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Edit File: freetype.h

/***************************************************************************/ /* */ /* freetype.h */ /* */ /* FreeType high-level API and common types (specification only). */ /* */ /* Copyright 1996-2017 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ /* modified, and distributed under the terms of the FreeType project */ /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ /* this file you indicate that you have read the license and */ /* understand and accept it fully. */ /* */ /***************************************************************************/ #ifndef FREETYPE_H_ #define FREETYPE_H_ #ifndef FT_FREETYPE_H #error "`ft2build.h' hasn't been included yet!" #error "Please always use macros to include FreeType header files." #error "Example:" #error " #include <ft2build.h>" #error " #include FT_FREETYPE_H" #endif #include <ft2build.h> #include FT_CONFIG_CONFIG_H #include FT_TYPES_H #include FT_ERRORS_H FT_BEGIN_HEADER /*************************************************************************/ /* */ /* <Section> */ /* header_inclusion */ /* */ /* <Title> */ /* FreeType's header inclusion scheme */ /* */ /* <Abstract> */ /* How client applications should include FreeType header files. */ /* */ /* <Description> */ /* To be as flexible as possible (and for historical reasons), */ /* FreeType uses a very special inclusion scheme to load header */ /* files, for example */ /* */ /* { */ /* #include <ft2build.h> */ /* */ /* #include FT_FREETYPE_H */ /* #include FT_OUTLINE_H */ /* } */ /* */ /* A compiler and its preprocessor only needs an include path to find */ /* the file `ft2build.h'; the exact locations and names of the other */ /* FreeType header files are hidden by preprocessor macro names, */ /* loaded by `ft2build.h'. The API documentation always gives the */ /* header macro name needed for a particular function. */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Section> */ /* user_allocation */ /* */ /* <Title> */ /* User allocation */ /* */ /* <Abstract> */ /* How client applications should allocate FreeType data structures. */ /* */ /* <Description> */ /* FreeType assumes that structures allocated by the user and passed */ /* as arguments are zeroed out except for the actual data. In other */ /* words, it is recommended to use `calloc' (or variants of it) */ /* instead of `malloc' for allocation. */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* B A S I C T Y P E S */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Section> */ /* base_interface */ /* */ /* <Title> */ /* Base Interface */ /* */ /* <Abstract> */ /* The FreeType~2 base font interface. */ /* */ /* <Description> */ /* This section describes the most important public high-level API */ /* functions of FreeType~2. */ /* */ /* <Order> */ /* FT_Library */ /* FT_Face */ /* FT_Size */ /* FT_GlyphSlot */ /* FT_CharMap */ /* FT_Encoding */ /* FT_ENC_TAG */ /* */ /* FT_FaceRec */ /* */ /* FT_FACE_FLAG_SCALABLE */ /* FT_FACE_FLAG_FIXED_SIZES */ /* FT_FACE_FLAG_FIXED_WIDTH */ /* FT_FACE_FLAG_HORIZONTAL */ /* FT_FACE_FLAG_VERTICAL */ /* FT_FACE_FLAG_COLOR */ /* FT_FACE_FLAG_SFNT */ /* FT_FACE_FLAG_CID_KEYED */ /* FT_FACE_FLAG_TRICKY */ /* FT_FACE_FLAG_KERNING */ /* FT_FACE_FLAG_MULTIPLE_MASTERS */ /* FT_FACE_FLAG_GLYPH_NAMES */ /* FT_FACE_FLAG_EXTERNAL_STREAM */ /* FT_FACE_FLAG_HINTER */ /* */ /* FT_HAS_HORIZONTAL */ /* FT_HAS_VERTICAL */ /* FT_HAS_KERNING */ /* FT_HAS_FIXED_SIZES */ /* FT_HAS_GLYPH_NAMES */ /* FT_HAS_MULTIPLE_MASTERS */ /* FT_HAS_COLOR */ /* */ /* FT_IS_SFNT */ /* FT_IS_SCALABLE */ /* FT_IS_FIXED_WIDTH */ /* FT_IS_CID_KEYED */ /* FT_IS_TRICKY */ /* */ /* FT_STYLE_FLAG_BOLD */ /* FT_STYLE_FLAG_ITALIC */ /* */ /* FT_SizeRec */ /* FT_Size_Metrics */ /* */ /* FT_GlyphSlotRec */ /* FT_Glyph_Metrics */ /* FT_SubGlyph */ /* */ /* FT_Bitmap_Size */ /* */ /* FT_Init_FreeType */ /* FT_Done_FreeType */ /* */ /* FT_New_Face */ /* FT_Done_Face */ /* FT_Reference_Face */ /* FT_New_Memory_Face */ /* FT_Face_Properties */ /* FT_Open_Face */ /* FT_Open_Args */ /* FT_Parameter */ /* FT_Attach_File */ /* FT_Attach_Stream */ /* */ /* FT_Set_Char_Size */ /* FT_Set_Pixel_Sizes */ /* FT_Request_Size */ /* FT_Select_Size */ /* FT_Size_Request_Type */ /* FT_Size_RequestRec */ /* FT_Size_Request */ /* FT_Set_Transform */ /* FT_Load_Glyph */ /* FT_Get_Char_Index */ /* FT_Get_First_Char */ /* FT_Get_Next_Char */ /* FT_Get_Name_Index */ /* FT_Load_Char */ /* */ /* FT_OPEN_MEMORY */ /* FT_OPEN_STREAM */ /* FT_OPEN_PATHNAME */ /* FT_OPEN_DRIVER */ /* FT_OPEN_PARAMS */ /* */ /* FT_LOAD_DEFAULT */ /* FT_LOAD_RENDER */ /* FT_LOAD_MONOCHROME */ /* FT_LOAD_LINEAR_DESIGN */ /* FT_LOAD_NO_SCALE */ /* FT_LOAD_NO_HINTING */ /* FT_LOAD_NO_BITMAP */ /* FT_LOAD_NO_AUTOHINT */ /* FT_LOAD_COLOR */ /* */ /* FT_LOAD_VERTICAL_LAYOUT */ /* FT_LOAD_IGNORE_TRANSFORM */ /* FT_LOAD_FORCE_AUTOHINT */ /* FT_LOAD_NO_RECURSE */ /* FT_LOAD_PEDANTIC */ /* */ /* FT_LOAD_TARGET_NORMAL */ /* FT_LOAD_TARGET_LIGHT */ /* FT_LOAD_TARGET_MONO */ /* FT_LOAD_TARGET_LCD */ /* FT_LOAD_TARGET_LCD_V */ /* */ /* FT_LOAD_TARGET_MODE */ /* */ /* FT_Render_Glyph */ /* FT_Render_Mode */ /* FT_Get_Kerning */ /* FT_Kerning_Mode */ /* FT_Get_Track_Kerning */ /* FT_Get_Glyph_Name */ /* FT_Get_Postscript_Name */ /* */ /* FT_CharMapRec */ /* FT_Select_Charmap */ /* FT_Set_Charmap */ /* FT_Get_Charmap_Index */ /* */ /* FT_Get_FSType_Flags */ /* FT_Get_SubGlyph_Info */ /* */ /* FT_Face_Internal */ /* FT_Size_Internal */ /* FT_Slot_Internal */ /* */ /* FT_FACE_FLAG_XXX */ /* FT_STYLE_FLAG_XXX */ /* FT_OPEN_XXX */ /* FT_LOAD_XXX */ /* FT_LOAD_TARGET_XXX */ /* FT_SUBGLYPH_FLAG_XXX */ /* FT_FSTYPE_XXX */ /* */ /* FT_HAS_FAST_GLYPHS */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Struct> */ /* FT_Glyph_Metrics */ /* */ /* <Description> */ /* A structure to model the metrics of a single glyph. The values */ /* are expressed in 26.6 fractional pixel format; if the flag */ /* @FT_LOAD_NO_SCALE has been used while loading the glyph, values */ /* are expressed in font units instead. */ /* */ /* <Fields> */ /* width :: */ /* The glyph's width. */ /* */ /* height :: */ /* The glyph's height. */ /* */ /* horiBearingX :: */ /* Left side bearing for horizontal layout. */ /* */ /* horiBearingY :: */ /* Top side bearing for horizontal layout. */ /* */ /* horiAdvance :: */ /* Advance width for horizontal layout. */ /* */ /* vertBearingX :: */ /* Left side bearing for vertical layout. */ /* */ /* vertBearingY :: */ /* Top side bearing for vertical layout. Larger positive values */ /* mean further below the vertical glyph origin. */ /* */ /* vertAdvance :: */ /* Advance height for vertical layout. Positive values mean the */ /* glyph has a positive advance downward. */ /* */ /* <Note> */ /* If not disabled with @FT_LOAD_NO_HINTING, the values represent */ /* dimensions of the hinted glyph (in case hinting is applicable). */ /* */ /* Stroking a glyph with an outside border does not increase */ /* `horiAdvance' or `vertAdvance'; you have to manually adjust these */ /* values to account for the added width and height. */ /* */ /* FreeType doesn't use the `VORG' table data for CFF fonts because */ /* it doesn't have an interface to quickly retrieve the glyph height. */ /* The y~coordinate of the vertical origin can be simply computed as */ /* `vertBearingY + height' after loading a glyph. */ /* */ typedef struct FT_Glyph_Metrics_ { FT_Pos width; FT_Pos height; FT_Pos horiBearingX; FT_Pos horiBearingY; FT_Pos horiAdvance; FT_Pos vertBearingX; FT_Pos vertBearingY; FT_Pos vertAdvance; } FT_Glyph_Metrics; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Bitmap_Size */ /* */ /* <Description> */ /* This structure models the metrics of a bitmap strike (i.e., a set */ /* of glyphs for a given point size and resolution) in a bitmap font. */ /* It is used for the `available_sizes' field of @FT_Face. */ /* */ /* <Fields> */ /* height :: The vertical distance, in pixels, between two */ /* consecutive baselines. It is always positive. */ /* */ /* width :: The average width, in pixels, of all glyphs in the */ /* strike. */ /* */ /* size :: The nominal size of the strike in 26.6 fractional */ /* points. This field is not very useful. */ /* */ /* x_ppem :: The horizontal ppem (nominal width) in 26.6 fractional */ /* pixels. */ /* */ /* y_ppem :: The vertical ppem (nominal height) in 26.6 fractional */ /* pixels. */ /* */ /* <Note> */ /* Windows FNT: */ /* The nominal size given in a FNT font is not reliable. If the */ /* driver finds it incorrect, it sets `size' to some calculated */ /* values, and `x_ppem' and `y_ppem' to the pixel width and height */ /* given in the font, respectively. */ /* */ /* TrueType embedded bitmaps: */ /* `size', `width', and `height' values are not contained in the */ /* bitmap strike itself. They are computed from the global font */ /* parameters. */ /* */ typedef struct FT_Bitmap_Size_ { FT_Short height; FT_Short width; FT_Pos size; FT_Pos x_ppem; FT_Pos y_ppem; } FT_Bitmap_Size; /*************************************************************************/ /*************************************************************************/ /* */ /* O B J E C T C L A S S E S */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FT_Library */ /* */ /* <Description> */ /* A handle to a FreeType library instance. Each `library' is */ /* completely independent from the others; it is the `root' of a set */ /* of objects like fonts, faces, sizes, etc. */ /* */ /* It also embeds a memory manager (see @FT_Memory), as well as a */ /* scan-line converter object (see @FT_Raster). */ /* */ /* In multi-threaded applications it is easiest to use one */ /* `FT_Library' object per thread. In case this is too cumbersome, */ /* a single `FT_Library' object across threads is possible also */ /* (since FreeType version 2.5.6), as long as a mutex lock is used */ /* around @FT_New_Face and @FT_Done_Face. */ /* */ /* <Note> */ /* Library objects are normally created by @FT_Init_FreeType, and */ /* destroyed with @FT_Done_FreeType. If you need reference-counting */ /* (cf. @FT_Reference_Library), use @FT_New_Library and */ /* @FT_Done_Library. */ /* */ typedef struct FT_LibraryRec_ *FT_Library; /*************************************************************************/ /* */ /* <Section> */ /* module_management */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FT_Module */ /* */ /* <Description> */ /* A handle to a given FreeType module object. A module can be a */ /* font driver, a renderer, or anything else that provides services */ /* to the former. */ /* */ typedef struct FT_ModuleRec_* FT_Module; /*************************************************************************/ /* */ /* <Type> */ /* FT_Driver */ /* */ /* <Description> */ /* A handle to a given FreeType font driver object. A font driver */ /* is a module capable of creating faces from font files. */ /* */ typedef struct FT_DriverRec_* FT_Driver; /*************************************************************************/ /* */ /* <Type> */ /* FT_Renderer */ /* */ /* <Description> */ /* A handle to a given FreeType renderer. A renderer is a module in */ /* charge of converting a glyph's outline image to a bitmap. It */ /* supports a single glyph image format, and one or more target */ /* surface depths. */ /* */ typedef struct FT_RendererRec_* FT_Renderer; /*************************************************************************/ /* */ /* <Section> */ /* base_interface */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FT_Face */ /* */ /* <Description> */ /* A handle to a typographic face object. A face object models a */ /* given typeface, in a given style. */ /* */ /* <Note> */ /* A face object also owns a single @FT_GlyphSlot object, as well */ /* as one or more @FT_Size objects. */ /* */ /* Use @FT_New_Face or @FT_Open_Face to create a new face object from */ /* a given filepath or a custom input stream. */ /* */ /* Use @FT_Done_Face to destroy it (along with its slot and sizes). */ /* */ /* An `FT_Face' object can only be safely used from one thread at a */ /* time. Similarly, creation and destruction of `FT_Face' with the */ /* same @FT_Library object can only be done from one thread at a */ /* time. On the other hand, functions like @FT_Load_Glyph and its */ /* siblings are thread-safe and do not need the lock to be held as */ /* long as the same `FT_Face' object is not used from multiple */ /* threads at the same time. */ /* */ /* <Also> */ /* See @FT_FaceRec for the publicly accessible fields of a given face */ /* object. */ /* */ typedef struct FT_FaceRec_* FT_Face; /*************************************************************************/ /* */ /* <Type> */ /* FT_Size */ /* */ /* <Description> */ /* A handle to an object that models a face scaled to a given */ /* character size. */ /* */ /* <Note> */ /* An @FT_Face has one _active_ @FT_Size object that is used by */ /* functions like @FT_Load_Glyph to determine the scaling */ /* transformation that in turn is used to load and hint glyphs and */ /* metrics. */ /* */ /* You can use @FT_Set_Char_Size, @FT_Set_Pixel_Sizes, */ /* @FT_Request_Size or even @FT_Select_Size to change the content */ /* (i.e., the scaling values) of the active @FT_Size. */ /* */ /* You can use @FT_New_Size to create additional size objects for a */ /* given @FT_Face, but they won't be used by other functions until */ /* you activate it through @FT_Activate_Size. Only one size can be */ /* activated at any given time per face. */ /* */ /* <Also> */ /* See @FT_SizeRec for the publicly accessible fields of a given size */ /* object. */ /* */ typedef struct FT_SizeRec_* FT_Size; /*************************************************************************/ /* */ /* <Type> */ /* FT_GlyphSlot */ /* */ /* <Description> */ /* A handle to a given `glyph slot'. A slot is a container that can */ /* hold any of the glyphs contained in its parent face. */ /* */ /* In other words, each time you call @FT_Load_Glyph or */ /* @FT_Load_Char, the slot's content is erased by the new glyph data, */ /* i.e., the glyph's metrics, its image (bitmap or outline), and */ /* other control information. */ /* */ /* <Also> */ /* See @FT_GlyphSlotRec for the publicly accessible glyph fields. */ /* */ typedef struct FT_GlyphSlotRec_* FT_GlyphSlot; /*************************************************************************/ /* */ /* <Type> */ /* FT_CharMap */ /* */ /* <Description> */ /* A handle to a character map (usually abbreviated to `charmap'). A */ /* charmap is used to translate character codes in a given encoding */ /* into glyph indexes for its parent's face. Some font formats may */ /* provide several charmaps per font. */ /* */ /* Each face object owns zero or more charmaps, but only one of them */ /* can be `active', providing the data used by @FT_Get_Char_Index or */ /* @FT_Load_Char. */ /* */ /* The list of available charmaps in a face is available through the */ /* `face->num_charmaps' and `face->charmaps' fields of @FT_FaceRec. */ /* */ /* The currently active charmap is available as `face->charmap'. */ /* You should call @FT_Set_Charmap to change it. */ /* */ /* <Note> */ /* When a new face is created (either through @FT_New_Face or */ /* @FT_Open_Face), the library looks for a Unicode charmap within */ /* the list and automatically activates it. */ /* */ /* <Also> */ /* See @FT_CharMapRec for the publicly accessible fields of a given */ /* character map. */ /* */ typedef struct FT_CharMapRec_* FT_CharMap; /*************************************************************************/ /* */ /* <Macro> */ /* FT_ENC_TAG */ /* */ /* <Description> */ /* This macro converts four-letter tags into an unsigned long. It is */ /* used to define `encoding' identifiers (see @FT_Encoding). */ /* */ /* <Note> */ /* Since many 16-bit compilers don't like 32-bit enumerations, you */ /* should redefine this macro in case of problems to something like */ /* this: */ /* */ /* { */ /* #define FT_ENC_TAG( value, a, b, c, d ) value */ /* } */ /* */ /* to get a simple enumeration without assigning special numbers. */ /* */ #ifndef FT_ENC_TAG #define FT_ENC_TAG( value, a, b, c, d ) \ value = ( ( (FT_UInt32)(a) << 24 ) | \ ( (FT_UInt32)(b) << 16 ) | \ ( (FT_UInt32)(c) << 8 ) | \ (FT_UInt32)(d) ) #endif /* FT_ENC_TAG */ /*************************************************************************/ /* */ /* <Enum> */ /* FT_Encoding */ /* */ /* <Description> */ /* An enumeration to specify character sets supported by charmaps. */ /* Used in the @FT_Select_Charmap API function. */ /* */ /* <Note> */ /* Despite the name, this enumeration lists specific character */ /* repertories (i.e., charsets), and not text encoding methods (e.g., */ /* UTF-8, UTF-16, etc.). */ /* */ /* Other encodings might be defined in the future. */ /* */ /* <Values> */ /* FT_ENCODING_NONE :: */ /* The encoding value~0 is reserved. */ /* */ /* FT_ENCODING_UNICODE :: */ /* The Unicode character set. This value covers all versions of */ /* the Unicode repertoire, including ASCII and Latin-1. Most fonts */ /* include a Unicode charmap, but not all of them. */ /* */ /* For example, if you want to access Unicode value