FontRenderer.cpp revision e2d345ea67e2960b37bfdc0fc8626d1bfa747404
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 "FontRenderer.h" 26 27namespace android { 28namespace uirenderer { 29 30/////////////////////////////////////////////////////////////////////////////// 31// Defines 32/////////////////////////////////////////////////////////////////////////////// 33 34#define DEFAULT_TEXT_CACHE_WIDTH 1024 35#define DEFAULT_TEXT_CACHE_HEIGHT 256 36 37/////////////////////////////////////////////////////////////////////////////// 38// Font 39/////////////////////////////////////////////////////////////////////////////// 40 41Font::Font(FontRenderer* state, uint32_t fontId, float fontSize) : 42 mState(state), mFontId(fontId), mFontSize(fontSize) { 43} 44 45 46Font::~Font() { 47 for (uint32_t ct = 0; ct < mState->mActiveFonts.size(); ct++) { 48 if (mState->mActiveFonts[ct] == this) { 49 mState->mActiveFonts.removeAt(ct); 50 break; 51 } 52 } 53 54 for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) { 55 CachedGlyphInfo* glyph = mCachedGlyphs.valueAt(i); 56 delete glyph; 57 } 58} 59 60void Font::invalidateTextureCache() { 61 for (uint32_t i = 0; i < mCachedGlyphs.size(); i++) { 62 mCachedGlyphs.valueAt(i)->mIsValid = false; 63 } 64} 65 66void Font::measureCachedGlyph(CachedGlyphInfo *glyph, int x, int y, Rect *bounds) { 67 int nPenX = x + glyph->mBitmapLeft; 68 int nPenY = y + glyph->mBitmapTop; 69 70 int width = (int) glyph->mBitmapWidth; 71 int height = (int) glyph->mBitmapHeight; 72 73 if (bounds->bottom > nPenY) { 74 bounds->bottom = nPenY; 75 } 76 if (bounds->left > nPenX) { 77 bounds->left = nPenX; 78 } 79 if (bounds->right < nPenX + width) { 80 bounds->right = nPenX + width; 81 } 82 if (bounds->top < nPenY + height) { 83 bounds->top = nPenY + height; 84 } 85} 86 87void Font::drawCachedGlyph(CachedGlyphInfo* glyph, int x, int y) { 88 int nPenX = x + glyph->mBitmapLeft; 89 int nPenY = y + glyph->mBitmapTop + glyph->mBitmapHeight; 90 91 float u1 = glyph->mBitmapMinU; 92 float u2 = glyph->mBitmapMaxU; 93 float v1 = glyph->mBitmapMinV; 94 float v2 = glyph->mBitmapMaxV; 95 96 int width = (int) glyph->mBitmapWidth; 97 int height = (int) glyph->mBitmapHeight; 98 99 mState->appendMeshQuad(nPenX, nPenY, 0, u1, v2, 100 nPenX + width, nPenY, 0, u2, v2, 101 nPenX + width, nPenY - height, 0, u2, v1, 102 nPenX, nPenY - height, 0, u1, v1); 103} 104 105void Font::drawCachedGlyph(CachedGlyphInfo* glyph, int x, int y, 106 uint8_t* bitmap, uint32_t bitmapW, uint32_t bitmapH) { 107 int nPenX = x + glyph->mBitmapLeft; 108 int nPenY = y + glyph->mBitmapTop; 109 110 uint32_t endX = glyph->mStartX + glyph->mBitmapWidth; 111 uint32_t endY = glyph->mStartY + glyph->mBitmapHeight; 112 113 uint32_t cacheWidth = mState->getCacheWidth(); 114 const uint8_t* cacheBuffer = mState->getTextTextureData(); 115 116 uint32_t cacheX = 0, cacheY = 0; 117 int32_t bX = 0, bY = 0; 118 for (cacheX = glyph->mStartX, bX = nPenX; cacheX < endX; cacheX++, bX++) { 119 for (cacheY = glyph->mStartY, bY = nPenY; cacheY < endY; cacheY++, bY++) { 120 if (bX < 0 || bY < 0 || bX >= (int32_t) bitmapW || bY >= (int32_t) bitmapH) { 121 LOGE("Skipping invalid index"); 