FontRenderer.cpp revision 00755fed35e4a91291c42a8a47bed8b957e9f8e1 
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 <SkUtils.h>
20
21#include <cutils/properties.h>
22
23#include <utils/Log.h>
24
25#include "Caches.h"
26#include "Debug.h"
27#include "FontRenderer.h"
28#include "Caches.h"
29
30namespace android {
31namespace uirenderer {
32
33///////////////////////////////////////////////////////////////////////////////
34// Defines
35///////////////////////////////////////////////////////////////////////////////
36
37#define DEFAULT_TEXT_CACHE_WIDTH 1024
38#define DEFAULT_TEXT_CACHE_HEIGHT 256
39#define MAX_TEXT_CACHE_WIDTH 2048
40#define TEXTURE_BORDER_SIZE 2
41
42#define AUTO_KERN(prev, next) (((next) - (prev) + 32) >> 6 << 16)
43
44///////////////////////////////////////////////////////////////////////////////
45// CacheTextureLine
46///////////////////////////////////////////////////////////////////////////////
47
48bool CacheTextureLine::fitBitmap(const SkGlyph& glyph, uint32_t *retOriginX, uint32_t *retOriginY) {
49    if (glyph.fHeight + TEXTURE_BORDER_SIZE > mMaxHeight) {
50        return false;
51    }
52
53    if (mCurrentCol + glyph.fWidth + TEXTURE_BORDER_SIZE < mMaxWidth) {
54        *retOriginX = mCurrentCol + 1;
55        *retOriginY = mCurrentRow + 1;
56        mCurrentCol += glyph.fWidth + TEXTURE_BORDER_SIZE;
57        mDirty = true;
58        return true;
59    }
60
61    return false;
62}
63
64///////////////////////////////////////////////////////////////////////////////
65// Font
66///////////////////////////////////////////////////////////////////////////////
67
68Font::Font(FontRenderer* state, uint32_t fontId, float fontSize,
69        int flags, uint32_t italicStyle, uint32_t scaleX,
70        SkPaint::Style style, uint32_t strokeWidth) :
71        mState(state), mFontId(fontId), mFontSize(fontSize),
72        mFlags(flags), mItalicStyle(italicStyle), mScaleX(scaleX),
73        mStyle(style), mStrokeWidth(mStrokeWidth) {
74}
75
76
77Font::~Font() {
78    for (uint32_t ct = 0; ct < mState->mActiveFonts.size(); ct++) {
79        if (mState->mActiveFonts[ct] == this) {
80            mState->mActiveFonts.removeAt(ct);
81            break;
82        }
83    }
84
85    for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) {
86        delete mCachedGlyphs.valueAt(i);
87    }
88}
89
90void Font::invalidateTextureCache(CacheTextureLine *cacheLine) {
91    for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) {
92        CachedGlyphInfo* cachedGlyph = mCachedGlyphs.valueAt(i);
93        if (cacheLine == NULL || cachedGlyph->mCachedTextureLine == cacheLine) {
94            cachedGlyph->mIsValid = false;
95        }
96    }
97}
98
99void Font::measureCachedGlyph(CachedGlyphInfo *glyph, int x, int y,
100        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
101    int nPenX = x + glyph->mBitmapLeft;
102    int nPenY = y + glyph->mBitmapTop;
103
104    int width = (int) glyph->mBitmapWidth;
105    int height = (int) glyph->mBitmapHeight;
106
107    if (bounds->bottom > nPenY) {
108        bounds->bottom = nPenY;
109    }
110    if (bounds->left > nPenX) {
111        bounds->left = nPenX;
112    }
113    if (bounds->right < nPenX + width) {
114        bounds->right = nPenX + width;
115    }
116    if (bounds->top < nPenY + height) {
117        bounds->top = nPenY + height;
118    }
119}
120
121void Font::drawCachedGlyph(CachedGlyphInfo* glyph, int x, int y,
122        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
123    int nPenX = x + glyph->mBitmapLeft;
124    int nPenY = y + glyph->mBitmapTop + glyph->mBitmapHeight;
125
126    float u1 = glyph->mBitmapMinU;
127    float u2 = glyph->mBitmapMaxU;
128    float v1 = glyph->mBitmapMinV;
129    float v2 = glyph->mBitmapMaxV;
130
131    int width = (int) glyph->mBitmapWidth;
132    int height = (int) glyph->mBitmapHeight;
133
134    mState->appendMeshQuad(nPenX, nPenY, u1, v2,
135            nPenX + width, nPenY, u2, v2,
136            nPenX + width, nPenY - height, u2, v1,
137            nPenX, nPenY - height, u1, v1, glyph->mCachedTextureLine->mCacheTexture);
138}
139
140void Font::drawCachedGlyphBitmap(CachedGlyphInfo* glyph, int x, int y,
141        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
142    int nPenX = x + glyph->mBitmapLeft;
143    int nPenY = y + glyph->mBitmapTop;
144
145    uint32_t endX = glyph->mStartX + glyph->mBitmapWidth;
146    uint32_t endY = glyph->mStartY + glyph->mBitmapHeight;
147
148    CacheTexture *cacheTexture = glyph->mCachedTextureLine->mCacheTexture;
149    uint32_t cacheWidth = cacheTexture->mWidth;
150    const uint8_t* cacheBuffer = cacheTexture->mTexture;
151
152    uint32_t cacheX = 0, cacheY = 0;
153    int32_t bX = 0, bY = 0;
154    for (cacheX = glyph->mStartX, bX = nPenX; cacheX < endX; cacheX++, bX++) {
155        for (cacheY = glyph->mStartY, bY = nPenY; cacheY < endY; cacheY++, bY++) {
156#if DEBUG_FONT_RENDERER
157            if (bX < 0 || bY < 0 || bX >= (int32_t) bitmapW || bY >= (int32_t) bitmapH) {
158                ALOGE("Skipping invalid index");
159                continue;
160            }
161#endif
162            uint8_t tempCol = cacheBuffer[cacheY * cacheWidth + cacheX];
163            bitmap[bY * bitmapW + bX] = tempCol;
164        }
165    }
166}
167
168void Font::drawCachedGlyph(CachedGlyphInfo* glyph, float x, float hOffset, float vOffset,
169        SkPathMeasure& measure, SkPoint* position, SkVector* tangent) {
170    const float halfWidth = glyph->mBitmapWidth * 0.5f;