U+1F028 (and */ /* the font contains it), use value 0x1F028 as the input value for */ /* @FT_Get_Char_Index. */ /* */ /* FT_ENCODING_MS_SYMBOL :: */ /* Microsoft Symbol encoding, used to encode mathematical symbols */ /* and wingdings. For more information, see */ /* `http://www.microsoft.com/typography/otspec/recom.htm', */ /* `http://www.kostis.net/charsets/symbol.htm', and */ /* `http://www.kostis.net/charsets/wingding.htm'. */ /* */ /* This encoding uses character codes from the PUA (Private Unicode */ /* Area) in the range U+F020-U+F0FF. */ /* */ /* FT_ENCODING_SJIS :: */ /* Shift JIS encoding for Japanese. More info at */ /* `http://en.wikipedia.org/wiki/Shift_JIS'. See note on */ /* multi-byte encodings below. */ /* */ /* FT_ENCODING_PRC :: */ /* Corresponds to encoding systems mainly for Simplified Chinese as */ /* used in People's Republic of China (PRC). The encoding layout */ /* is based on GB~2312 and its supersets GBK and GB~18030. */ /* */ /* FT_ENCODING_BIG5 :: */ /* Corresponds to an encoding system for Traditional Chinese as */ /* used in Taiwan and Hong Kong. */ /* */ /* FT_ENCODING_WANSUNG :: */ /* Corresponds to the Korean encoding system known as Extended */ /* Wansung (MS Windows code page 949). */ /* For more information see */ /* `http://www.unicode.org/Public/MAPPINGS/VENDORS/MICSFT/WindowsBestFit/bestfit949.txt'. */ /* */ /* FT_ENCODING_JOHAB :: */ /* The Korean standard character set (KS~C 5601-1992), which */ /* corresponds to MS Windows code page 1361. This character set */ /* includes all possible Hangul character combinations. */ /* */ /* FT_ENCODING_ADOBE_LATIN_1 :: */ /* Corresponds to a Latin-1 encoding as defined in a Type~1 */ /* PostScript font. It is limited to 256 character codes. */ /* */ /* FT_ENCODING_ADOBE_STANDARD :: */ /* Adobe Standard encoding, as found in Type~1, CFF, and */ /* OpenType/CFF fonts. It is limited to 256 character codes. */ /* */ /* FT_ENCODING_ADOBE_EXPERT :: */ /* Adobe Expert encoding, as found in Type~1, CFF, and OpenType/CFF */ /* fonts. It is limited to 256 character codes. */ /* */ /* FT_ENCODING_ADOBE_CUSTOM :: */ /* Corresponds to a custom encoding, as found in Type~1, CFF, and */ /* OpenType/CFF fonts. It is limited to 256 character codes. */ /* */ /* FT_ENCODING_APPLE_ROMAN :: */ /* Apple roman encoding. Many TrueType and OpenType fonts contain */ /* a charmap for this 8-bit encoding, since older versions of Mac */ /* OS are able to use it. */ /* */ /* FT_ENCODING_OLD_LATIN_2 :: */ /* This value is deprecated and was neither used nor reported by */ /* FreeType. Don't use or test for it. */ /* */ /* FT_ENCODING_MS_SJIS :: */ /* Same as FT_ENCODING_SJIS. Deprecated. */ /* */ /* FT_ENCODING_MS_GB2312 :: */ /* Same as FT_ENCODING_PRC. Deprecated. */ /* */ /* FT_ENCODING_MS_BIG5 :: */ /* Same as FT_ENCODING_BIG5. Deprecated. */ /* */ /* FT_ENCODING_MS_WANSUNG :: */ /* Same as FT_ENCODING_WANSUNG. Deprecated. */ /* */ /* FT_ENCODING_MS_JOHAB :: */ /* Same as FT_ENCODING_JOHAB. Deprecated. */ /* */ /* <Note> */ /* By default, FreeType automatically synthesizes a Unicode charmap */ /* for PostScript fonts, using their glyph name dictionaries. */ /* However, it also reports the encodings defined explicitly in the */ /* font file, for the cases when they are needed, with the Adobe */ /* values as well. */ /* */ /* FT_ENCODING_NONE is set by the BDF and PCF drivers if the charmap */ /* is neither Unicode nor ISO-8859-1 (otherwise it is set to */ /* FT_ENCODING_UNICODE). Use @FT_Get_BDF_Charset_ID to find out */ /* which encoding is really present. If, for example, the */ /* `cs_registry' field is `KOI8' and the `cs_encoding' field is `R', */ /* the font is encoded in KOI8-R. */ /* */ /* FT_ENCODING_NONE is always set (with a single exception) by the */ /* winfonts driver. Use @FT_Get_WinFNT_Header and examine the */ /* `charset' field of the @FT_WinFNT_HeaderRec structure to find out */ /* which encoding is really present. For example, */ /* @FT_WinFNT_ID_CP1251 (204) means Windows code page 1251 (for */ /* Russian). */ /* */ /* FT_ENCODING_NONE is set if `platform_id' is @TT_PLATFORM_MACINTOSH */ /* and `encoding_id' is not `TT_MAC_ID_ROMAN' (otherwise it is set to */ /* FT_ENCODING_APPLE_ROMAN). */ /* */ /* If `platform_id' is @TT_PLATFORM_MACINTOSH, use the function */ /* @FT_Get_CMap_Language_ID to query the Mac language ID that may */ /* be needed to be able to distinguish Apple encoding variants. See */ /* */ /* http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/Readme.txt */ /* */ /* to get an idea how to do that. Basically, if the language ID */ /* is~0, don't use it, otherwise subtract 1 from the language ID. */ /* Then examine `encoding_id'. If, for example, `encoding_id' is */ /* `TT_MAC_ID_ROMAN' and the language ID (minus~1) is */ /* `TT_MAC_LANGID_GREEK', it is the Greek encoding, not Roman. */ /* `TT_MAC_ID_ARABIC' with `TT_MAC_LANGID_FARSI' means the Farsi */ /* variant the Arabic encoding. */ /* */ typedef enum FT_Encoding_ { FT_ENC_TAG( FT_ENCODING_NONE, 0, 0, 0, 0 ), FT_ENC_TAG( FT_ENCODING_MS_SYMBOL, 's', 'y', 'm', 'b' ), FT_ENC_TAG( FT_ENCODING_UNICODE, 'u', 'n', 'i', 'c' ), FT_ENC_TAG( FT_ENCODING_SJIS, 's', 'j', 'i', 's' ), FT_ENC_TAG( FT_ENCODING_GB2312, 'g', 'b', ' ', ' ' ), FT_ENC_TAG( FT_ENCODING_BIG5, 'b', 'i', 'g', '5' ), FT_ENC_TAG( FT_ENCODING_WANSUNG, 'w', 'a', 'n', 's' ), FT_ENC_TAG( FT_ENCODING_JOHAB, 'j', 'o', 'h', 'a' ), /* for backward compatibility */ FT_ENCODING_MS_SJIS = FT_ENCODING_SJIS, FT_ENCODING_MS_GB2312 = FT_ENCODING_GB2312, FT_ENCODING_MS_BIG5 = FT_ENCODING_BIG5, FT_ENCODING_MS_WANSUNG = FT_ENCODING_WANSUNG, FT_ENCODING_MS_JOHAB = FT_ENCODING_JOHAB, FT_ENC_TAG( FT_ENCODING_ADOBE_STANDARD, 'A', 'D', 'O', 'B' ), FT_ENC_TAG( FT_ENCODING_ADOBE_EXPERT, 'A', 'D', 'B', 'E' ), FT_ENC_TAG( FT_ENCODING_ADOBE_CUSTOM, 'A', 'D', 'B', 'C' ), FT_ENC_TAG( FT_ENCODING_ADOBE_LATIN_1, 'l', 'a', 't', '1' ), FT_ENC_TAG( FT_ENCODING_OLD_LATIN_2, 'l', 'a', 't', '2' ), FT_ENC_TAG( FT_ENCODING_APPLE_ROMAN, 'a', 'r', 'm', 'n' ) } FT_Encoding; /* these constants are deprecated; use the corresponding `FT_Encoding' */ /* values instead */ #define ft_encoding_none FT_ENCODING_NONE #define ft_encoding_unicode FT_ENCODING_UNICODE #define ft_encoding_symbol FT_ENCODING_MS_SYMBOL #define ft_encoding_latin_1 FT_ENCODING_ADOBE_LATIN_1 #define ft_encoding_latin_2 FT_ENCODING_OLD_LATIN_2 #define ft_encoding_sjis FT_ENCODING_SJIS #define ft_encoding_gb2312 FT_ENCODING_GB2312 #define ft_encoding_big5 FT_ENCODING_BIG5 #define ft_encoding_wansung FT_ENCODING_WANSUNG #define ft_encoding_johab FT_ENCODING_JOHAB #define ft_encoding_adobe_standard FT_ENCODING_ADOBE_STANDARD #define ft_encoding_adobe_expert FT_ENCODING_ADOBE_EXPERT #define ft_encoding_adobe_custom FT_ENCODING_ADOBE_CUSTOM #define ft_encoding_apple_roman FT_ENCODING_APPLE_ROMAN /*************************************************************************/ /* */ /* <Struct> */ /* FT_CharMapRec */ /* */ /* <Description> */ /* The base charmap structure. */ /* */ /* <Fields> */ /* face :: A handle to the parent face object. */ /* */ /* encoding :: An @FT_Encoding tag identifying the charmap. Use */ /* this with @FT_Select_Charmap. */ /* */ /* platform_id :: An ID number describing the platform for the */ /* following encoding ID. This comes directly from */ /* the TrueType specification and gets emulated for */ /* other formats. */ /* */ /* encoding_id :: A platform specific encoding number. This also */ /* comes from the TrueType specification and gets */ /* emulated similarly. */ /* */ typedef struct FT_CharMapRec_ { FT_Face face; FT_Encoding encoding; FT_UShort platform_id; FT_UShort encoding_id; } FT_CharMapRec; /*************************************************************************/ /*************************************************************************/ /* */ /* B A S E O B J E C T C L A S S E S */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Type> */ /* FT_Face_Internal */ /* */ /* <Description> */ /* An opaque handle to an `FT_Face_InternalRec' structure that models */ /* the private data of a given @FT_Face object. */ /* */ /* This structure might change between releases of FreeType~2 and is */ /* not generally available to client applications. */ /* */ typedef struct FT_Face_InternalRec_* FT_Face_Internal; /*************************************************************************/ /* */ /* <Struct> */ /* FT_FaceRec */ /* */ /* <Description> */ /* FreeType root face class structure. A face object models a */ /* typeface in a font file. */ /* */ /* <Fields> */ /* num_faces :: The number of faces in the font file. Some */ /* font formats can have multiple faces in */ /* a single font file. */ /* */ /* face_index :: This field holds two different values. */ /* Bits 0-15 are the index of the face in the */ /* font file (starting with value~0). They */ /* are set to~0 if there is only one face in */ /* the font file. */ /* */ /* Bits 16-30 are relevant to GX and OpenType */ /* variation fonts only, holding the named */ /* instance index for the current face index */ /* (starting with value~1; value~0 indicates */ /* font access without a named instance). For */ /* non-variation fonts, bits 16-30 are */ /* ignored. If we have the third named */ /* instance of face~4, say, `face_index' is */ /* set to 0x00030004. */ /* */ /* Bit 31 is always zero (this is, */ /* `face_index' is always a positive value). */ /* */ /* face_flags :: A set of bit flags that give important */ /* information about the face; see */ /* @FT_FACE_FLAG_XXX for the details. */ /* */ /* style_flags :: The lower 16~bits contain a set of bit */ /* flags indicating the style of the face; see */ /* @FT_STYLE_FLAG_XXX for the details. Bits */ /* 16-30 hold the number of named instances */ /* available for the current face if we have a */ /* GX or OpenType variation (sub)font. Bit 31 */ /* is always zero (this is, `style_flags' is */ /* always a positive value). Note that a */ /* variation font has always at least one */ /* named instance, namely the default */ /* instance. */ /* */ /* num_glyphs :: The number of glyphs in the face. If the */ /* face is scalable and has sbits (see */ /* `num_fixed_sizes'), it is set to the number */ /* of outline glyphs. */ /* */ /* For CID-keyed fonts (not in an SFNT */ /* wrapper) this value gives the highest CID */ /* used in the font. */ /* */ /* family_name :: The face's family name. This is an ASCII */ /* string, usually in English, that describes */ /* the typeface's family (like `Times New */ /* Roman', `Bodoni', `Garamond', etc). This */ /* is a least common denominator used to list */ /* fonts. Some formats (TrueType & OpenType) */ /* provide localized and Unicode versions of */ /* this string. Applications should use the */ /* format specific interface to access them. */ /* Can be NULL (e.g., in fonts embedded in a */ /* PDF file). */ /* */ /* In case the font doesn't provide a specific */ /* family name entry, FreeType tries to */ /* synthesize one, deriving it from other name */ /* entries. */ /* */ /* style_name :: The face's style name. This is an ASCII */ /* string, usually in English, that describes */ /* the typeface's style (like `Italic', */ /* `Bold', `Condensed', etc). Not all font */ /* formats provide a style name, so this field */ /* is optional, and can be set to NULL. As */ /* for `family_name', some formats provide */ /* localized and Unicode versions of this */ /* string. Applications should use the format */ /* specific interface to access them. */ /* */ /* num_fixed_sizes :: The number of bitmap strikes in the face. */ /* Even if the face is scalable, there might */ /* still be bitmap strikes, which are called */ /* `sbits' in that case. */ /* */ /* available_sizes :: An array of @FT_Bitmap_Size for all bitmap */ /* strikes in the face. It is set to NULL if */ /* there is no bitmap strike. */ /* */ /* Note that FreeType tries to sanitize the */ /* strike data since they are sometimes sloppy */ /* or incorrect, but this can easily fail. */ /* */ /* num_charmaps :: The number of charmaps in the face. */ /* */ /* charmaps :: An array of the charmaps of the face. */ /* */ /* generic :: A field reserved for client uses. See the */ /* @FT_Generic type description. */ /* */ /* bbox :: The font bounding box. Coordinates are */ /* expressed in font units (see */ /* `units_per_EM'). The box is large enough */ /* to contain any glyph from the font. Thus, */ /* `bbox.yMax' can be seen as the `maximum */ /* ascender', and `bbox.yMin' as the `minimum */ /* descender'. Only relevant for scalable */ /* formats. */ /* */ /* Note that the bounding box might be off by */ /* (at least) one pixel for hinted fonts. See */ /* @FT_Size_Metrics for further discussion. */ /* */ /* units_per_EM :: The number of font units per EM square for */ /* this face. This is typically 2048 for */ /* TrueType fonts, and 1000 for Type~1 fonts. */ /* Only relevant for scalable formats. */ /* */ /* ascender :: The typographic ascender of the face, */ /* expressed in font units. For font formats */ /* not having this information, it is set to */ /* `bbox.yMax'. Only relevant for scalable */ /* formats. */ /* */ /* descender :: The typographic descender of the face, */ /* expressed in font units. For font formats */ /* not having this information, it is set to */ /* `bbox.yMin'. Note that this field is */ /* negative for values below the baseline. */ /* Only relevant for scalable formats. */ /* */ /* height :: This value is the vertical distance */ /* between two consecutive baselines, */ /* expressed in font units. It is always */ /* positive. Only relevant for scalable */ /* formats. */ /* */ /* If you want the global glyph height, use */ /* `ascender - descender'. */ /* */ /* max_advance_width :: The maximum advance width, in font units, */ /* for all glyphs in this face. This can be */ /* used to make word wrapping computations */ /* faster. Only relevant for scalable */ /* formats. */ /* */ /* max_advance_height :: The maximum advance height, in font units, */ /* for all glyphs in this face. This is only */ /* relevant for vertical layouts, and is set */ /* to `height' for fonts that do not provide */ /* vertical metrics. Only relevant for */ /* scalable formats. */ /* */ /* underline_position :: The position, in font units, of the */ /* underline line for this face. It is the */ /* center of the underlining stem. Only */ /* relevant for scalable formats. */ /* */ /* underline_thickness :: The thickness, in font units, of the */ /* underline for this face. Only relevant for */ /* scalable formats. */ /* */ /* glyph :: The face's associated glyph slot(s). */ /* */ /* size :: The current active size for this face. */ /* */ /* charmap :: The current active charmap for this face. */ /* */ /* <Note> */ /* Fields may be changed after a call to @FT_Attach_File or */ /* @FT_Attach_Stream. */ /* */ /* For an OpenType variation font, the values of the following fields */ /* can change after a call to @FT_Set_Var_Design_Coordinates (and */ /* friends) if the font contains an `MVAR' table: `ascender', */ /* `descender', `height', `underline_position', and */ /* `underline_thickness'. */ /* */ typedef struct FT_FaceRec_ { FT_Long num_faces; FT_Long face_index; FT_Long face_flags; FT_Long style_flags; FT_Long num_glyphs; FT_String* family_name; FT_String* style_name; FT_Int num_fixed_sizes; FT_Bitmap_Size* available_sizes; FT_Int num_charmaps; FT_CharMap* charmaps; FT_Generic generic; /*# The following member variables (down to `underline_thickness') */ /*# are only relevant to scalable outlines; cf. @FT_Bitmap_Size */ /*# for bitmap fonts. */ FT_BBox bbox; FT_UShort units_per_EM; FT_Short ascender; FT_Short descender; FT_Short height; FT_Short max_advance_width; FT_Short max_advance_height; FT_Short underline_position; FT_Short underline_thickness; FT_GlyphSlot glyph; FT_Size size; FT_CharMap charmap; /*@private begin */ FT_Driver driver; FT_Memory memory; FT_Stream stream; FT_ListRec sizes_list; FT_Generic autohint; /* face-specific auto-hinter data */ void* extensions; /* unused */ FT_Face_Internal internal; /*@private end */ } FT_FaceRec; /*************************************************************************/ /* */ /* <Enum> */ /* FT_FACE_FLAG_XXX */ /* */ /* <Description> */ /* A list of bit flags used in the `face_flags' field of the */ /* @FT_FaceRec structure. They inform client applications of */ /* properties of the corresponding face. */ /* */ /* <Values> */ /* FT_FACE_FLAG_SCALABLE :: */ /* The face contains outline glyphs. Note that a face can contain */ /* bitmap strikes also, i.e., a face can have both this flag and */ /* @FT_FACE_FLAG_FIXED_SIZES set. */ /* */ /* FT_FACE_FLAG_FIXED_SIZES :: */ /* The face contains bitmap strikes. See also the */ /* `num_fixed_sizes' and `available_sizes' fields of @FT_FaceRec. */ /* */ /* FT_FACE_FLAG_FIXED_WIDTH :: */ /* The face contains fixed-width characters (like Courier, Lucida, */ /* MonoType, etc.). */ /* */ /* FT_FACE_FLAG_SFNT :: */ /* The face uses the SFNT storage scheme. For now, this means */ /* TrueType and OpenType. */ /* */ /* FT_FACE_FLAG_HORIZONTAL :: */ /* The face contains horizontal glyph