122 continue; 123 } 124 uint8_t tempCol = cacheBuffer[cacheY * cacheWidth + cacheX]; 125 bitmap[bY * bitmapW + bX] = tempCol; 126 } 127 } 128 129} 130 131Font::CachedGlyphInfo* Font::getCachedUTFChar(SkPaint* paint, int32_t utfChar) { 132 CachedGlyphInfo* cachedGlyph = NULL; 133 ssize_t index = mCachedGlyphs.indexOfKey(utfChar); 134 if (index >= 0) { 135 cachedGlyph = mCachedGlyphs.valueAt(index); 136 } else { 137 cachedGlyph = cacheGlyph(paint, utfChar); 138 } 139 140 // Is the glyph still in texture cache? 141 if (!cachedGlyph->mIsValid) { 142 const SkGlyph& skiaGlyph = paint->getUnicharMetrics(utfChar); 143 updateGlyphCache(paint, skiaGlyph, cachedGlyph); 144 } 145 146 return cachedGlyph; 147} 148 149void Font::renderUTF(SkPaint* paint, const char* text, uint32_t start, uint32_t len, 150 int numGlyphs, int x, int y, uint8_t *bitmap, uint32_t bitmapW, uint32_t bitmapH) { 151 if (bitmap != NULL && bitmapW > 0 && bitmapH > 0) { 152 renderUTF(paint, text, start, len, numGlyphs, x, y, BITMAP, bitmap, 153 bitmapW, bitmapH, NULL); 154 } else { 155 renderUTF(paint, text, start, len, numGlyphs, x, y, FRAMEBUFFER, NULL, 0, 0, NULL); 156 } 157 158} 159 160void Font::measureUTF(SkPaint* paint, const char* text, uint32_t start, uint32_t len, 161 int numGlyphs, Rect *bounds) { 162 if (bounds == NULL) { 163 LOGE("No return rectangle provided to measure text"); 164 return; 165 } 166 bounds->set(1e6, -1e6, -1e6, 1e6); 167 renderUTF(paint, text, start, len, numGlyphs, 0, 0, MEASURE, NULL, 0, 0, bounds); 168} 169 170#define SkAutoKern_AdjustF(prev, next) (((next) - (prev) + 32) >> 6 << 16) 171 172void Font::renderUTF(SkPaint* paint, const char* text, uint32_t start, uint32_t len, 173 int numGlyphs, int x, int y, RenderMode mode, uint8_t *bitmap, 174 uint32_t bitmapW, uint32_t bitmapH,Rect *bounds) { 175 if (numGlyphs == 0 || text == NULL || len == 0) { 176 return; 177 } 178 179 SkFixed penX = SkIntToFixed(x); 180 int penY = y; 181 int glyphsLeft = 1; 182 if (numGlyphs > 0) { 183 glyphsLeft = numGlyphs; 184 } 185 186 SkFixed prevRsbDelta = 0; 187 penX += SK_Fixed1 / 2; 188 189 text += start; 190 191 while (glyphsLeft > 0) { 192 int32_t utfChar = SkUTF16_NextUnichar((const uint16_t**) &text); 193 194 // Reached the end of the string 195 if (utfChar < 0) { 196 break; 197 } 198 199 CachedGlyphInfo* cachedGlyph = getCachedUTFChar(paint, utfChar); 200 penX += SkAutoKern_AdjustF(prevRsbDelta, cachedGlyph->mLsbDelta); 201 prevRsbDelta = cachedGlyph->mRsbDelta; 202 203 // If it's still not valid, we couldn't cache it, so we shouldn't draw garbage 204 if (cachedGlyph->mIsValid) { 205 switch(mode) { 206 case FRAMEBUFFER: 207 drawCachedGlyph(cachedGlyph, SkFixedFloor(penX), penY); 208 break; 209 case BITMAP: 210 drawCachedGlyph(cachedGlyph, SkFixedFloor(penX), penY, bitmap, bitmapW, bitmapH); 211 break; 212 case MEASURE: 213 measureCachedGlyph(cachedGlyph, SkFixedFloor(penX), penY, bounds); 214 break; 215 } 216 } 217 218 penX += cachedGlyph->mAdvanceX; 219 220 // If we were given a specific number of glyphs, decrement 221 if (numGlyphs > 0) { 222 glyphsLeft--; 223 } 224 } 225} 226 227void Font::updateGlyphCache(SkPaint* paint, const