171    const float height = glyph->mBitmapHeight;
172
173    vOffset += glyph->mBitmapTop + height;
174
175    SkPoint destination[4];
176    measure.getPosTan(x + hOffset +  glyph->mBitmapLeft + halfWidth, position, tangent);
177
178    // Move along the tangent and offset by the normal
179    destination[0].set(-tangent->fX * halfWidth - tangent->fY * vOffset,
180            -tangent->fY * halfWidth + tangent->fX * vOffset);
181    destination[1].set(tangent->fX * halfWidth - tangent->fY * vOffset,
182            tangent->fY * halfWidth + tangent->fX * vOffset);
183    destination[2].set(destination[1].fX + tangent->fY * height,
184            destination[1].fY - tangent->fX * height);
185    destination[3].set(destination[0].fX + tangent->fY * height,
186            destination[0].fY - tangent->fX * height);
187
188    const float u1 = glyph->mBitmapMinU;
189    const float u2 = glyph->mBitmapMaxU;
190    const float v1 = glyph->mBitmapMinV;
191    const float v2 = glyph->mBitmapMaxV;
192
193    mState->appendRotatedMeshQuad(
194            position->fX + destination[0].fX,
195            position->fY + destination[0].fY, u1, v2,
196            position->fX + destination[1].fX,
197            position->fY + destination[1].fY, u2, v2,
198            position->fX + destination[2].fX,
199            position->fY + destination[2].fY, u2, v1,
200            position->fX + destination[3].fX,
201            position->fY + destination[3].fY, u1, v1,
202            glyph->mCachedTextureLine->mCacheTexture);
203}
204
205CachedGlyphInfo* Font::getCachedGlyph(SkPaint* paint, glyph_t textUnit) {
206    CachedGlyphInfo* cachedGlyph = NULL;
207    ssize_t index = mCachedGlyphs.indexOfKey(textUnit);
208    if (index >= 0) {
209        cachedGlyph = mCachedGlyphs.valueAt(index);
210    } else {
211        cachedGlyph = cacheGlyph(paint, textUnit);
212    }
213
214    // Is the glyph still in texture cache?
215    if (!cachedGlyph->mIsValid) {
216        const SkGlyph& skiaGlyph = GET_METRICS(paint, textUnit);
217        updateGlyphCache(paint, skiaGlyph, cachedGlyph);
218    }
219
220    return cachedGlyph;
221}
222
223void Font::render(SkPaint* paint, const char* text, uint32_t start, uint32_t len,
224        int numGlyphs, int x, int y, uint8_t *bitmap, uint32_t bitmapW, uint32_t bitmapH) {
225    if (bitmap != NULL && bitmapW > 0 && bitmapH > 0) {
226        render(paint, text, start, len, numGlyphs, x, y, BITMAP, bitmap,
227                bitmapW, bitmapH, NULL, NULL);
228    } else {
229        render(paint, text, start, len, numGlyphs, x, y, FRAMEBUFFER, NULL,
230                0, 0, NULL, NULL);
231    }
232}
233
234void Font::render(SkPaint* paint, const char *text, uint32_t start, uint32_t len,
235            int numGlyphs, int x, int y, const float* positions) {
236    render(paint, text, start, len, numGlyphs, x, y, FRAMEBUFFER, NULL,
237            0, 0, NULL, positions);
238}
239
240void Font::render(SkPaint* paint, const char *text, uint32_t start, uint32_t len,
241        int numGlyphs, SkPath* path, float hOffset, float vOffset) {
242    if (numGlyphs == 0 || text == NULL || len == 0) {
243        return;
244    }
245
246    text += start;
247
248    int glyphsCount = 0;
249    SkFixed prevRsbDelta = 0;
250
251    float penX = 0.0f;
252
253    SkPoint position;
254    SkVector tangent;
255
256    SkPathMeasure measure(*path, false);
257    float pathLength = SkScalarToFloat(measure.getLength());
258
259    if (paint->getTextAlign() != SkPaint::kLeft_Align) {
260        float textWidth = SkScalarToFloat(paint->measureText(text, len));
261        float pathOffset = pathLength;
262        if (paint->getTextAlign() == SkPaint::kCenter_Align) {
263            textWidth *= 0.5f;
264            pathOffset *= 0.5f;
265        }
266        penX += pathOffset - textWidth;
267    }
268
269    while (glyphsCount < numGlyphs && penX < pathLength) {
270        glyph_t glyph = GET_GLYPH(text);
271
272        if (IS_END_OF_STRING(glyph)) {
273            break;
274        }
275
276        CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph);
277        penX += SkFixedToFloat(AUTO_KERN(prevRsbDelta, cachedGlyph->mLsbDelta));
278        prevRsbDelta = cachedGlyph->mRsbDelta;
279
280        if (cachedGlyph->mIsValid) {
281            drawCachedGlyph(cachedGlyph, penX, hOffset, vOffset, measure, &position, &tangent);
282        }
283
284        penX += SkFixedToFloat(cachedGlyph->mAdvanceX);
285
286        glyphsCount++;
287    }
288}
289
290void Font::measure(SkPaint* paint, const char* text, uint32_t start, uint32_t len,
291        int numGlyphs, Rect *bounds, const float* positions) {
292    if (bounds == NULL) {
293        ALOGE("No return rectangle provided to measure text");
294        return;
295    }
296    bounds->set(1e6, -1e6, -1e6, 1e6);
297    render(paint, text, start, len, numGlyphs, 0, 0, MEASURE, NULL, 0, 0, bounds, positions);
298}
299
300void Font::render(SkPaint* paint, const char* text, uint32_t start, uint32_t len,
301        int numGlyphs, int x, int y, RenderMode mode, uint8_t *bitmap,
302        uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* positions) {
303    if (numGlyphs == 0 || text == NULL || len == 0) {
304        return;
305    }
306
307    static RenderGlyph gRenderGlyph[] = {
308            &android::uirenderer::Font::drawCachedGlyph,
309            &android::uirenderer::Font::drawCachedGlyphBitmap,
310            &android::uirenderer::Font::measureCachedGlyph
311    };
