OpenGLRenderer.cpp revision 2542d199745cdf3ec910b8e3e4cff5851ed24e9b 
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#define DEFAULT_DROP_SHADOW_CACHE_SIZE 1.0f
45
46#define REQUIRED_TEXTURE_UNITS_COUNT 3
47
48// Converts a number of mega-bytes into bytes
49#define MB(s) s * 1024 * 1024
50
51// Generates simple and textured vertices
52#define FV(x, y, u, v) { { x, y }, { u, v } }
53
54///////////////////////////////////////////////////////////////////////////////
55// Globals
56///////////////////////////////////////////////////////////////////////////////
57
58// This array is never used directly but used as a memcpy source in the
59// OpenGLRenderer constructor
60static const TextureVertex gMeshVertices[] = {
61        FV(0.0f, 0.0f, 0.0f, 0.0f),
62        FV(1.0f, 0.0f, 1.0f, 0.0f),
63        FV(0.0f, 1.0f, 0.0f, 1.0f),
64        FV(1.0f, 1.0f, 1.0f, 1.0f)
65};
66static const GLsizei gMeshStride = sizeof(TextureVertex);
67static const GLsizei gMeshCount = 4;
68
69/**
70 * Structure mapping Skia xfermodes to OpenGL blending factors.
71 */
72struct Blender {
73    SkXfermode::Mode mode;
74    GLenum src;
75    GLenum dst;
76}; // struct Blender
77
78// In this array, the index of each Blender equals the value of the first
79// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
80static const Blender gBlends[] = {
81        { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
82        { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
83        { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
84        { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
85        { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
86        { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
87        { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
88        { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
89        { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
90        { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
91        { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
92        { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
93};
94
95static const GLenum gTextureUnits[] = {
96        GL_TEXTURE0,
97        GL_TEXTURE1,
98        GL_TEXTURE2
99};
100
101///////////////////////////////////////////////////////////////////////////////
102// Constructors/destructor
103///////////////////////////////////////////////////////////////////////////////
104
105OpenGLRenderer::OpenGLRenderer():
106        mBlend(false), mLastSrcMode(GL_ZERO), mLastDstMode(GL_ZERO),
107        mTextureCache(MB(DEFAULT_TEXTURE_CACHE_SIZE)),
108        mLayerCache(MB(DEFAULT_LAYER_CACHE_SIZE)),
109        mGradientCache(MB(DEFAULT_GRADIENT_CACHE_SIZE)),
110        mPathCache(MB(DEFAULT_PATH_CACHE_SIZE)),
111        mPatchCache(DEFAULT_PATCH_CACHE_SIZE),
112        mDropShadowCache(MB(DEFAULT_DROP_SHADOW_CACHE_SIZE)) {
113    LOGD("Create OpenGLRenderer");
114
115    char property[PROPERTY_VALUE_MAX];
116    if (property_get(PROPERTY_TEXTURE_CACHE_SIZE, property, NULL) > 0) {
117        LOGD("  Setting texture cache size to %sMB", property);
118        mTextureCache.setMaxSize(MB(atof(property)));
119    } else {
120        LOGD("  Using default texture cache size of %.2fMB", DEFAULT_TEXTURE_CACHE_SIZE);
121    }
122
123    if (property_get(PROPERTY_LAYER_CACHE_SIZE, property, NULL) > 0) {
124        LOGD("  Setting layer cache size to %sMB", property);
125        mLayerCache.setMaxSize(MB(atof(property)));
126    } else {
127        LOGD("  Using default layer cache size of %.2fMB", DEFAULT_LAYER_CACHE_SIZE);
128    }
129
130    if (property_get(PROPERTY_GRADIENT_CACHE_SIZE, property, NULL) > 0) {
131        LOGD("  Setting gradient cache size to %sMB", property);
132        mGradientCache.setMaxSize(MB(atof(property)));
133    } else {
134        LOGD("  Using default gradient cache size of %.2fMB", DEFAULT_GRADIENT_CACHE_SIZE);
135    }
136
137    if (property_get(PROPERTY_PATH_CACHE_SIZE, property, NULL) > 0) {
138        LOGD("  Setting path cache size to %sMB", property);
139        mPathCache.setMaxSize(MB(atof(property)));
140    } else {
141        LOGD("  Using default path cache size of %.2fMB", DEFAULT_PATH_CACHE_SIZE);
142    }
143
