Font.cpp revision 3ed192760314dc976cd02f62ac49798daa89b4b1 
1/*
2 * Copyright (C) 2012 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#define ATRACE_TAG ATRACE_TAG_VIEW
19
20#include <cutils/compiler.h>
21
22#include <utils/JenkinsHash.h>
23#include <utils/Trace.h>
24
25#include <SkGlyph.h>
26#include <SkUtils.h>
27
28#include "FontUtil.h"
29#include "Font.h"
30#include "../Debug.h"
31#include "../FontRenderer.h"
32#include "../PixelBuffer.h"
33#include "../Properties.h"
34
35namespace android {
36namespace uirenderer {
37
38///////////////////////////////////////////////////////////////////////////////
39// Font
40///////////////////////////////////////////////////////////////////////////////
41
42Font::Font(FontRenderer* state, const Font::FontDescription& desc) :
43        mState(state), mDescription(desc) {
44}
45
46Font::FontDescription::FontDescription(const SkPaint* paint, const mat4& matrix) {
47    mFontId = SkTypeface::UniqueID(paint->getTypeface());
48    mFontSize = paint->getTextSize();
49    mFlags = 0;
50    if (paint->isFakeBoldText()) {
51        mFlags |= Font::kFakeBold;
52    }
53    mItalicStyle = paint->getTextSkewX();
54    mScaleX = paint->getTextScaleX();
55    mStyle = paint->getStyle();
56    mStrokeWidth = paint->getStrokeWidth();
57    mAntiAliasing = paint->isAntiAlias();
58    mHinting = paint->getHinting();
59    mLookupTransform.reset();
60    mLookupTransform[SkMatrix::kMScaleX] = roundf(fmaxf(1.0f, matrix[mat4::kScaleX]));
61    mLookupTransform[SkMatrix::kMScaleY] = roundf(fmaxf(1.0f, matrix[mat4::kScaleY]));
62    if (!mLookupTransform.invert(&mInverseLookupTransform)) {
63        ALOGW("Could not query the inverse lookup transform for this font");
64    }
65}
66
67Font::~Font() {
68    mState->removeFont(this);
69
70    for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) {
71        delete mCachedGlyphs.valueAt(i);
72    }
73}
74
75hash_t Font::FontDescription::hash() const {
76    uint32_t hash = JenkinsHashMix(0, mFontId);
77    hash = JenkinsHashMix(hash, android::hash_type(mFontSize));
78    hash = JenkinsHashMix(hash, android::hash_type(mFlags));
79    hash = JenkinsHashMix(hash, android::hash_type(mItalicStyle));
80    hash = JenkinsHashMix(hash, android::hash_type(mScaleX));
81    hash = JenkinsHashMix(hash, android::hash_type(mStyle));
82    hash = JenkinsHashMix(hash, android::hash_type(mStrokeWidth));
83    hash = JenkinsHashMix(hash, int(mAntiAliasing));
84    hash = JenkinsHashMix(hash, android::hash_type(mHinting));
85    hash = JenkinsHashMix(hash, android::hash_type(mLookupTransform[SkMatrix::kMScaleX]));
86    hash = JenkinsHashMix(hash, android::hash_type(mLookupTransform[SkMatrix::kMScaleY]));
87    return JenkinsHashWhiten(hash);
88}
89
90int Font::FontDescription::compare(const Font::FontDescription& lhs,
91        const Font::FontDescription& rhs) {
92    int deltaInt = int(lhs.mFontId) - int(rhs.mFontId);
93    if (deltaInt != 0) return deltaInt;
94
95    if (lhs.mFontSize < rhs.mFontSize) return -1;
96    if (lhs.mFontSize > rhs.mFontSize) return +1;
97
98    if (lhs.mItalicStyle < rhs.mItalicStyle) return -1;
99    if (lhs.mItalicStyle > rhs.mItalicStyle) return +1;
100
101    deltaInt = int(lhs.mFlags) - int(rhs.mFlags);
102    if (deltaInt != 0) return deltaInt;
103
104    if (lhs.mScaleX < rhs.mScaleX) return -1;
105    if (lhs.mScaleX > rhs.mScaleX) return +1;
106