312    RenderGlyph render = gRenderGlyph[mode];
313
314    text += start;
315    int glyphsCount = 0;
316
317    if (CC_LIKELY(positions == NULL)) {
318        SkFixed prevRsbDelta = 0;
319
320        float penX = x + 0.5f;
321        int penY = y;
322
323        while (glyphsCount < numGlyphs) {
324            glyph_t glyph = GET_GLYPH(text);
325
326            // Reached the end of the string
327            if (IS_END_OF_STRING(glyph)) {
328                break;
329            }
330
331            CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph);
332            penX += SkFixedToFloat(AUTO_KERN(prevRsbDelta, cachedGlyph->mLsbDelta));
333            prevRsbDelta = cachedGlyph->mRsbDelta;
334
335            // If it's still not valid, we couldn't cache it, so we shouldn't draw garbage
336            if (cachedGlyph->mIsValid) {
337                (*this.*render)(cachedGlyph, (int) floorf(penX), penY,
338                        bitmap, bitmapW, bitmapH, bounds, positions);
339            }
340
341            penX += SkFixedToFloat(cachedGlyph->mAdvanceX);
342
343            glyphsCount++;
344        }
345    } else {
346        const SkPaint::Align align = paint->getTextAlign();
347
348        // This is for renderPosText()
349        while (glyphsCount < numGlyphs) {
350            glyph_t glyph = GET_GLYPH(text);
351
352            // Reached the end of the string
353            if (IS_END_OF_STRING(glyph)) {
354                break;
355            }
356
357            CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph);
358
359            // If it's still not valid, we couldn't cache it, so we shouldn't draw garbage
360            if (cachedGlyph->mIsValid) {
361                int penX = x + positions[(glyphsCount << 1)];
362                int penY = y + positions[(glyphsCount << 1) + 1];
363
364                switch (align) {
365                    case SkPaint::kRight_Align:
366                        penX -= SkFixedToFloat(cachedGlyph->mAdvanceX);
367                        penY -= SkFixedToFloat(cachedGlyph->mAdvanceY);
368                        break;
369                    case SkPaint::kCenter_Align:
370                        penX -= SkFixedToFloat(cachedGlyph->mAdvanceX >> 1);
371                        penY -= SkFixedToFloat(cachedGlyph->mAdvanceY >> 1);
372                    default:
373                        break;
374                }
375
376                (*this.*render)(cachedGlyph, penX, penY,
377                        bitmap, bitmapW, bitmapH, bounds, positions);
378            }
379
380            glyphsCount++;
381        }
382    }
383}
384
385void Font::updateGlyphCache(SkPaint* paint, const SkGlyph& skiaGlyph, CachedGlyphInfo* glyph) {
386    glyph->mAdvanceX = skiaGlyph.fAdvanceX;
387    glyph->mAdvanceY = skiaGlyph.fAdvanceY;
388    glyph->mBitmapLeft = skiaGlyph.fLeft;
389    glyph->mBitmapTop = skiaGlyph.fTop;
390    glyph->mLsbDelta = skiaGlyph.fLsbDelta;
391    glyph->mRsbDelta = skiaGlyph.fRsbDelta;
392
393    uint32_t startX = 0;
394    uint32_t startY = 0;
395
396    // Get the bitmap for the glyph
397    paint->findImage(skiaGlyph);
398    mState->cacheBitmap(skiaGlyph, glyph, &startX, &startY);
399
400    if (!glyph->mIsValid) {
401        return;
402    }
403
404    uint32_t endX = startX + skiaGlyph.fWidth;
405    uint32_t endY = startY + skiaGlyph.fHeight;
406
407    glyph->mStartX = startX;
408    glyph->mStartY = startY;
409    glyph->mBitmapWidth = skiaGlyph.fWidth;
410    glyph->mBitmapHeight = skiaGlyph.fHeight;
411
412    uint32_t cacheWidth = glyph->mCachedTextureLine->mCacheTexture->mWidth;
413    uint32_t cacheHeight = glyph->mCachedTextureLine->mCacheTexture->mHeight;
414
415    glyph->mBitmapMinU = (float) startX / (float) cacheWidth;
416    glyph->mBitmapMinV = (float) startY / (float) cacheHeight;
417    glyph->mBitmapMaxU = (float) endX / (float) cacheWidth;
418    glyph->mBitmapMaxV = (float) endY / (float) cacheHeight;
419
420    mState->mUploadTexture = true;
421}
422
423CachedGlyphInfo* Font::cacheGlyph(SkPaint* paint, glyph_t glyph) {
424    CachedGlyphInfo* newGlyph = new CachedGlyphInfo();
425    mCachedGlyphs.add(glyph, newGlyph);
426
427    const SkGlyph& skiaGlyph = GET_METRICS(paint, glyph);
428    newGlyph->mGlyphIndex = skiaGlyph.fID;
429    newGlyph->mIsValid = false;
430
431    updateGlyphCache(paint, skiaGlyph, newGlyph);
432
433    return newGlyph;
434}
435
436Font* Font::create(FontRenderer* state, uint32_t fontId, float fontSize,
437        int flags, uint32_t italicStyle, uint32_t scaleX,
438        SkPaint::Style style, uint32_t strokeWidth) {
439    Vector<Font*> &activeFonts = state->mActiveFonts;
440
441    for (uint32_t i = 0; i < activeFonts.size(); i++) {
442        Font* font = activeFonts[i];
443        if (font->mFontId == fontId && font->mFontSize == fontSize &&
444                font->mFlags == flags && font->mItalicStyle == italicStyle &&
445                font->mScaleX == scaleX && font->mStyle == style &&
446                (style == SkPaint::kFill_Style || font->mStrokeWidth == strokeWidth)) {
447            return font;
448        }
449    }
450
451    Font* newFont = new Font(state, fontId, fontSize, flags, italicStyle,
452            scaleX, style, strokeWidth);
453    activeFonts.push(newFont);
454    return newFont;
455}
456
457///////////////////////////////////////////////////////////////////////////////
458// FontRenderer
459///////////////////////////////////////////////////////////////////////////////
460
