modules/freetype2/src/autofit/aflatin.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  aflatin.h                                                              */
   4 /*                                                                         */
   5 /*    Auto-fitter hinting routines for latin script (specification).       */
   6 /*                                                                         */
   7 /*  Copyright 2003, 2004, 2005, 2006, 2007 by                              */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19 #ifndef __AFLATIN_H__
  20 #define __AFLATIN_H__
  21
  22 #include "afhints.h"
  23
  24
  25 FT_BEGIN_HEADER
  26
  27
  28   /* the latin-specific script class */
  29
  30   FT_CALLBACK_TABLE const AF_ScriptClassRec
  31   af_latin_script_class;
  32
  33
  34 /* constants are given with units_per_em == 2048 in mind */
  35 #define AF_LATIN_CONSTANT( metrics, c ) \
  36   ( ( (c) * (FT_Long)( (AF_LatinMetrics)(metrics) )->units_per_em ) / 2048 )
  37
  38
  39   /*************************************************************************/
  40   /*************************************************************************/
  41   /*****                                                               *****/
  42   /*****            L A T I N   G L O B A L   M E T R I C S            *****/
  43   /*****                                                               *****/
  44   /*************************************************************************/
  45   /*************************************************************************/
  46
  47
  48   /*
  49    *  The following declarations could be embedded in the file `aflatin.c';
  50    *  they have been made semi-public to allow alternate script hinters to
  51    *  re-use some of them.
  52    */
  53
  54
  55   /* Latin (global) metrics management */
  56
  57   enum
  58   {
  59     AF_LATIN_BLUE_CAPITAL_TOP,
  60     AF_LATIN_BLUE_CAPITAL_BOTTOM,
  61     AF_LATIN_BLUE_SMALL_F_TOP,
  62     AF_LATIN_BLUE_SMALL_TOP,
  63     AF_LATIN_BLUE_SMALL_BOTTOM,
  64     AF_LATIN_BLUE_SMALL_MINOR,
  65
  66     AF_LATIN_BLUE_MAX
  67   };
  68
  69
  70 #define AF_LATIN_IS_TOP_BLUE( b )  ( (b) == AF_LATIN_BLUE_CAPITAL_TOP || \
  71                                      (b) == AF_LATIN_BLUE_SMALL_F_TOP || \
  72                                      (b) == AF_LATIN_BLUE_SMALL_TOP   )
  73
  74 #define AF_LATIN_MAX_WIDTHS  16
  75 #define AF_LATIN_MAX_BLUES   AF_LATIN_BLUE_MAX
  76
  77
  78   enum
  79   {
  80     AF_LATIN_BLUE_ACTIVE     = 1 << 0,
  81     AF_LATIN_BLUE_TOP        = 1 << 1,
  82     AF_LATIN_BLUE_ADJUSTMENT = 1 << 2,  /* used for scale adjustment */
  83                                         /* optimization              */
  84     AF_LATIN_BLUE_FLAG_MAX
  85   };
  86
  87
  88   typedef struct  AF_LatinBlueRec_
  89   {
  90     AF_WidthRec  ref;
  91     AF_WidthRec  shoot;
  92     FT_UInt      flags;
  93
  94   } AF_LatinBlueRec, *AF_LatinBlue;
  95
  96
  97   typedef struct  AF_LatinAxisRec_
  98   {
  99     FT_Fixed         scale;
 100     FT_Pos           delta;
 101
 102     FT_UInt          width_count;
 103     AF_WidthRec      widths[AF_LATIN_MAX_WIDTHS];
 104     FT_Pos           edge_distance_threshold;
 105     FT_Pos           standard_width;
 106     FT_Bool          extra_light;
 107
 108     /* ignored for horizontal metrics */
 109     FT_Bool          control_overshoot;
 110     FT_UInt          blue_count;
 111     AF_LatinBlueRec  blues[AF_LATIN_BLUE_MAX];
 112
 113     FT_Fixed         org_scale;
 114     FT_Pos           org_delta;
 115
 116   } AF_LatinAxisRec, *AF_LatinAxis;
 117
 118
 119   typedef struct  AF_LatinMetricsRec_
 120   {
 121     AF_ScriptMetricsRec  root;
 122     FT_UInt              units_per_em;
 123     AF_LatinAxisRec      axis[AF_DIMENSION_MAX];
 124
 125   } AF_LatinMetricsRec, *AF_LatinMetrics;
 126
 127
 128   FT_LOCAL( FT_Error )
 129   af_latin_metrics_init( AF_LatinMetrics  metrics,
 130                          FT_Face          face );
 131
 132   FT_LOCAL( void )
 133   af_latin_metrics_scale( AF_LatinMetrics  metrics,
 134                           AF_Scaler        scaler );
 135
 136   FT_LOCAL( void )
 137   af_latin_metrics_init_widths( AF_LatinMetrics  metrics,
 138                                 FT_Face          face,
 139                                 FT_ULong         charcode );
 140
 141
 142   /*************************************************************************/
 143   /*************************************************************************/
 144   /*****                                                               *****/
 145   /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
 146   /*****                                                               *****/
 147   /*************************************************************************/
 148   /*************************************************************************/
 149
 150   enum
 151   {
 152     AF_LATIN_HINTS_HORZ_SNAP   = 1 << 0, /* enable stem width snapping  */
 153     AF_LATIN_HINTS_VERT_SNAP   = 1 << 1, /* enable stem height snapping */
 154     AF_LATIN_HINTS_STEM_ADJUST = 1 << 2, /* enable stem width/height    */
 155                                          /* adjustment                  */
 156     AF_LATIN_HINTS_MONO        = 1 << 3  /* indicate monochrome         */
 157                                          /* rendering                   */
 158   };
 159
 160
 161 #define AF_LATIN_HINTS_DO_HORZ_SNAP( h )             \
 162   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )
 163
 164 #define AF_LATIN_HINTS_DO_VERT_SNAP( h )             \
 165   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )
 166
 167 #define AF_LATIN_HINTS_DO_STEM_ADJUST( h )             \
 168   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )
 169
 170 #define AF_LATIN_HINTS_DO_MONO( h )             \
 171   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )
 172
 173
 174   /*
 175    *  This shouldn't normally be exported.  However, other scripts might
 176    *  like to use this function as-is.
 177    */
 178   FT_LOCAL( FT_Error )
 179   af_latin_hints_compute_segments( AF_GlyphHints  hints,
 180                                    AF_Dimension   dim );
 181
 182   /*
 183    *  This shouldn't normally be exported.  However, other scripts might
 184    *  want to use this function as-is.
 185    */
 186   FT_LOCAL( void )
 187   af_latin_hints_link_segments( AF_GlyphHints  hints,
 188                                 AF_Dimension   dim );
 189
 190   /*
 191    *  This shouldn't normally be exported.  However, other scripts might
 192    *  want to use this function as-is.
 193    */
 194   FT_LOCAL( FT_Error )
 195   af_latin_hints_compute_edges( AF_GlyphHints  hints,
 196                                 AF_Dimension   dim );
 197
 198   FT_LOCAL( FT_Error )
 199   af_latin_hints_detect_features( AF_GlyphHints  hints,
 200                                   AF_Dimension   dim );
 201
 202 /* */
 203
 204 FT_END_HEADER
 205
 206 #endif /* __AFLATIN_H__ */
 207
 208
 209 /* END */