SkFontHost_FreeType.cpp revision 7a722f0ebf6acfd02899bc30a5529d0b23b3ffae
1 2/* 3 * Copyright 2006 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9#include "SkBitmap.h" 10#include "SkCanvas.h" 11#include "SkColorPriv.h" 12#include "SkDescriptor.h" 13#include "SkFDot6.h" 14#include "SkFloatingPoint.h" 15#include "SkFontHost.h" 16#include "SkFontHost_FreeType_common.h" 17#include "SkGlyph.h" 18#include "SkMask.h" 19#include "SkMaskGamma.h" 20#include "SkAdvancedTypefaceMetrics.h" 21#include "SkScalerContext.h" 22#include "SkStream.h" 23#include "SkString.h" 24#include "SkTemplates.h" 25#include "SkThread.h" 26 27#if defined(SK_CAN_USE_DLOPEN) 28#include <dlfcn.h> 29#endif 30#include <ft2build.h> 31#include FT_FREETYPE_H 32#include FT_OUTLINE_H 33#include FT_SIZES_H 34#include FT_TRUETYPE_TABLES_H 35#include FT_TYPE1_TABLES_H 36#include FT_BITMAP_H 37// In the past, FT_GlyphSlot_Own_Bitmap was defined in this header file. 38#include FT_SYNTHESIS_H 39#include FT_XFREE86_H 40#ifdef FT_LCD_FILTER_H 41#include FT_LCD_FILTER_H 42#endif 43 44#ifdef FT_ADVANCES_H 45#include FT_ADVANCES_H 46#endif 47 48#if 0 49// Also include the files by name for build tools which require this. 50#include <freetype/freetype.h> 51#include <freetype/ftoutln.h> 52#include <freetype/ftsizes.h> 53#include <freetype/tttables.h> 54#include <freetype/ftadvanc.h> 55#include <freetype/ftlcdfil.h> 56#include <freetype/ftbitmap.h> 57#include <freetype/ftsynth.h> 58#endif 59 60//#define ENABLE_GLYPH_SPEW // for tracing calls 61//#define DUMP_STRIKE_CREATION 62 63//#define SK_GAMMA_APPLY_TO_A8 64 65using namespace skia_advanced_typeface_metrics_utils; 66 67static bool isLCD(const SkScalerContext::Rec& rec) { 68 switch (rec.fMaskFormat) { 69 case SkMask::kLCD16_Format: 70 case SkMask::kLCD32_Format: 71 return true; 72 default: 73 return false; 74 } 75} 76 77////////////////////////////////////////////////////////////////////////// 78 79struct SkFaceRec; 80 81SK_DECLARE_STATIC_MUTEX(gFTMutex); 82static int gFTCount; 83static FT_Library gFTLibrary; 84static SkFaceRec* gFaceRecHead; 85static bool gLCDSupportValid; // true iff |gLCDSupport| has been set. 86static bool gLCDSupport; // true iff LCD is supported by the runtime. 87static int gLCDExtra; // number of extra pixels for filtering. 88 89///////////////////////////////////////////////////////////////////////// 90 91// FT_Library_SetLcdFilterWeights was introduced in FreeType 2.4.0. 92// The following platforms provide FreeType of at least 2.4.0. 93// Ubuntu >= 11.04 (previous deprecated April 2013) 94// Debian >= 6.0 (good) 95// OpenSuse >= 11.4 (previous deprecated January 2012 / Nov 2013 for Evergreen 11.2) 96// Fedora >= 14 (good) 97// Android >= Gingerbread (good) 98typedef FT_Error (*FT_Library_SetLcdFilterWeightsProc)(FT_Library, unsigned char*); 99 100// Caller must lock gFTMutex before calling this function. 101static bool InitFreetype() { 102 FT_Error err = FT_Init_FreeType(&gFTLibrary); 103 if (err) { 104 return false; 105 } 106 107 // Setup LCD filtering. This reduces color fringes for LCD smoothed glyphs. 108#ifdef FT_LCD_FILTER_H 109 // Use default { 0x10, 0x40, 0x70, 0x40, 0x10 }, as it adds up to 0x110, simulating ink spread. 110 // SetLcdFilter must be called before SetLcdFilterWeights. 111 err = FT_Library_SetLcdFilter(gFTLibrary, FT_LCD_FILTER_DEFAULT); 112 if (0 == err) { 113 gLCDSupport = true; 114 gLCDExtra = 2; //Using a filter adds one full pixel to each side. 115 116#ifdef SK_FONTHOST_FREETYPE_USE_NORMAL_LCD_FILTER 117 // This also adds to 0x110 simulating ink spread, but provides better results than default. 118 static unsigned char gGaussianLikeHeavyWeights[] = { 0x1A, 0x43, 0x56, 0x43, 0x1A, }; 119 120#if defined(SK_FONTHOST_FREETYPE_RUNTIME_VERSION) && \ 121 SK_FONTHOST_FREETYPE_RUNTIME_VERSION > 0x020400 122 err = FT_Library_SetLcdFilterWeights(gFTLibrary, gGaussianLikeHeavyWeights); 123#elif defined(SK_CAN_USE_DLOPEN) && SK_CAN_USE_DLOPEN == 1 124 //The FreeType library is already loaded, so symbols are available in process. 125 void* self = dlopen(NULL, RTLD_LAZY); 126 if (NULL != self) { 127 FT_Library_SetLcdFilterWeightsProc setLcdFilterWeights; 128 //The following cast is non-standard, but safe for POSIX. 129 *reinterpret_cast<void**>(&setLcdFilterWeights) = dlsym(self, "FT_Library_SetLcdFilterWeights"); 130 dlclose(self); 131 132 if (NULL != setLcdFilterWeights) { 133 err = setLcdFilterWeights(gFTLibrary, gGaussianLikeHeavyWeights); 134 } 135 } 136#endif 137#endif 138 } 139#else 140 gLCDSupport = false; 141#endif 142 gLCDSupportValid = true; 143 144 return true; 145} 146 147// Lazy, once, wrapper to ask the FreeType Library if it can support LCD text 148static bool is_lcd_supported() { 149 if (!gLCDSupportValid) { 150 SkAutoMutexAcquire ac(gFTMutex); 151 152 if (!gLCDSupportValid) { 153 InitFreetype(); 154 FT_Done_FreeType(gFTLibrary); 155 } 156 } 157 return gLCDSupport; 158} 159 160class SkScalerContext_FreeType : public SkScalerContext_FreeType_Base { 161public: 162 SkScalerContext_FreeType(const SkDescriptor* desc); 163 virtual ~SkScalerContext_FreeType(); 164 165 bool success() const { 166 return fFaceRec != NULL && 167 fFTSize != NULL && 168 fFace != NULL; 169 } 170 171protected: 172 virtual unsigned generateGlyphCount() SK_OVERRIDE; 173 virtual uint16_t generateCharToGlyph(SkUnichar uni) SK_OVERRIDE; 174 virtual void