FontRenderer.cpp revision 0412cfcbcdd7224f80a80180a946f0fdd28c3afc 
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) {
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, NULL);
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    for (cacheX = startX, bX = 0; cacheX < endX; cacheX++, bX++) {
681        for (cacheY = startY, bY = 0; cacheY < endY; cacheY++, bY++) {
682            uint8_t tempCol = bitmapBuffer[bY * stride + bX];
683            cacheBuffer[cacheY * cacheWidth + cacheX] = mGammaTable[tempCol];
684        }
685    }
686
687    cachedGlyph->mIsValid = true;
688}
689
690CacheTexture* FontRenderer::createCacheTexture(int width, int height, bool allocate) {
691    uint8_t* textureMemory = NULL;
692    CacheTexture* cacheTexture = new CacheTexture(textureMemory, width, height);
693
694    if (allocate) {
695        allocateTextureMemory(cacheTexture);
696    }
697
698    return cacheTexture;
699}
700
701void FontRenderer::initTextTexture() {
702    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
703        delete mCacheLines[i];
704    }
705    mCacheLines.clear();
706
707    if (mCacheTextureSmall) {
708        delete mCacheTextureSmall;
709        delete mCacheTexture128;
710        delete mCacheTexture256;
711        delete mCacheTexture512;
712    }
713
714    // Next, use other, separate caches for large glyphs.
715    uint16_t maxWidth = 0;
716    if (Caches::hasInstance()) {
717        maxWidth = Caches::getInstance().maxTextureSize;
718    }
719
720    if (maxWidth > MAX_TEXT_CACHE_WIDTH || maxWidth == 0) {
721        maxWidth = MAX_TEXT_CACHE_WIDTH;
722    }
723
724    mCacheTextureSmall = createCacheTexture(mSmallCacheWidth, mSmallCacheHeight, true);
725    mCacheTexture128 = createCacheTexture(maxWidth, 256, false);
726    mCacheTexture256 = createCacheTexture(maxWidth, 256, false);
727    mCacheTexture512 = createCacheTexture(maxWidth, 512, false);
728    mCurrentCacheTexture = mCacheTextureSmall;
729
730    mUploadTexture = false;
731    // Split up our default cache texture into lines of certain widths
732    int nextLine = 0;
733    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 18, nextLine, 0, mCacheTextureSmall));
734    nextLine += mCacheLines.top()->mMaxHeight;
735    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 26, nextLine, 0, mCacheTextureSmall));
736    nextLine += mCacheLines.top()->mMaxHeight;
737    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 26, nextLine, 0, mCacheTextureSmall));
738    nextLine += mCacheLines.top()->mMaxHeight;
739    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 34, nextLine, 0, mCacheTextureSmall));
740    nextLine += mCacheLines.top()->mMaxHeight;
741    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 34, nextLine, 0, mCacheTextureSmall));
742    nextLine += mCacheLines.top()->mMaxHeight;
743    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, 42, nextLine, 0, mCacheTextureSmall));
744    nextLine += mCacheLines.top()->mMaxHeight;
745    mCacheLines.push(new CacheTextureLine(mSmallCacheWidth, mSmallCacheHeight - nextLine,
746            nextLine, 0, mCacheTextureSmall));
747
748    //  The first cache is split into 2 lines of height 128, the rest have just one cache line.