metrics. This should be set */ /* for all common formats. */ /* */ /* FT_FACE_FLAG_VERTICAL :: */ /* The face contains vertical glyph metrics. This is only */ /* available in some formats, not all of them. */ /* */ /* FT_FACE_FLAG_KERNING :: */ /* The face contains kerning information. If set, the kerning */ /* distance can be retrieved using the function @FT_Get_Kerning. */ /* Otherwise the function always return the vector (0,0). Note */ /* that FreeType doesn't handle kerning data from the SFNT `GPOS' */ /* table (as present in many OpenType fonts). */ /* */ /* FT_FACE_FLAG_FAST_GLYPHS :: */ /* THIS FLAG IS DEPRECATED. DO NOT USE OR TEST IT. */ /* */ /* FT_FACE_FLAG_MULTIPLE_MASTERS :: */ /* The face contains multiple masters and is capable of */ /* interpolating between them. Supported formats are Adobe MM, */ /* TrueType GX, and OpenType variation fonts. */ /* */ /* See the multiple-masters specific API for details. */ /* */ /* FT_FACE_FLAG_GLYPH_NAMES :: */ /* The face contains glyph names, which can be retrieved using */ /* @FT_Get_Glyph_Name. Note that some TrueType fonts contain */ /* broken glyph name tables. Use the function */ /* @FT_Has_PS_Glyph_Names when needed. */ /* */ /* FT_FACE_FLAG_EXTERNAL_STREAM :: */ /* Used internally by FreeType to indicate that a face's stream was */ /* provided by the client application and should not be destroyed */ /* when @FT_Done_Face is called. Don't read or test this flag. */ /* */ /* FT_FACE_FLAG_HINTER :: */ /* The font driver has a hinting machine of its own. For example, */ /* with TrueType fonts, it makes sense to use data from the SFNT */ /* `gasp' table only if the native TrueType hinting engine (with */ /* the bytecode interpreter) is available and active. */ /* */ /* FT_FACE_FLAG_CID_KEYED :: */ /* The face is CID-keyed. In that case, the face is not accessed */ /* by glyph indices but by CID values. For subsetted CID-keyed */ /* fonts this has the consequence that not all index values are a */ /* valid argument to @FT_Load_Glyph. Only the CID values for which */ /* corresponding glyphs in the subsetted font exist make */ /* `FT_Load_Glyph' return successfully; in all other cases you get */ /* an `FT_Err_Invalid_Argument' error. */ /* */ /* Note that CID-keyed fonts that are in an SFNT wrapper (this is, */ /* all OpenType/CFF fonts) don't have this flag set since the */ /* glyphs are accessed in the normal way (using contiguous */ /* indices); the `CID-ness' isn't visible to the application. */ /* */ /* FT_FACE_FLAG_TRICKY :: */ /* The face is `tricky', this is, it always needs the font format's */ /* native hinting engine to get a reasonable result. A typical */ /* example is the old Chinese font `mingli.ttf' (but not */ /* `mingliu.ttc') that uses TrueType bytecode instructions to move */ /* and scale all of its subglyphs. */ /* */ /* It is not possible to auto-hint such fonts using */ /* @FT_LOAD_FORCE_AUTOHINT; it will also ignore */ /* @FT_LOAD_NO_HINTING. You have to set both @FT_LOAD_NO_HINTING */ /* and @FT_LOAD_NO_AUTOHINT to really disable hinting; however, you */ /* probably never want this except for demonstration purposes. */ /* */ /* Currently, there are about a dozen TrueType fonts in the list of */ /* tricky fonts; they are hard-coded in file `ttobjs.c'. */ /* */ /* FT_FACE_FLAG_COLOR :: */ /* The face has color glyph tables. To access color glyphs use */ /* @FT_LOAD_COLOR. */ /* */ #define FT_FACE_FLAG_SCALABLE ( 1L << 0 ) #define FT_FACE_FLAG_FIXED_SIZES ( 1L << 1 ) #define FT_FACE_FLAG_FIXED_WIDTH ( 1L << 2 ) #define FT_FACE_FLAG_SFNT ( 1L << 3 ) #define FT_FACE_FLAG_HORIZONTAL ( 1L << 4 ) #define FT_FACE_FLAG_VERTICAL ( 1L << 5 ) #define FT_FACE_FLAG_KERNING ( 1L << 6 ) #define FT_FACE_FLAG_FAST_GLYPHS ( 1L << 7 ) #define FT_FACE_FLAG_MULTIPLE_MASTERS ( 1L << 8 ) #define FT_FACE_FLAG_GLYPH_NAMES ( 1L << 9 ) #define FT_FACE_FLAG_EXTERNAL_STREAM ( 1L << 10 ) #define FT_FACE_FLAG_HINTER ( 1L << 11 ) #define FT_FACE_FLAG_CID_KEYED ( 1L << 12 ) #define FT_FACE_FLAG_TRICKY ( 1L << 13 ) #define FT_FACE_FLAG_COLOR ( 1L << 14 ) /************************************************************************* * * @macro: * FT_HAS_HORIZONTAL( face ) * * @description: * A macro that returns true whenever a face object contains * horizontal metrics (this is true for all font formats though). * * @also: * @FT_HAS_VERTICAL can be used to check for vertical metrics. * */ #define FT_HAS_HORIZONTAL( face ) \ ( (face)->face_flags & FT_FACE_FLAG_HORIZONTAL ) /************************************************************************* * * @macro: * FT_HAS_VERTICAL( face ) * * @description: * A macro that returns true whenever a face object contains real * vertical metrics (and not only synthesized ones). * */ #define FT_HAS_VERTICAL( face ) \ ( (face)->face_flags & FT_FACE_FLAG_VERTICAL ) /************************************************************************* * * @macro: * FT_HAS_KERNING( face ) * * @description: * A macro that returns true whenever a face object contains kerning * data that can be accessed with @FT_Get_Kerning. * */ #define FT_HAS_KERNING( face ) \ ( (face)->face_flags & FT_FACE_FLAG_KERNING ) /************************************************************************* * * @macro: * FT_IS_SCALABLE( face ) * * @description: * A macro that returns true whenever a face object contains a scalable * font face (true for TrueType, Type~1, Type~42, CID, OpenType/CFF, * and PFR font formats). * */ #define FT_IS_SCALABLE( face ) \ ( (face)->face_flags & FT_FACE_FLAG_SCALABLE ) /************************************************************************* * * @macro: * FT_IS_SFNT( face ) * * @description: * A macro that returns true whenever a face object contains a font * whose format is based on the SFNT storage scheme. This usually * means: TrueType fonts, OpenType fonts, as well as SFNT-based embedded * bitmap fonts. * * If this macro is true, all functions defined in @FT_SFNT_NAMES_H and * @FT_TRUETYPE_TABLES_H are available. * */ #define FT_IS_SFNT( face ) \ ( (face)->face_flags & FT_FACE_FLAG_SFNT ) /************************************************************************* * * @macro: * FT_IS_FIXED_WIDTH( face ) * * @description: * A macro that returns true whenever a face object contains a font face * that contains fixed-width (or `monospace', `fixed-pitch', etc.) * glyphs. * */ #define FT_IS_FIXED_WIDTH( face ) \ ( (face)->face_flags & FT_FACE_FLAG_FIXED_WIDTH ) /************************************************************************* * * @macro: * FT_HAS_FIXED_SIZES( face ) * * @description: * A macro that returns true whenever a face object contains some * embedded bitmaps. See the `available_sizes' field of the * @FT_FaceRec structure. * */ #define FT_HAS_FIXED_SIZES( face ) \ ( (face)->face_flags & FT_FACE_FLAG_FIXED_SIZES ) /************************************************************************* * * @macro: * FT_HAS_FAST_GLYPHS( face ) * * @description: * Deprecated. * */ #define FT_HAS_FAST_GLYPHS( face ) 0 /************************************************************************* * * @macro: * FT_HAS_GLYPH_NAMES( face ) * * @description: * A macro that returns true whenever a face object contains some glyph * names that can be accessed through @FT_Get_Glyph_Name. * */ #define FT_HAS_GLYPH_NAMES( face ) \ ( (face)->face_flags & FT_FACE_FLAG_GLYPH_NAMES ) /************************************************************************* * * @macro: * FT_HAS_MULTIPLE_MASTERS( face ) * * @description: * A macro that returns true whenever a face object contains some * multiple masters. The functions provided by @FT_MULTIPLE_MASTERS_H * are then available to choose the exact design you want. * */ #define FT_HAS_MULTIPLE_MASTERS( face ) \ ( (face)->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS ) /************************************************************************* * * @macro: * FT_IS_NAMED_INSTANCE( face ) * * @description: * A macro that returns true whenever a face object is a named instance * of a GX or OpenType variation font. * */ #define FT_IS_NAMED_INSTANCE( face ) \ ( (face)->face_index & 0x7FFF0000L ) /************************************************************************* * * @macro: * FT_IS_CID_KEYED( face ) * * @description: * A macro that returns true whenever a face object contains a CID-keyed * font. See the discussion of @FT_FACE_FLAG_CID_KEYED for more * details. * * If this macro is true, all functions defined in @FT_CID_H are * available. * */ #define FT_IS_CID_KEYED( face ) \ ( (face)->face_flags & FT_FACE_FLAG_CID_KEYED ) /************************************************************************* * * @macro: * FT_IS_TRICKY( face ) * * @description: * A macro that returns true whenever a face represents a `tricky' font. * See the discussion of @FT_FACE_FLAG_TRICKY for more details. * */ #define FT_IS_TRICKY( face ) \ ( (face)->face_flags & FT_FACE_FLAG_TRICKY ) /************************************************************************* * * @macro: * FT_HAS_COLOR( face ) * * @description: * A macro that returns true whenever a face object contains * tables for color glyphs. * */ #define FT_HAS_COLOR( face ) \ ( (face)->face_flags & FT_FACE_FLAG_COLOR ) /*************************************************************************/ /* */ /* <Const> */ /* FT_STYLE_FLAG_XXX */ /* */ /* <Description> */ /* A list of bit flags to indicate the style of a given face. These */ /* are used in the `style_flags' field of @FT_FaceRec. */ /* */ /* <Values> */ /* FT_STYLE_FLAG_ITALIC :: */ /* The face style is italic or oblique. */ /* */ /* FT_STYLE_FLAG_BOLD :: */ /* The face is bold. */ /* */ /* <Note> */ /* The style information as provided by FreeType is very basic. More */ /* details are beyond the scope and should be done on a higher level */ /* (for example, by analyzing various fields of the `OS/2' table in */ /* SFNT based fonts). */ /* */ #define FT_STYLE_FLAG_ITALIC ( 1 << 0 ) #define FT_STYLE_FLAG_BOLD ( 1 << 1 ) /*************************************************************************/ /* */ /* <Type> */ /* FT_Size_Internal */ /* */ /* <Description> */ /* An opaque handle to an `FT_Size_InternalRec' structure, used to */ /* model private data of a given @FT_Size object. */ /* */ typedef struct FT_Size_InternalRec_* FT_Size_Internal; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Size_Metrics */ /* */ /* <Description> */ /* The size metrics structure gives the metrics of a size object. */ /* */ /* <Fields> */ /* x_ppem :: The width of the scaled EM square in pixels, hence */ /* the term `ppem' (pixels per EM). It is also */ /* referred to as `nominal width'. */ /* */ /* y_ppem :: The height of the scaled EM square in pixels, */ /* hence the term `ppem' (pixels per EM). It is also */ /* referred to as `nominal height'. */ /* */ /* x_scale :: A 16.16 fractional scaling value to convert */ /* horizontal metrics from font units to 26.6 */ /* fractional pixels. Only relevant for scalable */ /* font formats. */ /* */ /* y_scale :: A 16.16 fractional scaling value to convert */ /* vertical metrics from font units to 26.6 */ /* fractional pixels. Only relevant for scalable */ /* font formats. */ /* */ /* ascender :: The ascender in 26.6 fractional pixels, rounded up */ /* to an integer value. See @FT_FaceRec for the */ /* details. */ /* */ /* descender :: The descender in 26.6 fractional pixels, rounded */ /* down to an integer value. See @FT_FaceRec for the */ /* details. */ /* */ /* height :: The height in 26.6 fractional pixels, rounded to */ /* an integer value. See @FT_FaceRec for the */ /* details. */ /* */ /* max_advance :: The maximum advance width in 26.6 fractional */ /* pixels, rounded to an integer value. See */ /* @FT_FaceRec for the details. */ /* */ /* <Note> */ /* The scaling values, if relevant, are determined first during a */ /* size changing operation. The remaining fields are then set by the */ /* driver. For scalable formats, they are usually set to scaled */ /* values of the corresponding fields in @FT_FaceRec. Some values */ /* like ascender or descender are rounded for historical reasons; */ /* more precise values (for outline fonts) can be derived by scaling */ /* the corresponding @FT_FaceRec values manually. */ /* */ /* Note that due to glyph hinting and the selected rendering mode */ /* these values are usually not exact; consequently, they must be */ /* treated as unreliable with an error margin of at least one pixel! */ /* */ /* Indeed, the only way to get the exact metrics is to render _all_ */ /* glyphs. As this would be a definite performance hit, it is up to */ /* client applications to perform such computations. */ /* */ /* The `FT_Size_Metrics' structure is valid for bitmap fonts also. */ /* */ typedef struct FT_Size_Metrics_ { FT_UShort x_ppem; /* horizontal pixels per EM */ FT_UShort y_ppem; /* vertical pixels per EM */ FT_Fixed x_scale; /* scaling values used to convert font */ FT_Fixed y_scale; /* units to 26.6 fractional pixels */ FT_Pos ascender; /* ascender in 26.6 frac. pixels */ FT_Pos descender; /* descender in 26.6 frac. pixels */ FT_Pos height; /* text height in 26.6 frac. pixels */ FT_Pos max_advance; /* max horizontal advance, in 26.6 pixels */ } FT_Size_Metrics; /*************************************************************************/ /* */ /* <Struct> */ /* FT_SizeRec */ /* */ /* <Description> */ /* FreeType root size class structure. A size object models a face */ /* object at a given size. */ /* */ /* <Fields> */ /* face :: Handle to the parent face object. */ /* */ /* generic :: A typeless pointer, unused by the FreeType library or */ /* any of its drivers. It can be used by client */ /* applications to link their own data to each size */ /* object. */ /* */ /* metrics :: Metrics for this size object. This field is read-only. */ /* */ typedef struct FT_SizeRec_ { FT_Face face; /* parent face object */ FT_Generic generic; /* generic pointer for client uses */ FT_Size_Metrics metrics; /* size metrics */ FT_Size_Internal internal; } FT_SizeRec; /*************************************************************************/ /* */ /* <Struct> */ /* FT_SubGlyph */ /* */ /* <Description> */ /* The subglyph structure is an internal object used to describe */ /* subglyphs (for example, in the case of composites). */ /* */ /* <Note> */ /* The subglyph implementation is not part of the high-level API, */ /* hence the forward structure declaration. */ /* */ /* You can however retrieve subglyph information with */ /* @FT_Get_SubGlyph_Info. */ /* */ typedef struct FT_SubGlyphRec_* FT_SubGlyph; /*************************************************************************/ /* */ /* <Type> */ /* FT_Slot_Internal */ /* */ /* <Description> */ /* An opaque handle to an `FT_Slot_InternalRec' structure, used to */ /* model private data of a given @FT_GlyphSlot object. */ /* */ typedef struct FT_Slot_InternalRec_* FT_Slot_Internal; /*************************************************************************/ /* */ /* <Struct> */ /* FT_GlyphSlotRec */ /* */ /* <Description> */ /* FreeType root glyph slot class structure. A glyph slot is a */ /* container where individual glyphs can be loaded, be they in */ /* outline or bitmap format. */ /* */ /* <Fields> */ /* library :: A handle to the FreeType library instance */ /* this slot belongs to. */ /* */ /* face :: A handle to the parent face object. */ /* */ /* next :: In some cases (like some font tools), several */ /* glyph slots per face object can be a good */ /* thing. As this is rare, the glyph slots are */ /* listed through a direct, single-linked list */ /* using its `next' field. */ /* */ /* generic :: A typeless pointer unused by the FreeType */ /* library or any of its drivers. It can be */ /* used by client applications to link their own */ /* data to each glyph slot object. */ /* */ /* metrics :: The metrics of the last loaded glyph in the */ /* slot. The returned values depend on the last */ /* load flags (see the @FT_Load_Glyph API */ /* function) and can be expressed either in 26.6 */ /* fractional pixels or font units. */ /* */ /* Note that even when the glyph image is */ /* transformed, the metrics are not. */ /* */ /* linearHoriAdvance :: The advance width of the unhinted glyph. */ /* Its value is expressed in 16.16 fractional */ /* pixels, unless @FT_LOAD_LINEAR_DESIGN is set */ /* when loading the glyph. This field can be */ /* important to perform correct WYSIWYG layout. */ /* Only relevant for outline glyphs. */ /* */ /* linearVertAdvance :: The advance height of the unhinted glyph. */ /* Its value is expressed in 16.16 fractional */ /* pixels, unless @FT_LOAD_LINEAR_DESIGN is set */ /* when loading the glyph. This field can be */ /* important to perform correct WYSIWYG layout. */ /* Only relevant for outline glyphs. */ /* */ /* advance :: This shorthand is, depending on */ /* @FT_LOAD_IGNORE_TRANSFORM, the transformed */ /* (hinted) advance width for the glyph, in 26.6 */ /* fractional pixel format. As specified with */ /* @FT_LOAD_VERTICAL_LAYOUT, it uses either the */ /* `horiAdvance' or the `vertAdvance' value of */ /* `metrics' field. */ /* */ /* format :: This field indicates the format of the image */ /* contained in