lib/3rdparty/freetype/src/autofit/afhints.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  afhints.h                                                              */
   4 /*                                                                         */
   5 /*    Auto-fitter hinting routines (specification).                        */
   6 /*                                                                         */
   7 /*  Copyright 2003, 2004, 2005, 2006, 2007, 2008 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 __AFHINTS_H__
  20 #define __AFHINTS_H__
  21
  22 #include "aftypes.h"
  23
  24 #define xxAF_SORT_SEGMENTS
  25
  26 FT_BEGIN_HEADER
  27
  28  /*
  29   *  The definition of outline glyph hints.  These are shared by all
  30   *  script analysis routines (until now).
  31   */
  32
  33   typedef enum  AF_Dimension_
  34   {
  35     AF_DIMENSION_HORZ = 0,  /* x coordinates,                    */
  36                             /* i.e., vertical segments & edges   */
  37     AF_DIMENSION_VERT = 1,  /* y coordinates,                    */
  38                             /* i.e., horizontal segments & edges */
  39
  40     AF_DIMENSION_MAX  /* do not remove */
  41
  42   } AF_Dimension;
  43
  44
  45   /* hint directions -- the values are computed so that two vectors are */
  46   /* in opposite directions iff `dir1 + dir2 == 0'                      */
  47   typedef enum  AF_Direction_
  48   {
  49     AF_DIR_NONE  =  4,
  50     AF_DIR_RIGHT =  1,
  51     AF_DIR_LEFT  = -1,
  52     AF_DIR_UP    =  2,
  53     AF_DIR_DOWN  = -2
  54
  55   } AF_Direction;
  56
  57
  58   /* point hint flags */
  59   typedef enum  AF_Flags_
  60   {
  61     AF_FLAG_NONE = 0,
  62
  63     /* point type flags */
  64     AF_FLAG_CONIC   = 1 << 0,
  65     AF_FLAG_CUBIC   = 1 << 1,
  66     AF_FLAG_CONTROL = AF_FLAG_CONIC | AF_FLAG_CUBIC,
  67
  68     /* point extremum flags */
  69     AF_FLAG_EXTREMA_X = 1 << 2,
  70     AF_FLAG_EXTREMA_Y = 1 << 3,
  71
  72     /* point roundness flags */
  73     AF_FLAG_ROUND_X = 1 << 4,
  74     AF_FLAG_ROUND_Y = 1 << 5,
  75
  76     /* point touch flags */
  77     AF_FLAG_TOUCH_X = 1 << 6,
  78     AF_FLAG_TOUCH_Y = 1 << 7,
  79
  80     /* candidates for weak interpolation have this flag set */
  81     AF_FLAG_WEAK_INTERPOLATION = 1 << 8,
  82
  83     /* all inflection points in the outline have this flag set */
  84     AF_FLAG_INFLECTION = 1 << 9
  85
  86   } AF_Flags;
  87
  88
  89   /* edge hint flags */
  90   typedef enum  AF_Edge_Flags_
  91   {
  92     AF_EDGE_NORMAL = 0,
  93     AF_EDGE_ROUND  = 1 << 0,
  94     AF_EDGE_SERIF  = 1 << 1,
  95     AF_EDGE_DONE   = 1 << 2
  96
  97   } AF_Edge_Flags;
  98
  99
 100   typedef struct AF_PointRec_*    AF_Point;
 101   typedef struct AF_SegmentRec_*  AF_Segment;
 102   typedef struct AF_EdgeRec_*     AF_Edge;
 103
 104
 105   typedef struct  AF_PointRec_
 106   {
 107     FT_UShort  flags;    /* point flags used by hinter   */
 108     FT_Char    in_dir;   /* direction of inwards vector  */
 109     FT_Char    out_dir;  /* direction of outwards vector */
 110
 111     FT_Pos     ox, oy;   /* original, scaled position                   */
 112     FT_Short   fx, fy;   /* original, unscaled position (font units)    */
 113     FT_Pos     x, y;     /* current position                            */
 114     FT_Pos     u, v;     /* current (x,y) or (y,x) depending on context */
 115
 116     AF_Point   next;     /* next point in contour     */
 117     AF_Point   prev;     /* previous point in contour */
 118
 119   } AF_PointRec;
 120
 121
 122   typedef struct  AF_SegmentRec_
 123   {
 124     FT_Byte     flags;       /* edge/segment flags for this segment */
