right, bounds->top);
952            Vertex::set(vertex++, bounds->left, bounds->bottom);
953            Vertex::set(vertex++, bounds->right, bounds->top);
954            Vertex::set(vertex++, bounds->right, bounds->bottom);
955
956            delete bounds;
957        }
958
959        setupDraw(false);
960        setupDrawColor(0.0f, 0.0f, 0.0f, 1.0f);
961        setupDrawBlending(true, SkXfermode::kClear_Mode);
962        setupDrawProgram();
963        setupDrawPureColorUniforms();
964        setupDrawModelViewTranslate(0.0f, 0.0f, 0.0f, 0.0f, true);
965        setupDrawVertices(&mesh[0].position[0]);
966
967        glDrawArrays(GL_TRIANGLES, 0, count * 6);
968
969        glEnable(GL_SCISSOR_TEST);
970    } else {
971        for (uint32_t i = 0; i < count; i++) {
972            delete mLayers.itemAt(i);
973        }
974    }
975
976    mLayers.clear();
977}
978
979///////////////////////////////////////////////////////////////////////////////
980// Transforms
981///////////////////////////////////////////////////////////////////////////////
982
983void OpenGLRenderer::translate(float dx, float dy) {
984    mSnapshot->transform->translate(dx, dy, 0.0f);
985}
986
987void OpenGLRenderer::rotate(float degrees) {
988    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
989}
990
991void OpenGLRenderer::scale(float sx, float sy) {
992    mSnapshot->transform->scale(sx, sy, 1.0f);
993}
994
995void OpenGLRenderer::skew(float sx, float sy) {
996    mSnapshot->transform->skew(sx, sy);
997}
998
999void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
1000    if (matrix) {
1001        mSnapshot->transform->load(*matrix);
1002    } else {
1003        mSnapshot->transform->loadIdentity();
1004    }
1005}
1006
1007void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
1008    mSnapshot->transform->copyTo(*matrix);
1009}
1010
1011void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
1012    SkMatrix transform;
1013    mSnapshot->transform->copyTo(transform);
1014    transform.preConcat(*matrix);
1015    mSnapshot->transform->load(transform);
1016}
1017
1018///////////////////////////////////////////////////////////////////////////////
1019// Clipping
1020///////////////////////////////////////////////////////////////////////////////
1021
1022void OpenGLRenderer::setScissorFromClip() {
1023    Rect clip(*mSnapshot->clipRect);
1024    clip.snapToPixelBoundaries();
1025
1026    mCaches.setScissor(clip.left, mSnapshot->height - clip.bottom,
1027            clip.getWidth(), clip.getHeight());
1028
1029    mDirtyClip = false;
1030}
1031
1032const Rect& OpenGLRenderer::getClipBounds() {
1033    return mSnapshot->getLocalClip();
1034}
1035
1036bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
1037    if (mSnapshot->isIgnored()) {
1038        return true;
1039    }
1040
1041    Rect r(left, top, right, bottom);
1042    mSnapshot->transform->mapRect(r);
1043    r.snapToPixelBoundaries();
1044
1045    Rect clipRect(*mSnapshot->clipRect);
1046    clipRect.snapToPixelBoundaries();
1047
1048    return !clipRect.intersects(r);
1049}
1050
1051bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
1052    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
1053    if (clipped) {
1054        dirtyClip();
1055    }
1056    return !mSnapshot->clipRect->isEmpty();
1057}
1058
1059///////////////////////////////////////////////////////////////////////////////
1060// Drawing commands
1061///////////////////////////////////////////////////////////////////////////////
1062
1063void OpenGLRenderer::setupDraw(bool clear) {
1064    if (clear) clearLayerRegions();
1065    if (mDirtyClip) {
1066        setScissorFromClip();
1067    }
1068    mDescription.reset();
1069    mSetShaderColor = false;
1070    mColorSet = false;
1071    mColorA = mColorR = mColorG = mColorB = 0.0f;
1072    mTextureUnit = 0;
1073    mTrackDirtyRegions = true;
1074}
1075
1076void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
1077    mDescription.hasTexture = true;
1078    mDescription.hasAlpha8Texture = isAlpha8;
1079}
1080
1081void OpenGLRenderer::setupDrawWithExternalTexture() {
1082    mDescription.hasExternalTexture = true;
1083}
1084
1085void OpenGLRenderer::setupDrawNoTexture() {
1086    mCaches.disbaleTexCoordsVertexArray();
1087}
1088
1089void OpenGLRenderer::setupDrawAALine() {
1090    mDescription.isAA = true;
1091}
1092
1093void OpenGLRenderer::setupDrawPoint(float pointSize) {
1094    mDescription.isPoint = true;
1095    mDescription.pointSize = pointSize;
1096}
1097
1098void OpenGLRenderer::setupDrawColor(int color) {
1099    setupDrawColor(color, (color >> 24) & 0xFF);
1100}
1101
1102void OpenGLRenderer::setupDrawColor(int color, int alpha) {
1103    mColorA = alpha / 255.0f;
1104    // Second divide of a by 255 is an optimization, allowing us to simply multiply
1105    // the rgb values by a instead of also dividing by 255
1106    const float a = mColorA / 255.0f;
1107    mColorR = a * ((color >> 16) & 0xFF);
1108    mColorG = a * ((color >>  8) & 0xFF);
1109    mColorB = a * ((color      ) & 0xFF);
1110    mColorSet = true;
1111    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
1112}
1113
1114void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
1115    mColorA = alpha / 255.0f;
1116    // Double-divide of a by 255 is an optimization, allowing us to simply multiply
1117    // the rgb values by a instead of also dividing by 255
1118    const float a = mColorA / 255.0f;
1119    mColorR = a * ((color >> 16) & 0xFF);
1120    mColorG = a * ((color >>  8) & 0xFF);
1121    mColorB = a * ((color      ) & 0xFF);
1122    mColorSet = true;
1123    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
1124}
1125
1126void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
1127    mColorA = a;
1128    mColorR = r;
1129    mColorG = g;
1130    mColorB = b;
1131    mColorSet = true;
1132    mSetShaderColor = mDescription.setColor(r, g, b, a);
1133}
1134
1135void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
1136    mColorA = a;
1137    mColorR = r;
1138    mColorG = g;
1139    mColorB = b;
1140    mColorSet = true;
1141    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
1142}
1143
1144void OpenGLRenderer::setupDrawShader() {
1145    if (mShader) {
1146        mShader->describe(mDescription, mCaches.extensions);
1147    }
1148}
1149
1150void OpenGLRenderer::setupDrawColorFilter() {
1151    if (mColorFilter) {
1152        mColorFilter->describe(mDescription, mCaches.extensions);
1153    }
1154}
1155
1156void OpenGLRenderer::accountForClear(SkXfermode::Mode mode) {
1157    if (mColorSet && mode == SkXfermode::kClear_Mode) {
1158        mColorA = 1.0f;
1159        mColorR = mColorG = mColorB = 0.0f;
1160        mSetShaderColor = mDescription.modulate = true;
1161    }
1162}
1163
1164void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
1165    // When the blending mode is kClear_Mode, we need to use a modulate color
1166    // argb=1,0,0,0
1167    accountForClear(mode);
1168    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
1169            mDescription, swapSrcDst);
1170}
1171
1172void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
1173    // When the blending mode is kClear_Mode, we need to use a modulate color
1174    // argb=1,0,0,0
1175    accountForClear(mode);
1176    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
1177            mDescription, swapSrcDst);
1178}
1179
1180void OpenGLRenderer::setupDrawProgram() {
1181    useProgram(mCaches.programCache.get(mDescription));
1182}
1183
1184void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
1185    mTrackDirtyRegions = false;
1186}
1187
1188void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
1189        bool ignoreTransform) {
1190    mModelView.loadTranslate(left, top, 0.0f);
1191    if (!ignoreTransform) {
1192        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
1193        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1194    } else {
1195        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
1196        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
1197    }
1198}
1199
1200void OpenGLRenderer::setupDrawModelViewIdentity(bool offset) {
1201    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform, offset);
1202}
1203
1204void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
1205        bool ignoreTransform, bool ignoreModelView) {
1206    if (!ignoreModelView) {
1207        mModelView.loadTranslate(left, top, 0.0f);
1208        mModelView.scale(right - left, bottom - top, 1.0f);
1209    } else {
1210        mModelView.loadIdentity();
1211    }
1212    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
1213    if (!ignoreTransform) {
1214        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
1215        if (mTrackDirtyRegions && dirty) {
1216            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1217        }
1218    } else {
1219        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
1220        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
1221    }
1222}
1223
1224void OpenGLRenderer::setupDrawPointUniforms() {
