OpenGLRenderer.cpp revision 9cccc2b9bdd4850a3f9679569aaec3ab98477a5d 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkTypeface.h>
25
26#include <cutils/properties.h>
27#include <utils/Log.h>
28
29#include "OpenGLRenderer.h"
30#include "Properties.h"
31
32namespace android {
33namespace uirenderer {
34
35///////////////////////////////////////////////////////////////////////////////
36// Defines
37///////////////////////////////////////////////////////////////////////////////
38
39#define DEFAULT_TEXTURE_CACHE_SIZE 20.0f
40#define DEFAULT_LAYER_CACHE_SIZE 6.0f
41#define DEFAULT_PATH_CACHE_SIZE 6.0f
42#define DEFAULT_PATCH_CACHE_SIZE 100
43#define DEFAULT_GRADIENT_CACHE_SIZE 0.5f
44
45#define REQUIRED_TEXTURE_UNITS_COUNT 3
46
47// Converts a number of mega-bytes into bytes
48#define MB(s) s * 1024 * 1024
49
50// Generates simple and textured vertices
51#define FV(x, y, u, v) { { x, y }, { u, v } }
52
53///////////////////////////////////////////////////////////////////////////////
54// Globals
55///////////////////////////////////////////////////////////////////////////////
56
57// This array is never used directly but used as a memcpy source in the
58// OpenGLRenderer constructor
59static const TextureVertex gMeshVertices[] = {
60        FV(0.0f, 0.0f, 0.0f, 0.0f),
61        FV(1.0f, 0.0f, 1.0f, 0.0f),
62        FV(0.0f, 1.0f, 0.0f, 1.0f),
63        FV(1.0f, 1.0f, 1.0f, 1.0f)
64};
65static const GLsizei gMeshStride = sizeof(TextureVertex);
66static const GLsizei gMeshCount = 4;
67
68/**
69 * Structure mapping Skia xfermodes to OpenGL blending factors.
70 */
71struct Blender {
72    SkXfermode::Mode mode;
73    GLenum src;
74    GLenum dst;
75}; // struct Blender
76
77// In this array, the index of each Blender equals the value of the first
78// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
79static const Blender gBlends[] = {
80        { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
81        { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
82        { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
83        { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
84        { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
85        { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
86        { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
87        { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
88        { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
89        { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
90        { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
91        { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
92};
93
94static const GLenum gTextureUnits[] = {
95        GL_TEXTURE0,
96        GL_TEXTURE1,
97        GL_TEXTURE2
98};
99
100///////////////////////////////////////////////////////////////////////////////
101// Constructors/destructor
102///////////////////////////////////////////////////////////////////////////////
103
104OpenGLRenderer::OpenGLRenderer():
105        mBlend(false), mLastSrcMode(GL_ZERO), mLastDstMode(GL_ZERO),
106        mTextureCache(MB(DEFAULT_TEXTURE_CACHE_SIZE)),
107        mLayerCache(MB(DEFAULT_LAYER_CACHE_SIZE)),
108        mGradientCache(MB(DEFAULT_GRADIENT_CACHE_SIZE)),
109        mPathCache(MB(DEFAULT_PATH_CACHE_SIZE)),
110        mPatchCache(DEFAULT_PATCH_CACHE_SIZE) {
111    LOGD("Create OpenGLRenderer");
112
113    char property[PROPERTY_VALUE_MAX];
114    if (property_get(PROPERTY_TEXTURE_CACHE_SIZE, property, NULL) > 0) {
115        LOGD("  Setting texture cache size to %sMB", property);
116        mTextureCache.setMaxSize(MB(atof(property)));
117    } else {
118        LOGD("  Using default texture cache size of %.2fMB", DEFAULT_TEXTURE_CACHE_SIZE);
119    }
120
121    if (property_get(PROPERTY_LAYER_CACHE_SIZE, property, NULL) > 0) {
122        LOGD("  Setting layer cache size to %sMB", property);
123        mLayerCache.setMaxSize(MB(atof(property)));
124    } else {
125        LOGD("  Using default layer cache size of %.2fMB", DEFAULT_LAYER_CACHE_SIZE);
126    }
127
128    if (property_get(PROPERTY_GRADIENT_CACHE_SIZE, property, NULL) > 0) {
129        LOGD("  Setting gradient cache size to %sMB", property);
130        mGradientCache.setMaxSize(MB(atof(property)));
131    } else {
132        LOGD("  Using default gradient cache size of %.2fMB", DEFAULT_GRADIENT_CACHE_SIZE);
133    }
134
