00001 /***************************************************************************/ 00002 /* */ 00003 /* ftgasp.h */ 00004 /* */ 00005 /* Access of TrueType's `gasp' table (specification). */ 00006 /* */ 00007 /* Copyright 2007, 2008 by */ 00008 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 00009 /* */ 00010 /* This file is part of the FreeType project, and may only be used, */ 00011 /* modified, and distributed under the terms of the FreeType project */ 00012 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 00013 /* this file you indicate that you have read the license and */ 00014 /* understand and accept it fully. */ 00015 /* */ 00016 /***************************************************************************/ 00017 00018 00019 #ifndef _FT_GASP_H_ 00020 #define _FT_GASP_H_ 00021 00022 #include <ft2build.h> 00023 #include FT_FREETYPE_H 00024 00025 #ifdef FREETYPE_H 00026 #error "freetype.h of FreeType 1 has been loaded!" 00027 #error "Please fix the directory search order for header files" 00028 #error "so that freetype.h of FreeType 2 is found first." 00029 #endif 00030 00031 00032 /*************************************************************************** 00033 * 00034 * @section: 00035 * gasp_table 00036 * 00037 * @title: 00038 * Gasp Table 00039 * 00040 * @abstract: 00041 * Retrieving TrueType `gasp' table entries. 00042 * 00043 * @description: 00044 * The function @FT_Get_Gasp can be used to query a TrueType or OpenType 00045 * font for specific entries in its `gasp' table, if any. This is 00046 * mainly useful when implementing native TrueType hinting with the 00047 * bytecode interpreter to duplicate the Windows text rendering results. 00048 */ 00049 00050 /************************************************************************* 00051 * 00052 * @enum: 00053 * FT_GASP_XXX 00054 * 00055 * @description: 00056 * A list of values and/or bit-flags returned by the @FT_Get_Gasp 00057 * function. 00058 * 00059 * @values: 00060 * FT_GASP_NO_TABLE :: 00061 * This special value means that there is no GASP table in this face. 00062 * It is up to the client to decide what to do. 00063 * 00064 * FT_GASP_DO_GRIDFIT :: 00065 * Grid-fitting and hinting should be performed at the specified ppem. 00066 * This *really* means TrueType bytecode interpretation. 00067 * 00068 * FT_GASP_DO_GRAY :: 00069 * Anti-aliased rendering should be performed at the specified ppem. 00070 * 00071 * FT_GASP_SYMMETRIC_SMOOTHING :: 00072 * Smoothing along multiple axes must be used with ClearType. 00073 * 00074 * FT_GASP_SYMMETRIC_GRIDFIT :: 00075 * Grid-fitting must be used with ClearType's symmetric smoothing. 00076 * 00077 * @note: 00078 * `ClearType' is Microsoft's implementation of LCD rendering, partly 00079 * protected by patents. 00080 * 00081 * @since: 00082 * 2.3.0 00083 */ 00084 #define FT_GASP_NO_TABLE -1 00085 #define FT_GASP_DO_GRIDFIT 0x01 00086 #define FT_GASP_DO_GRAY 0x02 00087 #define FT_GASP_SYMMETRIC_SMOOTHING 0x08 00088 #define FT_GASP_SYMMETRIC_GRIDFIT 0x10 00089 00090 00091 /************************************************************************* 00092 * 00093 * @func: 00094 * FT_Get_Gasp 00095 * 00096 * @description: 00097 * Read the `gasp' table from a TrueType or OpenType font file and 00098 * return the entry corresponding to a given character pixel size. 00099 * 00100 * @input: 00101 * face :: The source face handle. 00102 * ppem :: The vertical character pixel size. 00103 * 00104 * @return: 00105 * Bit flags (see @FT_GASP_XXX), or @FT_GASP_NO_TABLE if there is no 00106 * `gasp' table in the face. 00107 * 00108 * @since: 00109 * 2.3.0 00110 */ 00111 FT_EXPORT( FT_Int ) 00112 FT_Get_Gasp( FT_Face face, 00113 FT_UInt ppem ); 00114 00115 /* */ 00116 00117 #endif /* _FT_GASP_H_ */ 00118 00119 00120 /* END */
1.5.1