1225    int slot = mCaches.currentProgram->getUniform("pointSize");
1226    glUniform1f(slot, mDescription.pointSize);
1227}
1228
1229void OpenGLRenderer::setupDrawColorUniforms() {
1230    if ((mColorSet && !mShader) || (mShader && mSetShaderColor)) {
1231        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1232    }
1233}
1234
1235void OpenGLRenderer::setupDrawPureColorUniforms() {
1236    if (mSetShaderColor) {
1237        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
1238    }
1239}
1240
1241void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
1242    if (mShader) {
1243        if (ignoreTransform) {
1244            mModelView.loadInverse(*mSnapshot->transform);
1245        }
1246        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
1247    }
1248}
1249
1250void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
1251    if (mShader) {
1252        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
1253    }
1254}
1255
1256void OpenGLRenderer::setupDrawColorFilterUniforms() {
1257    if (mColorFilter) {
1258        mColorFilter->setupProgram(mCaches.currentProgram);
1259    }
1260}
1261
1262void OpenGLRenderer::setupDrawSimpleMesh() {
1263    bool force = mCaches.bindMeshBuffer();
1264    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, 0);
1265    mCaches.unbindIndicesBuffer();
1266}
1267
1268void OpenGLRenderer::setupDrawTexture(GLuint texture) {
1269    bindTexture(texture);
1270    mTextureUnit++;
1271    mCaches.enableTexCoordsVertexArray();
1272}
1273
1274void OpenGLRenderer::setupDrawExternalTexture(GLuint texture) {
1275    bindExternalTexture(texture);
1276    mTextureUnit++;
1277    mCaches.enableTexCoordsVertexArray();
1278}
1279
1280void OpenGLRenderer::setupDrawTextureTransform() {
1281    mDescription.hasTextureTransform = true;
1282}
1283
1284void OpenGLRenderer::setupDrawTextureTransformUniforms(mat4& transform) {
1285    glUniformMatrix4fv(mCaches.currentProgram->getUniform("mainTextureTransform"), 1,
1286            GL_FALSE, &transform.data[0]);
1287}
1288
1289void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1290    bool force = false;
1291    if (!vertices) {
1292        force = mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1293    } else {
1294        force = mCaches.unbindMeshBuffer();
1295    }
1296
1297    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, vertices);
1298    if (mCaches.currentProgram->texCoords >= 0) {
1299        mCaches.bindTexCoordsVertexPointer(force, mCaches.currentProgram->texCoords, texCoords);
1300    }
1301
1302    mCaches.unbindIndicesBuffer();
1303}
1304
1305void OpenGLRenderer::setupDrawMeshIndices(GLvoid* vertices, GLvoid* texCoords) {
1306    bool force = mCaches.unbindMeshBuffer();
1307    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position, vertices);
1308    if (mCaches.currentProgram->texCoords >= 0) {
1309        mCaches.bindTexCoordsVertexPointer(force, mCaches.currentProgram->texCoords, texCoords);
1310    }
1311}
1312
1313void OpenGLRenderer::setupDrawVertices(GLvoid* vertices) {
1314    bool force = mCaches.unbindMeshBuffer();
1315    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position,
1316            vertices, gVertexStride);
1317    mCaches.unbindIndicesBuffer();
1318}
1319
1320/**
1321 * Sets up the shader to draw an AA line. We draw AA lines with quads, where there is an
1322 * outer boundary that fades out to 0. The variables set in the shader define the proportion of
1323 * the width and length of the primitive occupied by the AA region. The vtxWidth and vtxLength
1324 * attributes (one per vertex) are values from zero to one that tells the fragment
1325 * shader where the fragment is in relation to the line width/length overall; these values are
1326 * then used to compute the proper color, based on whether the fragment lies in the fading AA
1327 * region of the line.
1328 * Note that we only pass down the width values in this setup function. The length coordinates
1329 * are set up for each individual segment.
1330 */
1331void OpenGLRenderer::setupDrawAALine(GLvoid* vertices, GLvoid* widthCoords,
1332        GLvoid* lengthCoords, float boundaryWidthProportion) {
1333    bool force = mCaches.unbindMeshBuffer();
1334    mCaches.bindPositionVertexPointer(force, mCaches.currentProgram->position,
1335            vertices, gAAVertexStride);
1336    mCaches.resetTexCoordsVertexPointer();
1337    mCaches.unbindIndicesBuffer();
1338
1339    int widthSlot = mCaches.currentProgram->getAttrib("vtxWidth");
1340    glEnableVertexAttribArray(widthSlot);
1341    glVertexAttribPointer(widthSlot, 1, GL_FLOAT, GL_FALSE, gAAVertexStride, widthCoords);
1342
1343    int lengthSlot = mCaches.currentProgram->getAttrib("vtxLength");
1344    glEnableVertexAttribArray(lengthSlot);
1345    glVertexAttribPointer(lengthSlot, 1, GL_FLOAT, GL_FALSE, gAAVertexStride, lengthCoords);
1346
1347    int boundaryWidthSlot = mCaches.currentProgram->getUniform("boundaryWidth");
1348    glUniform1f(boundaryWidthSlot, boundaryWidthProportion);
1349
1350    // Setting the inverse value saves computations per-fragment in the shader
1351    int inverseBoundaryWidthSlot = mCaches.currentProgram->getUniform("inverseBoundaryWidth");
1352    glUniform1f(inverseBoundaryWidthSlot, (1 / boundaryWidthProportion));
1353}
1354
1355void OpenGLRenderer::finishDrawTexture() {
1356}
1357
1358///////////////////////////////////////////////////////////////////////////////
1359// Drawing
1360///////////////////////////////////////////////////////////////////////////////
1361
1362status_t OpenGLRenderer::drawDisplayList(DisplayList* displayList, uint32_t width, uint32_t height,
1363        Rect& dirty, int32_t flags, uint32_t level) {
1364
1365    if (!USE_DISPLAY_LIST_PROPERTIES && quickReject(0, 0, width, height)) {
1366        return false;
1367    }
1368
1369    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1370    // will be performed by the display list itself
1371    if (displayList && displayList->isRenderable()) {
1372        return displayList->replay(*this, width, height, dirty, flags, level);
1373    }
1374
1375    return DrawGlInfo::kStatusDone;
1376}
1377
1378void OpenGLRenderer::outputDisplayList(DisplayList* displayList, uint32_t level) {
1379    if (displayList) {
1380        displayList->output(*this, level);
1381    }
1382}
1383
1384void OpenGLRenderer::drawAlphaBitmap(Texture* texture, float left, float top, SkPaint* paint) {
1385    int alpha;
1386    SkXfermode::Mode mode;
1387    getAlphaAndMode(paint, &alpha, &mode);
1388
1389    float x = left;
1390    float y = top;
1391
1392    GLenum filter = GL_LINEAR;
1393    bool ignoreTransform = false;
1394    if (mSnapshot->transform->isPureTranslate()) {
1395        x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1396        y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1397        ignoreTransform = true;
1398        filter = GL_NEAREST;
1399    } else {
1400        filter = FILTER(paint);
1401    }
1402
1403    setupDraw();
1404    setupDrawWithTexture(true);
1405    if (paint) {
1406        setupDrawAlpha8Color(paint->getColor(), alpha);
1407    }
1408    setupDrawColorFilter();
1409    setupDrawShader();
1410    setupDrawBlending(true, mode);
1411    setupDrawProgram();
1412    setupDrawModelView(x, y, x + texture->width, y + texture->height, ignoreTransform);
1413
1414    setupDrawTexture(texture->id);
1415    texture->setWrap(GL_CLAMP_TO_EDGE);
1416    texture->setFilter(filter);
1417
1418    setupDrawPureColorUniforms();
1419    setupDrawColorFilterUniforms();
1420    setupDrawShaderUniforms();
1421    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1422
1423    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1424
1425    finishDrawTexture();
1426}
1427
1428void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1429    const float right = left + bitmap->width();
1430    const float bottom = top + bitmap->height();
1431
1432    if (quickReject(left, top, right, bottom)) {
1433        return;
1434    }
1435
1436    mCaches.activeTexture(0);
1437    Texture* texture = mCaches.textureCache.get(bitmap);
1438    if (!texture) return;
1439    const AutoTexture autoCleanup(texture);
1440
1441    if (CC_UNLIKELY(bitmap->getConfig() == SkBitmap::kA8_Config)) {
1442        drawAlphaBitmap(texture, left, top, paint);
1443    } else {
1444        drawTextureRect(left, top, right, bottom, texture, paint);
1445    }
1446}
1447
1448void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1449    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1450    const mat4 transform(*matrix);
1451    transform.mapRect(r);
1452
1453    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1454        return;
1455    }
1456
1457    mCaches.activeTexture(0);
1458    Texture* texture = mCaches.textureCache.get(bitmap);
1459    if (!texture) return;
1460    const AutoTexture autoCleanup(texture);
1461
1462    // This could be done in a cheaper way, all we need is pass the matrix
1463    // to the vertex shader. The save/restore is a bit overkill.
