| /* libs/graphics/ports/SkFontHost_FreeType.cpp |
| ** |
| ** Copyright 2006, The Android Open Source Project |
| ** |
| ** Licensed under the Apache License, Version 2.0 (the "License"); |
| ** you may not use this file except in compliance with the License. |
| ** You may obtain a copy of the License at |
| ** |
| ** http://www.apache.org/licenses/LICENSE-2.0 |
| ** |
| ** Unless required by applicable law or agreed to in writing, software |
| ** distributed under the License is distributed on an "AS IS" BASIS, |
| ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| ** See the License for the specific language governing permissions and |
| ** limitations under the License. |
| */ |
| |
| #include "SkColorPriv.h" |
| #include "SkScalerContext.h" |
| #include "SkBitmap.h" |
| #include "SkCanvas.h" |
| #include "SkDescriptor.h" |
| #include "SkFDot6.h" |
| #include "SkFontHost.h" |
| #include "SkMask.h" |
| #include "SkStream.h" |
| #include "SkString.h" |
| #include "SkThread.h" |
| #include "SkTemplates.h" |
| |
| #include <ft2build.h> |
| #include FT_FREETYPE_H |
| #include FT_OUTLINE_H |
| #include FT_SIZES_H |
| #include FT_TRUETYPE_TABLES_H |
| |
| #if defined(SK_SUPPORT_LCDTEXT) |
| #include FT_LCD_FILTER_H |
| #endif |
| |
| #ifdef FT_ADVANCES_H |
| #include FT_ADVANCES_H |
| #endif |
| |
| #if 0 |
| // Also include the files by name for build tools which require this. |
| #include <freetype/freetype.h> |
| #include <freetype/ftoutln.h> |
| #include <freetype/ftsizes.h> |
| #include <freetype/tttables.h> |
| #include <freetype/ftadvanc.h> |
| #include <freetype/ftlcdfil.h> |
| #endif |
| |
| //#define ENABLE_GLYPH_SPEW // for tracing calls |
| //#define DUMP_STRIKE_CREATION |
| |
| #ifdef SK_DEBUG |
| #define SkASSERT_CONTINUE(pred) \ |
| do { \ |
| if (!(pred)) \ |
| SkDebugf("file %s:%d: assert failed '" #pred "'\n", __FILE__, __LINE__); \ |
| } while (false) |
| #else |
| #define SkASSERT_CONTINUE(pred) |
| #endif |
| |
| ////////////////////////////////////////////////////////////////////////// |
| |
| struct SkFaceRec; |
| |
| static SkMutex gFTMutex; |
| static int gFTCount; |
| static FT_Library gFTLibrary; |
| static SkFaceRec* gFaceRecHead; |
| static bool gLCDSupportValid; // true iff |gLCDSupport| has been set. |
| static bool gLCDSupport; // true iff LCD is supported by the runtime. |
| |
| ///////////////////////////////////////////////////////////////////////// |
| |
| static bool |
| InitFreetype() { |
| FT_Error err = FT_Init_FreeType(&gFTLibrary); |
| if (err) |
| return false; |
| |
| #if defined(SK_SUPPORT_LCDTEXT) |
| // Setup LCD filtering. This reduces colour fringes for LCD rendered |
| // glyphs. |
| err = FT_Library_SetLcdFilter(gFTLibrary, FT_LCD_FILTER_DEFAULT); |
| gLCDSupport = err == 0; |
| #endif |
| gLCDSupportValid = true; |
| |
| return true; |
| } |
| |
| class SkScalerContext_FreeType : public SkScalerContext { |
| public: |
| SkScalerContext_FreeType(const SkDescriptor* desc); |
| virtual ~SkScalerContext_FreeType(); |
| |
| bool success() const { |
| return fFaceRec != NULL && |
| fFTSize != NULL && |
| fFace != NULL; |
| } |
| |
| protected: |
| virtual unsigned generateGlyphCount() const; |
| virtual uint16_t generateCharToGlyph(SkUnichar uni); |
| virtual void generateAdvance(SkGlyph* glyph); |
| virtual void generateMetrics(SkGlyph* glyph); |
| virtual void generateImage(const SkGlyph& glyph); |
| virtual void generatePath(const SkGlyph& glyph, SkPath* path); |
| virtual void generateFontMetrics(SkPaint::FontMetrics* mx, |
| SkPaint::FontMetrics* my); |
| virtual SkUnichar generateGlyphToChar(uint16_t glyph); |
| |
| private: |
| SkFaceRec* fFaceRec; |
| FT_Face fFace; // reference to shared face in gFaceRecHead |
| FT_Size fFTSize; // our own copy |
| SkFixed fScaleX, fScaleY; |
| FT_Matrix fMatrix22; |
| uint32_t fLoadGlyphFlags; |