461static bool sLogFontRendererCreate = true;
462
463FontRenderer::FontRenderer() {
464    if (sLogFontRendererCreate) {
465        INIT_LOGD("Creating FontRenderer");
466    }
467
468    mGammaTable = NULL;
469    mInitialized = false;
470    mMaxNumberOfQuads = 1024;
471    mCurrentQuadIndex = 0;
472
473    mTextMeshPtr = NULL;
474    mCurrentCacheTexture = NULL;
475    mLastCacheTexture = NULL;
476    mCacheTextureSmall = NULL;
477    mCacheTexture128 = NULL;
478    mCacheTexture256 = NULL;
479    mCacheTexture512 = NULL;
480
481    mLinearFiltering = false;
482
483    mIndexBufferID = 0;
484
485    mSmallCacheWidth = DEFAULT_TEXT_CACHE_WIDTH;
486    mSmallCacheHeight = DEFAULT_TEXT_CACHE_HEIGHT;
487
488    char property[PROPERTY_VALUE_MAX];
489    if (property_get(PROPERTY_TEXT_CACHE_WIDTH, property, NULL) > 0) {
490        if (sLogFontRendererCreate) {
491            INIT_LOGD("  Setting text cache width to %s pixels", property);
492        }
493        mSmallCacheWidth = atoi(property);
494    } else {
495        if (sLogFontRendererCreate) {
496            INIT_LOGD("  Using default text cache width of %i pixels", mSmallCacheWidth);
497        }
498    }
499
500    if (property_get(PROPERTY_TEXT_CACHE_HEIGHT, property, NULL) > 0) {
501        if (sLogFontRendererCreate) {
502            INIT_LOGD("  Setting text cache width to %s pixels", property);
503        }
504        mSmallCacheHeight = atoi(property);
505    } else {
506        if (sLogFontRendererCreate) {
507            INIT_LOGD("  Using default text cache height of %i pixels", mSmallCacheHeight);
508        }
509    }
510
511    sLogFontRendererCreate = false;
512}
513
514FontRenderer::~FontRenderer() {
515    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
516        delete mCacheLines[i];
517    }
518    mCacheLines.clear();
519
520    if (mInitialized) {
521        // Unbinding the buffer shouldn't be necessary but it crashes with some drivers
522        Caches::getInstance().unbindIndicesBuffer();
523        glDeleteBuffers(1, &mIndexBufferID);
524
525        delete[] mTextMeshPtr;
526        delete mCacheTextureSmall;
527        delete mCacheTexture128;
528        delete mCacheTexture256;
529        delete mCacheTexture512;
530    }
531
532    Vector<Font*> fontsToDereference = mActiveFonts;
533    for (uint32_t i = 0; i < fontsToDereference.size(); i++) {
534        delete fontsToDereference[i];
535    }
536}
537
538void FontRenderer::flushAllAndInvalidate() {
539    if (mCurrentQuadIndex != 0) {
540        issueDrawCommand();
541        mCurrentQuadIndex = 0;
542    }
543
544    for (uint32_t i = 0; i < mActiveFonts.size(); i++) {
545        mActiveFonts[i]->invalidateTextureCache();
546    }
547
548    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
549        mCacheLines[i]->mCurrentCol = 0;
550    }
551}
552
553void FontRenderer::deallocateTextureMemory(CacheTexture *cacheTexture) {
554    if (cacheTexture && cacheTexture->mTexture) {
555        glDeleteTextures(1, &cacheTexture->mTextureId);
556        delete[] cacheTexture->mTexture;
557        cacheTexture->mTexture = NULL;
558        cacheTexture->mTextureId = 0;
559    }
560}
561
562void FontRenderer::flushLargeCaches() {
563    if ((!mCacheTexture128 || !mCacheTexture128->mTexture) &&
564            (!mCacheTexture256 || !mCacheTexture256->mTexture) &&
565            (!mCacheTexture512 || !mCacheTexture512->mTexture)) {
566        // Typical case; no large glyph caches allocated
567        return;
568    }
569
570    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
571        CacheTextureLine* cacheLine = mCacheLines[i];
572        if ((cacheLine->mCacheTexture == mCacheTexture128 ||
573                cacheLine->mCacheTexture == mCacheTexture256 ||
574                cacheLine->mCacheTexture == mCacheTexture512) &&
575                cacheLine->mCacheTexture->mTexture != NULL) {
576            cacheLine->mCurrentCol = 0;
577            for (uint32_t i = 0; i < mActiveFonts.size(); i++) {
578                mActiveFonts[i]->invalidateTextureCache(cacheLine);
579            }
580        }
581    }
582
583    deallocateTextureMemory(mCacheTexture128);
584    deallocateTextureMemory(mCacheTexture256);
585    deallocateTextureMemory(mCacheTexture512);
586}
587
588void FontRenderer::allocateTextureMemory(CacheTexture* cacheTexture) {
589    int width = cacheTexture->mWidth;
590    int height = cacheTexture->mHeight;
591
592    cacheTexture->mTexture = new uint8_t[width * height];
593#if DEBUG_FONT_RENDERER
594    memset(cacheTexture->mTexture, 0, width * height * sizeof(uint8_t));
595#endif
596
597    if (!cacheTexture->mTextureId) {
598        glGenTextures(1, &cacheTexture->mTextureId);
599    }
600
601    Caches::getInstance().activeTexture(0);
602    glBindTexture(GL_TEXTURE_2D, cacheTexture->mTextureId);
603    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
604    // Initialize texture dimensions
605    glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, width, height, 0,
606            GL_ALPHA, GL_UNSIGNED_BYTE, 0);
607
608    const GLenum filtering = cacheTexture->mLinearFiltering ? GL_LINEAR : GL_NEAREST;
609    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filtering);
610    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filtering);
611
612    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
613    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
614}
615
616void FontRenderer::cacheBitmap(const SkGlyph& glyph, CachedGlyphInfo* cachedGlyph,
