kc3-lang/freetype/src/autofit/aflatin2.c

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• Hash : a0dd16fb
  Author :
  Date : 2018-08-15T18:13:17
  

  Don't use `trace_' prefix for FT_COMPONENT arguments. * include/freetype/internal/ftdebug.h (FT_TRACE_COMP, FT_TRACE_COMP_): New auxiliary macros to add `trace_' prefix. (FT_TRACE): Use `FT_TRACE_COMP'. */* (FT_COMPONENT): Updated.

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• src/autofit/aflatin2.c

• /* ATTENTION: This file doesn't compile.  It is only here as a reference */
  /*            of an alternative latin hinting algorithm that was always  */
  /*            marked as experimental.                                    */
  
  
  /****************************************************************************
   *
   * aflatin2.c
   *
   *   Auto-fitter hinting routines for latin writing system (body).
   *
   * Copyright 2003-2018 by
   * David Turner, Robert Wilhelm, and Werner Lemberg.
   *
   * This file is part of the FreeType project, and may only be used,
   * modified, and distributed under the terms of the FreeType project
   * license, LICENSE.TXT.  By continuing to use, modify, or distribute
   * this file you indicate that you have read the license and
   * understand and accept it fully.
   *
   */
  
  
  #include FT_ADVANCES_H
  
  
  #ifdef FT_OPTION_AUTOFIT2
  
  #include "afglobal.h"
  #include "aflatin.h"
  #include "aflatin2.h"
  #include "aferrors.h"
  
  
  #ifdef AF_CONFIG_OPTION_USE_WARPER
  #include "afwarp.h"
  #endif
  
  
    /**************************************************************************
     *
     * The macro FT_COMPONENT is used in trace mode.  It is an implicit
     * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
     * messages during execution.
     */
  #undef  FT_COMPONENT
  #define FT_COMPONENT  aflatin2
  
  
    FT_LOCAL_DEF( FT_Error )
    af_latin2_hints_compute_segments( AF_GlyphHints  hints,
                                      AF_Dimension   dim );
  
    FT_LOCAL_DEF( void )
    af_latin2_hints_link_segments( AF_GlyphHints  hints,
                                   AF_Dimension   dim );
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****            L A T I N   G L O B A L   M E T R I C S            *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    FT_LOCAL_DEF( void )
    af_latin2_metrics_init_widths( AF_LatinMetrics  metrics,
                                   FT_Face          face )
    {
      /* scan the array of segments in each direction */
      AF_GlyphHintsRec  hints[1];
  
  
      af_glyph_hints_init( hints, face->memory );
  
      metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
      metrics->axis[AF_DIMENSION_VERT].width_count = 0;
  
      {
        FT_Error             error;
        FT_UInt              glyph_index;
        int                  dim;
        AF_LatinMetricsRec   dummy[1];
        AF_Scaler            scaler = &dummy->root.scaler;
  
  
        glyph_index = FT_Get_Char_Index(
                        face,
                        metrics->root.style_class->standard_char );
        if ( glyph_index == 0 )
          goto Exit;
  
        error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
        if ( error || face->glyph->outline.n_points <= 0 )
          goto Exit;
  
        FT_ZERO( dummy );
  
        dummy->units_per_em = metrics->units_per_em;
        scaler->x_scale     = scaler->y_scale = 0x10000L;
        scaler->x_delta     = scaler->y_delta = 0;
        scaler->face        = face;
        scaler->render_mode = FT_RENDER_MODE_NORMAL;
        scaler->flags       = 0;
  
        af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy );
  
        error = af_glyph_hints_reload( hints, &face->glyph->outline );
        if ( error )
          goto Exit;
  
        for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
        {
          AF_LatinAxis  axis    = &metrics->axis[dim];
          AF_AxisHints  axhints = &hints->axis[dim];
          AF_Segment    seg, limit, link;
          FT_UInt       num_widths = 0;
  
  
          error = af_latin2_hints_compute_segments( hints,
                                                   (AF_Dimension)dim );
          if ( error )
            goto Exit;
  
          af_latin2_hints_link_segments( hints,
                                        (AF_Dimension)dim );
  
          seg   = axhints->segments;
          limit = seg + axhints->num_segments;
  
          for ( ; seg < limit; seg++ )
          {
            link = seg->link;
  
            /* we only consider stem segments there! */
            if ( link && link->link == seg && link > seg )
            {
              FT_Pos  dist;
  
  
              dist = seg->pos - link->pos;
              if ( dist < 0 )
                dist = -dist;
  
              if ( num_widths < AF_LATIN_MAX_WIDTHS )
                axis->widths[num_widths++].org = dist;
            }
          }
  
          af_sort_widths( num_widths, axis->widths );
          axis->width_count = num_widths;
        }
  
    Exit:
        for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
        {
          AF_LatinAxis  axis = &metrics->axis[dim];
          FT_Pos        stdw;
  
  
          stdw = ( axis->width_count > 0 )
                   ? axis->widths[0].org
                   : AF_LATIN_CONSTANT( metrics, 50 );
  
          /* let's try 20% of the smallest width */
          axis->edge_distance_threshold = stdw / 5;
          axis->standard_width          = stdw;
          axis->extra_light             = 0;
        }
      }
  
      af_glyph_hints_done( hints );
    }
  
  
  
  #define AF_LATIN_MAX_TEST_CHARACTERS  12
  
  
    static const char af_latin2_blue_chars[AF_LATIN_MAX_BLUES]
                                          [AF_LATIN_MAX_TEST_CHARACTERS+1] =
    {
      "THEZOCQS",
      "HEZLOCUS",
      "fijkdbh",
      "xzroesc",
      "xzroesc",
      "pqgjy"
    };
  
  
    static void
    af_latin2_metrics_init_blues( AF_LatinMetrics  metrics,
                                  FT_Face          face )
    {
      FT_Pos        flats [AF_LATIN_MAX_TEST_CHARACTERS];
      FT_Pos        rounds[AF_LATIN_MAX_TEST_CHARACTERS];
      FT_Int        num_flats;
      FT_Int        num_rounds;
      FT_Int        bb;
      AF_LatinBlue  blue;
      FT_Error      error;
      AF_LatinAxis  axis  = &metrics->axis[AF_DIMENSION_VERT];
      FT_GlyphSlot  glyph = face->glyph;
  
  
      /* we compute the blues simply by loading each character from the     */
      /* 'af_latin2_blue_chars[blues]' string, then compute its top-most or */
      /* bottom-most points (depending on `AF_IS_TOP_BLUE')                 */
  
      FT_TRACE5(( "blue zones computation\n"
                  "======================\n\n" ));
  
      for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
      {
        const char*  p     = af_latin2_blue_chars[bb];
        const char*  limit = p + AF_LATIN_MAX_TEST_CHARACTERS;
        FT_Pos*      blue_ref;
        FT_Pos*      blue_shoot;
  
  
        FT_TRACE5(( "blue zone %d:\n", bb ));
  
        num_flats  = 0;
        num_rounds = 0;
  
        for ( ; p < limit && *p; p++ )
        {
          FT_UInt     glyph_index;
          FT_Int      best_point, best_y, best_first, best_last;
          FT_Vector*  points;
          FT_Bool     round;
  
  
          /* load the character in the face -- skip unknown or empty ones */
          glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p );
          if ( glyph_index == 0 )
            continue;
  
          error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
          if ( error || glyph->outline.n_points <= 0 )
            continue;
  
          /* now compute min or max point indices and coordinates */
          points      = glyph->outline.points;
          best_point  = -1;
          best_y      = 0;  /* make compiler happy */
          best_first  = 0;  /* ditto */
          best_last   = 0;  /* ditto */
  
          {
            FT_Int  nn;
            FT_Int  first = 0;
            FT_Int  last  = -1;
  
  
            for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ )
            {
              FT_Int  old_best_point = best_point;
              FT_Int  pp;
  
  
              last = glyph->outline.contours[nn];
  
              /* Avoid single-point contours since they are never rasterized. */
              /* In some fonts, they correspond to mark attachment points     */
              /* which are way outside of the glyph's real outline.           */
              if ( last == first )
                  continue;
  
              if ( AF_LATIN_IS_TOP_BLUE( bb ) )
              {
                for ( pp = first; pp <= last; pp++ )
                  if ( best_point < 0 || points[pp].y > best_y )
                  {
                    best_point = pp;
                    best_y     = points[pp].y;
                  }
              }
              else
              {
                for ( pp = first; pp <= last; pp++ )
                  if ( best_point < 0 || points[pp].y < best_y )
                  {
                    best_point = pp;
                    best_y     = points[pp].y;
                  }
              }
  
              if ( best_point != old_best_point )
              {
                best_first = first;
                best_last  = last;
              }
            }
            FT_TRACE5(( "  %c  %d", *p, best_y ));
          }
  