749    mCacheLines.push(new CacheTextureLine(maxWidth, 128, 0, 0, mCacheTexture128));
750    mCacheLines.push(new CacheTextureLine(maxWidth, 128, 128, 0, mCacheTexture128));
751    mCacheLines.push(new CacheTextureLine(maxWidth, 256, 0, 0, mCacheTexture256));
752    mCacheLines.push(new CacheTextureLine(maxWidth, 512, 0, 0, mCacheTexture512));
753}
754
755// Avoid having to reallocate memory and render quad by quad
756void FontRenderer::initVertexArrayBuffers() {
757    uint32_t numIndices = mMaxNumberOfQuads * 6;
758    uint32_t indexBufferSizeBytes = numIndices * sizeof(uint16_t);
759    uint16_t* indexBufferData = (uint16_t*) malloc(indexBufferSizeBytes);
760
761    // Four verts, two triangles , six indices per quad
762    for (uint32_t i = 0; i < mMaxNumberOfQuads; i++) {
763        int i6 = i * 6;
764        int i4 = i * 4;
765
766        indexBufferData[i6 + 0] = i4 + 0;
767        indexBufferData[i6 + 1] = i4 + 1;
768        indexBufferData[i6 + 2] = i4 + 2;
769
770        indexBufferData[i6 + 3] = i4 + 0;
771        indexBufferData[i6 + 4] = i4 + 2;
772        indexBufferData[i6 + 5] = i4 + 3;
773    }
774
775    glGenBuffers(1, &mIndexBufferID);
776    Caches::getInstance().bindIndicesBuffer(mIndexBufferID);
777    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexBufferSizeBytes, indexBufferData, GL_STATIC_DRAW);
778
779    free(indexBufferData);
780
781    uint32_t coordSize = 2;
782    uint32_t uvSize = 2;
783    uint32_t vertsPerQuad = 4;
784    uint32_t vertexBufferSize = mMaxNumberOfQuads * vertsPerQuad * coordSize * uvSize;
785    mTextMeshPtr = new float[vertexBufferSize];
786}
787
788// We don't want to allocate anything unless we actually draw text
789void FontRenderer::checkInit() {
790    if (mInitialized) {
791        return;
792    }
793
794    initTextTexture();
795    initVertexArrayBuffers();
796
797    mInitialized = true;
798}
799
800void FontRenderer::checkTextureUpdate() {
801    if (!mUploadTexture && mLastCacheTexture == mCurrentCacheTexture) {
802        return;
803    }
804
805    Caches& caches = Caches::getInstance();
806    GLuint lastTextureId = 0;
807    // Iterate over all the cache lines and see which ones need to be updated
808    for (uint32_t i = 0; i < mCacheLines.size(); i++) {
809        CacheTextureLine* cl = mCacheLines[i];
810        if (cl->mDirty && cl->mCacheTexture->mTexture != NULL) {
811            CacheTexture* cacheTexture = cl->mCacheTexture;
812            uint32_t xOffset = 0;
813            uint32_t yOffset = cl->mCurrentRow;
814            uint32_t width   = cl->mMaxWidth;
815            uint32_t height  = cl->mMaxHeight;
816            void* textureData = cacheTexture->mTexture + (yOffset * width);
817
818            if (cacheTexture->mTextureId != lastTextureId) {
819                caches.activeTexture(0);
820                glBindTexture(GL_TEXTURE_2D, cacheTexture->mTextureId);
821                lastTextureId = cacheTexture->mTextureId;
822            }
823            glTexSubImage2D(GL_TEXTURE_2D, 0, xOffset, yOffset, width, height,
824                    GL_ALPHA, GL_UNSIGNED_BYTE, textureData);
825
826            cl->mDirty = false;
827        }
828    }
829
830    caches.activeTexture(0);
831    glBindTexture(GL_TEXTURE_2D, mCurrentCacheTexture->mTextureId);
832    if (mLinearFiltering != mCurrentCacheTexture->mLinearFiltering) {