SkGlyph& skiaGlyph, CachedGlyphInfo* glyph) { 228 glyph->mAdvanceX = skiaGlyph.fAdvanceX; 229 glyph->mAdvanceY = skiaGlyph.fAdvanceY; 230 glyph->mBitmapLeft = skiaGlyph.fLeft; 231 glyph->mBitmapTop = skiaGlyph.fTop; 232 glyph->mLsbDelta = skiaGlyph.fLsbDelta; 233 glyph->mRsbDelta = skiaGlyph.fRsbDelta; 234 235 uint32_t startX = 0; 236 uint32_t startY = 0; 237 238 // Get the bitmap for the glyph 239 paint->findImage(skiaGlyph); 240 glyph->mIsValid = mState->cacheBitmap(skiaGlyph, &startX, &startY); 241 242 if (!glyph->mIsValid) { 243 return; 244 } 245 246 uint32_t endX = startX + skiaGlyph.fWidth; 247 uint32_t endY = startY + skiaGlyph.fHeight; 248 249 glyph->mStartX = startX; 250 glyph->mStartY = startY; 251 glyph->mBitmapWidth = skiaGlyph.fWidth; 252 glyph->mBitmapHeight = skiaGlyph.fHeight; 253 254 uint32_t cacheWidth = mState->getCacheWidth(); 255 uint32_t cacheHeight = mState->getCacheHeight(); 256 257 glyph->mBitmapMinU = (float) startX / (float) cacheWidth; 258 glyph->mBitmapMinV = (float) startY / (float) cacheHeight; 259 glyph->mBitmapMaxU = (float) endX / (float) cacheWidth; 260 glyph->mBitmapMaxV = (float) endY / (float) cacheHeight; 261 262 mState->mUploadTexture = true; 263} 264 265Font::CachedGlyphInfo* Font::cacheGlyph(SkPaint* paint, int32_t glyph) { 266 CachedGlyphInfo* newGlyph = new CachedGlyphInfo(); 267 mCachedGlyphs.add(glyph, newGlyph); 268 269 const SkGlyph& skiaGlyph = paint->getUnicharMetrics(glyph); 270 newGlyph->mGlyphIndex = skiaGlyph.fID; 271 newGlyph->mIsValid = false; 272 273 updateGlyphCache(paint, skiaGlyph, newGlyph); 274 275 return newGlyph; 276} 277 278Font* Font::create(FontRenderer* state, uint32_t fontId, float fontSize) { 279 Vector<Font*> &activeFonts = state->mActiveFonts; 280 281 for (uint32_t i = 0; i < activeFonts.size(); i++) { 282 Font* font = activeFonts[i]; 283 if (font->mFontId == fontId && font->mFontSize == fontSize) { 284 return font; 285 } 286 } 287 288 Font* newFont = new Font(state, fontId, fontSize); 289 activeFonts.push(newFont); 290 return newFont; 291} 292 293/////////////////////////////////////////////////////////////////////////////// 294// FontRenderer 295/////////////////////////////////////////////////////////////////////////////// 296 297FontRenderer::FontRenderer() { 298 LOGD("Creating FontRenderer"); 299 300 mGammaTable = NULL; 301 mInitialized = false; 302 mMaxNumberOfQuads = 1024; 303 mCurrentQuadIndex = 0; 304 mTextureId = 0; 305 306 mTextMeshPtr = NULL; 307 mTextTexture = NULL; 308 309 mIndexBufferID = 0; 310 311 mCacheWidth = DEFAULT_TEXT_CACHE_WIDTH; 312 mCacheHeight = DEFAULT_TEXT_CACHE_HEIGHT; 313 314 char property[PROPERTY_VALUE_MAX]; 315 if (property_get(PROPERTY_TEXT_CACHE_WIDTH, property, NULL) > 0) { 316 LOGD(" Setting text cache width to %s pixels", property); 317 mCacheWidth = atoi(property); 318 } else { 319 LOGD(" Using default text cache width of %i pixels", mCacheWidth); 320 } 321 322 if (property_get(PROPERTY_TEXT_CACHE_HEIGHT, property, NULL) > 0) { 323 LOGD(" Setting text cache width to %s pixels", property); 324 mCacheHeight = atoi(property); 325 } else { 326 LOGD(" Using default text cache height of %i pixels", mCacheHeight); 