135    if (property_get(PROPERTY_PATH_CACHE_SIZE, property, NULL) > 0) {
136        LOGD("  Setting path cache size to %sMB", property);
137        mPathCache.setMaxSize(MB(atof(property)));
138    } else {
139        LOGD("  Using default path cache size of %.2fMB", DEFAULT_PATH_CACHE_SIZE);
140    }
141
142    mCurrentProgram = NULL;
143    mShader = NULL;
144    mColorFilter = NULL;
145
146    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
147
148    mFirstSnapshot = new Snapshot;
149
150    GLint maxTextureUnits;
151    glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &maxTextureUnits);
152    if (maxTextureUnits < REQUIRED_TEXTURE_UNITS_COUNT) {
153        LOGW("At least %d texture units are required!", REQUIRED_TEXTURE_UNITS_COUNT);
154    }
155}
156
157OpenGLRenderer::~OpenGLRenderer() {
158    LOGD("Destroy OpenGLRenderer");
159
160    mTextureCache.clear();
161    mLayerCache.clear();
162    mGradientCache.clear();
163    mPatchCache.clear();
164}
165
166///////////////////////////////////////////////////////////////////////////////
167// Setup
168///////////////////////////////////////////////////////////////////////////////
169
170void OpenGLRenderer::setViewport(int width, int height) {
171    glViewport(0, 0, width, height);
172
173    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
174
175    mWidth = width;
176    mHeight = height;
177    mFirstSnapshot->height = height;
178}
179
180void OpenGLRenderer::prepare() {
181    mSnapshot = new Snapshot(mFirstSnapshot);
182    mSaveCount = 0;
183
184    glDisable(GL_SCISSOR_TEST);
185
186    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
187    glClear(GL_COLOR_BUFFER_BIT);
188
189    glEnable(GL_SCISSOR_TEST);
190    glScissor(0, 0, mWidth, mHeight);
191
192    mSnapshot->setClip(0.0f, 0.0f, mWidth, mHeight);
193}
194
195///////////////////////////////////////////////////////////////////////////////
196// State management
197///////////////////////////////////////////////////////////////////////////////
198
199int OpenGLRenderer::getSaveCount() const {
200    return mSaveCount;
201}
202
203int OpenGLRenderer::save(int flags) {
204    return saveSnapshot();
205}
206
207void OpenGLRenderer::restore() {
208    if (mSaveCount == 0) return;
209
210    if (restoreSnapshot()) {
211        setScissorFromClip();
212    }
213}
214
215void OpenGLRenderer::restoreToCount(int saveCount) {
216    if (saveCount <= 0 || saveCount > mSaveCount) return;
217
218    bool restoreClip = false;
219
220    while (mSaveCount != saveCount - 1) {
221        restoreClip |= restoreSnapshot();
222    }
223
224    if (restoreClip) {
225        setScissorFromClip();
226    }
227}
228
229int OpenGLRenderer::saveSnapshot() {
230    mSnapshot = new Snapshot(mSnapshot);
231    return ++mSaveCount;
232}
233
234bool OpenGLRenderer::restoreSnapshot() {
235    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
236    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
237    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
238
239    sp<Snapshot> current = mSnapshot;
240    sp<Snapshot> previous = mSnapshot->previous;
241
242    if (restoreOrtho) {
243        mOrthoMatrix.load(current->orthoMatrix);
244    }
245
246    if (restoreLayer) {
247        composeLayer(current, previous);
248    }
249
250    mSnapshot = previous;
251    mSaveCount--;
252
253    return restoreClip;
254}
255
256void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
257    if (!current->layer) {
258        LOGE("Attempting to compose a layer that does not exist");
259        return;
260    }
261
262    // Unbind current FBO and restore previous one
263    // Most of the time, previous->fbo will be 0 to bind the default buffer
264    glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
265
266    // Restore the clip from the previous snapshot
267    const Rect& clip = previous->clipRect;
268    glScissor(clip.left, mHeight - clip.bottom, clip.getWidth(), clip.getHeight());
269
270    Layer* layer = current->layer;
271    const Rect& rect = layer->layer;
272
273    drawTextureRect(rect.left, rect.top, rect.right, rect.bottom,
274            layer->texture, layer->alpha, layer->mode, layer->blend);
275
276    LayerSize size(rect.getWidth(), rect.getHeight());
277    // Failing to add the layer to the cache should happen only if the
278    // layer is too large
279    if (!mLayerCache.put(size, layer)) {