| |
| FT_Error setupSize(); |
| void emboldenOutline(FT_Outline* outline); |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////////////// |
| |
| #include "SkStream.h" |
| |
| struct SkFaceRec { |
| SkFaceRec* fNext; |
| FT_Face fFace; |
| FT_StreamRec fFTStream; |
| SkStream* fSkStream; |
| uint32_t fRefCnt; |
| uint32_t fFontID; |
| |
| // assumes ownership of the stream, will call unref() when its done |
| SkFaceRec(SkStream* strm, uint32_t fontID); |
| ~SkFaceRec() { |
| fSkStream->unref(); |
| } |
| }; |
| |
| extern "C" { |
| static unsigned long sk_stream_read(FT_Stream stream, |
| unsigned long offset, |
| unsigned char* buffer, |
| unsigned long count ) { |
| SkStream* str = (SkStream*)stream->descriptor.pointer; |
| |
| if (count) { |
| if (!str->rewind()) { |
| return 0; |
| } else { |
| unsigned long ret; |
| if (offset) { |
| ret = str->read(NULL, offset); |
| if (ret != offset) { |
| return 0; |
| } |
| } |
| ret = str->read(buffer, count); |
| if (ret != count) { |
| return 0; |
| } |
| count = ret; |
| } |
| } |
| return count; |
| } |
| |
| static void sk_stream_close( FT_Stream stream) {} |
| } |
| |
| SkFaceRec::SkFaceRec(SkStream* strm, uint32_t fontID) |
| : fSkStream(strm), fFontID(fontID) { |
| // SkDEBUGF(("SkFaceRec: opening %s (%p)\n", key.c_str(), strm)); |
| |
| sk_bzero(&fFTStream, sizeof(fFTStream)); |
| fFTStream.size = fSkStream->getLength(); |
| fFTStream.descriptor.pointer = fSkStream; |
| fFTStream.read = sk_stream_read; |
| fFTStream.close = sk_stream_close; |
| } |
| |
| // Will return 0 on failure |
| static SkFaceRec* ref_ft_face(uint32_t fontID) { |
| SkFaceRec* rec = gFaceRecHead; |
| while (rec) { |
| if (rec->fFontID == fontID) { |
| SkASSERT(rec->fFace); |
| rec->fRefCnt += 1; |
| return rec; |
| } |
| rec = rec->fNext; |
| } |
| |
| SkStream* strm = SkFontHost::OpenStream(fontID); |
| if (NULL == strm) { |
| SkDEBUGF(("SkFontHost::OpenStream failed opening %x\n", fontID)); |
| return 0; |
| } |
| |
| // this passes ownership of strm to the rec |
| rec = SkNEW_ARGS(SkFaceRec, (strm, fontID)); |
| |
| FT_Open_Args args; |
| memset(&args, 0, sizeof(args)); |
| const void* memoryBase = strm->getMemoryBase(); |
| |
| if (NULL != memoryBase) { |
| //printf("mmap(%s)\n", keyString.c_str()); |
| args.flags = FT_OPEN_MEMORY; |
| args.memory_base = (const FT_Byte*)memoryBase; |
| args.memory_size = strm->getLength(); |
| } else { |
| //printf("fopen(%s)\n", keyString.c_str()); |
| args.flags = FT_OPEN_STREAM; |
| args.stream = &rec->fFTStream; |
| } |
| |
| if (gFTCount == 0) { |
| if (!InitFreetype()) { |
| return 0; |
| } |
| } |
| ++gFTCount; |
| |
| FT_Error err = FT_Open_Face(gFTLibrary, &args, 0, &rec->fFace); |
| |
| if (err) { // bad filename, try the default font |
| fprintf(stderr, "ERROR: unable to open font '%x'\n", fontID); |
| SkDELETE(rec); |
| return 0; |
| } else { |
| SkASSERT(rec->fFace); |
| //fprintf(stderr, "Opened font '%s'\n", filename.c_str()); |
| rec->fNext = gFaceRecHead; |
| gFaceRecHead = rec; |
| rec->fRefCnt = 1; |
| return rec; |
| } |
| } |
| |
| static void unref_ft_face(FT_Face face) { |
| SkFaceRec* rec = gFaceRecHead; |
| SkFaceRec* prev = NULL; |
| while (rec) { |
| SkFaceRec* next = rec->fNext; |
| if (rec->fFace == face) { |
| if (--rec->fRefCnt == 0) { |
| if (prev) { |
| prev->fNext = next; |
| } else { |
| gFaceRecHead = next; |
| } |
| FT_Done_Face(face); |
| SkDELETE(rec); |
| |
| if (--gFTCount == 0) { |
| FT_Done_FreeType(gFTLibrary); |
| } |
| } |
| return; |
| } |
| prev = rec; |
| rec = next; |
| } |
| SkASSERT("shouldn't get here, face not in list"); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| |
| void SkFontHost::FilterRec(SkScalerContext::Rec* rec) { |
| if (!gLCDSupportValid) { |
| InitFreetype(); |
| FT_Done_FreeType(gFTLibrary); |
| } |
| |
| if (!gLCDSupport && rec->isLCD()) { |