 125     FT_Char     dir;         /* segment direction                   */
 126     FT_Short    pos;         /* position of segment                 */
 127     FT_Short    min_coord;   /* minimum coordinate of segment       */
 128     FT_Short    max_coord;   /* maximum coordinate of segment       */
 129     FT_Short    height;      /* the hinted segment height           */
 130
 131     AF_Edge     edge;        /* the segment's parent edge           */
 132     AF_Segment  edge_next;   /* link to next segment in parent edge */
 133
 134     AF_Segment  link;        /* (stem) link segment        */
 135     AF_Segment  serif;       /* primary segment for serifs */
 136     FT_Pos      num_linked;  /* number of linked segments  */
 137     FT_Pos      score;       /* used during stem matching  */
 138     FT_Pos      len;         /* used during stem matching  */
 139
 140     AF_Point    first;       /* first point in edge segment             */
 141     AF_Point    last;        /* last point in edge segment              */
 142     AF_Point*   contour;     /* ptr to first point of segment's contour */
 143
 144   } AF_SegmentRec;
 145
 146
 147   typedef struct  AF_EdgeRec_
 148   {
 149     FT_Short    fpos;       /* original, unscaled position (font units) */
 150     FT_Pos      opos;       /* original, scaled position                */
 151     FT_Pos      pos;        /* current position                         */
 152
 153     FT_Byte     flags;      /* edge flags                                   */
 154     FT_Char     dir;        /* edge direction                               */
 155     FT_Fixed    scale;      /* used to speed up interpolation between edges */
 156     AF_Width    blue_edge;  /* non-NULL if this is a blue edge              */
 157
 158     AF_Edge     link;
 159     AF_Edge     serif;
 160     FT_Short    num_linked;
 161
 162     FT_Int      score;
 163
 164     AF_Segment  first;
 165     AF_Segment  last;
 166
 167   } AF_EdgeRec;
 168
 169
 170   typedef struct  AF_AxisHintsRec_
 171   {
 172     FT_Int        num_segments;
 173     FT_Int        max_segments;
 174     AF_Segment    segments;
 175 #ifdef AF_SORT_SEGMENTS
 176     FT_Int        mid_segments;
 177 #endif
 178
 179     FT_Int        num_edges;
 180     FT_Int        max_edges;
 181     AF_Edge       edges;
 182
 183     AF_Direction  major_dir;
 184
 185   } AF_AxisHintsRec, *AF_AxisHints;
 186
 187
 188   typedef struct  AF_GlyphHintsRec_
 189   {
 190     FT_Memory         memory;
 191
 192     FT_Fixed          x_scale;
 193     FT_Pos            x_delta;
 194
 195     FT_Fixed          y_scale;
 196     FT_Pos            y_delta;
 197
 198     FT_Pos            edge_distance_threshold;
 199
 200     FT_Int            max_points;
 201     FT_Int            num_points;
 202     AF_Point          points;
 203
 204     FT_Int            max_contours;
 205     FT_Int            num_contours;
 206     AF_Point*         contours;
 207
 208     AF_AxisHintsRec   axis[AF_DIMENSION_MAX];
 209
 210     FT_UInt32         scaler_flags;  /* copy of scaler flags     */
 211     FT_UInt32         other_flags;   /* free for script-specific */
 212                                      /* implementations          */
 213     AF_ScriptMetrics  metrics;
 214
 215     FT_Pos            xmin_delta;    /* used for warping */
 216     FT_Pos            xmax_delta;
 217
 218   } AF_GlyphHintsRec;
 219
 220
 221 #define AF_HINTS_TEST_SCALER( h, f )  ( (h)->scaler_flags & (f) )
 222 #define AF_HINTS_TEST_OTHER( h, f )   ( (h)->other_flags  & (f) )
 223
 224
 225 #ifdef AF_DEBUG
 226
 227 #define AF_HINTS_DO_HORIZONTAL( h )                                     \
 228           ( !_af_debug_disable_horz_hints                            && \