1464    save(SkCanvas::kMatrix_SaveFlag);
1465    concatMatrix(matrix);
1466    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1467    restore();
1468}
1469
1470void OpenGLRenderer::drawBitmapMesh(SkBitmap* bitmap, int meshWidth, int meshHeight,
1471        float* vertices, int* colors, SkPaint* paint) {
1472    // TODO: Do a quickReject
1473    if (!vertices || mSnapshot->isIgnored()) {
1474        return;
1475    }
1476
1477    mCaches.activeTexture(0);
1478    Texture* texture = mCaches.textureCache.get(bitmap);
1479    if (!texture) return;
1480    const AutoTexture autoCleanup(texture);
1481
1482    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1483    texture->setFilter(FILTER(paint), true);
1484
1485    int alpha;
1486    SkXfermode::Mode mode;
1487    getAlphaAndMode(paint, &alpha, &mode);
1488
1489    const uint32_t count = meshWidth * meshHeight * 6;
1490
1491    float left = FLT_MAX;
1492    float top = FLT_MAX;
1493    float right = FLT_MIN;
1494    float bottom = FLT_MIN;
1495
1496#if RENDER_LAYERS_AS_REGIONS
1497    const bool hasActiveLayer = hasLayer();
1498#else
1499    const bool hasActiveLayer = false;
1500#endif
1501
1502    // TODO: Support the colors array
1503    TextureVertex mesh[count];
1504    TextureVertex* vertex = mesh;
1505    for (int32_t y = 0; y < meshHeight; y++) {
1506        for (int32_t x = 0; x < meshWidth; x++) {
1507            uint32_t i = (y * (meshWidth + 1) + x) * 2;
1508
1509            float u1 = float(x) / meshWidth;
1510            float u2 = float(x + 1) / meshWidth;
1511            float v1 = float(y) / meshHeight;
1512            float v2 = float(y + 1) / meshHeight;
1513
1514            int ax = i + (meshWidth + 1) * 2;
1515            int ay = ax + 1;
1516            int bx = i;
1517            int by = bx + 1;
1518            int cx = i + 2;
1519            int cy = cx + 1;
1520            int dx = i + (meshWidth + 1) * 2 + 2;
1521            int dy = dx + 1;
1522
1523            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1524            TextureVertex::set(vertex++, vertices[bx], vertices[by], u1, v1);
1525            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1526
1527            TextureVertex::set(vertex++, vertices[ax], vertices[ay], u1, v2);
1528            TextureVertex::set(vertex++, vertices[cx], vertices[cy], u2, v1);
1529            TextureVertex::set(vertex++, vertices[dx], vertices[dy], u2, v2);
1530
1531#if RENDER_LAYERS_AS_REGIONS
1532            if (hasActiveLayer) {
1533                // TODO: This could be optimized to avoid unnecessary ops
1534                left = fminf(left, fminf(vertices[ax], fminf(vertices[bx], vertices[cx])));
1535                top = fminf(top, fminf(vertices[ay], fminf(vertices[by], vertices[cy])));
1536                right = fmaxf(right, fmaxf(vertices[ax], fmaxf(vertices[bx], vertices[cx])));
1537                bottom = fmaxf(bottom, fmaxf(vertices[ay], fmaxf(vertices[by], vertices[cy])));
1538            }
1539#endif
1540        }
1541    }
1542
1543#if RENDER_LAYERS_AS_REGIONS
1544    if (hasActiveLayer) {
1545        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1546    }
1547#endif
1548
1549    drawTextureMesh(0.0f, 0.0f, 1.0f, 1.0f, texture->id, alpha / 255.0f,
1550            mode, texture->blend, &mesh[0].position[0], &mesh[0].texture[0],
1551            GL_TRIANGLES, count, false, false, 0, false, false);
1552}
1553
1554void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1555         float srcLeft, float srcTop, float srcRight, float srcBottom,
1556         float dstLeft, float dstTop, float dstRight, float dstBottom,
1557         SkPaint* paint) {
1558    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1559        return;
1560    }
1561
1562    mCaches.activeTexture(0);
1563    Texture* texture = mCaches.textureCache.get(bitmap);
1564    if (!texture) return;
1565    const AutoTexture autoCleanup(texture);
1566
1567    const float width = texture->width;
1568    const float height = texture->height;
1569
1570    const float u1 = fmax(0.0f, srcLeft / width);
1571    const float v1 = fmax(0.0f, srcTop / height);
1572    const float u2 = fmin(1.0f, srcRight / width);
1573    const float v2 = fmin(1.0f, srcBottom / height);
1574
1575    mCaches.unbindMeshBuffer();
1576    resetDrawTextureTexCoords(u1, v1, u2, v2);
1577
1578    int alpha;
1579    SkXfermode::Mode mode;
1580    getAlphaAndMode(paint, &alpha, &mode);
1581
1582    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1583
1584    if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
1585        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1586        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1587
1588        GLenum filter = GL_NEAREST;
1589        // Enable linear filtering if the source rectangle is scaled
1590        if (srcRight - srcLeft != dstRight - dstLeft || srcBottom - srcTop != dstBottom - dstTop) {
1591            filter = FILTER(paint);
1592        }
1593
1594        texture->setFilter(filter, true);
1595        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1596                texture->id, alpha / 255.0f, mode, texture->blend,
1597                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1598                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1599    } else {
1600        texture->setFilter(FILTER(paint), true);
1601        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1602                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1603                GL_TRIANGLE_STRIP, gMeshCount);
1604    }
1605
1606    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1607}
1608
1609void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1610        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1611        float left, float top, float right, float bottom, SkPaint* paint) {
1612    if (quickReject(left, top, right, bottom)) {
1613        return;
1614    }
1615
1616    mCaches.activeTexture(0);
1617    Texture* texture = mCaches.textureCache.get(bitmap);
1618    if (!texture) return;
1619    const AutoTexture autoCleanup(texture);
1620    texture->setWrap(GL_CLAMP_TO_EDGE, true);
1621    texture->setFilter(GL_LINEAR, true);
1622
1623    int alpha;
1624    SkXfermode::Mode mode;
1625    getAlphaAndMode(paint, &alpha, &mode);
1626
1627    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1628            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1629
1630    if (CC_LIKELY(mesh && mesh->verticesCount > 0)) {
1631        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1632#if RENDER_LAYERS_AS_REGIONS
1633        // Mark the current layer dirty where we are going to draw the patch
1634        if (hasLayer() && mesh->hasEmptyQuads) {
1635            const float offsetX = left + mSnapshot->transform->getTranslateX();
1636            const float offsetY = top + mSnapshot->transform->getTranslateY();
1637            const size_t count = mesh->quads.size();
1638            for (size_t i = 0; i < count; i++) {
1639                const Rect& bounds = mesh->quads.itemAt(i);
1640                if (CC_LIKELY(pureTranslate)) {
1641                    const float x = (int) floorf(bounds.left + offsetX + 0.5f);
1642                    const float y = (int) floorf(bounds.top + offsetY + 0.5f);
1643                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight());
1644                } else {
1645                    dirtyLayer(left + bounds.left, top + bounds.top,
1646                            left + bounds.right, top + bounds.bottom, *mSnapshot->transform);
1647                }
1648            }
1649        }
1650#endif
1651
1652        if (CC_LIKELY(pureTranslate)) {
1653            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1654            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1655
1656            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1657                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1658                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1659                    true, !mesh->hasEmptyQuads);
1660        } else {
1661            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1662                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1663                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1664                    true, !mesh->hasEmptyQuads);
1665        }
1666    }
1667}
1668
1669/**
1670 * This function uses a similar approach to that of AA lines in the drawLines() function.
1671 * We expand the rectangle by a half pixel in screen space on all sides, and use a fragment
1672 * shader to compute the translucency of the color, determined by whether a given pixel is
1673 * within that boundary region and how far into the region it is.
1674 */
1675void OpenGLRenderer::drawAARect(float left, float top, float right, float bottom,
1676        int color, SkXfermode::Mode mode) {
1677    float inverseScaleX = 1.0f;
1678    float inverseScaleY = 1.0f;
1679    // The quad that we use needs to account for scaling.