the glyph slot. Typically */ /* @FT_GLYPH_FORMAT_BITMAP, */ /* @FT_GLYPH_FORMAT_OUTLINE, or */ /* @FT_GLYPH_FORMAT_COMPOSITE, but other values */ /* are possible. */ /* */ /* bitmap :: This field is used as a bitmap descriptor */ /* when the slot format is */ /* @FT_GLYPH_FORMAT_BITMAP. Note that the */ /* address and content of the bitmap buffer can */ /* change between calls of @FT_Load_Glyph and a */ /* few other functions. */ /* */ /* bitmap_left :: The bitmap's left bearing expressed in */ /* integer pixels. Only valid if the format is */ /* @FT_GLYPH_FORMAT_BITMAP, this is, if the */ /* glyph slot contains a bitmap. */ /* */ /* bitmap_top :: The bitmap's top bearing expressed in integer */ /* pixels. This is the distance from the */ /* baseline to the top-most glyph scanline, */ /* upwards y~coordinates being *positive*. */ /* */ /* outline :: The outline descriptor for the current glyph */ /* image if its format is */ /* @FT_GLYPH_FORMAT_OUTLINE. Once a glyph is */ /* loaded, `outline' can be transformed, */ /* distorted, emboldened, etc. However, it must */ /* not be freed. */ /* */ /* num_subglyphs :: The number of subglyphs in a composite glyph. */ /* This field is only valid for the composite */ /* glyph format that should normally only be */ /* loaded with the @FT_LOAD_NO_RECURSE flag. */ /* */ /* subglyphs :: An array of subglyph descriptors for */ /* composite glyphs. There are `num_subglyphs' */ /* elements in there. Currently internal to */ /* FreeType. */ /* */ /* control_data :: Certain font drivers can also return the */ /* control data for a given glyph image (e.g. */ /* TrueType bytecode, Type~1 charstrings, etc.). */ /* This field is a pointer to such data; it is */ /* currently internal to FreeType. */ /* */ /* control_len :: This is the length in bytes of the control */ /* data. Currently internal to FreeType. */ /* */ /* other :: Reserved. */ /* */ /* lsb_delta :: The difference between hinted and unhinted */ /* left side bearing while auto-hinting is */ /* active. Zero otherwise. */ /* */ /* rsb_delta :: The difference between hinted and unhinted */ /* right side bearing while auto-hinting is */ /* active. Zero otherwise. */ /* */ /* <Note> */ /* If @FT_Load_Glyph is called with default flags (see */ /* @FT_LOAD_DEFAULT) the glyph image is loaded in the glyph slot in */ /* its native format (e.g., an outline glyph for TrueType and Type~1 */ /* formats). */ /* */ /* This image can later be converted into a bitmap by calling */ /* @FT_Render_Glyph. This function searches the current renderer for */ /* the native image's format, then invokes it. */ /* */ /* The renderer is in charge of transforming the native image through */ /* the slot's face transformation fields, then converting it into a */ /* bitmap that is returned in `slot->bitmap'. */ /* */ /* Note that `slot->bitmap_left' and `slot->bitmap_top' are also used */ /* to specify the position of the bitmap relative to the current pen */ /* position (e.g., coordinates (0,0) on the baseline). Of course, */ /* `slot->format' is also changed to @FT_GLYPH_FORMAT_BITMAP. */ /* */ /* Here is a small pseudo code fragment that shows how to use */ /* `lsb_delta' and `rsb_delta' to do fractional positioning of */ /* glyphs: */ /* */ /* { */ /* FT_GlyphSlot slot = face->glyph; */ /* FT_Pos origin_x = 0; */ /* */ /* */ /* for all glyphs do */ /* <load glyph with `FT_Load_Glyph'> */ /* */ /* FT_Outline_Translate( slot->outline, origin_x & 63, 0 ); */ /* */ /* <save glyph image, or render glyph, or ...> */ /* */ /* <compute kern between current and next glyph */ /* and add it to `origin_x'> */ /* */ /* origin_x += slot->advance.x; */ /* origin_x += slot->rsb_delta - slot->lsb_relta; */ /* endfor */ /* } */ /* */ /* Here is another small pseudo code fragment that shows how to use */ /* `lsb_delta' and `rsb_delta' to improve integer positioning of */ /* glyphs: */ /* */ /* { */ /* FT_GlyphSlot slot = face->glyph; */ /* FT_Pos origin_x = 0; */ /* FT_Pos prev_rsb_delta = 0; */ /* */ /* */ /* for all glyphs do */ /* <compute kern between current and previous glyph */ /* and add it to `origin_x'> */ /* */ /* <load glyph with `FT_Load_Glyph'> */ /* */ /* if ( prev_rsb_delta - slot->lsb_delta >= 32 ) */ /* origin_x -= 64; */ /* else if ( prev_rsb_delta - slot->lsb_delta < -32 ) */ /* origin_x += 64; */ /* */ /* prev_rsb_delta = slot->rsb_delta; */ /* */ /* <save glyph image, or render glyph, or ...> */ /* */ /* origin_x += slot->advance.x; */ /* endfor */ /* } */ /* */ /* If you use strong auto-hinting, you *must* apply these delta */ /* values! Otherwise you will experience far too large inter-glyph */ /* spacing at small rendering sizes in most cases. Note that it */ /* doesn't harm to use the above code for other hinting modes also, */ /* since the delta values are zero then. */ /* */ typedef struct FT_GlyphSlotRec_ { FT_Library library; FT_Face face; FT_GlyphSlot next; FT_UInt reserved; /* retained for binary compatibility */ FT_Generic generic; FT_Glyph_Metrics metrics; FT_Fixed linearHoriAdvance; FT_Fixed linearVertAdvance; FT_Vector advance; FT_Glyph_Format format; FT_Bitmap bitmap; FT_Int bitmap_left; FT_Int bitmap_top; FT_Outline outline; FT_UInt num_subglyphs; FT_SubGlyph subglyphs; void* control_data; long control_len; FT_Pos lsb_delta; FT_Pos rsb_delta; void* other; FT_Slot_Internal internal; } FT_GlyphSlotRec; /*************************************************************************/ /*************************************************************************/ /* */ /* F U N C T I O N S */ /* */ /*************************************************************************/ /*************************************************************************/ /*************************************************************************/ /* */ /* <Function> */ /* FT_Init_FreeType */ /* */ /* <Description> */ /* Initialize a new FreeType library object. The set of modules */ /* that are registered by this function is determined at build time. */ /* */ /* <Output> */ /* alibrary :: A handle to a new library object. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* In case you want to provide your own memory allocating routines, */ /* use @FT_New_Library instead, followed by a call to */ /* @FT_Add_Default_Modules (or a series of calls to @FT_Add_Module) */ /* and @FT_Set_Default_Properties. */ /* */ /* See the documentation of @FT_Library and @FT_Face for */ /* multi-threading issues. */ /* */ /* If you need reference-counting (cf. @FT_Reference_Library), use */ /* @FT_New_Library and @FT_Done_Library. */ /* */ /* If compilation option FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES is */ /* set, this function reads the `FREETYPE_PROPERTIES' environment */ /* variable to control driver properties. See sections @auto_hinter, */ /* @cff_driver, @pcf_driver, and @tt_driver for more. */ /* */ FT_EXPORT( FT_Error ) FT_Init_FreeType( FT_Library *alibrary ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Done_FreeType */ /* */ /* <Description> */ /* Destroy a given FreeType library object and all of its children, */ /* including resources, drivers, faces, sizes, etc. */ /* */ /* <Input> */ /* library :: A handle to the target library object. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ FT_EXPORT( FT_Error ) FT_Done_FreeType( FT_Library library ); /*************************************************************************/ /* */ /* <Enum> */ /* FT_OPEN_XXX */ /* */ /* <Description> */ /* A list of bit field constants used within the `flags' field of the */ /* @FT_Open_Args structure. */ /* */ /* <Values> */ /* FT_OPEN_MEMORY :: This is a memory-based stream. */ /* */ /* FT_OPEN_STREAM :: Copy the stream from the `stream' field. */ /* */ /* FT_OPEN_PATHNAME :: Create a new input stream from a C~path */ /* name. */ /* */ /* FT_OPEN_DRIVER :: Use the `driver' field. */ /* */ /* FT_OPEN_PARAMS :: Use the `num_params' and `params' fields. */ /* */ /* <Note> */ /* The `FT_OPEN_MEMORY', `FT_OPEN_STREAM', and `FT_OPEN_PATHNAME' */ /* flags are mutually exclusive. */ /* */ #define FT_OPEN_MEMORY 0x1 #define FT_OPEN_STREAM 0x2 #define FT_OPEN_PATHNAME 0x4 #define FT_OPEN_DRIVER 0x8 #define FT_OPEN_PARAMS 0x10 /* these constants are deprecated; use the corresponding `FT_OPEN_XXX' */ /* values instead */ #define ft_open_memory FT_OPEN_MEMORY #define ft_open_stream FT_OPEN_STREAM #define ft_open_pathname FT_OPEN_PATHNAME #define ft_open_driver FT_OPEN_DRIVER #define ft_open_params FT_OPEN_PARAMS /*************************************************************************/ /* */ /* <Struct> */ /* FT_Parameter */ /* */ /* <Description> */ /* A simple structure to pass more or less generic parameters to */ /* @FT_Open_Face and @FT_Face_Properties. */ /* */ /* <Fields> */ /* tag :: A four-byte identification tag. */ /* */ /* data :: A pointer to the parameter data. */ /* */ /* <Note> */ /* The ID and function of parameters are driver-specific. See the */ /* various FT_PARAM_TAG_XXX flags for more information. */ /* */ typedef struct FT_Parameter_ { FT_ULong tag; FT_Pointer data; } FT_Parameter; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Open_Args */ /* */ /* <Description> */ /* A structure to indicate how to open a new font file or stream. A */ /* pointer to such a structure can be used as a parameter for the */ /* functions @FT_Open_Face and @FT_Attach_Stream. */ /* */ /* <Fields> */ /* flags :: A set of bit flags indicating how to use the */ /* structure. */ /* */ /* memory_base :: The first byte of the file in memory. */ /* */ /* memory_size :: The size in bytes of the file in memory. */ /* */ /* pathname :: A pointer to an 8-bit file pathname. */ /* */ /* stream :: A handle to a source stream object. */ /* */ /* driver :: This field is exclusively used by @FT_Open_Face; */ /* it simply specifies the font driver to use for */ /* opening the face. If set to NULL, FreeType tries */ /* to load the face with each one of the drivers in */ /* its list. */ /* */ /* num_params :: The number of extra parameters. */ /* */ /* params :: Extra parameters passed to the font driver when */ /* opening a new face. */ /* */ /* <Note> */ /* The stream type is determined by the contents of `flags' that */ /* are tested in the following order by @FT_Open_Face: */ /* */ /* If the @FT_OPEN_MEMORY bit is set, assume that this is a */ /* memory file of `memory_size' bytes, located at `memory_address'. */ /* The data are not copied, and the client is responsible for */ /* releasing and destroying them _after_ the corresponding call to */ /* @FT_Done_Face. */ /* */ /* Otherwise, if the @FT_OPEN_STREAM bit is set, assume that a */ /* custom input stream `stream' is used. */ /* */ /* Otherwise, if the @FT_OPEN_PATHNAME bit is set, assume that this */ /* is a normal file and use `pathname' to open it. */ /* */ /* If the @FT_OPEN_DRIVER bit is set, @FT_Open_Face only tries to */ /* open the file with the driver whose handler is in `driver'. */ /* */ /* If the @FT_OPEN_PARAMS bit is set, the parameters given by */ /* `num_params' and `params' is used. They are ignored otherwise. */ /* */ /* Ideally, both the `pathname' and `params' fields should be tagged */ /* as `const'; this is missing for API backward compatibility. In */ /* other words, applications should treat them as read-only. */ /* */ typedef struct FT_Open_Args_ { FT_UInt flags; const FT_Byte* memory_base; FT_Long memory_size; FT_String* pathname; FT_Stream stream; FT_Module driver; FT_Int num_params; FT_Parameter* params; } FT_Open_Args; /*************************************************************************/ /* */ /* <Function> */ /* FT_New_Face */ /* */ /* <Description> */ /* Call @FT_Open_Face to open a font by its pathname. */ /* */ /* <InOut> */ /* library :: A handle to the library resource. */ /* */ /* <Input> */ /* pathname :: A path to the font file. */ /* */ /* face_index :: See @FT_Open_Face for a detailed description of this */ /* parameter. */ /* */ /* <Output> */ /* aface :: A handle to a new face object. If `face_index' is */ /* greater than or equal to zero, it must be non-NULL. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* Use @FT_Done_Face to destroy the created @FT_Face object (along */ /* with its slot and sizes). */ /* */ FT_EXPORT( FT_Error ) FT_New_Face( FT_Library library, const char* filepathname, FT_Long face_index, FT_Face *aface ); /*************************************************************************/ /* */ /* <Function> */ /* FT_New_Memory_Face */ /* */ /* <Description> */ /* Call @FT_Open_Face to open a font that has been loaded into */ /* memory. */ /* */ /* <InOut> */ /* library :: A handle to the library resource. */ /* */ /* <Input> */ /* file_base :: A pointer to the beginning of the font data. */ /* */ /* file_size :: The size of the memory chunk used by the font data. */ /* */ /* face_index :: See @FT_Open_Face for a detailed description of this */ /* parameter. */ /* */ /* <Output> */ /* aface :: A handle to a new face object. If `face_index' is */ /* greater than or equal to zero, it must be non-NULL. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* You must not deallocate the memory before calling @FT_Done_Face. */ /* */ FT_EXPORT( FT_Error ) FT_New_Memory_Face( FT_Library library, const FT_Byte* file_base, FT_Long file_size, FT_Long face_index, FT_Face *aface ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Open_Face */ /* */ /* <Description> */ /* Create a face object from a given resource described by */ /* @FT_Open_Args. */ /* */ /* <InOut> */ /* library :: A handle to the library resource. */ /* */ /* <Input> */ /* args :: A pointer to an `FT_Open_Args' structure that must */ /* be filled by the caller. */ /* */ /* face_index :: This field holds two different values. Bits 0-15 */ /* are the index of the face in the font file (starting */ /* with value~0). Set it to~0 if there is only one */ /* face in the font file. */ /* */ /* Bits 16-30 are relevant to GX and OpenType variation */ /* fonts only, specifying the named instance index for */ /* the current face index (starting with value~1; */ /* value~0 makes FreeType ignore named instances). For */ /* non-variation fonts, bits 16-30 are ignored. */ /* Assuming that you want to access the third named */ /* instance in face~4, `face_index' should be set to */ /* 0x00030004. If you want to access face~4 without */ /* variation handling, simply set `face_index' to */ /* value~4. */ /* */ /* `FT_Open_Face' and its siblings can be used to */ /* quickly check whether the font format of a given */ /* font resource is supported by FreeType. In general, */ /* if the `face_index' argument is negative, the */ /* function's return value is~0 if the font format is */ /* recognized, or non-zero otherwise. The function */ /* allocates a more or less empty face handle in */ /* `*aface' (if `aface' isn't NULL); the only two */ /* useful fields in this special case are */ /* `face->num_faces' and `face->style_flags'. For any */ /* negative value of `face_index', `face->num_faces' */ /* gives the number of faces within the font file. For */ /* the negative value `-(N+1)' (with `N' a non-negative */ /* 16-bit value), bits 16-30 in `face->style_flags' */ /* give the number of named instances in face `N' if we */ /* have a variation font (or zero otherwise). After */ /* examination, the returned @FT_Face structure should */ /* be deallocated with a call to @FT_Done_Face. */ /* */ /* <Output> */ /* aface :: A handle to a new face object. If `face_index' is */ /* greater than or equal to zero, it must be non-NULL. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* Unlike FreeType 1.x, this function automatically creates a glyph */ /* slot for the face object that can be accessed directly through */ /* `face->glyph'. */ /* */ /* Each new face object created with this function also owns a */ /* default @FT_Size object, accessible as `face->size'. */ /* */ /* One @FT_Library instance can have multiple face objects, this is, */ /* @FT_Open_Face and its siblings can be called multiple times using */ /* the same `library' argument. */ /* */ /* See the discussion of reference counters in the description of */ /* @FT_Reference_Face. */ /* */ /* To loop over all faces, use code similar to the following snippet */ /* (omitting the error handling). */ /* */ /* { */ /* ... */ /* FT_Face face; */ /* FT_Long i, num_faces; */ /* */ /* */ /* error = FT_Open_Face( library, args, -1, &face ); */ /* if ( error ) { ... } */ /* */ /* num_faces = face->num_faces; */ /* FT_Done_Face( face ); */ /* */ /* for ( i = 0; i < num_faces; i++ ) */ /* { */ /* ... */ /* error = FT_Open_Face( library, args, i, &face ); */ /* ... */ /* FT_Done_Face( face ); */ /* ... */ /* } */ /* } */ /* */ /* To loop over all valid values for `face_index', use something */ /* similar to the following snippet, again without error handling. */ /* The code accesses all faces immediately (thus only a single call */ /* of `FT_Open_Face' within the do-loop), with and without named */ /* instances. */ /* */ /* { */ /* ... */ /* FT_Face face; */ /* */ /* FT_Long num_faces = 0; */ /* FT_Long num_instances = 0; */ /* */ /* FT_Long face_idx = 0; */ /* FT_Long instance_idx = 0; */ /* */ /* */ /* do */ /* { */ /* FT_Long id = ( instance_idx << 16 ) + face_idx; */ /* */ /* */ /* error = FT_Open_Face( library, args, id, &face ); */ /* if ( error ) { ... } */ /* */ /* num_faces = face->num_faces; */ /* num_instances = face->style_flags >> 16; */ /* */ /* ... */ /* */ /* FT_Done_Face( face ); */ /* */ /* if ( instance_idx < num_instances ) */ /* instance_idx++; */ /* else */ /* { */ /* face_idx++; */ /* instance_idx = 0; */ /* } */ /* */ /* } while ( face_idx < num_faces ) */ /* } */ /* */ FT_EXPORT( FT_Error ) FT_Open_Face( FT_Library library, const FT_Open_Args* args, FT_Long face_index, FT_Face *aface ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Attach_File */ /* */ /* <Description> */ /* Call @FT_Attach_Stream to attach a file. */ /* */ /* <InOut> */ /* face :: The target face object. */ /* */ /* <Input> */ /* filepathname :: The pathname. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ FT_EXPORT( FT_Error ) FT_Attach_File( FT_Face face, const char* filepathname ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Attach_Stream */ /* */ /* <Description> */ /* `Attach' data to a face object. Normally, this is used to read */ /* additional information for the face object. For example, you can */ /* attach an AFM file that comes with a Type~1 font to get the */ /* kerning values and other metrics. */ /* */ /* <InOut> */ /* face :: The target face object. */ /* */ /* <Input> */ /* parameters :: A pointer to @FT_Open_Args that must be filled by */ /* the caller. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* The meaning of the `attach' (i.e., what really happens when the */ /* new file is read) is not fixed by FreeType itself. It really */ /* depends on the font format (and thus the font driver). */ /* */ /* Client applications are expected to know what they are doing */ /* when invoking this function. Most drivers simply do not implement */ /* file or stream attachments. */ /* */ FT_EXPORT( FT_Error ) FT_Attach_Stream( FT_Face face, FT_Open_Args* parameters ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Reference_Face */ /* */ /* <Description> */ /* A counter gets initialized to~1 at the time an @FT_Face structure */ /* is created. This function increments the counter. @FT_Done_Face */ /* then only destroys a face if the counter is~1, otherwise it simply */ /* decrements the counter. */ /* */ /* This function helps in managing life-cycles of structures that */ /* reference @FT_Face objects. */ /* */ /* <Input> */ /* face :: A handle to a target face object. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Since> */ /* 2.4.2 */ /* */ FT_EXPORT( FT_Error ) FT_Reference_Face( FT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Done_Face */ /* */ /* <Description> */ /* Discard a given face object, as well as all of its child slots and */ /* sizes. */ /* */ /* <Input> */ /* face :: A handle to a target face object. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* See the discussion of reference counters in the description of */ /* @FT_Reference_Face. */ /* */ FT_EXPORT( FT_Error ) FT_Done_Face( FT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Select_Size */ /* */ /* <Description> */ /* Select a bitmap strike. To be more precise, this function sets */ /* the scaling factors of the active @FT_Size object in a face so */ /* that bitmaps from this particular strike are taken by */ /* @FT_Load_Glyph and friends. */ /* */ /* <InOut> */ /* face :: A handle to a target face object. */ /* */ /* <Input> */ /* strike_index :: The index of the bitmap strike in the */ /* `available_sizes' field of @FT_FaceRec structure. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* For bitmaps embedded in outline fonts it is common that only a */ /* subset of the available glyphs at a given ppem value is available. */ /* FreeType silently uses outlines if there is no bitmap for a given */ /* glyph index. */ /* */ /* For GX and OpenType variation fonts, a bitmap strike makes sense */ /* only if the default instance is active (this is, no glyph */ /* variation takes place); otherwise, FreeType simply ignores bitmap */ /* strikes. The same is true for all named instances that are */ /* different from the default instance. */ /* */ /* Don't use this function if you are using the FreeType cache API. */ /* */ FT_EXPORT( FT_Error ) FT_Select_Size( FT_Face face, FT_Int strike_index ); /*************************************************************************/ /* */ /* <Enum> */ /* FT_Size_Request_Type */ /* */ /* <Description> */ /* An enumeration type that lists the supported size request types, */ /* i.e., what input size (in font units) maps to the requested output */ /* size (in pixels, as computed from the arguments of */ /* @FT_Size_Request). */ /* */ /* <Values> */ /* FT_SIZE_REQUEST_TYPE_NOMINAL :: */ /* The nominal size. The `units_per_EM' field of @FT_FaceRec is */ /* used to determine both scaling values. */ /* */ /* This is the standard scaling found in most applications. In */ /* particular, use this size request type for TrueType fonts if */ /* they provide optical scaling or something similar. Note, */ /* however, that `units_per_EM' is a rather abstract value which */ /* bears no relation to the actual size of the glyphs in a font. */ /* */ /* FT_SIZE_REQUEST_TYPE_REAL_DIM :: */ /* The real dimension. The sum of the `ascender' and (minus of) */ /* the `descender' fields of @FT_FaceRec is used to determine both */ /* scaling values. */ /* */ /* FT_SIZE_REQUEST_TYPE_BBOX :: */ /* The font bounding box. The width and height of the `bbox' field */ /* of @FT_FaceRec are used to determine the horizontal and vertical */ /* scaling value, respectively. */ /* */ /* FT_SIZE_REQUEST_TYPE_CELL :: */ /* The `max_advance_width' field of @FT_FaceRec is used to */ /* determine the horizontal scaling value; the vertical scaling */ /* value is determined the same way as */ /* @FT_SIZE_REQUEST_TYPE_REAL_DIM does. Finally, both scaling */ /* values are set to the smaller one. This type is useful if you */ /* want to specify the font size for, say, a window of a given */ /* dimension and 80x24 cells. */ /* */ /* FT_SIZE_REQUEST_TYPE_SCALES :: */ /* Specify the scaling values directly. */ /* */ /* <Note> */ /* The above descriptions only apply to scalable formats. For bitmap */ /* formats, the behaviour is up to the driver. */ /* */ /* See the note section of @FT_Size_Metrics if you wonder how size */ /* requesting relates to scaling values. */ /* */ typedef enum FT_Size_Request_Type_ { FT_SIZE_REQUEST_TYPE_NOMINAL, FT_SIZE_REQUEST_TYPE_REAL_DIM, FT_SIZE_REQUEST_TYPE_BBOX, FT_SIZE_REQUEST_TYPE_CELL, FT_SIZE_REQUEST_TYPE_SCALES, FT_SIZE_REQUEST_TYPE_MAX } FT_Size_Request_Type; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Size_RequestRec */ /* */ /* <Description> */ /* A structure to model a size request. */ /* */ /* <Fields> */ /* type :: See @FT_Size_Request_Type. */ /* */ /* width :: The desired width, given as a 26.6 fractional */ /* point value (with 72pt = 1in). */ /* */ /* height :: The desired height, given as a 26.6 fractional */ /* point value (with 72pt = 1in). */ /* */ /* horiResolution :: The horizontal resolution (dpi, i.e., pixels per */ /* inch). If set to zero, `width' is treated as a */ /* 26.6 fractional *pixel* value, which gets */ /* internally rounded to an integer. */ /* */ /* vertResolution :: The vertical resolution (dpi, i.e., pixels per */ /* inch). If set to zero, `height' is treated as a */ /* 26.6 fractional *pixel* value, which gets */ /* internally rounded to an integer. */ /* */ /* <Note> */ /* If `width' is zero, the horizontal scaling value is set equal */ /* to the vertical scaling value, and vice versa. */ /* */ /* If `type' is FT_SIZE_REQUEST_TYPE_SCALES, `width' and `height' are */ /* interpreted directly as 16.16 fractional scaling values, without */ /* any further modification, and both `horiResolution' and */ /* `vertResolution' are ignored. */ /* */ typedef struct FT_Size_RequestRec_ { FT_Size_Request_Type type; FT_Long width; FT_Long height; FT_UInt horiResolution; FT_UInt vertResolution; } FT_Size_RequestRec; /*************************************************************************/ /* */ /* <Struct> */ /* FT_Size_Request */ /* */ /* <Description> */ /* A handle to a size request structure. */ /* */ typedef struct FT_Size_RequestRec_ *FT_Size_Request; /*************************************************************************/ /* */ /* <Function> */ /* FT_Request_Size */ /* */ /* <Description> */ /* Resize the scale of the active @FT_Size object in a face. */ /* */ /* <InOut> */ /* face :: A handle to a target face object. */ /* */ /* <Input> */ /* req :: A pointer to a @FT_Size_RequestRec. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* Although drivers may select the bitmap strike matching the */ /* request, you should not rely on this if you intend to select a */ /* particular bitmap strike. Use @FT_Select_Size instead in that */ /* case. */ /* */ /* The relation between the requested size and the resulting glyph */ /* size is dependent entirely on how the size is defined in the */ /* source face. The font designer chooses the final size of each */ /* glyph relative to this size. For more information refer to */ /* `https://www.freetype.org/freetype2/docs/glyphs/glyphs-2.html'. */ /* */ /* Contrary to @FT_Set_Char_Size, this function doesn't have special */ /* code to normalize zero-valued widths, heights, or resolutions */ /* (which lead to errors in most cases). */ /* */ /* Don't use this function if you are using the FreeType cache API. */ /* */ FT_EXPORT( FT_Error ) FT_Request_Size( FT_Face face, FT_Size_Request req ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Set_Char_Size */ /* */ /* <Description> */ /* Call @FT_Request_Size to request the nominal size (in points). */ /* */ /* <InOut> */ /* face :: A handle to a target face object. */ /* */ /* <Input> */ /* char_width :: The nominal width, in 26.6 fractional points. */ /* */ /* char_height :: The nominal height, in 26.6 fractional points. */ /* */ /* horz_resolution :: The horizontal resolution in dpi. */ /* */ /* vert_resolution :: The vertical resolution in dpi. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* While this function allows fractional points as input values, the */ /* resulting ppem value for the given resolution is always rounded to */ /* the nearest integer. */ /* */ /* If either the character width or height is zero, it is set equal */ /* to the other value. */ /* */ /* If either the horizontal or vertical resolution is zero, it is set */ /* equal to the other value. */ /* */ /* A character width or height smaller than 1pt is set to 1pt; if */ /* both resolution values are zero, they are set to 72dpi. */ /* */ /* Don't use this function if you are using the FreeType cache API. */ /* */ FT_EXPORT( FT_Error ) FT_Set_Char_Size( FT_Face face, FT_F26Dot6 char_width, FT_F26Dot6 char_height, FT_UInt horz_resolution, FT_UInt vert_resolution ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Set_Pixel_Sizes */ /* */ /* <Description> */ /* Call @FT_Request_Size to request the nominal size (in pixels). */ /* */ /* <InOut> */ /* face :: A handle to the target face object. */ /* */ /* <Input> */ /* pixel_width :: The nominal width, in pixels. */ /* */ /* pixel_height :: The nominal height, in pixels. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* You should not rely on the resulting glyphs matching or being */ /* constrained to this pixel size. Refer to @FT_Request_Size to */ /* understand how requested sizes relate to actual sizes. */ /* */ /* Don't use this function if you are using the FreeType cache API. */ /* */ FT_EXPORT( FT_Error ) FT_Set_Pixel_Sizes( FT_Face face, FT_UInt pixel_width, FT_UInt pixel_height ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Load_Glyph */ /* */ /* <Description> */ /* Load a glyph into the glyph slot of a face object. */ /* */ /* <InOut> */ /* face :: A handle to the target face object where the glyph */ /* is loaded. */ /* */ /* <Input> */ /* glyph_index :: The index of the glyph in the font file. For */ /* CID-keyed fonts (either in PS or in CFF format) */ /* this argument specifies the CID value. */ /* */ /* load_flags :: A flag indicating what to load for this glyph. The */ /* @FT_LOAD_XXX constants can be used to control the */ /* glyph loading process (e.g., whether the outline */ /* should be scaled, whether to load bitmaps or not, */ /* whether to hint the outline, etc). */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* The loaded glyph may be transformed. See @FT_Set_Transform for */ /* the details. */ /* */ /* For subsetted CID-keyed fonts, `FT_Err_Invalid_Argument' is */ /* returned for invalid CID values (this is, for CID values that */ /* don't have a corresponding glyph in the font). See the discussion */ /* of the @FT_FACE_FLAG_CID_KEYED flag for more details. */ /* */ /* If you receive `FT_Err_Glyph_Too_Big', try getting the glyph */ /* outline at EM size, then scale it manually and fill it as a */ /* graphics operation. */ /* */ FT_EXPORT( FT_Error ) FT_Load_Glyph( FT_Face face, FT_UInt glyph_index, FT_Int32 load_flags ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Load_Char */ /* */ /* <Description> */ /* Load a glyph into the glyph slot of a face object, accessed by its */ /* character code. */ /* */ /* <InOut> */ /* face :: A handle to a target face object where the glyph */ /* is loaded. */ /* */ /* <Input> */ /* char_code :: The glyph's character code, according to the */ /* current charmap used in the face. */ /* */ /* load_flags :: A flag indicating what to load for this glyph. The */ /* @FT_LOAD_XXX constants can be used to control the */ /* glyph loading process (e.g., whether the outline */ /* should be scaled, whether to load bitmaps or not, */ /* whether to hint the outline, etc). */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* This function simply calls @FT_Get_Char_Index and @FT_Load_Glyph. */ /* */ /* Many fonts contain glyphs that can't be loaded by this function */ /* since its glyph indices are not listed in any of the font's */ /* charmaps. */ /* */ FT_EXPORT( FT_Error ) FT_Load_Char( FT_Face face, FT_ULong char_code, FT_Int32 load_flags ); /************************************************************************* * * @enum: * FT_LOAD_XXX * * @description: * A list of bit field constants for @FT_Load_Glyph to indicate what * kind of operations to perform during glyph loading. * * @values: * FT_LOAD_DEFAULT :: * Corresponding to~0, this value is used as the default glyph load * operation. In this case, the following happens: * * 1. FreeType looks for a bitmap for the glyph corresponding to the * face's current size. If one is found, the function returns. * The bitmap data can be accessed from the glyph slot (see note * below). * * 2. If no embedded bitmap is searched for or found, FreeType looks * for a scalable outline. If one is found, it is loaded from * the font file, scaled to device pixels, then `hinted' to the * pixel grid in order to optimize it. The outline data can be * accessed from the glyph slot (see note below). * * Note that by default the glyph loader doesn't render outlines into * bitmaps. The following flags are used to modify this default * behaviour to more specific and useful cases. * * FT_LOAD_NO_SCALE :: * Don't scale the loaded outline glyph but keep it in font units. * * This flag implies @FT_LOAD_NO_HINTING and @FT_LOAD_NO_BITMAP, and * unsets @FT_LOAD_RENDER. * * If the font is `tricky' (see @FT_FACE_FLAG_TRICKY for more), using * FT_LOAD_NO_SCALE usually yields meaningless outlines because the * subglyphs must be scaled and positioned with hinting instructions. * This can be solved by loading the font without FT_LOAD_NO_SCALE and * setting the character size to `font->units_per_EM'. * * FT_LOAD_NO_HINTING :: * Disable hinting. This generally generates `blurrier' bitmap glyphs * when the glyph are rendered in any of the anti-aliased modes. See * also the note below. * * This flag is implied by @FT_LOAD_NO_SCALE. * * FT_LOAD_RENDER :: * Call @FT_Render_Glyph after the glyph is loaded. By default, the * glyph is rendered in @FT_RENDER_MODE_NORMAL mode. This can be * overridden by @FT_LOAD_TARGET_XXX or @FT_LOAD_MONOCHROME. * * This flag is unset by @FT_LOAD_NO_SCALE. * * FT_LOAD_NO_BITMAP :: * Ignore bitmap strikes when loading. Bitmap-only fonts ignore this * flag. * * @FT_LOAD_NO_SCALE always sets this flag. * * FT_LOAD_VERTICAL_LAYOUT :: * Load the glyph for vertical text layout. In particular, the * `advance' value in the @FT_GlyphSlotRec structure is set to the * `vertAdvance' value of the `metrics' field. * * In case @FT_HAS_VERTICAL doesn't return true, you shouldn't use * this flag currently. Reason is that in this case vertical metrics * get synthesized, and those values are not always consistent across * various font formats. * * FT_LOAD_FORCE_AUTOHINT :: * Prefer the auto-hinter over the font's native hinter. See also * the note below. * * FT_LOAD_PEDANTIC :: * Make the font driver perform pedantic verifications during glyph * loading. This is mostly used to detect broken glyphs in fonts. * By