          /* now check whether the point belongs to a straight or round   */
          /* segment; we first need to find in which contour the extremum */
          /* lies, then inspect its previous and next points              */
          {
            FT_Pos  best_x = points[best_point].x;
            FT_Int  start, end, prev, next;
            FT_Pos  dist;
  
  
            /* now look for the previous and next points that are not on the */
            /* same Y coordinate.  Threshold the `closeness'...              */
            start = end = best_point;
  
            do
            {
              prev = start - 1;
              if ( prev < best_first )
                prev = best_last;
  
              dist = FT_ABS( points[prev].y - best_y );
              /* accept a small distance or a small angle (both values are */
              /* heuristic; value 20 corresponds to approx. 2.9 degrees)   */
              if ( dist > 5 )
                if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist )
                  break;
  
              start = prev;
  
            } while ( start != best_point );
  
            do
            {
              next = end + 1;
              if ( next > best_last )
                next = best_first;
  
              dist = FT_ABS( points[next].y - best_y );
              if ( dist > 5 )
                if ( FT_ABS( points[next].x - best_x ) <= 20 * dist )
                  break;
  
              end = next;
  
            } while ( end != best_point );
  
            /* now, set the `round' flag depending on the segment's kind */
            round = FT_BOOL(
              FT_CURVE_TAG( glyph->outline.tags[start] ) != FT_CURVE_TAG_ON ||
              FT_CURVE_TAG( glyph->outline.tags[ end ] ) != FT_CURVE_TAG_ON );
  
            FT_TRACE5(( " (%s)\n", round ? "round" : "flat" ));
          }
  
          if ( round )
            rounds[num_rounds++] = best_y;
          else
            flats[num_flats++]   = best_y;
        }
  
        if ( num_flats == 0 && num_rounds == 0 )
        {
          /*
           * we couldn't find a single glyph to compute this blue zone,
           * we will simply ignore it then
           */
          FT_TRACE5(( "  empty\n" ));
          continue;
        }
  
        /* we have computed the contents of the `rounds' and `flats' tables, */
        /* now determine the reference and overshoot position of the blue -- */
        /* we simply take the median value after a simple sort               */
        af_sort_pos( num_rounds, rounds );
        af_sort_pos( num_flats,  flats );
  
        blue       = & axis->blues[axis->blue_count];
        blue_ref   = & blue->ref.org;
        blue_shoot = & blue->shoot.org;
  
        axis->blue_count++;
  
        if ( num_flats == 0 )
        {
          *blue_ref   =
          *blue_shoot = rounds[num_rounds / 2];
        }
        else if ( num_rounds == 0 )
        {
          *blue_ref   =
          *blue_shoot = flats[num_flats / 2];
        }
        else
        {
          *blue_ref   = flats[num_flats / 2];
          *blue_shoot = rounds[num_rounds / 2];
        }
  
        /* there are sometimes problems: if the overshoot position of top     */
        /* zones is under its reference position, or the opposite for bottom  */
        /* zones.  We must thus check everything there and correct the errors */
        if ( *blue_shoot != *blue_ref )
        {
          FT_Pos   ref      = *blue_ref;
          FT_Pos   shoot    = *blue_shoot;
          FT_Bool  over_ref = FT_BOOL( shoot > ref );
  
  
          if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref )
          {
            *blue_ref   =
            *blue_shoot = ( shoot + ref ) / 2;
  
            FT_TRACE5(( "  [overshoot smaller than reference,"
                        " taking mean value]\n" ));
          }
        }
  
        blue->flags = 0;
        if ( AF_LATIN_IS_TOP_BLUE( bb ) )
          blue->flags |= AF_LATIN_BLUE_TOP;
  
        /*
         * The following flag is used later to adjust the y and x scales
         * in order to optimize the pixel grid alignment of the top of small
         * letters.
         */
        if ( AF_LATIN_IS_X_HEIGHT_BLUE( bb ) )
          blue->flags |= AF_LATIN_BLUE_ADJUSTMENT;
  
        FT_TRACE5(( "    -> reference = %ld\n"
                    "       overshoot = %ld\n",
                    *blue_ref, *blue_shoot ));
      }
  
      return;
    }
  
  
    FT_LOCAL_DEF( void )
    af_latin2_metrics_check_digits( AF_LatinMetrics  metrics,
                                    FT_Face          face )
    {
      FT_UInt   i;
      FT_Bool   started = 0, same_width = 1;
      FT_Fixed  advance, old_advance = 0;
  
  
      /* check whether all ASCII digits have the same advance width; */
      /* digit `0' is 0x30 in all supported charmaps                 */
      for ( i = 0x30; i <= 0x39; i++ )
      {
        FT_UInt  glyph_index;
  
  
        glyph_index = FT_Get_Char_Index( face, i );
        if ( glyph_index == 0 )
          continue;
  
        if ( FT_Get_Advance( face, glyph_index,
                             FT_LOAD_NO_SCALE         |
                             FT_LOAD_NO_HINTING       |
                             FT_LOAD_IGNORE_TRANSFORM,
                             &advance ) )
          continue;
  
        if ( started )
        {
          if ( advance != old_advance )
          {
            same_width = 0;
            break;
          }
        }
        else
        {
          old_advance = advance;
          started     = 1;
        }
      }
  
      metrics->root.digits_have_same_width = same_width;
    }
  
  
    FT_LOCAL_DEF( FT_Error )
    af_latin2_metrics_init( AF_LatinMetrics  metrics,
                            FT_Face          face )
    {
      FT_Error    error  = FT_Err_Ok;
      FT_CharMap  oldmap = face->charmap;
      FT_UInt     ee;
  
      static const FT_Encoding  latin_encodings[] =
      {
        FT_ENCODING_UNICODE,
        FT_ENCODING_APPLE_ROMAN,
        FT_ENCODING_ADOBE_STANDARD,
        FT_ENCODING_ADOBE_LATIN_1,
        FT_ENCODING_NONE  /* end of list */
      };
  
  
      metrics->units_per_em = face->units_per_EM;
  
      /* do we have a latin charmap in there? */
      for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ )
      {
        error = FT_Select_Charmap( face, latin_encodings[ee] );
        if ( !error )
          break;
      }
  
      if ( !error )
      {
        af_latin2_metrics_init_widths( metrics, face );
        af_latin2_metrics_init_blues( metrics, face );
        af_latin2_metrics_check_digits( metrics, face );
      }
  
      FT_Set_Charmap( face, oldmap );
      return FT_Err_Ok;
    }
  
  
    static void
    af_latin2_metrics_scale_dim( AF_LatinMetrics  metrics,
                                 AF_Scaler        scaler,
                                 AF_Dimension     dim )
    {
      FT_Fixed      scale;
      FT_Pos        delta;
      AF_LatinAxis  axis;
      FT_UInt       nn;
  
  
      if ( dim == AF_DIMENSION_HORZ )
      {
        scale = scaler->x_scale;
        delta = scaler->x_delta;
      }
      else
      {
        scale = scaler->y_scale;
        delta = scaler->y_delta;
      }
  
      axis = &metrics->axis[dim];
  
      if ( axis->org_scale == scale && axis->org_delta == delta )
        return;
  
      axis->org_scale = scale;
      axis->org_delta = delta;
  
      /*
       * correct Y scale to optimize the alignment of the top of small
       * letters to the pixel grid
       */
      if ( dim == AF_DIMENSION_VERT )
      {
        AF_LatinAxis  vaxis = &metrics->axis[AF_DIMENSION_VERT];
        AF_LatinBlue  blue = NULL;
  
  
        for ( nn = 0; nn < vaxis->blue_count; nn++ )
        {
          if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT )
          {
            blue = &vaxis->blues[nn];
            break;
          }
        }
  
        if ( blue )
        {
          FT_Pos   scaled;
          FT_Pos   threshold;
          FT_Pos   fitted;
          FT_UInt  limit;
          FT_UInt  ppem;
  
  
          scaled    = FT_MulFix( blue->shoot.org, scaler->y_scale );
          ppem      = metrics->root.scaler.face->size->metrics.x_ppem;
          limit     = metrics->root.globals->increase_x_height;
          threshold = 40;
  