1680    if (CC_UNLIKELY(!mSnapshot->transform->isPureTranslate())) {
1681        Matrix4 *mat = mSnapshot->transform;
1682        float m00 = mat->data[Matrix4::kScaleX];
1683        float m01 = mat->data[Matrix4::kSkewY];
1684        float m02 = mat->data[2];
1685        float m10 = mat->data[Matrix4::kSkewX];
1686        float m11 = mat->data[Matrix4::kScaleX];
1687        float m12 = mat->data[6];
1688        float scaleX = sqrt(m00 * m00 + m01 * m01);
1689        float scaleY = sqrt(m10 * m10 + m11 * m11);
1690        inverseScaleX = (scaleX != 0) ? (inverseScaleX / scaleX) : 0;
1691        inverseScaleY = (scaleY != 0) ? (inverseScaleY / scaleY) : 0;
1692    }
1693
1694    setupDraw();
1695    setupDrawNoTexture();
1696    setupDrawAALine();
1697    setupDrawColor(color);
1698    setupDrawColorFilter();
1699    setupDrawShader();
1700    setupDrawBlending(true, mode);
1701    setupDrawProgram();
1702    setupDrawModelViewIdentity(true);
1703    setupDrawColorUniforms();
1704    setupDrawColorFilterUniforms();
1705    setupDrawShaderIdentityUniforms();
1706
1707    AAVertex rects[4];
1708    AAVertex* aaVertices = &rects[0];
1709    void* widthCoords = ((GLbyte*) aaVertices) + gVertexAAWidthOffset;
1710    void* lengthCoords = ((GLbyte*) aaVertices) + gVertexAALengthOffset;
1711
1712    float boundarySizeX = .5 * inverseScaleX;
1713    float boundarySizeY = .5 * inverseScaleY;
1714
1715    // Adjust the rect by the AA boundary padding
1716    left -= boundarySizeX;
1717    right += boundarySizeX;
1718    top -= boundarySizeY;
1719    bottom += boundarySizeY;
1720
1721    float width = right - left;
1722    float height = bottom - top;
1723
1724    float boundaryWidthProportion = (width != 0) ? (2 * boundarySizeX) / width : 0;
1725    float boundaryHeightProportion = (height != 0) ? (2 * boundarySizeY) / height : 0;
1726    setupDrawAALine((void*) aaVertices, widthCoords, lengthCoords, boundaryWidthProportion);
1727    int boundaryLengthSlot = mCaches.currentProgram->getUniform("boundaryLength");
1728    int inverseBoundaryLengthSlot = mCaches.currentProgram->getUniform("inverseBoundaryLength");
1729    glUniform1f(boundaryLengthSlot, boundaryHeightProportion);
1730    glUniform1f(inverseBoundaryLengthSlot, (1 / boundaryHeightProportion));
1731
1732    if (!quickReject(left, top, right, bottom)) {
1733        AAVertex::set(aaVertices++, left, bottom, 1, 1);
1734        AAVertex::set(aaVertices++, left, top, 1, 0);
1735        AAVertex::set(aaVertices++, right, bottom, 0, 1);
1736        AAVertex::set(aaVertices++, right, top, 0, 0);
1737        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
1738        glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1739    }
1740}
1741
1742/**
1743 * We draw lines as quads (tristrips). Using GL_LINES can be difficult because the rasterization
1744 * rules for those lines produces some unexpected results, and may vary between hardware devices.
1745 * The basics of lines-as-quads is easy; we simply find the normal to the line and position the
1746 * corners of the quads on either side of each line endpoint, separated by the strokeWidth
1747 * of the line. Hairlines are more involved because we need to account for transform scaling
1748 * to end up with a one-pixel-wide line in screen space..
1749 * Anti-aliased lines add another factor to the approach. We use a specialized fragment shader
1750 * in combination with values that we calculate and pass down in this method. The basic approach
1751 * is that the quad we create contains both the core line area plus a bounding area in which
1752 * the translucent/AA pixels are drawn. The values we calculate tell the shader what
1753 * proportion of the width and the length of a given segment is represented by the boundary
1754 * region. The quad ends up being exactly .5 pixel larger in all directions than the non-AA quad.
1755 * The bounding region is actually 1 pixel wide on all sides (half pixel on the outside, half pixel
1756 * on the inside). This ends up giving the result we want, with pixels that are completely
1757 * 'inside' the line area being filled opaquely and the other pixels being filled according to
1758 * how far into the boundary region they are, which is determined by shader interpolation.
1759 */
1760void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1761    if (mSnapshot->isIgnored()) return;
1762
1763    const bool isAA = paint->isAntiAlias();
1764    // We use half the stroke width here because we're going to position the quad
1765    // corner vertices half of the width away from the line endpoints
1766    float halfStrokeWidth = paint->getStrokeWidth() * 0.5f;
1767    // A stroke width of 0 has a special meaning in Skia:
1768    // it draws a line 1 px wide regardless of current transform
1769    bool isHairLine = paint->getStrokeWidth() == 0.0f;
1770    float inverseScaleX = 1.0f;
1771    float inverseScaleY = 1.0f;
1772    bool scaled = false;
1773    int alpha;
1774    SkXfermode::Mode mode;
1775    int generatedVerticesCount = 0;
1776    int verticesCount = count;
1777    if (count > 4) {
1778        // Polyline: account for extra vertices needed for continuous tri-strip
1779        verticesCount += (count - 4);
1780    }
1781
1782    if (isHairLine || isAA) {
1783        // The quad that we use for AA and hairlines needs to account for scaling. For hairlines
1784        // the line on the screen should always be one pixel wide regardless of scale. For
1785        // AA lines, we only want one pixel of translucent boundary around the quad.
1786        if (CC_UNLIKELY(!mSnapshot->transform->isPureTranslate())) {
1787            Matrix4 *mat = mSnapshot->transform;
1788            float m00 = mat->data[Matrix4::kScaleX];
1789            float m01 = mat->data[Matrix4::kSkewY];
1790            float m02 = mat->data[2];
1791            float m10 = mat->data[Matrix4::kSkewX];
1792            float m11 = mat->data[Matrix4::kScaleX];
1793            float m12 = mat->data[6];
1794            float scaleX = sqrtf(m00 * m00 + m01 * m01);
1795            float scaleY = sqrtf(m10 * m10 + m11 * m11);
1796            inverseScaleX = (scaleX != 0) ? (inverseScaleX / scaleX) : 0;
1797            inverseScaleY = (scaleY != 0) ? (inverseScaleY / scaleY) : 0;
1798            if (inverseScaleX != 1.0f || inverseScaleY != 1.0f) {
1799                scaled = true;
1800            }
1801        }
1802    }
1803
1804    getAlphaAndMode(paint, &alpha, &mode);
1805    setupDraw();
1806    setupDrawNoTexture();
1807    if (isAA) {
1808        setupDrawAALine();
1809    }
1810    setupDrawColor(paint->getColor(), alpha);
1811    setupDrawColorFilter();
1812    setupDrawShader();
1813    setupDrawBlending(isAA, mode);
1814    setupDrawProgram();
1815    setupDrawModelViewIdentity(true);
1816    setupDrawColorUniforms();
1817    setupDrawColorFilterUniforms();
1818    setupDrawShaderIdentityUniforms();
1819
1820    if (isHairLine) {
1821        // Set a real stroke width to be used in quad construction
1822        halfStrokeWidth = isAA? 1 : .5;
1823    } else if (isAA && !scaled) {
1824        // Expand boundary to enable AA calculations on the quad border
1825        halfStrokeWidth += .5f;
1826    }
1827    Vertex lines[verticesCount];
1828    Vertex* vertices = &lines[0];
1829    AAVertex wLines[verticesCount];
1830    AAVertex* aaVertices = &wLines[0];
1831    if (CC_UNLIKELY(!isAA)) {
1832        setupDrawVertices(vertices);
1833    } else {
1834        void* widthCoords = ((GLbyte*) aaVertices) + gVertexAAWidthOffset;
1835        void* lengthCoords = ((GLbyte*) aaVertices) + gVertexAALengthOffset;
1836        // innerProportion is the ratio of the inner (non-AA) part of the line to the total
1837        // AA stroke width (the base stroke width expanded by a half pixel on either side).
1838        // This value is used in the fragment shader to determine how to fill fragments.
1839        // We will need to calculate the actual width proportion on each segment for
1840        // scaled non-hairlines, since the boundary proportion may differ per-axis when scaled.