833        const GLenum filtering = mLinearFiltering ? GL_LINEAR : GL_NEAREST;
834        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filtering);
835        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filtering);
836        mCurrentCacheTexture->mLinearFiltering = mLinearFiltering;
837    }
838    mLastCacheTexture = mCurrentCacheTexture;
839
840    mUploadTexture = false;
841}
842
843void FontRenderer::issueDrawCommand() {
844    checkTextureUpdate();
845
846    Caches& caches = Caches::getInstance();
847    caches.bindIndicesBuffer(mIndexBufferID);
848    if (!mDrawn) {
849        float* buffer = mTextMeshPtr;
850        int offset = 2;
851
852        bool force = caches.unbindMeshBuffer();
853        caches.bindPositionVertexPointer(force, caches.currentProgram->position, buffer);
854        caches.bindTexCoordsVertexPointer(force, caches.currentProgram->texCoords,
855                buffer + offset);
856    }
857
858    glDrawElements(GL_TRIANGLES, mCurrentQuadIndex * 6, GL_UNSIGNED_SHORT, NULL);
859
860    mDrawn = true;
861}
862
863void FontRenderer::appendMeshQuadNoClip(float x1, float y1, float u1, float v1,
864        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
865        float x4, float y4, float u4, float v4, CacheTexture* texture) {
866    if (texture != mCurrentCacheTexture) {
867        if (mCurrentQuadIndex != 0) {
868            // First, draw everything stored already which uses the previous texture
869            issueDrawCommand();
870            mCurrentQuadIndex = 0;
871        }
872        // Now use the new texture id
873        mCurrentCacheTexture = texture;
874    }
875
876    const uint32_t vertsPerQuad = 4;
877    const uint32_t floatsPerVert = 4;
878    float* currentPos = mTextMeshPtr + mCurrentQuadIndex * vertsPerQuad * floatsPerVert;
879
880    (*currentPos++) = x1;
881    (*currentPos++) = y1;
882    (*currentPos++) = u1;
883    (*currentPos++) = v1;
884
885    (*currentPos++) = x2;
886    (*currentPos++) = y2;
887    (*currentPos++) = u2;
888    (*currentPos++) = v2;
889
890    (*currentPos++) = x3;
891    (*currentPos++) = y3;
892    (*currentPos++) = u3;
893    (*currentPos++) = v3;
894
895    (*currentPos++) = x4;
896    (*currentPos++) = y4;
897    (*currentPos++) = u4;
898    (*currentPos++) = v4;
899
900    mCurrentQuadIndex++;
901}
902
903void FontRenderer::appendMeshQuad(float x1, float y1, float u1, float v1,
904        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
905        float x4, float y4, float u4, float v4, CacheTexture* texture) {
906
907    if (mClip &&
908            (x1 > mClip->right || y1 < mClip->top || x2 < mClip->left || y4 > mClip->bottom)) {
909        return;
910    }
911
912    appendMeshQuadNoClip(x1, y1, u1, v1, x2, y2, u2, v2, x3, y3, u3, v3, x4, y4, u4, v4, texture);
913
914    if (mBounds) {
915        mBounds->left = fmin(mBounds->left, x1);
916        mBounds->top = fmin(mBounds->top, y3);
917        mBounds->right = fmax(mBounds->right, x3);
918        mBounds->bottom = fmax(mBounds->bottom, y1);
919    }
920
921    if (mCurrentQuadIndex == mMaxNumberOfQuads) {
922        issueDrawCommand();
923        mCurrentQuadIndex = 0;
924    }
925}
926
927void FontRenderer::appendRotatedMeshQuad(float x1, float y1, float u1, float v1,
928        float x2, float y2, float u2, float v2, float x3, float y3, float u3, float v3,