107    deltaInt = int(lhs.mStyle) - int(rhs.mStyle);
108    if (deltaInt != 0) return deltaInt;
109
110    if (lhs.mStrokeWidth < rhs.mStrokeWidth) return -1;
111    if (lhs.mStrokeWidth > rhs.mStrokeWidth) return +1;
112
113    deltaInt = int(lhs.mAntiAliasing) - int(rhs.mAntiAliasing);
114    if (deltaInt != 0) return deltaInt;
115
116    deltaInt = int(lhs.mHinting) - int(rhs.mHinting);
117    if (deltaInt != 0) return deltaInt;
118
119    if (lhs.mLookupTransform[SkMatrix::kMScaleX] <
120            rhs.mLookupTransform[SkMatrix::kMScaleX]) return -1;
121    if (lhs.mLookupTransform[SkMatrix::kMScaleX] >
122            rhs.mLookupTransform[SkMatrix::kMScaleX]) return +1;
123
124    if (lhs.mLookupTransform[SkMatrix::kMScaleY] <
125            rhs.mLookupTransform[SkMatrix::kMScaleY]) return -1;
126    if (lhs.mLookupTransform[SkMatrix::kMScaleY] >
127            rhs.mLookupTransform[SkMatrix::kMScaleY]) return +1;
128
129    return 0;
130}
131
132void Font::invalidateTextureCache(CacheTexture* cacheTexture) {
133    for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) {
134        CachedGlyphInfo* cachedGlyph = mCachedGlyphs.valueAt(i);
135        if (!cacheTexture || cachedGlyph->mCacheTexture == cacheTexture) {
136            cachedGlyph->mIsValid = false;
137        }
138    }
139}
140
141void Font::measureCachedGlyph(CachedGlyphInfo *glyph, int x, int y,
142        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
143    int nPenX = x + glyph->mBitmapLeft;
144    int nPenY = y + glyph->mBitmapTop;
145
146    int width = (int) glyph->mBitmapWidth;
147    int height = (int) glyph->mBitmapHeight;
148
149    if (bounds->bottom > nPenY) {
150        bounds->bottom = nPenY;
151    }
152    if (bounds->left > nPenX) {
153        bounds->left = nPenX;
154    }
155    if (bounds->right < nPenX + width) {
156        bounds->right = nPenX + width;
157    }
158    if (bounds->top < nPenY + height) {
159        bounds->top = nPenY + height;
160    }
161}
162
163void Font::drawCachedGlyph(CachedGlyphInfo* glyph, int x, int y,
164        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
165    float nPenX = x + glyph->mBitmapLeft;
166    float nPenY = y + glyph->mBitmapTop + glyph->mBitmapHeight;
167
168    float width = (float) glyph->mBitmapWidth;
169    float height = (float) glyph->mBitmapHeight;
170
171    float u1 = glyph->mBitmapMinU;
172    float u2 = glyph->mBitmapMaxU;
173    float v1 = glyph->mBitmapMinV;
174    float v2 = glyph->mBitmapMaxV;
175
176    mState->appendMeshQuad(nPenX, nPenY, u1, v2,
177            nPenX + width, nPenY, u2, v2,
178            nPenX + width, nPenY - height, u2, v1,
179            nPenX, nPenY - height, u1, v1, glyph->mCacheTexture);
180}
181
182void Font::drawCachedGlyphTransformed(CachedGlyphInfo* glyph, int x, int y,
183        uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* pos) {
184    SkPoint p[4];
185    p[0].iset(glyph->mBitmapLeft, glyph->mBitmapTop + glyph->mBitmapHeight);
186    p[1].iset(glyph->mBitmapLeft + glyph->mBitmapWidth, glyph->mBitmapTop + glyph->mBitmapHeight);
187    p[2].iset(glyph->mBitmapLeft + glyph->mBitmapWidth, glyph->mBitmapTop);
188    p[3].iset(glyph->mBitmapLeft, glyph->mBitmapTop);
189
190    mDescription.mInverseLookupTransform.mapPoints(p, 4);
191
192    p[0].offset(x, y);
193    p[1].offset(x, y);
194    p[2].offset(x, y);
195    p[3].offset(x, y);
196
