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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  aflatin2.c                                                             */
      4 /*                                                                         */
      5 /*    Auto-fitter hinting routines for latin script (body).                */
      6 /*                                                                         */
      7 /*  Copyright 2003-2013 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 #include FT_ADVANCES_H
     20 
     21 #include "afglobal.h"
     22 #include "aflatin.h"
     23 #include "aflatin2.h"
     24 #include "aferrors.h"
     25 
     26 
     27 #ifdef AF_CONFIG_OPTION_USE_WARPER
     28 #include "afwarp.h"
     29 #endif
     30 
     31 
     32   /*************************************************************************/
     33   /*                                                                       */
     34   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
     35   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
     36   /* messages during execution.                                            */
     37   /*                                                                       */
     38 #undef  FT_COMPONENT
     39 #define FT_COMPONENT  trace_aflatin2
     40 
     41 
     42   FT_LOCAL_DEF( FT_Error )
     43   af_latin2_hints_compute_segments( AF_GlyphHints  hints,
     44                                     AF_Dimension   dim );
     45 
     46   FT_LOCAL_DEF( void )
     47   af_latin2_hints_link_segments( AF_GlyphHints  hints,
     48                                  AF_Dimension   dim );
     49 
     50   /*************************************************************************/
     51   /*************************************************************************/
     52   /*****                                                               *****/
     53   /*****            L A T I N   G L O B A L   M E T R I C S            *****/
     54   /*****                                                               *****/
     55   /*************************************************************************/
     56   /*************************************************************************/
     57 
     58   FT_LOCAL_DEF( void )
     59   af_latin2_metrics_init_widths( AF_LatinMetrics  metrics,
     60                                  FT_Face          face )
     61   {
     62     /* scan the array of segments in each direction */
     63     AF_GlyphHintsRec  hints[1];
     64 
     65 
     66     af_glyph_hints_init( hints, face->memory );
     67 
     68     metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
     69     metrics->axis[AF_DIMENSION_VERT].width_count = 0;
     70 
     71     {
     72       FT_Error             error;
     73       FT_UInt              glyph_index;
     74       int                  dim;
     75       AF_LatinMetricsRec   dummy[1];
     76       AF_Scaler            scaler = &dummy->root.scaler;
     77 
     78 
     79       glyph_index = FT_Get_Char_Index( face,
     80                                        metrics->root.clazz->standard_char );
     81       if ( glyph_index == 0 )
     82         goto Exit;
     83 
     84       error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
     85       if ( error || face->glyph->outline.n_points <= 0 )
     86         goto Exit;
     87 
     88       FT_ZERO( dummy );
     89 
     90       dummy->units_per_em = metrics->units_per_em;
     91       scaler->x_scale     = scaler->y_scale = 0x10000L;
     92       scaler->x_delta     = scaler->y_delta = 0;
     93       scaler->face        = face;
     94       scaler->render_mode = FT_RENDER_MODE_NORMAL;
     95       scaler->flags       = 0;
     96 
     97       af_glyph_hints_rescale( hints, (AF_ScriptMetrics)dummy );
     98 
     99       error = af_glyph_hints_reload( hints, &face->glyph->outline );
    100       if ( error )
    101         goto Exit;
    102 
    103       for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
    104       {
    105         AF_LatinAxis  axis    = &metrics->axis[dim];
    106         AF_AxisHints  axhints = &hints->axis[dim];
    107         AF_Segment    seg, limit, link;
    108         FT_UInt       num_widths = 0;
    109 
    110 
    111         error = af_latin2_hints_compute_segments( hints,
    112                                                  (AF_Dimension)dim );
    113         if ( error )
    114           goto Exit;
    115 
    116         af_latin2_hints_link_segments( hints,
    117                                       (AF_Dimension)dim );
    118 
    119         seg   = axhints->segments;
    120         limit = seg + axhints->num_segments;
    121 
    122         for ( ; seg < limit; seg++ )
    123         {
    124           link = seg->link;
    125 
    126           /* we only consider stem segments there! */
    127           if ( link && link->link == seg && link > seg )
    128           {
    129             FT_Pos  dist;
    130 
    131 
    132             dist = seg->pos - link->pos;
    133             if ( dist < 0 )
    134               dist = -dist;
    135 
    136             if ( num_widths < AF_LATIN_MAX_WIDTHS )
    137               axis->widths[num_widths++].org = dist;
    138           }
    139         }
    140 
    141         af_sort_widths( num_widths, axis->widths );
    142         axis->width_count = num_widths;
    143       }
    144 
    145   Exit:
    146       for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
    147       {
    148         AF_LatinAxis  axis = &metrics->axis[dim];
    149         FT_Pos        stdw;
    150 
    151 
    152         stdw = ( axis->width_count > 0 )
    153                  ? axis->widths[0].org
    154                  : AF_LATIN_CONSTANT( metrics, 50 );
    155 
    156         /* let's try 20% of the smallest width */
    157         axis->edge_distance_threshold = stdw / 5;
    158         axis->standard_width          = stdw;
    159         axis->extra_light             = 0;
    160       }
    161     }
    162 
    163     af_glyph_hints_done( hints );
    164   }
    165 
    166 
    167 
    168 #define AF_LATIN_MAX_TEST_CHARACTERS  12
    169 
    170 
    171   static const char af_latin2_blue_chars[AF_LATIN_MAX_BLUES]
    172                                         [AF_LATIN_MAX_TEST_CHARACTERS+1] =
    173   {
    174     "THEZOCQS",
    175     "HEZLOCUS",
    176     "fijkdbh",
    177     "xzroesc",
    178     "xzroesc",
    179     "pqgjy"
    180   };
    181 
    182 
    183   static void
    184   af_latin2_metrics_init_blues( AF_LatinMetrics  metrics,
    185                                 FT_Face          face )
    186   {
    187     FT_Pos        flats [AF_LATIN_MAX_TEST_CHARACTERS];
    188     FT_Pos        rounds[AF_LATIN_MAX_TEST_CHARACTERS];
    189     FT_Int        num_flats;
    190     FT_Int        num_rounds;
    191     FT_Int        bb;
    192     AF_LatinBlue  blue;
    193     FT_Error      error;
    194     AF_LatinAxis  axis  = &metrics->axis[AF_DIMENSION_VERT];
    195     FT_GlyphSlot  glyph = face->glyph;
    196 
    197 
    198     /* we compute the blues simply by loading each character from the     */
    199     /* 'af_latin2_blue_chars[blues]' string, then compute its top-most or */
    200     /* bottom-most points (depending on `AF_IS_TOP_BLUE')                 */
    201 
    202     FT_TRACE5(( "blue zones computation\n"
    203                 "======================\n\n" ));
    204 
    205     for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
    206     {
    207       const char*  p     = af_latin2_blue_chars[bb];
    208       const char*  limit = p + AF_LATIN_MAX_TEST_CHARACTERS;
    209       FT_Pos*      blue_ref;
    210       FT_Pos*      blue_shoot;
    211 
    212 
    213       FT_TRACE5(( "blue zone %d:\n", bb ));
    214 
    215       num_flats  = 0;
    216       num_rounds = 0;
    217 
    218       for ( ; p < limit && *p; p++ )
    219       {
    220         FT_UInt     glyph_index;
    221         FT_Int      best_point, best_y, best_first, best_last;
    222         FT_Vector*  points;
    223         FT_Bool     round;
    224 
    225 
    226         /* load the character in the face -- skip unknown or empty ones */
    227         glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p );
    228         if ( glyph_index == 0 )
    229           continue;
    230 
    231         error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
    232         if ( error || glyph->outline.n_points <= 0 )
    233           continue;
    234 
    235         /* now compute min or max point indices and coordinates */
    236         points      = glyph->outline.points;
    237         best_point  = -1;
    238         best_y      = 0;  /* make compiler happy */
    239         best_first  = 0;  /* ditto */
    240         best_last   = 0;  /* ditto */
    241 
    242         {
    243           FT_Int  nn;
    244           FT_Int  first = 0;
    245           FT_Int  last  = -1;
    246 
    247 
    248           for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ )
    249           {
    250             FT_Int  old_best_point = best_point;
    251             FT_Int  pp;
    252 
    253 
    254             last = glyph->outline.contours[nn];
    255 
    256             /* Avoid single-point contours since they are never rasterized. */
    257             /* In some fonts, they correspond to mark attachment points     */
    258             /* which are way outside of the glyph's real outline.           */
    259             if ( last == first )
    260                 continue;
    261 
    262             if ( AF_LATIN_IS_TOP_BLUE( bb ) )
    263             {
    264               for ( pp = first; pp <= last; pp++ )
    265                 if ( best_point < 0 || points[pp].y > best_y )
    266                 {
    267                   best_point = pp;
    268                   best_y     = points[pp].y;
    269                 }
    270             }
    271             else
    272             {
    273               for ( pp = first; pp <= last; pp++ )
    274                 if ( best_point < 0 || points[pp].y < best_y )
    275                 {
    276                   best_point = pp;
    277                   best_y     = points[pp].y;
    278                 }
    279             }
    280 
    281             if ( best_point != old_best_point )
    282             {
    283               best_first = first;
    284               best_last  = last;
    285             }
    286           }
    287           FT_TRACE5(( "  %c  %d", *p, best_y ));
    288         }
    289 
    290         /* now check whether the point belongs to a straight or round   */
    291         /* segment; we first need to find in which contour the extremum */
    292         /* lies, then inspect its previous and next points              */
    293         {
    294           FT_Pos  best_x = points[best_point].x;
    295           FT_Int  start, end, prev, next;
    296           FT_Pos  dist;