1841        float boundaryWidthProportion = 1 / (2 * halfStrokeWidth);
1842        setupDrawAALine((void*) aaVertices, widthCoords, lengthCoords, boundaryWidthProportion);
1843    }
1844
1845    AAVertex* prevAAVertex = NULL;
1846    Vertex* prevVertex = NULL;
1847
1848    int boundaryLengthSlot = -1;
1849    int inverseBoundaryLengthSlot = -1;
1850    int boundaryWidthSlot = -1;
1851    int inverseBoundaryWidthSlot = -1;
1852    for (int i = 0; i < count; i += 4) {
1853        // a = start point, b = end point
1854        vec2 a(points[i], points[i + 1]);
1855        vec2 b(points[i + 2], points[i + 3]);
1856        float length = 0;
1857        float boundaryLengthProportion = 0;
1858        float boundaryWidthProportion = 0;
1859
1860        // Find the normal to the line
1861        vec2 n = (b - a).copyNormalized() * halfStrokeWidth;
1862        if (isHairLine) {
1863            if (isAA) {
1864                float wideningFactor;
1865                if (fabs(n.x) >= fabs(n.y)) {
1866                    wideningFactor = fabs(1.0f / n.x);
1867                } else {
1868                    wideningFactor = fabs(1.0f / n.y);
1869                }
1870                n *= wideningFactor;
1871            }
1872            if (scaled) {
1873                n.x *= inverseScaleX;
1874                n.y *= inverseScaleY;
1875            }
1876        } else if (scaled) {
1877            // Extend n by .5 pixel on each side, post-transform
1878            vec2 extendedN = n.copyNormalized();
1879            extendedN /= 2;
1880            extendedN.x *= inverseScaleX;
1881            extendedN.y *= inverseScaleY;
1882            float extendedNLength = extendedN.length();
1883            // We need to set this value on the shader prior to drawing
1884            boundaryWidthProportion = extendedNLength / (halfStrokeWidth + extendedNLength);
1885            n += extendedN;
1886        }
1887        float x = n.x;
1888        n.x = -n.y;
1889        n.y = x;
1890
1891        // aa lines expand the endpoint vertices to encompass the AA boundary
1892        if (isAA) {
1893            vec2 abVector = (b - a);
1894            length = abVector.length();
1895            abVector.normalize();
1896            if (scaled) {
1897                abVector.x *= inverseScaleX;
1898                abVector.y *= inverseScaleY;
1899                float abLength = abVector.length();
1900                boundaryLengthProportion = abLength / (length + abLength);
1901            } else {
1902                boundaryLengthProportion = .5 / (length + 1);
1903            }
1904            abVector /= 2;
1905            a -= abVector;
1906            b += abVector;
1907        }
1908
1909        // Four corners of the rectangle defining a thick line
1910        vec2 p1 = a - n;
1911        vec2 p2 = a + n;
1912        vec2 p3 = b + n;
1913        vec2 p4 = b - n;
1914
1915
1916        const float left = fmin(p1.x, fmin(p2.x, fmin(p3.x, p4.x)));
1917        const float right = fmax(p1.x, fmax(p2.x, fmax(p3.x, p4.x)));
1918        const float top = fmin(p1.y, fmin(p2.y, fmin(p3.y, p4.y)));
1919        const float bottom = fmax(p1.y, fmax(p2.y, fmax(p3.y, p4.y)));
1920
1921        if (!quickReject(left, top, right, bottom)) {
1922            if (!isAA) {
1923                if (prevVertex != NULL) {
1924                    // Issue two repeat vertices to create degenerate triangles to bridge
1925                    // between the previous line and the new one. This is necessary because
1926                    // we are creating a single triangle_strip which will contain
1927                    // potentially discontinuous line segments.
1928                    Vertex::set(vertices++, prevVertex->position[0], prevVertex->position[1]);
1929                    Vertex::set(vertices++, p1.x, p1.y);
1930                    generatedVerticesCount += 2;
1931                }
1932                Vertex::set(vertices++, p1.x, p1.y);
1933                Vertex::set(vertices++, p2.x, p2.y);
1934                Vertex::set(vertices++, p4.x, p4.y);
1935                Vertex::set(vertices++, p3.x, p3.y);
1936                prevVertex = vertices - 1;
1937                generatedVerticesCount += 4;
1938            } else {
1939                if (!isHairLine && scaled) {
1940                    // Must set width proportions per-segment for scaled non-hairlines to use the
1941                    // correct AA boundary dimensions
1942                    if (boundaryWidthSlot < 0) {
1943                        boundaryWidthSlot =
1944                                mCaches.currentProgram->getUniform("boundaryWidth");
1945                        inverseBoundaryWidthSlot =
1946                                mCaches.currentProgram->getUniform("inverseBoundaryWidth");
1947                    }
1948                    glUniform1f(boundaryWidthSlot, boundaryWidthProportion);
1949                    glUniform1f(inverseBoundaryWidthSlot, (1 / boundaryWidthProportion));
1950                }
1951                if (boundaryLengthSlot < 0) {
1952                    boundaryLengthSlot = mCaches.currentProgram->getUniform("boundaryLength");
1953                    inverseBoundaryLengthSlot =
1954                            mCaches.currentProgram->getUniform("inverseBoundaryLength");
1955                }
1956                glUniform1f(boundaryLengthSlot, boundaryLengthProportion);
1957                glUniform1f(inverseBoundaryLengthSlot, (1 / boundaryLengthProportion));
1958
1959                if (prevAAVertex != NULL) {
1960                    // Issue two repeat vertices to create degenerate triangles to bridge
1961                    // between the previous line and the new one. This is necessary because
1962                    // we are creating a single triangle_strip which will contain
1963                    // potentially discontinuous line segments.
1964                    AAVertex::set(aaVertices++,prevAAVertex->position[0],
1965                            prevAAVertex->position[1], prevAAVertex->width, prevAAVertex->length);
1966                    AAVertex::set(aaVertices++, p4.x, p4.y, 1, 1);
1967                    generatedVerticesCount += 2;
1968                }
1969                AAVertex::set(aaVertices++, p4.x, p4.y, 1, 1);
1970                AAVertex::set(aaVertices++, p1.x, p1.y, 1, 0);
1971                AAVertex::set(aaVertices++, p3.x, p3.y, 0, 1);
1972                AAVertex::set(aaVertices++, p2.x, p2.y, 0, 0);
1973                prevAAVertex = aaVertices - 1;
1974                generatedVerticesCount += 4;
1975            }
1976            dirtyLayer(a.x == b.x ? left - 1 : left, a.y == b.y ? top - 1 : top,
1977                    a.x == b.x ? right: right, a.y == b.y ? bottom: bottom,
1978                    *mSnapshot->transform);
1979        }
1980    }
1981    if (generatedVerticesCount > 0) {
1982       glDrawArrays(GL_TRIANGLE_STRIP, 0, generatedVerticesCount);
1983    }
1984}
1985
1986void OpenGLRenderer::drawPoints(float* points, int count, SkPaint* paint) {
1987    if (mSnapshot->isIgnored()) return;
1988
1989    // TODO: The paint's cap style defines whether the points are square or circular
1990    // TODO: Handle AA for round points
1991
1992    // A stroke width of 0 has a special meaning in Skia:
1993    // it draws an unscaled 1px point
1994    float strokeWidth = paint->getStrokeWidth();
1995    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1996    if (isHairLine) {
1997        // Now that we know it's hairline, we can set the effective width, to be used later
1998        strokeWidth = 1.0f;
1999    }
2000    const float halfWidth = strokeWidth / 2;
2001    int alpha;
2002    SkXfermode::Mode mode;
2003    getAlphaAndMode(paint, &alpha, &mode);
2004
2005    int verticesCount = count >> 1;
2006    int generatedVerticesCount = 0;
2007
2008    TextureVertex pointsData[verticesCount];
2009    TextureVertex* vertex = &pointsData[0];
2010
2011    setupDraw();
2012    setupDrawNoTexture();
2013    setupDrawPoint(strokeWidth);
2014    setupDrawColor(paint->getColor(), alpha);
2015    setupDrawColorFilter();
2016    setupDrawShader();
2017    setupDrawBlending(mode);
2018    setupDrawProgram();
2019    setupDrawModelViewIdentity(true);
2020    setupDrawColorUniforms();
2021    setupDrawColorFilterUniforms();
2022    setupDrawPointUniforms();
2023    setupDrawShaderIdentityUniforms();
2024    setupDrawMesh(vertex);
2025
2026    for (int i = 0; i < count; i += 2) {
2027        TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
2028        generatedVerticesCount++;
2029        float left = points[i] - halfWidth;
2030        float right = points[i] + halfWidth;
2031        float top = points[i + 1] - halfWidth;
2032        float bottom = points [i + 1] + halfWidth;
2033        dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
2034    }
2035
2036    glDrawArrays(GL_POINTS, 0, generatedVerticesCount);
2037}
2038
2039void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
2040    // No need to check against the clip, we fill the clip region
2041    if (mSnapshot->isIgnored()) return;
2042
2043    Rect& clip(*mSnapshot->clipRect);
2044    clip.snapToPixelBoundaries();
2045
2046    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
2047}
2048