          /* if the `increase-x-height' property is active, */
          /* we round up much more often                    */
          if ( limit                                 &&
               ppem <= limit                         &&
               ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN )
            threshold = 52;
  
          fitted = ( scaled + threshold ) & ~63;
  
  #if 1
          if ( scaled != fitted )
          {
            scale = FT_MulDiv( scale, fitted, scaled );
            FT_TRACE5(( "== scaled x-top = %.2g"
                        "  fitted = %.2g, scaling = %.4g\n",
                        scaled / 64.0, fitted / 64.0,
                        ( fitted * 1.0 ) / scaled ));
          }
  #endif
        }
      }
  
      axis->scale = scale;
      axis->delta = delta;
  
      if ( dim == AF_DIMENSION_HORZ )
      {
        metrics->root.scaler.x_scale = scale;
        metrics->root.scaler.x_delta = delta;
      }
      else
      {
        metrics->root.scaler.y_scale = scale;
        metrics->root.scaler.y_delta = delta;
      }
  
      /* scale the standard widths */
      for ( nn = 0; nn < axis->width_count; nn++ )
      {
        AF_Width  width = axis->widths + nn;
  
  
        width->cur = FT_MulFix( width->org, scale );
        width->fit = width->cur;
      }
  
      /* an extra-light axis corresponds to a standard width that is */
      /* smaller than 5/8 pixels                                     */
      axis->extra_light =
        (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 );
  
      if ( dim == AF_DIMENSION_VERT )
      {
        /* scale the blue zones */
        for ( nn = 0; nn < axis->blue_count; nn++ )
        {
          AF_LatinBlue  blue = &axis->blues[nn];
          FT_Pos        dist;
  
  
          blue->ref.cur   = FT_MulFix( blue->ref.org, scale ) + delta;
          blue->ref.fit   = blue->ref.cur;
          blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
          blue->shoot.fit = blue->shoot.cur;
          blue->flags    &= ~AF_LATIN_BLUE_ACTIVE;
  
          /* a blue zone is only active if it is less than 3/4 pixels tall */
          dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
          if ( dist <= 48 && dist >= -48 )
          {
            FT_Pos  delta1, delta2;
  
            delta1 = blue->shoot.org - blue->ref.org;
            delta2 = delta1;
            if ( delta1 < 0 )
              delta2 = -delta2;
  
            delta2 = FT_MulFix( delta2, scale );
  
            if ( delta2 < 32 )
              delta2 = 0;
            else if ( delta2 < 64 )
              delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
            else
              delta2 = FT_PIX_ROUND( delta2 );
  
            if ( delta1 < 0 )
              delta2 = -delta2;
  
            blue->ref.fit   = FT_PIX_ROUND( blue->ref.cur );
            blue->shoot.fit = blue->ref.fit + delta2;
  
            FT_TRACE5(( ">> activating blue zone %d:"
                        "  ref.cur=%.2g ref.fit=%.2g"
                        "  shoot.cur=%.2g shoot.fit=%.2g\n",
                        nn, blue->ref.cur / 64.0, blue->ref.fit / 64.0,
                        blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 ));
  
            blue->flags |= AF_LATIN_BLUE_ACTIVE;
          }
        }
      }
    }
  
  
    FT_LOCAL_DEF( void )
    af_latin2_metrics_scale( AF_LatinMetrics  metrics,
                             AF_Scaler        scaler )
    {
      metrics->root.scaler.render_mode = scaler->render_mode;
      metrics->root.scaler.face        = scaler->face;
      metrics->root.scaler.flags       = scaler->flags;
  
      af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
      af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
    }
  
  
    /* Extract standard_width from writing system/script specific */
    /* metrics class.                                             */
  
    FT_LOCAL_DEF( void )
    af_latin2_get_standard_widths( AF_LatinMetrics  metrics,
                                   FT_Pos*          stdHW,
                                   FT_Pos*          stdVW )
    {
      if ( stdHW )
        *stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width;
  
      if ( stdVW )
        *stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****           L A T I N   G L Y P H   A N A L Y S I S             *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  #define  SORT_SEGMENTS
  
    FT_LOCAL_DEF( FT_Error )
    af_latin2_hints_compute_segments( AF_GlyphHints  hints,
                                      AF_Dimension   dim )
    {
      AF_AxisHints  axis          = &hints->axis[dim];
      FT_Memory     memory        = hints->memory;
      FT_Error      error         = FT_Err_Ok;
      AF_Segment    segment       = NULL;
      AF_SegmentRec seg0;
      AF_Point*     contour       = hints->contours;
      AF_Point*     contour_limit = contour + hints->num_contours;
      AF_Direction  major_dir, segment_dir;
  
  
      FT_ZERO( &seg0 );
      seg0.score = 32000;
      seg0.flags = AF_EDGE_NORMAL;
  
      major_dir   = (AF_Direction)FT_ABS( axis->major_dir );
      segment_dir = major_dir;
  
      axis->num_segments = 0;
  
      /* set up (u,v) in each point */
      if ( dim == AF_DIMENSION_HORZ )
      {
        AF_Point  point = hints->points;
        AF_Point  limit = point + hints->num_points;
  
  
        for ( ; point < limit; point++ )
        {
          point->u = point->fx;
          point->v = point->fy;
        }
      }
      else
      {
        AF_Point  point = hints->points;
        AF_Point  limit = point + hints->num_points;
  
  
        for ( ; point < limit; point++ )
        {
          point->u = point->fy;
          point->v = point->fx;
        }
      }
  
      /* do each contour separately */
      for ( ; contour < contour_limit; contour++ )
      {
        AF_Point  point   =  contour[0];
        AF_Point  start   =  point;
        AF_Point  last    =  point->prev;
  
  
        if ( point == last )  /* skip singletons -- just in case */
          continue;
  
        /* already on an edge ?, backtrack to find its start */
        if ( FT_ABS( point->in_dir ) == major_dir )
        {
          point = point->prev;
  
          while ( point->in_dir == start->in_dir )
            point = point->prev;
        }
        else  /* otherwise, find first segment start, if any */
        {
          while ( FT_ABS( point->out_dir ) != major_dir )
          {
            point = point->next;
  
            if ( point == start )
              goto NextContour;
          }
        }
  
        start = point;
  
        for  (;;)
        {
          AF_Point  first;
          FT_Pos    min_u, min_v, max_u, max_v;
  
          /* we're at the start of a new segment */
          FT_ASSERT( FT_ABS( point->out_dir ) == major_dir &&
                             point->in_dir != point->out_dir );
          first = point;
  
          min_u = max_u = point->u;
          min_v = max_v = point->v;
  
          point = point->next;
  
          while ( point->out_dir == first->out_dir )
          {
            point = point->next;
  
            if ( point->u < min_u )
              min_u = point->u;
  
            if ( point->u > max_u )
              max_u = point->u;
          }
  
          if ( point->v < min_v )
            min_v = point->v;
  
          if ( point->v > max_v )
            max_v = point->v;
  
          /* record new segment */
          error = af_axis_hints_new_segment( axis, memory, &segment );
          if ( error )
            goto Exit;
  
          segment[0]         = seg0;
          segment->dir       = first->out_dir;
          segment->first     = first;
          segment->last      = point;
          segment->pos       = (FT_Short)( ( min_u + max_u ) >> 1 );
          segment->min_coord = (FT_Short) min_v;
          segment->max_coord = (FT_Short) max_v;
          segment->height    = (FT_Short)( max_v - min_v );
  
          /* a segment is round if it doesn't have successive */
          /* on-curve points.                                 */
          {
            AF_Point  pt   = first;
            AF_Point  last = point;
            FT_UInt   f0   = pt->flags & AF_FLAG_CONTROL;
            FT_UInt   f1;
  
  
            segment->flags &= ~AF_EDGE_ROUND;
  
            for ( ; pt != last; f0 = f1 )
            {
              pt = pt->next;
              f1 = pt->flags & AF_FLAG_CONTROL;
  
              if ( !f0 && !f1 )
                break;
  
              if ( pt == last )
                segment->flags |= AF_EDGE_ROUND;
            }
          }
  
         /* this can happen in the case of a degenerate contour
          * e.g. a 2-point vertical contour
          */
          if ( point == start )
            break;
  