    297 
    298 
    299           /* now look for the previous and next points that are not on the */
    300           /* same Y coordinate.  Threshold the `closeness'...              */
    301           start = end = best_point;
    302 
    303           do
    304           {
    305             prev = start - 1;
    306             if ( prev < best_first )
    307               prev = best_last;
    308 
    309             dist = FT_ABS( points[prev].y - best_y );
    310             /* accept a small distance or a small angle (both values are */
    311             /* heuristic; value 20 corresponds to approx. 2.9 degrees)   */
    312             if ( dist > 5 )
    313               if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist )
    314                 break;
    315 
    316             start = prev;
    317 
    318           } while ( start != best_point );
    319 
    320           do
    321           {
    322             next = end + 1;
    323             if ( next > best_last )
    324               next = best_first;
    325 
    326             dist = FT_ABS( points[next].y - best_y );
    327             if ( dist > 5 )
    328               if ( FT_ABS( points[next].x - best_x ) <= 20 * dist )
    329                 break;
    330 
    331             end = next;
    332 
    333           } while ( end != best_point );
    334 
    335           /* now, set the `round' flag depending on the segment's kind */
    336           round = FT_BOOL(
    337             FT_CURVE_TAG( glyph->outline.tags[start] ) != FT_CURVE_TAG_ON ||
    338             FT_CURVE_TAG( glyph->outline.tags[ end ] ) != FT_CURVE_TAG_ON );
    339 
    340           FT_TRACE5(( " (%s)\n", round ? "round" : "flat" ));
    341         }
    342 
    343         if ( round )
    344           rounds[num_rounds++] = best_y;
    345         else
    346           flats[num_flats++]   = best_y;
    347       }
    348 
    349       if ( num_flats == 0 && num_rounds == 0 )
    350       {
    351         /*
    352          *  we couldn't find a single glyph to compute this blue zone,
    353          *  we will simply ignore it then
    354          */
    355         FT_TRACE5(( "  empty\n" ));
    356         continue;
    357       }
    358 
    359       /* we have computed the contents of the `rounds' and `flats' tables, */
    360       /* now determine the reference and overshoot position of the blue -- */
    361       /* we simply take the median value after a simple sort               */
    362       af_sort_pos( num_rounds, rounds );
    363       af_sort_pos( num_flats,  flats );
    364 
    365       blue       = & axis->blues[axis->blue_count];
    366       blue_ref   = & blue->ref.org;
    367       blue_shoot = & blue->shoot.org;
    368 
    369       axis->blue_count++;
    370 
    371       if ( num_flats == 0 )
    372       {
    373         *blue_ref   =
    374         *blue_shoot = rounds[num_rounds / 2];
    375       }
    376       else if ( num_rounds == 0 )
    377       {
    378         *blue_ref   =
    379         *blue_shoot = flats[num_flats / 2];
    380       }
    381       else
    382       {
    383         *blue_ref   = flats[num_flats / 2];
    384         *blue_shoot = rounds[num_rounds / 2];
    385       }
    386 
    387       /* there are sometimes problems: if the overshoot position of top     */
    388       /* zones is under its reference position, or the opposite for bottom  */
    389       /* zones.  We must thus check everything there and correct the errors */
    390       if ( *blue_shoot != *blue_ref )
    391       {
    392         FT_Pos   ref      = *blue_ref;
    393         FT_Pos   shoot    = *blue_shoot;
    394         FT_Bool  over_ref = FT_BOOL( shoot > ref );
    395 
    396 
    397         if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref )
    398         {
    399           *blue_ref   =
    400           *blue_shoot = ( shoot + ref ) / 2;
    401 
    402           FT_TRACE5(( "  [overshoot smaller than reference,"
    403                       " taking mean value]\n" ));
    404         }
    405       }
    406 
    407       blue->flags = 0;
    408       if ( AF_LATIN_IS_TOP_BLUE( bb ) )
    409         blue->flags |= AF_LATIN_BLUE_TOP;
    410 
    411       /*
    412        * The following flags is used later to adjust the y and x scales
    413        * in order to optimize the pixel grid alignment of the top of small
    414        * letters.
    415        */
    416       if ( bb == AF_LATIN_BLUE_SMALL_TOP )
    417         blue->flags |= AF_LATIN_BLUE_ADJUSTMENT;
    418 
    419       FT_TRACE5(( "    -> reference = %ld\n"
    420                   "       overshoot = %ld\n",
    421                   *blue_ref, *blue_shoot ));
    422     }
    423 
    424     return;
    425   }
    426 
    427 
    428   FT_LOCAL_DEF( void )
    429   af_latin2_metrics_check_digits( AF_LatinMetrics  metrics,
    430                                   FT_Face          face )
    431   {
    432     FT_UInt   i;
    433     FT_Bool   started = 0, same_width = 1;
    434     FT_Fixed  advance, old_advance = 0;
    435 
    436 
    437     /* check whether all ASCII digits have the same advance width; */
    438     /* digit `0' is 0x30 in all supported charmaps                 */
    439     for ( i = 0x30; i <= 0x39; i++ )
    440     {
    441       FT_UInt  glyph_index;
    442 
    443 
    444       glyph_index = FT_Get_Char_Index( face, i );
    445       if ( glyph_index == 0 )
    446         continue;
    447 
    448       if ( FT_Get_Advance( face, glyph_index,
    449                            FT_LOAD_NO_SCALE         |
    450                            FT_LOAD_NO_HINTING       |
    451                            FT_LOAD_IGNORE_TRANSFORM,
    452                            &advance ) )
    453         continue;
    454 
    455       if ( started )
    456       {
    457         if ( advance != old_advance )
    458         {
    459           same_width = 0;
    460           break;
    461         }
    462       }
    463       else
    464       {
    465         old_advance = advance;
    466         started     = 1;
    467       }
    468     }
    469 
    470     metrics->root.digits_have_same_width = same_width;
    471   }
    472 
    473 
    474   FT_LOCAL_DEF( FT_Error )
    475   af_latin2_metrics_init( AF_LatinMetrics  metrics,
    476                           FT_Face          face )
    477   {
    478     FT_Error    error  = FT_Err_Ok;
    479     FT_CharMap  oldmap = face->charmap;
    480     FT_UInt     ee;
    481 
    482     static const FT_Encoding  latin_encodings[] =
    483     {
    484       FT_ENCODING_UNICODE,
    485       FT_ENCODING_APPLE_ROMAN,
    486       FT_ENCODING_ADOBE_STANDARD,
    487       FT_ENCODING_ADOBE_LATIN_1,
    488       FT_ENCODING_NONE  /* end of list */
    489     };
    490 
    491 
    492     metrics->units_per_em = face->units_per_EM;
    493 
    494     /* do we have a latin charmap in there? */
    495     for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ )
    496     {
    497       error = FT_Select_Charmap( face, latin_encodings[ee] );
    498       if ( !error )
    499         break;
    500     }
    501 
    502     if ( !error )
    503     {
    504       af_latin2_metrics_init_widths( metrics, face );
    505       af_latin2_metrics_init_blues( metrics, face );
    506       af_latin2_metrics_check_digits( metrics, face );
    507     }
    508 
    509     FT_Set_Charmap( face, oldmap );
    510     return FT_Err_Ok;
    511   }
    512 
    513 
    514   static void
    515   af_latin2_metrics_scale_dim( AF_LatinMetrics  metrics,
    516                                AF_Scaler        scaler,
    517                                AF_Dimension     dim )
    518   {
    519     FT_Fixed      scale;
    520     FT_Pos        delta;
    521     AF_LatinAxis  axis;
    522     FT_UInt       nn;
    523 
    524 
    525     if ( dim == AF_DIMENSION_HORZ )
    526     {
    527       scale = scaler->x_scale;
    528       delta = scaler->x_delta;
    529     }
    530     else
    531     {
    532       scale = scaler->y_scale;
    533       delta = scaler->y_delta;
    534     }
    535 
    536     axis = &metrics->axis[dim];
    537 
    538     if ( axis->org_scale == scale && axis->org_delta == delta )
    539       return;
    540 
    541     axis->org_scale = scale;
    542     axis->org_delta = delta;
    543 
    544     /*
    545      * correct Y scale to optimize the alignment of the top of small
    546      * letters to the pixel grid
    547      */
    548     if ( dim == AF_DIMENSION_VERT )
    549     {
    550       AF_LatinAxis  vaxis = &metrics->axis[AF_DIMENSION_VERT];
    551       AF_LatinBlue  blue = NULL;
    552 
    553 
    554       for ( nn = 0; nn < vaxis->blue_count; nn++ )
    555       {
    556         if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT )
    557         {
    558           blue = &vaxis->blues[nn];
    559           break;
    560         }
    561       }
    562 
    563       if ( blue )
    564       {
    565         FT_Pos   scaled;
    566         FT_Pos   threshold;
    567         FT_Pos   fitted;
    568         FT_UInt  limit;
    569         FT_UInt  ppem;
    570 
    571 
    572         scaled    = FT_MulFix( blue->shoot.org, scaler->y_scale );
    573         ppem      = metrics->root.scaler.face->size->metrics.x_ppem;
    574         limit     = metrics->root.globals->increase_x_height;
    575         threshold = 40;
    576 
    577         /* if the `increase-x-height' property is active, */
    578         /* we round up much more often                    */
    579         if ( limit                                 &&
    580              ppem <= limit                         &&
    581              ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN )
    582           threshold = 52;
    583 
    584         fitted = ( scaled + threshold ) & ~63;
    585 
    586 #if 1
    587         if ( scaled != fitted )
    588         {
    589           scale = FT_MulDiv( scale, fitted, scaled );
    590           FT_TRACE5(( "== scaled x-top = %.2g"
    591                       "  fitted = %.2g, scaling = %.4g\n",
    592                       scaled / 64.0, fitted / 64.0,
    593                       ( fitted * 1.0 ) / scaled ));
    594         }
    595 #endif
    596       }
    597     }
    598 
    599     axis->scale = scale;
    600     axis->delta = delta;
    601 
    602     if ( dim == AF_DIMENSION_HORZ )
    603     {
    604       metrics->root.scaler.x_scale = scale;
    605       metrics->root.scaler.x_delta = delta;
    606     }
    607     else
    608     {
    609       metrics->root.scaler.y_scale = scale;
    610       metrics->root.scaler.y_delta = delta;
    611     }
    612 
    613     /* scale the standard widths */
    614     for ( nn = 0; nn < axis->width_count; nn++ )
    615     {
    616       AF_Width  width = axis->widths + nn;
    617 
    618 
    619       width->cur = FT_MulFix( width->org, scale );
    620       width->fit = width->cur;
    621     }