327 } 328} 329 330FontRenderer::~FontRenderer() { 331 for (uint32_t i = 0; i < mCacheLines.size(); i++) { 332 delete mCacheLines[i]; 333 } 334 mCacheLines.clear(); 335 336 if (mInitialized) { 337 delete[] mTextMeshPtr; 338 delete[] mTextTexture; 339 } 340 341 if (mTextureId) { 342 glDeleteTextures(1, &mTextureId); 343 } 344 345 Vector<Font*> fontsToDereference = mActiveFonts; 346 for (uint32_t i = 0; i < fontsToDereference.size(); i++) { 347 delete fontsToDereference[i]; 348 } 349} 350 351void FontRenderer::flushAllAndInvalidate() { 352 if (mCurrentQuadIndex != 0) { 353 issueDrawCommand(); 354 mCurrentQuadIndex = 0; 355 } 356 for (uint32_t i = 0; i < mActiveFonts.size(); i++) { 357 mActiveFonts[i]->invalidateTextureCache(); 358 } 359 for (uint32_t i = 0; i < mCacheLines.size(); i++) { 360 mCacheLines[i]->mCurrentCol = 0; 361 } 362} 363 364bool FontRenderer::cacheBitmap(const SkGlyph& glyph, uint32_t* retOriginX, uint32_t* retOriginY) { 365 // If the glyph is too tall, don't cache it 366 if (glyph.fHeight > mCacheLines[mCacheLines.size() - 1]->mMaxHeight) { 367 LOGE("Font size to large to fit in cache. width, height = %i, %i", 368 (int) glyph.fWidth, (int) glyph.fHeight); 369 return false; 370 } 371 372 // Now copy the bitmap into the cache texture 373 uint32_t startX = 0; 374 uint32_t startY = 0; 375 376 bool bitmapFit = false; 377 for (uint32_t i = 0; i < mCacheLines.size(); i++) { 378 bitmapFit = mCacheLines[i]->fitBitmap(glyph, &startX, &startY); 379 if (bitmapFit) { 380 break; 381 } 382 } 383 384 // If the new glyph didn't fit, flush the state so far and invalidate everything 385 if (!bitmapFit) { 386 flushAllAndInvalidate(); 387 388 // Try to fit it again 389 for (uint32_t i = 0; i < mCacheLines.size(); i++) { 390 bitmapFit = mCacheLines[i]->fitBitmap(glyph, &startX, &startY); 391 if (bitmapFit) { 392 break; 393 } 394 } 395 396 // if we still don't fit, something is wrong and we shouldn't draw 397 if (!bitmapFit) { 398 LOGE("Bitmap doesn't fit in cache. width, height = %i, %i", 399 (int) glyph.fWidth, (int) glyph.fHeight); 400 return false; 401 } 402 } 403 404 *retOriginX = startX; 405 *retOriginY = startY; 406 407 uint32_t endX = startX + glyph.fWidth; 408 uint32_t endY = startY + glyph.fHeight; 409 410 uint32_t cacheWidth = mCacheWidth; 411 412 uint8_t* cacheBuffer = mTextTexture; 413 uint8_t* bitmapBuffer = (uint8_t*) glyph.fImage; 414 unsigned int stride = glyph.rowBytes(); 415 416 uint32_t cacheX = 0, bX = 0, cacheY = 0, bY = 0; 417 for (cacheX = startX, bX = 0; cacheX < endX; cacheX++, bX++) { 418 for (cacheY = startY, bY = 0; cacheY < endY; cacheY++, bY++) { 419 uint8_t tempCol = bitmapBuffer[bY * stride + bX]; 420 cacheBuffer[cacheY * cacheWidth + cacheX] = mGammaTable[tempCol]; 421 } 422 } 423 424 return true; 425} 426 427void FontRenderer::initTextTexture() { 428 mTextTexture = new uint8_t[mCacheWidth * mCacheHeight]; 429 mUploadTexture = false; 430 431 glGenTextures(1, &mTextureId); 432 glBindTexture(GL_TEXTURE_2D, mTextureId); 433 glPixelStorei(GL_UNPACK_ALIGNMENT, 1); 434 // Initialize texture dimentions 435 glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, mCacheWidth, mCacheHeight, 0, 