| // If the runtime Freetype library doesn't support LCD mode, we disable |
| // it here. |
| rec->fMaskFormat = SkMask::kA8_Format; |
| } |
| |
| SkPaint::Hinting h = rec->getHinting(); |
| if (SkPaint::kFull_Hinting == h && !rec->isLCD()) { |
| // collapse full->normal hinting if we're not doing LCD |
| h = SkPaint::kNormal_Hinting; |
| } else if (rec->fSubpixelPositioning && SkPaint::kNo_Hinting != h) { |
| // to do subpixel, we must have at most slight hinting |
| h = SkPaint::kSlight_Hinting; |
| } |
| rec->setHinting(h); |
| } |
| |
| uint32_t SkFontHost::GetUnitsPerEm(SkFontID fontID) { |
| SkAutoMutexAcquire ac(gFTMutex); |
| SkFaceRec *rec = ref_ft_face(fontID); |
| uint16_t unitsPerEm = 0; |
| |
| if (rec != NULL && rec->fFace != NULL) { |
| unitsPerEm = rec->fFace->units_per_EM; |
| unref_ft_face(rec->fFace); |
| } |
| |
| return (uint32_t)unitsPerEm; |
| } |
| |
| SkScalerContext_FreeType::SkScalerContext_FreeType(const SkDescriptor* desc) |
| : SkScalerContext(desc) { |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| if (gFTCount == 0) { |
| if (!InitFreetype()) { |
| sk_throw(); |
| } |
| } |
| ++gFTCount; |
| |
| // load the font file |
| fFTSize = NULL; |
| fFace = NULL; |
| fFaceRec = ref_ft_face(fRec.fFontID); |
| if (NULL == fFaceRec) { |
| return; |
| } |
| fFace = fFaceRec->fFace; |
| |
| // compute our factors from the record |
| |
| SkMatrix m; |
| |
| fRec.getSingleMatrix(&m); |
| |
| #ifdef DUMP_STRIKE_CREATION |
| SkString keyString; |
| SkFontHost::GetDescriptorKeyString(desc, &keyString); |
| printf("========== strike [%g %g %g] [%g %g %g %g] hints %d format %d %s\n", SkScalarToFloat(fRec.fTextSize), |
| SkScalarToFloat(fRec.fPreScaleX), SkScalarToFloat(fRec.fPreSkewX), |
| SkScalarToFloat(fRec.fPost2x2[0][0]), SkScalarToFloat(fRec.fPost2x2[0][1]), |
| SkScalarToFloat(fRec.fPost2x2[1][0]), SkScalarToFloat(fRec.fPost2x2[1][1]), |
| fRec.getHinting(), fRec.fMaskFormat, keyString.c_str()); |
| #endif |
| |
| // now compute our scale factors |
| SkScalar sx = m.getScaleX(); |
| SkScalar sy = m.getScaleY(); |
| |
| if (m.getSkewX() || m.getSkewY() || sx < 0 || sy < 0) { |
| // sort of give up on hinting |
| sx = SkMaxScalar(SkScalarAbs(sx), SkScalarAbs(m.getSkewX())); |
| sy = SkMaxScalar(SkScalarAbs(m.getSkewY()), SkScalarAbs(sy)); |
| sx = sy = SkScalarAve(sx, sy); |
| |
| SkScalar inv = SkScalarInvert(sx); |
| |
| // flip the skew elements to go from our Y-down system to FreeType's |
| fMatrix22.xx = SkScalarToFixed(SkScalarMul(m.getScaleX(), inv)); |
| fMatrix22.xy = -SkScalarToFixed(SkScalarMul(m.getSkewX(), inv)); |
| fMatrix22.yx = -SkScalarToFixed(SkScalarMul(m.getSkewY(), inv)); |
| fMatrix22.yy = SkScalarToFixed(SkScalarMul(m.getScaleY(), inv)); |
| } else { |
| fMatrix22.xx = fMatrix22.yy = SK_Fixed1; |
| fMatrix22.xy = fMatrix22.yx = 0; |
| } |
| |
| fScaleX = SkScalarToFixed(sx); |
| fScaleY = SkScalarToFixed(sy); |
| |
| // compute the flags we send to Load_Glyph |
| { |
| FT_Int32 loadFlags = FT_LOAD_DEFAULT; |
| |
| switch (fRec.getHinting()) { |
| case SkPaint::kNo_Hinting: |
| loadFlags = FT_LOAD_NO_HINTING; |
| break; |
| case SkPaint::kSlight_Hinting: |
| loadFlags = FT_LOAD_TARGET_LIGHT; // This implies FORCE_AUTOHINT |
| break; |
| case SkPaint::kNormal_Hinting: |
| loadFlags = FT_LOAD_TARGET_NORMAL; |
| break; |
| case SkPaint::kFull_Hinting: |
| loadFlags = FT_LOAD_TARGET_NORMAL; |
| if (SkMask::kHorizontalLCD_Format == fRec.fMaskFormat) |
| loadFlags = FT_LOAD_TARGET_LCD; |
| else if (SkMask::kVerticalLCD_Format == fRec.fMaskFormat) |
| loadFlags = FT_LOAD_TARGET_LCD_V; |
| break; |
| default: |
| SkDebugf("---------- UNKNOWN hinting %d\n", fRec.getHinting()); |
| break; |
| } |
| |
| if ((fRec.fFlags & SkScalerContext::kEmbeddedBitmapText_Flag) == 0) |
| loadFlags |= FT_LOAD_NO_BITMAP; |
| |
| fLoadGlyphFlags = loadFlags; |