    622 
    623     /* an extra-light axis corresponds to a standard width that is */
    624     /* smaller than 5/8 pixels                                     */
    625     axis->extra_light =
    626       (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 );
    627 
    628     if ( dim == AF_DIMENSION_VERT )
    629     {
    630       /* scale the blue zones */
    631       for ( nn = 0; nn < axis->blue_count; nn++ )
    632       {
    633         AF_LatinBlue  blue = &axis->blues[nn];
    634         FT_Pos        dist;
    635 
    636 
    637         blue->ref.cur   = FT_MulFix( blue->ref.org, scale ) + delta;
    638         blue->ref.fit   = blue->ref.cur;
    639         blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
    640         blue->shoot.fit = blue->shoot.cur;
    641         blue->flags    &= ~AF_LATIN_BLUE_ACTIVE;
    642 
    643         /* a blue zone is only active if it is less than 3/4 pixels tall */
    644         dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
    645         if ( dist <= 48 && dist >= -48 )
    646         {
    647           FT_Pos  delta1, delta2;
    648 
    649           delta1 = blue->shoot.org - blue->ref.org;
    650           delta2 = delta1;
    651           if ( delta1 < 0 )
    652             delta2 = -delta2;
    653 
    654           delta2 = FT_MulFix( delta2, scale );
    655 
    656           if ( delta2 < 32 )
    657             delta2 = 0;
    658           else if ( delta2 < 64 )
    659             delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
    660           else
    661             delta2 = FT_PIX_ROUND( delta2 );
    662 
    663           if ( delta1 < 0 )
    664             delta2 = -delta2;
    665 
    666           blue->ref.fit   = FT_PIX_ROUND( blue->ref.cur );
    667           blue->shoot.fit = blue->ref.fit + delta2;
    668 
    669           FT_TRACE5(( ">> activating blue zone %d:"
    670                       "  ref.cur=%.2g ref.fit=%.2g"
    671                       "  shoot.cur=%.2g shoot.fit=%.2g\n",
    672                       nn, blue->ref.cur / 64.0, blue->ref.fit / 64.0,
    673                       blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 ));
    674 
    675           blue->flags |= AF_LATIN_BLUE_ACTIVE;
    676         }
    677       }
    678     }
    679   }
    680 
    681 
    682   FT_LOCAL_DEF( void )
    683   af_latin2_metrics_scale( AF_LatinMetrics  metrics,
    684                            AF_Scaler        scaler )
    685   {
    686     metrics->root.scaler.render_mode = scaler->render_mode;
    687     metrics->root.scaler.face        = scaler->face;
    688     metrics->root.scaler.flags       = scaler->flags;
    689 
    690     af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
    691     af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
    692   }
    693 
    694 
    695   /*************************************************************************/
    696   /*************************************************************************/
    697   /*****                                                               *****/
    698   /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
    699   /*****                                                               *****/
    700   /*************************************************************************/
    701   /*************************************************************************/
    702 
    703 #define  SORT_SEGMENTS
    704 
    705   FT_LOCAL_DEF( FT_Error )
    706   af_latin2_hints_compute_segments( AF_GlyphHints  hints,
    707                                     AF_Dimension   dim )
    708   {
    709     AF_AxisHints  axis          = &hints->axis[dim];
    710     FT_Memory     memory        = hints->memory;
    711     FT_Error      error         = FT_Err_Ok;
    712     AF_Segment    segment       = NULL;
    713     AF_SegmentRec seg0;
    714     AF_Point*     contour       = hints->contours;
    715     AF_Point*     contour_limit = contour + hints->num_contours;
    716     AF_Direction  major_dir, segment_dir;
    717 
    718 
    719     FT_ZERO( &seg0 );
    720     seg0.score = 32000;
    721     seg0.flags = AF_EDGE_NORMAL;
    722 
    723     major_dir   = (AF_Direction)FT_ABS( axis->major_dir );
    724     segment_dir = major_dir;
    725 
    726     axis->num_segments = 0;
    727 
    728     /* set up (u,v) in each point */
    729     if ( dim == AF_DIMENSION_HORZ )
    730     {
    731       AF_Point  point = hints->points;
    732       AF_Point  limit = point + hints->num_points;
    733 
    734 
    735       for ( ; point < limit; point++ )
    736       {
    737         point->u = point->fx;
    738         point->v = point->fy;
    739       }
    740     }
    741     else
    742     {
    743       AF_Point  point = hints->points;
    744       AF_Point  limit = point + hints->num_points;
    745 
    746 
    747       for ( ; point < limit; point++ )
    748       {
    749         point->u = point->fy;
    750         point->v = point->fx;
    751       }
    752     }
    753 
    754     /* do each contour separately */
    755     for ( ; contour < contour_limit; contour++ )
    756     {
    757       AF_Point  point   =  contour[0];
    758       AF_Point  start   =  point;
    759       AF_Point  last    =  point->prev;
    760 
    761 
    762       if ( point == last )  /* skip singletons -- just in case */
    763         continue;
    764 
    765       /* already on an edge ?, backtrack to find its start */
    766       if ( FT_ABS( point->in_dir ) == major_dir )
    767       {
    768         point = point->prev;
    769 
    770         while ( point->in_dir == start->in_dir )
    771           point = point->prev;
    772       }
    773       else  /* otherwise, find first segment start, if any */
    774       {
    775         while ( FT_ABS( point->out_dir ) != major_dir )
    776         {
    777           point = point->next;
    778 
    779           if ( point == start )
    780             goto NextContour;
    781         }
    782       }
    783 
    784       start = point;
    785 
    786       for  (;;)
    787       {
    788         AF_Point  first;
    789         FT_Pos    min_u, min_v, max_u, max_v;
    790 
    791         /* we're at the start of a new segment */
    792         FT_ASSERT( FT_ABS( point->out_dir ) == major_dir &&
    793                            point->in_dir != point->out_dir );
    794         first = point;
    795 
    796         min_u = max_u = point->u;
    797         min_v = max_v = point->v;
    798 
    799         point = point->next;
    800 
    801         while ( point->out_dir == first->out_dir )
    802         {
    803           point = point->next;
    804 
    805           if ( point->u < min_u )
    806             min_u = point->u;
    807 
    808           if ( point->u > max_u )
    809             max_u = point->u;
    810         }
    811 
    812         if ( point->v < min_v )
    813           min_v = point->v;
    814 
    815         if ( point->v > max_v )
    816           max_v = point->v;
    817 
    818         /* record new segment */
    819         error = af_axis_hints_new_segment( axis, memory, &segment );
    820         if ( error )
    821           goto Exit;
    822 
    823         segment[0]         = seg0;
    824         segment->dir       = first->out_dir;
    825         segment->first     = first;
    826         segment->last      = point;
    827         segment->pos       = (FT_Short)( ( min_u + max_u ) >> 1 );
    828         segment->min_coord = (FT_Short) min_v;
    829         segment->max_coord = (FT_Short) max_v;
    830         segment->height    = (FT_Short)( max_v - min_v );
    831 
    832         /* a segment is round if it doesn't have successive */
    833         /* on-curve points.                                 */
    834         {
    835           AF_Point  pt   = first;
    836           AF_Point  last = point;
    837           AF_Flags  f0   = (AF_Flags)( pt->flags & AF_FLAG_CONTROL );
    838           AF_Flags  f1;
    839 
    840 
    841           segment->flags &= ~AF_EDGE_ROUND;
    842 
    843           for ( ; pt != last; f0 = f1 )
    844           {
    845             pt = pt->next;
    846             f1 = (AF_Flags)( pt->flags & AF_FLAG_CONTROL );
    847 
    848             if ( !f0 && !f1 )
    849               break;
    850 
    851             if ( pt == last )
    852               segment->flags |= AF_EDGE_ROUND;
    853           }
    854         }
    855 
    856        /* this can happen in the case of a degenerate contour
    857         * e.g. a 2-point vertical contour
    858         */
    859         if ( point == start )
    860           break;
    861 
    862         /* jump to the start of the next segment, if any */
    863         while ( FT_ABS( point->out_dir ) != major_dir )
    864         {
    865           point = point->next;
    866 
    867           if ( point == start )
    868             goto NextContour;
    869         }
    870       }
    871 
    872     NextContour:
    873       ;
    874     } /* contours */
    875 
    876     /* now slightly increase the height of segments when this makes */
    877     /* sense -- this is used to better detect and ignore serifs     */
    878     {
    879       AF_Segment  segments     = axis->segments;
    880       AF_Segment  segments_end = segments + axis->num_segments;
    881 
    882 
    883       for ( segment = segments; segment < segments_end; segment++ )
    884       {
    885         AF_Point  first   = segment->first;
    886         AF_Point  last    = segment->last;
    887         AF_Point  p;
    888         FT_Pos    first_v = first->v;
    889         FT_Pos    last_v  = last->v;
    890 
    891 
    892         if ( first == last )
    893           continue;
    894 
    895         if ( first_v < last_v )
    896         {
    897           p = first->prev;
    898           if ( p->v < first_v )
    899             segment->height = (FT_Short)( segment->height +
    900                                           ( ( first_v - p->v ) >> 1 ) );
    901 
    902           p = last->next;
    903           if ( p->v > last_v )
    904             segment->height = (FT_Short)( segment->height +
    905                                           ( ( p->v - last_v ) >> 1 ) );
    906         }
    907         else
    908         {
    909           p = first->prev;
    910           if ( p->v > first_v )
    911             segment->height = (FT_Short)( segment->height +
    912                                           ( ( p->v - first_v ) >> 1 ) );
    913 
    914           p = last->next;
    915           if ( p->v < last_v )
    916             segment->height = (FT_Short)( segment->height +
    917                                           ( ( last_v - p->v ) >> 1 ) );
    918         }
    919       }
    920     }
    921 
    922 #ifdef AF_SORT_SEGMENTS
    923    /* place all segments with a negative direction to the start
    924     * of the array, used to speed up segment linking later...