436 GL_ALPHA, GL_UNSIGNED_BYTE, 0); 437 438 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); 439 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); 440 441 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); 442 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE); 443 444 // Split up our cache texture into lines of certain widths 445 int nextLine = 0; 446 mCacheLines.push(new CacheTextureLine(mCacheWidth, 16, nextLine, 0)); 447 nextLine += mCacheLines.top()->mMaxHeight; 448 mCacheLines.push(new CacheTextureLine(mCacheWidth, 24, nextLine, 0)); 449 nextLine += mCacheLines.top()->mMaxHeight; 450 mCacheLines.push(new CacheTextureLine(mCacheWidth, 24, nextLine, 0)); 451 nextLine += mCacheLines.top()->mMaxHeight; 452 mCacheLines.push(new CacheTextureLine(mCacheWidth, 32, nextLine, 0)); 453 nextLine += mCacheLines.top()->mMaxHeight; 454 mCacheLines.push(new CacheTextureLine(mCacheWidth, 32, nextLine, 0)); 455 nextLine += mCacheLines.top()->mMaxHeight; 456 mCacheLines.push(new CacheTextureLine(mCacheWidth, 40, nextLine, 0)); 457 nextLine += mCacheLines.top()->mMaxHeight; 458 mCacheLines.push(new CacheTextureLine(mCacheWidth, mCacheHeight - nextLine, nextLine, 0)); 459} 460 461// Avoid having to reallocate memory and render quad by quad 462void FontRenderer::initVertexArrayBuffers() { 463 uint32_t numIndicies = mMaxNumberOfQuads * 6; 464 uint32_t indexBufferSizeBytes = numIndicies * sizeof(uint16_t); 465 uint16_t* indexBufferData = (uint16_t*) malloc(indexBufferSizeBytes); 466 467 // Four verts, two triangles , six indices per quad 468 for (uint32_t i = 0; i < mMaxNumberOfQuads; i++) { 469 int i6 = i * 6; 470 int i4 = i * 4; 471 472 indexBufferData[i6 + 0] = i4 + 0; 473 indexBufferData[i6 + 1] = i4 + 1; 474 indexBufferData[i6 + 2] = i4 + 2; 475 476 indexBufferData[i6 + 3] = i4 + 0; 477 indexBufferData[i6 + 4] = i4 + 2; 478 indexBufferData[i6 + 5] = i4 + 3; 479 } 480 481 glGenBuffers(1, &mIndexBufferID); 482 glBindBuffer(GL_ARRAY_BUFFER, mIndexBufferID); 483 glBufferData(GL_ARRAY_BUFFER, indexBufferSizeBytes, indexBufferData, GL_DYNAMIC_DRAW); 484 glBindBuffer(GL_ARRAY_BUFFER, 0); 485 486 free(indexBufferData); 487 488 uint32_t coordSize = 3; 489 uint32_t uvSize = 2; 490 uint32_t vertsPerQuad = 4; 491 uint32_t vertexBufferSize = mMaxNumberOfQuads * vertsPerQuad * coordSize * uvSize; 492 mTextMeshPtr = new float[vertexBufferSize]; 493} 494 495// We don't want to allocate anything unless we actually draw text 496void FontRenderer::checkInit() { 497 if (mInitialized) { 498 return; 499 } 500 501 initTextTexture(); 502 initVertexArrayBuffers(); 503 504 // We store a string with letters in a rough frequency of occurrence 505 mLatinPrecache = String16("eisarntolcdugpmhbyfvkwzxjq "); 506 mLatinPrecache += String16("EISARNTOLCDUGPMHBYFVKWZXJQ"); 507 mLatinPrecache += String16(",.?!