144    if (property_get(PROPERTY_DROP_SHADOW_CACHE_SIZE, property, NULL) > 0) {
145        LOGD("  Setting drop shadow cache size to %sMB", property);
146        mDropShadowCache.setMaxSize(MB(atof(property)));
147    } else {
148        LOGD("  Using default drop shadow cache size of %.2fMB", DEFAULT_DROP_SHADOW_CACHE_SIZE);
149    }
150    mDropShadowCache.setFontRenderer(mFontRenderer);
151
152    mCurrentProgram = NULL;
153    mShader = NULL;
154    mColorFilter = NULL;
155    mHasShadow = false;
156
157    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
158
159    mFirstSnapshot = new Snapshot;
160
161    GLint maxTextureUnits;
162    glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &maxTextureUnits);
163    if (maxTextureUnits < REQUIRED_TEXTURE_UNITS_COUNT) {
164        LOGW("At least %d texture units are required!", REQUIRED_TEXTURE_UNITS_COUNT);
165    }
166}
167
168OpenGLRenderer::~OpenGLRenderer() {
169    LOGD("Destroy OpenGLRenderer");
170
171    mTextureCache.clear();
172    mLayerCache.clear();
173    mGradientCache.clear();
174    mPathCache.clear();
175    mPatchCache.clear();
176    mProgramCache.clear();
177    mDropShadowCache.clear();
178}
179
180///////////////////////////////////////////////////////////////////////////////
181// Setup
182///////////////////////////////////////////////////////////////////////////////
183
184void OpenGLRenderer::setViewport(int width, int height) {
185    glViewport(0, 0, width, height);
186    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
187
188    mWidth = width;
189    mHeight = height;
190    mFirstSnapshot->height = height;
191    mFirstSnapshot->viewport.set(0, 0, width, height);
192}
193
194void OpenGLRenderer::prepare() {
195    mSnapshot = new Snapshot(mFirstSnapshot);
196    mSaveCount = 1;
197
198    glDisable(GL_SCISSOR_TEST);
199
200    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
201    glClear(GL_COLOR_BUFFER_BIT);
202
203    glEnable(GL_SCISSOR_TEST);
204    glScissor(0, 0, mWidth, mHeight);
205
206    mSnapshot->setClip(0.0f, 0.0f, mWidth, mHeight);
207}
208
209///////////////////////////////////////////////////////////////////////////////
210// State management
211///////////////////////////////////////////////////////////////////////////////
212
213int OpenGLRenderer::getSaveCount() const {
214    return mSaveCount;
215}
216
217int OpenGLRenderer::save(int flags) {
218    return saveSnapshot();
219}
220
221void OpenGLRenderer::restore() {
222    if (mSaveCount > 1) {
223        restoreSnapshot();
224    }
225}
226
227void OpenGLRenderer::restoreToCount(int saveCount) {
228    if (saveCount < 1) saveCount = 1;
229
230    while (mSaveCount > saveCount) {
231        restoreSnapshot();
232    }
233}
234
235int OpenGLRenderer::saveSnapshot() {
236    mSnapshot = new Snapshot(mSnapshot);
237    return mSaveCount++;
238}
239
240bool OpenGLRenderer::restoreSnapshot() {
241    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
242    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
243    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
244
245    sp<Snapshot> current = mSnapshot;
246    sp<Snapshot> previous = mSnapshot->previous;
247
248    if (restoreOrtho) {
249        Rect& r = previous->viewport;
250        glViewport(r.left, r.top, r.right, r.bottom);
251        mOrthoMatrix.load(current->orthoMatrix);
252    }
253
254    if (restoreLayer) {
255        composeLayer(current, previous);
256    }
257
258    bool skip = mSnapshot->skip;
259    if (!skip) {
260        mSaveCount--;
261    }
262    mSnapshot = previous;
263
264    if (restoreClip) {
265        setScissorFromClip();
266    }
267
268    return restoreClip;
269}
270
271///////////////////////////////////////////////////////////////////////////////
272// Layers
273///////////////////////////////////////////////////////////////////////////////
274
275int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
276        const SkPaint* p, int flags) {
277    int count = saveSnapshot();
278
279    int alpha = 255;
280    SkXfermode::Mode mode;
281
282    if (p) {
283        alpha = p->getAlpha();
284        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
285        if (!isMode) {
286            // Assume SRC_OVER