generateAdvance(SkGlyph* glyph) SK_OVERRIDE; 175 virtual void generateMetrics(SkGlyph* glyph) SK_OVERRIDE; 176 virtual void generateImage(const SkGlyph& glyph) SK_OVERRIDE; 177 virtual void generatePath(const SkGlyph& glyph, SkPath* path) SK_OVERRIDE; 178 virtual void generateFontMetrics(SkPaint::FontMetrics* mx, 179 SkPaint::FontMetrics* my) SK_OVERRIDE; 180 virtual SkUnichar generateGlyphToChar(uint16_t glyph) SK_OVERRIDE; 181 182private: 183 SkFaceRec* fFaceRec; 184 FT_Face fFace; // reference to shared face in gFaceRecHead 185 FT_Size fFTSize; // our own copy 186 SkFixed fScaleX, fScaleY; 187 FT_Matrix fMatrix22; 188 uint32_t fLoadGlyphFlags; 189 bool fDoLinearMetrics; 190 bool fLCDIsVert; 191 192 FT_Error setupSize(); 193 void getBBoxForCurrentGlyph(SkGlyph* glyph, FT_BBox* bbox, 194 bool snapToPixelBoundary = false); 195 // Caller must lock gFTMutex before calling this function. 196 void updateGlyphIfLCD(SkGlyph* glyph); 197}; 198 199/////////////////////////////////////////////////////////////////////////// 200/////////////////////////////////////////////////////////////////////////// 201 202#include "SkStream.h" 203 204struct SkFaceRec { 205 SkFaceRec* fNext; 206 FT_Face fFace; 207 FT_StreamRec fFTStream; 208 SkStream* fSkStream; 209 uint32_t fRefCnt; 210 uint32_t fFontID; 211 212 // assumes ownership of the stream, will call unref() when its done 213 SkFaceRec(SkStream* strm, uint32_t fontID); 214 ~SkFaceRec() { 215 fSkStream->unref(); 216 } 217}; 218 219extern "C" { 220 static unsigned long sk_stream_read(FT_Stream stream, 221 unsigned long offset, 222 unsigned char* buffer, 223 unsigned long count ) { 224 SkStream* str = (SkStream*)stream->descriptor.pointer; 225 226 if (count) { 227 if (!str->rewind()) { 228 return 0; 229 } else { 230 unsigned long ret; 231 if (offset) { 232 ret = str->read(NULL, offset); 233 if (ret != offset) { 234 return 0; 235 } 236 } 237 ret = str->read(buffer, count); 238 if (ret != count) { 239 return 0; 240 } 241 count = ret; 242 } 243 } 244 return count; 245 } 246 247 static void sk_stream_close( FT_Stream stream) {} 248} 249 250SkFaceRec::SkFaceRec(SkStream* strm, uint32_t fontID) 251 : fNext(NULL), fSkStream(strm), fRefCnt(1), fFontID(fontID) { 252// SkDEBUGF(("SkFaceRec: opening %s (%p)\n", key.c_str(), strm)); 253 254 sk_bzero(&fFTStream, sizeof(fFTStream)); 255 fFTStream.size = fSkStream->getLength(); 256 fFTStream.descriptor.pointer = fSkStream; 257 fFTStream.read = sk_stream_read; 258 fFTStream.close = sk_stream_close; 259} 260 261// Will return 0 on failure 262// Caller must lock gFTMutex before calling this function. 263static SkFaceRec* ref_ft_face(uint32_t fontID) { 264 SkFaceRec* rec = gFaceRecHead; 265 while (rec) { 266 if (rec->fFontID == fontID) { 267 SkASSERT(rec->fFace); 268 rec->fRefCnt += 1; 269 return rec; 270 } 271 rec = rec->fNext; 272 } 273 274 SkStream* strm = SkFontHost::OpenStream(fontID); 275 if (NULL == strm) { 276 SkDEBUGF(("SkFontHost::OpenStream failed opening %x\n", fontID)); 277 return 0; 278 } 279 280 // this passes ownership of strm to the rec 281 rec = SkNEW_ARGS(SkFaceRec, (strm, fontID)); 282 283 FT_Open_Args args; 284 memset(&args, 0, sizeof(args)); 285 const void* memoryBase = strm->getMemoryBase(); 286 287 if (NULL != memoryBase) { 288//printf("mmap(%s)\n", keyString.c_str()); 289 args.flags = FT_OPEN_MEMORY; 290 args.memory_base = (const FT_Byte*)memoryBase; 291 args.memory_size = strm->getLength(); 292 } else { 293//printf("fopen(%s)\n", keyString.c_str()); 294 args.flags = FT_OPEN_STREAM; 295 args.stream = &rec->fFTStream; 296 } 297 298 int face_index; 299 int length = SkFontHost::GetFileName(fontID, NULL, 0, &face_index); 300 FT_Error err = FT_Open_Face(gFTLibrary, &args, length ? face_index : 0, 301 &rec->fFace); 302 303 if (err) { // bad filename, try the default font 304 fprintf(stderr, "ERROR: unable to open font '%x'\n", fontID); 305 SkDELETE(rec); 306 return 0; 307 } else { 308 SkASSERT(rec->fFace); 309 //fprintf(stderr, "Opened font '%s'\n", filename.c_str()); 310 rec->fNext = gFaceRecHead; 311 gFaceRecHead = rec; 312 return rec; 313 } 314} 315 316// Caller must lock gFTMutex before calling this function. 317static void unref_ft_face(FT_Face face) { 318 SkFaceRec* rec = gFaceRecHead; 319 SkFaceRec* prev = NULL; 320 while (rec) { 321 SkFaceRec* next = rec->fNext; 322 if (rec->fFace == face) { 323 if (--rec->fRefCnt == 0) { 324 if (prev) { 325 prev->fNext = next; 326 } else { 327 gFaceRecHead = next; 328 } 329 FT_Done_Face(face); 330 SkDELETE(rec); 331 } 332 return; 333 } 334 prev = rec; 335 rec = next; 336 } 337 SkDEBUGFAIL("shouldn't get here, face not in list"); 338} 339 340/////////////////////////////////////////////////////////////////////////// 341 342// Work around for old versions of freetype. 343static FT_Error getAdvances(FT_Face face, FT_UInt start, FT_UInt count, 344 FT_Int32 loadFlags, FT_Fixed* advances) { 345#ifdef FT_ADVANCES_H 346 return FT_Get_Advances(face, start, count, loadFlags, advances); 347#else 348 if (!face || start >= face->num_glyphs || 349 start + count > face->num_glyphs || loadFlags != FT_LOAD_NO_SCALE) { 350 return 6; // "Invalid argument." 