          /* jump to the start of the next segment, if any */
          while ( FT_ABS( point->out_dir ) != major_dir )
          {
            point = point->next;
  
            if ( point == start )
              goto NextContour;
          }
        }
  
      NextContour:
        ;
      } /* contours */
  
      /* now slightly increase the height of segments when this makes */
      /* sense -- this is used to better detect and ignore serifs     */
      {
        AF_Segment  segments     = axis->segments;
        AF_Segment  segments_end = segments + axis->num_segments;
  
  
        for ( segment = segments; segment < segments_end; segment++ )
        {
          AF_Point  first   = segment->first;
          AF_Point  last    = segment->last;
          AF_Point  p;
          FT_Pos    first_v = first->v;
          FT_Pos    last_v  = last->v;
  
  
          if ( first_v < last_v )
          {
            p = first->prev;
            if ( p->v < first_v )
              segment->height = (FT_Short)( segment->height +
                                            ( ( first_v - p->v ) >> 1 ) );
  
            p = last->next;
            if ( p->v > last_v )
              segment->height = (FT_Short)( segment->height +
                                            ( ( p->v - last_v ) >> 1 ) );
          }
          else
          {
            p = first->prev;
            if ( p->v > first_v )
              segment->height = (FT_Short)( segment->height +
                                            ( ( p->v - first_v ) >> 1 ) );
  
            p = last->next;
            if ( p->v < last_v )
              segment->height = (FT_Short)( segment->height +
                                            ( ( last_v - p->v ) >> 1 ) );
          }
        }
      }
  
  #ifdef AF_SORT_SEGMENTS
     /* place all segments with a negative direction to the start
      * of the array, used to speed up segment linking later...
      */
      {
        AF_Segment  segments = axis->segments;
        FT_UInt     count    = axis->num_segments;
        FT_UInt     ii, jj;
  
        for ( ii = 0; ii < count; ii++ )
        {
          if ( segments[ii].dir > 0 )
          {
            for ( jj = ii + 1; jj < count; jj++ )
            {
              if ( segments[jj].dir < 0 )
              {
                AF_SegmentRec  tmp;
  
  
                tmp          = segments[ii];
                segments[ii] = segments[jj];
                segments[jj] = tmp;
  
                break;
              }
            }
  
            if ( jj == count )
              break;
          }
        }
        axis->mid_segments = ii;
      }
  #endif
  
    Exit:
      return error;
    }
  
  
    FT_LOCAL_DEF( void )
    af_latin2_hints_link_segments( AF_GlyphHints  hints,
                                   AF_Dimension   dim )
    {
      AF_AxisHints  axis          = &hints->axis[dim];
      AF_Segment    segments      = axis->segments;
      AF_Segment    segment_limit = segments + axis->num_segments;
  #ifdef AF_SORT_SEGMENTS
      AF_Segment    segment_mid   = segments + axis->mid_segments;
  #endif
      FT_Pos        len_threshold, len_score;
      AF_Segment    seg1, seg2;
  
  
      len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
      if ( len_threshold == 0 )
        len_threshold = 1;
  
      len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 );
  
  #ifdef AF_SORT_SEGMENTS
      for ( seg1 = segments; seg1 < segment_mid; seg1++ )
      {
        if ( seg1->dir != axis->major_dir )
          continue;
  
        for ( seg2 = segment_mid; seg2 < segment_limit; seg2++ )
  #else
      /* now compare each segment to the others */
      for ( seg1 = segments; seg1 < segment_limit; seg1++ )
      {
        if ( seg1->dir != axis->major_dir )
          continue;
  
        for ( seg2 = segments; seg2 < segment_limit; seg2++ )
          if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos )
  #endif
          {
            FT_Pos  pos1 = seg1->pos;
            FT_Pos  pos2 = seg2->pos;
            FT_Pos  dist = pos2 - pos1;
  
  
            if ( dist < 0 )
              continue;
  
            {
              FT_Pos  min = seg1->min_coord;
              FT_Pos  max = seg1->max_coord;
              FT_Pos  len, score;
  
  
              if ( min < seg2->min_coord )
                min = seg2->min_coord;
  
              if ( max > seg2->max_coord )
                max = seg2->max_coord;
  
              len = max - min;
              if ( len >= len_threshold )
              {
                score = dist + len_score / len;
                if ( score < seg1->score )
                {
                  seg1->score = score;
                  seg1->link  = seg2;
                }
  
                if ( score < seg2->score )
                {
                  seg2->score = score;
                  seg2->link  = seg1;
                }
              }
            }
          }
      }
  #if 0
      }
  #endif
  
      /* now, compute the `serif' segments */
      for ( seg1 = segments; seg1 < segment_limit; seg1++ )
      {
        seg2 = seg1->link;
  
        if ( seg2 )
        {
          if ( seg2->link != seg1 )
          {
            seg1->link  = NULL;
            seg1->serif = seg2->link;
          }
        }
      }
    }
  
  
    FT_LOCAL_DEF( FT_Error )
    af_latin2_hints_compute_edges( AF_GlyphHints  hints,
                                   AF_Dimension   dim )
    {
      AF_AxisHints  axis   = &hints->axis[dim];
      FT_Error      error  = FT_Err_Ok;
      FT_Memory     memory = hints->memory;
      AF_LatinAxis  laxis  = &((AF_LatinMetrics)hints->metrics)->axis[dim];
  
      AF_Segment    segments      = axis->segments;
      AF_Segment    segment_limit = segments + axis->num_segments;
      AF_Segment    seg;
  
      AF_Direction  up_dir;
      FT_Fixed      scale;
      FT_Pos        edge_distance_threshold;
      FT_Pos        segment_length_threshold;
  
  
      axis->num_edges = 0;
  
      scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
                                           : hints->y_scale;
  
      up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP
                                            : AF_DIR_RIGHT;
  
      /*
       * We want to ignore very small (mostly serif) segments, we do that
       * by ignoring those that whose length is less than a given fraction
       * of the standard width. If there is no standard width, we ignore
       * those that are less than a given size in pixels
       *
       * also, unlink serif segments that are linked to segments farther
       * than 50% of the standard width
       */
      if ( dim == AF_DIMENSION_HORZ )
      {
        if ( laxis->width_count > 0 )
          segment_length_threshold = ( laxis->standard_width * 10 ) >> 4;
        else
          segment_length_threshold = FT_DivFix( 64, hints->y_scale );
      }
      else
        segment_length_threshold = 0;
  
      /**********************************************************************
       *
       * We will begin by generating a sorted table of edges for the
       * current direction.  To do so, we simply scan each segment and try
       * to find an edge in our table that corresponds to its position.
       *
       * If no edge is found, we create and insert a new edge in the
       * sorted table.  Otherwise, we simply add the segment to the edge's
       * list which will be processed in the second step to compute the
       * edge's properties.
       *
       * Note that the edges table is sorted along the segment/edge
       * position.
       *
       */
  
      edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
                                           scale );
      if ( edge_distance_threshold > 64 / 4 )
        edge_distance_threshold = 64 / 4;
  
      edge_distance_threshold = FT_DivFix( edge_distance_threshold,
                                           scale );
  
      for ( seg = segments; seg < segment_limit; seg++ )
      {
        AF_Edge  found = NULL;
        FT_Int   ee;
  
  
        if ( seg->height < segment_length_threshold )
          continue;
  
        /* A special case for serif edges: If they are smaller than */
        /* 1.5 pixels we ignore them.                               */
        if ( seg->serif )
        {
          FT_Pos  dist = seg->serif->pos - seg->pos;
  
  
          if ( dist < 0 )
            dist = -dist;
  
          if ( dist >= laxis->standard_width >> 1 )
          {
            /* unlink this serif, it is too distant from its reference stem */
            seg->serif = NULL;
          }
          else if ( 2*seg->height < 3 * segment_length_threshold )
            continue;
        }
  
        /* look for an edge corresponding to the segment */
        for ( ee = 0; ee < axis->num_edges; ee++ )
        {
          AF_Edge  edge = axis->edges + ee;
          FT_Pos   dist;
  
  
          dist = seg->pos - edge->fpos;
          if ( dist < 0 )
            dist = -dist;
  
          if ( dist < edge_distance_threshold && edge->dir == seg->dir )
          {
            found = edge;
            break;
          }
        }
  
        if ( !found )
        {
          AF_Edge   edge;
  
  
          /* insert a new edge in the list and */
          /* sort according to the position    */
          error = af_axis_hints_new_edge( axis, seg->pos, seg->dir, 0,
                                          memory, &edge );
          if ( error )
            goto Exit;
  
