src/autofit/aflatin.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  aflatin.h                                                              */
   4 /*                                                                         */
   5 /*    Auto-fitter hinting routines for latin script (specification).       */
   6 /*                                                                         */
   7 /*  Copyright 2003-2007, 2009, 2011 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   AF_DECLARE_SCRIPT_CLASS(af_latin_script_class)
  31
  32
  33   /* constants are given with units_per_em == 2048 in mind */
  34 #define AF_LATIN_CONSTANT( metrics, c )                                      \
  35   ( ( (c) * (FT_Long)( (AF_LatinMetrics)(metrics) )->units_per_em ) / 2048 )
  36
  37
  38   /*************************************************************************/
  39   /*************************************************************************/
  40   /*****                                                               *****/
  41   /*****            L A T I N   G L O B A L   M E T R I C S            *****/
  42   /*****                                                               *****/
  43   /*************************************************************************/
  44   /*************************************************************************/
  45
  46
  47   /*
  48    *  The following declarations could be embedded in the file `aflatin.c';
  49    *  they have been made semi-public to allow alternate script hinters to
  50    *  re-use some of them.
  51    */
  52
  53
  54   /* Latin (global) metrics management */
  55
  56   enum
  57   {
  58     AF_LATIN_BLUE_CAPITAL_TOP,
  59     AF_LATIN_BLUE_CAPITAL_BOTTOM,
  60     AF_LATIN_BLUE_SMALL_F_TOP,
  61     AF_LATIN_BLUE_SMALL_TOP,
  62     AF_LATIN_BLUE_SMALL_BOTTOM,
  63     AF_LATIN_BLUE_SMALL_MINOR,
  64
  65     AF_LATIN_BLUE_MAX
  66   };
  67
  68
  69 #define AF_LATIN_IS_TOP_BLUE( b )  ( (b) == AF_LATIN_BLUE_CAPITAL_TOP || \
  70                                      (b) == AF_LATIN_BLUE_SMALL_F_TOP || \
  71                                      (b) == AF_LATIN_BLUE_SMALL_TOP   )
  72
  73 #define AF_LATIN_MAX_WIDTHS  16
  74 #define AF_LATIN_MAX_BLUES   AF_LATIN_BLUE_MAX
  75
  76
  77   enum
  78   {
  79     AF_LATIN_BLUE_ACTIVE     = 1 << 0,  /* set if zone height is <= 3/4px */
  80     AF_LATIN_BLUE_TOP        = 1 << 1,  /* result of AF_LATIN_IS_TOP_BLUE */
  81     AF_LATIN_BLUE_ADJUSTMENT = 1 << 2,  /* used for scale adjustment      */
  82                                         /* optimization                   */
  83     AF_LATIN_BLUE_FLAG_MAX
  84   };
  85
  86
  87   typedef struct  AF_LatinBlueRec_
  88   {
  89     AF_WidthRec  ref;
  90     AF_WidthRec  shoot;
  91     FT_UInt      flags;
  92
  93   } AF_LatinBlueRec, *AF_LatinBlue;
  94
  95
  96   typedef struct  AF_LatinAxisRec_
  97   {
  98     FT_Fixed         scale;
  99     FT_Pos           delta;
 100
 101     FT_UInt          width_count;                 /* number of used widths */
 102     AF_WidthRec      widths[AF_LATIN_MAX_WIDTHS]; /* widths array          */
 103     FT_Pos           edge_distance_threshold;   /* used for creating edges */
 104     FT_Pos           standard_width;         /* the default stem thickness */
 105     FT_Bool          extra_light;         /* is standard width very light? */
 106
 107     /* ignored for horizontal metrics */
 108     FT_UInt          blue_count;
 109     AF_LatinBlueRec  blues[AF_LATIN_BLUE_MAX];
 110
 111     FT_Fixed         org_scale;
 112     FT_Pos           org_delta;
 113
 114   } AF_LatinAxisRec, *AF_LatinAxis;
 115
 116
 117   typedef struct  AF_LatinMetricsRec_
 118   {
 119     AF_ScriptMetricsRec  root;
 120     FT_UInt              units_per_em;
 121     AF_LatinAxisRec      axis[AF_DIMENSION_MAX];
 122
 123   } AF_LatinMetricsRec, *AF_LatinMetrics;
 124
 125
 126   FT_LOCAL( FT_Error )
 127   af_latin_metrics_init( AF_LatinMetrics  metrics,
 128                          FT_Face          face );
 129
 130   FT_LOCAL( void )
 131   af_latin_metrics_scale( AF_LatinMetrics  metrics,
 132                           AF_Scaler        scaler );
 133
 134   FT_LOCAL( void )
 135   af_latin_metrics_init_widths( AF_LatinMetrics  metrics,
 136                                 FT_Face          face,
 137                                 FT_ULong         charcode );
 138
 139   FT_LOCAL( void )
 140   af_latin_metrics_check_digits( AF_LatinMetrics  metrics,
 141                                  FT_Face          face );
 142
 143
 144   /*************************************************************************/
 145   /*************************************************************************/
 146   /*****                                                               *****/
 147   /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
 148   /*****                                                               *****/
 149   /*************************************************************************/
 150   /*************************************************************************/
 151
 152   enum
 153   {
 154     AF_LATIN_HINTS_HORZ_SNAP   = 1 << 0, /* enable stem width snapping  */
 155     AF_LATIN_HINTS_VERT_SNAP   = 1 << 1, /* enable stem height snapping */
 156     AF_LATIN_HINTS_STEM_ADJUST = 1 << 2, /* enable stem width/height    */
 157                                          /* adjustment                  */
 158     AF_LATIN_HINTS_MONO        = 1 << 3  /* indicate monochrome         */
 159                                          /* rendering                   */
 160   };
 161
 162
 163 #define AF_LATIN_HINTS_DO_HORZ_SNAP( h )             \
 164   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )
 165
 166 #define AF_LATIN_HINTS_DO_VERT_SNAP( h )             \
 167   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )
 168
 169 #define AF_LATIN_HINTS_DO_STEM_ADJUST( h )             \
 170   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )
 171
 172 #define AF_LATIN_HINTS_DO_MONO( h )             \
 173   AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )
 174
 175
 176   /*
 177    *  This shouldn't normally be exported.  However, other scripts might
 178    *  like to use this function as-is.
 179    */
 180   FT_LOCAL( FT_Error )
 181   af_latin_hints_compute_segments( AF_GlyphHints  hints,
 182                                    AF_Dimension   dim );
 183
 184   /*
 185    *  This shouldn't normally be exported.  However, other scripts might
 186    *  want to use this function as-is.
 187    */
 188   FT_LOCAL( void )
 189   af_latin_hints_link_segments( AF_GlyphHints  hints,
 190                                 AF_Dimension   dim );
 191
 192   /*
 193    *  This shouldn't normally be exported.  However, other scripts might
 194    *  want to use this function as-is.
 195    */
 196   FT_LOCAL( FT_Error )
 197   af_latin_hints_compute_edges( AF_GlyphHints  hints,
 198                                 AF_Dimension   dim );
 199
 200   FT_LOCAL( FT_Error )
 201   af_latin_hints_detect_features( AF_GlyphHints  hints,
 202                                   AF_Dimension   dim );
 203
 204 /* */
 205
 206 FT_END_HEADER
 207
 208 #endif /* __AFLATIN_H__ */
 209
 210
 211 /* END */