351 } 352 if (count == 0) 353 return 0; 354 355 for (int i = 0; i < count; i++) { 356 FT_Error err = FT_Load_Glyph(face, start + i, FT_LOAD_NO_SCALE); 357 if (err) 358 return err; 359 advances[i] = face->glyph->advance.x; 360 } 361 362 return 0; 363#endif 364} 365 366static bool canEmbed(FT_Face face) { 367#ifdef FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING 368 FT_UShort fsType = FT_Get_FSType_Flags(face); 369 return (fsType & (FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING | 370 FT_FSTYPE_BITMAP_EMBEDDING_ONLY)) == 0; 371#else 372 // No embedding is 0x2 and bitmap embedding only is 0x200. 373 TT_OS2* os2_table; 374 if ((os2_table = (TT_OS2*)FT_Get_Sfnt_Table(face, ft_sfnt_os2)) != NULL) { 375 return (os2_table->fsType & 0x202) == 0; 376 } 377 return false; // We tried, fail safe. 378#endif 379} 380 381static bool GetLetterCBox(FT_Face face, char letter, FT_BBox* bbox) { 382 const FT_UInt glyph_id = FT_Get_Char_Index(face, letter); 383 if (!glyph_id) 384 return false; 385 FT_Load_Glyph(face, glyph_id, FT_LOAD_NO_SCALE); 386 FT_Outline_Get_CBox(&face->glyph->outline, bbox); 387 return true; 388} 389 390static bool getWidthAdvance(FT_Face face, int gId, int16_t* data) { 391 FT_Fixed advance = 0; 392 if (getAdvances(face, gId, 1, FT_LOAD_NO_SCALE, &advance)) { 393 return false; 394 } 395 SkASSERT(data); 396 *data = advance; 397 return true; 398} 399 400static void populate_glyph_to_unicode(FT_Face& face, 401 SkTDArray<SkUnichar>* glyphToUnicode) { 402 // Check and see if we have Unicode cmaps. 403 for (int i = 0; i < face->num_charmaps; ++i) { 404 // CMaps known to support Unicode: 405 // Platform ID Encoding ID Name 406 // ----------- ----------- ----------------------------------- 407 // 0 0,1 Apple Unicode 408 // 0 3 Apple Unicode 2.0 (preferred) 409 // 3 1 Microsoft Unicode UCS-2 410 // 3 10 Microsoft Unicode UCS-4 (preferred) 411 // 412 // See Apple TrueType Reference Manual 413 // http://developer.apple.com/fonts/TTRefMan/RM06/Chap6cmap.html 414 // http://developer.apple.com/fonts/TTRefMan/RM06/Chap6name.html#ID 415 // Microsoft OpenType Specification 416 // http://www.microsoft.com/typography/otspec/cmap.htm 417 418 FT_UShort platformId = face->charmaps[i]->platform_id; 419 FT_UShort encodingId = face->charmaps[i]->encoding_id; 420 421 if (platformId != 0 && platformId != 3) { 422 continue; 423 } 424 if (platformId == 3 && encodingId != 1 && encodingId != 10) { 425 continue; 426 } 427 bool preferredMap = ((platformId == 3 && encodingId == 10) || 428 (platformId == 0 && encodingId == 3)); 429 430 FT_Set_Charmap(face, face->charmaps[i]); 431 if (glyphToUnicode->isEmpty()) { 432 glyphToUnicode->setCount(face->num_glyphs); 433 memset(glyphToUnicode->begin(), 0, 434 sizeof(SkUnichar) * face->num_glyphs); 435 } 436 437 // Iterate through each cmap entry. 438 FT_UInt glyphIndex; 439 for (SkUnichar charCode = FT_Get_First_Char(face, &glyphIndex); 440 glyphIndex != 0; 441 charCode = FT_Get_Next_Char(face, charCode, &glyphIndex)) { 442 if (charCode && 443 ((*glyphToUnicode)[glyphIndex] == 0 || preferredMap)) { 444 (*glyphToUnicode)[glyphIndex] = charCode; 445 } 446 } 447 } 448} 449 450// static 451SkAdvancedTypefaceMetrics* SkFontHost::GetAdvancedTypefaceMetrics( 452 uint32_t fontID, 453 SkAdvancedTypefaceMetrics::PerGlyphInfo perGlyphInfo, 454 const uint32_t* glyphIDs, 455 uint32_t glyphIDsCount) { 456#if defined(SK_BUILD_FOR_MAC) 457 return NULL; 458#else 459 SkAutoMutexAcquire ac(gFTMutex); 460 FT_Library libInit = NULL; 461 if (gFTCount == 0) { 462 if (!InitFreetype()) 463 sk_throw(); 464 libInit = gFTLibrary; 465 } 466 SkAutoTCallIProc<struct FT_LibraryRec_, FT_Done_FreeType> ftLib(libInit); 467 SkFaceRec* rec = ref_ft_face(fontID); 468 if (NULL == rec) 469 return NULL; 470 FT_Face face = rec->fFace; 471 472 SkAdvancedTypefaceMetrics* info = new SkAdvancedTypefaceMetrics; 473 info->fFontName.set(FT_Get_Postscript_Name(face)); 474 info->fMultiMaster = FT_HAS_MULTIPLE_MASTERS(face); 475 info->fLastGlyphID = face->num_glyphs - 1; 476 info->fEmSize = 1000; 477 478 bool cid = false; 479 const char* fontType = FT_Get_X11_Font_Format(face); 480 if (strcmp(fontType, "Type 1") == 0) { 481 info->fType = SkAdvancedTypefaceMetrics::kType1_Font; 482 } else if (strcmp(fontType, "CID Type 1") == 0) { 483 info->fType = SkAdvancedTypefaceMetrics::kType1CID_Font; 484 cid = true; 485 } else if (strcmp(fontType, "CFF") == 0) { 486 info->fType = SkAdvancedTypefaceMetrics::kCFF_Font; 487 } else if (strcmp(fontType, "TrueType") == 0) { 488 info->fType = SkAdvancedTypefaceMetrics::kTrueType_Font; 489 cid = true; 490 TT_Header* ttHeader; 491 if ((ttHeader = (TT_Header*)FT_Get_Sfnt_Table(face, 492 ft_sfnt_head)) != NULL) { 493 info->fEmSize = ttHeader->Units_Per_EM; 494 } 495 } 496 497 info->fStyle = 0; 498 if (FT_IS_FIXED_WIDTH(face)) 499 info->fStyle |= SkAdvancedTypefaceMetrics::kFixedPitch_Style; 500 if (face->style_flags & FT_STYLE_FLAG_ITALIC) 501 info->fStyle |= SkAdvancedTypefaceMetrics::kItalic_Style; 502 // We should set either Symbolic or Nonsymbolic; Nonsymbolic if the font's 503 // character set is a subset of 'Adobe standard Latin.' 504 info->fStyle |= SkAdvancedTypefaceMetrics::kSymbolic_Style; 505 506 PS_FontInfoRec ps_info; 507 TT_Postscript* tt_info; 508 if (FT_Get_PS_Font_Info(face, &ps_info) == 0) { 509 info->fItalicAngle = ps_info.italic_angle; 510 } else if ((tt_info = 511 (TT_Postscript*)FT_Get_Sfnt_Table(face, 512 ft_sfnt_post)) != NULL) { 513 info->fItalicAngle = SkFixedToScalar(tt_info->italicAngle); 514 } else { 515 info->fItalicAngle = 0; 516 } 517 518 info->fAscent = face->ascender; 519 info->fDescent = face->descender; 520 521 // Figure out a good guess for StemV - Min width of i, I, !, 1. 