lib/talatin.h

   1 /* talatin.h */
   2
   3 /*
   4  * Copyright (C) 2011-2014 by Werner Lemberg.
   5  *
   6  * This file is part of the ttfautohint library, and may only be used,
   7  * modified, and distributed under the terms given in `COPYING'.  By
   8  * continuing to use, modify, or distribute this file you indicate that you
   9  * have read `COPYING' and understand and accept it fully.
  10  *
  11  * The file `COPYING' mentioned in the previous paragraph is distributed
  12  * with the ttfautohint library.
  13  */
  14
  15
  16 /* originally file `aflatin.h' (2011-Mar-28) from FreeType */
  17
  18 /* heavily modified 2011 by Werner Lemberg <wl@gnu.org> */
  19
  20 #ifndef __TALATIN_H__
  21 #define __TALATIN_H__
  22
  23 #include "tatypes.h"
  24 #include "tahints.h"
  25
  26
  27 /* the `latin' writing system */
  28
  29 extern const TA_WritingSystemClassRec ta_latin_writing_system_class;
  30
  31 /* the latin-specific script classes */
  32
  33 extern const TA_ScriptClassRec ta_cyrl_script_class;
  34 extern const TA_ScriptClassRec ta_grek_script_class;
  35 extern const TA_ScriptClassRec ta_hebr_script_class;
  36 extern const TA_ScriptClassRec ta_latn_script_class;
  37 #if 0
  38 extern const TA_ScriptClassRec ta_armn_script_class;
  39 #endif
  40
  41
  42 /* constants are given with units_per_em == 2048 in mind */
  43 #define TA_LATIN_CONSTANT(metrics, c) \
  44           (((c) * (FT_Long)((TA_LatinMetrics)(metrics))->units_per_em) / 2048)
  45
  46
  47 /* Latin (global) metrics management */
  48
  49 #define TA_LATIN_IS_TOP_BLUE(b) \
  50           ((b)->properties & TA_BLUE_PROPERTY_LATIN_TOP)
  51 #define TA_LATIN_IS_X_HEIGHT_BLUE(b) \
  52           ((b)->properties & TA_BLUE_PROPERTY_LATIN_X_HEIGHT)
  53 #define TA_LATIN_IS_LONG_BLUE(b) \
  54           ((b)->properties &TA_BLUE_PROPERTY_LATIN_LONG)
  55
  56 #define TA_LATIN_MAX_WIDTHS 16
  57
  58
  59 #define TA_LATIN_BLUE_ACTIVE  (1 << 0) /* set if zone height is <= 3/4px */
  60 #define TA_LATIN_BLUE_TOP (1 << 1) /* result of TA_LATIN_IS_TOP_BLUE */
  61 #define TA_LATIN_BLUE_ADJUSTMENT (1 << 2) /* used for scale adjustment */
  62                                           /* optimization */
  63
  64
  65 typedef struct TA_LatinBlueRec_
  66 {
  67   TA_WidthRec ref;
  68   TA_WidthRec shoot;
  69   FT_UInt flags;
  70 } TA_LatinBlueRec, *TA_LatinBlue;
  71
  72
  73 typedef struct TA_LatinAxisRec_
  74 {
  75   FT_Fixed scale;
  76   FT_Pos delta;
  77
  78   FT_UInt width_count; /* number of used widths */
  79   TA_WidthRec widths[TA_LATIN_MAX_WIDTHS]; /* widths array */
  80   FT_Pos edge_distance_threshold; /* used for creating edges */
  81   FT_Pos standard_width; /* the default stem thickness */
  82   FT_Bool extra_light; /* is standard width very light? */
  83
  84   /* ignored for horizontal metrics */
  85   FT_UInt blue_count;
  86   /* we add two blue zones for usWinAscent and usWinDescent */
  87   TA_LatinBlueRec blues[TA_BLUE_STRINGSET_MAX + 2];
  88
  89   FT_Fixed org_scale;
  90   FT_Pos org_delta;
  91 } TA_LatinAxisRec, *TA_LatinAxis;
  92
  93
  94 typedef struct TA_LatinMetricsRec_
  95 {
  96   TA_StyleMetricsRec root;
  97   FT_UInt units_per_em;
  98   TA_LatinAxisRec axis[TA_DIMENSION_MAX];
  99 } TA_LatinMetricsRec, *TA_LatinMetrics;
 100
 101
 102 FT_Error
 103 ta_latin_metrics_init(TA_LatinMetrics metrics,
 104                       FT_Face face);
 105
 106 void
 107 ta_latin_metrics_scale(TA_LatinMetrics metrics,
 108                        TA_Scaler scaler);
 109
 110 void
 111 ta_latin_metrics_init_widths(TA_LatinMetrics metrics,
 112                              FT_Face face);
 113
 114 void
 115 ta_latin_metrics_check_digits(TA_LatinMetrics metrics,
 116                               FT_Face face);
 117
 118
 119 #define TA_LATIN_HINTS_HORZ_SNAP (1 << 0) /* enable stem width snapping */
 120 #define TA_LATIN_HINTS_VERT_SNAP (1 << 1) /* enable stem height snapping */
 121 #define TA_LATIN_HINTS_STEM_ADJUST (1 << 2) /* enable stem width/height */
 122                                             /* adjustment */
 123 #define TA_LATIN_HINTS_MONO (1 << 3) /* indicate monochrome rendering */
 124
 125
 126 #define TA_LATIN_HINTS_DO_HORZ_SNAP(h) \
 127           TA_HINTS_TEST_OTHER(h, TA_LATIN_HINTS_HORZ_SNAP)
 128 #define TA_LATIN_HINTS_DO_VERT_SNAP(h) \
 129           TA_HINTS_TEST_OTHER(h, TA_LATIN_HINTS_VERT_SNAP)
 130 #define TA_LATIN_HINTS_DO_STEM_ADJUST(h) \
 131           TA_HINTS_TEST_OTHER(h, TA_LATIN_HINTS_STEM_ADJUST)
 132 #define TA_LATIN_HINTS_DO_MONO(h) \
 133           TA_HINTS_TEST_OTHER(h, TA_LATIN_HINTS_MONO)
 134
 135
 136 /* the next functions shouldn't normally be exported; */
 137 /* however, other scripts might like to use these functions as-is */
 138
 139 FT_Error
 140 ta_latin_hints_compute_segments(TA_GlyphHints hints,
 141                                 TA_Dimension dim);
 142 void
 143 ta_latin_hints_link_segments(TA_GlyphHints hints,
 144                              TA_Dimension dim);
 145 FT_Error
 146 ta_latin_hints_compute_edges(TA_GlyphHints hints,
 147                              TA_Dimension dim);
 148 FT_Error
 149 ta_latin_hints_detect_features(TA_GlyphHints hints,
 150                                TA_Dimension dim);
 151
 152 #endif /* __TALATIN_H__ */
 153
 154 /* end of talatin.h */