| } |
| |
| // now create the FT_Size |
| |
| { |
| FT_Error err; |
| |
| err = FT_New_Size(fFace, &fFTSize); |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::FT_New_Size(%x): FT_Set_Char_Size(0x%x, 0x%x) returned 0x%x\n", |
| fFaceRec->fFontID, fScaleX, fScaleY, err)); |
| fFace = NULL; |
| return; |
| } |
| |
| err = FT_Activate_Size(fFTSize); |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::FT_Activate_Size(%x, 0x%x, 0x%x) returned 0x%x\n", |
| fFaceRec->fFontID, fScaleX, fScaleY, err)); |
| fFTSize = NULL; |
| } |
| |
| err = FT_Set_Char_Size( fFace, |
| SkFixedToFDot6(fScaleX), SkFixedToFDot6(fScaleY), |
| 72, 72); |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::FT_Set_Char_Size(%x, 0x%x, 0x%x) returned 0x%x\n", |
| fFaceRec->fFontID, fScaleX, fScaleY, err)); |
| fFace = NULL; |
| return; |
| } |
| |
| FT_Set_Transform( fFace, &fMatrix22, NULL); |
| } |
| } |
| |
| SkScalerContext_FreeType::~SkScalerContext_FreeType() { |
| if (fFTSize != NULL) { |
| FT_Done_Size(fFTSize); |
| } |
| |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| if (fFace != NULL) { |
| unref_ft_face(fFace); |
| } |
| if (--gFTCount == 0) { |
| // SkDEBUGF(("FT_Done_FreeType\n")); |
| FT_Done_FreeType(gFTLibrary); |
| SkDEBUGCODE(gFTLibrary = NULL;) |
| } |
| } |
| |
| /* We call this before each use of the fFace, since we may be sharing |
| this face with other context (at different sizes). |
| */ |
| FT_Error SkScalerContext_FreeType::setupSize() { |
| /* In the off-chance that a font has been removed, we want to error out |
| right away, so call resolve just to be sure. |
| |
| TODO: perhaps we can skip this, by walking the global font cache and |
| killing all of the contexts when we know that a given fontID is going |
| away... |
| */ |
| if (!SkFontHost::ValidFontID(fRec.fFontID)) { |
| return (FT_Error)-1; |
| } |
| |
| FT_Error err = FT_Activate_Size(fFTSize); |
| |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::FT_Activate_Size(%x, 0x%x, 0x%x) returned 0x%x\n", |
| fFaceRec->fFontID, fScaleX, fScaleY, err)); |
| fFTSize = NULL; |
| } else { |
| // seems we need to reset this every time (not sure why, but without it |
| // I get random italics from some other fFTSize) |
| FT_Set_Transform( fFace, &fMatrix22, NULL); |
| } |
| return err; |
| } |
| |
| void SkScalerContext_FreeType::emboldenOutline(FT_Outline* outline) { |
| FT_Pos strength; |
| strength = FT_MulFix(fFace->units_per_EM, fFace->size->metrics.y_scale) |
| / 24; |
| FT_Outline_Embolden(outline, strength); |
| } |
| |
| unsigned SkScalerContext_FreeType::generateGlyphCount() const { |
| return fFace->num_glyphs; |
| } |
| |
| uint16_t SkScalerContext_FreeType::generateCharToGlyph(SkUnichar uni) { |
| return SkToU16(FT_Get_Char_Index( fFace, uni )); |
| } |
| |
| SkUnichar SkScalerContext_FreeType::generateGlyphToChar(uint16_t glyph) { |
| // iterate through each cmap entry, looking for matching glyph indices |
| FT_UInt glyphIndex; |
| SkUnichar charCode = FT_Get_First_Char( fFace, &glyphIndex ); |
| |
| while (glyphIndex != 0) { |
| if (glyphIndex == glyph) { |
| return charCode; |
| } |
| charCode = FT_Get_Next_Char( fFace, charCode, &glyphIndex ); |
| } |
| |
| return 0; |
| } |
| |
| static FT_Pixel_Mode compute_pixel_mode(SkMask::Format format) { |
| switch (format) { |
| case SkMask::kHorizontalLCD_Format: |
| case SkMask::kVerticalLCD_Format: |
| SkASSERT(!"An LCD format should never be passed here"); |
| return FT_PIXEL_MODE_GRAY; |
| case SkMask::kBW_Format: |
| return FT_PIXEL_MODE_MONO; |
| case SkMask::kA8_Format: |
| default: |
| return FT_PIXEL_MODE_GRAY; |
| } |
| } |
| |
| void SkScalerContext_FreeType::generateAdvance(SkGlyph* glyph) { |
| #ifdef FT_ADVANCES_H |
| /* unhinted and light hinted text have linearly scaled advances |
| * which are very cheap to compute with some font formats... |