522 // This probably isn't very good with an italic font. 523 int16_t min_width = SHRT_MAX; 524 info->fStemV = 0; 525 char stem_chars[] = {'i', 'I', '!', '1'}; 526 for (size_t i = 0; i < SK_ARRAY_COUNT(stem_chars); i++) { 527 FT_BBox bbox; 528 if (GetLetterCBox(face, stem_chars[i], &bbox)) { 529 int16_t width = bbox.xMax - bbox.xMin; 530 if (width > 0 && width < min_width) { 531 min_width = width; 532 info->fStemV = min_width; 533 } 534 } 535 } 536 537 TT_PCLT* pclt_info; 538 TT_OS2* os2_table; 539 if ((pclt_info = (TT_PCLT*)FT_Get_Sfnt_Table(face, ft_sfnt_pclt)) != NULL) { 540 info->fCapHeight = pclt_info->CapHeight; 541 uint8_t serif_style = pclt_info->SerifStyle & 0x3F; 542 if (serif_style >= 2 && serif_style <= 6) 543 info->fStyle |= SkAdvancedTypefaceMetrics::kSerif_Style; 544 else if (serif_style >= 9 && serif_style <= 12) 545 info->fStyle |= SkAdvancedTypefaceMetrics::kScript_Style; 546 } else if ((os2_table = 547 (TT_OS2*)FT_Get_Sfnt_Table(face, ft_sfnt_os2)) != NULL) { 548 info->fCapHeight = os2_table->sCapHeight; 549 } else { 550 // Figure out a good guess for CapHeight: average the height of M and X. 551 FT_BBox m_bbox, x_bbox; 552 bool got_m, got_x; 553 got_m = GetLetterCBox(face, 'M', &m_bbox); 554 got_x = GetLetterCBox(face, 'X', &x_bbox); 555 if (got_m && got_x) { 556 info->fCapHeight = (m_bbox.yMax - m_bbox.yMin + x_bbox.yMax - 557 x_bbox.yMin) / 2; 558 } else if (got_m && !got_x) { 559 info->fCapHeight = m_bbox.yMax - m_bbox.yMin; 560 } else if (!got_m && got_x) { 561 info->fCapHeight = x_bbox.yMax - x_bbox.yMin; 562 } 563 } 564 565 info->fBBox = SkIRect::MakeLTRB(face->bbox.xMin, face->bbox.yMax, 566 face->bbox.xMax, face->bbox.yMin); 567 568 if (!canEmbed(face) || !FT_IS_SCALABLE(face) || 569 info->fType == SkAdvancedTypefaceMetrics::kOther_Font) { 570 perGlyphInfo = SkAdvancedTypefaceMetrics::kNo_PerGlyphInfo; 571 } 572 573 if (perGlyphInfo & SkAdvancedTypefaceMetrics::kHAdvance_PerGlyphInfo) { 574 if (FT_IS_FIXED_WIDTH(face)) { 575 appendRange(&info->fGlyphWidths, 0); 576 int16_t advance = face->max_advance_width; 577 info->fGlyphWidths->fAdvance.append(1, &advance); 578 finishRange(info->fGlyphWidths.get(), 0, 579 SkAdvancedTypefaceMetrics::WidthRange::kDefault); 580 } else if (!cid) { 581 appendRange(&info->fGlyphWidths, 0); 582 // So as to not blow out the stack, get advances in batches. 583 for (int gID = 0; gID < face->num_glyphs; gID += 128) { 584 FT_Fixed advances[128]; 585 int advanceCount = 128; 586 if (gID + advanceCount > face->num_glyphs) 587 advanceCount = face->num_glyphs - gID + 1; 588 getAdvances(face, gID, advanceCount, FT_LOAD_NO_SCALE, 589 advances); 590 for (int i = 0; i < advanceCount; i++) { 591 int16_t advance = advances[i]; 592 info->fGlyphWidths->fAdvance.append(1, &advance); 593 } 594 } 595 finishRange(info->fGlyphWidths.get(), face->num_glyphs - 1, 596 SkAdvancedTypefaceMetrics::WidthRange::kRange); 597 } else { 598 info->fGlyphWidths.reset( 599 getAdvanceData(face, 600 face->num_glyphs, 601 glyphIDs, 602 glyphIDsCount, 603 &getWidthAdvance)); 604 } 605 } 606 607 if (perGlyphInfo & SkAdvancedTypefaceMetrics::kVAdvance_PerGlyphInfo && 608 FT_HAS_VERTICAL(face)) { 609 SkASSERT(false); // Not implemented yet. 610 } 611 612 if (perGlyphInfo & SkAdvancedTypefaceMetrics::kGlyphNames_PerGlyphInfo && 613 info->fType == SkAdvancedTypefaceMetrics::kType1_Font) { 614 // Postscript fonts may contain more than 255 glyphs, so we end up 615 // using multiple font descriptions with a glyph ordering. Record 616 // the name of each glyph. 617 info->fGlyphNames.reset( 618 new SkAutoTArray<SkString>(face->num_glyphs)); 619 for (int gID = 0; gID < face->num_glyphs; gID++) { 620 char glyphName[128]; // PS limit for names is 127 bytes. 621 FT_Get_Glyph_Name(face, gID, glyphName, 128); 622 info->fGlyphNames->get()[gID].set(glyphName); 623 } 624 } 625 626 if (perGlyphInfo & SkAdvancedTypefaceMetrics::kToUnicode_PerGlyphInfo && 627 info->fType != SkAdvancedTypefaceMetrics::kType1_Font && 628 face->num_charmaps) { 629 populate_glyph_to_unicode(face, &(info->fGlyphToUnicode)); 630 } 631 632 if (!canEmbed(face)) 633 info->fType = SkAdvancedTypefaceMetrics::kNotEmbeddable_Font; 634 635 unref_ft_face(face); 636 return info; 637#endif 638} 639 640/////////////////////////////////////////////////////////////////////////// 641 642#define BLACK_LUMINANCE_LIMIT 0x40 643#define WHITE_LUMINANCE_LIMIT 0xA0 644 645static bool bothZero(SkScalar a, SkScalar b) { 646 return 0 == a && 0 == b; 647} 648 649// returns false if there is any non-90-rotation or skew 650static bool isAxisAligned(const SkScalerContext::Rec& rec) { 651 return 0 == rec.fPreSkewX && 652 (bothZero(rec.fPost2x2[0][1], rec.fPost2x2[1][0]) || 653 bothZero(rec.fPost2x2[0][0], rec.fPost2x2[1][1])); 654} 655 656void SkFontHost::FilterRec(SkScalerContext::Rec* rec, SkTypeface*) { 657 //BOGUS: http://code.google.com/p/chromium/issues/detail?id=121119 658 //Cap the requested size as larger sizes give bogus values. 659 //Remove when http://code.google.com/p/skia/issues/detail?id=554 is fixed. 