617        uint32_t* retOriginX, uint32_t* retOriginY) {
618    cachedGlyph->mIsValid = false;
619    // If the glyph is too tall, don't cache it
620    if (glyph.fHeight + TEXTURE_BORDER_SIZE > mCacheLines[mCacheLines.size() - 1]->mMaxHeight) {
621        ALOGE("Font size to large to fit in cache. width, height = %i, %i",
622                (int) glyph.fWidth, (int) glyph.fHeight);
623        return;
624    }
625
626    // Now copy the bitmap into the cache texture
627    uint32_t startX = 0;
628    uint32_t startY = 0;
629
630    bool bitmapFit = false;
631    CacheTextureLine *cacheLine;
632    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
633        bitmapFit = mCacheLines[i]->fitBitmap(glyph, &startX, &startY);
634        if (bitmapFit) {
635            cacheLine = mCacheLines[i];
636            break;
637        }
638    }
639
640    // If the new glyph didn't fit, flush the state so far and invalidate everything
641    if (!bitmapFit) {
642        flushAllAndInvalidate();
643
644        // Try to fit it again
645        for (uint32_t i = 0; i < mCacheLines.size(); i++) {
646            bitmapFit = mCacheLines[i]->fitBitmap(glyph, &startX, &startY);
647            if (bitmapFit) {
648                cacheLine = mCacheLines[i];
649                break;
650            }
651        }
652
653        // if we still don't fit, something is wrong and we shouldn't draw
654        if (!bitmapFit) {
655            return;
656        }
657    }
658
659    cachedGlyph->mCachedTextureLine = cacheLine;
660
661    *retOriginX = startX;
662    *retOriginY = startY;
663
664    uint32_t endX = startX + glyph.fWidth;
665    uint32_t endY = startY + glyph.fHeight;
666
667    uint32_t cacheWidth = cacheLine->mMaxWidth;
668
669    CacheTexture* cacheTexture = cacheLine->mCacheTexture;
670    if (!cacheTexture->mTexture) {
671        // Large-glyph texture memory is allocated only as needed
672        allocateTextureMemory(cacheTexture);
673    }
674
675    uint8_t* cacheBuffer = cacheTexture->mTexture;
676    uint8_t* bitmapBuffer = (uint8_t*) glyph.fImage;
677    unsigned int stride = glyph.rowBytes();
678
679    uint32_t cacheX = 0, bX = 0, cacheY = 0, bY = 0;
680    if (mGammaTable) {
681        for (cacheX = startX, bX = 0; cacheX < endX; cacheX++, bX++) {
682            for (cacheY = startY, bY = 0; cacheY < endY; cacheY++, bY++) {
683                uint8_t tempCol = bitmapBuffer[bY * stride + bX];
684                cacheBuffer[cacheY * cacheWidth + cacheX] = mGammaTable[tempCol];
685            }
686        }
687    } else {
688        for (cacheX = startX, bX = 0; cacheX < endX; cacheX++, bX++) {
689            for (cacheY = startY, bY = 0; cacheY < endY; cacheY++, bY++) {
690                uint8_t tempCol = bitmapBuffer[bY * stride + bX];
691                cacheBuffer[cacheY * cacheWidth + cacheX] = tempCol;
692            }
693        }
694    }
695
696    cachedGlyph->mIsValid = true;
697}
698
699CacheTexture* FontRenderer::createCacheTexture(int width, int height, bool allocate) {
700    CacheTexture* cacheTexture = new CacheTexture(width, height);
701
702    if (allocate) {
703        allocateTextureMemory(cacheTexture);
704    }
705
706    return cacheTexture;
707}
708
709void FontRenderer::initTextTexture() {
710    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
711        delete mCacheLines[i];
712    }
713    mCacheLines.clear();
714
715    if (mCacheTextureSmall) {
716        delete mCacheTextureSmall;
717        delete mCacheTexture128;
718        delete mCacheTexture256;
719        delete mCacheTexture512;
720    }
721
722    // Next, use other, separate caches for large glyphs.
723    uint16_t maxWidth = 0;
724    if (Caches::hasInstance()) {
725        maxWidth = Caches::getInstance().maxTextureSize;
726    }
727
728    if (maxWidth > MAX_TEXT_CACHE_WIDTH || maxWidth == 0) {
729        maxWidth = MAX_TEXT_CACHE_WIDTH;
730    }
731
732    mCacheTextureSmall = createCacheTexture(mSmallCacheWidth, mSmallCacheHeight, true);
733    mCacheTexture128 = createCacheTexture(maxWidth, 256, false);
734    mCacheTexture256 = createCacheTexture(maxWidth, 256, false);
735    mCacheTexture512 = createCacheTexture(maxWidth, 512, false);
736    mCurrentCacheTexture = mCacheTextureSmall;
737
738    mUploadTexture = false;
739    // Split up our default cache texture into lines of certain widths
740    int nextLine = 0;
741    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 18, nextLine, 0, mCacheTextureSmall));
742    nextLine += mCacheLines.top()->mMaxHeight;
743    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 26, nextLine, 0, mCacheTextureSmall));
744    nextLine += mCacheLines.top()->mMaxHeight;
745    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 26, nextLine, 0, mCacheTextureSmall));
746    nextLine += mCacheLines.top()->mMaxHeight;
747    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 34, nextLine, 0, mCacheTextureSmall));
748    nextLine += mCacheLines.top()->mMaxHeight;
749    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 34, nextLine, 0, mCacheTextureSmall));
750    nextLine += mCacheLines.top()->mMaxHeight;
751    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 42, nextLine, 0, mCacheTextureSmall));
752    nextLine += mCacheLines.top()->mMaxHeight;
753    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, mSmallCacheHeight - nextLine,
754            nextLine, 0, mCacheTextureSmall));
755
756    //  The first cache is split into 2 lines of height 128, the rest have just one cache line.