 229             !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_HORIZONTAL ) )
 230
 231 #define AF_HINTS_DO_VERTICAL( h )                                     \
 232           ( !_af_debug_disable_vert_hints                          && \
 233             !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_VERTICAL ) )
 234
 235 #define AF_HINTS_DO_ADVANCE( h )                                \
 236           !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_ADVANCE )
 237
 238 #define AF_HINTS_DO_BLUES( h )  ( !_af_debug_disable_blue_hints )
 239
 240 #else /* !AF_DEBUG */
 241
 242 #define AF_HINTS_DO_HORIZONTAL( h )                                \
 243           !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_HORIZONTAL )
 244
 245 #define AF_HINTS_DO_VERTICAL( h )                                \
 246           !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_VERTICAL )
 247
 248 #define AF_HINTS_DO_ADVANCE( h )                                \
 249           !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_ADVANCE )
 250
 251 #define AF_HINTS_DO_BLUES( h )  1
 252
 253 #endif /* !AF_DEBUG */
 254
 255
 256   FT_LOCAL( AF_Direction )
 257   af_direction_compute( FT_Pos  dx,
 258                         FT_Pos  dy );
 259
 260
 261   FT_LOCAL( FT_Error )
 262   af_axis_hints_new_segment( AF_AxisHints  axis,
 263                              FT_Memory     memory,
 264                              AF_Segment   *asegment );
 265
 266   FT_LOCAL( FT_Error)
 267   af_axis_hints_new_edge( AF_AxisHints  axis,
 268                           FT_Int        fpos,
 269                           AF_Direction  dir,
 270                           FT_Memory     memory,
 271                           AF_Edge      *edge );
 272
 273   FT_LOCAL( void )
 274   af_glyph_hints_init( AF_GlyphHints  hints,
 275                        FT_Memory      memory );
 276
 277
 278
 279   /*
 280    *  recompute all AF_Point in a AF_GlyphHints from the definitions
 281    *  in a source outline
 282    */
 283   FT_LOCAL( void )
 284   af_glyph_hints_rescale( AF_GlyphHints     hints,
 285                           AF_ScriptMetrics  metrics );
 286
 287   FT_LOCAL( FT_Error )
 288   af_glyph_hints_reload( AF_GlyphHints  hints,
 289                          FT_Outline*    outline,
 290                          FT_Bool        get_inflections );
 291
 292   FT_LOCAL( void )
 293   af_glyph_hints_save( AF_GlyphHints  hints,
 294                        FT_Outline*    outline );
 295
 296   FT_LOCAL( void )
 297   af_glyph_hints_align_edge_points( AF_GlyphHints  hints,
 298                                     AF_Dimension   dim );
 299
 300   FT_LOCAL( void )
 301   af_glyph_hints_align_strong_points( AF_GlyphHints  hints,
 302                                       AF_Dimension   dim );
 303
 304   FT_LOCAL( void )
 305   af_glyph_hints_align_weak_points( AF_GlyphHints  hints,
 306                                     AF_Dimension   dim );
 307
 308 #ifdef AF_USE_WARPER
 309   FT_LOCAL( void )
 310   af_glyph_hints_scale_dim( AF_GlyphHints  hints,
 311                             AF_Dimension   dim,
 312                             FT_Fixed       scale,
 313                             FT_Pos         delta );
 314 #endif
 315
 316   FT_LOCAL( void )
 317   af_glyph_hints_done( AF_GlyphHints  hints );
 318
 319 /* */
 320
 321 #define AF_SEGMENT_LEN( seg )          ( (seg)->max_coord - (seg)->min_coord )
 322
 323 #define AF_SEGMENT_DIST( seg1, seg2 )  ( ( (seg1)->pos > (seg2)->pos )   \
 324                                            ? (seg1)->pos - (seg2)->pos   \
 325                                            : (seg2)->pos - (seg1)->pos )
 326
 327
 328 FT_END_HEADER
 329
 330 #endif /* __AFHINTS_H__ */
 331
 332
 333 /* END */