929        float x4, float y4, float u4, float v4, CacheTexture* texture) {
930
931    appendMeshQuadNoClip(x1, y1, u1, v1, x2, y2, u2, v2, x3, y3, u3, v3, x4, y4, u4, v4, texture);
932
933    if (mBounds) {
934        mBounds->left = fmin(mBounds->left, fmin(x1, fmin(x2, fmin(x3, x4))));
935        mBounds->top = fmin(mBounds->top, fmin(y1, fmin(y2, fmin(y3, y4))));
936        mBounds->right = fmax(mBounds->right, fmax(x1, fmax(x2, fmax(x3, x4))));
937        mBounds->bottom = fmax(mBounds->bottom, fmax(y1, fmax(y2, fmax(y3, y4))));
938    }
939
940    if (mCurrentQuadIndex == mMaxNumberOfQuads) {
941        issueDrawCommand();
942        mCurrentQuadIndex = 0;
943    }
944}
945
946uint32_t FontRenderer::getRemainingCacheCapacity() {
947    uint32_t remainingCapacity = 0;
948    float totalPixels = 0;
949
950    //avoid divide by zero if the size is 0
951    if (mCacheLines.size() == 0) {
952        return 0;
953    }
954    for(uint32_t i = 0; i < mCacheLines.size(); i ++) {
955         remainingCapacity += (mCacheLines[i]->mMaxWidth - mCacheLines[i]->mCurrentCol);
956         totalPixels += mCacheLines[i]->mMaxWidth;
957    }
958    remainingCapacity = (remainingCapacity * 100) / totalPixels;
959    return remainingCapacity;
960}
961
962void FontRenderer::precacheLatin(SkPaint* paint) {
963    // Remaining capacity is measured in %
964    uint32_t remainingCapacity = getRemainingCacheCapacity();
965    uint32_t precacheIndex = 0;
966
967    // We store a string with letters in a rough frequency of occurrence
968    String16 l("eisarntolcdugpmhbyfvkwzxjq EISARNTOLCDUGPMHBYFVKWZXJQ,.?!()-+@;:'0123456789");
969
970    size_t size = l.size();
971    uint16_t latin[size];
972    paint->utfToGlyphs(l.string(), SkPaint::kUTF16_TextEncoding, size * sizeof(char16_t), latin);
973
974    while (remainingCapacity > 25 && precacheIndex < size) {
975        mCurrentFont->getCachedGlyph(paint, TO_GLYPH(latin[precacheIndex]));
976        remainingCapacity = getRemainingCacheCapacity();
977        precacheIndex++;
978    }
979}
980
981void FontRenderer::setFont(SkPaint* paint, uint32_t fontId, float fontSize) {
982    uint32_t currentNumFonts = mActiveFonts.size();
983    int flags = 0;
984    if (paint->isFakeBoldText()) {
985        flags |= Font::kFakeBold;
986    }
987
988    const float skewX = paint->getTextSkewX();
989    uint32_t italicStyle = *(uint32_t*) &skewX;
990    const float scaleXFloat = paint->getTextScaleX();
991    uint32_t scaleX = *(uint32_t*) &scaleXFloat;
992    SkPaint::Style style = paint->getStyle();
993    const float strokeWidthFloat = paint->getStrokeWidth();
994    uint32_t strokeWidth = *(uint32_t*) &strokeWidthFloat;
995    mCurrentFont = Font::create(this, fontId, fontSize, flags, italicStyle,
996            scaleX, style, strokeWidth);
997
998    const float maxPrecacheFontSize = 40.0f;
999    bool isNewFont = currentNumFonts != mActiveFonts.size();
1000
1001    if (isNewFont && fontSize <= maxPrecacheFontSize) {
1002        precacheLatin(paint);
1003    }
1004}
1005
1006FontRenderer::DropShadow FontRenderer::renderDropShadow(SkPaint* paint, const char *text,
1007        uint32_t startIndex, uint32_t len, int numGlyphs, uint32_t radius) {
1008    checkInit();
1009
1010    if (!mCurrentFont) {
1011        DropShadow image;
1012        image.width = 0;
1013        image.height = 0;
1014        image.image = NULL;
1015        image.penX = 0;