| */ |
| { |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| if (this->setupSize()) { |
| glyph->zeroMetrics(); |
| return; |
| } |
| |
| FT_Error error; |
| FT_Fixed advance; |
| |
| error = FT_Get_Advance( fFace, glyph->getGlyphID(fBaseGlyphCount), |
| fLoadGlyphFlags | FT_ADVANCE_FLAG_FAST_ONLY, |
| &advance ); |
| if (0 == error) { |
| glyph->fRsbDelta = 0; |
| glyph->fLsbDelta = 0; |
| glyph->fAdvanceX = advance; // advance *2/3; //DEBUG |
| glyph->fAdvanceY = 0; |
| return; |
| } |
| } |
| #endif /* FT_ADVANCES_H */ |
| /* otherwise, we need to load/hint the glyph, which is slower */ |
| this->generateMetrics(glyph); |
| return; |
| } |
| |
| void SkScalerContext_FreeType::generateMetrics(SkGlyph* glyph) { |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| glyph->fRsbDelta = 0; |
| glyph->fLsbDelta = 0; |
| |
| FT_Error err; |
| |
| if (this->setupSize()) { |
| goto ERROR; |
| } |
| |
| err = FT_Load_Glyph( fFace, glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags ); |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::generateMetrics(%x): FT_Load_Glyph(glyph:%d flags:%d) returned 0x%x\n", |
| fFaceRec->fFontID, glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags, err)); |
| ERROR: |
| glyph->zeroMetrics(); |
| return; |
| } |
| |
| switch ( fFace->glyph->format ) { |
| case FT_GLYPH_FORMAT_OUTLINE: |
| FT_BBox bbox; |
| |
| if (fRec.fFlags & kEmbolden_Flag) { |
| emboldenOutline(&fFace->glyph->outline); |
| } |
| FT_Outline_Get_CBox(&fFace->glyph->outline, &bbox); |
| |
| if (fRec.fSubpixelPositioning) { |
| int dx = glyph->getSubXFixed() >> 10; |
| int dy = glyph->getSubYFixed() >> 10; |
| // negate dy since freetype-y-goes-up and skia-y-goes-down |
| bbox.xMin += dx; |
| bbox.yMin -= dy; |
| bbox.xMax += dx; |
| bbox.yMax -= dy; |
| } |
| |
| bbox.xMin &= ~63; |
| bbox.yMin &= ~63; |
| bbox.xMax = (bbox.xMax + 63) & ~63; |
| bbox.yMax = (bbox.yMax + 63) & ~63; |
| |
| glyph->fWidth = SkToU16((bbox.xMax - bbox.xMin) >> 6); |
| glyph->fHeight = SkToU16((bbox.yMax - bbox.yMin) >> 6); |
| glyph->fTop = -SkToS16(bbox.yMax >> 6); |
| glyph->fLeft = SkToS16(bbox.xMin >> 6); |
| break; |
| |
| case FT_GLYPH_FORMAT_BITMAP: |
| glyph->fWidth = SkToU16(fFace->glyph->bitmap.width); |
| glyph->fHeight = SkToU16(fFace->glyph->bitmap.rows); |
| glyph->fTop = -SkToS16(fFace->glyph->bitmap_top); |
| glyph->fLeft = SkToS16(fFace->glyph->bitmap_left); |
| break; |
| |
| default: |
| SkASSERT(!"unknown glyph format"); |
| goto ERROR; |
| } |
| |
| if (!fRec.fSubpixelPositioning) { |
| glyph->fAdvanceX = SkFDot6ToFixed(fFace->glyph->advance.x); |
| glyph->fAdvanceY = -SkFDot6ToFixed(fFace->glyph->advance.y); |
| if (fRec.fFlags & kDevKernText_Flag) { |
| glyph->fRsbDelta = SkToS8(fFace->glyph->rsb_delta); |
| glyph->fLsbDelta = SkToS8(fFace->glyph->lsb_delta); |
| } |
| } else { |
| glyph->fAdvanceX = SkFixedMul(fMatrix22.xx, fFace->glyph->linearHoriAdvance); |
| glyph->fAdvanceY = -SkFixedMul(fMatrix22.yx, fFace->glyph->linearHoriAdvance); |
| } |
| |
| #ifdef ENABLE_GLYPH_SPEW |
| SkDEBUGF(("FT_Set_Char_Size(this:%p sx:%x sy:%x ", this, fScaleX, fScaleY)); |
| SkDEBUGF(("Metrics(glyph:%d flags:0x%x) w:%d\n", glyph->getGlyphID(fBaseGlyphCount), fLoadGlyphFlags, glyph->fWidth)); |
| #endif |
| } |
| |
| #if defined(SK_SUPPORT_LCDTEXT) |
| namespace skia_freetype_support { |
| // extern functions from SkFontHost_FreeType_Subpixel |
| extern void CopyFreetypeBitmapToLCDMask(const SkGlyph& dest, const FT_Bitmap& source); |
| extern void CopyFreetypeBitmapToVerticalLCDMask(const SkGlyph& dest, const FT_Bitmap& source); |
| } |
| |
| using namespace skia_freetype_support; |
| #endif |
| |
| void SkScalerContext_FreeType::generateImage(const SkGlyph& glyph) { |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| FT_Error err; |
| |
| if (this->setupSize()) { |
