ref: 22b1d5ca6772b155eaad79b0e0b406e308bd0d86
dir: /include/internal/sfnt.h/
/***************************************************************************/ /* */ /* sfnt.h */ /* */ /* High-level `sfnt' driver interface (specification). */ /* */ /* Copyright 1996-2015 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 __SFNT_H__ #define __SFNT_H__ #include <ft2build.h> #include FT_INTERNAL_DRIVER_H #include FT_INTERNAL_TRUETYPE_TYPES_H FT_BEGIN_HEADER /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Init_Face_Func */ /* */ /* <Description> */ /* First part of the SFNT face object initialization. This finds */ /* the face in a SFNT file or collection, and load its format tag in */ /* face->format_tag. */ /* */ /* <Input> */ /* stream :: The input stream. */ /* */ /* face :: A handle to the target face object. */ /* */ /* face_index :: The index of the TrueType font, if we are opening a */ /* collection. */ /* */ /* num_params :: The number of additional parameters. */ /* */ /* params :: Optional additional parameters. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The stream cursor must be at the font file's origin. */ /* */ /* This function recognizes fonts embedded in a `TrueType */ /* collection'. */ /* */ /* Once the format tag has been validated by the font driver, it */ /* should then call the TT_Load_Face_Func() callback to read the rest */ /* of the SFNT tables in the object. */ /* */ typedef FT_Error (*TT_Init_Face_Func)( FT_Stream stream, TT_Face face, FT_Int face_index, FT_Int num_params, FT_Parameter* params ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_Face_Func */ /* */ /* <Description> */ /* Second part of the SFNT face object initialization. This loads */ /* the common SFNT tables (head, OS/2, maxp, metrics, etc.) in the */ /* face object. */ /* */ /* <Input> */ /* stream :: The input stream. */ /* */ /* face :: A handle to the target face object. */ /* */ /* face_index :: The index of the TrueType font, if we are opening a */ /* collection. */ /* */ /* num_params :: The number of additional parameters. */ /* */ /* params :: Optional additional parameters. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* This function must be called after TT_Init_Face_Func(). */ /* */ typedef FT_Error (*TT_Load_Face_Func)( FT_Stream stream, TT_Face face, FT_Int face_index, FT_Int num_params, FT_Parameter* params ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Done_Face_Func */ /* */ /* <Description> */ /* A callback used to delete the common SFNT data from a face. */ /* */ /* <Input> */ /* face :: A handle to the target face object. */ /* */ /* <Note> */ /* This function does NOT destroy the face object. */ /* */ typedef void (*TT_Done_Face_Func)( TT_Face face ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_Any_Func */ /* */ /* <Description> */ /* Load any font table into client memory. */ /* */ /* <Input> */ /* face :: The face object to look for. */ /* */ /* tag :: The tag of table to load. Use the value 0 if you want */ /* to access the whole font file, else set this parameter */ /* to a valid TrueType table tag that you can forge with */ /* the MAKE_TT_TAG macro. */ /* */ /* offset :: The starting offset in the table (or the file if */ /* tag == 0). */ /* */ /* length :: The address of the decision variable: */ /* */ /* If length == NULL: */ /* Loads the whole table. Returns an error if */ /* `offset' == 0! */ /* */ /* If *length == 0: */ /* Exits immediately; returning the length of the given */ /* table or of the font file, depending on the value of */ /* `tag'. */ /* */ /* If *length != 0: */ /* Loads the next `length' bytes of table or font, */ /* starting at offset `offset' (in table or font too). */ /* */ /* <Output> */ /* buffer :: The address of target buffer. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ typedef FT_Error (*TT_Load_Any_Func)( TT_Face face, FT_ULong tag, FT_Long offset, FT_Byte *buffer, FT_ULong* length ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Find_SBit_Image_Func */ /* */ /* <Description> */ /* Check whether an embedded bitmap (an `sbit') exists for a given */ /* glyph, at a given strike. */ /* */ /* <Input> */ /* face :: The target face object. */ /* */ /* glyph_index :: The glyph index. */ /* */ /* strike_index :: The current strike index. */ /* */ /* <Output> */ /* arange :: The SBit range containing the glyph index. */ /* */ /* astrike :: The SBit strike containing the glyph index. */ /* */ /* aglyph_offset :: The offset of the glyph data in `EBDT' table. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. Returns */ /* SFNT_Err_Invalid_Argument if no sbit exists for the requested */ /* glyph. */ /* */ typedef FT_Error (*TT_Find_SBit_Image_Func)( TT_Face face, FT_UInt glyph_index, FT_ULong strike_index, TT_SBit_Range *arange, TT_SBit_Strike *astrike, FT_ULong *aglyph_offset ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_SBit_Metrics_Func */ /* */ /* <Description> */ /* Get the big metrics for a given embedded bitmap. */ /* */ /* <Input> */ /* stream :: The input stream. */ /* */ /* range :: The SBit range containing the glyph. */ /* */ /* <Output> */ /* big_metrics :: A big SBit metrics structure for the glyph. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The stream cursor must be positioned at the glyph's offset within */ /* the `EBDT' table before the call. */ /* */ /* If the image format uses variable metrics, the stream cursor is */ /* positioned just after the metrics header in the `EBDT' table on */ /* function exit. */ /* */ typedef FT_Error (*TT_Load_SBit_Metrics_Func)( FT_Stream stream, TT_SBit_Range range, TT_SBit_Metrics metrics ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_SBit_Image_Func */ /* */ /* <Description> */ /* Load a given glyph sbit image from the font resource. This also */ /* returns its metrics. */ /* */ /* <Input> */ /* face :: */ /* The target face object. */ /* */ /* strike_index :: */ /* The strike index. */ /* */ /* glyph_index :: */ /* The current glyph index. */ /* */ /* load_flags :: */ /* The current load flags. */ /* */ /* stream :: */ /* The input stream. */ /* */ /* <Output> */ /* amap :: */ /* The target pixmap. */ /* */ /* ametrics :: */ /* A big sbit metrics structure for the glyph image. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. Returns an error if no */ /* glyph sbit exists for the index. */ /* */ /* <Note> */ /* The `map.buffer' field is always freed before the glyph is loaded. */ /* */ typedef FT_Error (*TT_Load_SBit_Image_Func)( TT_Face face, FT_ULong strike_index, FT_UInt glyph_index, FT_UInt load_flags, FT_Stream stream, FT_Bitmap *amap, TT_SBit_MetricsRec *ametrics ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Set_SBit_Strike_Func */ /* */ /* <Description> */ /* Select an sbit strike for a given size request. */ /* */ /* <Input> */ /* face :: The target face object. */ /* */ /* req :: The size request. */ /* */ /* <Output> */ /* astrike_index :: The index of the sbit strike. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. Returns an error if no */ /* sbit strike exists for the selected ppem values. */ /* */ typedef FT_Error (*TT_Set_SBit_Strike_Func)( TT_Face face, FT_Size_Request req, FT_ULong* astrike_index ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_Strike_Metrics_Func */ /* */ /* <Description> */ /* Load the metrics of a given strike. */ /* */ /* <Input> */ /* face :: The target face object. */ /* */ /* strike_index :: The strike index. */ /* */ /* <Output> */ /* metrics :: the metrics of the strike. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. Returns an error if no */ /* such sbit strike exists. */ /* */ typedef FT_Error (*TT_Load_Strike_Metrics_Func)( TT_Face face, FT_ULong strike_index, FT_Size_Metrics* metrics ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Get_PS_Name_Func */ /* */ /* <Description> */ /* Get the PostScript glyph name of a glyph. */ /* */ /* <Input> */ /* idx :: The glyph index. */ /* */ /* PSname :: The address of a string pointer. Will be NULL in case */ /* of error, otherwise it is a pointer to the glyph name. */ /* */ /* You must not modify the returned string! */ /* */ /* <Output> */ /* FreeType error code. 0 means success. */ /* */ typedef FT_Error (*TT_Get_PS_Name_Func)( TT_Face face, FT_UInt idx, FT_String** PSname ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_Metrics_Func */ /* */ /* <Description> */ /* Load a metrics table, which is a table with a horizontal and a */ /* vertical version. */ /* */ /* <Input> */ /* face :: A handle to the target face object. */ /* */ /* stream :: The input stream. */ /* */ /* vertical :: A boolean flag. If set, load the vertical one. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ typedef FT_Error (*TT_Load_Metrics_Func)( TT_Face face, FT_Stream stream, FT_Bool vertical ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Get_Metrics_Func */ /* */ /* <Description> */ /* Load the horizontal or vertical header in a face object. */ /* */ /* <Input> */ /* face :: A handle to the target face object. */ /* */ /* vertical :: A boolean flag. If set, load vertical metrics. */ /* */ /* gindex :: The glyph index. */ /* */ /* <Output> */ /* abearing :: The horizontal (or vertical) bearing. Set to zero in */ /* case of error. */ /* */ /* aadvance :: The horizontal (or vertical) advance. Set to zero in */ /* case of error. */ /* */ typedef void (*TT_Get_Metrics_Func)( TT_Face face, FT_Bool vertical, FT_UInt gindex, FT_Short* abearing, FT_UShort* aadvance ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Load_Table_Func */ /* */ /* <Description> */ /* Load a given TrueType table. */ /* */ /* <Input> */ /* face :: A handle to the target face object. */ /* */ /* stream :: The input stream. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* The function uses `face->goto_table' to seek the stream to the */ /* start of the table, except while loading the font directory. */ /* */ typedef FT_Error (*TT_Load_Table_Func)( TT_Face face, FT_Stream stream ); /*************************************************************************/ /* */ /* <FuncType> */ /* TT_Free_Table_Func */ /* */ /* <Description> */ /* Free a given TrueType table. */ /* */ /* <Input> */ /* face :: A handle to the target face object. */ /* */ typedef void (*TT_Free_Table_Func)( TT_Face face ); /* * @functype: * TT_Face_GetKerningFunc * * @description: * Return the horizontal kerning value between two glyphs. * * @input: * face :: A handle to the source face object. * left_glyph :: The left glyph index. * right_glyph :: The right glyph index. * * @return: * The kerning value in font units. */ typedef FT_Int (*TT_Face_GetKerningFunc)( TT_Face face, FT_UInt left_glyph, FT_UInt right_glyph ); /*************************************************************************/ /* */ /* <Struct> */ /* SFNT_Interface */ /* */ /* <Description> */ /* This structure holds pointers to the functions used to load and */ /* free the basic tables that are required in a `sfnt' font file. */ /* */ /* <Fields> */ /* Check the various xxx_Func() descriptions for details. */ /* */ typedef struct SFNT_Interface_ { TT_Loader_GotoTableFunc goto_table; TT_Init_Face_Func init_face; TT_Load_Face_Func load_face; TT_Done_Face_Func done_face; FT_Module_Requester get_interface; TT_Load_Any_Func load_any; /* these functions are called by `load_face' but they can also */ /* be called from external modules, if there is a need to do so */ TT_Load_Table_Func load_head; TT_Load_Metrics_Func load_hhea; TT_Load_Table_Func load_cmap; TT_Load_Table_Func load_maxp; TT_Load_Table_Func load_os2; TT_Load_Table_Func load_post; TT_Load_Table_Func