    925     */
    926     {
    927       AF_Segment  segments = axis->segments;
    928       FT_UInt     count    = axis->num_segments;
    929       FT_UInt     ii, jj;
    930 
    931       for ( ii = 0; ii < count; ii++ )
    932       {
    933         if ( segments[ii].dir > 0 )
    934         {
    935           for ( jj = ii + 1; jj < count; jj++ )
    936           {
    937             if ( segments[jj].dir < 0 )
    938             {
    939               AF_SegmentRec  tmp;
    940 
    941 
    942               tmp          = segments[ii];
    943               segments[ii] = segments[jj];
    944               segments[jj] = tmp;
    945 
    946               break;
    947             }
    948           }
    949 
    950           if ( jj == count )
    951             break;
    952         }
    953       }
    954       axis->mid_segments = ii;
    955     }
    956 #endif
    957 
    958   Exit:
    959     return error;
    960   }
    961 
    962 
    963   FT_LOCAL_DEF( void )
    964   af_latin2_hints_link_segments( AF_GlyphHints  hints,
    965                                  AF_Dimension   dim )
    966   {
    967     AF_AxisHints  axis          = &hints->axis[dim];
    968     AF_Segment    segments      = axis->segments;
    969     AF_Segment    segment_limit = segments + axis->num_segments;
    970 #ifdef AF_SORT_SEGMENTS
    971     AF_Segment    segment_mid   = segments + axis->mid_segments;
    972 #endif
    973     FT_Pos        len_threshold, len_score;
    974     AF_Segment    seg1, seg2;
    975 
    976 
    977     len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
    978     if ( len_threshold == 0 )
    979       len_threshold = 1;
    980 
    981     len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 );
    982 
    983 #ifdef AF_SORT_SEGMENTS
    984     for ( seg1 = segments; seg1 < segment_mid; seg1++ )
    985     {
    986       if ( seg1->dir != axis->major_dir || seg1->first == seg1->last )
    987         continue;
    988 
    989       for ( seg2 = segment_mid; seg2 < segment_limit; seg2++ )
    990 #else
    991     /* now compare each segment to the others */
    992     for ( seg1 = segments; seg1 < segment_limit; seg1++ )
    993     {
    994       /* the fake segments are introduced to hint the metrics -- */
    995       /* we must never link them to anything                     */
    996       if ( seg1->dir != axis->major_dir || seg1->first == seg1->last )
    997         continue;
    998 
    999       for ( seg2 = segments; seg2 < segment_limit; seg2++ )
   1000         if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos )
   1001 #endif
   1002         {
   1003           FT_Pos  pos1 = seg1->pos;
   1004           FT_Pos  pos2 = seg2->pos;
   1005           FT_Pos  dist = pos2 - pos1;
   1006 
   1007 
   1008           if ( dist < 0 )
   1009             continue;
   1010 
   1011           {
   1012             FT_Pos  min = seg1->min_coord;
   1013             FT_Pos  max = seg1->max_coord;
   1014             FT_Pos  len, score;
   1015 
   1016 
   1017             if ( min < seg2->min_coord )
   1018               min = seg2->min_coord;
   1019 
   1020             if ( max > seg2->max_coord )
   1021               max = seg2->max_coord;
   1022 
   1023             len = max - min;
   1024             if ( len >= len_threshold )
   1025             {
   1026               score = dist + len_score / len;
   1027               if ( score < seg1->score )
   1028               {
   1029                 seg1->score = score;
   1030                 seg1->link  = seg2;
   1031               }
   1032 
   1033               if ( score < seg2->score )
   1034               {
   1035                 seg2->score = score;
   1036                 seg2->link  = seg1;
   1037               }
   1038             }
   1039           }
   1040         }
   1041     }
   1042 #if 0
   1043     }
   1044 #endif
   1045 
   1046     /* now, compute the `serif' segments */
   1047     for ( seg1 = segments; seg1 < segment_limit; seg1++ )
   1048     {
   1049       seg2 = seg1->link;
   1050 
   1051       if ( seg2 )
   1052       {
   1053         if ( seg2->link != seg1 )
   1054         {
   1055           seg1->link  = 0;
   1056           seg1->serif = seg2->link;
   1057         }
   1058       }
   1059     }
   1060   }
   1061 
   1062 
   1063   FT_LOCAL_DEF( FT_Error )
   1064   af_latin2_hints_compute_edges( AF_GlyphHints  hints,
   1065                                  AF_Dimension   dim )
   1066   {
   1067     AF_AxisHints  axis   = &hints->axis[dim];
   1068     FT_Error      error  = FT_Err_Ok;
   1069     FT_Memory     memory = hints->memory;
   1070     AF_LatinAxis  laxis  = &((AF_LatinMetrics)hints->metrics)->axis[dim];
   1071 
   1072     AF_Segment    segments      = axis->segments;
   1073     AF_Segment    segment_limit = segments + axis->num_segments;
   1074     AF_Segment    seg;
   1075 
   1076     AF_Direction  up_dir;
   1077     FT_Fixed      scale;
   1078     FT_Pos        edge_distance_threshold;
   1079     FT_Pos        segment_length_threshold;
   1080 
   1081 
   1082     axis->num_edges = 0;
   1083 
   1084     scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
   1085                                          : hints->y_scale;
   1086 
   1087     up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP
   1088                                           : AF_DIR_RIGHT;
   1089 
   1090     /*
   1091      *  We want to ignore very small (mostly serif) segments, we do that
   1092      *  by ignoring those that whose length is less than a given fraction
   1093      *  of the standard width. If there is no standard width, we ignore
   1094      *  those that are less than a given size in pixels
   1095      *
   1096      *  also, unlink serif segments that are linked to segments farther
   1097      *  than 50% of the standard width
   1098      */
   1099     if ( dim == AF_DIMENSION_HORZ )
   1100     {
   1101       if ( laxis->width_count > 0 )
   1102         segment_length_threshold = ( laxis->standard_width * 10 ) >> 4;
   1103       else
   1104         segment_length_threshold = FT_DivFix( 64, hints->y_scale );
   1105     }
   1106     else
   1107       segment_length_threshold = 0;
   1108 
   1109     /*********************************************************************/
   1110     /*                                                                   */
   1111     /* We will begin by generating a sorted table of edges for the       */
   1112     /* current direction.  To do so, we simply scan each segment and try */
   1113     /* to find an edge in our table that corresponds to its position.    */
   1114     /*                                                                   */
   1115     /* If no edge is found, we create and insert a new edge in the       */
   1116     /* sorted table.  Otherwise, we simply add the segment to the edge's */
   1117     /* list which will be processed in the second step to compute the    */
   1118     /* edge's properties.                                                */
   1119     /*                                                                   */
   1120     /* Note that the edges table is sorted along the segment/edge        */
   1121     /* position.                                                         */
   1122     /*                                                                   */
   1123     /*********************************************************************/
   1124 
   1125     edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
   1126                                          scale );
   1127     if ( edge_distance_threshold > 64 / 4 )
   1128       edge_distance_threshold = 64 / 4;
   1129 
   1130     edge_distance_threshold = FT_DivFix( edge_distance_threshold,
   1131                                          scale );
   1132 
   1133     for ( seg = segments; seg < segment_limit; seg++ )
   1134     {
   1135       AF_Edge  found = 0;
   1136       FT_Int   ee;
   1137 
   1138 
   1139       if ( seg->height < segment_length_threshold )
   1140         continue;
   1141 
   1142       /* A special case for serif edges: If they are smaller than */
   1143       /* 1.5 pixels we ignore them.                               */
   1144       if ( seg->serif )
   1145       {
   1146         FT_Pos  dist = seg->serif->pos - seg->pos;
   1147 
   1148 
   1149         if ( dist < 0 )
   1150           dist = -dist;
   1151 
   1152         if ( dist >= laxis->standard_width >> 1 )
   1153         {
   1154           /* unlink this serif, it is too distant from its reference stem */
   1155           seg->serif = NULL;
   1156         }
   1157         else if ( 2*seg->height < 3 * segment_length_threshold )
   1158           continue;
   1159       }
   1160 
   1161       /* look for an edge corresponding to the segment */
   1162       for ( ee = 0; ee < axis->num_edges; ee++ )
   1163       {
   1164         AF_Edge  edge = axis->edges + ee;
   1165         FT_Pos   dist;
   1166 
   1167 
   1168         dist = seg->pos - edge->fpos;
   1169         if ( dist < 0 )
   1170           dist = -dist;
   1171 
   1172         if ( dist < edge_distance_threshold && edge->dir == seg->dir )
   1173         {
   1174           found = edge;
   1175           break;
   1176         }
   1177       }
   1178 
   1179       if ( !found )
   1180       {
   1181         AF_Edge   edge;
   1182 
   1183 
   1184         /* insert a new edge in the list and */
   1185         /* sort according to the position    */
   1186         error = af_axis_hints_new_edge( axis, seg->pos, seg->dir,
   1187                                         memory, &edge );
   1188         if ( error )
   1189           goto Exit;
   1190 
   1191         /* add the segment to the new edge's list */
   1192         FT_ZERO( edge );
   1193 
   1194         edge->first    = seg;
   1195         edge->last     = seg;
   1196         edge->fpos     = seg->pos;
   1197         edge->dir      = seg->dir;
   1198         edge->opos     = edge->pos = FT_MulFix( seg->pos, scale );
   1199         seg->edge_next = seg;
   1200       }
   1201       else
   1202       {
   1203         /* if an edge was found, simply add the segment to the edge's */
   1204         /* list                                                       */
   1205         seg->edge_next         = found->first;
   1206         found->last->edge_next = seg;
   1207         found->last            = seg;
   1208       }
   1209     }
   1210 
   1211 
   1212     /*********************************************************************/
   1213     /*                                                                   */
   1214     /* Good, we will now compute each edge's properties according to     */
   1215     /* segments found on its position.  Basically, these are:            */
   1216     /*                                                                   */
   1217     /*  - edge's main direction                                          */
   1218     /*  - stem edge, serif edge or both (which defaults to stem then)    */
   1219     /*  - rounded edge, straight or both (which defaults to straight)    */
   1220     /*  - link for edge                                                  */
   1221     /*                                                                   */
   1222     /*********************************************************************/
   1223 
   1224     /* first of all, set the `edge' field in each segment -- this is */
   1225     /* required in order to compute edge links                       */
   1226 
   1227     /*
   1228      * Note that removing this loop and setting the `edge' field of each
   1229      * segment directly in the code above slows down execution speed for
   1230      * some reasons on platforms like the Sun.