757    mCacheLines.push(new CacheTextureLine(maxWidth, 128, 0, 0, mCacheTexture128));
758    mCacheLines.push(new CacheTextureLine(maxWidth, 128, 128, 0, mCacheTexture128));
759    mCacheLines.push(new CacheTextureLine(maxWidth, 256, 0, 0, mCacheTexture256));
760    mCacheLines.push(new CacheTextureLine(maxWidth, 512, 0, 0, mCacheTexture512));
761}
762
763// Avoid having to reallocate memory and render quad by quad
764void FontRenderer::initVertexArrayBuffers() {
765    uint32_t numIndices = mMaxNumberOfQuads * 6;
766    uint32_t indexBufferSizeBytes = numIndices * sizeof(uint16_t);
767    uint16_t* indexBufferData = (uint16_t*) malloc(indexBufferSizeBytes);
768
769    // Four verts, two triangles , six indices per quad
770    for (uint32_t i = 0; i < mMaxNumberOfQuads; i++) {
771        int i6 = i * 6;
772        int i4 = i * 4;
773
774        indexBufferData[i6 + 0] = i4 + 0;
775        indexBufferData[i6 + 1] = i4 + 1;
776        indexBufferData[i6 + 2] = i4 + 2;
777
778        indexBufferData[i6 + 3] = i4 + 0;
779        indexBufferData[i6 + 4] = i4 + 2;
780        indexBufferData[i6 + 5] = i4 + 3;
781    }
782
783    glGenBuffers(1, &mIndexBufferID);
784    Caches::getInstance().bindIndicesBuffer(mIndexBufferID);
785    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexBufferSizeBytes, indexBufferData, GL_STATIC_DRAW);
786
787    free(indexBufferData);
788
789    uint32_t coordSize = 2;
790    uint32_t uvSize = 2;
791    uint32_t vertsPerQuad = 4;
792    uint32_t vertexBufferSize = mMaxNumberOfQuads * vertsPerQuad * coordSize * uvSize;
793    mTextMeshPtr = new float[vertexBufferSize];
794}
795
796// We don't want to allocate anything unless we actually draw text
797void FontRenderer::checkInit() {
798    if (mInitialized) {
799        return;
800    }
801
802    initTextTexture();
803    initVertexArrayBuffers();
804
805    mInitialized = true;
806}
807
808void FontRenderer::checkTextureUpdate() {
809    if (!mUploadTexture && mLastCacheTexture == mCurrentCacheTexture) {
810        return;
811    }
812
813    Caches& caches = Caches::getInstance();
814    GLuint lastTextureId = 0;
815    // Iterate over all the cache lines and see which ones need to be updated
816    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
817        CacheTextureLine* cl = mCacheLines[i];
818        if (cl->mDirty && cl->mCacheTexture->mTexture != NULL) {
819            CacheTexture* cacheTexture = cl->mCacheTexture;
820            uint32_t xOffset = 0;
821            uint32_t yOffset = cl->mCurrentRow;
822            uint32_t width   = cl->mMaxWidth;
823            uint32_t height  = cl->mMaxHeight;
824            void* textureData = cacheTexture->mTexture + (yOffset * width);
825
826            if (cacheTexture->mTextureId != lastTextureId) {
827                caches.activeTexture(0);
828                glBindTexture(GL_TEXTURE_2D, cacheTexture->mTextureId);
829                lastTextureId = cacheTexture->mTextureId;
830            }
831            glTexSubImage2D(GL_TEXTURE_2D, 0, xOffset, yOffset, width, height,
832                    GL_ALPHA, GL_UNSIGNED_BYTE, textureData);
833
834            cl->mDirty = false;
835        }
836    }
837
838    caches.activeTexture(0);
839    glBindTexture(GL_TEXTURE_2D, mCurrentCacheTexture->mTextureId);
840    if (mLinearFiltering != mCurrentCacheTexture->mLinearFiltering) {
841        const GLenum filtering = mLinearFiltering ? GL_LINEAR : GL_NEAREST;
842        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filtering);
843        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filtering);
844        mCurrentCacheTexture->mLinearFiltering = mLinearFiltering;
845    }
846    mLastCacheTexture = mCurrentCacheTexture;
847
848    mUploadTexture = false;
849}
850
851void FontRenderer::issueDrawCommand() {
852    checkTextureUpdate();
853
854    Caches& caches = Caches::getInstance();
855    caches.bindIndicesBuffer(mIndexBufferID);
856    if (!mDrawn) {
857        float* buffer = mTextMeshPtr;
858        int offset = 2;
859
860        bool force = caches.unbindMeshBuffer();
861        caches.bindPositionVertexPointer(force, caches.currentProgram->position, buffer);
862        caches.bindTexCoordsVertexPointer(force, caches.currentProgram->texCoords,
863                buffer + offset);
864    }
865
866    glDrawElements(GL_TRIANGLES, mCurrentQuadIndex * 6, GL_UNSIGNED_SHORT, NULL);
867
868    mDrawn = true;
869}
870
871void FontRenderer::appendMeshQuadNoClip(float x1, float y1, float u1, float v1,
872        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
873        float x4, float y4, float u4, float v4, CacheTexture* texture) {
874    if (texture != mCurrentCacheTexture) {
875        if (mCurrentQuadIndex != 0) {
876            // First, draw everything stored already which uses the previous texture
877            issueDrawCommand();
878            mCurrentQuadIndex = 0;
879        }
880        // Now use the new texture id
881        mCurrentCacheTexture = texture;
882    }
883
884    const uint32_t vertsPerQuad = 4;
885    const uint32_t floatsPerVert = 4;
886    float* currentPos = mTextMeshPtr + mCurrentQuadIndex * vertsPerQuad * floatsPerVert;
887
888    (*currentPos++) = x1;
889    (*currentPos++) = y1;
890    (*currentPos++) = u1;
891    (*currentPos++) = v1;
892
893    (*currentPos++) = x2;
894    (*currentPos++) = y2;
895    (*currentPos++) = u2;
896    (*currentPos++) = v2;
897
898    (*currentPos++) = x3;
899    (*currentPos++) = y3;
900    (*currentPos++) = u3;
901    (*currentPos++) = v3;
902
903    (*currentPos++) = x4;
904    (*currentPos++) = y4;
905    (*currentPos++) = u4;
906    (*currentPos++) = v4;
907
908    mCurrentQuadIndex++;
909}
910
911void FontRenderer::appendMeshQuad(float x1, float y1, float u1, float v1,
912        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
913        float x4, float y4, float u4, float v4, CacheTexture* texture) {
914
915    if (mClip &&
916            (x1 > mClip->right || y1 < mClip->top || x2 < mClip->left || y4 > mClip->bottom)) {
917        return;
918    }
919
920    appendMeshQuadNoClip(x1, y1, u1, v1, x2, y2, u2, v2, x3, y3, u3, v3, x4, y4, u4, v4, texture);
921
922    if (mBounds) {
923        mBounds->left = fmin(mBounds->left, x1);
924        mBounds->top = fmin(mBounds->top, y3);
925        mBounds->right = fmax(mBounds->right, x3);
926        mBounds->bottom = fmax(mBounds->bottom, y1);
927    }
928
929    if (mCurrentQuadIndex == mMaxNumberOfQuads) {
930        issueDrawCommand();
931        mCurrentQuadIndex = 0;
932    }
933}
934
935void FontRenderer::appendRotatedMeshQuad(float x1, float y1, float u1, float v1,
936        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