1016        image.penY = 0;
1017        return image;
1018    }
1019
1020    mDrawn = false;
1021    mClip = NULL;
1022    mBounds = NULL;
1023
1024    Rect bounds;
1025    mCurrentFont->measure(paint, text, startIndex, len, numGlyphs, &bounds);
1026
1027    uint32_t paddedWidth = (uint32_t) (bounds.right - bounds.left) + 2 * radius;
1028    uint32_t paddedHeight = (uint32_t) (bounds.top - bounds.bottom) + 2 * radius;
1029    uint8_t* dataBuffer = new uint8_t[paddedWidth * paddedHeight];
1030
1031    for (uint32_t i = 0; i < paddedWidth * paddedHeight; i++) {
1032        dataBuffer[i] = 0;
1033    }
1034
1035    int penX = radius - bounds.left;
1036    int penY = radius - bounds.bottom;
1037
1038    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, penX, penY,
1039            dataBuffer, paddedWidth, paddedHeight);
1040    blurImage(dataBuffer, paddedWidth, paddedHeight, radius);
1041
1042    DropShadow image;
1043    image.width = paddedWidth;
1044    image.height = paddedHeight;
1045    image.image = dataBuffer;
1046    image.penX = penX;
1047    image.penY = penY;
1048
1049    return image;
1050}
1051
1052void FontRenderer::initRender(const Rect* clip, Rect* bounds) {
1053    checkInit();
1054
1055    mDrawn = false;
1056    mBounds = bounds;
1057    mClip = clip;
1058}
1059
1060void FontRenderer::finishRender() {
1061    mBounds = NULL;
1062    mClip = NULL;
1063
1064    if (mCurrentQuadIndex != 0) {
1065        issueDrawCommand();
1066        mCurrentQuadIndex = 0;
1067    }
1068}
1069
1070bool FontRenderer::renderText(SkPaint* paint, const Rect* clip, const char *text,
1071        uint32_t startIndex, uint32_t len, int numGlyphs, int x, int y, Rect* bounds) {
1072    if (!mCurrentFont) {
1073        ALOGE("No font set");
1074        return false;
1075    }
1076
1077    initRender(clip, bounds);
1078    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, x, y);
1079    finishRender();
1080
1081    return mDrawn;
1082}
1083
1084bool FontRenderer::renderPosText(SkPaint* paint, const Rect* clip, const char *text,
1085        uint32_t startIndex, uint32_t len, int numGlyphs, int x, int y,
1086        const float* positions, Rect* bounds) {
1087    if (!mCurrentFont) {
1088        ALOGE("No font set");
1089        return false;
1090    }
1091
1092    initRender(clip, bounds);
1093    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, x, y, positions);
1094    finishRender();
1095
1096    return mDrawn;
1097}
1098
1099bool FontRenderer::renderTextOnPath(SkPaint* paint, const Rect* clip, const char *text,
1100        uint32_t startIndex, uint32_t len, int numGlyphs, SkPath* path,
1101        float hOffset, float vOffset, Rect* bounds) {
1102    if (!mCurrentFont) {
1103        ALOGE("No font set");
1104        return false;
1105    }
1106
1107    initRender(clip, bounds);
1108    mCurrentFont->render(paint, text, startIndex, len, numGlyphs, path, hOffset, vOffset);
1109    finishRender();
1110
1111    return mDrawn;
1112}
1113
1114void FontRenderer::computeGaussianWeights(float* weights, int32_t radius) {
1115    // Compute gaussian weights for the blur
1116    // e is the euler's number
1117    float e = 2.718281828459045f;
1118    float pi = 3.1415926535897932f;
1119    // g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 )
1120    // x is of the form [-radius .. 0 .. radius]
1121    // and sigma varies with radius.