   1231      */
   1232     {
   1233       AF_Edge  edges      = axis->edges;
   1234       AF_Edge  edge_limit = edges + axis->num_edges;
   1235       AF_Edge  edge;
   1236 
   1237 
   1238       for ( edge = edges; edge < edge_limit; edge++ )
   1239       {
   1240         seg = edge->first;
   1241         if ( seg )
   1242           do
   1243           {
   1244             seg->edge = edge;
   1245             seg       = seg->edge_next;
   1246 
   1247           } while ( seg != edge->first );
   1248       }
   1249 
   1250       /* now, compute each edge properties */
   1251       for ( edge = edges; edge < edge_limit; edge++ )
   1252       {
   1253         FT_Int  is_round    = 0;  /* does it contain round segments?    */
   1254         FT_Int  is_straight = 0;  /* does it contain straight segments? */
   1255 #if 0
   1256         FT_Pos  ups         = 0;  /* number of upwards segments         */
   1257         FT_Pos  downs       = 0;  /* number of downwards segments       */
   1258 #endif
   1259 
   1260 
   1261         seg = edge->first;
   1262 
   1263         do
   1264         {
   1265           FT_Bool  is_serif;
   1266 
   1267 
   1268           /* check for roundness of segment */
   1269           if ( seg->flags & AF_EDGE_ROUND )
   1270             is_round++;
   1271           else
   1272             is_straight++;
   1273 
   1274 #if 0
   1275           /* check for segment direction */
   1276           if ( seg->dir == up_dir )
   1277             ups   += seg->max_coord-seg->min_coord;
   1278           else
   1279             downs += seg->max_coord-seg->min_coord;
   1280 #endif
   1281 
   1282           /* check for links -- if seg->serif is set, then seg->link must */
   1283           /* be ignored                                                   */
   1284           is_serif = (FT_Bool)( seg->serif               &&
   1285                                 seg->serif->edge         &&
   1286                                 seg->serif->edge != edge );
   1287 
   1288           if ( ( seg->link && seg->link->edge != NULL ) || is_serif )
   1289           {
   1290             AF_Edge     edge2;
   1291             AF_Segment  seg2;
   1292 
   1293 
   1294             edge2 = edge->link;
   1295             seg2  = seg->link;
   1296 
   1297             if ( is_serif )
   1298             {
   1299               seg2  = seg->serif;
   1300               edge2 = edge->serif;
   1301             }
   1302 
   1303             if ( edge2 )
   1304             {
   1305               FT_Pos  edge_delta;
   1306               FT_Pos  seg_delta;
   1307 
   1308 
   1309               edge_delta = edge->fpos - edge2->fpos;
   1310               if ( edge_delta < 0 )
   1311                 edge_delta = -edge_delta;
   1312 
   1313               seg_delta = seg->pos - seg2->pos;
   1314               if ( seg_delta < 0 )
   1315                 seg_delta = -seg_delta;
   1316 
   1317               if ( seg_delta < edge_delta )
   1318                 edge2 = seg2->edge;
   1319             }
   1320             else
   1321               edge2 = seg2->edge;
   1322 
   1323             if ( is_serif )
   1324             {
   1325               edge->serif   = edge2;
   1326               edge2->flags |= AF_EDGE_SERIF;
   1327             }
   1328             else
   1329               edge->link  = edge2;
   1330           }
   1331 
   1332           seg = seg->edge_next;
   1333 
   1334         } while ( seg != edge->first );
   1335 
   1336         /* set the round/straight flags */
   1337         edge->flags = AF_EDGE_NORMAL;
   1338 
   1339         if ( is_round > 0 && is_round >= is_straight )
   1340           edge->flags |= AF_EDGE_ROUND;
   1341 
   1342 #if 0
   1343         /* set the edge's main direction */
   1344         edge->dir = AF_DIR_NONE;
   1345 
   1346         if ( ups > downs )
   1347           edge->dir = (FT_Char)up_dir;
   1348 
   1349         else if ( ups < downs )
   1350           edge->dir = (FT_Char)-up_dir;
   1351 
   1352         else if ( ups == downs )
   1353           edge->dir = 0;  /* both up and down! */
   1354 #endif
   1355 
   1356         /* gets rid of serifs if link is set                */
   1357         /* XXX: This gets rid of many unpleasant artefacts! */
   1358         /*      Example: the `c' in cour.pfa at size 13     */
   1359 
   1360         if ( edge->serif && edge->link )
   1361           edge->serif = 0;
   1362       }
   1363     }
   1364 
   1365   Exit:
   1366     return error;
   1367   }
   1368 
   1369 
   1370   FT_LOCAL_DEF( FT_Error )
   1371   af_latin2_hints_detect_features( AF_GlyphHints  hints,
   1372                                    AF_Dimension   dim )
   1373   {
   1374     FT_Error  error;
   1375 
   1376 
   1377     error = af_latin2_hints_compute_segments( hints, dim );
   1378     if ( !error )
   1379     {
   1380       af_latin2_hints_link_segments( hints, dim );
   1381 
   1382       error = af_latin2_hints_compute_edges( hints, dim );
   1383     }
   1384     return error;
   1385   }
   1386 
   1387 
   1388   FT_LOCAL_DEF( void )
   1389   af_latin2_hints_compute_blue_edges( AF_GlyphHints    hints,
   1390                                       AF_LatinMetrics  metrics )
   1391   {
   1392     AF_AxisHints  axis       = &hints->axis[AF_DIMENSION_VERT];
   1393     AF_Edge       edge       = axis->edges;
   1394     AF_Edge       edge_limit = edge + axis->num_edges;
   1395     AF_LatinAxis  latin      = &metrics->axis[AF_DIMENSION_VERT];
   1396     FT_Fixed      scale      = latin->scale;
   1397     FT_Pos        best_dist0;  /* initial threshold */
   1398 
   1399 
   1400     /* compute the initial threshold as a fraction of the EM size */
   1401     best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale );
   1402 
   1403     if ( best_dist0 > 64 / 2 )
   1404       best_dist0 = 64 / 2;
   1405 
   1406     /* compute which blue zones are active, i.e. have their scaled */
   1407     /* size < 3/4 pixels                                           */
   1408 
   1409     /* for each horizontal edge search the blue zone which is closest */
   1410     for ( ; edge < edge_limit; edge++ )
   1411     {
   1412       FT_Int    bb;
   1413       AF_Width  best_blue = NULL;
   1414       FT_Pos    best_dist = best_dist0;
   1415 
   1416       for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
   1417       {
   1418         AF_LatinBlue  blue = latin->blues + bb;
   1419         FT_Bool       is_top_blue, is_major_dir;
   1420 
   1421 
   1422         /* skip inactive blue zones (i.e., those that are too small) */
   1423         if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) )
   1424           continue;
   1425 
   1426         /* if it is a top zone, check for right edges -- if it is a bottom */
   1427         /* zone, check for left edges                                      */
   1428         /*                                                                 */
   1429         /* of course, that's for TrueType                                  */
   1430         is_top_blue  = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 );
   1431         is_major_dir = FT_BOOL( edge->dir == axis->major_dir );
   1432 
   1433         /* if it is a top zone, the edge must be against the major    */
   1434         /* direction; if it is a bottom zone, it must be in the major */
   1435         /* direction                                                  */
   1436         if ( is_top_blue ^ is_major_dir )
   1437         {
   1438           FT_Pos     dist;
   1439           AF_Width   compare;
   1440 
   1441 
   1442           /* if it's a rounded edge, compare it to the overshoot position */
   1443           /* if it's a flat edge, compare it to the reference position    */
   1444           if ( edge->flags & AF_EDGE_ROUND )
   1445             compare = &blue->shoot;
   1446           else
   1447             compare = &blue->ref;
   1448 
   1449           dist = edge->fpos - compare->org;
   1450           if ( dist < 0 )
   1451             dist = -dist;
   1452 
   1453           dist = FT_MulFix( dist, scale );
   1454           if ( dist < best_dist )
   1455           {
   1456             best_dist = dist;
   1457             best_blue = compare;
   1458           }
   1459 
   1460 #if 0
   1461           /* now, compare it to the overshoot position if the edge is     */
   1462           /* rounded, and if the edge is over the reference position of a */
   1463           /* top zone, or under the reference position of a bottom zone   */
   1464           if ( edge->flags & AF_EDGE_ROUND && dist != 0 )
   1465           {
   1466             FT_Bool  is_under_ref = FT_BOOL( edge->fpos < blue->ref.org );
   1467 
   1468 
   1469             if ( is_top_blue ^ is_under_ref )
   1470             {
   1471               blue = latin->blues + bb;
   1472               dist = edge->fpos - blue->shoot.org;
   1473               if ( dist < 0 )
   1474                 dist = -dist;
   1475 
   1476               dist = FT_MulFix( dist, scale );
   1477               if ( dist < best_dist )
   1478               {
   1479                 best_dist = dist;
   1480                 best_blue = & blue->shoot;
   1481               }
   1482             }
   1483           }
   1484 #endif
   1485         }
   1486       }
   1487 
   1488       if ( best_blue )
   1489         edge->blue_edge = best_blue;
   1490     }
   1491   }
   1492 
   1493 
   1494   static FT_Error
   1495   af_latin2_hints_init( AF_GlyphHints    hints,
   1496                         AF_LatinMetrics  metrics )
   1497   {
   1498     FT_Render_Mode  mode;
   1499     FT_UInt32       scaler_flags, other_flags;
   1500     FT_Face         face = metrics->root.scaler.face;
   1501 
   1502 
   1503     af_glyph_hints_rescale( hints, (AF_ScriptMetrics)metrics );
   1504 
   1505     /*
   1506      *  correct x_scale and y_scale if needed, since they may have
   1507      *  been modified `af_latin2_metrics_scale_dim' above
   1508      */
   1509     hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale;
   1510     hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta;
   1511     hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale;
   1512     hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta;
   1513 
   1514     /* compute flags depending on render mode, etc. */
   1515     mode = metrics->root.scaler.render_mode;
   1516 
   1517 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */
   1518     if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V )
   1519     {
   1520       metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL;
   1521     }
   1522 #endif
   1523 
   1524     scaler_flags = hints->scaler_flags;
   1525     other_flags  = 0;
   1526 
   1527     /*
   1528      *  We snap the width of vertical stems for the monochrome and
   1529      *  horizontal LCD rendering targets only.
   1530      */
   1531     if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD )
   1532       other_flags |= AF_LATIN_HINTS_HORZ_SNAP;
   1533 
   1534     /*
   1535      *  We snap the width of horizontal stems for the monochrome and
   1536      *  vertical LCD rendering targets only.
   1537      */
   1538     if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V )
   1539       other_flags |= AF_LATIN_HINTS_VERT_SNAP;
   1540 
   1541     /*
   1542      *  We adjust stems to full pixels only if we don't use the `light' mode.