280        LAYER_LOGD("Deleting layer");
281
282        glDeleteFramebuffers(1, &layer->fbo);
283        glDeleteTextures(1, &layer->texture);
284
285        delete layer;
286    }
287}
288
289///////////////////////////////////////////////////////////////////////////////
290// Layers
291///////////////////////////////////////////////////////////////////////////////
292
293int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
294        const SkPaint* p, int flags) {
295    int count = saveSnapshot();
296
297    int alpha = 255;
298    SkXfermode::Mode mode;
299
300    if (p) {
301        alpha = p->getAlpha();
302        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
303        if (!isMode) {
304            // Assume SRC_OVER
305            mode = SkXfermode::kSrcOver_Mode;
306        }
307    } else {
308        mode = SkXfermode::kSrcOver_Mode;
309    }
310
311    createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags);
312
313    return count;
314}
315
316int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
317        int alpha, int flags) {
318    int count = saveSnapshot();
319    createLayer(mSnapshot, left, top, right, bottom, alpha, SkXfermode::kSrcOver_Mode, flags);
320    return count;
321}
322
323bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
324        float right, float bottom, int alpha, SkXfermode::Mode mode,int flags) {
325    LAYER_LOGD("Requesting layer %fx%f", right - left, bottom - top);
326    LAYER_LOGD("Layer cache size = %d", mLayerCache.getSize());
327
328    GLuint previousFbo = snapshot->previous.get() ? snapshot->previous->fbo : 0;
329    LayerSize size(right - left, bottom - top);
330
331    Layer* layer = mLayerCache.get(size, previousFbo);
332    if (!layer) {
333        return false;
334    }
335
336    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
337
338    // Clear the FBO
339    glDisable(GL_SCISSOR_TEST);
340    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
341    glClear(GL_COLOR_BUFFER_BIT);
342    glEnable(GL_SCISSOR_TEST);
343
344    // Save the layer in the snapshot
345    snapshot->flags |= Snapshot::kFlagIsLayer;
346    layer->mode = mode;
347    layer->alpha = alpha / 255.0f;
348    layer->layer.set(left, top, right, bottom);
349
350    snapshot->layer = layer;
351    snapshot->fbo = layer->fbo;
352
353    // Creates a new snapshot to draw into the FBO
354    saveSnapshot();
355    // TODO: This doesn't preserve other transformations (check Skia first)
356    mSnapshot->transform.loadTranslate(-left, -top, 0.0f);
357    mSnapshot->setClip(0.0f, 0.0f, right - left, bottom - top);
358    mSnapshot->height = bottom - top;
359    setScissorFromClip();
360
361    mSnapshot->flags = Snapshot::kFlagDirtyOrtho | Snapshot::kFlagClipSet;
362    mSnapshot->orthoMatrix.load(mOrthoMatrix);
363
364    // Change the ortho projection
365    mOrthoMatrix.loadOrtho(0.0f, right - left, bottom - top, 0.0f, 0.0f, 1.0f);
366
367    return true;
368}
369
370///////////////////////////////////////////////////////////////////////////////
371// Transforms
372///////////////////////////////////////////////////////////////////////////////
373
374void OpenGLRenderer::translate(float dx, float dy) {
375    mSnapshot->transform.translate(dx, dy, 0.0f);
376}
377
378void OpenGLRenderer::rotate(float degrees) {
379    mSnapshot->transform.rotate(degrees, 0.0f, 0.0f, 1.0f);
380}
381
382void OpenGLRenderer::scale(float sx, float sy) {
383    mSnapshot->transform.scale(sx, sy, 1.0f);
384}
385
386void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
387    mSnapshot->transform.load(*matrix);
388}
389
390void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
391    mSnapshot->transform.copyTo(*matrix);
392}
393
394void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
395    mat4 m(*matrix);
396    mSnapshot->transform.multiply(m);
397}
398
399///////////////////////////////////////////////////////////////////////////////
400// Clipping
401///////////////////////////////////////////////////////////////////////////////
402
403void OpenGLRenderer::setScissorFromClip() {
404    const Rect& clip = mSnapshot->clipRect;
405    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
406}
407
408const Rect& OpenGLRenderer::getClipBounds() {
409    return mSnapshot->getLocalClip();
410}
411
412bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