| goto ERROR; |
| } |
| |
| err = FT_Load_Glyph( fFace, glyph.getGlyphID(fBaseGlyphCount), fLoadGlyphFlags); |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::generateImage: FT_Load_Glyph(glyph:%d width:%d height:%d rb:%d flags:%d) returned 0x%x\n", |
| glyph.getGlyphID(fBaseGlyphCount), glyph.fWidth, glyph.fHeight, glyph.rowBytes(), fLoadGlyphFlags, err)); |
| ERROR: |
| memset(glyph.fImage, 0, glyph.rowBytes() * glyph.fHeight); |
| return; |
| } |
| |
| const bool lcdRenderMode = fRec.fMaskFormat == SkMask::kHorizontalLCD_Format || |
| fRec.fMaskFormat == SkMask::kVerticalLCD_Format; |
| |
| switch ( fFace->glyph->format ) { |
| case FT_GLYPH_FORMAT_OUTLINE: { |
| FT_Outline* outline = &fFace->glyph->outline; |
| FT_BBox bbox; |
| FT_Bitmap target; |
| |
| if (fRec.fFlags & kEmbolden_Flag) { |
| emboldenOutline(outline); |
| } |
| |
| int dx = 0, dy = 0; |
| if (fRec.fSubpixelPositioning) { |
| dx = glyph.getSubXFixed() >> 10; |
| dy = glyph.getSubYFixed() >> 10; |
| // negate dy since freetype-y-goes-up and skia-y-goes-down |
| dy = -dy; |
| } |
| FT_Outline_Get_CBox(outline, &bbox); |
| /* |
| what we really want to do for subpixel is |
| offset(dx, dy) |
| compute_bounds |
| offset(bbox & !63) |
| but that is two calls to offset, so we do the following, which |
| achieves the same thing with only one offset call. |
| */ |
| FT_Outline_Translate(outline, dx - ((bbox.xMin + dx) & ~63), |
| dy - ((bbox.yMin + dy) & ~63)); |
| |
| #if defined(SK_SUPPORT_LCDTEXT) |
| if (lcdRenderMode) { |
| // FT_Outline_Get_Bitmap cannot render LCD glyphs. In this case |
| // we have to call FT_Render_Glyph and memcpy the image out. |
| const bool isVertical = fRec.fMaskFormat == SkMask::kVerticalLCD_Format; |
| FT_Render_Mode mode = isVertical ? FT_RENDER_MODE_LCD_V : FT_RENDER_MODE_LCD; |
| FT_Render_Glyph(fFace->glyph, mode); |
| |
| if (isVertical) |
| CopyFreetypeBitmapToVerticalLCDMask(glyph, fFace->glyph->bitmap); |
| else |
| CopyFreetypeBitmapToLCDMask(glyph, fFace->glyph->bitmap); |
| |
| break; |
| } |
| #endif |
| |
| target.width = glyph.fWidth; |
| target.rows = glyph.fHeight; |
| target.pitch = glyph.rowBytes(); |
| target.buffer = reinterpret_cast<uint8_t*>(glyph.fImage); |
| target.pixel_mode = compute_pixel_mode( |
| (SkMask::Format)fRec.fMaskFormat); |
| target.num_grays = 256; |
| |
| memset(glyph.fImage, 0, glyph.rowBytes() * glyph.fHeight); |
| FT_Outline_Get_Bitmap(gFTLibrary, outline, &target); |
| } break; |
| |
| case FT_GLYPH_FORMAT_BITMAP: { |
| SkASSERT_CONTINUE(glyph.fWidth == fFace->glyph->bitmap.width); |
| SkASSERT_CONTINUE(glyph.fHeight == fFace->glyph->bitmap.rows); |
| SkASSERT_CONTINUE(glyph.fTop == -fFace->glyph->bitmap_top); |
| SkASSERT_CONTINUE(glyph.fLeft == fFace->glyph->bitmap_left); |
| |
| const uint8_t* src = (const uint8_t*)fFace->glyph->bitmap.buffer; |
| uint8_t* dst = (uint8_t*)glyph.fImage; |
| |
| if (fFace->glyph->bitmap.pixel_mode == FT_PIXEL_MODE_GRAY || |
| (fFace->glyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO && |
| glyph.fMaskFormat == SkMask::kBW_Format)) { |
| unsigned srcRowBytes = fFace->glyph->bitmap.pitch; |
| unsigned dstRowBytes = glyph.rowBytes(); |
| unsigned minRowBytes = SkMin32(srcRowBytes, dstRowBytes); |
| unsigned extraRowBytes = dstRowBytes - minRowBytes; |
| |
| for (int y = fFace->glyph->bitmap.rows - 1; y >= 0; --y) { |
| memcpy(dst, src, minRowBytes); |
| memset(dst + minRowBytes, 0, extraRowBytes); |
| src += srcRowBytes; |
| dst += dstRowBytes; |
| } |
| } else if (fFace->glyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO && |
| (glyph.fMaskFormat == SkMask::kA8_Format || |
| glyph.fMaskFormat == SkMask::kHorizontalLCD_Format || |
| glyph.fMaskFormat == SkMask::kVerticalLCD_Format)) { |
| for (int y = 0; y < fFace->glyph->bitmap.rows; ++y) { |
| uint8_t byte = 0; |
| int bits = 0; |
| const uint8_t* src_row = src; |