197    float u1 = glyph->mBitmapMinU;
198    float u2 = glyph->mBitmapMaxU;
199    float v1 = glyph->mBitmapMinV;
200    float v2 = glyph->mBitmapMaxV;
201
202    mState->appendRotatedMeshQuad(
203            p[0].x(), p[0].y(), u1, v2,
204            p[1].x(), p[1].y(), u2, v2,
205            p[2].x(), p[2].y(), u2, v1,
206            p[3].x(), p[3].y(), u1, v1, glyph->mCacheTexture);
207}
208
209void Font::drawCachedGlyphBitmap(CachedGlyphInfo* glyph, int x, int y, uint8_t* bitmap,
210        uint32_t bitmapWidth, uint32_t bitmapHeight, Rect* bounds, const float* pos) {
211    int dstX = x + glyph->mBitmapLeft;
212    int dstY = y + glyph->mBitmapTop;
213
214    CacheTexture* cacheTexture = glyph->mCacheTexture;
215
216    uint32_t cacheWidth = cacheTexture->getWidth();
217    uint32_t startY = glyph->mStartY * cacheWidth;
218    uint32_t endY = startY + (glyph->mBitmapHeight * cacheWidth);
219
220    PixelBuffer* pixelBuffer = cacheTexture->getPixelBuffer();
221    const uint8_t* cacheBuffer = pixelBuffer->map();
222
223    for (uint32_t cacheY = startY, bitmapY = dstY * bitmapWidth; cacheY < endY;
224            cacheY += cacheWidth, bitmapY += bitmapWidth) {
225        memcpy(&bitmap[bitmapY + dstX], &cacheBuffer[cacheY + glyph->mStartX], glyph->mBitmapWidth);
226    }
227}
228
229void Font::drawCachedGlyph(CachedGlyphInfo* glyph, float x, float hOffset, float vOffset,
230        SkPathMeasure& measure, SkPoint* position, SkVector* tangent) {
231    const float halfWidth = glyph->mBitmapWidth * 0.5f;
232    const float height = glyph->mBitmapHeight;
233
234    vOffset += glyph->mBitmapTop + height;
235
236    SkPoint destination[4];
237    bool ok = measure.getPosTan(x + hOffset + glyph->mBitmapLeft + halfWidth, position, tangent);
238    if (!ok) {
239        ALOGW("The path for drawTextOnPath is empty or null");
240    }
241
242    // Move along the tangent and offset by the normal
243    destination[0].set(-tangent->fX * halfWidth - tangent->fY * vOffset,
244            -tangent->fY * halfWidth + tangent->fX * vOffset);
245    destination[1].set(tangent->fX * halfWidth - tangent->fY * vOffset,
246            tangent->fY * halfWidth + tangent->fX * vOffset);
247    destination[2].set(destination[1].fX + tangent->fY * height,
248            destination[1].fY - tangent->fX * height);
249    destination[3].set(destination[0].fX + tangent->fY * height,
250            destination[0].fY - tangent->fX * height);
251
252    const float u1 = glyph->mBitmapMinU;
253    const float u2 = glyph->mBitmapMaxU;
254    const float v1 = glyph->mBitmapMinV;
255    const float v2 = glyph->mBitmapMaxV;
256
257    mState->appendRotatedMeshQuad(
258            position->x() + destination[0].x(),
259            position->y() + destination[0].y(), u1, v2,
260            position->x() + destination[1].x(),
261            position->y() + destination[1].y(), u2, v2,
262            position->x() + destination[2].x(),
263            position->y() + destination[2].y(), u2, v1,
264            position->x() + destination[3].x(),
265            position->y() + destination[3].y(), u1, v1,
266            glyph->mCacheTexture);
267}
268
269CachedGlyphInfo* Font::getCachedGlyph(SkPaint* paint, glyph_t textUnit, bool precaching) {
270    CachedGlyphInfo* cachedGlyph = mCachedGlyphs.valueFor(textUnit);
271    if (cachedGlyph) {
272        // Is the glyph still in texture cache?