287            mode = SkXfermode::kSrcOver_Mode;
288        }
289    } else {
290        mode = SkXfermode::kSrcOver_Mode;
291    }
292
293    createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags);
294
295    return count;
296}
297
298int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
299        int alpha, int flags) {
300    int count = saveSnapshot();
301    createLayer(mSnapshot, left, top, right, bottom, alpha, SkXfermode::kSrcOver_Mode, flags);
302    return count;
303}
304
305bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
306        float right, float bottom, int alpha, SkXfermode::Mode mode,int flags) {
307    LAYER_LOGD("Requesting layer %fx%f", right - left, bottom - top);
308    LAYER_LOGD("Layer cache size = %d", mLayerCache.getSize());
309
310    GLuint previousFbo = snapshot->previous.get() ? snapshot->previous->fbo : 0;
311    LayerSize size(right - left, bottom - top);
312
313    Layer* layer = mLayerCache.get(size, previousFbo);
314    if (!layer) {
315        return false;
316    }
317
318    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
319
320    // Clear the FBO
321    glDisable(GL_SCISSOR_TEST);
322    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
323    glClear(GL_COLOR_BUFFER_BIT);
324    glEnable(GL_SCISSOR_TEST);
325
326    layer->mode = mode;
327    layer->alpha = alpha / 255.0f;
328    layer->layer.set(left, top, right, bottom);
329
330    // Save the layer in the snapshot
331    snapshot->flags |= Snapshot::kFlagIsLayer;
332    snapshot->layer = layer;
333    snapshot->fbo = layer->fbo;
334
335    snapshot->transform.loadTranslate(-left, -top, 0.0f);
336    snapshot->setClip(0.0f, 0.0f, right - left, bottom - top);
337    snapshot->viewport.set(0.0f, 0.0f, right - left, bottom - top);
338    snapshot->height = bottom - top;
339    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
340    snapshot->orthoMatrix.load(mOrthoMatrix);
341
342    setScissorFromClip();
343
344    // Change the ortho projection
345    glViewport(0, 0, right - left, bottom - top);
346    // Don't flip the FBO, it will get flipped when drawing back to the framebuffer
347    mOrthoMatrix.loadOrtho(0.0f, right - left, 0.0f, bottom - top, -1.0f, 1.0f);
348
349    return true;
350}
351
352void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
353    if (!current->layer) {
354        LOGE("Attempting to compose a layer that does not exist");
355        return;
356    }
357
358    // Unbind current FBO and restore previous one
359    // Most of the time, previous->fbo will be 0 to bind the default buffer
360    glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
361
362    // Restore the clip from the previous snapshot
363    const Rect& clip = previous->clipRect;
364    glScissor(clip.left, mHeight - clip.bottom, clip.getWidth(), clip.getHeight());
365
366    Layer* layer = current->layer;
367    const Rect& rect = layer->layer;
368
369    drawTextureRect(rect.left, rect.top, rect.right, rect.bottom,
370            layer->texture, layer->alpha, layer->mode, layer->blend);
371
372    LayerSize size(rect.getWidth(), rect.getHeight());
373    // Failing to add the layer to the cache should happen only if the
374    // layer is too large
375    if (!mLayerCache.put(size, layer)) {
376        LAYER_LOGD("Deleting layer");
377
378        glDeleteFramebuffers(1, &layer->fbo);
379        glDeleteTextures(1, &layer->texture);
380
381        delete layer;
382    }
383}
384
385///////////////////////////////////////////////////////////////////////////////
386// Transforms
387///////////////////////////////////////////////////////////////////////////////
388
389void OpenGLRenderer::translate(float dx, float dy) {
390    mSnapshot->transform.translate(dx, dy, 0.0f);
391}
392
393void OpenGLRenderer::rotate(float degrees) {
394    mSnapshot->transform.rotate(degrees, 0.0f, 0.0f, 1.0f);
395}
396
397void OpenGLRenderer::scale(float sx, float sy) {
398    mSnapshot->transform.scale(sx, sy, 1.0f);
399}
400
401void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
402    mSnapshot->transform.load(*matrix);
403}
404
405void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
406    mSnapshot->transform.copyTo(*matrix);
407}
408