load_name; TT_Free_Table_Func free_name; /* this field was called `load_kerning' up to version 2.1.10 */ TT_Load_Table_Func load_kern; TT_Load_Table_Func load_gasp; TT_Load_Table_Func load_pclt; /* see `ttload.h'; this field was called `load_bitmap_header' up to */ /* version 2.1.10 */ TT_Load_Table_Func load_bhed; TT_Load_SBit_Image_Func load_sbit_image; /* see `ttpost.h' */ TT_Get_PS_Name_Func get_psname; TT_Free_Table_Func free_psnames; /* starting here, the structure differs from version 2.1.7 */ /* this field was introduced in version 2.1.8, named `get_psname' */ TT_Face_GetKerningFunc get_kerning; /* new elements introduced after version 2.1.10 */ /* load the font directory, i.e., the offset table and */ /* the table directory */ TT_Load_Table_Func load_font_dir; TT_Load_Metrics_Func load_hmtx; TT_Load_Table_Func load_eblc; TT_Free_Table_Func free_eblc; TT_Set_SBit_Strike_Func set_sbit_strike; TT_Load_Strike_Metrics_Func load_strike_metrics; TT_Get_Metrics_Func get_metrics; } SFNT_Interface; /* transitional */ typedef SFNT_Interface* SFNT_Service; #ifndef FT_CONFIG_OPTION_PIC #define FT_DEFINE_SFNT_INTERFACE( \ class_, \ goto_table_, \ init_face_, \ load_face_, \ done_face_, \ get_interface_, \ load_any_, \ load_head_, \ load_hhea_, \ load_cmap_, \ load_maxp_, \ load_os2_, \ load_post_, \ load_name_, \ free_name_, \ load_kern_, \ load_gasp_, \ load_pclt_, \ load_bhed_, \ load_sbit_image_, \ get_psname_, \ free_psnames_, \ get_kerning_, \ load_font_dir_, \ load_hmtx_, \ load_eblc_, \ free_eblc_, \ set_sbit_strike_, \ load_strike_metrics_, \ get_metrics_ ) \ static const SFNT_Interface class_ = \ { \ goto_table_, \ init_face_, \ load_face_, \ done_face_, \ get_interface_, \ load_any_, \ load_head_, \ load_hhea_, \ load_cmap_, \ load_maxp_, \ load_os2_, \ load_post_, \ load_name_, \ free_name_, \ load_kern_, \ load_gasp_, \ load_pclt_, \ load_bhed_, \ load_sbit_image_, \ get_psname_, \ free_psnames_, \ get_kerning_, \ load_font_dir_, \ load_hmtx_, \ load_eblc_, \ free_eblc_, \ set_sbit_strike_, \ load_strike_metrics_, \ get_metrics_, \ }; #else /* FT_CONFIG_OPTION_PIC */ #define FT_INTERNAL( a, a_ ) \ clazz->a = a_; #define FT_DEFINE_SFNT_INTERFACE( \ class_, \ goto_table_, \ init_face_, \ load_face_, \ done_face_, \ get_interface_, \ load_any_, \ load_head_, \ load_hhea_, \ load_cmap_, \ load_maxp_, \ load_os2_, \ load_post_, \ load_name_, \ free_name_, \ load_kern_, \ load_gasp_, \ load_pclt_, \ load_bhed_, \ load_sbit_image_, \ get_psname_, \ free_psnames_, \ get_kerning_, \ load_font_dir_, \ load_hmtx_, \ load_eblc_, \ free_eblc_, \ set_sbit_strike_, \ load_strike_metrics_, \ get_metrics_ ) \ void \ FT_Init_Class_ ## class_( FT_Library library, \ SFNT_Interface* clazz ) \ { \ FT_UNUSED( library ); \ \ clazz->goto_table = goto_table_; \ clazz->init_face = init_face_; \ clazz->load_face = load_face_; \ clazz->done_face = done_face_; \ clazz->get_interface = get_interface_; \ clazz->load_any = load_any_; \ clazz->load_head = load_head_; \ clazz->load_hhea = load_hhea_; \ clazz->load_cmap = load_cmap_; \ clazz->load_maxp = load_maxp_; \ clazz->load_os2 = load_os2_; \ clazz->load_post = load_post_; \ clazz->load_name = load_name_; \ clazz->free_name = free_name_; \ clazz->load_kern = load_kern_; \ clazz->load_gasp = load_gasp_; \ clazz->load_pclt = load_pclt_; \ clazz->load_bhed = load_bhed_; \ clazz->load_sbit_image = load_sbit_image_; \ clazz->get_psname = get_psname_; \ clazz->free_psnames = free_psnames_; \ clazz->get_kerning = get_kerning_; \ clazz->load_font_dir = load_font_dir_; \ clazz->load_hmtx = load_hmtx_; \ clazz->load_eblc = load_eblc_; \ clazz->free_eblc = free_eblc_; \ clazz->set_sbit_strike = set_sbit_strike_; \ clazz->load_strike_metrics = load_strike_metrics_; \ clazz->get_metrics = get_metrics_; \ } #endif /* FT_CONFIG_OPTION_PIC */ FT_END_HEADER #endif /* __SFNT_H__ */ /* END */