273        if (!cachedGlyph->mIsValid) {
274            const SkGlyph& skiaGlyph = GET_METRICS(paint, textUnit,
275                    &mDescription.mLookupTransform);
276            updateGlyphCache(paint, skiaGlyph, cachedGlyph, precaching);
277        }
278    } else {
279        cachedGlyph = cacheGlyph(paint, textUnit, precaching);
280    }
281
282    return cachedGlyph;
283}
284
285void Font::render(SkPaint* paint, const char *text, uint32_t start, uint32_t len,
286            int numGlyphs, int x, int y, const float* positions) {
287    render(paint, text, start, len, numGlyphs, x, y, FRAMEBUFFER, NULL,
288            0, 0, NULL, positions);
289}
290
291void Font::render(SkPaint* paint, const char *text, uint32_t start, uint32_t len,
292        int numGlyphs, SkPath* path, float hOffset, float vOffset) {
293    if (numGlyphs == 0 || text == NULL || len == 0) {
294        return;
295    }
296
297    text += start;
298
299    int glyphsCount = 0;
300    SkFixed prevRsbDelta = 0;
301
302    float penX = 0.0f;
303
304    SkPoint position;
305    SkVector tangent;
306
307    SkPathMeasure measure(*path, false);
308    float pathLength = SkScalarToFloat(measure.getLength());
309
310    if (paint->getTextAlign() != SkPaint::kLeft_Align) {
311        float textWidth = SkScalarToFloat(paint->measureText(text, len));
312        float pathOffset = pathLength;
313        if (paint->getTextAlign() == SkPaint::kCenter_Align) {
314            textWidth *= 0.5f;
315            pathOffset *= 0.5f;
316        }
317        penX += pathOffset - textWidth;
318    }
319
320    while (glyphsCount < numGlyphs && penX < pathLength) {
321        glyph_t glyph = GET_GLYPH(text);
322
323        if (IS_END_OF_STRING(glyph)) {
324            break;
325        }
326
327        CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph);
328        penX += SkFixedToFloat(AUTO_KERN(prevRsbDelta, cachedGlyph->mLsbDelta));
329        prevRsbDelta = cachedGlyph->mRsbDelta;
330
331        if (cachedGlyph->mIsValid && cachedGlyph->mCacheTexture) {
332            drawCachedGlyph(cachedGlyph, penX, hOffset, vOffset, measure, &position, &tangent);
333        }
334
335        penX += SkFixedToFloat(cachedGlyph->mAdvanceX);
336
337        glyphsCount++;
338    }
339}
340
341void Font::measure(SkPaint* paint, const char* text, uint32_t start, uint32_t len,
342        int numGlyphs, Rect *bounds, const float* positions) {
343    if (bounds == NULL) {
344        ALOGE("No return rectangle provided to measure text");
345        return;
346    }
347    bounds->set(1e6, -1e6, -1e6, 1e6);
348    render(paint, text, start, len, numGlyphs, 0, 0, MEASURE, NULL, 0, 0, bounds, positions);
349}
350
351void Font::precache(SkPaint* paint, const char* text, int numGlyphs) {
352    ATRACE_NAME("precacheText");
353
354    if (numGlyphs == 0 || text == NULL) {
355        return;
356    }
357
358    int glyphsCount = 0;
359    while (glyphsCount < numGlyphs) {
360        glyph_t glyph = GET_GLYPH(text);
361
362        // Reached the end of the string
363        if (IS_END_OF_STRING(glyph)) {
364            break;
365        }
366
367        CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph, true);
368        glyphsCount++;
369    }
370}
371
372void Font::render(SkPaint* paint, const char* text, uint32_t start, uint32_t len,
373        int numGlyphs, int x, int y, RenderMode mode, uint8_t *bitmap,
374        uint32_t bitmapW, uint32_t bitmapH, Rect* bounds, const float* positions) {
375    if (numGlyphs == 0 || text == NULL || len == 0) {
376        return;
377    }
378
379    static RenderGlyph gRenderGlyph[] = {
380            &android::uirenderer::Font::drawCachedGlyph,
381            &android::uirenderer::Font::drawCachedGlyphTransformed,