| uint8_t* dst_row = dst; |
| |
| for (int x = 0; x < fFace->glyph->bitmap.width; ++x) { |
| if (!bits) { |
| byte = *src_row++; |
| bits = 8; |
| } |
| |
| *dst_row++ = byte & 0x80 ? 0xff : 0; |
| bits--; |
| byte <<= 1; |
| } |
| |
| src += fFace->glyph->bitmap.pitch; |
| dst += glyph.rowBytes(); |
| } |
| } else { |
| SkASSERT(!"unknown glyph bitmap transform needed"); |
| } |
| |
| if (lcdRenderMode) |
| glyph.expandA8ToLCD(); |
| |
| } break; |
| |
| default: |
| SkASSERT(!"unknown glyph format"); |
| goto ERROR; |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #define ft2sk(x) SkFixedToScalar((x) << 10) |
| |
| #if FREETYPE_MAJOR >= 2 && FREETYPE_MINOR >= 2 |
| #define CONST_PARAM const |
| #else // older freetype doesn't use const here |
| #define CONST_PARAM |
| #endif |
| |
| static int move_proc(CONST_PARAM FT_Vector* pt, void* ctx) { |
| SkPath* path = (SkPath*)ctx; |
| path->close(); // to close the previous contour (if any) |
| path->moveTo(ft2sk(pt->x), -ft2sk(pt->y)); |
| return 0; |
| } |
| |
| static int line_proc(CONST_PARAM FT_Vector* pt, void* ctx) { |
| SkPath* path = (SkPath*)ctx; |
| path->lineTo(ft2sk(pt->x), -ft2sk(pt->y)); |
| return 0; |
| } |
| |
| static int quad_proc(CONST_PARAM FT_Vector* pt0, CONST_PARAM FT_Vector* pt1, |
| void* ctx) { |
| SkPath* path = (SkPath*)ctx; |
| path->quadTo(ft2sk(pt0->x), -ft2sk(pt0->y), ft2sk(pt1->x), -ft2sk(pt1->y)); |
| return 0; |
| } |
| |
| static int cubic_proc(CONST_PARAM FT_Vector* pt0, CONST_PARAM FT_Vector* pt1, |
| CONST_PARAM FT_Vector* pt2, void* ctx) { |
| SkPath* path = (SkPath*)ctx; |
| path->cubicTo(ft2sk(pt0->x), -ft2sk(pt0->y), ft2sk(pt1->x), |
| -ft2sk(pt1->y), ft2sk(pt2->x), -ft2sk(pt2->y)); |
| return 0; |
| } |
| |
| void SkScalerContext_FreeType::generatePath(const SkGlyph& glyph, |
| SkPath* path) { |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| SkASSERT(&glyph && path); |
| |
| if (this->setupSize()) { |
| path->reset(); |
| return; |
| } |
| |
| uint32_t flags = fLoadGlyphFlags; |
| flags |= FT_LOAD_NO_BITMAP; // ignore embedded bitmaps so we're sure to get the outline |
| flags &= ~FT_LOAD_RENDER; // don't scan convert (we just want the outline) |
| |
| FT_Error err = FT_Load_Glyph( fFace, glyph.getGlyphID(fBaseGlyphCount), flags); |
| |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::generatePath: FT_Load_Glyph(glyph:%d flags:%d) returned 0x%x\n", |
| glyph.getGlyphID(fBaseGlyphCount), flags, err)); |
| path->reset(); |
| return; |
| } |
| |
| if (fRec.fFlags & kEmbolden_Flag) { |
| emboldenOutline(&fFace->glyph->outline); |
| } |
| |
| FT_Outline_Funcs funcs; |
| |
| funcs.move_to = move_proc; |
| funcs.line_to = line_proc; |
| funcs.conic_to = quad_proc; |
| funcs.cubic_to = cubic_proc; |
| funcs.shift = 0; |
| funcs.delta = 0; |
| |
| err = FT_Outline_Decompose(&fFace->glyph->outline, &funcs, path); |
| |
| if (err != 0) { |
| SkDEBUGF(("SkScalerContext_FreeType::generatePath: FT_Load_Glyph(glyph:%d flags:%d) returned 0x%x\n", |
| glyph.getGlyphID(fBaseGlyphCount), flags, err)); |
| path->reset(); |
| return; |
| } |
| |
| path->close(); |
| } |
| |
| void SkScalerContext_FreeType::generateFontMetrics(SkPaint::FontMetrics* mx, |
| SkPaint::FontMetrics* my) { |
| if (NULL == mx && NULL == my) { |
| return; |
| } |
| |
| SkAutoMutexAcquire ac(gFTMutex); |
| |
| if (this->setupSize()) { |
| ERROR: |
| if (mx) { |
| sk_bzero(mx, sizeof(SkPaint::FontMetrics)); |
| } |
| if (my) { |
| sk_bzero(my, sizeof(SkPaint::FontMetrics)); |
| } |
| return; |
| } |
| |
| FT_Face face = fFace; |
| int upem = face->units_per_EM; |
| if (upem <= 0) { |
| goto ERROR; |
| } |
| |
| SkPoint pts[6]; |
| SkFixed ys[6]; |
| SkFixed scaleY = fScaleY; |
| SkFixed mxy = fMatrix22.xy; |
| SkFixed myy = fMatrix22.yy; |
| SkScalar xmin = SkIntToScalar(face->bbox.xMin) / upem; |