          /* add the segment to the new edge's list */
          FT_ZERO( edge );
  
          edge->first    = seg;
          edge->last     = seg;
          edge->dir      = seg->dir;
          edge->fpos     = seg->pos;
          edge->opos     = FT_MulFix( seg->pos, scale );
          edge->pos      = edge->opos;
          seg->edge_next = seg;
        }
        else
        {
          /* if an edge was found, simply add the segment to the edge's */
          /* list                                                       */
          seg->edge_next         = found->first;
          found->last->edge_next = seg;
          found->last            = seg;
        }
      }
  
  
      /**********************************************************************
       *
       * Good, we will now compute each edge's properties according to
       * segments found on its position.  Basically, these are:
       *
       * - edge's main direction
       * - stem edge, serif edge or both (which defaults to stem then)
       * - rounded edge, straight or both (which defaults to straight)
       * - link for edge
       *
       */
  
      /* first of all, set the `edge' field in each segment -- this is */
      /* required in order to compute edge links                       */
  
      /*
       * Note that removing this loop and setting the `edge' field of each
       * segment directly in the code above slows down execution speed for
       * some reasons on platforms like the Sun.
       */
      {
        AF_Edge  edges      = axis->edges;
        AF_Edge  edge_limit = edges + axis->num_edges;
        AF_Edge  edge;
  
  
        for ( edge = edges; edge < edge_limit; edge++ )
        {
          seg = edge->first;
          if ( seg )
            do
            {
              seg->edge = edge;
              seg       = seg->edge_next;
  
            } while ( seg != edge->first );
        }
  
        /* now, compute each edge properties */
        for ( edge = edges; edge < edge_limit; edge++ )
        {
          FT_Int  is_round    = 0;  /* does it contain round segments?    */
          FT_Int  is_straight = 0;  /* does it contain straight segments? */
  #if 0
          FT_Pos  ups         = 0;  /* number of upwards segments         */
          FT_Pos  downs       = 0;  /* number of downwards segments       */
  #endif
  
  
          seg = edge->first;
  
          do
          {
            FT_Bool  is_serif;
  
  
            /* check for roundness of segment */
            if ( seg->flags & AF_EDGE_ROUND )
              is_round++;
            else
              is_straight++;
  
  #if 0
            /* check for segment direction */
            if ( seg->dir == up_dir )
              ups   += seg->max_coord-seg->min_coord;
            else
              downs += seg->max_coord-seg->min_coord;
  #endif
  
            /* check for links -- if seg->serif is set, then seg->link must */
            /* be ignored                                                   */
            is_serif = (FT_Bool)( seg->serif               &&
                                  seg->serif->edge         &&
                                  seg->serif->edge != edge );
  
            if ( ( seg->link && seg->link->edge ) || is_serif )
            {
              AF_Edge     edge2;
              AF_Segment  seg2;
  
  
              edge2 = edge->link;
              seg2  = seg->link;
  
              if ( is_serif )
              {
                seg2  = seg->serif;
                edge2 = edge->serif;
              }
  
              if ( edge2 )
              {
                FT_Pos  edge_delta;
                FT_Pos  seg_delta;
  
  
                edge_delta = edge->fpos - edge2->fpos;
                if ( edge_delta < 0 )
                  edge_delta = -edge_delta;
  
                seg_delta = seg->pos - seg2->pos;
                if ( seg_delta < 0 )
                  seg_delta = -seg_delta;
  
                if ( seg_delta < edge_delta )
                  edge2 = seg2->edge;
              }
              else
                edge2 = seg2->edge;
  
              if ( is_serif )
              {
                edge->serif   = edge2;
                edge2->flags |= AF_EDGE_SERIF;
              }
              else
                edge->link  = edge2;
            }
  
            seg = seg->edge_next;
  
          } while ( seg != edge->first );
  
          /* set the round/straight flags */
          edge->flags = AF_EDGE_NORMAL;
  
          if ( is_round > 0 && is_round >= is_straight )
            edge->flags |= AF_EDGE_ROUND;
  
  #if 0
          /* set the edge's main direction */
          edge->dir = AF_DIR_NONE;
  
          if ( ups > downs )
            edge->dir = (FT_Char)up_dir;
  
          else if ( ups < downs )
            edge->dir = (FT_Char)-up_dir;
  
          else if ( ups == downs )
            edge->dir = 0;  /* both up and down! */
  #endif
  
          /* gets rid of serifs if link is set                */
          /* XXX: This gets rid of many unpleasant artefacts! */
          /*      Example: the `c' in cour.pfa at size 13     */
  
          if ( edge->serif && edge->link )
            edge->serif = NULL;
        }
      }
  
    Exit:
      return error;
    }
  
  
    FT_LOCAL_DEF( FT_Error )
    af_latin2_hints_detect_features( AF_GlyphHints  hints,
                                     AF_Dimension   dim )
    {
      FT_Error  error;
  
  
      error = af_latin2_hints_compute_segments( hints, dim );
      if ( !error )
      {
        af_latin2_hints_link_segments( hints, dim );
  
        error = af_latin2_hints_compute_edges( hints, dim );
      }
      return error;
    }
  
  
    static void
    af_latin2_hints_compute_blue_edges( AF_GlyphHints    hints,
                                        AF_LatinMetrics  metrics )
    {
      AF_AxisHints  axis       = &hints->axis[AF_DIMENSION_VERT];
      AF_Edge       edge       = axis->edges;
      AF_Edge       edge_limit = edge + axis->num_edges;
      AF_LatinAxis  latin      = &metrics->axis[AF_DIMENSION_VERT];
      FT_Fixed      scale      = latin->scale;
      FT_Pos        best_dist0;  /* initial threshold */
  
  
      /* compute the initial threshold as a fraction of the EM size */
      best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale );
  
      if ( best_dist0 > 64 / 2 )
        best_dist0 = 64 / 2;
  
      /* compute which blue zones are active, i.e. have their scaled */
      /* size < 3/4 pixels                                           */
  
      /* for each horizontal edge search the blue zone which is closest */
      for ( ; edge < edge_limit; edge++ )
      {
        FT_Int    bb;
        AF_Width  best_blue = NULL;
        FT_Pos    best_dist = best_dist0;
  
        for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
        {
          AF_LatinBlue  blue = latin->blues + bb;
          FT_Bool       is_top_blue, is_major_dir;
  
  
          /* skip inactive blue zones (i.e., those that are too small) */
          if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) )
            continue;
  
          /* if it is a top zone, check for right edges -- if it is a bottom */
          /* zone, check for left edges                                      */
          /*                                                                 */
          /* of course, that's for TrueType                                  */
          is_top_blue  = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 );
          is_major_dir = FT_BOOL( edge->dir == axis->major_dir );
  
          /* if it is a top zone, the edge must be against the major    */
          /* direction; if it is a bottom zone, it must be in the major */
          /* direction                                                  */
          if ( is_top_blue ^ is_major_dir )
          {
            FT_Pos     dist;
            AF_Width   compare;
  
  
            /* if it's a rounded edge, compare it to the overshoot position */
            /* if it's a flat edge, compare it to the reference position    */
            if ( edge->flags & AF_EDGE_ROUND )
              compare = &blue->shoot;
            else
              compare = &blue->ref;
  
            dist = edge->fpos - compare->org;
            if ( dist < 0 )
              dist = -dist;
  
            dist = FT_MulFix( dist, scale );
            if ( dist < best_dist )
            {
              best_dist = dist;
              best_blue = compare;
            }
  
  #if 0
            /* now, compare it to the overshoot position if the edge is     */
            /* rounded, and if the edge is over the reference position of a */
            /* top zone, or under the reference position of a bottom zone   */
            if ( edge->flags & AF_EDGE_ROUND && dist != 0 )
            {
              FT_Bool  is_under_ref = FT_BOOL( edge->fpos < blue->ref.org );
  
  
              if ( is_top_blue ^ is_under_ref )
              {
                blue = latin->blues + bb;
                dist = edge->fpos - blue->shoot.org;
                if ( dist < 0 )
                  dist = -dist;
  
                dist = FT_MulFix( dist, scale );
                if ( dist < best_dist )
                {
                  best_dist = dist;
                  best_blue = & blue->shoot;
                }
              }
            }
  #endif
          }
        }
  
        if ( best_blue )
          edge->blue_edge = best_blue;
      }
    }
  
  
    static FT_Error
    af_latin2_hints_init( AF_GlyphHints    hints,
                          AF_LatinMetrics  metrics )
    {
      FT_Render_Mode  mode;
      FT_UInt32       scaler_flags, other_flags;
      FT_Face         face = metrics->root.scaler.face;
  
  
      af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics );
  