409void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
410    mat4 m(*matrix);
411    mSnapshot->transform.multiply(m);
412}
413
414///////////////////////////////////////////////////////////////////////////////
415// Clipping
416///////////////////////////////////////////////////////////////////////////////
417
418void OpenGLRenderer::setScissorFromClip() {
419    const Rect& clip = mSnapshot->clipRect;
420    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
421}
422
423const Rect& OpenGLRenderer::getClipBounds() {
424    return mSnapshot->getLocalClip();
425}
426
427bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
428    Rect r(left, top, right, bottom);
429    mSnapshot->transform.mapRect(r);
430    return !mSnapshot->clipRect.intersects(r);
431}
432
433bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
434    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
435    if (clipped) {
436        setScissorFromClip();
437    }
438    return !mSnapshot->clipRect.isEmpty();
439}
440
441///////////////////////////////////////////////////////////////////////////////
442// Drawing
443///////////////////////////////////////////////////////////////////////////////
444
445void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, const SkPaint* paint) {
446    const float right = left + bitmap->width();
447    const float bottom = top + bitmap->height();
448
449    if (quickReject(left, top, right, bottom)) {
450        return;
451    }
452
453    glActiveTexture(GL_TEXTURE0);
454    const Texture* texture = mTextureCache.get(bitmap);
455    if (!texture) return;
456    const AutoTexture autoCleanup(texture);
457
458    drawTextureRect(left, top, right, bottom, texture, paint);
459}
460
461void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, const SkMatrix* matrix, const SkPaint* paint) {
462    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
463    const mat4 transform(*matrix);
464    transform.mapRect(r);
465
466    if (quickReject(r.left, r.top, r.right, r.bottom)) {
467        return;
468    }
469
470    glActiveTexture(GL_TEXTURE0);
471    const Texture* texture = mTextureCache.get(bitmap);
472    if (!texture) return;
473    const AutoTexture autoCleanup(texture);
474
475    drawTextureRect(r.left, r.top, r.right, r.bottom, texture, paint);
476}
477
478void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
479         float srcLeft, float srcTop, float srcRight, float srcBottom,
480         float dstLeft, float dstTop, float dstRight, float dstBottom,
481         const SkPaint* paint) {
482    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
483        return;
484    }
485
486    glActiveTexture(GL_TEXTURE0);
487    const Texture* texture = mTextureCache.get(bitmap);
488    if (!texture) return;
489    const AutoTexture autoCleanup(texture);
490
491    const float width = texture->width;
492    const float height = texture->height;
493
494    const float u1 = srcLeft / width;
495    const float v1 = srcTop / height;
496    const float u2 = srcRight / width;
497    const float v2 = srcBottom / height;
498
499    resetDrawTextureTexCoords(u1, v1, u2, v2);
500
501    drawTextureRect(dstLeft, dstTop, dstRight, dstBottom, texture, paint);
502
503    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
504}
505
506void OpenGLRenderer::drawPatch(SkBitmap* bitmap, Res_png_9patch* patch,
507        float left, float top, float right, float bottom, const SkPaint* paint) {
508    if (quickReject(left, top, right, bottom)) {
509        return;
510    }
511
512    glActiveTexture(GL_TEXTURE0);
513    const Texture* texture = mTextureCache.get(bitmap);
514    if (!texture) return;
515    const AutoTexture autoCleanup(texture);
516
517    int alpha;
518    SkXfermode::Mode mode;
519    getAlphaAndMode(paint, &alpha, &mode);
520
521    Patch* mesh = mPatchCache.get(patch);
522    mesh->updateVertices(bitmap, left, top, right, bottom,
523            &patch->xDivs[0], &patch->yDivs[0], patch->numXDivs, patch->numYDivs);
524
525    // Specify right and bottom as +1.0f from left/top to prevent scaling since the
526    // patch mesh already defines the final size
527    drawTextureMesh(left, top, left + 1.0f, top + 1.0f, texture->id, alpha / 255.0f,
528            mode, texture->blend, &mesh->vertices[0].position[0],
