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Editing: ftadvanc.h
/***************************************************************************/ /* */ /* ftadvanc.h */ /* */ /* Quick computation of advance widths (specification only). */ /* */ /* Copyright 2008-2018 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 FTADVANC_H_ #define FTADVANC_H_ #include <ft2build.h> #include FT_FREETYPE_H #ifdef FREETYPE_H #error "freetype.h of FreeType 1 has been loaded!" #error "Please fix the directory search order for header files" #error "so that freetype.h of FreeType 2 is found first." #endif FT_BEGIN_HEADER /************************************************************************** * * @section: * quick_advance * * @title: * Quick retrieval of advance values * * @abstract: * Retrieve horizontal and vertical advance values without processing * glyph outlines, if possible. * * @description: * This section contains functions to quickly extract advance values * without handling glyph outlines, if possible. * * @order: * FT_Get_Advance * FT_Get_Advances * */ /*************************************************************************/ /* */ /* <Const> */ /* FT_ADVANCE_FLAG_FAST_ONLY */ /* */ /* <Description> */ /* A bit-flag to be OR-ed with the `flags' parameter of the */ /* @FT_Get_Advance and @FT_Get_Advances functions. */ /* */ /* If set, it indicates that you want these functions to fail if the */ /* corresponding hinting mode or font driver doesn't allow for very */ /* quick advance computation. */ /* */ /* Typically, glyphs that are either unscaled, unhinted, bitmapped, */ /* or light-hinted can have their advance width computed very */ /* quickly. */ /* */ /* Normal and bytecode hinted modes that require loading, scaling, */ /* and hinting of the glyph outline, are extremely slow by */ /* comparison. */ /* */ #define FT_ADVANCE_FLAG_FAST_ONLY 0x20000000L /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Advance */ /* */ /* <Description> */ /* Retrieve the advance value of a given glyph outline in an */ /* @FT_Face. */ /* */ /* <Input> */ /* face :: The source @FT_Face handle. */ /* */ /* gindex :: The glyph index. */ /* */ /* load_flags :: A set of bit flags similar to those used when */ /* calling @FT_Load_Glyph, used to determine what kind */ /* of advances you need. */ /* <Output> */ /* padvance :: The advance value. If scaling is performed (based on */ /* the value of `load_flags'), the advance value is in */ /* 16.16 format. Otherwise, it is in font units. */ /* */ /* If @FT_LOAD_VERTICAL_LAYOUT is set, this is the */ /* vertical advance corresponding to a vertical layout. */ /* Otherwise, it is the horizontal advance in a */ /* horizontal layout. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* This function may fail if you use @FT_ADVANCE_FLAG_FAST_ONLY and */ /* if the corresponding font backend doesn't have a quick way to */ /* retrieve the advances. */ /* */ /* A scaled advance is returned in 16.16 format but isn't transformed */ /* by the affine transformation specified by @FT_Set_Transform. */ /* */ FT_EXPORT( FT_Error ) FT_Get_Advance( FT_Face face, FT_UInt gindex, FT_Int32 load_flags, FT_Fixed *padvance ); /*************************************************************************/ /* */ /* <Function> */ /* FT_Get_Advances */ /* */ /* <Description> */ /* Retrieve the advance values of several glyph outlines in an */ /* @FT_Face. */ /* */ /* <Input> */ /* face :: The source @FT_Face handle. */ /* */ /* start :: The first glyph index. */ /* */ /* count :: The number of advance values you want to retrieve. */ /* */ /* load_flags :: A set of bit flags similar to those used when */ /* calling @FT_Load_Glyph. */ /* */ /* <Output> */ /* padvance :: The advance values. This array, to be provided by the */ /* caller, must contain at least `count' elements. */ /* */ /* If scaling is performed (based on the value of */ /* `load_flags'), the advance values are in 16.16 format. */ /* Otherwise, they are in font units. */ /* */ /* If @FT_LOAD_VERTICAL_LAYOUT is set, these are the */ /* vertical advances corresponding to a vertical layout. */ /* Otherwise, they are the horizontal advances in a */ /* horizontal layout. */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ /* <Note> */ /* This function may fail if you use @FT_ADVANCE_FLAG_FAST_ONLY and */ /* if the corresponding font backend doesn't have a quick way to */ /* retrieve the advances. */ /* */ /* Scaled advances are returned in 16.16 format but aren't */ /* transformed by the affine transformation specified by */ /* @FT_Set_Transform. */ /* */ FT_EXPORT( FT_Error ) FT_Get_Advances( FT_Face face, FT_UInt start, FT_UInt count, FT_Int32 load_flags, FT_Fixed *padvances ); /* */ FT_END_HEADER #endif /* FTADVANC_H_ */ /* END */
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