413    Rect r(left, top, right, bottom);
414    mSnapshot->transform.mapRect(r);
415    return !mSnapshot->clipRect.intersects(r);
416}
417
418bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
419    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
420    if (clipped) {
421        setScissorFromClip();
422    }
423    return !mSnapshot->clipRect.isEmpty();
424}
425
426///////////////////////////////////////////////////////////////////////////////
427// Drawing
428///////////////////////////////////////////////////////////////////////////////
429
430void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, const SkPaint* paint) {
431    const float right = left + bitmap->width();
432    const float bottom = top + bitmap->height();
433
434    if (quickReject(left, top, right, bottom)) {
435        return;
436    }
437
438    const Texture* texture = mTextureCache.get(bitmap);
439    if (!texture) return;
440    const AutoTexture autoCleanup(texture);
441
442    drawTextureRect(left, top, right, bottom, texture, paint);
443}
444
445void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, const SkMatrix* matrix, const SkPaint* paint) {
446    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
447    const mat4 transform(*matrix);
448    transform.mapRect(r);
449
450    if (quickReject(r.left, r.top, r.right, r.bottom)) {
451        return;
452    }
453
454    const Texture* texture = mTextureCache.get(bitmap);
455    if (!texture) return;
456    const AutoTexture autoCleanup(texture);
457
458    drawTextureRect(r.left, r.top, r.right, r.bottom, texture, paint);
459}
460
461void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
462         float srcLeft, float srcTop, float srcRight, float srcBottom,
463         float dstLeft, float dstTop, float dstRight, float dstBottom,
464         const SkPaint* paint) {
465    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
466        return;
467    }
468
469    const Texture* texture = mTextureCache.get(bitmap);
470    if (!texture) return;
471    const AutoTexture autoCleanup(texture);
472
473    const float width = texture->width;
474    const float height = texture->height;
475
476    const float u1 = srcLeft / width;
477    const float v1 = srcTop / height;
478    const float u2 = srcRight / width;
479    const float v2 = srcBottom / height;
480
481    resetDrawTextureTexCoords(u1, v1, u2, v2);
482
483    drawTextureRect(dstLeft, dstTop, dstRight, dstBottom, texture, paint);
484
485    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
486}
487
488void OpenGLRenderer::drawPatch(SkBitmap* bitmap, Res_png_9patch* patch,
489        float left, float top, float right, float bottom, const SkPaint* paint) {
490    if (quickReject(left, top, right, bottom)) {
491        return;
492    }
493
494    const Texture* texture = mTextureCache.get(bitmap);
495    if (!texture) return;
496    const AutoTexture autoCleanup(texture);
497
498    int alpha;
499    SkXfermode::Mode mode;
500    getAlphaAndMode(paint, &alpha, &mode);
501
502    Patch* mesh = mPatchCache.get(patch);
503    mesh->updateVertices(bitmap, left, top, right, bottom,
504            &patch->xDivs[0], &patch->yDivs[0], patch->numXDivs, patch->numYDivs);
505
506    // Specify right and bottom as +1.0f from left/top to prevent scaling since the
507    // patch mesh already defines the final size
508    drawTextureMesh(left, top, left + 1.0f, top + 1.0f, texture->id, alpha / 255.0f,
509            mode, texture->blend, &mesh->vertices[0].position[0],
510            &mesh->vertices[0].texture[0], mesh->indices, mesh->indicesCount);
511}
512
513void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
514    const Rect& clip = mSnapshot->clipRect;
515    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
516}
517
518void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, const SkPaint* p) {
519    if (quickReject(left, top, right, bottom)) {
520        return;
521    }
522
523    SkXfermode::Mode mode;
524
525    const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
526    if (!isMode) {
527        // Assume SRC_OVER
528        mode = SkXfermode::kSrcOver_Mode;
529    }
530
531    // Skia draws using the color's alpha channel if < 255
532    // Otherwise, it uses the paint's alpha
533    int color = p->getColor();
534    if (((color >> 24) & 0xff) == 255) {
535        color |= p->getAlpha() << 24;
536    }