2049void OpenGLRenderer::drawShape(float left, float top, const PathTexture* texture, SkPaint* paint) {
2050    if (!texture) return;
2051    const AutoTexture autoCleanup(texture);
2052
2053    const float x = left + texture->left - texture->offset;
2054    const float y = top + texture->top - texture->offset;
2055
2056    drawPathTexture(texture, x, y, paint);
2057}
2058
2059void OpenGLRenderer::drawRoundRect(float left, float top, float right, float bottom,
2060        float rx, float ry, SkPaint* paint) {
2061    if (mSnapshot->isIgnored()) return;
2062
2063    mCaches.activeTexture(0);
2064    const PathTexture* texture = mCaches.roundRectShapeCache.getRoundRect(
2065            right - left, bottom - top, rx, ry, paint);
2066    drawShape(left, top, texture, paint);
2067}
2068
2069void OpenGLRenderer::drawCircle(float x, float y, float radius, SkPaint* paint) {
2070    if (mSnapshot->isIgnored()) return;
2071
2072    mCaches.activeTexture(0);
2073    const PathTexture* texture = mCaches.circleShapeCache.getCircle(radius, paint);
2074    drawShape(x - radius, y - radius, texture, paint);
2075}
2076
2077void OpenGLRenderer::drawOval(float left, float top, float right, float bottom, SkPaint* paint) {
2078    if (mSnapshot->isIgnored()) return;
2079
2080    mCaches.activeTexture(0);
2081    const PathTexture* texture = mCaches.ovalShapeCache.getOval(right - left, bottom - top, paint);
2082    drawShape(left, top, texture, paint);
2083}
2084
2085void OpenGLRenderer::drawArc(float left, float top, float right, float bottom,
2086        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
2087    if (mSnapshot->isIgnored()) return;
2088
2089    if (fabs(sweepAngle) >= 360.0f) {
2090        drawOval(left, top, right, bottom, paint);
2091        return;
2092    }
2093
2094    mCaches.activeTexture(0);
2095    const PathTexture* texture = mCaches.arcShapeCache.getArc(right - left, bottom - top,
2096            startAngle, sweepAngle, useCenter, paint);
2097    drawShape(left, top, texture, paint);
2098}
2099
2100void OpenGLRenderer::drawRectAsShape(float left, float top, float right, float bottom,
2101        SkPaint* paint) {
2102    if (mSnapshot->isIgnored()) return;
2103
2104    mCaches.activeTexture(0);
2105    const PathTexture* texture = mCaches.rectShapeCache.getRect(right - left, bottom - top, paint);
2106    drawShape(left, top, texture, paint);
2107}
2108
2109void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
2110    if (p->getStyle() != SkPaint::kFill_Style) {
2111        drawRectAsShape(left, top, right, bottom, p);
2112        return;
2113    }
2114
2115    if (quickReject(left, top, right, bottom)) {
2116        return;
2117    }
2118
2119    SkXfermode::Mode mode;
2120    if (!mCaches.extensions.hasFramebufferFetch()) {
2121        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
2122        if (!isMode) {
2123            // Assume SRC_OVER
2124            mode = SkXfermode::kSrcOver_Mode;
2125        }
2126    } else {
2127        mode = getXfermode(p->getXfermode());
2128    }
2129
2130    int color = p->getColor();
2131    if (p->isAntiAlias() && !mSnapshot->transform->isSimple()) {
2132        drawAARect(left, top, right, bottom, color, mode);
2133    } else {
2134        drawColorRect(left, top, right, bottom, color, mode);
2135    }
2136}
2137
2138void OpenGLRenderer::drawPosText(const char* text, int bytesCount, int count,
2139        const float* positions, SkPaint* paint) {
2140    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2141            (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
2142        return;
2143    }
2144
2145    // NOTE: Skia does not support perspective transform on drawPosText yet
2146    if (!mSnapshot->transform->isSimple()) {
2147        return;
2148    }
2149
2150    float x = 0.0f;
2151    float y = 0.0f;
2152    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
2153    if (pureTranslate) {
2154        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2155        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2156    }
2157
2158    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
2159    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2160            paint->getTextSize());
2161
2162    int alpha;
2163    SkXfermode::Mode mode;
2164    getAlphaAndMode(paint, &alpha, &mode);
2165
2166    // Pick the appropriate texture filtering
2167    bool linearFilter = mSnapshot->transform->changesBounds();
2168    if (pureTranslate && !linearFilter) {
2169        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2170    }
2171
2172    mCaches.activeTexture(0);
2173    setupDraw();
2174    setupDrawDirtyRegionsDisabled();
2175    setupDrawWithTexture(true);
2176    setupDrawAlpha8Color(paint->getColor(), alpha);
2177    setupDrawColorFilter();
2178    setupDrawShader();
2179    setupDrawBlending(true, mode);
2180    setupDrawProgram();
2181    setupDrawModelView(x, y, x, y, pureTranslate, true);
2182    setupDrawTexture(fontRenderer.getTexture(linearFilter));
2183    setupDrawPureColorUniforms();
2184    setupDrawColorFilterUniforms();
2185    setupDrawShaderUniforms(pureTranslate);
2186
2187    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2188    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2189
2190#if RENDER_LAYERS_AS_REGIONS
2191    const bool hasActiveLayer = hasLayer();
2192#else
2193    const bool hasActiveLayer = false;
2194#endif
2195
2196    if (fontRenderer.renderPosText(paint, clip, text, 0, bytesCount, count, x, y,
2197            positions, hasActiveLayer ? &bounds : NULL)) {
2198#if RENDER_LAYERS_AS_REGIONS
2199        if (hasActiveLayer) {
2200            if (!pureTranslate) {
2201                mSnapshot->transform->mapRect(bounds);
2202            }
2203            dirtyLayerUnchecked(bounds, getRegion());
2204        }
2205#endif
2206    }
2207}
2208
2209void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
2210        float x, float y, SkPaint* paint, float length) {
2211    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2212            (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
2213        return;
2214    }
2215
2216    if (length < 0.0f) length = paint->measureText(text, bytesCount);
2217    switch (paint->getTextAlign()) {
2218        case SkPaint::kCenter_Align:
2219            x -= length / 2.0f;
2220            break;
2221        case SkPaint::kRight_Align:
2222            x -= length;
2223            break;
2224        default:
2225            break;
2226    }
2227
2228    SkPaint::FontMetrics metrics;
2229    paint->getFontMetrics(&metrics, 0.0f);
2230    if (quickReject(x, y + metrics.fTop, x + length, y + metrics.fBottom)) {
2231        return;
2232    }
2233
2234    const float oldX = x;
2235    const float oldY = y;
2236    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
2237    if (CC_LIKELY(pureTranslate)) {
2238        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2239        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2240    }
2241
2242#if DEBUG_GLYPHS
2243    ALOGD("OpenGLRenderer drawText() with FontID=%d", SkTypeface::UniqueID(paint->getTypeface()));
2244#endif
2245
2246    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
2247    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2248            paint->getTextSize());
2249
2250    int alpha;
2251    SkXfermode::Mode mode;
2252    getAlphaAndMode(paint, &alpha, &mode);
2253
2254    if (CC_UNLIKELY(mHasShadow)) {
2255        mCaches.activeTexture(0);
2256
2257        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
2258        const ShadowTexture* shadow = mCaches.dropShadowCache.get(
2259                paint, text, bytesCount, count, mShadowRadius);
2260        const AutoTexture autoCleanup(shadow);
2261
2262        const float sx = oldX - shadow->left + mShadowDx;
2263        const float sy = oldY - shadow->top + mShadowDy;
2264
2265        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
2266        int shadowColor = mShadowColor;
2267        if (mShader) {
2268            shadowColor = 0xffffffff;
2269        }
2270
2271        setupDraw();
2272        setupDrawWithTexture(true);
2273        setupDrawAlpha8Color(shadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
2274        setupDrawColorFilter();
2275        setupDrawShader();
2276        setupDrawBlending(true, mode);
2277        setupDrawProgram();
2278        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height);
2279        setupDrawTexture(shadow->id);
2280        setupDrawPureColorUniforms();
2281        setupDrawColorFilterUniforms();
2282        setupDrawShaderUniforms();
2283        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2284
2285        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2286    }
2287
2288    // Pick the appropriate texture filtering
2289    bool linearFilter = mSnapshot->transform->changesBounds();
2290    if (pureTranslate && !linearFilter) {
2291        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
2292    }
2293
2294    mCaches.activeTexture(0);
2295    setupDraw();
2296    setupDrawDirtyRegionsDisabled();
2297    setupDrawWithTexture(true);
2298    setupDrawAlpha8Color(paint->getColor(), alpha);
2299    setupDrawColorFilter();
2300    setupDrawShader();
2301    setupDrawBlending(true, mode);
2302    setupDrawProgram();
2303    setupDrawModelView(x, y, x, y, pureTranslate, true);