()-+@;:`'"); 508 mLatinPrecache += String16("0123456789"); 509 510 mInitialized = true; 511} 512 513void FontRenderer::checkTextureUpdate() { 514 if (!mUploadTexture) { 515 return; 516 } 517 518 glBindTexture(GL_TEXTURE_2D, mTextureId); 519 520 // Iterate over all the cache lines and see which ones need to be updated 521 for (uint32_t i = 0; i < mCacheLines.size(); i++) { 522 CacheTextureLine* cl = mCacheLines[i]; 523 if(cl->mDirty) { 524 uint32_t xOffset = 0; 525 uint32_t yOffset = cl->mCurrentRow; 526 uint32_t width = mCacheWidth; 527 uint32_t height = cl->mMaxHeight; 528 void* textureData = mTextTexture + yOffset*width; 529 530 glTexSubImage2D(GL_TEXTURE_2D, 0, xOffset, yOffset, width, height, 531 GL_ALPHA, GL_UNSIGNED_BYTE, textureData); 532 533 cl->mDirty = false; 534 } 535 } 536 537 mUploadTexture = false; 538} 539 540void FontRenderer::issueDrawCommand() { 541 checkTextureUpdate(); 542 543 float* vtx = mTextMeshPtr; 544 float* tex = vtx + 3; 545 546 // position is slot 0 547 uint32_t slot = 0; 548 glVertexAttribPointer(slot, 3, GL_FLOAT, false, 20, vtx); 549 550 // texture0 is slot 1 551 slot = 1; 552 glVertexAttribPointer(slot, 2, GL_FLOAT, false, 20, tex); 553 554 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIndexBufferID); 555 glDrawElements(GL_TRIANGLES, mCurrentQuadIndex * 6, GL_UNSIGNED_SHORT, NULL); 556} 557 558void FontRenderer::appendMeshQuad(float x1, float y1, float z1, float u1, float v1, float x2, 559 float y2, float z2, float u2, float v2, float x3, float y3, float z3, float u3, float v3, 560 float x4, float y4, float z4, float u4, float v4) { 561 if (x1 > mClip->right || y1 < mClip->top || x2 < mClip->left || y4 > mClip->bottom) { 562 return; 563 } 564 565 const uint32_t vertsPerQuad = 4; 566 const uint32_t floatsPerVert = 5; 567 float* currentPos = mTextMeshPtr + mCurrentQuadIndex * vertsPerQuad * floatsPerVert; 568 569 (*currentPos++) = x1; 570 (*currentPos++) = y1; 571 (*currentPos++) = z1; 572 (*currentPos++) = u1; 573 (*currentPos++) = v1; 574 575 (*currentPos++) = x2; 576 (*currentPos++) = y2; 577 (*currentPos++) = z2; 578 (*currentPos++) = u2; 579 (*currentPos++) = v2; 580 581 (*currentPos++) = x3; 582 (*currentPos++) = y3; 583 (*currentPos++) = z3; 584 (*currentPos++) = u3; 585 (*currentPos++) = v3; 586 587 (*currentPos++) = x4; 588 (*currentPos++) = y4; 589 (*currentPos++) = z4; 590 (*currentPos++) = u4; 591 (*currentPos++) = v4; 592 593 mCurrentQuadIndex++; 594 595 if (mCurrentQuadIndex == mMaxNumberOfQuads) { 596 issueDrawCommand(); 597 mCurrentQuadIndex = 0; 598 } 599} 600 601uint32_t FontRenderer::getRemainingCacheCapacity() { 602 uint32_t remainingCapacity = 0; 603 float totalPixels = 0; 604 for(uint32_t i = 0; i < mCacheLines.size(); i ++) { 605 remainingCapacity += (mCacheLines[i]->mMaxWidth - mCacheLines[i]->mCurrentCol); 606 totalPixels += mCacheLines[i]->mMaxWidth; 607 } 608 remainingCapacity = (remainingCapacity * 100) / totalPixels; 609 return remainingCapacity; 610} 611 612void FontRenderer::precacheLatin(SkPaint* paint) { 613 // Remaining capacity is measured in % 614 uint32_t remainingCapacity = getRemainingCacheCapacity(); 615 uint32_t precacheIdx = 0; 616 while(remainingCapacity > 25 && precacheIdx < mLatinPrecache.size()) { 617 mCurrentFont->getCachedUTFChar(paint, (int32_t)mLatinPrecache[precacheIdx]); 618 remainingCapacity = getRemainingCacheCapacity(); 619 precacheIdx ++; 620 } 621} 622 623void FontRenderer::setFont(SkPaint* paint, uint32_t fontId, float fontSize) { 624 uint32_t