      /*
       * correct x_scale and y_scale if needed, since they may have
       * been modified `af_latin2_metrics_scale_dim' above
       */
      hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale;
      hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta;
      hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale;
      hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta;
  
      /* compute flags depending on render mode, etc. */
      mode = metrics->root.scaler.render_mode;
  
  #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */
      if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V )
        metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL;
  #endif
  
      scaler_flags = hints->scaler_flags;
      other_flags  = 0;
  
      /*
       * We snap the width of vertical stems for the monochrome and
       * horizontal LCD rendering targets only.
       */
      if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD )
        other_flags |= AF_LATIN_HINTS_HORZ_SNAP;
  
      /*
       * We snap the width of horizontal stems for the monochrome and
       * vertical LCD rendering targets only.
       */
      if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V )
        other_flags |= AF_LATIN_HINTS_VERT_SNAP;
  
      /*
       * We adjust stems to full pixels unless in `light' or `lcd' mode.
       */
      if ( mode != FT_RENDER_MODE_LIGHT && mode != FT_RENDER_MODE_LCD )
        other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
  
      if ( mode == FT_RENDER_MODE_MONO )
        other_flags |= AF_LATIN_HINTS_MONO;
  
      /*
       * In `light' or `lcd' mode we disable horizontal hinting completely.
       * We also do it if the face is italic.
       */
      if ( mode == FT_RENDER_MODE_LIGHT || mode == FT_RENDER_MODE_LCD ||
           ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0          )
        scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL;
  
  #ifdef AF_CONFIG_OPTION_USE_WARPER
      /* get (global) warper flag */
      if ( !metrics->root.globals->module->warping )
        scaler_flags |= AF_SCALER_FLAG_NO_WARPER;
  #endif
  
      hints->scaler_flags = scaler_flags;
      hints->other_flags  = other_flags;
  
      return 0;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****        L A T I N   G L Y P H   G R I D - F I T T I N G        *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    /* snap a given width in scaled coordinates to one of the */
    /* current standard widths                                */
  
    static FT_Pos
    af_latin2_snap_width( AF_Width  widths,
                          FT_UInt   count,
                          FT_Pos    width )
    {
      FT_UInt  n;
      FT_Pos   best      = 64 + 32 + 2;
      FT_Pos   reference = width;
      FT_Pos   scaled;
  
  
      for ( n = 0; n < count; n++ )
      {
        FT_Pos  w;
        FT_Pos  dist;
  
  
        w = widths[n].cur;
        dist = width - w;
        if ( dist < 0 )
          dist = -dist;
        if ( dist < best )
        {
          best      = dist;
          reference = w;
        }
      }
  
      scaled = FT_PIX_ROUND( reference );
  
      if ( width >= reference )
      {
        if ( width < scaled + 48 )
          width = reference;
      }
      else
      {
        if ( width > scaled - 48 )
          width = reference;
      }
  
      return width;
    }
  
  
    /* compute the snapped width of a given stem */
  
    static FT_Pos
    af_latin2_compute_stem_width( AF_GlyphHints  hints,
                                  AF_Dimension   dim,
                                  FT_Pos         width,
                                  FT_UInt        base_flags,
                                  FT_UInt        stem_flags )
    {
      AF_LatinMetrics  metrics  = (AF_LatinMetrics) hints->metrics;
      AF_LatinAxis     axis     = & metrics->axis[dim];
      FT_Pos           dist     = width;
      FT_Int           sign     = 0;
      FT_Int           vertical = ( dim == AF_DIMENSION_VERT );
  
      FT_UNUSED( base_flags );
  
  
      if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ||
            axis->extra_light                      )
        return width;
  
      if ( dist < 0 )
      {
        dist = -width;
        sign = 1;
      }
  
      if ( (  vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ||
           ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) )
      {
        /* smooth hinting process: very lightly quantize the stem width */
  
        /* leave the widths of serifs alone */
  
        if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) )
          goto Done_Width;
  
  #if 0
        else if ( ( base_flags & AF_EDGE_ROUND ) )
        {
          if ( dist < 80 )
            dist = 64;
        }
        else if ( dist < 56 )
          dist = 56;
  #endif
        if ( axis->width_count > 0 )
        {
          FT_Pos  delta;
  
  
          /* compare to standard width */
          if ( axis->width_count > 0 )
          {
            delta = dist - axis->widths[0].cur;
  
            if ( delta < 0 )
              delta = -delta;
  
            if ( delta < 40 )
            {
              dist = axis->widths[0].cur;
              if ( dist < 48 )
                dist = 48;
  
              goto Done_Width;
            }
          }
  
          if ( dist < 3 * 64 )
          {
            delta  = dist & 63;
            dist  &= -64;
  
            if ( delta < 10 )
              dist += delta;
  
            else if ( delta < 32 )
              dist += 10;
  
            else if ( delta < 54 )
              dist += 54;
  
            else
              dist += delta;
          }
          else
            dist = ( dist + 32 ) & ~63;
        }
      }
      else
      {
        /* strong hinting process: snap the stem width to integer pixels */
        FT_Pos  org_dist = dist;
  
  
        dist = af_latin2_snap_width( axis->widths, axis->width_count, dist );
  
        if ( vertical )
        {
          /* in the case of vertical hinting, always round */
          /* the stem heights to integer pixels            */
  
          if ( dist >= 64 )
            dist = ( dist + 16 ) & ~63;
          else
            dist = 64;
        }
        else
        {
          if ( AF_LATIN_HINTS_DO_MONO( hints ) )
          {
            /* monochrome horizontal hinting: snap widths to integer pixels */
            /* with a different threshold                                   */
  
            if ( dist < 64 )
              dist = 64;
            else
              dist = ( dist + 32 ) & ~63;
          }
          else
          {
            /* for horizontal anti-aliased hinting, we adopt a more subtle */
            /* approach: we strengthen small stems, round stems whose size */
            /* is between 1 and 2 pixels to an integer, otherwise nothing  */
  
            if ( dist < 48 )
              dist = ( dist + 64 ) >> 1;
  
            else if ( dist < 128 )
            {
              /* We only round to an integer width if the corresponding */
              /* distortion is less than 1/4 pixel.  Otherwise this     */
              /* makes everything worse since the diagonals, which are  */
              /* not hinted, appear a lot bolder or thinner than the    */
              /* vertical stems.                                        */
  
              FT_Int  delta;
  
  
              dist = ( dist + 22 ) & ~63;
              delta = dist - org_dist;
              if ( delta < 0 )
                delta = -delta;
  
              if ( delta >= 16 )
              {
                dist = org_dist;
                if ( dist < 48 )
                  dist = ( dist + 64 ) >> 1;
              }
            }
            else
              /* round otherwise to prevent color fringes in LCD mode */
              dist = ( dist + 32 ) & ~63;
          }
        }
      }
  
    Done_Width:
      if ( sign )
        dist = -dist;
  
      return dist;
    }
  
  
    /* align one stem edge relative to the previous stem edge */
  
    static void
    af_latin2_align_linked_edge( AF_GlyphHints  hints,
                                 AF_Dimension   dim,
                                 AF_Edge        base_edge,
                                 AF_Edge        stem_edge )
    {
      FT_Pos  dist = stem_edge->opos - base_edge->opos;
  
      FT_Pos  fitted_width = af_latin2_compute_stem_width( hints, dim, dist,
                                                           base_edge->flags,
                                                           stem_edge->flags );
  
  
      stem_edge->pos = base_edge->pos + fitted_width;
  
      FT_TRACE5(( "LINK: edge %d (opos=%.2f) linked to (%.2f), "
                  "dist was %.2f, now %.2f\n",
                  stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0,
                  stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 ));
    }
  
  
    static void
    af_latin2_align_serif_edge( AF_GlyphHints  hints,
                                AF_Edge        base,
                                AF_Edge        serif )
    {
      FT_UNUSED( hints );
  
      serif->pos = base->pos + ( serif->opos - base->opos );
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*************************************************************************/
    /****                                                                 ****/
    /****                    E D G E   H I N T I N G                      ****/
    /****                                                                 ****/
    /*************************************************************************/
    /*************************************************************************/
    /*************************************************************************/
  
  
    static void
    af_latin2_hint_edges( AF_GlyphHints  hints,
                          AF_Dimension   dim )
    {
      AF_AxisHints  axis       = &hints->axis[dim];
      AF_Edge       edges      = axis->edges;
      AF_Edge       edge_limit = edges + axis->num_edges;
      AF_Edge       edge;
      AF_Edge       anchor     = NULL;
      FT_Int        has_serifs = 0;
      FT_Pos        anchor_drift = 0;
  