2304    setupDrawTexture(fontRenderer.getTexture(linearFilter));
2305    setupDrawPureColorUniforms();
2306    setupDrawColorFilterUniforms();
2307    setupDrawShaderUniforms(pureTranslate);
2308
2309    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
2310    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2311
2312#if RENDER_LAYERS_AS_REGIONS
2313    const bool hasActiveLayer = hasLayer();
2314#else
2315    const bool hasActiveLayer = false;
2316#endif
2317
2318    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
2319            hasActiveLayer ? &bounds : NULL)) {
2320#if RENDER_LAYERS_AS_REGIONS
2321        if (hasActiveLayer) {
2322            if (!pureTranslate) {
2323                mSnapshot->transform->mapRect(bounds);
2324            }
2325            dirtyLayerUnchecked(bounds, getRegion());
2326        }
2327#endif
2328    }
2329
2330    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
2331}
2332
2333void OpenGLRenderer::drawTextOnPath(const char* text, int bytesCount, int count, SkPath* path,
2334        float hOffset, float vOffset, SkPaint* paint) {
2335    if (text == NULL || count == 0 || mSnapshot->isIgnored() ||
2336            (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
2337        return;
2338    }
2339
2340    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
2341    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
2342            paint->getTextSize());
2343
2344    int alpha;
2345    SkXfermode::Mode mode;
2346    getAlphaAndMode(paint, &alpha, &mode);
2347
2348    mCaches.activeTexture(0);
2349    setupDraw();
2350    setupDrawDirtyRegionsDisabled();
2351    setupDrawWithTexture(true);
2352    setupDrawAlpha8Color(paint->getColor(), alpha);
2353    setupDrawColorFilter();
2354    setupDrawShader();
2355    setupDrawBlending(true, mode);
2356    setupDrawProgram();
2357    setupDrawModelView(0.0f, 0.0f, 0.0f, 0.0f, false, true);
2358    setupDrawTexture(fontRenderer.getTexture(true));
2359    setupDrawPureColorUniforms();
2360    setupDrawColorFilterUniforms();
2361    setupDrawShaderUniforms(false);
2362
2363    const Rect* clip = &mSnapshot->getLocalClip();
2364    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
2365
2366#if RENDER_LAYERS_AS_REGIONS
2367    const bool hasActiveLayer = hasLayer();
2368#else
2369    const bool hasActiveLayer = false;
2370#endif
2371
2372    if (fontRenderer.renderTextOnPath(paint, clip, text, 0, bytesCount, count, path,
2373            hOffset, vOffset, hasActiveLayer ? &bounds : NULL)) {
2374#if RENDER_LAYERS_AS_REGIONS
2375        if (hasActiveLayer) {
2376            mSnapshot->transform->mapRect(bounds);
2377            dirtyLayerUnchecked(bounds, getRegion());
2378        }
2379#endif
2380    }
2381}
2382
2383void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
2384    if (mSnapshot->isIgnored()) return;
2385
2386    mCaches.activeTexture(0);
2387
2388    // TODO: Perform early clip test before we rasterize the path
2389    const PathTexture* texture = mCaches.pathCache.get(path, paint);
2390    if (!texture) return;
2391    const AutoTexture autoCleanup(texture);
2392
2393    const float x = texture->left - texture->offset;
2394    const float y = texture->top - texture->offset;
2395
2396    drawPathTexture(texture, x, y, paint);
2397}
2398
2399void OpenGLRenderer::drawLayer(Layer* layer, float x, float y, SkPaint* paint) {
2400    if (!layer || quickReject(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight())) {
2401        return;
2402    }
2403
2404    if (layer->deferredUpdateScheduled && layer->renderer && layer->displayList) {
2405        OpenGLRenderer* renderer = layer->renderer;
2406        Rect& dirty = layer->dirtyRect;
2407
2408        interrupt();
2409        renderer->setViewport(layer->layer.getWidth(), layer->layer.getHeight());
2410        renderer->prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, !layer->isBlend());
2411        renderer->drawDisplayList(layer->displayList, layer->getWidth(), layer->getHeight(),
2412                dirty, DisplayList::kReplayFlag_ClipChildren);
2413        renderer->finish();
2414        resume();
2415
2416        dirty.setEmpty();
2417        layer->deferredUpdateScheduled = false;
2418        layer->renderer = NULL;
2419        layer->displayList = NULL;
2420    }
2421
2422    mCaches.activeTexture(0);
2423
2424    int alpha;
2425    SkXfermode::Mode mode;
2426    getAlphaAndMode(paint, &alpha, &mode);
2427
2428    layer->setAlpha(alpha, mode);
2429
2430#if RENDER_LAYERS_AS_REGIONS
2431    if (CC_LIKELY(!layer->region.isEmpty())) {
2432        if (layer->region.isRect()) {
2433            composeLayerRect(layer, layer->regionRect);
2434        } else if (layer->mesh) {
2435            const float a = alpha / 255.0f;
2436            const Rect& rect = layer->layer;
2437
2438            setupDraw();
2439            setupDrawWithTexture();
2440            setupDrawColor(a, a, a, a);
2441            setupDrawColorFilter();
2442            setupDrawBlending(layer->isBlend() || a < 1.0f, layer->getMode(), false);
2443            setupDrawProgram();
2444            setupDrawPureColorUniforms();
2445            setupDrawColorFilterUniforms();
2446            setupDrawTexture(layer->getTexture());
2447            if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
2448                x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
2449                y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
2450
2451                layer->setFilter(GL_NEAREST);
2452                setupDrawModelViewTranslate(x, y,
2453                        x + layer->layer.getWidth(), y + layer->layer.getHeight(), true);
2454            } else {
2455                layer->setFilter(GL_LINEAR);
2456                setupDrawModelViewTranslate(x, y,
2457                        x + layer->layer.getWidth(), y + layer->layer.getHeight());
2458            }
2459            setupDrawMesh(&layer->mesh[0].position[0], &layer->mesh[0].texture[0]);
2460
2461            glDrawElements(GL_TRIANGLES, layer->meshElementCount,
2462                    GL_UNSIGNED_SHORT, layer->meshIndices);
2463
2464            finishDrawTexture();
2465
2466#if DEBUG_LAYERS_AS_REGIONS
2467            drawRegionRects(layer->region);
2468#endif
2469        }
2470    }
2471#else
2472    const Rect r(x, y, x + layer->layer.getWidth(), y + layer->layer.getHeight());
2473    composeLayerRect(layer, r);
2474#endif
2475}
2476
2477///////////////////////////////////////////////////////////////////////////////
2478// Shaders
2479///////////////////////////////////////////////////////////////////////////////
2480
2481void OpenGLRenderer::resetShader() {
2482    mShader = NULL;
2483}
2484
2485void OpenGLRenderer::setupShader(SkiaShader* shader) {
2486    mShader = shader;
2487    if (mShader) {
2488        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
2489    }
2490}
2491
2492///////////////////////////////////////////////////////////////////////////////
2493// Color filters
2494///////////////////////////////////////////////////////////////////////////////
2495
2496void OpenGLRenderer::resetColorFilter() {
2497    mColorFilter = NULL;
2498}
2499
2500void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
2501    mColorFilter = filter;
2502}
2503
2504///////////////////////////////////////////////////////////////////////////////
2505// Drop shadow
2506///////////////////////////////////////////////////////////////////////////////
2507
2508void OpenGLRenderer::resetShadow() {
2509    mHasShadow = false;
2510}
2511
2512void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
2513    mHasShadow = true;
2514    mShadowRadius = radius;
2515    mShadowDx = dx;
2516    mShadowDy = dy;
2517    mShadowColor = color;
2518}
2519
2520///////////////////////////////////////////////////////////////////////////////
2521// Draw filters
2522///////////////////////////////////////////////////////////////////////////////
2523
2524void OpenGLRenderer::resetPaintFilter() {
2525    mHasDrawFilter = false;
2526}
2527
2528void OpenGLRenderer::setupPaintFilter(int clearBits, int setBits) {
2529    mHasDrawFilter = true;
2530    mPaintFilterClearBits = clearBits & SkPaint::kAllFlags;
2531    mPaintFilterSetBits = setBits & SkPaint::kAllFlags;
2532}
2533
2534SkPaint* OpenGLRenderer::filterPaint(SkPaint* paint) {
2535    if (CC_LIKELY(!mHasDrawFilter || !paint)) return paint;
2536
2537    uint32_t flags = paint->getFlags();
2538
2539    mFilteredPaint = *paint;
2540    mFilteredPaint.setFlags((flags & ~mPaintFilterClearBits) | mPaintFilterSetBits);
2541
2542    return &mFilteredPaint;
2543}
2544
2545///////////////////////////////////////////////////////////////////////////////
2546// Drawing implementation
2547///////////////////////////////////////////////////////////////////////////////
2548
2549void OpenGLRenderer::drawPathTexture(const PathTexture* texture,
2550        float x, float y, SkPaint* paint) {
2551    if (quickReject(x, y, x + texture->width, y + texture->height)) {
2552        return;
2553    }
2554
2555    int alpha;
2556    SkXfermode::Mode mode;
2557    getAlphaAndMode(paint, &alpha, &mode);
2558
2559    setupDraw();
2560    setupDrawWithTexture(true);
2561    setupDrawAlpha8Color(paint->getColor(), alpha);
2562    setupDrawColorFilter();