currentNumFonts = mActiveFonts.size(); 625 mCurrentFont = Font::create(this, fontId, fontSize); 626 627 const float maxPrecacheFontSize = 40.0f; 628 bool isNewFont = currentNumFonts != mActiveFonts.size(); 629 630 if (isNewFont && fontSize <= maxPrecacheFontSize) { 631 precacheLatin(paint); 632 } 633} 634FontRenderer::DropShadow FontRenderer::renderDropShadow(SkPaint* paint, const char *text, 635 uint32_t startIndex, uint32_t len, int numGlyphs, uint32_t radius) { 636 checkInit(); 637 638 if (!mCurrentFont) { 639 DropShadow image; 640 image.width = 0; 641 image.height = 0; 642 image.image = NULL; 643 image.penX = 0; 644 image.penY = 0; 645 return image; 646 } 647 648 Rect bounds; 649 mCurrentFont->measureUTF(paint, text, startIndex, len, numGlyphs, &bounds); 650 uint32_t paddedWidth = (uint32_t) (bounds.right - bounds.left) + 2 * radius; 651 uint32_t paddedHeight = (uint32_t) (bounds.top - bounds.bottom) + 2 * radius; 652 uint8_t* dataBuffer = new uint8_t[paddedWidth * paddedHeight]; 653 for (uint32_t i = 0; i < paddedWidth * paddedHeight; i++) { 654 dataBuffer[i] = 0; 655 } 656 657 int penX = radius - bounds.left; 658 int penY = radius - bounds.bottom; 659 660 mCurrentFont->renderUTF(paint, text, startIndex, len, numGlyphs, penX, penY, 661 dataBuffer, paddedWidth, paddedHeight); 662 blurImage(dataBuffer, paddedWidth, paddedHeight, radius); 663 664 DropShadow image; 665 image.width = paddedWidth; 666 image.height = paddedHeight; 667 image.image = dataBuffer; 668 image.penX = penX; 669 image.penY = penY; 670 return image; 671} 672 673void FontRenderer::renderText(SkPaint* paint, const Rect* clip, const char *text, 674 uint32_t startIndex, uint32_t len, int numGlyphs, int x, int y) { 675 checkInit(); 676 677 if (!mCurrentFont) { 678 LOGE("No font set"); 679 return; 680 } 681 682 mClip = clip; 683 mCurrentFont->renderUTF(paint, text, startIndex, len, numGlyphs, x, y); 684 685 if (mCurrentQuadIndex != 0) { 686 issueDrawCommand(); 687 mCurrentQuadIndex = 0; 688 } 689} 690 691void FontRenderer::computeGaussianWeights(float* weights, int32_t radius) { 692 // Compute gaussian weights for the blur 693 // e is the euler's number 694 float e = 2.718281828459045f; 695 float pi = 3.1415926535897932f; 696 // g(x) = ( 1 / sqrt( 2 * pi ) * sigma) * e ^ ( -x^2 / 2 * sigma^2 ) 697 // x is of the form [-radius .. 0 .. radius] 698 // and sigma varies with radius. 699 // Based on some experimental radius values and sigma's 700 // we approximately fit sigma = f(radius) as 701 // sigma = radius * 0.3 + 0.6 702 // The larger the radius gets, the more our gaussian blur 703 // will resemble a box blur since with large sigma 704 // the gaussian curve begins to lose its shape 705 float sigma = 0.3f * (float)radius + 0.6f; 706 707 // Now compute the coefficints 708 // We will store some redundant values to save some math during 709 // the blur calculations 710 // precompute some values 711 float coeff1 = 1.0f / (sqrt( 2.0f * pi ) * sigma); 712 float coeff2 = - 1.0f / (2.0f * sigma * sigma); 713 714 float normalizeFactor = 0.0f; 715 for(int32_t r = -radius; r <= radius; r ++) { 716 float floatR = (float)r; 717 weights[r + radius] = coeff1 * pow(e, floatR * floatR * coeff2); 718 normalizeFactor += weights[r + radius]; 719 } 720 721 //Now we need to normalize the weights because all our coefficients need to add up to one 722 normalizeFactor = 1.0f / normalizeFactor; 723 for(int32_t r = -radius; r <= radius; r ++) { 724 weights[r + radius] *= normalizeFactor; 725 } 726} 727 728void FontRenderer::horizontalBlur(float* weights, int32_t radius, 729 const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) { 730 float blurredPixel = 0.0f; 731 float currentPixel = 0.0f; 732 733 for(int32_t y = 0; y < height; y ++) { 734 735 const uint8_t* input = source + y * width; 736 uint8_t* output = dest + y * width; 737 738 for(int32_t x = 0; x < width; x ++) { 739 blurredPixel = 0.0f; 740 const float* gPtr = weights; 741 // Optimization for non-border pixels 742 if ((x > radius) && (x < (width - radius))) { 743 const uint8_t *i = input + (x - radius); 744 for(int r = -radius; r <= radius; r ++) { 745 currentPixel = (float)(*i); 746 blurredPixel += currentPixel * gPtr[0]; 747 gPtr++; 748 i++; 749 } 750 } else { 751 for(int32_t r = -radius; r <= radius; r ++) { 752 // Stepping left and right away from the pixel 753 int validW = x + r; 754 if(validW < 0) { 755 validW = 0; 756 } 757 if(validW > width - 1) { 758 validW = width - 1; 759 } 760 761 currentPixel = (float)(input[validW]); 762 blurredPixel += currentPixel * gPtr[0]; 763 gPtr++; 764 } 765 } 766 *output = (uint8_t)blurredPixel; 767 output ++; 768 } 769 } 770} 771 772void FontRenderer::verticalBlur(float* weights, int32_t radius, 773 const uint8_t* source, uint8_t* dest, int32_t width, int32_t height) { 774 float blurredPixel = 0.0f; 775 float currentPixel = 0.0f; 776 777 for(int32_t y = 0; y < height; y ++) { 778 779 uint8_t* output = dest + y * width; 780 781 for(int32_t x = 0; x < width; x ++) { 782 blurredPixel = 0.0f; 783 const float* gPtr = weights; 784 const uint8_t* input = source + x; 785 // Optimization for non-border pixels 786 if ((y > radius) && (y < (height - radius))) { 787 const uint8_t *i = input + ((y - radius) * width); 788 for(int32_t r = -radius; r <= radius; r ++) { 789 currentPixel = (float)(*i); 790 blurredPixel += currentPixel * gPtr[0]; 791 gPtr++; 792 i += width; 793 } 794 } else { 795 for(int32_t r = -radius; r <= radius; r ++) { 796 int validH = y + r; 797 // Clamp to zero and width 798 if(validH < 0) { 799 validH = 0; 800 } 801 if(validH > height - 1) { 802 validH = height - 1; 803 } 804 805 const uint8_t *i = input + validH * width; 806 currentPixel = (float)(*i); 807 blurredPixel += currentPixel * gPtr[0]; 808 gPtr++; 809 } 810 } 811 *output = (uint8_t)blurredPixel; 812 output ++; 813 } 814 } 815} 816 817 818void FontRenderer::blurImage(uint8_t *image, int32_t width, int32_t height, int32_t radius) { 819 float *gaussian = new float[2 * radius + 1]; 820 computeGaussianWeights(gaussian, radius); 821 uint8_t* scratch = new uint8_t[width * height]; 822 horizontalBlur(gaussian, radius, image, scratch, width, height); 823 verticalBlur(gaussian, radius, scratch, image, width, height); 824 delete[] gaussian; 825 delete[] scratch; 826} 827 828}; // namespace uirenderer 829}; // namespace android 830