  
  
      FT_TRACE5(( "==== hinting %s edges =====\n",
                  dim == AF_DIMENSION_HORZ ? "vertical" : "horizontal" ));
  
      /* we begin by aligning all stems relative to the blue zone */
      /* if needed -- that's only for horizontal edges            */
  
      if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) )
      {
        for ( edge = edges; edge < edge_limit; edge++ )
        {
          AF_Width  blue;
          AF_Edge   edge1, edge2;
  
  
          if ( edge->flags & AF_EDGE_DONE )
            continue;
  
          blue  = edge->blue_edge;
          edge1 = NULL;
          edge2 = edge->link;
  
          if ( blue )
          {
            edge1 = edge;
          }
          else if ( edge2 && edge2->blue_edge )
          {
            blue  = edge2->blue_edge;
            edge1 = edge2;
            edge2 = edge;
          }
  
          if ( !edge1 )
            continue;
  
          FT_TRACE5(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), "
                      "was (%.2f)\n",
                      edge1-edges, edge1->opos / 64.0, blue->fit / 64.0,
                      edge1->pos / 64.0 ));
  
          edge1->pos    = blue->fit;
          edge1->flags |= AF_EDGE_DONE;
  
          if ( edge2 && !edge2->blue_edge )
          {
            af_latin2_align_linked_edge( hints, dim, edge1, edge2 );
            edge2->flags |= AF_EDGE_DONE;
          }
  
          if ( !anchor )
          {
            anchor = edge;
  
            anchor_drift = ( anchor->pos - anchor->opos );
            if ( edge2 )
              anchor_drift = ( anchor_drift +
                               ( edge2->pos - edge2->opos ) ) >> 1;
          }
        }
      }
  
      /* now we will align all stem edges, trying to maintain the */
      /* relative order of stems in the glyph                     */
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        AF_Edge  edge2;
  
  
        if ( edge->flags & AF_EDGE_DONE )
          continue;
  
        /* skip all non-stem edges */
        edge2 = edge->link;
        if ( !edge2 )
        {
          has_serifs++;
          continue;
        }
  
        /* now align the stem */
  
        /* this should not happen, but it's better to be safe */
        if ( edge2->blue_edge )
        {
          FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges ));
  
          af_latin2_align_linked_edge( hints, dim, edge2, edge );
          edge->flags |= AF_EDGE_DONE;
          continue;
        }
  
        if ( !anchor )
        {
          FT_Pos  org_len, org_center, cur_len;
          FT_Pos  cur_pos1, error1, error2, u_off, d_off;
  
  
          org_len = edge2->opos - edge->opos;
          cur_len = af_latin2_compute_stem_width( hints, dim, org_len,
                                                  edge->flags,
                                                  edge2->flags );
          if ( cur_len <= 64 )
            u_off = d_off = 32;
          else
          {
            u_off = 38;
            d_off = 26;
          }
  
          if ( cur_len < 96 )
          {
            org_center = edge->opos + ( org_len >> 1 );
  
            cur_pos1   = FT_PIX_ROUND( org_center );
  
            error1 = org_center - ( cur_pos1 - u_off );
            if ( error1 < 0 )
              error1 = -error1;
  
            error2 = org_center - ( cur_pos1 + d_off );
            if ( error2 < 0 )
              error2 = -error2;
  
            if ( error1 < error2 )
              cur_pos1 -= u_off;
            else
              cur_pos1 += d_off;
  
            edge->pos  = cur_pos1 - cur_len / 2;
            edge2->pos = edge->pos + cur_len;
          }
          else
            edge->pos = FT_PIX_ROUND( edge->opos );
  
          FT_TRACE5(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)"
                      " snapped to (%.2f) (%.2f)\n",
                      edge-edges, edge->opos / 64.0,
                      edge2-edges, edge2->opos / 64.0,
                      edge->pos / 64.0, edge2->pos / 64.0 ));
          anchor = edge;
  
          edge->flags |= AF_EDGE_DONE;
  
          af_latin2_align_linked_edge( hints, dim, edge, edge2 );
  
          edge2->flags |= AF_EDGE_DONE;
  
          anchor_drift = ( ( anchor->pos - anchor->opos ) +
                           ( edge2->pos - edge2->opos ) ) >> 1;
  
          FT_TRACE5(( "DRIFT: %.2f\n", anchor_drift/64.0 ));
        }
        else
        {
          FT_Pos   org_pos, org_len, org_center, cur_center, cur_len;
          FT_Pos   org_left, org_right;
  
  
          org_pos    = edge->opos + anchor_drift;
          org_len    = edge2->opos - edge->opos;
          org_center = org_pos + ( org_len >> 1 );
  
          cur_len = af_latin2_compute_stem_width( hints, dim, org_len,
                                                  edge->flags,
                                                  edge2->flags );
  
          org_left  = org_pos + ( ( org_len - cur_len ) >> 1 );
          org_right = org_pos + ( ( org_len + cur_len ) >> 1 );
  
          FT_TRACE5(( "ALIGN: left=%.2f right=%.2f ",
                      org_left / 64.0, org_right / 64.0 ));
          cur_center = org_center;
  
          if ( edge2->flags & AF_EDGE_DONE )
          {
            FT_TRACE5(( "\n" ));
            edge->pos = edge2->pos - cur_len;
          }
          else
          {
           /* we want to compare several displacement, and choose
            * the one that increases fitness while minimizing
            * distortion as well
            */
            FT_Pos   displacements[6], scores[6], org, fit, delta;
            FT_UInt  count = 0;
  
            /* note: don't even try to fit tiny stems */
            if ( cur_len < 32 )
            {
              FT_TRACE5(( "tiny stem\n" ));
              goto AlignStem;
            }
  
            /* if the span is within a single pixel, don't touch it */
            if ( FT_PIX_FLOOR( org_left ) == FT_PIX_CEIL( org_right ) )
            {
              FT_TRACE5(( "single pixel stem\n" ));
              goto AlignStem;
            }
  
            if ( cur_len <= 96 )
            {
             /* we want to avoid the absolute worst case which is
              * when the left and right edges of the span each represent
              * about 50% of the gray. we'd better want to change this
              * to 25/75%, since this is much more pleasant to the eye with
              * very acceptable distortion
              */
              FT_Pos  frac_left  = org_left  & 63;
              FT_Pos  frac_right = org_right & 63;
  
              if ( frac_left  >= 22 && frac_left  <= 42 &&
                   frac_right >= 22 && frac_right <= 42 )
              {
                org = frac_left;
                fit = ( org <= 32 ) ? 16 : 48;
                delta = FT_ABS( fit - org );
                displacements[count] = fit - org;
                scores[count++]      = delta;
                FT_TRACE5(( "dispA=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
  
                org = frac_right;
                fit = ( org <= 32 ) ? 16 : 48;
                delta = FT_ABS( fit - org );
                displacements[count] = fit - org;
                scores[count++]     = delta;
                FT_TRACE5(( "dispB=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
              }
            }
  
            /* snapping the left edge to the grid */
            org   = org_left;
            fit   = FT_PIX_ROUND( org );
            delta = FT_ABS( fit - org );
            displacements[count] = fit - org;
            scores[count++]      = delta;
            FT_TRACE5(( "dispC=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
  
            /* snapping the right edge to the grid */
            org   = org_right;
            fit   = FT_PIX_ROUND( org );
            delta = FT_ABS( fit - org );
            displacements[count] = fit - org;
            scores[count++]      = delta;
            FT_TRACE5(( "dispD=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
  
            /* now find the best displacement */
            {
              FT_Pos  best_score = scores[0];
              FT_Pos  best_disp  = displacements[0];
              FT_UInt nn;
  
              for ( nn = 1; nn < count; nn++ )
              {
                if ( scores[nn] < best_score )
                {
                  best_score = scores[nn];
                  best_disp  = displacements[nn];
                }
              }
  
              cur_center = org_center + best_disp;
            }
            FT_TRACE5(( "\n" ));
          }
  
        AlignStem:
          edge->pos  = cur_center - ( cur_len >> 1 );
          edge2->pos = edge->pos + cur_len;
  