660 if (rec->fTextSize > SkIntToScalar(1 << 14)) { 661 rec->fTextSize = SkIntToScalar(1 << 14); 662 } 663 664 if (!is_lcd_supported() && isLCD(*rec)) { 665 // If the runtime Freetype library doesn't support LCD mode, we disable 666 // it here. 667 rec->fMaskFormat = SkMask::kA8_Format; 668 } 669 670 SkPaint::Hinting h = rec->getHinting(); 671 if (SkPaint::kFull_Hinting == h && !isLCD(*rec)) { 672 // collapse full->normal hinting if we're not doing LCD 673 h = SkPaint::kNormal_Hinting; 674 } 675 if ((rec->fFlags & SkScalerContext::kSubpixelPositioning_Flag)) { 676 if (SkPaint::kNo_Hinting != h) { 677 h = SkPaint::kSlight_Hinting; 678 } 679 } 680 681#ifndef SK_IGNORE_ROTATED_FREETYPE_FIX 682 // rotated text looks bad with hinting, so we disable it as needed 683 if (!isAxisAligned(*rec)) { 684 h = SkPaint::kNo_Hinting; 685 } 686#endif 687 rec->setHinting(h); 688 689#ifndef SK_GAMMA_APPLY_TO_A8 690 if (!isLCD(*rec)) { 691 rec->ignorePreBlend(); 692 } 693#endif 694} 695 696#ifdef SK_BUILD_FOR_ANDROID 697uint32_t SkFontHost::GetUnitsPerEm(SkFontID fontID) { 698 SkAutoMutexAcquire ac(gFTMutex); 699 SkFaceRec *rec = ref_ft_face(fontID); 700 uint16_t unitsPerEm = 0; 701 702 if (rec != NULL && rec->fFace != NULL) { 703 unitsPerEm = rec->fFace->units_per_EM; 704 unref_ft_face(rec->fFace); 705 } 706 707 return (uint32_t)unitsPerEm; 708} 709#endif 710 711SkScalerContext_FreeType::SkScalerContext_FreeType(const SkDescriptor* desc) 712 : SkScalerContext_FreeType_Base(desc) { 713 SkAutoMutexAcquire ac(gFTMutex); 714 715 if (gFTCount == 0) { 716 if (!InitFreetype()) { 717 sk_throw(); 718 } 719 } 720 ++gFTCount; 721 722 // load the font file 723 fFTSize = NULL; 724 fFace = NULL; 725 fFaceRec = ref_ft_face(fRec.fFontID); 726 if (NULL == fFaceRec) { 727 return; 728 } 729 fFace = fFaceRec->fFace; 730 731 // compute our factors from the record 732 733 SkMatrix m; 734 735 fRec.getSingleMatrix(&m); 736 737#ifdef DUMP_STRIKE_CREATION 738 SkString keyString; 739 SkFontHost::GetDescriptorKeyString(desc, &keyString); 740 printf("========== strike [%g %g %g] [%g %g %g %g] hints %d format %d %s\n", SkScalarToFloat(fRec.fTextSize), 741 SkScalarToFloat(fRec.fPreScaleX), SkScalarToFloat(fRec.fPreSkewX), 742 SkScalarToFloat(fRec.fPost2x2[0][0]), SkScalarToFloat(fRec.fPost2x2[0][1]), 743 SkScalarToFloat(fRec.fPost2x2[1][0]), SkScalarToFloat(fRec.fPost2x2[1][1]), 744 fRec.getHinting(), fRec.fMaskFormat, keyString.c_str()); 745#endif 746 747 // now compute our scale factors 748 SkScalar sx = m.getScaleX(); 749 SkScalar sy = m.getScaleY(); 750 751 if (m.getSkewX() || m.getSkewY() || sx < 0 || sy < 0) { 752 // sort of give up on hinting 753 sx = SkMaxScalar(SkScalarAbs(sx), SkScalarAbs(m.getSkewX())); 754 sy = SkMaxScalar(SkScalarAbs(m.getSkewY()), SkScalarAbs(sy)); 755 sx = sy = SkScalarAve(sx, sy); 756 757 SkScalar inv = SkScalarInvert(sx); 758 759 // flip the skew elements to go from our Y-down system to FreeType's 760 fMatrix22.xx = SkScalarToFixed(SkScalarMul(m.getScaleX(), inv)); 761 fMatrix22.xy = -SkScalarToFixed(SkScalarMul(m.getSkewX(), inv)); 762 fMatrix22.yx = -SkScalarToFixed(SkScalarMul(m.getSkewY(), inv)); 763 fMatrix22.yy = SkScalarToFixed(SkScalarMul(m.getScaleY(), inv)); 764 } else { 765 fMatrix22.xx = fMatrix22.yy = SK_Fixed1; 766 fMatrix22.xy = fMatrix22.yx = 0; 767 } 768 769#ifdef SK_SUPPORT_HINTING_SCALE_FACTOR 770 if (fRec.getHinting() == SkPaint::kNo_Hinting) { 771 fScaleX = SkScalarToFixed(sx); 772 fScaleY = SkScalarToFixed(sy); 773 } else { 774 SkScalar hintingScaleFactor = fRec.fHintingScaleFactor; 775 776 fScaleX = SkScalarToFixed(sx / hintingScaleFactor); 777 fScaleY = SkScalarToFixed(sy / hintingScaleFactor); 778 779 fMatrix22.xx *= hintingScaleFactor; 780 fMatrix22.xy *= hintingScaleFactor; 781 fMatrix22.yx *= hintingScaleFactor; 782 fMatrix22.yy *= hintingScaleFactor; 783 } 784#else 785 fScaleX = SkScalarToFixed(sx); 786 fScaleY = SkScalarToFixed(sy); 787#endif 788 789 fLCDIsVert = SkToBool(fRec.fFlags & SkScalerContext::kLCD_Vertical_Flag); 790 791 // compute the flags we send to Load_Glyph 792 { 793 FT_Int32 loadFlags = FT_LOAD_DEFAULT; 794 bool linearMetrics = SkToBool(fRec.fFlags & SkScalerContext::kSubpixelPositioning_Flag); 795 796 if (SkMask::kBW_Format == fRec.fMaskFormat) { 797 // See http://code.google.com/p/chromium/issues/detail?id=43252#c24 798 loadFlags = FT_LOAD_TARGET_MONO; 799 if (fRec.getHinting() == SkPaint::kNo_Hinting) { 800 loadFlags = FT_LOAD_NO_HINTING; 801 linearMetrics = true; 802 } 803 } else { 804 switch (fRec.getHinting()) { 805 case SkPaint::kNo_Hinting: 806 loadFlags = FT_LOAD_NO_HINTING; 807 linearMetrics = true; 808 break; 809 case SkPaint::kSlight_Hinting: 810 loadFlags = FT_LOAD_TARGET_LIGHT; // This implies FORCE_AUTOHINT 811 break; 812 case SkPaint::kNormal_Hinting: 813 if (fRec.fFlags & SkScalerContext::kAutohinting_Flag) 814 loadFlags = FT_LOAD_FORCE_AUTOHINT; 815 else 816 loadFlags = FT_LOAD_NO_AUTOHINT; 817 break; 818 case SkPaint::kFull_Hinting: 819 if (fRec.fFlags & SkScalerContext::kAutohinting_Flag) { 820 loadFlags = FT_LOAD_FORCE_AUTOHINT; 821 break; 822 } 823 loadFlags = FT_LOAD_TARGET_NORMAL; 824 if (isLCD(fRec)) { 825 if (fLCDIsVert) { 826 loadFlags = FT_LOAD_TARGET_LCD_V; 827 } else { 828 loadFlags = FT_LOAD_TARGET_LCD; 829 } 830 } 831 break; 832 default: 833 SkDebugf("---------- UNKNOWN hinting %d\n", fRec.getHinting()); 834 break; 835 } 836 } 837 838 if ((fRec.fFlags & SkScalerContext::kEmbeddedBitmapText_Flag) == 0) { 839 loadFlags |= FT_LOAD_NO_BITMAP; 840 } 841 842 // Always using FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH to get correct 843 // advances, as fontconfig and cairo do. 844 // See http://code.google.com/p/skia/issues/detail?id=222. 