third_party/harfbuzz/src/harfbuzz-gpos.h

   1 /*
   2  * Copyright (C) 1998-2004  David Turner and Werner Lemberg
   3  * Copyright (C) 2006  Behdad Esfahbod
   4  *
   5  * This is part of HarfBuzz, an OpenType Layout engine library.
   6  *
   7  * Permission is hereby granted, without written agreement and without
   8  * license or royalty fees, to use, copy, modify, and distribute this
   9  * software and its documentation for any purpose, provided that the
  10  * above copyright notice and the following two paragraphs appear in
  11  * all copies of this software.
  12  *
  13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  17  * DAMAGE.
  18  *
  19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  24  */
  25
  26 #ifndef HARFBUZZ_GPOS_H
  27 #define HARFBUZZ_GPOS_H
  28
  29 #include "harfbuzz-gdef.h"
  30 #include "harfbuzz-buffer.h"
  31
  32 HB_BEGIN_HEADER
  33
  34
  35 /* Lookup types for glyph positioning */
  36
  37 #define HB_GPOS_LOOKUP_SINGLE     1
  38 #define HB_GPOS_LOOKUP_PAIR       2
  39 #define HB_GPOS_LOOKUP_CURSIVE    3
  40 #define HB_GPOS_LOOKUP_MARKBASE   4
  41 #define HB_GPOS_LOOKUP_MARKLIG    5
  42 #define HB_GPOS_LOOKUP_MARKMARK   6
  43 #define HB_GPOS_LOOKUP_CONTEXT    7
  44 #define HB_GPOS_LOOKUP_CHAIN      8
  45 #define HB_GPOS_LOOKUP_EXTENSION  9
  46
  47 #ifdef HB_SUPPORT_MULTIPLE_MASTER
  48 /* A pointer to a function which accesses the PostScript interpreter.
  49    Multiple Master fonts need this interface to convert a metric ID
  50    (as stored in an OpenType font version 1.2 or higher) `metric_id'
  51    into a metric value (returned in `metric_value').
  52
  53    `data' points to the user-defined structure specified during a
  54    call to HB_GPOS_Register_MM_Function().
  55
  56    `metric_value' must be returned as a scaled value (but shouldn't
  57    be rounded).                                                       */
  58
  59 typedef HB_Error  (*HB_MMFunction)(HB_Font       font,
  60                                     HB_UShort    metric_id,
  61                                     HB_Fixed*      metric_value,
  62                                     void*        data );
  63 #endif
  64
  65
  66 struct  HB_GPOSHeader_
  67 {
  68   HB_16Dot16           Version;
  69
  70   HB_ScriptList     ScriptList;
  71   HB_FeatureList    FeatureList;
  72   HB_LookupList     LookupList;
  73
  74   HB_GDEFHeader*    gdef;
  75
  76 #ifdef HB_SUPPORT_MULTIPLE_MASTER
  77   /* this is OpenType 1.2 -- Multiple Master fonts need this
  78      callback function to get various metric values from the
  79      PostScript interpreter.                                 */
  80
  81   HB_MMFunction     mmfunc;
  82   void*              data;
  83 #endif
  84 };
  85
  86 typedef struct HB_GPOSHeader_  HB_GPOSHeader;
  87 typedef HB_GPOSHeader* HB_GPOS;
  88
  89
  90 HB_Error  HB_Load_GPOS_Table( HB_Stream stream,
  91                               HB_GPOSHeader** gpos,
  92                               HB_GDEFHeader*  gdef,
  93                               HB_Stream       gdefStream );
  94
  95
  96 HB_Error  HB_Done_GPOS_Table( HB_GPOSHeader* gpos );
  97
  98
  99 HB_Error  HB_GPOS_Select_Script( HB_GPOSHeader*  gpos,
 100                                  HB_UInt         script_tag,
 101                                  HB_UShort*       script_index );
 102
 103 HB_Error  HB_GPOS_Select_Language( HB_GPOSHeader*  gpos,
 104                                    HB_UInt         language_tag,
 105                                    HB_UShort        script_index,
 106                                    HB_UShort*       language_index,
 107                                    HB_UShort*       req_feature_index );
 108
 109 HB_Error  HB_GPOS_Select_Feature( HB_GPOSHeader*  gpos,
 110                                   HB_UInt         feature_tag,
 111                                   HB_UShort        script_index,
 112                                   HB_UShort        language_index,
 113                                   HB_UShort*       feature_index );
 114
 115
 116 HB_Error  HB_GPOS_Query_Scripts( HB_GPOSHeader*  gpos,
 117                                  HB_UInt**       script_tag_list );
 118
 119 HB_Error  HB_GPOS_Query_Languages( HB_GPOSHeader*  gpos,
 120                                    HB_UShort        script_index,
 121                                    HB_UInt**       language_tag_list );
 122
 123 HB_Error  HB_GPOS_Query_Features( HB_GPOSHeader*  gpos,
 124                                   HB_UShort        script_index,
 125                                   HB_UShort        language_index,
 126                                   HB_UInt**       feature_tag_list );
 127
 128
 129 HB_Error  HB_GPOS_Add_Feature( HB_GPOSHeader*  gpos,
 130                                HB_UShort        feature_index,
 131                                HB_UInt          property );
 132
 133 HB_Error  HB_GPOS_Clear_Features( HB_GPOSHeader*  gpos );
 134
 135
 136 #ifdef HB_SUPPORT_MULTIPLE_MASTER
 137 HB_Error  HB_GPOS_Register_MM_Function( HB_GPOSHeader*  gpos,
 138                                         HB_MMFunction   mmfunc,
 139                                         void*            data );
 140 #endif
 141
 142 /* If `dvi' is TRUE, glyph contour points for anchor points and device
 143    tables are ignored -- you will get device independent values.         */
 144
 145
 146 HB_Error  HB_GPOS_Apply_String( HB_Font           font,
 147                                 HB_GPOSHeader*   gpos,
 148                                 HB_UShort         load_flags,
 149                                 HB_Buffer        buffer,
 150                                 HB_Bool           dvi,
 151                                 HB_Bool           r2l );
 152
 153 HB_END_HEADER
 154
 155 #endif /* HARFBUZZ_GPOS_H */