          FT_TRACE5(( "STEM1: %d (opos=%.2f) to %d (opos=%.2f)"
                      " snapped to (%.2f) and (%.2f),"
                      " org_len=%.2f cur_len=%.2f\n",
                      edge-edges, edge->opos / 64.0,
                      edge2-edges, edge2->opos / 64.0,
                      edge->pos / 64.0, edge2->pos / 64.0,
                      org_len / 64.0, cur_len / 64.0 ));
  
          edge->flags  |= AF_EDGE_DONE;
          edge2->flags |= AF_EDGE_DONE;
  
          if ( edge > edges && edge->pos < edge[-1].pos )
          {
            FT_TRACE5(( "BOUND: %d (pos=%.2f) to (%.2f)\n",
                        edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
            edge->pos = edge[-1].pos;
          }
        }
      }
  
      /* make sure that lowercase m's maintain their symmetry */
  
      /* In general, lowercase m's have six vertical edges if they are sans */
      /* serif, or twelve if they are with serifs.  This implementation is  */
      /* based on that assumption, and seems to work very well with most    */
      /* faces.  However, if for a certain face this assumption is not      */
      /* true, the m is just rendered like before.  In addition, any stem   */
      /* correction will only be applied to symmetrical glyphs (even if the */
      /* glyph is not an m), so the potential for unwanted distortion is    */
      /* relatively low.                                                    */
  
      /* We don't handle horizontal edges since we can't easily assure that */
      /* the third (lowest) stem aligns with the base line; it might end up */
      /* one pixel higher or lower.                                         */
  
  #if 0
      {
        FT_Int  n_edges = edge_limit - edges;
  
  
        if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) )
        {
          AF_Edge  edge1, edge2, edge3;
          FT_Pos   dist1, dist2, span, delta;
  
  
          if ( n_edges == 6 )
          {
            edge1 = edges;
            edge2 = edges + 2;
            edge3 = edges + 4;
          }
          else
          {
            edge1 = edges + 1;
            edge2 = edges + 5;
            edge3 = edges + 9;
          }
  
          dist1 = edge2->opos - edge1->opos;
          dist2 = edge3->opos - edge2->opos;
  
          span = dist1 - dist2;
          if ( span < 0 )
            span = -span;
  
          if ( span < 8 )
          {
            delta = edge3->pos - ( 2 * edge2->pos - edge1->pos );
            edge3->pos -= delta;
            if ( edge3->link )
              edge3->link->pos -= delta;
  
            /* move the serifs along with the stem */
            if ( n_edges == 12 )
            {
              ( edges + 8 )->pos -= delta;
              ( edges + 11 )->pos -= delta;
            }
  
            edge3->flags |= AF_EDGE_DONE;
            if ( edge3->link )
              edge3->link->flags |= AF_EDGE_DONE;
          }
        }
      }
  #endif
  
      if ( has_serifs || !anchor )
      {
        /*
         * now hint the remaining edges (serifs and single) in order
         * to complete our processing
         */
        for ( edge = edges; edge < edge_limit; edge++ )
        {
          FT_Pos  delta;
  
  
          if ( edge->flags & AF_EDGE_DONE )
            continue;
  
          delta = 1000;
  
          if ( edge->serif )
          {
            delta = edge->serif->opos - edge->opos;
            if ( delta < 0 )
              delta = -delta;
          }
  
          if ( delta < 64 + 16 )
          {
            af_latin2_align_serif_edge( hints, edge->serif, edge );
            FT_TRACE5(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)"
                        " aligned to (%.2f)\n",
                        edge-edges, edge->opos / 64.0,
                        edge->serif - edges, edge->serif->opos / 64.0,
                        edge->pos / 64.0 ));
          }
          else if ( !anchor )
          {
            FT_TRACE5(( "SERIF_ANCHOR: edge %d (opos=%.2f)"
                        " snapped to (%.2f)\n",
                        edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
            edge->pos = FT_PIX_ROUND( edge->opos );
            anchor    = edge;
          }
          else
          {
            AF_Edge  before, after;
  
  
            for ( before = edge - 1; before >= edges; before-- )
              if ( before->flags & AF_EDGE_DONE )
                break;
  
            for ( after = edge + 1; after < edge_limit; after++ )
              if ( after->flags & AF_EDGE_DONE )
                break;
  
            if ( before >= edges && before < edge   &&
                 after < edge_limit && after > edge )
            {
              if ( after->opos == before->opos )
                edge->pos = before->pos;
              else
                edge->pos = before->pos +
                            FT_MulDiv( edge->opos - before->opos,
                                       after->pos - before->pos,
                                       after->opos - before->opos );
              FT_TRACE5(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)"
                          " from %d (opos=%.2f)\n",
                          edge-edges, edge->opos / 64.0, edge->pos / 64.0,
                          before - edges, before->opos / 64.0 ));
            }
            else
            {
              edge->pos = anchor->pos +
                          ( ( edge->opos - anchor->opos + 16 ) & ~31 );
  
              FT_TRACE5(( "SERIF_LINK2: edge %d (opos=%.2f)"
                          " snapped to (%.2f)\n",
                          edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
            }
          }
  
          edge->flags |= AF_EDGE_DONE;
  
          if ( edge > edges && edge->pos < edge[-1].pos )
            edge->pos = edge[-1].pos;
  
          if ( edge + 1 < edge_limit        &&
               edge[1].flags & AF_EDGE_DONE &&
               edge->pos > edge[1].pos      )
            edge->pos = edge[1].pos;
        }
      }
    }
  
  
    static FT_Error
    af_latin2_hints_apply( FT_UInt          glyph_index,
                           AF_GlyphHints    hints,
                           FT_Outline*      outline,
                           AF_LatinMetrics  metrics )
    {
      FT_Error  error;
      int       dim;
  
      FT_UNUSED( glyph_index );
  
  
      error = af_glyph_hints_reload( hints, outline );
      if ( error )
        goto Exit;
  
      /* analyze glyph outline */
      if ( AF_HINTS_DO_HORIZONTAL( hints ) )
      {
        error = af_latin2_hints_detect_features( hints, AF_DIMENSION_HORZ );
        if ( error )
          goto Exit;
      }
  
      if ( AF_HINTS_DO_VERTICAL( hints ) )
      {
        error = af_latin2_hints_detect_features( hints, AF_DIMENSION_VERT );
        if ( error )
          goto Exit;
  
        af_latin2_hints_compute_blue_edges( hints, metrics );
      }
  
      /* grid-fit the outline */
      for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
      {
  #ifdef AF_CONFIG_OPTION_USE_WARPER
        if ( dim == AF_DIMENSION_HORZ                                  &&
             metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL &&
             AF_HINTS_DO_WARP( hints )                                 )
        {
          AF_WarperRec  warper;
          FT_Fixed      scale;
          FT_Pos        delta;
  
  
          af_warper_compute( &warper, hints, dim, &scale, &delta );
          af_glyph_hints_scale_dim( hints, dim, scale, delta );
          continue;
        }
  #endif /* AF_CONFIG_OPTION_USE_WARPER */
  
        if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
             ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) )   )
        {
          af_latin2_hint_edges( hints, (AF_Dimension)dim );
          af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim );
          af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
          af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim );
        }
      }
      af_glyph_hints_save( hints, outline );
  
    Exit:
      return error;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****              L A T I N   S C R I P T   C L A S S              *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  
    AF_DEFINE_WRITING_SYSTEM_CLASS(
      af_latin2_writing_system_class,
  
      AF_WRITING_SYSTEM_LATIN2,
  
      sizeof ( AF_LatinMetricsRec ),
  
      (AF_WritingSystem_InitMetricsFunc) af_latin2_metrics_init,        /* style_metrics_init    */
      (AF_WritingSystem_ScaleMetricsFunc)af_latin2_metrics_scale,       /* style_metrics_scale   */
      (AF_WritingSystem_DoneMetricsFunc) NULL,                          /* style_metrics_done    */
      (AF_WritingSystem_GetStdWidthsFunc)af_latin2_get_standard_widths, /* style_metrics_getstdw */
  
      (AF_WritingSystem_InitHintsFunc)   af_latin2_hints_init,          /* style_hints_init      */
      (AF_WritingSystem_ApplyHintsFunc)  af_latin2_hints_apply          /* style_hints_apply     */
    )
  
  #else /* !FT_OPTION_AUTOFIT2 */
  
    /* ANSI C doesn't like empty source files */
    typedef int  _af_latin2_dummy;
  
  #endif /* !FT_OPTION_AUTOFIT2 */
  
  
  /* END */
  

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