845 loadFlags |= FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH; 846 847 // Use vertical layout if requested. 848 if (fRec.fFlags & SkScalerContext::kVertical_Flag) { 849 loadFlags |= FT_LOAD_VERTICAL_LAYOUT; 850 } 851 852 fLoadGlyphFlags = loadFlags; 853 fDoLinearMetrics = linearMetrics; 854 } 855 856 // now create the FT_Size 857 858 { 859 FT_Error err; 860 861 err = FT_New_Size(fFace, &fFTSize); 862 if (err != 0) { 863 SkDEBUGF(("SkScalerContext_FreeType::FT_New_Size(%x): FT_Set_Char_Size(0x%x, 0x%x) returned 0x%x\n", 864 fFaceRec->fFontID, fScaleX, fScaleY, err)); 865 fFace = NULL; 866 return; 867 } 868 869 err = FT_Activate_Size(fFTSize); 870 if (err != 0) { 871 SkDEBUGF(("SkScalerContext_FreeType::FT_Activate_Size(%x, 0x%x, 0x%x) returned 0x%x\n", 872 fFaceRec->fFontID, fScaleX, fScaleY, err)); 873 fFTSize = NULL; 874 } 875 876 err = FT_Set_Char_Size( fFace, 877 SkFixedToFDot6(fScaleX), SkFixedToFDot6(fScaleY), 878 72, 72); 879 if (err != 0) { 880 SkDEBUGF(("SkScalerContext_FreeType::FT_Set_Char_Size(%x, 0x%x, 0x%x) returned 0x%x\n", 881 fFaceRec->fFontID, fScaleX, fScaleY, err)); 882 fFace = NULL; 883 return; 884 } 885 886 FT_Set_Transform( fFace, &fMatrix22, NULL); 887 } 888} 889 890SkScalerContext_FreeType::~SkScalerContext_FreeType() { 891 SkAutoMutexAcquire ac(gFTMutex); 892 893 if (fFTSize != NULL) { 894 FT_Done_Size(fFTSize); 895 } 896 897 if (fFace != NULL) { 898 unref_ft_face(fFace); 899 } 900 if (--gFTCount == 0) { 901// SkDEBUGF(("FT_Done_FreeType\n")); 902 FT_Done_FreeType(gFTLibrary); 903 SkDEBUGCODE(gFTLibrary = NULL;) 904 } 905} 906 907/* We call this before each use of the fFace, since we may be sharing 908 this face with other context (at different sizes). 909*/ 910FT_Error SkScalerContext_FreeType::setupSize() { 911 FT_Error err = FT_Activate_Size(fFTSize); 912 913 if (err != 0) { 914 SkDEBUGF(("SkScalerContext_FreeType::FT_Activate_Size(%x, 0x%x, 0x%x) returned 0x%x\n", 915 fFaceRec->fFontID, fScaleX, fScaleY, err)); 916 fFTSize = NULL; 917 } else { 918 // seems we need to reset this every time (not sure why, but without it 919 // I get random italics from some other fFTSize) 920 FT_Set_Transform( fFace, &fMatrix22, NULL); 921 } 922 return err; 923} 924 925unsigned SkScalerContext_FreeType::generateGlyphCount() { 926 return fFace->num_glyphs; 927} 928 929uint16_t SkScalerContext_FreeType::generateCharToGlyph(SkUnichar uni) { 930 return SkToU16(FT_Get_Char_Index( fFace, uni )); 931} 932 933SkUnichar SkScalerContext_FreeType::generateGlyphToChar(uint16_t glyph) { 934 // iterate through each cmap entry, looking for matching glyph indices 935 FT_UInt glyphIndex; 936 SkUnichar charCode = FT_Get_First_Char( fFace, &glyphIndex ); 937 938 while (glyphIndex != 0) { 939 if (glyphIndex == glyph) { 940 return charCode; 941 } 942 charCode = FT_Get_Next_Char( fFace, charCode, &glyphIndex ); 943 } 944 945 return 0; 946} 947 948void SkScalerContext_FreeType::generateAdvance(SkGlyph* glyph) { 949#ifdef FT_ADVANCES_H 950 /* unhinted and light hinted text have linearly scaled advances 951 * which are very cheap to compute with some font formats... 952 */ 953 if (fDoLinearMetrics) { 954 SkAutoMutexAcquire ac(gFTMutex); 955 956 if (this->setupSize()) { 957 glyph->zeroMetrics(); 958 return; 959 } 960 961 FT_Error error; 962 FT_Fixed advance; 963 964 error = FT_Get_Advance( fFace, glyph->getGlyphID(fBaseGlyphCount), 965 fLoadGlyphFlags | FT_ADVANCE_FLAG_FAST_ONLY, 966 &advance ); 967 if (0 == error) { 968 glyph->fRsbDelta = 0; 969 glyph->fLsbDelta = 0; 970 glyph->fAdvanceX = SkFixedMul(fMatrix22.xx, advance); 971 glyph->fAdvanceY = - SkFixedMul(fMatrix22.yx, advance); 972 return; 973 } 974 } 975#endif /* FT_ADVANCES_H */ 976 /* otherwise, we need to load/hint the glyph, which is slower */ 977 this->generateMetrics(glyph); 978 return; 979} 980 981void SkScalerContext_FreeType::getBBoxForCurrentGlyph(SkGlyph* glyph, 982 FT_BBox* bbox, 983 bool snapToPixelBoundary) { 984 985 FT_Outline_Get_CBox(&fFace->glyph->outline, bbox); 986 987 if (fRec.fFlags & SkScalerContext::kSubpixelPositioning_Flag) { 988 int dx = SkFixedToFDot6(glyph->getSubXFixed()); 989 int dy = SkFixedToFDot6(glyph->getSubYFixed()); 990 // negate dy since freetype-y-goes-up and skia-y-goes-down 991 bbox->xMin += dx; 992 bbox->yMin -= dy; 993 bbox->xMax += dx; 994 bbox->yMax -= dy; 995 } 996 997 // outset the box to integral boundaries 998 if (snapToPixelBoundary) { 999 bbox->xMin &= ~63; 1000 bbox->yMin &= ~63; 1001 bbox->xMax = (bbox->xMax + 63) & ~63; 1002 bbox->yMax = (bbox->yMax + 63) & ~63; 1003 } 1004 1005 // Must come after snapToPixelBoundary so that the width and height are 1006 // consistent. Otherwise asserts will fire later on when generating the 1007 // glyph image. 