default, FreeType tries to handle broken fonts also. * * In particular, errors from the TrueType bytecode engine are not * passed to the application if this flag is not set; this might * result in partially hinted or distorted glyphs in case a glyph's * bytecode is buggy. * * FT_LOAD_NO_RECURSE :: * Don't load composite glyphs recursively. Instead, the font * driver should set the `num_subglyph' and `subglyphs' values of * the glyph slot accordingly, and set `glyph->format' to * @FT_GLYPH_FORMAT_COMPOSITE. The description of subglyphs can * then be accessed with @FT_Get_SubGlyph_Info. * * This flag implies @FT_LOAD_NO_SCALE and @FT_LOAD_IGNORE_TRANSFORM. * * FT_LOAD_IGNORE_TRANSFORM :: * Ignore the transform matrix set by @FT_Set_Transform. * * FT_LOAD_MONOCHROME :: * This flag is used with @FT_LOAD_RENDER to indicate that you want to * render an outline glyph to a 1-bit monochrome bitmap glyph, with * 8~pixels packed into each byte of the bitmap data. * * Note that this has no effect on the hinting algorithm used. You * should rather use @FT_LOAD_TARGET_MONO so that the * monochrome-optimized hinting algorithm is used. * * FT_LOAD_LINEAR_DESIGN :: * Keep `linearHoriAdvance' and `linearVertAdvance' fields of * @FT_GlyphSlotRec in font units. See @FT_GlyphSlotRec for * details. * * FT_LOAD_NO_AUTOHINT :: * Disable the auto-hinter. See also the note below. * * FT_LOAD_COLOR :: * Load embedded color bitmap images. The resulting color bitmaps, * if available, will have the @FT_PIXEL_MODE_BGRA format. If the * flag is not set and color bitmaps are found, they are converted * to 256-level gray bitmaps transparently, using the * @FT_PIXEL_MODE_GRAY format. * * FT_LOAD_COMPUTE_METRICS :: * Compute glyph metrics from the glyph data, without the use of * bundled metrics tables (for example, the `hdmx' table in TrueType * fonts). This flag is mainly used by font validating or font * editing applications, which need to ignore, verify, or edit those * tables. * * Currently, this flag is only implemented for TrueType fonts. * * FT_LOAD_BITMAP_METRICS_ONLY :: * Request loading of the metrics and bitmap image information of a * (possibly embedded) bitmap glyph without allocating or copying * the bitmap image data itself. No effect if the target glyph is * not a bitmap image. * * This flag unsets @FT_LOAD_RENDER. * * FT_LOAD_CROP_BITMAP :: * Ignored. Deprecated. * * FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH :: * Ignored. Deprecated. * * @note: * By default, hinting is enabled and the font's native hinter (see * @FT_FACE_FLAG_HINTER) is preferred over the auto-hinter. You can * disable hinting by setting @FT_LOAD_NO_HINTING or change the * precedence by setting @FT_LOAD_FORCE_AUTOHINT. You can also set * @FT_LOAD_NO_AUTOHINT in case you don't want the auto-hinter to be * used at all. * * See the description of @FT_FACE_FLAG_TRICKY for a special exception * (affecting only a handful of Asian fonts). * * Besides deciding which hinter to use, you can also decide which * hinting algorithm to use. See @FT_LOAD_TARGET_XXX for details. * * Note that the auto-hinter needs a valid Unicode cmap (either a native * one or synthesized by FreeType) for producing correct results. If a * font provides an incorrect mapping (for example, assigning the * character code U+005A, LATIN CAPITAL LETTER Z, to a glyph depicting a * mathematical integral sign), the auto-hinter might produce useless * results. * */ #define FT_LOAD_DEFAULT 0x0 #define FT_LOAD_NO_SCALE ( 1L << 0 ) #define FT_LOAD_NO_HINTING ( 1L << 1 ) #define FT_LOAD_RENDER ( 1L << 2 ) #define FT_LOAD_NO_BITMAP ( 1L << 3 ) #define FT_LOAD_VERTICAL_LAYOUT ( 1L << 4 ) #define FT_LOAD_FORCE_AUTOHINT ( 1L << 5 ) #define FT_LOAD_CROP_BITMAP ( 1L << 6 ) #define FT_LOAD_PEDANTIC ( 1L << 7 ) #define FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ( 1L << 9 ) #define FT_LOAD_NO_RECURSE ( 1L << 10 ) #define FT_LOAD_IGNORE_TRANSFORM ( 1L << 11 ) #define FT_LOAD_MONOCHROME ( 1L << 12 ) #define FT_LOAD_LINEAR_DESIGN ( 1L << 13 ) #define FT_LOAD_NO_AUTOHINT ( 1L << 15 ) /* Bits 16-19 are used by `FT_LOAD_TARGET_' */ #define FT_LOAD_COLOR ( 1L << 20 ) #define FT_LOAD_COMPUTE_METRICS ( 1L << 21 ) #define FT_LOAD_BITMAP_METRICS_ONLY ( 1L << 22 ) /* */ /* used internally only by certain font drivers */ #define FT_LOAD_ADVANCE_ONLY ( 1L << 8 ) #define FT_LOAD_SBITS_ONLY ( 1L << 14 ) /************************************************************************** * * @enum: * FT_LOAD_TARGET_XXX * * @description: * A list of values to select a specific hinting algorithm for the * hinter. You should OR one of these values to your `load_flags' * when calling @FT_Load_Glyph. * * Note that a font's native hinters may ignore the hinting algorithm * you have specified (e.g., the TrueType bytecode interpreter). You * can set @FT_LOAD_FORCE_AUTOHINT to ensure that the auto-hinter is * used. * * @values: * FT_LOAD_TARGET_NORMAL :: * The default hinting algorithm, optimized for standard gray-level * rendering. For monochrome output, use @FT_LOAD_TARGET_MONO * instead. * * FT_LOAD_TARGET_LIGHT :: * A lighter hinting algorithm for gray-level modes. Many generated * glyphs are fuzzier but better resemble their original shape. This * is achieved by snapping glyphs to the pixel grid only vertically * (Y-axis), as is done by FreeType's new CFF engine or Microsoft's * ClearType font renderer. This preserves inter-glyph spacing in * horizontal text. The snapping is done either by the native font * driver, if the driver itself and the font support it, or by the * auto-hinter. * * Advance widths are rounded to integer values; however, using the * `lsb_delta' and `rsb_delta' fields of @FT_GlyphSlotRec, it is * possible to get fractional advance widths for sub-pixel positioning * (which is recommended to use). * * If configuration option AF_CONFIG_OPTION_TT_SIZE_METRICS is active, * TrueType-like metrics are used to make this mode behave similarly * as in unpatched FreeType versions between 2.4.6 and 2.7.1 * (inclusive). * * FT_LOAD_TARGET_MONO :: * Strong hinting algorithm that should only be used for monochrome * output. The result is probably unpleasant if the glyph is rendered * in non-monochrome modes. * * FT_LOAD_TARGET_LCD :: * A variant of @FT_LOAD_TARGET_LIGHT optimized for horizontally * decimated LCD displays. * * FT_LOAD_TARGET_LCD_V :: * A variant of @FT_LOAD_TARGET_NORMAL optimized for vertically * decimated LCD displays. * * @note: * You should use only _one_ of the FT_LOAD_TARGET_XXX values in your * `load_flags'. They can't be ORed. * * If @FT_LOAD_RENDER is also set, the glyph is rendered in the * corresponding mode (i.e., the mode that matches the used algorithm * best). An exception is FT_LOAD_TARGET_MONO since it implies * @FT_LOAD_MONOCHROME. * * You can use a hinting algorithm that doesn't correspond to the same * rendering mode. As an example, it is possible to use the `light' * hinting algorithm and have the results rendered in horizontal LCD * pixel mode, with code like * * { * FT_Load_Glyph( face, glyph_index, * load_flags | FT_LOAD_TARGET_LIGHT ); * * FT_Render_Glyph( face->glyph, FT_RENDER_MODE_LCD ); * } * * In general, you should stick with one rendering mode. For example, * switching between @FT_LOAD_TARGET_NORMAL and @FT_LOAD_TARGET_MONO * enforces a lot of recomputation for TrueType fonts, which is slow. * Another reason is caching: Selecting a different mode usually causes * changes in both the outlines and the rasterized bitmaps; it is thus * necessary to empty the cache after a mode switch to avoid false hits. * */ #define FT_LOAD_TARGET_( x ) ( (FT_Int32)( (x) & 15 ) << 16 ) #define FT_LOAD_TARGET_NORMAL FT_LOAD_TARGET_( FT_RENDER_MODE_NORMAL ) #define FT_LOAD_TARGET_LIGHT FT_LOAD_TARGET_( FT_RENDER_MODE_LIGHT ) #define FT_LOAD_TARGET_MONO FT_LOAD_TARGET_( FT_RENDER_MODE_MONO ) #define FT_LOAD_TARGET_LCD FT_LOAD_TARGET_( FT_RENDER_MODE_LCD ) #define FT_LOAD_TARGET_LCD_V FT_LOAD_TARGET_( FT_RENDER_MODE_LCD_V ) /************************************************************************** * * @macro: * FT_LOAD_TARGET_MODE * * @description: * Return the @FT_Render_Mode corresponding to a given * @FT_LOAD_TARGET_XXX value. * */ #define FT_LOAD_TARGET_MODE( x ) ( (FT_Render_Mode)( ( (x) >> 16 ) & 15 ) ) /*************************************************************************/ /* */ /* <Function> */ /* FT_Set_Transform */ /* */ /* <Description> */ /* Set the transformation that is applied to glyph images when they */ /* are loaded into a glyph slot through @FT_Load_Glyph. */ /* */ /* <InOut> */ /* face :: A handle to the source face object. */ /* */ /* <Input> */ /* matrix :: A pointer to the transformation's 2x2 matrix. Use NULL */ /* for the identity matrix. */ /* delta :: A pointer to the translation vector. Use NULL for the */ /* null vector. */ /* */ /* <Note> */ /* The transformation is only applied to scalable image formats after */ /* the glyph has been loaded. It means that hinting is unaltered by */ /* the transformation and is performed on the character size given in */ /* the last call to @FT_Set_Char_Size or @FT_Set_Pixel_Sizes. */ /* */ /* Note that this also transforms the `face.glyph.advance' field, but */ /* *not* the values in `face.glyph.metrics'. */ /* */ FT_EXPORT( void ) FT_Set_Transform( FT_Face face, FT_Matrix* matrix, FT_Vector* delta ); /*************************************************************************/ /* */ /* <Enum> */ /* FT_Render_Mode */ /* */ /* <Description> */ /* Render modes supported by FreeType~2. Each mode corresponds to a */ /* specific type of scanline conversion performed on the outline. */ /* */ /* For bitmap fonts and embedded bitmaps the `bitmap->pixel_mode' */ /* field in the @FT_GlyphSlotRec structure gives the format of the */ /* returned bitmap. */ /* */ /* All modes except @FT_RENDER_MODE_MONO use 256 levels of opacity, */ /* indicating pixel coverage. Use linear alpha blending and gamma */ /* correction to correctly render non-monochrome glyph bitmaps onto a */ /* surface; see @FT_Render_Glyph. */ /* */ /* <Values> */ /* FT_RENDER_MODE_NORMAL :: */ /* Default render mode; it corresponds to 8-bit anti-aliased */ /* bitmaps. */ /* */ /* FT_RENDER_MODE_LIGHT :: */ /* This is equivalent to @FT_RENDER_MODE_NORMAL. It is only */ /* defined as a separate value because render modes are also used */ /* indirectly to define hinting algorithm selectors. See */ /* @FT_LOAD_TARGET_XXX for details. */ /* */ /* FT_RENDER_MODE_MONO :: */ /* This mode corresponds to 1-bit bitmaps (with 2~levels of */ /* opacity). */ /* */ /* FT_RENDER_MODE_LCD :: */ /* This mode corresponds to horizontal RGB and BGR sub-pixel */ /* displays like LCD screens. It produces 8-bit bitmaps that are */ /* 3~times the width of the original glyph outline in pixels, and */ /* which use the @FT_PIXEL_MODE_LCD mode. */ /* */ /* FT_RENDER_MODE_LCD_V :: */ /* This mode corresponds to vertical RGB and BGR sub-pixel displays */ /* (like PDA screens, rotated LCD displays, etc.). It produces */ /* 8-bit bitmaps that are 3~times the height of the original */ /* glyph outline in pixels and use the @FT_PIXEL_MODE_LCD_V mode. */ /* */ /* <Note> */ /* The LCD-optimized glyph bitmaps produced by `FT_Render_Glyph' can */ /* be filtered to reduce color-fringes by using */ /* @FT_Library_SetLcdFilter (not active in the default builds). It */ /* is up to the caller to either call `FT_Library_SetLcdFilter' (if */ /* available) or do the filtering itself. */ /* */ /* The selected render mode only affects vector glyphs of a font. */ /* Embedded bitmaps often have a different pixel mode like */ /* @FT_PIXEL_MODE_MONO. You can use @FT_Bitmap_Convert to transform */ /* them into 8-bit pixmaps. */ /* */ typedef enum FT_Render_Mode_ { FT_RENDER_MODE_NORMAL = 0, FT_RENDER_MODE_LIGHT, FT_RENDER_MODE_MONO, FT_RENDER_MODE_LCD, FT_RENDER_MODE_LCD_V, FT_RENDER_MODE_MAX } FT_Render_Mode; /* these constants are deprecated; use the corresponding */ /* `FT_Render_Mode' values instead */ #define ft_render_mode_normal FT_RENDER_MODE_NORMAL #define ft_render_mode_mono FT_RENDER_MODE_MONO /*************************************************************************/ /* */ /* <Function> */ /* FT_Render_Glyph */ /* */ /* <Description> */ /* Convert a given glyph image to a bitmap. It does so by inspecting */ /* the glyph image format, finding the relevant renderer, and */ /* invoking it. */ /* */ /* <InOut> */ /* slot :: A handle to the glyph slot containing the image to */ /* convert. */ /* */ /* <Input> */ /* render_mode :: The render mode used to render the glyph image into */ /* a bitmap. See @FT_Render_Mode for a list of */ /* possible values. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* To get meaningful results, font scaling values must be set with */ /* functions like @FT_Set_Char_Size before calling `FT_Render_Glyph'. */ /* */ /* When FreeType outputs a bitmap of a glyph, it really outputs an */ /* alpha coverage map. If a pixel is completely covered by a */ /* filled-in outline, the bitmap contains 0xFF at that pixel, meaning */ /* that 0xFF/0xFF fraction of that pixel is covered, meaning the */ /* pixel is 100% black (or 0% bright). If a pixel is only 50% */ /* covered (value 0x80), the pixel is made 50% black (50% bright or a */ /* middle shade of grey). 0% covered means 0% black (100% bright or */ /* white). */ /* */ /* On high-DPI screens like on smartphones and tablets, the pixels */ /* are so small that their chance of being completely covered and */ /* therefore completely black are fairly good. On the low-DPI */ /* screens, however, the situation is different. The pixels are too */ /* large for most of the details of a glyph and shades of gray are */ /* the norm rather than the exception. */ /* */ /* This is relevant because all our screens have a second problem: */ /* they are not linear. 1~+~1 is not~2. Twice the value does not */ /* result in twice the brightness. When a pixel is only 50% covered, */ /* the coverage map says 50% black, and this translates to a pixel */ /* value of 128 when you use 8~bits per channel (0-255). However, */ /* this does not translate to 50% brightness for that pixel on our */ /* sRGB and gamma~2.2 screens. Due to their non-linearity, they */ /* dwell longer in the darks and only a pixel value of about 186 */ /* results in 50% brightness -- 128 ends up too dark on both bright */ /* and dark backgrounds. The net result is that dark text looks */ /* burnt-out, pixely and blotchy on bright background, bright text */ /* too frail on dark backgrounds, and colored text on colored */ /* background (for example, red on green) seems to have dark halos or */ /* `dirt' around it. The situation is especially ugly for diagonal */ /* stems like in `w' glyph shapes where the quality of FreeType's */ /* anti-aliasing depends on the correct display of grays. On */ /* high-DPI screens where smaller, fully black pixels reign supreme, */ /* this doesn't matter, but on our low-DPI screens with all the gray */ /* shades, it does. 0% and 100% brightness are the same things in */ /* linear and non-linear space, just all the shades in-between */ /* aren't. */ /* */ /* The blending function for placing text over a background is */ /* */ /* { */ /* dst = alpha * src + (1 - alpha) * dst , */ /* } */ /* */ /* which is known as the OVER operator. */ /* */ /* To correctly composite an antialiased pixel of a glyph onto a */ /* surface, */ /* */ /* 1. take the foreground and background colors (e.g., in sRGB space) */ /* and apply gamma to get them in a linear space, */ /* */ /* 2. use OVER to blend the two linear colors using the glyph pixel */ /* as the alpha value (remember, the glyph bitmap is an alpha */ /* coverage bitmap), and */ /* */ /* 3. apply inverse gamma to the blended pixel and write it back to */ /* the image. */ /* */ /* Internal testing at Adobe found that a target inverse gamma of~1.8 */ /* for step~3 gives good results across a wide range of displays with */ /* an sRGB gamma curve or a similar one. */ /* */ /* This process can cost performance. There is an approximation that */ /* does not need to know about the background color; see */ /* https://bel.fi/alankila/lcd/ and */ /* https://bel.fi/alankila/lcd/alpcor.html for details. */ /* */ /* *ATTENTION*: Linear blending is even more important when dealing */ /* with subpixel-rendered glyphs to prevent color-fringing! A */ /* subpixel-rendered glyph must first be filtered with a filter that */ /* gives equal weight to the three color primaries and does not */ /* exceed a sum of 0x100, see section @lcd_filtering. Then the */ /* only difference to gray linear blending is that subpixel-rendered */ /* linear blending is done 3~times per pixel: red foreground subpixel */ /* to red background subpixel and so on for green and blue. */ /* */ FT_EXPORT( FT_Error ) FT_Render_Glyph( FT_GlyphSlot slot, FT_Render_Mode render_mode ); /*************************************************************************/ /* */ /* <Enum> */ /* FT_Kerning_Mode */ /* */ /* <Description> */ /* An enumeration to specify the format of kerning values returned by */ /* @FT_Get_Kerning. */ /* */ /* <Values> */ /* FT_KERNING_DEFAULT :: Return grid-fitted kerning distances in */ /* 26.6 fractional pixels. */ /* */ /* FT_KERNING_UNFITTED :: Return un-grid-fitted kerning distances in */ /* 26.6 fractional pixels. */ /* */ /* FT_KERNING_UNSCALED :: Return the kerning vector in original font */ /* units. */ /* */ /* <Note> */ /* FT_KERNING_DEFAULT returns full pixel values; it also makes */ /* FreeType heuristically scale down kerning distances at small ppem */ /* values so that they don't become too big. */ /* */ /* Both FT_KERNING_DEFAULT and FT_KERNING_UNFITTED use the current */ /* horizontal scaling factor (as set e.g. with @FT_Set_Char_Size) to */ /* convert font units to pixels. */ /* */ typedef enum FT_Kerning_Mode_ { FT_KERNING_DEFAULT = 0, FT_KERNING_UNFITTED, FT_KERNING_UNSCALED } FT_Kerning_Mode; /* these constants are deprecated; use the corresponding */ /* `FT_Kerning_Mode' values instead */ #define ft_kerning_default FT_KERNING_DEFAULT #define ft_kerning_unfitted FT_KERNING_UNFITTED #define ft_kerning_unscaled FT_KERNING_UNSCALED /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Kerning */ /* */ /* <Description> */ /* Return the kerning vector between two glyphs of the same face. */ /* */ /* <Input> */ /* face :: A handle to a source face object. */ /* */ /* left_glyph :: The index of the left glyph in the kern pair. */ /* */ /* right_glyph :: The index of the right glyph in the kern pair. */ /* */ /* kern_mode :: See @FT_Kerning_Mode for more information. */ /* Determines the scale and dimension of the returned */ /* kerning vector. */ /* */ /* <Output> */ /* akerning :: The kerning vector. This is either in font units, */ /* fractional pixels (26.6 format), or pixels for */ /* scalable formats, and in pixels for fixed-sizes */ /* formats. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* Only horizontal layouts (left-to-right & right-to-left) are */ /* supported by this method. Other layouts, or more sophisticated */ /* kernings, are out of the scope of this API function -- they can be */ /* implemented through format-specific interfaces. */ /* */ /* Kerning for OpenType fonts implemented in a `GPOS' table is not */ /* supported; use @FT_HAS_KERNING to find out whether a font has data */ /* that can be extracted with `FT_Get_Kerning'. */ /* */ FT_EXPORT( FT_Error ) FT_Get_Kerning( FT_Face face, FT_UInt left_glyph, FT_UInt right_glyph, FT_UInt kern_mode, FT_Vector *akerning ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Track_Kerning */ /* */ /* <Description> */ /* Return the track kerning for a given face object at a given size. */ /* */ /* <Input> */ /* face :: A handle to a source face object. */ /* */ /* point_size :: The point size in 16.16 fractional points. */ /* */ /* degree :: The degree of tightness. Increasingly negative */ /* values represent tighter track kerning, while */ /* increasingly positive values represent looser track */ /* kerning. Value zero means no track kerning. */ /* */ /* <Output> */ /* akerning :: The kerning in 16.16 fractional points, to be */ /* uniformly applied between all glyphs. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* Currently, only the Type~1 font driver supports track kerning, */ /* using data from AFM files (if attached with @FT_Attach_File or */ /* @FT_Attach_Stream). */ /* */ /* Only very few AFM files come with track kerning data; please refer */ /* to Adobe's AFM specification for more details. */ /* */ FT_EXPORT( FT_Error ) FT_Get_Track_Kerning( FT_Face face, FT_Fixed point_size, FT_Int degree, FT_Fixed* akerning ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Glyph_Name */ /* */ /* <Description> */ /* Retrieve the ASCII name of a given glyph in a face. This only */ /* works for those faces where @FT_HAS_GLYPH_NAMES(face) returns~1. */ /* */ /* <Input> */ /* face :: A handle to a source face object. */ /* */ /* glyph_index :: The glyph index. */ /* */ /* buffer_max :: The maximum number of bytes available in the */ /* buffer. */ /* */ /* <Output> */ /* buffer :: A pointer to a target buffer where the name is */ /* copied to. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* An error is returned if the face doesn't provide glyph names or if */ /* the glyph index is invalid. In all cases of failure, the first */ /* byte of `buffer' is set to~0 to indicate an empty name. */ /* */ /* The glyph name is truncated to fit within the buffer if it is too */ /* long. The returned string is always zero-terminated. */ /* */ /* Be aware that FreeType reorders glyph indices internally so that */ /* glyph index~0 always corresponds to the `missing glyph' (called */ /* `.notdef'). */ /* */ /* This function always returns an error if the config macro */ /* `FT_CONFIG_OPTION_NO_GLYPH_NAMES' is not defined in `ftoption.h'. */ /* */ FT_EXPORT( FT_Error ) FT_Get_Glyph_Name( FT_Face face, FT_UInt glyph_index, FT_Pointer buffer, FT_UInt buffer_max ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Postscript_Name */ /* */ /* <Description> */ /* Retrieve the ASCII PostScript name of a given face, if available. */ /* This only works with PostScript, TrueType, and OpenType fonts. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* <Return> */ /* A pointer to the face's PostScript name. NULL if unavailable. */ /* */ /* <Note> */ /* The returned pointer is owned by the face and is destroyed with */ /* it. */ /* */ /* For variation fonts, this string changes if you select a different */ /* instance, and you have to call `FT_Get_PostScript_Name' again to */ /* retrieve it. FreeType follows Adobe TechNote #5902, `Generating */ /* PostScript Names for Fonts Using OpenType Font Variations'. */ /* */ /* http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/font/pdfs/5902.AdobePSNameGeneration.html */ /* */ FT_EXPORT( const char* ) FT_Get_Postscript_Name( FT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Select_Charmap */ /* */ /* <Description> */ /* Select a given charmap by its encoding tag (as listed in */ /* `freetype.h'). */ /* */ /* <InOut> */ /* face :: A handle to the source face object. */ /* */ /* <Input> */ /* encoding :: A handle to the selected encoding. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* This function returns an error if no charmap in the face */ /* corresponds to the encoding queried here. */ /* */ /* Because many fonts contain more than a single cmap for Unicode */ /* encoding, this function has some special code to select the one */ /* that covers Unicode best (`best' in the sense that a UCS-4 cmap is */ /* preferred to a UCS-2 cmap). It is thus preferable to */ /* @FT_Set_Charmap in this case. */ /* */ FT_EXPORT( FT_Error ) FT_Select_Charmap( FT_Face face, FT_Encoding encoding ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Set_Charmap */ /* */ /* <Description> */ /* Select a given charmap for character code to glyph index mapping. */ /* */ /* <InOut> */ /* face :: A handle to the source face object. */ /* */ /* <Input> */ /* charmap :: A handle to the selected charmap. */ /* */ /* <Return> */ /* FreeType error code. 0~means success. */ /* */ /* <Note> */ /* This function returns an error if the charmap is not part of */ /* the face (i.e., if it is not listed in the `face->charmaps' */ /* table). */ /* */ /* It also fails if an OpenType type~14 charmap is selected (which */ /* doesn't map character codes to glyph indices at all). */ /* */ FT_EXPORT( FT_Error ) FT_Set_Charmap( FT_Face face, FT_CharMap charmap ); /************************************************************************* * * @function: * FT_Get_Charmap_Index * * @description: * Retrieve index of a given charmap. * * @input: * charmap :: * A handle to a charmap. * * @return: * The index into the array of character maps within the face to which * `charmap' belongs. If an error occurs, -1 is returned. * */ FT_EXPORT( FT_Int ) FT_Get_Charmap_Index( FT_CharMap charmap ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Char_Index */ /* */ /* <Description> */ /* Return the glyph index of a given character code. This function */ /* uses the currently selected charmap to do the mapping. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* charcode :: The character code. */ /* */ /* <Return> */ /* The glyph index. 0~means `undefined character code'. */ /* */ /* <Note> */ /* If you use FreeType to manipulate the contents of font files */ /* directly, be aware that the glyph index returned by this function */ /* doesn't always correspond to the internal indices used within the */ /* file. This is done to ensure that value~0 always corresponds to */ /* the `missing glyph'. If the first glyph is not named `.notdef', */ /* then for Type~1 and Type~42 fonts, `.notdef' will be moved into */ /* the glyph ID~0 position, and whatever was there will be moved to */ /* the position `.notdef' had. For Type~1 fonts, if there is no */ /* `.notdef' glyph at all, then one will be created at index~0 and */ /* whatever was there will be moved to the last index -- Type~42 */ /* fonts are considered invalid under this condition. */ /* */ FT_EXPORT( FT_UInt ) FT_Get_Char_Index( FT_Face face, FT_ULong charcode ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_First_Char */ /* */ /* <Description> */ /* Return the first character code in the current charmap of a given */ /* face, together with its corresponding glyph index. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* <Output> */ /* agindex :: Glyph index of first character code. 0~if charmap is */ /* empty. */ /* */ /* <Return> */ /* The charmap's first character code. */ /* */ /* <Note> */ /* You should use this function together with @FT_Get_Next_Char to */ /* parse all character codes available in a given charmap. The code */ /* should look like this: */ /* */ /* { */ /* FT_ULong charcode; */ /* FT_UInt gindex; */ /* */ /* */ /* charcode = FT_Get_First_Char( face, &gindex ); */ /* while ( gindex != 0 ) */ /* { */ /* ... do something with (charcode,gindex) pair ... */ /* */ /* charcode = FT_Get_Next_Char( face, charcode, &gindex ); */ /* } */ /* } */ /* */ /* Be aware that character codes can have values up to 0xFFFFFFFF; */ /* this might happen for non-Unicode or malformed cmaps. However, */ /* even with regular Unicode encoding, so-called `last resort fonts' */ /* (using SFNT cmap format 13, see function @FT_Get_CMap_Format) */ /* normally have entries for all Unicode characters up to 0x1FFFFF, */ /* which can cause *a lot* of iterations. */ /* */ /* Note that `*agindex' is set to~0 if the charmap is empty. The */ /* result itself can be~0 in two cases: if the charmap is empty or */ /* if the value~0 is the first valid character code. */ /* */ FT_EXPORT( FT_ULong ) FT_Get_First_Char( FT_Face face, FT_UInt *agindex ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Next_Char */ /* */ /* <Description> */ /* Return the next character code in the current charmap of a given */ /* face following the value `char_code', as well as the corresponding */ /* glyph index. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* char_code :: The starting character code. */ /* */ /* <Output> */ /* agindex :: Glyph index of next character code. 0~if charmap */ /* is empty. */ /* */ /* <Return> */ /* The charmap's next character code. */ /* */ /* <Note> */ /* You should use this function with @FT_Get_First_Char to walk */ /* over all character codes available in a given charmap. See the */ /* note for that function for a simple code example. */ /* */ /* Note that `*agindex' is set to~0 when there are no more codes in */ /* the charmap. */ /* */ FT_EXPORT( FT_ULong ) FT_Get_Next_Char( FT_Face face, FT_ULong char_code, FT_UInt *agindex ); /************************************************************************* * * @function: * FT_Face_Properties * * @description: * Set or override certain (library or module-wide) properties on a * face-by-face basis. Useful for finer-grained control and avoiding * locks on shared structures (threads can modify their own faces as * they see fit). * * Contrary to @FT_Property_Set, this function uses @FT_Parameter so * that you can pass multiple properties to the target face in one call. * Note that only a subset of the available properties can be * controlled. * * * Stem darkening (@FT_PARAM_TAG_STEM_DARKENING, corresponding to the * property `no-stem-darkening' provided by the `autofit' and `cff' * modules; see @no-stem-darkening[autofit] and * @no-stem-darkening[cff]). * * * LCD filter weights (@FT_PARAM_TAG_LCD_FILTER_WEIGHTS, corresponding * to function @FT_Library_SetLcdFilterWeights). * * * Seed value for the CFF `random' operator * (@FT_PARAM_TAG_RANDOM_SEED, corresponding to the `random-seed' * property provided by the `cff' module; see @random-seed). * * Pass NULL as `data' in @FT_Parameter for a given tag to reset the * option and use the library or module default again. * * @input: * face :: * A handle to the source face object. * * num_properties :: * The number of properties that follow. * * properties :: * A handle to an @FT_Parameter array with `num_properties' elements. * * @return: * FreeType error code. 0~means success. * * @note: * Here an example that sets three properties. You must define * FT_CONFIG_OPTION_SUBPIXEL_RENDERING to make the LCD filter examples * work. * * { * FT_Parameter property1; * FT_Bool darken_stems = 1; * * FT_Parameter property2; * FT_LcdFiveTapFilter custom_weight = * { 0x11, 0x44, 0x56, 0x44, 0x11 }; * * FT_Parameter property3; * FT_Int32 random_seed = 314159265; * * FT_Parameter properties[3] = { property1, * property2, * property3 }; * * * property1.tag = FT_PARAM_TAG_STEM_DARKENING; * property1.data = &darken_stems; * * property2.tag = FT_PARAM_TAG_LCD_FILTER_WEIGHTS; * property2.data = custom_weight; * * property3.tag = FT_PARAM_TAG_RANDOM_SEED; * property3.data = &random_seed; * * FT_Face_Properties( face, 3, properties ); * } * * The next example resets a single property to its default value. * * { * FT_Parameter property; * * * property.tag = FT_PARAM_TAG_LCD_FILTER_WEIGHTS; * property.data = NULL; * * FT_Face_Properties( face, 1, &property ); * } * */ FT_EXPORT( FT_Error ) FT_Face_Properties( FT_Face face, FT_UInt num_properties, FT_Parameter* properties ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Name_Index */ /* */ /* <Description> */ /* Return the glyph index of a given glyph name. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* glyph_name :: The glyph name. */ /* */ /* <Return> */ /* The glyph index. 0~means `undefined character code'. */ /* */ FT_EXPORT( FT_UInt ) FT_Get_Name_Index( FT_Face face, FT_String* glyph_name ); /************************************************************************* * * @macro: * FT_SUBGLYPH_FLAG_XXX * * @description: * A list of constants describing subglyphs. Please refer to the * `glyf' table description in the OpenType specification for the * meaning of the various flags (which get synthesized for * non-OpenType subglyphs). * * @values: * FT_SUBGLYPH_FLAG_ARGS_ARE_WORDS :: * FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES :: * FT_SUBGLYPH_FLAG_ROUND_XY_TO_GRID :: * FT_SUBGLYPH_FLAG_SCALE :: * FT_SUBGLYPH_FLAG_XY_SCALE :: * FT_SUBGLYPH_FLAG_2X2 :: * FT_SUBGLYPH_FLAG_USE_MY_METRICS :: * */ #define FT_SUBGLYPH_FLAG_ARGS_ARE_WORDS 1 #define FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES 2 #define FT_SUBGLYPH_FLAG_ROUND_XY_TO_GRID 4 #define FT_SUBGLYPH_FLAG_SCALE 8 #define FT_SUBGLYPH_FLAG_XY_SCALE 0x40 #define FT_SUBGLYPH_FLAG_2X2 0x80 #define FT_SUBGLYPH_FLAG_USE_MY_METRICS 0x200 /************************************************************************* * * @func: * FT_Get_SubGlyph_Info * * @description: * Retrieve a description of a given subglyph. Only use it if * `glyph->format' is @FT_GLYPH_FORMAT_COMPOSITE; an error is * returned otherwise. * * @input: * glyph :: * The source glyph slot. * * sub_index :: * The index of the subglyph. Must be less than * `glyph->num_subglyphs'. * * @output: * p_index :: * The glyph index of the subglyph. * * p_flags :: * The subglyph flags, see @FT_SUBGLYPH_FLAG_XXX. * * p_arg1 :: * The subglyph's first argument (if any). * * p_arg2 :: * The subglyph's second argument (if any). * * p_transform :: * The subglyph transformation (if any). * * @return: * FreeType error code. 0~means success. * * @note: * The values of `*p_arg1', `*p_arg2', and `*p_transform' must be * interpreted depending on the flags returned in `*p_flags'. See the * OpenType specification for details. * */ FT_EXPORT( FT_Error ) FT_Get_SubGlyph_Info( FT_GlyphSlot glyph, FT_UInt sub_index, FT_Int *p_index, FT_UInt *p_flags, FT_Int *p_arg1, FT_Int *p_arg2, FT_Matrix *p_transform ); /*************************************************************************/ /* */ /* <Enum> */ /* FT_FSTYPE_XXX */ /* */ /* <Description> */ /* A list of bit flags used in the `fsType' field of the OS/2 table */ /* in a TrueType or OpenType font and the `FSType' entry in a */ /* PostScript font. These bit flags are returned by */ /* @FT_Get_FSType_Flags; they inform client applications of embedding */ /* and subsetting restrictions associated with a font. */ /* */ /* See */ /* http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/FontPolicies.pdf */ /* for more details. */ /* */ /* <Values> */ /* FT_FSTYPE_INSTALLABLE_EMBEDDING :: */ /* Fonts with no fsType bit set may be embedded and permanently */ /* installed on the remote system by an application. */ /* */ /* FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING :: */ /* Fonts that have only this bit set must not be modified, embedded */ /* or exchanged in any manner without first obtaining permission of */ /* the font software copyright owner. */ /* */ /* FT_FSTYPE_PREVIEW_AND_PRINT_EMBEDDING :: */ /* The font may be embedded and temporarily loaded on the remote */ /* system. Documents containing Preview & Print fonts must be */ /* opened `read-only'; no edits can be applied to the document. */ /* */ /* FT_FSTYPE_EDITABLE_EMBEDDING :: */ /* The font may be embedded but must only be installed temporarily */ /* on other systems. In contrast to Preview & Print fonts, */ /* documents containing editable fonts may be opened for reading, */ /* editing is permitted, and changes may be saved. */ /* */ /* FT_FSTYPE_NO_SUBSETTING :: */ /* The font may not be subsetted prior to embedding. */ /* */ /* FT_FSTYPE_BITMAP_EMBEDDING_ONLY :: */ /* Only bitmaps contained in the font may be embedded; no outline */ /* data may be embedded. If there are no bitmaps available in the */ /* font, then the font is unembeddable. */ /* */ /* <Note> */ /* The flags are ORed together, thus more than a single value can be */ /* returned. */ /* */ /* While the `fsType' flags can indicate that a font may be embedded, */ /* a license with the font vendor may be separately required to use */ /* the font in this way. */ /* */ #define FT_FSTYPE_INSTALLABLE_EMBEDDING 0x0000 #define FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING 0x0002 #define FT_FSTYPE_PREVIEW_AND_PRINT_EMBEDDING 0x0004 #define FT_FSTYPE_EDITABLE_EMBEDDING 0x0008 #define FT_FSTYPE_NO_SUBSETTING 0x0100 #define FT_FSTYPE_BITMAP_EMBEDDING_ONLY 0x0200 /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_FSType_Flags */ /* */ /* <Description> */ /* Return the `fsType' flags for a font. */ /* */ /* <Input> */ /* face :: A handle to the source face object. */ /* */ /* <Return> */ /* The `fsType' flags, see @FT_FSTYPE_XXX. */ /* */ /* <Note> */ /* Use this function rather than directly reading the `fs_type' field */ /* in the @PS_FontInfoRec structure, which is only guaranteed to */ /* return the correct results for Type~1 fonts. */ /* */ /* <Since> */ /* 2.3.8 */ /* */ FT_EXPORT( FT_UShort ) FT_Get_FSType_Flags( FT_Face face ); /*************************************************************************/ /* */ /* <Section> */ /* glyph_variants */ /* */ /* <Title> */ /* Unicode Variation Sequences */ /* */ /* <Abstract> */ /* The FreeType~2 interface to Unicode Variation Sequences (UVS), */ /* using the SFNT cmap format~14. */ /* */ /* <Description> */ /* Many characters, especially for CJK scripts, have variant forms. */ /* They are a sort of grey area somewhere between being totally */ /* irrelevant and semantically distinct; for this reason, the Unicode */ /* consortium decided to introduce Variation Sequences (VS), */ /* consisting of a Unicode base character and a variation selector */ /* instead of further extending the already huge number of */ /* characters. */ /* */ /* Unicode maintains two different sets, namely `Standardized */ /* Variation Sequences' and registered `Ideographic Variation */ /* Sequences' (IVS), collected in the `Ideographic Variation */ /* Database' (IVD). */ /* */ /* http://unicode.org/Public/UCD/latest/ucd/StandardizedVariants.txt */ /* http://unicode.org/reports/tr37/ */ /* http://unicode.org/ivd/ */ /* */ /* To date (January 2017), the character with the most ideographic */ /* variations is U+9089, having 32 such IVS. */ /* */ /* Three Mongolian Variation Selectors have the values U+180B-U+180D; */ /* 256 generic Variation Selectors are encoded in the ranges */ /* U+FE00-U+FE0F and U+E0100-U+E01EF. IVS currently use Variation */ /* Selectors from the range U+E0100-U+E01EF only. */ /* */ /* A VS consists of the base character value followed by a single */ /* Variation Selector. For example, to get the first variation of */ /* U+9089, you have to write the character sequence `U+9089 U+E0100'. */ /* */ /* Adobe and MS decided to support both standardized and ideographic */ /* VS with a new cmap subtable (format~14). It is an odd subtable */ /* because it is not a mapping of input code points to glyphs, but */ /* contains lists of all variations supported by the font. */ /* */ /* A variation may be either `default' or `non-default' for a given */ /* font. A default variation is the one you will get for that code */ /* point if you look it up in the standard Unicode cmap. A */ /* non-default variation is a different glyph. */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_GetCharVariantIndex */ /* */ /* <Description> */ /* Return the glyph index of a given character code as modified by */ /* the variation selector. */ /* */ /* <Input> */ /* face :: */ /* A handle to the source face object. */ /* */ /* charcode :: */ /* The character code point in Unicode. */ /* */ /* variantSelector :: */ /* The Unicode code point of the variation selector. */ /* */ /* <Return> */ /* The glyph index. 0~means either `undefined character code', or */ /* `undefined selector code', or `no variation selector cmap */ /* subtable', or `current CharMap is not Unicode'. */ /* */ /* <Note> */ /* If you use FreeType to manipulate the contents of font files */ /* directly, be aware that the glyph index returned by this function */ /* doesn't always correspond to the internal indices used within */ /* the file. This is done to ensure that value~0 always corresponds */ /* to the `missing glyph'. */ /* */ /* This function is only meaningful if */ /* a) the font has a variation selector cmap sub table, */ /* and */ /* b) the current charmap has a Unicode encoding. */ /* */ /* <Since> */ /* 2.3.6 */ /* */ FT_EXPORT( FT_UInt ) FT_Face_GetCharVariantIndex( FT_Face face, FT_ULong charcode, FT_ULong variantSelector ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_GetCharVariantIsDefault */ /* */ /* <Description> */ /* Check whether this variation of this Unicode character is the one */ /* to be found in the `cmap'. */ /* */ /* <Input> */ /* face :: */ /* A handle to the source face object. */ /* */ /* charcode :: */ /* The character codepoint in Unicode. */ /* */ /* variantSelector :: */ /* The Unicode codepoint of the variation selector. */ /* */ /* <Return> */ /* 1~if found in the standard (Unicode) cmap, 0~if found in the */ /* variation selector cmap, or -1 if it is not a variation. */ /* */ /* <Note> */ /* This function is only meaningful if the font has a variation */ /* selector cmap subtable. */ /* */ /* <Since> */ /* 2.3.6 */ /* */ FT_EXPORT( FT_Int ) FT_Face_GetCharVariantIsDefault( FT_Face face, FT_ULong charcode, FT_ULong variantSelector ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_GetVariantSelectors */ /* */ /* <Description> */ /* Return a zero-terminated list of Unicode variation selectors found */ /* in the font. */ /* */ /* <Input> */ /* face :: */ /* A handle to the source face object. */ /* */ /* <Return> */ /* A pointer to an array of selector code points, or NULL if there is */ /* no valid variation selector cmap subtable. */ /* */ /* <Note> */ /* The last item in the array is~0; the array is owned by the */ /* @FT_Face object but can be overwritten or released on the next */ /* call to a FreeType function. */ /* */ /* <Since> */ /* 2.3.6 */ /* */ FT_EXPORT( FT_UInt32* ) FT_Face_GetVariantSelectors( FT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_GetVariantsOfChar */ /* */ /* <Description> */ /* Return a zero-terminated list of Unicode variation selectors found */ /* for the specified character code. */ /* */ /* <Input> */ /* face :: */ /* A handle to the source face object. */ /* */ /* charcode :: */ /* The character codepoint in Unicode. */ /* */ /* <Return> */ /* A pointer to an array of variation selector code points that are */ /* active for the given character, or NULL if the corresponding list */ /* is empty. */ /* */ /* <Note> */ /* The last item in the array is~0; the array is owned by the */ /* @FT_Face object but can be overwritten or released on the next */ /* call to a FreeType function. */ /* */ /* <Since> */ /* 2.3.6 */ /* */ FT_EXPORT( FT_UInt32* ) FT_Face_GetVariantsOfChar( FT_Face face, FT_ULong charcode ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_GetCharsOfVariant */ /* */ /* <Description> */ /* Return a zero-terminated list of Unicode character codes found for */ /* the specified variation selector. */ /* */ /* <Input> */ /* face :: */ /* A handle to the source face object. */ /* */ /* variantSelector :: */ /* The variation selector code point in Unicode. */ /* */ /* <Return> */ /* A list of all the code points that are specified by this selector */ /* (both default and non-default codes are returned) or NULL if there */ /* is no valid cmap or the variation selector is invalid. */ /* */ /* <Note> */ /* The last item in the array is~0; the array is owned by the */ /* @FT_Face object but can be overwritten or released on the next */ /* call to a FreeType function. */ /* */ /* <Since> */ /* 2.3.6 */ /* */ FT_EXPORT( FT_UInt32* ) FT_Face_GetCharsOfVariant( FT_Face face, FT_ULong variantSelector ); /*************************************************************************/ /* */ /* <Section> */ /* computations */ /* */ /* <Title> */ /* Computations */ /* */ /* <Abstract> */ /* Crunching fixed numbers and vectors. */ /* */ /* <Description> */ /* This section contains various functions used to perform */ /* computations on 16.16 fixed-float numbers or 2d vectors. */ /* */ /* <Order> */ /* FT_MulDiv */ /* FT_MulFix */ /* FT_DivFix */ /* FT_RoundFix */ /* FT_CeilFix */ /* FT_FloorFix */ /* FT_Vector_Transform */ /* FT_Matrix_Multiply */ /* FT_Matrix_Invert */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* <Function> */ /* FT_MulDiv */ /* */ /* <Description> */ /* Compute `(a*b)/c' with maximum accuracy, using a 64-bit */ /* intermediate integer whenever necessary. */ /* */ /* This function isn't necessarily as fast as some processor specific */ /* operations, but is at least completely portable. */ /* */ /* <Input> */ /* a :: The first multiplier. */ /* */ /* b :: The second multiplier. */ /* */ /* c :: The divisor. */ /* */ /* <Return> */ /* The result of `(a*b)/c'. This function never traps when trying to */ /* divide by zero; it simply returns `MaxInt' or `MinInt' depending */ /* on the signs of `a' and `b'. */ /* */ FT_EXPORT( FT_Long ) FT_MulDiv( FT_Long a, FT_Long b, FT_Long c ); /*************************************************************************/ /* */ /* <Function> */ /* FT_MulFix */ /* */ /* <Description> */ /* Compute `(a*b)/0x10000' with maximum accuracy. Its main use is to */ /* multiply a given value by a 16.16 fixed-point factor. */ /* */ /* <Input> */ /* a :: The first multiplier. */ /* */ /* b :: The second multiplier. Use a 16.16 factor here whenever */ /* possible (see note below). */ /* */ /* <Return> */ /* The result of `(a*b)/0x10000'. */ /* */ /* <Note> */ /* This function has been optimized for the case where the absolute */ /* value of `a' is less than 2048, and `b' is a 16.16 scaling factor. */ /* As this happens mainly when scaling from notional units to */ /* fractional pixels in FreeType, it resulted in noticeable speed */ /* improvements between versions 2.x and 1.x. */ /* */ /* As a conclusion, always try to place a 16.16 factor as the */ /* _second_ argument of this function; this can make a great */ /* difference. */ /* */ FT_EXPORT( FT_Long ) FT_MulFix( FT_Long a, FT_Long b ); /*************************************************************************/ /* */ /* <Function> */ /* FT_DivFix */ /* */ /* <Description> */ /* Compute `(a*0x10000)/b' with maximum accuracy. Its main use is to */ /* divide a given value by a 16.16 fixed-point factor. */ /* */ /* <Input> */ /* a :: The numerator. */ /* */ /* b :: The denominator. Use a 16.16 factor here. */ /* */ /* <Return> */ /* The result of `(a*0x10000)/b'. */ /* */ FT_EXPORT( FT_Long ) FT_DivFix( FT_Long a, FT_Long b ); /*************************************************************************/ /* */ /* <Function> */ /* FT_RoundFix */ /* */ /* <Description> */ /* Round a 16.16 fixed number. */ /* */ /* <Input> */ /* a :: The number to be rounded. */ /* */ /* <Return> */ /* `a' rounded to the nearest 16.16 fixed integer, halfway cases away */ /* from zero. */ /* */ FT_EXPORT( FT_Fixed ) FT_RoundFix( FT_Fixed a ); /*************************************************************************/ /* */ /* <Function> */ /* FT_CeilFix */ /* */ /* <Description> */ /* Compute the smallest following integer of a 16.16 fixed number. */ /* */ /* <Input> */ /* a :: The number for which the ceiling function is to be computed. */ /* */ /* <Return> */ /* `a' rounded towards plus infinity. */ /* */ FT_EXPORT( FT_Fixed ) FT_CeilFix( FT_Fixed a ); /*************************************************************************/ /* */ /* <Function> */ /* FT_FloorFix */ /* */ /* <Description> */ /* Compute the largest previous integer of a 16.16 fixed number. */ /* */ /* <Input> */ /* a :: The number for which the floor function is to be computed. */ /* */ /* <Return> */ /* `a' rounded towards minus infinity. */ /* */ FT_EXPORT( FT_Fixed ) FT_FloorFix( FT_Fixed a ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Vector_Transform */ /* */ /* <Description> */ /* Transform a single vector through a 2x2 matrix. */ /* */ /* <InOut> */ /* vector :: The target vector to transform. */ /* */ /* <Input> */ /* matrix :: A pointer to the source 2x2 matrix. */ /* */ /* <Note> */ /* The result is undefined if either `vector' or `matrix' is invalid. */ /* */ FT_EXPORT( void ) FT_Vector_Transform( FT_Vector* vec, const FT_Matrix* matrix ); /*************************************************************************/ /* */ /* <Section> */ /* version */ /* */ /* <Title> */ /* FreeType Version */ /* */ /* <Abstract> */ /* Functions and macros related to FreeType versions. */ /* */ /* <Description> */ /* Note that those functions and macros are of limited use because */ /* even a new release of FreeType with only documentation changes */ /* increases the version number. */ /* */ /* <Order> */ /* FT_Library_Version */ /* */ /* FREETYPE_MAJOR */ /* FREETYPE_MINOR */ /* FREETYPE_PATCH */ /* */ /* FT_Face_CheckTrueTypePatents */ /* FT_Face_SetUnpatentedHinting */ /* */ /* FREETYPE_XXX */ /* */ /*************************************************************************/ /************************************************************************* * * @enum: * FREETYPE_XXX * * @description: * These three macros identify the FreeType source code version. * Use @FT_Library_Version to access them at runtime. * * @values: * FREETYPE_MAJOR :: The major version number. * FREETYPE_MINOR :: The minor version number. * FREETYPE_PATCH :: The patch level. * * @note: * The version number of FreeType if built as a dynamic link library * with the `libtool' package is _not_ controlled by these three * macros. * */ #define FREETYPE_MAJOR 2 #define FREETYPE_MINOR 8 #define FREETYPE_PATCH 0 /*************************************************************************/ /* */ /* <Function> */ /* FT_Library_Version */ /* */ /* <Description> */ /* Return the version of the FreeType library being used. This is */ /* useful when dynamically linking to the library, since one cannot */ /* use the macros @FREETYPE_MAJOR, @FREETYPE_MINOR, and */ /* @FREETYPE_PATCH. */ /* */ /* <Input> */ /* library :: A source library handle. */ /* */ /* <Output> */ /* amajor :: The major version number. */ /* */ /* aminor :: The minor version number. */ /* */ /* apatch :: The patch version number. */ /* */ /* <Note> */ /* The reason why this function takes a `library' argument is because */ /* certain programs implement library initialization in a custom way */ /* that doesn't use @FT_Init_FreeType. */ /* */ /* In such cases, the library version might not be available before */ /* the library object has been created. */ /* */ FT_EXPORT( void ) FT_Library_Version( FT_Library library, FT_Int *amajor, FT_Int *aminor, FT_Int *apatch ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_CheckTrueTypePatents */ /* */ /* <Description> */ /* Deprecated, does nothing. */ /* */ /* <Input> */ /* face :: A face handle. */ /* */ /* <Return> */ /* Always returns false. */ /* */ /* <Note> */ /* Since May 2010, TrueType hinting is no longer patented. */ /* */ /* <Since> */ /* 2.3.5 */ /* */ FT_EXPORT( FT_Bool ) FT_Face_CheckTrueTypePatents( FT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Face_SetUnpatentedHinting */ /* */ /* <Description> */ /* Deprecated, does nothing. */ /* */ /* <Input> */ /* face :: A face handle. */ /* */ /* value :: New boolean setting. */ /* */ /* <Return> */ /* Always returns false. */ /* */ /* <Note> */ /* Since May 2010, TrueType hinting is no longer patented. */ /* */ /* <Since> */ /* 2.3.5 */ /* */ FT_EXPORT( FT_Bool ) FT_Face_SetUnpatentedHinting( FT_Face face, FT_Bool value ); /* */ FT_END_HEADER #endif /* FREETYPE_H_ */ /* END */