| SkScalar xmax = SkIntToScalar(face->bbox.xMax) / upem; |
| |
| int leading = face->height - (face->ascender + -face->descender); |
| if (leading < 0) { |
| leading = 0; |
| } |
| |
| // Try to get the OS/2 table from the font. This contains the specific |
| // average font width metrics which Windows uses. |
| TT_OS2* os2 = (TT_OS2*) FT_Get_Sfnt_Table(face, ft_sfnt_os2); |
| |
| ys[0] = -face->bbox.yMax; |
| ys[1] = -face->ascender; |
| ys[2] = -face->descender; |
| ys[3] = -face->bbox.yMin; |
| ys[4] = leading; |
| ys[5] = os2 ? os2->xAvgCharWidth : 0; |
| |
| SkScalar x_height; |
| if (os2 && os2->sxHeight) { |
| x_height = SkFixedToScalar(SkMulDiv(fScaleX, os2->sxHeight, upem)); |
| } else { |
| const FT_UInt x_glyph = FT_Get_Char_Index(fFace, 'x'); |
| if (x_glyph) { |
| FT_BBox bbox; |
| FT_Load_Glyph(fFace, x_glyph, fLoadGlyphFlags); |
| if (fRec.fFlags & kEmbolden_Flag) { |
| emboldenOutline(&fFace->glyph->outline); |
| } |
| FT_Outline_Get_CBox(&fFace->glyph->outline, &bbox); |
| x_height = SkIntToScalar(bbox.yMax) / 64; |
| } else { |
| x_height = 0; |
| } |
| } |
| |
| // convert upem-y values into scalar points |
| for (int i = 0; i < 6; i++) { |
| SkFixed y = SkMulDiv(scaleY, ys[i], upem); |
| SkFixed x = SkFixedMul(mxy, y); |
| y = SkFixedMul(myy, y); |
| pts[i].set(SkFixedToScalar(x), SkFixedToScalar(y)); |
| } |
| |
| if (mx) { |
| mx->fTop = pts[0].fX; |
| mx->fAscent = pts[1].fX; |
| mx->fDescent = pts[2].fX; |
| mx->fBottom = pts[3].fX; |
| mx->fLeading = pts[4].fX; |
| mx->fAvgCharWidth = pts[5].fX; |
| mx->fXMin = xmin; |
| mx->fXMax = xmax; |
| mx->fXHeight = x_height; |
| } |
| if (my) { |
| my->fTop = pts[0].fY; |
| my->fAscent = pts[1].fY; |
| my->fDescent = pts[2].fY; |
| my->fBottom = pts[3].fY; |
| my->fLeading = pts[4].fY; |
| my->fAvgCharWidth = pts[5].fY; |
| my->fXMin = xmin; |
| my->fXMax = xmax; |
| my->fXHeight = x_height; |
| } |
| } |
| |
| //////////////////////////////////////////////////////////////////////// |
| //////////////////////////////////////////////////////////////////////// |
| |
| SkScalerContext* SkFontHost::CreateScalerContext(const SkDescriptor* desc) { |
| SkScalerContext_FreeType* c = SkNEW_ARGS(SkScalerContext_FreeType, (desc)); |
| if (!c->success()) { |
| SkDELETE(c); |
| c = NULL; |
| } |
| return c; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| /* Export this so that other parts of our FonttHost port can make use of our |
| ability to extract the name+style from a stream, using FreeType's api. |
| */ |
| bool find_name_and_style(SkStream* stream, SkString* name, SkTypeface::Style* style) { |
| FT_Library library; |
| if (FT_Init_FreeType(&library)) { |
| name->set(NULL); |
| return false; |
| } |
| |
| FT_Open_Args args; |
| memset(&args, 0, sizeof(args)); |
| |
| const void* memoryBase = stream->getMemoryBase(); |
| FT_StreamRec streamRec; |
| |
| if (NULL != memoryBase) { |
| args.flags = FT_OPEN_MEMORY; |
| args.memory_base = (const FT_Byte*)memoryBase; |
| args.memory_size = stream->getLength(); |
| } else { |
| memset(&streamRec, 0, sizeof(streamRec)); |
| streamRec.size = stream->read(NULL, 0); |
| streamRec.descriptor.pointer = stream; |
| streamRec.read = sk_stream_read; |
| streamRec.close = sk_stream_close; |
| |
| args.flags = FT_OPEN_STREAM; |
| args.stream = &streamRec; |
| } |
| |
| FT_Face face; |
| if (FT_Open_Face(library, &args, 0, &face)) { |
| FT_Done_FreeType(library); |
| name->set(NULL); |
| return false; |
| } |
| |
| name->set(face->family_name); |
| int tempStyle = SkTypeface::kNormal; |
| |
| if (face->style_flags & FT_STYLE_FLAG_BOLD) { |
| tempStyle |= SkTypeface::kBold; |
| } |
| if (face->style_flags & FT_STYLE_FLAG_ITALIC) { |
| tempStyle |= SkTypeface::kItalic; |
| } |
| |
| *style = (SkTypeface::Style)tempStyle; |
| FT_Done_Face(face); |
| FT_Done_FreeType(library); |
| return true; |
| } |