   1543      */
   1544     if ( mode != FT_RENDER_MODE_LIGHT )
   1545       other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
   1546 
   1547     if ( mode == FT_RENDER_MODE_MONO )
   1548       other_flags |= AF_LATIN_HINTS_MONO;
   1549 
   1550     /*
   1551      *  In `light' hinting mode we disable horizontal hinting completely.
   1552      *  We also do it if the face is italic.
   1553      */
   1554     if ( mode == FT_RENDER_MODE_LIGHT                      ||
   1555          ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 )
   1556       scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL;
   1557 
   1558     hints->scaler_flags = scaler_flags;
   1559     hints->other_flags  = other_flags;
   1560 
   1561     return 0;
   1562   }
   1563 
   1564 
   1565   /*************************************************************************/
   1566   /*************************************************************************/
   1567   /*****                                                               *****/
   1568   /*****        L A T I N   G L Y P H   G R I D - F I T T I N G        *****/
   1569   /*****                                                               *****/
   1570   /*************************************************************************/
   1571   /*************************************************************************/
   1572 
   1573   /* snap a given width in scaled coordinates to one of the */
   1574   /* current standard widths                                */
   1575 
   1576   static FT_Pos
   1577   af_latin2_snap_width( AF_Width  widths,
   1578                         FT_Int    count,
   1579                         FT_Pos    width )
   1580   {
   1581     int     n;
   1582     FT_Pos  best      = 64 + 32 + 2;
   1583     FT_Pos  reference = width;
   1584     FT_Pos  scaled;
   1585 
   1586 
   1587     for ( n = 0; n < count; n++ )
   1588     {
   1589       FT_Pos  w;
   1590       FT_Pos  dist;
   1591 
   1592 
   1593       w = widths[n].cur;
   1594       dist = width - w;
   1595       if ( dist < 0 )
   1596         dist = -dist;
   1597       if ( dist < best )
   1598       {
   1599         best      = dist;
   1600         reference = w;
   1601       }
   1602     }
   1603 
   1604     scaled = FT_PIX_ROUND( reference );
   1605 
   1606     if ( width >= reference )
   1607     {
   1608       if ( width < scaled + 48 )
   1609         width = reference;
   1610     }
   1611     else
   1612     {
   1613       if ( width > scaled - 48 )
   1614         width = reference;
   1615     }
   1616 
   1617     return width;
   1618   }
   1619 
   1620 
   1621   /* compute the snapped width of a given stem */
   1622 
   1623   static FT_Pos
   1624   af_latin2_compute_stem_width( AF_GlyphHints  hints,
   1625                                 AF_Dimension   dim,
   1626                                 FT_Pos         width,
   1627                                 AF_Edge_Flags  base_flags,
   1628                                 AF_Edge_Flags  stem_flags )
   1629   {
   1630     AF_LatinMetrics  metrics  = (AF_LatinMetrics) hints->metrics;
   1631     AF_LatinAxis     axis     = & metrics->axis[dim];
   1632     FT_Pos           dist     = width;
   1633     FT_Int           sign     = 0;
   1634     FT_Int           vertical = ( dim == AF_DIMENSION_VERT );
   1635 
   1636     FT_UNUSED( base_flags );
   1637 
   1638 
   1639     if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ||
   1640           axis->extra_light                      )
   1641       return width;
   1642 
   1643     if ( dist < 0 )
   1644     {
   1645       dist = -width;
   1646       sign = 1;
   1647     }
   1648 
   1649     if ( (  vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ||
   1650          ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) )
   1651     {
   1652       /* smooth hinting process: very lightly quantize the stem width */
   1653 
   1654       /* leave the widths of serifs alone */
   1655 
   1656       if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) )
   1657         goto Done_Width;
   1658 
   1659 #if 0
   1660       else if ( ( base_flags & AF_EDGE_ROUND ) )
   1661       {
   1662         if ( dist < 80 )
   1663           dist = 64;
   1664       }
   1665       else if ( dist < 56 )
   1666         dist = 56;
   1667 #endif
   1668       if ( axis->width_count > 0 )
   1669       {
   1670         FT_Pos  delta;
   1671 
   1672 
   1673         /* compare to standard width */
   1674         if ( axis->width_count > 0 )
   1675         {
   1676           delta = dist - axis->widths[0].cur;
   1677 
   1678           if ( delta < 0 )
   1679             delta = -delta;
   1680 
   1681           if ( delta < 40 )
   1682           {
   1683             dist = axis->widths[0].cur;
   1684             if ( dist < 48 )
   1685               dist = 48;
   1686 
   1687             goto Done_Width;
   1688           }
   1689         }
   1690 
   1691         if ( dist < 3 * 64 )
   1692         {
   1693           delta  = dist & 63;
   1694           dist  &= -64;
   1695 
   1696           if ( delta < 10 )
   1697             dist += delta;
   1698 
   1699           else if ( delta < 32 )
   1700             dist += 10;
   1701 
   1702           else if ( delta < 54 )
   1703             dist += 54;
   1704 
   1705           else
   1706             dist += delta;
   1707         }
   1708         else
   1709           dist = ( dist + 32 ) & ~63;
   1710       }
   1711     }
   1712     else
   1713     {
   1714       /* strong hinting process: snap the stem width to integer pixels */
   1715       FT_Pos  org_dist = dist;
   1716 
   1717 
   1718       dist = af_latin2_snap_width( axis->widths, axis->width_count, dist );
   1719 
   1720       if ( vertical )
   1721       {
   1722         /* in the case of vertical hinting, always round */
   1723         /* the stem heights to integer pixels            */
   1724 
   1725         if ( dist >= 64 )
   1726           dist = ( dist + 16 ) & ~63;
   1727         else
   1728           dist = 64;
   1729       }
   1730       else
   1731       {
   1732         if ( AF_LATIN_HINTS_DO_MONO( hints ) )
   1733         {
   1734           /* monochrome horizontal hinting: snap widths to integer pixels */
   1735           /* with a different threshold                                   */
   1736 
   1737           if ( dist < 64 )
   1738             dist = 64;
   1739           else
   1740             dist = ( dist + 32 ) & ~63;
   1741         }
   1742         else
   1743         {
   1744           /* for horizontal anti-aliased hinting, we adopt a more subtle */
   1745           /* approach: we strengthen small stems, round stems whose size */
   1746           /* is between 1 and 2 pixels to an integer, otherwise nothing  */
   1747 
   1748           if ( dist < 48 )
   1749             dist = ( dist + 64 ) >> 1;
   1750 
   1751           else if ( dist < 128 )
   1752           {
   1753             /* We only round to an integer width if the corresponding */
   1754             /* distortion is less than 1/4 pixel.  Otherwise this     */
   1755             /* makes everything worse since the diagonals, which are  */
   1756             /* not hinted, appear a lot bolder or thinner than the    */
   1757             /* vertical stems.                                        */
   1758 
   1759             FT_Int  delta;
   1760 
   1761 
   1762             dist = ( dist + 22 ) & ~63;
   1763             delta = dist - org_dist;
   1764             if ( delta < 0 )
   1765               delta = -delta;
   1766 
   1767             if ( delta >= 16 )
   1768             {
   1769               dist = org_dist;
   1770               if ( dist < 48 )
   1771                 dist = ( dist + 64 ) >> 1;
   1772             }
   1773           }
   1774           else
   1775             /* round otherwise to prevent color fringes in LCD mode */
   1776             dist = ( dist + 32 ) & ~63;
   1777         }
   1778       }
   1779     }
   1780 
   1781   Done_Width:
   1782     if ( sign )
   1783       dist = -dist;
   1784 
   1785     return dist;
   1786   }
   1787 
   1788 
   1789   /* align one stem edge relative to the previous stem edge */
   1790 
   1791   static void
   1792   af_latin2_align_linked_edge( AF_GlyphHints  hints,
   1793                                AF_Dimension   dim,
   1794                                AF_Edge        base_edge,
   1795                                AF_Edge        stem_edge )
   1796   {
   1797     FT_Pos  dist = stem_edge->opos - base_edge->opos;
   1798 
   1799     FT_Pos  fitted_width = af_latin2_compute_stem_width(
   1800                              hints, dim, dist,
   1801                              (AF_Edge_Flags)base_edge->flags,
   1802                              (AF_Edge_Flags)stem_edge->flags );
   1803 
   1804 
   1805     stem_edge->pos = base_edge->pos + fitted_width;
   1806 
   1807     FT_TRACE5(( "LINK: edge %d (opos=%.2f) linked to (%.2f), "
   1808                 "dist was %.2f, now %.2f\n",
   1809                 stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0,
   1810                 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 ));
   1811   }
   1812 
   1813 
   1814   static void
   1815   af_latin2_align_serif_edge( AF_GlyphHints  hints,
   1816                               AF_Edge        base,
   1817                               AF_Edge        serif )
   1818   {
   1819     FT_UNUSED( hints );
   1820 
   1821     serif->pos = base->pos + ( serif->opos - base->opos );
   1822   }
   1823 
   1824 
   1825   /*************************************************************************/
   1826   /*************************************************************************/
   1827   /*************************************************************************/
   1828   /****                                                                 ****/
   1829   /****                    E D G E   H I N T I N G                      ****/
   1830   /****                                                                 ****/
   1831   /*************************************************************************/
   1832   /*************************************************************************/
   1833   /*************************************************************************/
   1834 
   1835 
   1836   FT_LOCAL_DEF( void )
   1837   af_latin2_hint_edges( AF_GlyphHints  hints,
   1838                         AF_Dimension   dim )
   1839   {
   1840     AF_AxisHints  axis       = &hints->axis[dim];
   1841     AF_Edge       edges      = axis->edges;