1008 if (fRec.fFlags & SkScalerContext::kVertical_Flag) { 1009 FT_Vector vector; 1010 vector.x = fFace->glyph->metrics.vertBearingX - fFace->glyph->metrics.horiBearingX; 1011 vector.y = -fFace->glyph->metrics.vertBearingY - fFace->glyph->metrics.horiBearingY; 1012 FT_Vector_Transform(&vector, &fMatrix22); 1013 bbox->xMin += vector.x; 1014 bbox->xMax += vector.x; 1015 bbox->yMin += vector.y; 1016 bbox->yMax += vector.y; 1017 } 1018} 1019 1020void SkScalerContext_FreeType::updateGlyphIfLCD(SkGlyph* glyph) { 1021 if (isLCD(fRec)) { 1022 if (fLCDIsVert) { 1023 glyph->fHeight += gLCDExtra; 1024 glyph->fTop -= gLCDExtra >> 1; 1025 } else { 1026 glyph->fWidth += gLCDExtra; 1027 glyph->fLeft -= gLCDExtra >> 1; 1028 } 1029 } 1030} 1031 1032void SkScalerContext_FreeType::generateMetrics(SkGlyph* glyph) { 1033 SkAutoMutexAcquire ac(gFTMutex); 1034 1035 glyph->fRsbDelta = 0; 1036 glyph->fLsbDelta = 0; 1037 1038 FT_Error err; 1039 1040 if (this->setupSize()) { 1041 goto ERROR; 1042 } 1043 1044 err = FT_Load_Glyph( fFace, glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags ); 1045 if (err != 0) { 1046#if 0 1047 SkDEBUGF(("SkScalerContext_FreeType::generateMetrics(%x): FT_Load_Glyph(glyph:%d flags:%x) returned 0x%x\n", 1048 fFaceRec->fFontID, glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags, err)); 1049#endif 1050 ERROR: 1051 glyph->zeroMetrics(); 1052 return; 1053 } 1054 1055 switch ( fFace->glyph->format ) { 1056 case FT_GLYPH_FORMAT_OUTLINE: { 1057 FT_BBox bbox; 1058 1059 if (0 == fFace->glyph->outline.n_contours) { 1060 glyph->fWidth = 0; 1061 glyph->fHeight = 0; 1062 glyph->fTop = 0; 1063 glyph->fLeft = 0; 1064 break; 1065 } 1066 1067 if (fRec.fFlags & kEmbolden_Flag) { 1068 emboldenOutline(fFace, &fFace->glyph->outline); 1069 } 1070 1071 getBBoxForCurrentGlyph(glyph, &bbox, true); 1072 1073 glyph->fWidth = SkToU16(SkFDot6Floor(bbox.xMax - bbox.xMin)); 1074 glyph->fHeight = SkToU16(SkFDot6Floor(bbox.yMax - bbox.yMin)); 1075 glyph->fTop = -SkToS16(SkFDot6Floor(bbox.yMax)); 1076 glyph->fLeft = SkToS16(SkFDot6Floor(bbox.xMin)); 1077 1078 updateGlyphIfLCD(glyph); 1079 1080 break; 1081 } 1082 1083 case FT_GLYPH_FORMAT_BITMAP: 1084 if (fRec.fFlags & kEmbolden_Flag) { 1085 FT_GlyphSlot_Own_Bitmap(fFace->glyph); 1086 FT_Bitmap_Embolden(gFTLibrary, &fFace->glyph->bitmap, kBitmapEmboldenStrength, 0); 1087 } 1088 1089 if (fRec.fFlags & SkScalerContext::kVertical_Flag) { 1090 FT_Vector vector; 1091 vector.x = fFace->glyph->metrics.vertBearingX - fFace->glyph->metrics.horiBearingX; 1092 vector.y = -fFace->glyph->metrics.vertBearingY - fFace->glyph->metrics.horiBearingY; 1093 FT_Vector_Transform(&vector, &fMatrix22); 1094 fFace->glyph->bitmap_left += SkFDot6Floor(vector.x); 1095 fFace->glyph->bitmap_top += SkFDot6Floor(vector.y); 1096 } 1097 1098 glyph->fWidth = SkToU16(fFace->glyph->bitmap.width); 1099 glyph->fHeight = SkToU16(fFace->glyph->bitmap.rows); 1100 glyph->fTop = -SkToS16(fFace->glyph->bitmap_top); 1101 glyph->fLeft = SkToS16(fFace->glyph->bitmap_left); 1102 break; 1103 1104 default: 1105 SkDEBUGFAIL("unknown glyph format"); 1106 goto ERROR; 1107 } 1108 1109 if (fRec.fFlags & SkScalerContext::kVertical_Flag) { 1110 if (fDoLinearMetrics) { 1111 glyph->fAdvanceX = -SkFixedMul(fMatrix22.xy, fFace->glyph->linearVertAdvance); 1112 glyph->fAdvanceY = SkFixedMul(fMatrix22.yy, fFace->glyph->linearVertAdvance); 1113 } else { 1114 glyph->fAdvanceX = -SkFDot6ToFixed(fFace->glyph->advance.x); 1115 glyph->fAdvanceY = SkFDot6ToFixed(fFace->glyph->advance.y); 1116 } 1117 } else { 1118 if (fDoLinearMetrics) { 1119 glyph->fAdvanceX = SkFixedMul(fMatrix22.xx, fFace->glyph->linearHoriAdvance); 1120 glyph->fAdvanceY = -SkFixedMul(fMatrix22.yx, fFace->glyph->linearHoriAdvance); 1121 } else { 1122 glyph->fAdvanceX = SkFDot6ToFixed(fFace->glyph->advance.x); 1123 glyph->fAdvanceY = -SkFDot6ToFixed(fFace->glyph->advance.y); 1124 1125 if (fRec.fFlags & kDevKernText_Flag) { 1126 glyph->fRsbDelta = SkToS8(fFace->glyph->rsb_delta); 1127 glyph->fLsbDelta = SkToS8(fFace->glyph->lsb_delta); 1128 } 1129 } 1130 } 1131 1132 1133#ifdef ENABLE_GLYPH_SPEW 1134 SkDEBUGF(("FT_Set_Char_Size(this:%p sx:%x sy:%x ", this, fScaleX, fScaleY)); 1135 SkDEBUGF(("Metrics(glyph:%d flags:0x%x) w:%d\n", glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags, glyph->fWidth)); 1136#endif 1137} 1138 1139 1140void SkScalerContext_FreeType::generateImage(const SkGlyph& glyph) { 1141 SkAutoMutexAcquire ac(gFTMutex); 1142 1143 FT_Error err; 1144 1145 if (this->setupSize()) { 1146 goto ERROR; 1147 } 1148 1149 err = FT_Load_Glyph( fFace, glyph.getGlyphID(fBaseGlyphCount), fLoadGlyphFlags); 1150 if (err != 0) { 1151 SkDEBUGF(("SkScalerContext_FreeType::generateImage: FT_Load_Glyph(glyph:%d width:%d height:%d rb:%d flags:%d) returned 0x%x\n", 1152 glyph.getGlyphID(fBaseGlyphCount), glyph.fWidth, glyph.fHeight, glyph.rowBytes(), fLoadGlyphFlags, err)); 1153 ERROR: 1154 memset(glyph.fImage, 0, glyph.rowBytes() * glyph.fHeight); 1155 return; 1156 } 1157 1158 generateGlyphImage(fFace, glyph); 1159} 1160 1161 1162void SkScalerContext_FreeType::generatePath(const SkGlyph& glyph, 1163 SkPath* path) { 1164 SkAutoMutexAcquire ac(gFTMutex); 1165 1166 SkASSERT(&glyph && path); 1167 1168 if (this->setupSize()) { 1169 path->reset(); 1170 return; 1171 } 1172 1173 uint32_t flags = fLoadGlyphFlags; 1174 flags |= FT_LOAD_NO_BITMAP; // ignore embedded bitmaps so we're sure to get the outline 1175 flags &= ~FT_LOAD_RENDER; // don't scan convert (we just want the outline) 1176 1177 FT_Error err = FT_Load_Glyph( fFace, glyph.getGlyphID(fBaseGlyphCount), flags); 1178 1179 if (err != 0) { 1180 SkDEBUGF(("SkScalerContext_FreeType::generatePath: FT_Load_Glyph(glyph:%d flags:%d) returned 0x%x\n", 1181 glyph.getGlyphID(fBaseGlyphCount), flags, err)); 1182 path->reset(); 1183 return; 1184 } 1185 1186 generateGlyphPath(fFace, glyph, path); 1187 1188 // The path's origin from FreeType is always the horizontal layout origin. 