529            &mesh->vertices[0].texture[0], mesh->indices, mesh->indicesCount);
530}
531
532void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
533    const Rect& clip = mSnapshot->clipRect;
534    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
535}
536
537void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, const SkPaint* p) {
538    if (quickReject(left, top, right, bottom)) {
539        return;
540    }
541
542    SkXfermode::Mode mode;
543
544    const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
545    if (!isMode) {
546        // Assume SRC_OVER
547        mode = SkXfermode::kSrcOver_Mode;
548    }
549
550    // Skia draws using the color's alpha channel if < 255
551    // Otherwise, it uses the paint's alpha
552    int color = p->getColor();
553    if (((color >> 24) & 0xff) == 255) {
554        color |= p->getAlpha() << 24;
555    }
556
557    drawColorRect(left, top, right, bottom, color, mode);
558}
559
560void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
561        float x, float y, SkPaint* paint) {
562    if (text == NULL || count == 0 || (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
563        return;
564    }
565
566    float length = -1.0f;
567    switch (paint->getTextAlign()) {
568        case SkPaint::kCenter_Align:
569            length = paint->measureText(text, bytesCount);
570            x -= length / 2.0f;
571            break;
572        case SkPaint::kRight_Align:
573            length = paint->measureText(text, bytesCount);
574            x -= length;
575            break;
576        default:
577            break;
578    }
579
580    int alpha;
581    SkXfermode::Mode mode;
582    getAlphaAndMode(paint, &alpha, &mode);
583
584    uint32_t color = paint->getColor();
585    const GLfloat a = alpha / 255.0f;
586    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
587    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
588    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
589
590    mFontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()), paint->getTextSize());
591    if (mHasShadow) {
592        glActiveTexture(gTextureUnits[0]);
593        const ShadowTexture* shadow = mDropShadowCache.get(paint, text, bytesCount,
594                count, mShadowRadius);
595        const AutoTexture autoCleanup(shadow);
596
597        setupShadow(shadow, x, y, mode, a);
598
599        // Draw the mesh
600        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
601        glDisableVertexAttribArray(mCurrentProgram->getAttrib("texCoords"));
602    }
603
604    GLuint textureUnit = 0;
605    glActiveTexture(gTextureUnits[textureUnit]);
606
607    setupTextureAlpha8(mFontRenderer.getTexture(), 0, 0, textureUnit, x, y, r, g, b, a,
608            mode, false, true);
609
610    const Rect& clip = mSnapshot->getLocalClip();
611    mFontRenderer.renderText(paint, &clip, text, 0, bytesCount, count, x, y);
612
613    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
614    glDisableVertexAttribArray(mCurrentProgram->getAttrib("texCoords"));
615
616    drawTextDecorations(text, bytesCount, length, x, y, paint);
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    const float x = texture->left - texture->offset;
638    const float y = texture->top - texture->offset;
639
640    setupTextureAlpha8(texture, textureUnit, x, y, r, g, b, a, mode, true, true);
641
642    // Draw the mesh
643    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
644    glDisableVertexAttribArray(mCurrentProgram->getAttrib("texCoords"));
645}
646
647///////////////////////////////////////////////////////////////////////////////
648// Shaders
649///////////////////////////////////////////////////////////////////////////////
650
651void OpenGLRenderer::resetShader() {
652    mShader = NULL;
653}
654
655void OpenGLRenderer::setupShader(SkiaShader* shader) {
656    mShader = shader;
657    if (mShader) {
658        mShader->set(&mTextureCache, &mGradientCache);
659    }
660}
661
662///////////////////////////////////////////////////////////////////////////////
663// Color filters
664///////////////////////////////////////////////////////////////////////////////
665
666void OpenGLRenderer::resetColorFilter() {