   1842     AF_Edge       edge_limit = edges + axis->num_edges;
   1843     AF_Edge       edge;
   1844     AF_Edge       anchor     = 0;
   1845     FT_Int        has_serifs = 0;
   1846     FT_Pos        anchor_drift = 0;
   1847 
   1848 
   1849 
   1850     FT_TRACE5(( "==== hinting %s edges =====\n",
   1851                 dim == AF_DIMENSION_HORZ ? "vertical" : "horizontal" ));
   1852 
   1853     /* we begin by aligning all stems relative to the blue zone */
   1854     /* if needed -- that's only for horizontal edges            */
   1855 
   1856     if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) )
   1857     {
   1858       for ( edge = edges; edge < edge_limit; edge++ )
   1859       {
   1860         AF_Width  blue;
   1861         AF_Edge   edge1, edge2;
   1862 
   1863 
   1864         if ( edge->flags & AF_EDGE_DONE )
   1865           continue;
   1866 
   1867         blue  = edge->blue_edge;
   1868         edge1 = NULL;
   1869         edge2 = edge->link;
   1870 
   1871         if ( blue )
   1872         {
   1873           edge1 = edge;
   1874         }
   1875         else if ( edge2 && edge2->blue_edge )
   1876         {
   1877           blue  = edge2->blue_edge;
   1878           edge1 = edge2;
   1879           edge2 = edge;
   1880         }
   1881 
   1882         if ( !edge1 )
   1883           continue;
   1884 
   1885         FT_TRACE5(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), "
   1886                     "was (%.2f)\n",
   1887                     edge1-edges, edge1->opos / 64.0, blue->fit / 64.0,
   1888                     edge1->pos / 64.0 ));
   1889 
   1890         edge1->pos    = blue->fit;
   1891         edge1->flags |= AF_EDGE_DONE;
   1892 
   1893         if ( edge2 && !edge2->blue_edge )
   1894         {
   1895           af_latin2_align_linked_edge( hints, dim, edge1, edge2 );
   1896           edge2->flags |= AF_EDGE_DONE;
   1897         }
   1898 
   1899         if ( !anchor )
   1900         {
   1901           anchor = edge;
   1902 
   1903           anchor_drift = ( anchor->pos - anchor->opos );
   1904           if ( edge2 )
   1905             anchor_drift = ( anchor_drift +
   1906                              ( edge2->pos - edge2->opos ) ) >> 1;
   1907         }
   1908       }
   1909     }
   1910 
   1911     /* now we will align all stem edges, trying to maintain the */
   1912     /* relative order of stems in the glyph                     */
   1913     for ( edge = edges; edge < edge_limit; edge++ )
   1914     {
   1915       AF_Edge  edge2;
   1916 
   1917 
   1918       if ( edge->flags & AF_EDGE_DONE )
   1919         continue;
   1920 
   1921       /* skip all non-stem edges */
   1922       edge2 = edge->link;
   1923       if ( !edge2 )
   1924       {
   1925         has_serifs++;
   1926         continue;
   1927       }
   1928 
   1929       /* now align the stem */
   1930 
   1931       /* this should not happen, but it's better to be safe */
   1932       if ( edge2->blue_edge )
   1933       {
   1934         FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges ));
   1935 
   1936         af_latin2_align_linked_edge( hints, dim, edge2, edge );
   1937         edge->flags |= AF_EDGE_DONE;
   1938         continue;
   1939       }
   1940 
   1941       if ( !anchor )
   1942       {
   1943         FT_Pos  org_len, org_center, cur_len;
   1944         FT_Pos  cur_pos1, error1, error2, u_off, d_off;
   1945 
   1946 
   1947         org_len = edge2->opos - edge->opos;
   1948         cur_len = af_latin2_compute_stem_width(
   1949                     hints, dim, org_len,
   1950                     (AF_Edge_Flags)edge->flags,
   1951                     (AF_Edge_Flags)edge2->flags );
   1952         if ( cur_len <= 64 )
   1953           u_off = d_off = 32;
   1954         else
   1955         {
   1956           u_off = 38;
   1957           d_off = 26;
   1958         }
   1959 
   1960         if ( cur_len < 96 )
   1961         {
   1962           org_center = edge->opos + ( org_len >> 1 );
   1963 
   1964           cur_pos1   = FT_PIX_ROUND( org_center );
   1965 
   1966           error1 = org_center - ( cur_pos1 - u_off );
   1967           if ( error1 < 0 )
   1968             error1 = -error1;
   1969 
   1970           error2 = org_center - ( cur_pos1 + d_off );
   1971           if ( error2 < 0 )
   1972             error2 = -error2;
   1973 
   1974           if ( error1 < error2 )
   1975             cur_pos1 -= u_off;
   1976           else
   1977             cur_pos1 += d_off;
   1978 
   1979           edge->pos  = cur_pos1 - cur_len / 2;
   1980           edge2->pos = edge->pos + cur_len;
   1981         }
   1982         else
   1983           edge->pos = FT_PIX_ROUND( edge->opos );
   1984 
   1985         FT_TRACE5(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)"
   1986                     " snapped to (%.2f) (%.2f)\n",
   1987                     edge-edges, edge->opos / 64.0,
   1988                     edge2-edges, edge2->opos / 64.0,
   1989                     edge->pos / 64.0, edge2->pos / 64.0 ));
   1990         anchor = edge;
   1991 
   1992         edge->flags |= AF_EDGE_DONE;
   1993 
   1994         af_latin2_align_linked_edge( hints, dim, edge, edge2 );
   1995 
   1996         edge2->flags |= AF_EDGE_DONE;
   1997 
   1998         anchor_drift = ( ( anchor->pos - anchor->opos ) +
   1999                          ( edge2->pos - edge2->opos ) ) >> 1;
   2000 
   2001         FT_TRACE5(( "DRIFT: %.2f\n", anchor_drift/64.0 ));
   2002       }
   2003       else
   2004       {
   2005         FT_Pos   org_pos, org_len, org_center, cur_center, cur_len;
   2006         FT_Pos   org_left, org_right;
   2007 
   2008 
   2009         org_pos    = edge->opos + anchor_drift;
   2010         org_len    = edge2->opos - edge->opos;
   2011         org_center = org_pos + ( org_len >> 1 );
   2012 
   2013         cur_len = af_latin2_compute_stem_width(
   2014                    hints, dim, org_len,
   2015                    (AF_Edge_Flags)edge->flags,
   2016                    (AF_Edge_Flags)edge2->flags );
   2017 
   2018         org_left  = org_pos + ( ( org_len - cur_len ) >> 1 );
   2019         org_right = org_pos + ( ( org_len + cur_len ) >> 1 );
   2020 
   2021         FT_TRACE5(( "ALIGN: left=%.2f right=%.2f ",
   2022                     org_left / 64.0, org_right / 64.0 ));
   2023         cur_center = org_center;
   2024 
   2025         if ( edge2->flags & AF_EDGE_DONE )
   2026         {
   2027           FT_TRACE5(( "\n" ));
   2028           edge->pos = edge2->pos - cur_len;
   2029         }
   2030         else
   2031         {
   2032          /* we want to compare several displacement, and choose
   2033           * the one that increases fitness while minimizing
   2034           * distortion as well
   2035           */
   2036           FT_Pos   displacements[6], scores[6], org, fit, delta;
   2037           FT_UInt  count = 0;
   2038 
   2039           /* note: don't even try to fit tiny stems */
   2040           if ( cur_len < 32 )
   2041           {
   2042             FT_TRACE5(( "tiny stem\n" ));
   2043             goto AlignStem;
   2044           }
   2045 
   2046           /* if the span is within a single pixel, don't touch it */
   2047           if ( FT_PIX_FLOOR( org_left ) == FT_PIX_CEIL( org_right ) )
   2048           {
   2049             FT_TRACE5(( "single pixel stem\n" ));
   2050             goto AlignStem;
   2051           }
   2052 
   2053           if ( cur_len <= 96 )
   2054           {
   2055            /* we want to avoid the absolute worst case which is
   2056             * when the left and right edges of the span each represent
   2057             * about 50% of the gray. we'd better want to change this
   2058             * to 25/75%, since this is much more pleasant to the eye with
   2059             * very acceptable distortion
   2060             */
   2061             FT_Pos  frac_left  = org_left  & 63;
   2062             FT_Pos  frac_right = org_right & 63;
   2063 
   2064             if ( frac_left  >= 22 && frac_left  <= 42 &&
   2065                  frac_right >= 22 && frac_right <= 42 )
   2066             {
   2067               org = frac_left;
   2068               fit = ( org <= 32 ) ? 16 : 48;
   2069               delta = FT_ABS( fit - org );
   2070               displacements[count] = fit - org;
   2071               scores[count++]      = delta;
   2072               FT_TRACE5(( "dispA=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
   2073 
   2074               org = frac_right;
   2075               fit = ( org <= 32 ) ? 16 : 48;
   2076               delta = FT_ABS( fit - org );
   2077               displacements[count] = fit - org;
   2078               scores[count++]     = delta;
   2079               FT_TRACE5(( "dispB=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
   2080             }
   2081           }
   2082 
   2083           /* snapping the left edge to the grid */
   2084           org   = org_left;
   2085           fit   = FT_PIX_ROUND( org );
   2086           delta = FT_ABS( fit - org );
   2087           displacements[count] = fit - org;
   2088           scores[count++]      = delta;
   2089           FT_TRACE5(( "dispC=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
   2090 
   2091           /* snapping the right edge to the grid */
   2092           org   = org_right;
   2093           fit   = FT_PIX_ROUND( org );
   2094           delta = FT_ABS( fit - org );
   2095           displacements[count] = fit - org;
   2096           scores[count++]      = delta;
   2097           FT_TRACE5(( "dispD=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
   2098 
   2099           /* now find the best displacement */
   2100           {
   2101             FT_Pos  best_score = scores[0];
   2102             FT_Pos  best_disp  = displacements[0];
   2103             FT_UInt nn;
   2104 
   2105             for ( nn = 1; nn < count; nn++ )
   2106             {
   2107               if ( scores[nn] < best_score )
   2108               {
   2109                 best_score = scores[nn];
   2110                 best_disp  = displacements[nn];
   2111               }
   2112             }
   2113 
   2114             cur_center = org_center + best_disp;
   2115           }
   2116           FT_TRACE5(( "\n" ));
   2117         }
   2118 
   2119       AlignStem:
   2120         edge->pos  = cur_center - ( cur_len >> 1 );
   2121         edge2->pos = edge->pos + cur_len;
   2122 
   2123         FT_TRACE5(( "STEM1: %d (opos=%.2f) to %d (opos=%.2f)"
   2124                     " snapped to (%.2f) and (%.2f),"
   2125                     " org_len=%.2f cur_len=%.2f\n",
   2126                     edge-edges, edge->opos / 64.0,