537
538    drawColorRect(left, top, right, bottom, color, mode);
539}
540
541void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
542        float x, float y, SkPaint* paint) {
543    if (text == NULL || count == 0 || (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
544        return;
545    }
546
547    float length;
548    switch (paint->getTextAlign()) {
549        case SkPaint::kCenter_Align:
550            length = paint->measureText(text, bytesCount);
551            x -= length / 2.0f;
552            break;
553        case SkPaint::kRight_Align:
554            length = paint->measureText(text, bytesCount);
555            x -= length;
556            break;
557        default:
558            break;
559    }
560
561    int alpha;
562    SkXfermode::Mode mode;
563    getAlphaAndMode(paint, &alpha, &mode);
564
565    uint32_t color = paint->getColor();
566    const GLfloat a = alpha / 255.0f;
567    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
568    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
569    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
570
571    mModelView.loadIdentity();
572
573    GLuint textureUnit = 0;
574    // Needs to be set prior to calling FontRenderer::getTexture()
575    glActiveTexture(gTextureUnits[textureUnit]);
576
577    ProgramDescription description;
578    description.hasTexture = true;
579    description.hasAlpha8Texture = true;
580    if (mShader) {
581        mShader->describe(description, mExtensions);
582    }
583    if (mColorFilter) {
584        mColorFilter->describe(description, mExtensions);
585    }
586
587    useProgram(mProgramCache.get(description));
588    mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
589
590    // Text is always blended, no need to check the shader
591    chooseBlending(true, mode);
592    bindTexture(mFontRenderer.getTexture(), GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, textureUnit);
593    glUniform1i(mCurrentProgram->getUniform("sampler"), textureUnit);
594
595    int texCoordsSlot = mCurrentProgram->getAttrib("texCoords");
596    glEnableVertexAttribArray(texCoordsSlot);
597
598    // Always premultiplied
599    glUniform4f(mCurrentProgram->color, r, g, b, a);
600
601    textureUnit++;
602    // Setup attributes and uniforms required by the shaders
603    if (mShader) {
604        mShader->setupProgram(mCurrentProgram, mModelView, *mSnapshot, &textureUnit);
605    }
606    if (mColorFilter) {
607        mColorFilter->setupProgram(mCurrentProgram);
608    }
609
610    // TODO: Implement scale properly
611    const Rect& clip = mSnapshot->getLocalClip();
612    mFontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()), paint->getTextSize());
613    mFontRenderer.renderText(paint, &clip, text, 0, bytesCount, count, x, y);
614
615    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
616    glDisableVertexAttribArray(texCoordsSlot);
617}
618
619void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
620    GLuint textureUnit = 0;
621    glActiveTexture(gTextureUnits[textureUnit]);
622
623    const PathTexture* texture = mPathCache.get(path, paint);
624    if (!texture) return;
625    const AutoTexture autoCleanup(texture);
626
627    int alpha;
628    SkXfermode::Mode mode;
629    getAlphaAndMode(paint, &alpha, &mode);
630
631    uint32_t color = paint->getColor();
632    const GLfloat a = alpha / 255.0f;
633    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
634    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
635    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
636
637    // Describe the required shaders
638    ProgramDescription description;
639    description.hasTexture = true;
640    description.hasAlpha8Texture = true;
641    if (mShader) {
642        mShader->describe(description, mExtensions);
643    }
644    if (mColorFilter) {
645        mColorFilter->describe(description, mExtensions);
646    }
647
648    // Build and use the appropriate shader
649    useProgram(mProgramCache.get(description));
650
651    // Setup the blending mode
652    chooseBlending(true, mode);
653    bindTexture(texture->id, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, textureUnit);
654    glUniform1i(mCurrentProgram->getUniform("sampler"), textureUnit);
655
656    int texCoordsSlot = mCurrentProgram->getAttrib("texCoords");
657    glEnableVertexAttribArray(texCoordsSlot);