667    mColorFilter = NULL;
668}
669
670void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
671    mColorFilter = filter;
672}
673
674///////////////////////////////////////////////////////////////////////////////
675// Drop shadow
676///////////////////////////////////////////////////////////////////////////////
677
678void OpenGLRenderer::resetShadow() {
679    mHasShadow = false;
680}
681
682void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
683    mHasShadow = true;
684    mShadowRadius = radius;
685    mShadowDx = dx;
686    mShadowDy = dy;
687    mShadowColor = color;
688}
689
690///////////////////////////////////////////////////////////////////////////////
691// Drawing implementation
692///////////////////////////////////////////////////////////////////////////////
693
694void OpenGLRenderer::setupShadow(const ShadowTexture* texture, float x, float y,
695        SkXfermode::Mode mode, float alpha) {
696    const float sx = x - texture->left + mShadowDx;
697    const float sy = y - texture->top + mShadowDy;
698
699    const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
700    const GLfloat a = shadowAlpha < 255 ? shadowAlpha / 255.0f : alpha;
701    const GLfloat r = a * ((mShadowColor >> 16) & 0xFF) / 255.0f;
702    const GLfloat g = a * ((mShadowColor >>  8) & 0xFF) / 255.0f;
703    const GLfloat b = a * ((mShadowColor      ) & 0xFF) / 255.0f;
704
705    GLuint textureUnit = 0;
706    setupTextureAlpha8(texture, textureUnit, sx, sy, r, g, b, a, mode, true, false);
707}
708
709void OpenGLRenderer::setupTextureAlpha8(const Texture* texture, GLuint& textureUnit,
710        float x, float y, float r, float g, float b, float a, SkXfermode::Mode mode,
711        bool transforms, bool applyFilters) {
712    setupTextureAlpha8(texture->id, texture->width, texture->height, textureUnit,
713            x, y, r, g, b, a, mode, transforms, applyFilters);
714}
715
716void OpenGLRenderer::setupTextureAlpha8(GLuint texture, uint32_t width, uint32_t height,
717        GLuint& textureUnit, float x, float y, float r, float g, float b, float a,
718        SkXfermode::Mode mode, bool transforms, bool applyFilters) {
719     // Describe the required shaders
720     ProgramDescription description;
721     description.hasTexture = true;
722     description.hasAlpha8Texture = true;
723
724     if (applyFilters) {
725         if (mShader) {
726             mShader->describe(description, mExtensions);
727         }
728         if (mColorFilter) {
729             mColorFilter->describe(description, mExtensions);
730         }
731     }
732
733     // Build and use the appropriate shader
734     useProgram(mProgramCache.get(description));
735
736     // Setup the blending mode
737     chooseBlending(true, mode);
738     bindTexture(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, textureUnit);
739     glUniform1i(mCurrentProgram->getUniform("sampler"), textureUnit);
740
741     int texCoordsSlot = mCurrentProgram->getAttrib("texCoords");
742     glEnableVertexAttribArray(texCoordsSlot);
743
744     // Setup attributes
745     glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
746             gMeshStride, &mMeshVertices[0].position[0]);
747     glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE,
748             gMeshStride, &mMeshVertices[0].texture[0]);
749
750     // Setup uniforms
751     if (transforms) {
752         mModelView.loadTranslate(x, y, 0.0f);
753         mModelView.scale(width, height, 1.0f);
754     } else {
755         mModelView.loadIdentity();
756     }
757     mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
758     glUniform4f(mCurrentProgram->color, r, g, b, a);
759
760     textureUnit++;
761     if (applyFilters) {
762         // Setup attributes and uniforms required by the shaders
763         if (mShader) {
764             mShader->setupProgram(mCurrentProgram, mModelView, *mSnapshot, &textureUnit);
765         }
766         if (mColorFilter) {
767             mColorFilter->setupProgram(mCurrentProgram);
768         }
769     }
770}
771
772#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
773#define kStdUnderline_Offset    (1.0f / 9.0f)
774#define kStdUnderline_Thickness (1.0f / 18.0f)
775
776void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