   2127                     edge2-edges, edge2->opos / 64.0,
   2128                     edge->pos / 64.0, edge2->pos / 64.0,
   2129                     org_len / 64.0, cur_len / 64.0 ));
   2130 
   2131         edge->flags  |= AF_EDGE_DONE;
   2132         edge2->flags |= AF_EDGE_DONE;
   2133 
   2134         if ( edge > edges && edge->pos < edge[-1].pos )
   2135         {
   2136           FT_TRACE5(( "BOUND: %d (pos=%.2f) to (%.2f)\n",
   2137                       edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
   2138           edge->pos = edge[-1].pos;
   2139         }
   2140       }
   2141     }
   2142 
   2143     /* make sure that lowercase m's maintain their symmetry */
   2144 
   2145     /* In general, lowercase m's have six vertical edges if they are sans */
   2146     /* serif, or twelve if they are with serifs.  This implementation is  */
   2147     /* based on that assumption, and seems to work very well with most    */
   2148     /* faces.  However, if for a certain face this assumption is not      */
   2149     /* true, the m is just rendered like before.  In addition, any stem   */
   2150     /* correction will only be applied to symmetrical glyphs (even if the */
   2151     /* glyph is not an m), so the potential for unwanted distortion is    */
   2152     /* relatively low.                                                    */
   2153 
   2154     /* We don't handle horizontal edges since we can't easily assure that */
   2155     /* the third (lowest) stem aligns with the base line; it might end up */
   2156     /* one pixel higher or lower.                                         */
   2157 
   2158 #if 0
   2159     {
   2160       FT_Int  n_edges = edge_limit - edges;
   2161 
   2162 
   2163       if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) )
   2164       {
   2165         AF_Edge  edge1, edge2, edge3;
   2166         FT_Pos   dist1, dist2, span, delta;
   2167 
   2168 
   2169         if ( n_edges == 6 )
   2170         {
   2171           edge1 = edges;
   2172           edge2 = edges + 2;
   2173           edge3 = edges + 4;
   2174         }
   2175         else
   2176         {
   2177           edge1 = edges + 1;
   2178           edge2 = edges + 5;
   2179           edge3 = edges + 9;
   2180         }
   2181 
   2182         dist1 = edge2->opos - edge1->opos;
   2183         dist2 = edge3->opos - edge2->opos;
   2184 
   2185         span = dist1 - dist2;
   2186         if ( span < 0 )
   2187           span = -span;
   2188 
   2189         if ( span < 8 )
   2190         {
   2191           delta = edge3->pos - ( 2 * edge2->pos - edge1->pos );
   2192           edge3->pos -= delta;
   2193           if ( edge3->link )
   2194             edge3->link->pos -= delta;
   2195 
   2196           /* move the serifs along with the stem */
   2197           if ( n_edges == 12 )
   2198           {
   2199             ( edges + 8 )->pos -= delta;
   2200             ( edges + 11 )->pos -= delta;
   2201           }
   2202 
   2203           edge3->flags |= AF_EDGE_DONE;
   2204           if ( edge3->link )
   2205             edge3->link->flags |= AF_EDGE_DONE;
   2206         }
   2207       }
   2208     }
   2209 #endif
   2210 
   2211     if ( has_serifs || !anchor )
   2212     {
   2213       /*
   2214        *  now hint the remaining edges (serifs and single) in order
   2215        *  to complete our processing
   2216        */
   2217       for ( edge = edges; edge < edge_limit; edge++ )
   2218       {
   2219         FT_Pos  delta;
   2220 
   2221 
   2222         if ( edge->flags & AF_EDGE_DONE )
   2223           continue;
   2224 
   2225         delta = 1000;
   2226 
   2227         if ( edge->serif )
   2228         {
   2229           delta = edge->serif->opos - edge->opos;
   2230           if ( delta < 0 )
   2231             delta = -delta;
   2232         }
   2233 
   2234         if ( delta < 64 + 16 )
   2235         {
   2236           af_latin2_align_serif_edge( hints, edge->serif, edge );
   2237           FT_TRACE5(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)"
   2238                       " aligned to (%.2f)\n",
   2239                       edge-edges, edge->opos / 64.0,
   2240                       edge->serif - edges, edge->serif->opos / 64.0,
   2241                       edge->pos / 64.0 ));
   2242         }
   2243         else if ( !anchor )
   2244         {
   2245           FT_TRACE5(( "SERIF_ANCHOR: edge %d (opos=%.2f)"
   2246                       " snapped to (%.2f)\n",
   2247                       edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
   2248           edge->pos = FT_PIX_ROUND( edge->opos );
   2249           anchor    = edge;
   2250         }
   2251         else
   2252         {
   2253           AF_Edge  before, after;
   2254 
   2255 
   2256           for ( before = edge - 1; before >= edges; before-- )
   2257             if ( before->flags & AF_EDGE_DONE )
   2258               break;
   2259 
   2260           for ( after = edge + 1; after < edge_limit; after++ )
   2261             if ( after->flags & AF_EDGE_DONE )
   2262               break;
   2263 
   2264           if ( before >= edges && before < edge   &&
   2265                after < edge_limit && after > edge )
   2266           {
   2267             if ( after->opos == before->opos )
   2268               edge->pos = before->pos;
   2269             else
   2270               edge->pos = before->pos +
   2271                           FT_MulDiv( edge->opos - before->opos,
   2272                                      after->pos - before->pos,
   2273                                      after->opos - before->opos );
   2274             FT_TRACE5(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)"
   2275                         " from %d (opos=%.2f)\n",
   2276                         edge-edges, edge->opos / 64.0, edge->pos / 64.0,
   2277                         before - edges, before->opos / 64.0 ));
   2278           }
   2279           else
   2280           {
   2281             edge->pos = anchor->pos +
   2282                         ( ( edge->opos - anchor->opos + 16 ) & ~31 );
   2283 
   2284             FT_TRACE5(( "SERIF_LINK2: edge %d (opos=%.2f)"
   2285                         " snapped to (%.2f)\n",
   2286                         edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
   2287           }
   2288         }
   2289 
   2290         edge->flags |= AF_EDGE_DONE;
   2291 
   2292         if ( edge > edges && edge->pos < edge[-1].pos )
   2293           edge->pos = edge[-1].pos;
   2294 
   2295         if ( edge + 1 < edge_limit        &&
   2296              edge[1].flags & AF_EDGE_DONE &&
   2297              edge->pos > edge[1].pos      )
   2298           edge->pos = edge[1].pos;
   2299       }
   2300     }
   2301   }
   2302 
   2303 
   2304   static FT_Error
   2305   af_latin2_hints_apply( AF_GlyphHints    hints,
   2306                          FT_Outline*      outline,
   2307                          AF_LatinMetrics  metrics )
   2308   {
   2309     FT_Error  error;
   2310     int       dim;
   2311 
   2312 
   2313     error = af_glyph_hints_reload( hints, outline );
   2314     if ( error )
   2315       goto Exit;
   2316 
   2317     /* analyze glyph outline */
   2318 #ifdef AF_CONFIG_OPTION_USE_WARPER
   2319     if ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT ||
   2320          AF_HINTS_DO_HORIZONTAL( hints ) )
   2321 #else
   2322     if ( AF_HINTS_DO_HORIZONTAL( hints ) )
   2323 #endif
   2324     {
   2325       error = af_latin2_hints_detect_features( hints, AF_DIMENSION_HORZ );
   2326       if ( error )
   2327         goto Exit;
   2328     }
   2329 
   2330     if ( AF_HINTS_DO_VERTICAL( hints ) )
   2331     {
   2332       error = af_latin2_hints_detect_features( hints, AF_DIMENSION_VERT );
   2333       if ( error )
   2334         goto Exit;
   2335 
   2336       af_latin2_hints_compute_blue_edges( hints, metrics );
   2337     }
   2338 
   2339     /* grid-fit the outline */
   2340     for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
   2341     {
   2342 #ifdef AF_CONFIG_OPTION_USE_WARPER
   2343       if ( ( dim == AF_DIMENSION_HORZ &&
   2344              metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT ) )
   2345       {
   2346         AF_WarperRec  warper;
   2347         FT_Fixed      scale;
   2348         FT_Pos        delta;
   2349 
   2350 
   2351         af_warper_compute( &warper, hints, dim, &scale, &delta );
   2352         af_glyph_hints_scale_dim( hints, dim, scale, delta );
   2353         continue;
   2354       }
   2355 #endif
   2356 
   2357       if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
   2358            ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) )   )
   2359       {
   2360         af_latin2_hint_edges( hints, (AF_Dimension)dim );
   2361         af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim );
   2362         af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
   2363         af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim );
   2364       }
   2365     }
   2366     af_glyph_hints_save( hints, outline );
   2367 
   2368   Exit:
   2369     return error;
   2370   }
   2371 
   2372 
   2373   /*************************************************************************/
   2374   /*************************************************************************/
   2375   /*****                                                               *****/
   2376   /*****              L A T I N   S C R I P T   C L A S S              *****/
   2377   /*****                                                               *****/
   2378   /*************************************************************************/
   2379   /*************************************************************************/
   2380 
   2381 
   2382   static const AF_Script_UniRangeRec  af_latin2_uniranges[] =
   2383   {
   2384     AF_UNIRANGE_REC( 32UL,  127UL ),    /* TODO: Add new Unicode ranges here! */
   2385     AF_UNIRANGE_REC( 160UL, 255UL ),
   2386     AF_UNIRANGE_REC( 0UL,   0UL )
   2387   };
   2388 
   2389 
   2390   AF_DEFINE_SCRIPT_CLASS( af_latin2_script_class,
   2391     AF_SCRIPT_LATIN2,
   2392     af_latin2_uniranges,
   2393     'o',
   2394 
   2395     sizeof ( AF_LatinMetricsRec ),
   2396 
   2397     (AF_Script_InitMetricsFunc) af_latin2_metrics_init,
   2398     (AF_Script_ScaleMetricsFunc)af_latin2_metrics_scale,
   2399     (AF_Script_DoneMetricsFunc) NULL,
   2400 
   2401     (AF_Script_InitHintsFunc)   af_latin2_hints_init,
   2402     (AF_Script_ApplyHintsFunc)  af_latin2_hints_apply
   2403   )
   2404 
   2405 
   2406 /* END */
   2407