1189 // Offset the path so that it is relative to the vertical origin if needed. 1190 if (fRec.fFlags & SkScalerContext::kVertical_Flag) { 1191 FT_Vector vector; 1192 vector.x = fFace->glyph->metrics.vertBearingX - fFace->glyph->metrics.horiBearingX; 1193 vector.y = -fFace->glyph->metrics.vertBearingY - fFace->glyph->metrics.horiBearingY; 1194 FT_Vector_Transform(&vector, &fMatrix22); 1195 path->offset(SkFDot6ToScalar(vector.x), -SkFDot6ToScalar(vector.y)); 1196 } 1197} 1198 1199void SkScalerContext_FreeType::generateFontMetrics(SkPaint::FontMetrics* mx, 1200 SkPaint::FontMetrics* my) { 1201 if (NULL == mx && NULL == my) { 1202 return; 1203 } 1204 1205 SkAutoMutexAcquire ac(gFTMutex); 1206 1207 if (this->setupSize()) { 1208 ERROR: 1209 if (mx) { 1210 sk_bzero(mx, sizeof(SkPaint::FontMetrics)); 1211 } 1212 if (my) { 1213 sk_bzero(my, sizeof(SkPaint::FontMetrics)); 1214 } 1215 return; 1216 } 1217 1218 FT_Face face = fFace; 1219 int upem = face->units_per_EM; 1220 if (upem <= 0) { 1221 goto ERROR; 1222 } 1223 1224 SkPoint pts[6]; 1225 SkFixed ys[6]; 1226 SkFixed scaleY = fScaleY; 1227 SkFixed mxy = fMatrix22.xy; 1228 SkFixed myy = fMatrix22.yy; 1229 SkScalar xmin = SkIntToScalar(face->bbox.xMin) / upem; 1230 SkScalar xmax = SkIntToScalar(face->bbox.xMax) / upem; 1231 1232 int leading = face->height - (face->ascender + -face->descender); 1233 if (leading < 0) { 1234 leading = 0; 1235 } 1236 1237 // Try to get the OS/2 table from the font. This contains the specific 1238 // average font width metrics which Windows uses. 1239 TT_OS2* os2 = (TT_OS2*) FT_Get_Sfnt_Table(face, ft_sfnt_os2); 1240 1241 ys[0] = -face->bbox.yMax; 1242 ys[1] = -face->ascender; 1243 ys[2] = -face->descender; 1244 ys[3] = -face->bbox.yMin; 1245 ys[4] = leading; 1246 ys[5] = os2 ? os2->xAvgCharWidth : 0; 1247 1248 SkScalar x_height; 1249 if (os2 && os2->sxHeight) { 1250 x_height = SkFixedToScalar(SkMulDiv(fScaleX, os2->sxHeight, upem)); 1251 } else { 1252 const FT_UInt x_glyph = FT_Get_Char_Index(fFace, 'x'); 1253 if (x_glyph) { 1254 FT_BBox bbox; 1255 FT_Load_Glyph(fFace, x_glyph, fLoadGlyphFlags); 1256 if (fRec.fFlags & kEmbolden_Flag) { 1257 emboldenOutline(fFace, &fFace->glyph->outline); 1258 } 1259 FT_Outline_Get_CBox(&fFace->glyph->outline, &bbox); 1260 x_height = SkFixedToScalar(SkFDot6ToFixed(bbox.yMax)); 1261 } else { 1262 x_height = 0; 1263 } 1264 } 1265 1266 // convert upem-y values into scalar points 1267 for (int i = 0; i < 6; i++) { 1268 SkFixed y = SkMulDiv(scaleY, ys[i], upem); 1269 SkFixed x = SkFixedMul(mxy, y); 1270 y = SkFixedMul(myy, y); 1271 pts[i].set(SkFixedToScalar(x), SkFixedToScalar(y)); 1272 } 1273 1274 if (mx) { 1275 mx->fTop = pts[0].fX; 1276 mx->fAscent = pts[1].fX; 1277 mx->fDescent = pts[2].fX; 1278 mx->fBottom = pts[3].fX; 1279 mx->fLeading = pts[4].fX; 1280 mx->fAvgCharWidth = pts[5].fX; 1281 mx->fXMin = xmin; 1282 mx->fXMax = xmax; 1283 mx->fXHeight = x_height; 1284 } 1285 if (my) { 1286 my->fTop = pts[0].fY; 1287 my->fAscent = pts[1].fY; 1288 my->fDescent = pts[2].fY; 1289 my->fBottom = pts[3].fY; 1290 my->fLeading = pts[4].fY; 1291 my->fAvgCharWidth = pts[5].fY; 1292 my->fXMin = xmin; 1293 my->fXMax = xmax; 1294 my->fXHeight = x_height; 1295 } 1296} 1297 1298//////////////////////////////////////////////////////////////////////// 1299//////////////////////////////////////////////////////////////////////// 1300 1301SkScalerContext* SkFontHost::CreateScalerContext(const SkDescriptor* desc) { 1302 SkScalerContext_FreeType* c = SkNEW_ARGS(SkScalerContext_FreeType, (desc)); 1303 if (!c->success()) { 1304 SkDELETE(c); 1305 c = NULL; 1306 } 1307 return c; 1308} 1309 1310/////////////////////////////////////////////////////////////////////////////// 1311 1312/* Export this so that other parts of our FonttHost port can make use of our 1313 ability to extract the name+style from a stream, using FreeType's api. 1314*/ 1315bool find_name_and_attributes(SkStream* stream, SkString* name, 1316 SkTypeface::Style* style, bool* isFixedWidth) { 1317 FT_Library library; 1318 if (FT_Init_FreeType(&library)) { 1319 return false; 1320 } 1321 1322 FT_Open_Args args; 1323 memset(&args, 0, sizeof(args)); 1324 1325 const void* memoryBase = stream->getMemoryBase(); 1326 FT_StreamRec streamRec; 1327 1328 if (NULL != memoryBase) { 1329 args.flags = FT_OPEN_MEMORY; 1330 args.memory_base = (const FT_Byte*)memoryBase; 1331 args.memory_size = stream->getLength(); 1332 } else { 1333 memset(&streamRec, 0, sizeof(streamRec)); 1334 streamRec.size = stream->read(NULL, 0); 1335 streamRec.descriptor.pointer = stream; 1336 streamRec.read = sk_stream_read; 1337 streamRec.close = sk_stream_close; 1338 1339 args.flags = FT_OPEN_STREAM; 1340 args.stream = &streamRec; 1341 } 1342 1343 FT_Face face; 1344 if (FT_Open_Face(library, &args, 0, &face)) { 1345 FT_Done_FreeType(library); 1346 return false; 1347 } 1348 1349 int tempStyle = SkTypeface::kNormal; 1350 if (face->style_flags & FT_STYLE_FLAG_BOLD) { 1351 tempStyle |= SkTypeface::kBold; 1352 } 1353 if (face->style_flags & FT_STYLE_FLAG_ITALIC) { 1354 tempStyle |= SkTypeface::kItalic; 1355 } 1356 1357 if (name) { 1358 name->set(face->family_name); 1359 } 1360 if (style) { 1361 *style = (SkTypeface::Style) tempStyle; 1362 } 1363 if (isFixedWidth) { 1364 *isFixedWidth = FT_IS_FIXED_WIDTH(face); 1365 } 1366 1367 FT_Done_Face(face); 1368 FT_Done_FreeType(library); 1369 return true; 1370} 1371 1372