777        float x, float y, SkPaint* paint) {
778    // Handle underline and strike-through
779    uint32_t flags = paint->getFlags();
780    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
781        float underlineWidth = length;
782        // If length is > 0.0f, we already measured the text for the text alignment
783        if (length <= 0.0f) {
784            underlineWidth = paint->measureText(text, bytesCount);
785        }
786
787        float offsetX = 0;
788        switch (paint->getTextAlign()) {
789            case SkPaint::kCenter_Align:
790                offsetX = underlineWidth * 0.5f;
791                break;
792            case SkPaint::kRight_Align:
793                offsetX = underlineWidth;
794                break;
795            default:
796                break;
797        }
798
799        if (underlineWidth > 0.0f) {
800            float textSize = paint->getTextSize();
801            float height = textSize * kStdUnderline_Thickness;
802
803            float left = x - offsetX;
804            float top = 0.0f;
805            float right = left + underlineWidth;
806            float bottom = 0.0f;
807
808            if (flags & SkPaint::kUnderlineText_Flag) {
809                top = y + textSize * kStdUnderline_Offset;
810                bottom = top + height;
811                drawRect(left, top, right, bottom, paint);
812            }
813
814            if (flags & SkPaint::kStrikeThruText_Flag) {
815                top = y + textSize * kStdStrikeThru_Offset;
816                bottom = top + height;
817                drawRect(left, top, right, bottom, paint);
818            }
819        }
820    }
821}
822
823void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
824        int color, SkXfermode::Mode mode, bool ignoreTransform) {
825    // If a shader is set, preserve only the alpha
826    if (mShader) {
827        color |= 0x00ffffff;
828    }
829
830    // Render using pre-multiplied alpha
831    const int alpha = (color >> 24) & 0xFF;
832    const GLfloat a = alpha / 255.0f;
833    const GLfloat r = a * ((color >> 16) & 0xFF) / 255.0f;
834    const GLfloat g = a * ((color >>  8) & 0xFF) / 255.0f;
835    const GLfloat b = a * ((color      ) & 0xFF) / 255.0f;
836
837    GLuint textureUnit = 0;
838
839    // Setup the blending mode
840    chooseBlending(alpha < 255 || (mShader && mShader->blend()), mode);
841
842    // Describe the required shaders
843    ProgramDescription description;
844    if (mShader) {
845        mShader->describe(description, mExtensions);
846    }
847    if (mColorFilter) {
848        mColorFilter->describe(description, mExtensions);
849    }
850
851    // Build and use the appropriate shader
852    useProgram(mProgramCache.get(description));
853
854    // Setup attributes
855    glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
856            gMeshStride, &mMeshVertices[0].position[0]);
857
858    // Setup uniforms
859    mModelView.loadTranslate(left, top, 0.0f);
860    mModelView.scale(right - left, bottom - top, 1.0f);
861    if (!ignoreTransform) {
862        mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
863    } else {
864        mat4 identity;
865        mCurrentProgram->set(mOrthoMatrix, mModelView, identity);
866    }
867    glUniform4f(mCurrentProgram->color, r, g, b, a);
868
869    // Setup attributes and uniforms required by the shaders
870    if (mShader) {
871        mShader->setupProgram(mCurrentProgram, mModelView, *mSnapshot, &textureUnit);
872    }
873    if (mColorFilter) {
874        mColorFilter->setupProgram(mCurrentProgram);
875    }
876
877    // Draw the mesh
878    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
879}
880
881void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
882        const Texture* texture, const SkPaint* paint) {
883    int alpha;
884    SkXfermode::Mode mode;
885    getAlphaAndMode(paint, &alpha, &mode);
886
887    drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode, texture->blend,
888            &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0], NULL);
889}
890
891void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
892        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