2563    setupDrawShader();
2564    setupDrawBlending(true, mode);
2565    setupDrawProgram();
2566    setupDrawModelView(x, y, x + texture->width, y + texture->height);
2567    setupDrawTexture(texture->id);
2568    setupDrawPureColorUniforms();
2569    setupDrawColorFilterUniforms();
2570    setupDrawShaderUniforms();
2571    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
2572
2573    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2574
2575    finishDrawTexture();
2576}
2577
2578// Same values used by Skia
2579#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
2580#define kStdUnderline_Offset    (1.0f / 9.0f)
2581#define kStdUnderline_Thickness (1.0f / 18.0f)
2582
2583void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
2584        float x, float y, SkPaint* paint) {
2585    // Handle underline and strike-through
2586    uint32_t flags = paint->getFlags();
2587    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
2588        SkPaint paintCopy(*paint);
2589        float underlineWidth = length;
2590        // If length is > 0.0f, we already measured the text for the text alignment
2591        if (length <= 0.0f) {
2592            underlineWidth = paintCopy.measureText(text, bytesCount);
2593        }
2594
2595        float offsetX = 0;
2596        switch (paintCopy.getTextAlign()) {
2597            case SkPaint::kCenter_Align:
2598                offsetX = underlineWidth * 0.5f;
2599                break;
2600            case SkPaint::kRight_Align:
2601                offsetX = underlineWidth;
2602                break;
2603            default:
2604                break;
2605        }
2606
2607        if (CC_LIKELY(underlineWidth > 0.0f)) {
2608            const float textSize = paintCopy.getTextSize();
2609            const float strokeWidth = fmax(textSize * kStdUnderline_Thickness, 1.0f);
2610
2611            const float left = x - offsetX;
2612            float top = 0.0f;
2613
2614            int linesCount = 0;
2615            if (flags & SkPaint::kUnderlineText_Flag) linesCount++;
2616            if (flags & SkPaint::kStrikeThruText_Flag) linesCount++;
2617
2618            const int pointsCount = 4 * linesCount;
2619            float points[pointsCount];
2620            int currentPoint = 0;
2621
2622            if (flags & SkPaint::kUnderlineText_Flag) {
2623                top = y + textSize * kStdUnderline_Offset;
2624                points[currentPoint++] = left;
2625                points[currentPoint++] = top;
2626                points[currentPoint++] = left + underlineWidth;
2627                points[currentPoint++] = top;
2628            }
2629
2630            if (flags & SkPaint::kStrikeThruText_Flag) {
2631                top = y + textSize * kStdStrikeThru_Offset;
2632                points[currentPoint++] = left;
2633                points[currentPoint++] = top;
2634                points[currentPoint++] = left + underlineWidth;
2635                points[currentPoint++] = top;
2636            }
2637
2638            paintCopy.setStrokeWidth(strokeWidth);
2639
2640            drawLines(&points[0], pointsCount, &paintCopy);
2641        }
2642    }
2643}
2644
2645void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
2646        int color, SkXfermode::Mode mode, bool ignoreTransform) {
2647    // If a shader is set, preserve only the alpha
2648    if (mShader) {
2649        color |= 0x00ffffff;
2650    }
2651
2652    setupDraw();
2653    setupDrawNoTexture();
2654    setupDrawColor(color);
2655    setupDrawShader();
2656    setupDrawColorFilter();
2657    setupDrawBlending(mode);
2658    setupDrawProgram();
2659    setupDrawModelView(left, top, right, bottom, ignoreTransform);
2660    setupDrawColorUniforms();
2661    setupDrawShaderUniforms(ignoreTransform);
2662    setupDrawColorFilterUniforms();
2663    setupDrawSimpleMesh();
2664
2665    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
2666}
2667
2668void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2669        Texture* texture, SkPaint* paint) {
2670    int alpha;
2671    SkXfermode::Mode mode;
2672    getAlphaAndMode(paint, &alpha, &mode);
2673
2674    texture->setWrap(GL_CLAMP_TO_EDGE, true);
2675
2676    if (CC_LIKELY(mSnapshot->transform->isPureTranslate())) {
2677        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
2678        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
2679
2680        texture->setFilter(GL_NEAREST, true);
2681        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
2682                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
2683                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
2684    } else {
2685        texture->setFilter(FILTER(paint), true);
2686        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
2687                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
2688                GL_TRIANGLE_STRIP, gMeshCount);
2689    }
2690}
2691
2692void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
2693        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
2694    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
2695            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
2696}
2697
2698void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
2699        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
2700        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
2701        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
2702
2703    setupDraw();
2704    setupDrawWithTexture();
2705    setupDrawColor(alpha, alpha, alpha, alpha);
2706    setupDrawColorFilter();
2707    setupDrawBlending(blend, mode, swapSrcDst);
2708    setupDrawProgram();
2709    if (!dirty) {
2710        setupDrawDirtyRegionsDisabled();
2711    }
2712    if (!ignoreScale) {
2713        setupDrawModelView(left, top, right, bottom, ignoreTransform);
2714    } else {
2715        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
2716    }
2717    setupDrawPureColorUniforms();
2718    setupDrawColorFilterUniforms();
2719    setupDrawTexture(texture);
2720    setupDrawMesh(vertices, texCoords, vbo);
2721
2722    glDrawArrays(drawMode, 0, elementsCount);
2723
2724    finishDrawTexture();
2725}
2726
2727void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
2728        ProgramDescription& description, bool swapSrcDst) {
2729    blend = blend || mode != SkXfermode::kSrcOver_Mode;
2730    if (blend) {
2731        // These blend modes are not supported by OpenGL directly and have
2732        // to be implemented using shaders. Since the shader will perform
2733        // the blending, turn blending off here
2734        // If the blend mode cannot be implemented using shaders, fall
2735        // back to the default SrcOver blend mode instead
2736        if CC_UNLIKELY((mode > SkXfermode::kScreen_Mode)) {
2737            if (CC_UNLIKELY(mCaches.extensions.hasFramebufferFetch())) {
2738                description.framebufferMode = mode;
2739                description.swapSrcDst = swapSrcDst;
2740
2741                if (mCaches.blend) {
2742                    glDisable(GL_BLEND);
2743                    mCaches.blend = false;
2744                }
2745
2746                return;
2747            } else {
2748                mode = SkXfermode::kSrcOver_Mode;
2749            }
2750        }
2751
2752        if (!mCaches.blend) {
2753            glEnable(GL_BLEND);
2754        }
2755
2756        GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
2757        GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
2758
2759        if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
2760            glBlendFunc(sourceMode, destMode);
2761            mCaches.lastSrcMode = sourceMode;
2762            mCaches.lastDstMode = destMode;
2763        }
2764    } else if (mCaches.blend) {
2765        glDisable(GL_BLEND);
2766    }
2767    mCaches.blend = blend;
2768}
2769
2770bool OpenGLRenderer::useProgram(Program* program) {
2771    if (!program->isInUse()) {
2772        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
2773        program->use();
2774        mCaches.currentProgram = program;
2775        return false;
2776    }
2777    return true;
2778}
2779
2780void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
2781    TextureVertex* v = &mMeshVertices[0];
2782    TextureVertex::setUV(v++, u1, v1);
2783    TextureVertex::setUV(v++, u2, v1);
2784    TextureVertex::setUV(v++, u1, v2);
2785    TextureVertex::setUV(v++, u2, v2);
2786}
2787
2788void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
2789    if (paint) {
2790        *mode = getXfermode(paint->getXfermode());
2791
2792        // Skia draws using the color's alpha channel if < 255
2793        // Otherwise, it uses the paint's alpha
2794        int color = paint->getColor();
2795        *alpha = (color >> 24) & 0xFF;
2796        if (*alpha == 255) {
2797            *alpha = paint->getAlpha();
2798        }
2799    } else {
2800        *mode = SkXfermode::kSrcOver_Mode;
2801        *alpha = 255;
2802    }
2803}
2804
2805SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
2806    SkXfermode::Mode resultMode;
2807    if (!SkXfermode::AsMode(mode, &resultMode)) {
2808        resultMode = SkXfermode::kSrcOver_Mode;
2809    }
2810    return resultMode;
2811}
2812
2813}; // namespace uirenderer
2814}; // namespace android
2815