1122    // Based on some experimental radius values and sigma's
1123    // we approximately fit sigma = f(radius) as
1124    // sigma = radius * 0.3  + 0.6
1125    // The larger the radius gets, the more our gaussian blur
1126    // will resemble a box blur since with large sigma
1127    // the gaussian curve begins to lose its shape
1128    float sigma = 0.3f * (float) radius + 0.6f;
1129
1130    // Now compute the coefficints
1131    // We will store some redundant values to save some math during
1132    // the blur calculations
1133    // precompute some values
1134    float coeff1 = 1.0f / (sqrt( 2.0f * pi ) * sigma);
1135    float coeff2 = - 1.0f / (2.0f * sigma * sigma);
1136
1137    float normalizeFactor = 0.0f;
1138    for (int32_t r = -radius; r <= radius; r ++) {
1139        float floatR = (float) r;
1140        weights[r + radius] = coeff1 * pow(e, floatR * floatR * coeff2);
1141        normalizeFactor += weights[r + radius];
1142    }
1143
1144    //Now we need to normalize the weights because all our coefficients need to add up to one
1145    normalizeFactor = 1.0f / normalizeFactor;
1146    for (int32_t r = -radius; r <= radius; r ++) {
1147        weights[r + radius] *= normalizeFactor;
1148    }
1149}
1150
1151void FontRenderer::horizontalBlur(float* weights, int32_t radius,
1152        const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
1153    float blurredPixel = 0.0f;
1154    float currentPixel = 0.0f;
1155
1156    for (int32_t y = 0; y < height; y ++) {
1157
1158        const uint8_t* input = source + y * width;
1159        uint8_t* output = dest + y * width;
1160
1161        for (int32_t x = 0; x < width; x ++) {
1162            blurredPixel = 0.0f;
1163            const float* gPtr = weights;
1164            // Optimization for non-border pixels
1165            if (x > radius && x < (width - radius)) {
1166                const uint8_t *i = input + (x - radius);
1167                for (int r = -radius; r <= radius; r ++) {
1168                    currentPixel = (float) (*i);
1169                    blurredPixel += currentPixel * gPtr[0];
1170                    gPtr++;
1171                    i++;
1172                }
1173            } else {
1174                for (int32_t r = -radius; r <= radius; r ++) {
1175                    // Stepping left and right away from the pixel
1176                    int validW = x + r;
1177                    if (validW < 0) {
1178                        validW = 0;
1179                    }
1180                    if (validW > width - 1) {
1181                        validW = width - 1;
1182                    }
1183
1184                    currentPixel = (float) input[validW];
1185                    blurredPixel += currentPixel * gPtr[0];
1186                    gPtr++;
1187                }
1188            }
1189            *output = (uint8_t)blurredPixel;
1190            output ++;
1191        }
1192    }
1193}
1194
1195void FontRenderer::verticalBlur(float* weights, int32_t radius,
1196        const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) {
1197    float blurredPixel = 0.0f;
1198    float currentPixel = 0.0f;
1199
1200    for (int32_t y = 0; y < height; y ++) {
1201
1202        uint8_t* output = dest + y * width;
1203
1204        for (int32_t x = 0; x < width; x ++) {
1205            blurredPixel = 0.0f;
1206            const float* gPtr = weights;
1207            const uint8_t* input = source + x;
1208            // Optimization for non-border pixels
1209            if (y > radius && y < (height - radius)) {
1210                const uint8_t *i = input + ((y - radius) * width);
1211                for (int32_t r = -radius; r <= radius; r ++) {
1212                    currentPixel = (float)(*i);
1213                    blurredPixel += currentPixel * gPtr[0];
1214                    gPtr++;
1215                    i += width;
1216                }
1217            } else {
1218                for (int32_t r = -radius; r <= radius; r ++) {
1219                    int validH = y + r;
1220                    // Clamp to zero and width
1221                    if (validH < 0) {
1222                        validH = 0;
1223                    }
1224                    if (validH > height - 1) {
1225                        validH = height - 1;
1226                    }
1227
1228                    const uint8_t *i = input + validH * width;
1229                    currentPixel = (float) (*i);
1230                    blurredPixel += currentPixel * gPtr[0];
1231                    gPtr++;
1232                }
1233            }
1234            *output = (uint8_t) blurredPixel;
1235            output ++;
1236        }
1237    }
1238}
1239
1240
1241void FontRenderer::blurImage(uint8_t *image, int32_t width, int32_t height, int32_t radius) {
1242    float *gaussian = new float[2 * radius + 1];
1243    computeGaussianWeights(gaussian, radius);
1244
1245    uint8_t* scratch = new uint8_t[width * height];
1246
1247    horizontalBlur(gaussian, radius, image, scratch, width, height);
1248    verticalBlur(gaussian, radius, scratch, image, width, height);
1249
1250    delete[] gaussian;
1251    delete[] scratch;
1252}
1253
1254}; // namespace uirenderer
1255}; // namespace android
1256