893    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
894            &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0], NULL);
895}
896
897void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
898        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
899        GLvoid* vertices, GLvoid* texCoords, GLvoid* indices, GLsizei elementsCount) {
900    ProgramDescription description;
901    description.hasTexture = true;
902    if (mColorFilter) {
903        mColorFilter->describe(description, mExtensions);
904    }
905
906    mModelView.loadTranslate(left, top, 0.0f);
907    mModelView.scale(right - left, bottom - top, 1.0f);
908
909    useProgram(mProgramCache.get(description));
910    mCurrentProgram->set(mOrthoMatrix, mModelView, mSnapshot->transform);
911
912    chooseBlending(blend || alpha < 1.0f, mode);
913
914    // Texture
915    bindTexture(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, 0);
916    glUniform1i(mCurrentProgram->getUniform("sampler"), 0);
917
918    // Always premultiplied
919    glUniform4f(mCurrentProgram->color, alpha, alpha, alpha, alpha);
920
921    // Mesh
922    int texCoordsSlot = mCurrentProgram->getAttrib("texCoords");
923    glEnableVertexAttribArray(texCoordsSlot);
924    glVertexAttribPointer(mCurrentProgram->position, 2, GL_FLOAT, GL_FALSE,
925            gMeshStride, vertices);
926    glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
927
928    // Color filter
929    if (mColorFilter) {
930        mColorFilter->setupProgram(mCurrentProgram);
931    }
932
933    if (!indices) {
934        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
935    } else {
936        glDrawElements(GL_TRIANGLES, elementsCount, GL_UNSIGNED_SHORT, indices);
937    }
938    glDisableVertexAttribArray(texCoordsSlot);
939}
940
941void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode, bool isPremultiplied) {
942    blend = blend || mode != SkXfermode::kSrcOver_Mode;
943    if (blend) {
944        if (!mBlend) {
945            glEnable(GL_BLEND);
946        }
947
948        GLenum sourceMode = gBlends[mode].src;
949        GLenum destMode = gBlends[mode].dst;
950        if (!isPremultiplied && sourceMode == GL_ONE) {
951            sourceMode = GL_SRC_ALPHA;
952        }
953
954        if (sourceMode != mLastSrcMode || destMode != mLastDstMode) {
955            glBlendFunc(sourceMode, destMode);
956            mLastSrcMode = sourceMode;
957            mLastDstMode = destMode;
958        }
959    } else if (mBlend) {
960        glDisable(GL_BLEND);
961    }
962    mBlend = blend;
963}
964
965bool OpenGLRenderer::useProgram(Program* program) {
966    if (!program->isInUse()) {
967        if (mCurrentProgram != NULL) mCurrentProgram->remove();
968        program->use();
969        mCurrentProgram = program;
970        return false;
971    }
972    return true;
973}
974
975void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
976    TextureVertex* v = &mMeshVertices[0];
977    TextureVertex::setUV(v++, u1, v1);
978    TextureVertex::setUV(v++, u2, v1);
979    TextureVertex::setUV(v++, u1, v2);
980    TextureVertex::setUV(v++, u2, v2);
981}
982
983void OpenGLRenderer::getAlphaAndMode(const SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
984    if (paint) {
985        const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
986        if (!isMode) {
987            // Assume SRC_OVER
988            *mode = SkXfermode::kSrcOver_Mode;
989        }
990
991        // Skia draws using the color's alpha channel if < 255
992        // Otherwise, it uses the paint's alpha
993        int color = paint->getColor();
994        *alpha = (color >> 24) & 0xFF;
995        if (*alpha == 255) {
996            *alpha = paint->getAlpha();
997        }
998    } else {
999        *mode = SkXfermode::kSrcOver_Mode;
1000        *alpha = 255;
1001    }
1002}
1003
1004void OpenGLRenderer::bindTexture(GLuint texture, GLenum wrapS, GLenum wrapT, GLuint textureUnit) {
1005    glActiveTexture(gTextureUnits[textureUnit]);
1006    glBindTexture(GL_TEXTURE_2D, texture);
1007    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1008    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1009}
1010
1011}; // namespace uirenderer
1012}; // namespace android
1013