937        float x4, float y4, float u4, float v4, CacheTexture* texture) {
938
939    appendMeshQuadNoClip(x1, y1, u1, v1, x2, y2, u2, v2, x3, y3, u3, v3, x4, y4, u4, v4, texture);
940
941    if (mBounds) {
942        mBounds->left = fmin(mBounds->left, fmin(x1, fmin(x2, fmin(x3, x4))));
943        mBounds->top = fmin(mBounds->top, fmin(y1, fmin(y2, fmin(y3, y4))));
944        mBounds->right = fmax(mBounds->right, fmax(x1, fmax(x2, fmax(x3, x4))));
945        mBounds->bottom = fmax(mBounds->bottom, fmax(y1, fmax(y2, fmax(y3, y4))));
946    }
947
948    if (mCurrentQuadIndex == mMaxNumberOfQuads) {
949        issueDrawCommand();
950        mCurrentQuadIndex = 0;
951    }
952}
953
954uint32_t FontRenderer::getRemainingCacheCapacity() {
955    uint32_t remainingCapacity = 0;
956    float totalPixels = 0;
957    for(uint32_t i = 0; i < mCacheLines.size(); i ++) {
958         remainingCapacity += (mCacheLines[i]->mMaxWidth - mCacheLines[i]->mCurrentCol);
959         totalPixels += mCacheLines[i]->mMaxWidth;
960    }
961    remainingCapacity = (remainingCapacity * 100) / totalPixels;
962    return remainingCapacity;
963}
964
965void FontRenderer::precacheLatin(SkPaint* paint) {
966    // Remaining capacity is measured in %
967    uint32_t remainingCapacity = getRemainingCacheCapacity();
968    uint32_t precacheIndex = 0;
969
970    // We store a string with letters in a rough frequency of occurrence
971    String16 l("eisarntolcdugpmhbyfvkwzxjq EISARNTOLCDUGPMHBYFVKWZXJQ,.?!()-+@;:'0123456789");
972
973    size_t size = l.size();
974    uint16_t latin[size];
975    paint->utfToGlyphs(l.string(), SkPaint::kUTF16_TextEncoding, size * sizeof(char16_t), latin);
976
977    while (remainingCapacity > 25 && precacheIndex < size) {
978        mCurrentFont->getCachedGlyph(paint, TO_GLYPH(latin[precacheIndex]));
979        remainingCapacity = getRemainingCacheCapacity();
980        precacheIndex++;
981    }
982}
983
984void FontRenderer::setFont(SkPaint* paint, uint32_t fontId, float fontSize) {
985    uint32_t currentNumFonts = mActiveFonts.size();
986    int flags = 0;
987    if (paint->isFakeBoldText()) {
988        flags |= Font::kFakeBold;
989    }
990
991    const float skewX = paint->getTextSkewX();
992    uint32_t italicStyle = *(uint32_t*) &skewX;
993    const float scaleXFloat = paint->getTextScaleX();
994    uint32_t scaleX = *(uint32_t*) &scaleXFloat;
995    SkPaint::Style style = paint->getStyle();
996    const float strokeWidthFloat = paint->getStrokeWidth();
997    uint32_t strokeWidth = *(uint32_t*) &strokeWidthFloat;
998    mCurrentFont = Font::create(this, fontId, fontSize, flags, italicStyle,
999            scaleX, style, strokeWidth);
1000
1001    const float maxPrecacheFontSize = 40.0f;
1002    bool isNewFont = currentNumFonts != mActiveFonts.size();
1003
1004    if (isNewFont && fontSize <= maxPrecacheFontSize) {
1005        precacheLatin(paint);
1006    }
1007}
1008
1009FontRenderer::DropShadow FontRenderer::renderDropShadow(SkPaint* paint, const char *text,
1010        uint32_t startIndex, uint32_t len, int numGlyphs, uint32_t radius, const float* positions) {
1011    checkInit();
1012
1013    if (!mCurrentFont) {
1014        DropShadow image;
1015        image.width = 0;
1016        image.height = 0;
1017        image.image = NULL;
1018        image.penX = 0;
1019        image.penY = 0;
1020        return image;
1021    }
1022
1023    mDrawn = false;
1024    mClip = NULL;
1025    mBounds = NULL;
1026
1027    Rect bounds;
1028    mCurrentFont->measure(paint, text, startIndex, len, numGlyphs, &bounds, positions);
1029
1030    uint32_t paddedWidth = (uint32_t) (bounds.right - bounds.left) + 2 * radius;
1031    uint32_t paddedHeight = (uint32_t) (bounds.top - bounds.bottom) + 2 * radius;
1032    uint8_t* dataBuffer = new uint8_t[paddedWidth * paddedHeight];
1033
1034    for (uint32_t i = 0; i < paddedWidth * paddedHeight; i++) {
1035        dataBuffer[i] = 0;
1036    }
1037
1038    int penX = radius - bounds.left;
1039    int penY = radius - bounds.bottom;
1040
1041    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, penX, penY,
1042            Font::BITMAP, dataBuffer, paddedWidth, paddedHeight, NULL, positions);
1043    blurImage(dataBuffer, paddedWidth, paddedHeight, radius);
1044
1045    DropShadow image;
1046    image.width = paddedWidth;
1047    image.height = paddedHeight;
1048    image.image = dataBuffer;
1049    image.penX = penX;
1050    image.penY = penY;
1051
1052    return image;
1053}
1054
1055void FontRenderer::initRender(const Rect* clip, Rect* bounds) {
1056    checkInit();
1057
1058    mDrawn = false;
1059    mBounds = bounds;
1060    mClip = clip;
1061}
1062
1063void FontRenderer::finishRender() {
1064    mBounds = NULL;
1065    mClip = NULL;
1066
1067    if (mCurrentQuadIndex != 0) {
1068        issueDrawCommand();
1069        mCurrentQuadIndex = 0;
1070    }
1071}
1072
1073bool FontRenderer::renderText(SkPaint* paint, const Rect* clip, const char *text,
1074        uint32_t startIndex, uint32_t len, int numGlyphs, int x, int y, Rect* bounds) {
1075    if (!mCurrentFont) {
1076        ALOGE("No font set");
1077        return false;
1078    }
1079
1080    initRender(clip, bounds);
1081    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, x, y);
1082    finishRender();
1083
1084    return mDrawn;
1085}
1086
1087bool FontRenderer::renderPosText(SkPaint* paint, const Rect* clip, const char *text,
1088        uint32_t startIndex, uint32_t len, int numGlyphs, int x, int y,
1089        const float* positions, Rect* bounds) {
1090    if (!mCurrentFont) {
1091        ALOGE("No font set");
1092        return false;
1093    }
1094
1095    initRender(clip, bounds);
1096    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, x, y, positions);
1097    finishRender();
1098
1099    return mDrawn;
1100}
1101
1102bool FontRenderer::renderTextOnPath(SkPaint* paint, const Rect* clip, const char *text,
1103        uint32_t startIndex, uint32_t len, int numGlyphs, SkPath* path,
1104        float hOffset, float vOffset, Rect* bounds) {
1105    if (!mCurrentFont) {
1106        ALOGE("No font set");
1107        return false;
1108    }
1109
1110    initRender(clip, bounds);
1111    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, path, hOffset, vOffset);
1112    finishRender();
1113
1114    return mDrawn;
1115}
1116
1117void FontRenderer::computeGaussianWeights(float* weights, int32_t radius) {
1118    // Compute gaussian weights for the blur
1119    // e is the euler's number
1120    float e = 2.718281828459045f;
1121    float pi = 3.1415926535897932f;
1122    // g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 )
1123    // x is of the form [-radius .. 0 .. radius]
1124    // and sigma varies with radius.