382            &android::uirenderer::Font::drawCachedGlyphBitmap,
383            &android::uirenderer::Font::drawCachedGlyphBitmap,
384            &android::uirenderer::Font::measureCachedGlyph,
385            &android::uirenderer::Font::measureCachedGlyph
386    };
387    RenderGlyph render = gRenderGlyph[(mode << 1) + !mIdentityTransform];
388
389    text += start;
390    int glyphsCount = 0;
391
392    const SkPaint::Align align = paint->getTextAlign();
393
394    while (glyphsCount < numGlyphs) {
395        glyph_t glyph = GET_GLYPH(text);
396
397        // Reached the end of the string
398        if (IS_END_OF_STRING(glyph)) {
399            break;
400        }
401
402        CachedGlyphInfo* cachedGlyph = getCachedGlyph(paint, glyph);
403
404        // If it's still not valid, we couldn't cache it, so we shouldn't
405        // draw garbage; also skip empty glyphs (spaces)
406        if (cachedGlyph->mIsValid && cachedGlyph->mCacheTexture) {
407            int penX = x + (int) roundf(positions[(glyphsCount << 1)]);
408            int penY = y + (int) roundf(positions[(glyphsCount << 1) + 1]);
409
410            (*this.*render)(cachedGlyph, penX, penY,
411                    bitmap, bitmapW, bitmapH, bounds, positions);
412        }
413
414        glyphsCount++;
415    }
416}
417
418void Font::updateGlyphCache(SkPaint* paint, const SkGlyph& skiaGlyph, CachedGlyphInfo* glyph,
419        bool precaching) {
420    glyph->mAdvanceX = skiaGlyph.fAdvanceX;
421    glyph->mAdvanceY = skiaGlyph.fAdvanceY;
422    glyph->mBitmapLeft = skiaGlyph.fLeft;
423    glyph->mBitmapTop = skiaGlyph.fTop;
424    glyph->mLsbDelta = skiaGlyph.fLsbDelta;
425    glyph->mRsbDelta = skiaGlyph.fRsbDelta;
426
427    uint32_t startX = 0;
428    uint32_t startY = 0;
429
430    // Get the bitmap for the glyph
431    if (!skiaGlyph.fImage) {
432        paint->findImage(skiaGlyph, &mDescription.mLookupTransform);
433    }
434    mState->cacheBitmap(skiaGlyph, glyph, &startX, &startY, precaching);
435
436    if (!glyph->mIsValid) {
437        return;
438    }
439
440    uint32_t endX = startX + skiaGlyph.fWidth;
441    uint32_t endY = startY + skiaGlyph.fHeight;
442
443    glyph->mStartX = startX;
444    glyph->mStartY = startY;
445    glyph->mBitmapWidth = skiaGlyph.fWidth;
446    glyph->mBitmapHeight = skiaGlyph.fHeight;
447
448    bool empty = skiaGlyph.fWidth == 0 || skiaGlyph.fHeight == 0;
449    if (!empty) {
450        uint32_t cacheWidth = glyph->mCacheTexture->getWidth();
451        uint32_t cacheHeight = glyph->mCacheTexture->getHeight();
452
453        glyph->mBitmapMinU = startX / (float) cacheWidth;
454        glyph->mBitmapMinV = startY / (float) cacheHeight;
455        glyph->mBitmapMaxU = endX / (float) cacheWidth;
456        glyph->mBitmapMaxV = endY / (float) cacheHeight;
457
458        mState->setTextureDirty();
459    }
460}
461
462CachedGlyphInfo* Font::cacheGlyph(SkPaint* paint, glyph_t glyph, bool precaching) {
463    CachedGlyphInfo* newGlyph = new CachedGlyphInfo();
464    mCachedGlyphs.add(glyph, newGlyph);
465
466    const SkGlyph& skiaGlyph = GET_METRICS(paint, glyph, &mDescription.mLookupTransform);
467    newGlyph->mIsValid = false;
468    newGlyph->mGlyphIndex = skiaGlyph.fID;
469
470    updateGlyphCache(paint, skiaGlyph, newGlyph, precaching);
471
472    return newGlyph;
473}
474
475Font* Font::create(FontRenderer* state, const SkPaint* paint, const mat4& matrix) {
476    FontDescription description(paint, matrix);
477    Font* font = state->mActiveFonts.get(description);
478
479    if (!font) {
480        font = new Font(state, description);
481        state->mActiveFonts.put(description, font);
482    }
483    font->mIdentityTransform = matrix.isIdentity();
484
485    return font;
486}
487
488}; // namespace uirenderer
489}; // namespace android
490