658
659    // Setup attributes
660    glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
661            gMeshStride, &mMeshVertices[0].position[0]);
662    glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE,
663            gMeshStride, &mMeshVertices[0].texture[0]);
664
665    // Setup uniforms
666    mModelView.loadTranslate(texture->left - texture->offset,
667            texture->top - texture->offset, 0.0f);
668    mModelView.scale(texture->width, texture->height, 1.0f);
669    mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
670
671    glUniform4f(mCurrentProgram->color, r, g, b, a);
672
673    textureUnit++;
674    // Setup attributes and uniforms required by the shaders
675    if (mShader) {
676        mShader->setupProgram(mCurrentProgram, mModelView, *mSnapshot, &textureUnit);
677    }
678    if (mColorFilter) {
679        mColorFilter->setupProgram(mCurrentProgram);
680    }
681
682    // Draw the mesh
683    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
684
685    glDisableVertexAttribArray(texCoordsSlot);
686}
687
688///////////////////////////////////////////////////////////////////////////////
689// Shaders
690///////////////////////////////////////////////////////////////////////////////
691
692void OpenGLRenderer::resetShader() {
693    mShader = NULL;
694}
695
696void OpenGLRenderer::setupShader(SkiaShader* shader) {
697    mShader = shader;
698    if (mShader) {
699        mShader->set(&mTextureCache, &mGradientCache);
700    }
701}
702
703///////////////////////////////////////////////////////////////////////////////
704// Color filters
705///////////////////////////////////////////////////////////////////////////////
706
707void OpenGLRenderer::resetColorFilter() {
708    mColorFilter = NULL;
709}
710
711void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
712    mColorFilter = filter;
713}
714
715///////////////////////////////////////////////////////////////////////////////
716// Drawing implementation
717///////////////////////////////////////////////////////////////////////////////
718
719void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
720        int color, SkXfermode::Mode mode, bool ignoreTransform) {
721    // If a shader is set, preserve only the alpha
722    if (mShader) {
723        color |= 0x00ffffff;
724    }
725
726    // Render using pre-multiplied alpha
727    const int alpha = (color >> 24) & 0xFF;
728    const GLfloat a = alpha / 255.0f;
729    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
730    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
731    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
732
733    GLuint textureUnit = 0;
734
735    // Setup the blending mode
736    chooseBlending(alpha < 255 || (mShader && mShader->blend()), mode);
737
738    // Describe the required shaders
739    ProgramDescription description;
740    if (mShader) {
741        mShader->describe(description, mExtensions);
742    }
743    if (mColorFilter) {
744        mColorFilter->describe(description, mExtensions);
745    }
746
747    // Build and use the appropriate shader
748    useProgram(mProgramCache.get(description));
749
750    // Setup attributes
751    glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
752            gMeshStride, &mMeshVertices[0].position[0]);
753
754    // Setup uniforms
755    mModelView.loadTranslate(left, top, 0.0f);
756    mModelView.scale(right - left, bottom - top, 1.0f);
757    if (!ignoreTransform) {
758        mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
759    } else {
760        mat4 identity;
761        mCurrentProgram->set(mOrthoMatrix, mModelView, identity);
762    }
763    glUniform4f(mCurrentProgram->color, r, g, b, a);
764
765    // Setup attributes and uniforms required by the shaders
766    if (mShader) {
767        mShader->setupProgram(mCurrentProgram, mModelView, *mSnapshot, &textureUnit);
768    }
769    if (mColorFilter) {
770        mColorFilter->setupProgram(mCurrentProgram);
771    }
772
773    // Draw the mesh
774    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
775}
776
777void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
778        const Texture* texture, const SkPaint* paint) {
779    int alpha;
780    SkXfermode::Mode mode;
781    getAlphaAndMode(paint, &alpha, &mode);
782
783    drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode, texture->blend,
