1/***************************************************************************/
2/*                                                                         */
3/*  aflatin.h                                                              */
4/*                                                                         */
5/*    Auto-fitter hinting routines for latin script (specification).       */
6/*                                                                         */
7/*  Copyright 2003-2007, 2009, 2011-2012 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
25FT_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
138  FT_LOCAL( void )
139  af_latin_metrics_check_digits( AF_LatinMetrics  metrics,
140                                 FT_Face          face );
141
142
143  /*************************************************************************/
144  /*************************************************************************/
145  /*****                                                               *****/
146  /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
147  /*****                                                               *****/
148  /*************************************************************************/
149  /*************************************************************************/
150
151  enum
152  {
153    AF_LATIN_HINTS_HORZ_SNAP   = 1 << 0, /* enable stem width snapping  */
154    AF_LATIN_HINTS_VERT_SNAP   = 1 << 1, /* enable stem height snapping */
155    AF_LATIN_HINTS_STEM_ADJUST = 1 << 2, /* enable stem width/height    */
156                                         /* adjustment                  */
157    AF_LATIN_HINTS_MONO        = 1 << 3  /* indicate monochrome         */
158                                         /* rendering                   */
159  };
160
161
162#define AF_LATIN_HINTS_DO_HORZ_SNAP( h )             \
163  AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )
164
165#define AF_LATIN_HINTS_DO_VERT_SNAP( h )             \
166  AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )
167
168#define AF_LATIN_HINTS_DO_STEM_ADJUST( h )             \
169  AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )
170
171#define AF_LATIN_HINTS_DO_MONO( h )             \
172  AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )
173
174
175  /*
176   *  The next functions shouldn't normally be exported.  However, other
177   *  scripts might like to use these functions as-is.
178   */
179  FT_LOCAL( FT_Error )
180  af_latin_hints_compute_segments( AF_GlyphHints  hints,
181                                   AF_Dimension   dim );
182
183  FT_LOCAL( void )
184  af_latin_hints_link_segments( AF_GlyphHints  hints,
185                                AF_Dimension   dim );
186
187  FT_LOCAL( FT_Error )
188  af_latin_hints_compute_edges( AF_GlyphHints  hints,
189                                AF_Dimension   dim );
190
191  FT_LOCAL( FT_Error )
192  af_latin_hints_detect_features( AF_GlyphHints  hints,
193                                  AF_Dimension   dim );
194
195/* */
196
197FT_END_HEADER
198
199#endif /* __AFLATIN_H__ */
200
201
202/* END */
203