1125    // Based on some experimental radius values and sigma's
1126    // we approximately fit sigma = f(radius) as
1127    // sigma = radius * 0.3  + 0.6
1128    // The larger the radius gets, the more our gaussian blur
1129    // will resemble a box blur since with large sigma
1130    // the gaussian curve begins to lose its shape
1131    float sigma = 0.3f * (float) radius + 0.6f;
1132
1133    // Now compute the coefficints
1134    // We will store some redundant values to save some math during
1135    // the blur calculations
1136    // precompute some values
1137    float coeff1 = 1.0f / (sqrt( 2.0f * pi ) * sigma);
1138    float coeff2 = - 1.0f / (2.0f * sigma * sigma);
1139
1140    float normalizeFactor = 0.0f;
1141    for (int32_t r = -radius; r <= radius; r ++) {
1142        float floatR = (float) r;
1143        weights[r + radius] = coeff1 * pow(e, floatR * floatR * coeff2);
1144        normalizeFactor += weights[r + radius];
1145    }
1146
1147    //Now we need to normalize the weights because all our coefficients need to add up to one
1148    normalizeFactor = 1.0f / normalizeFactor;
1149    for (int32_t r = -radius; r <= radius; r ++) {
1150        weights[r + radius] *= normalizeFactor;
1151    }
1152}
1153
1154void FontRenderer::horizontalBlur(float* weights, int32_t radius,
1155        const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
1156    float blurredPixel = 0.0f;
1157    float currentPixel = 0.0f;
1158
1159    for (int32_t y = 0; y < height; y ++) {
1160
1161        const uint8_t* input = source + y * width;
1162        uint8_t* output = dest + y * width;
1163
1164        for (int32_t x = 0; x < width; x ++) {
1165            blurredPixel = 0.0f;
1166            const float* gPtr = weights;
1167            // Optimization for non-border pixels
1168            if (x > radius && x < (width - radius)) {
1169                const uint8_t *i = input + (x - radius);
1170                for (int r = -radius; r <= radius; r ++) {
1171                    currentPixel = (float) (*i);
1172                    blurredPixel += currentPixel * gPtr[0];
1173                    gPtr++;
1174                    i++;
1175                }
1176            } else {
1177                for (int32_t r = -radius; r <= radius; r ++) {
1178                    // Stepping left and right away from the pixel
1179                    int validW = x + r;
1180                    if (validW < 0) {
1181                        validW = 0;
1182                    }
1183                    if (validW > width - 1) {
1184                        validW = width - 1;
1185                    }
1186
1187                    currentPixel = (float) input[validW];
1188                    blurredPixel += currentPixel * gPtr[0];
1189                    gPtr++;
1190                }
1191            }
1192            *output = (uint8_t)blurredPixel;
1193            output ++;
1194        }
1195    }
1196}
1197
1198void FontRenderer::verticalBlur(float* weights, int32_t radius,
1199        const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
1200    float blurredPixel = 0.0f;
1201    float currentPixel = 0.0f;
1202
1203    for (int32_t y = 0; y < height; y ++) {
1204
1205        uint8_t* output = dest + y * width;
1206
1207        for (int32_t x = 0; x < width; x ++) {
1208            blurredPixel = 0.0f;
1209            const float* gPtr = weights;
1210            const uint8_t* input = source + x;
1211            // Optimization for non-border pixels
1212            if (y > radius && y < (height - radius)) {
1213                const uint8_t *i = input + ((y - radius) * width);
1214                for (int32_t r = -radius; r <= radius; r ++) {
1215                    currentPixel = (float)(*i);
1216                    blurredPixel += currentPixel * gPtr[0];
1217                    gPtr++;
1218                    i += width;
1219                }
1220            } else {
1221                for (int32_t r = -radius; r <= radius; r ++) {
1222                    int validH = y + r;
1223                    // Clamp to zero and width
1224                    if (validH < 0) {
1225                        validH = 0;
1226                    }
1227                    if (validH > height - 1) {
1228                        validH = height - 1;
1229                    }
1230
1231                    const uint8_t *i = input + validH * width;
1232                    currentPixel = (float) (*i);
1233                    blurredPixel += currentPixel * gPtr[0];
1234                    gPtr++;
1235                }
1236            }
1237            *output = (uint8_t) blurredPixel;
1238            output ++;
1239        }
1240    }
1241}
1242
1243
1244void FontRenderer::blurImage(uint8_t *image, int32_t width, int32_t height, int32_t radius) {
1245    float *gaussian = new float[2 * radius + 1];
1246    computeGaussianWeights(gaussian, radius);
1247
1248    uint8_t* scratch = new uint8_t[width * height];
1249
1250    horizontalBlur(gaussian, radius, image, scratch, width, height);
1251    verticalBlur(gaussian, radius, scratch, image, width, height);
1252
1253    delete[] gaussian;
1254    delete[] scratch;
1255}
1256
1257}; // namespace uirenderer
1258}; // namespace android
1259