784            &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0], NULL);
785}
786
787void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
788        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
789    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
790            &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0], NULL);
791}
792
793void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
794        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
795        GLvoid* vertices, GLvoid* texCoords, GLvoid* indices, GLsizei elementsCount) {
796    ProgramDescription description;
797    description.hasTexture = true;
798    if (mColorFilter) {
799        mColorFilter->describe(description, mExtensions);
800    }
801
802    mModelView.loadTranslate(left, top, 0.0f);
803    mModelView.scale(right - left, bottom - top, 1.0f);
804
805    useProgram(mProgramCache.get(description));
806    mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
807
808    chooseBlending(blend || alpha < 1.0f, mode);
809
810    // Texture
811    bindTexture(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, 0);
812    glUniform1i(mCurrentProgram->getUniform("sampler"), 0);
813
814    // Always premultiplied
815    glUniform4f(mCurrentProgram->color, alpha, alpha, alpha, alpha);
816
817    // Mesh
818    int texCoordsSlot = mCurrentProgram->getAttrib("texCoords");
819    glEnableVertexAttribArray(texCoordsSlot);
820    glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
821            gMeshStride, vertices);
822    glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
823
824    // Color filter
825    if (mColorFilter) {
826        mColorFilter->setupProgram(mCurrentProgram);
827    }
828
829    if (!indices) {
830        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
831    } else {
832        glDrawElements(GL_TRIANGLES, elementsCount, GL_UNSIGNED_SHORT, indices);
833    }
834    glDisableVertexAttribArray(texCoordsSlot);
835}
836
837void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode, bool isPremultiplied) {
838    blend = blend || mode != SkXfermode::kSrcOver_Mode;
839    if (blend) {
840        if (!mBlend) {
841            glEnable(GL_BLEND);
842        }
843
844        GLenum sourceMode = gBlends[mode].src;
845        GLenum destMode = gBlends[mode].dst;
846        if (!isPremultiplied && sourceMode == GL_ONE) {
847            sourceMode = GL_SRC_ALPHA;
848        }
849
850        if (sourceMode != mLastSrcMode || destMode != mLastDstMode) {
851            glBlendFunc(sourceMode, destMode);
852            mLastSrcMode = sourceMode;
853            mLastDstMode = destMode;
854        }
855    } else if (mBlend) {
856        glDisable(GL_BLEND);
857    }
858    mBlend = blend;
859}
860
861bool OpenGLRenderer::useProgram(Program* program) {
862    if (!program->isInUse()) {
863        if (mCurrentProgram != NULL) mCurrentProgram->remove();
864        program->use();
865        mCurrentProgram = program;
866        return false;
867    }
868    return true;
869}
870
871void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
872    TextureVertex* v = &mMeshVertices[0];
873    TextureVertex::setUV(v++, u1, v1);
874    TextureVertex::setUV(v++, u2, v1);
875    TextureVertex::setUV(v++, u1, v2);
876    TextureVertex::setUV(v++, u2, v2);
877}
878
879void OpenGLRenderer::getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
880    if (paint) {
881        const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
882        if (!isMode) {
883            // Assume SRC_OVER
884            *mode = SkXfermode::kSrcOver_Mode;
885        }
886
887        // Skia draws using the color's alpha channel if < 255
888        // Otherwise, it uses the paint's alpha
889        int color = paint->getColor();
890        *alpha = (color >> 24) & 0xFF;
891        if (*alpha == 255) {
892            *alpha = paint->getAlpha();
893        }
894    } else {
895        *mode = SkXfermode::kSrcOver_Mode;
896        *alpha = 255;
897    }
898}
899
900void OpenGLRenderer::bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit) {
901    glActiveTexture(gTextureUnits[textureUnit]);
902    glBindTexture(GL_TEXTURE_2D, texture);
903    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
904    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
905}
906
907}; // namespace uirenderer
908}; // namespace android
909