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

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• Hash : c7f26a19
  Author :
  Date : 2011-03-19T02:28:21
  

  C++ compilation fixes. * src/autofit/aflatin.c (af_latin_hints_apply), src/autofit/afcjk.c (af_cjk_hints_apply): Use cast for `dim'.

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• src/autofit/afcjk.c

• /***************************************************************************/
  /*                                                                         */
  /*  afcjk.c                                                                */
  /*                                                                         */
  /*    Auto-fitter hinting routines for CJK script (body).                  */
  /*                                                                         */
  /*  Copyright 2006-2011 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.                                        */
  /*                                                                         */
  /***************************************************************************/
  
    /*
     *  The algorithm is based on akito's autohint patch, available here:
     *
     *  http://www.kde.gr.jp/~akito/patch/freetype2/
     *
     */
  
  #include "aftypes.h"
  #include "aflatin.h"
  
  
  #ifdef AF_CONFIG_OPTION_CJK
  
  #include "afcjk.h"
  #include "aferrors.h"
  
  
  #ifdef AF_CONFIG_OPTION_USE_WARPER
  #include "afwarp.h"
  #endif
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****              C J K   G L O B A L   M E T R I C S              *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    FT_LOCAL_DEF( FT_Error )
    af_cjk_metrics_init( AF_LatinMetrics  metrics,
                         FT_Face          face )
    {
      FT_CharMap  oldmap = face->charmap;
  
  
      metrics->units_per_em = face->units_per_EM;
  
      /* TODO are there blues? */
  
      if ( FT_Select_Charmap( face, FT_ENCODING_UNICODE ) )
        face->charmap = NULL;
      else
      {
        /* latin's version would suffice */
        af_latin_metrics_init_widths( metrics, face, 0x7530 );
        af_latin_metrics_check_digits( metrics, face );
      }
  
      FT_Set_Charmap( face, oldmap );
  
      return AF_Err_Ok;
    }
  
  
    static void
    af_cjk_metrics_scale_dim( AF_LatinMetrics  metrics,
                              AF_Scaler        scaler,
                              AF_Dimension     dim )
    {
      AF_LatinAxis  axis;
  
  
      axis = &metrics->axis[dim];
  
      if ( dim == AF_DIMENSION_HORZ )
      {
        axis->scale = scaler->x_scale;
        axis->delta = scaler->x_delta;
      }
      else
      {
        axis->scale = scaler->y_scale;
        axis->delta = scaler->y_delta;
      }
    }
  
  
    FT_LOCAL_DEF( void )
    af_cjk_metrics_scale( AF_LatinMetrics  metrics,
                          AF_Scaler        scaler )
    {
      metrics->root.scaler = *scaler;
  
      af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
      af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****              C J K   G L Y P H   A N A L Y S I S              *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    static FT_Error
    af_cjk_hints_compute_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;
      FT_Error      error;
      AF_Segment    seg;
  
  
      error = af_latin_hints_compute_segments( hints, dim );
      if ( error )
        return error;
  
      /* a segment is round if it doesn't have successive */
      /* on-curve points.                                 */
      for ( seg = segments; seg < segment_limit; seg++ )
      {
        AF_Point  pt   = seg->first;
        AF_Point  last = seg->last;
        AF_Flags  f0   = (AF_Flags)(pt->flags & AF_FLAG_CONTROL);
        AF_Flags  f1;
  
  
        seg->flags &= ~AF_EDGE_ROUND;
  
        for ( ; pt != last; f0 = f1 )
        {
          pt = pt->next;
          f1 = (AF_Flags)(pt->flags & AF_FLAG_CONTROL);
  
          if ( !f0 && !f1 )
            break;
  
          if ( pt == last )
            seg->flags |= AF_EDGE_ROUND;
        }
      }
  
      return AF_Err_Ok;
    }
  
  
    static void
    af_cjk_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;
      AF_Direction  major_dir     = axis->major_dir;
      AF_Segment    seg1, seg2;
      FT_Pos        len_threshold;
      FT_Pos        dist_threshold;
  
  
      len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
  
      dist_threshold = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
                                                    : hints->y_scale;
      dist_threshold = FT_DivFix( 64 * 3, dist_threshold );
  
      /* now compare each segment to the others */
      for ( seg1 = segments; seg1 < segment_limit; seg1++ )
      {
        /* the fake segments are for metrics hinting only */
        if ( seg1->first == seg1->last )
          continue;
  
        if ( seg1->dir != major_dir )
          continue;
  
        for ( seg2 = segments; seg2 < segment_limit; seg2++ )
          if ( seg2 != seg1 && seg1->dir + seg2->dir == 0 )
          {
            FT_Pos  dist = seg2->pos - seg1->pos;
  
  
            if ( dist < 0 )
              continue;
  
            {
              FT_Pos  min = seg1->min_coord;
              FT_Pos  max = seg1->max_coord;
              FT_Pos  len;
  
  
              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 )
              {
                if ( dist * 8 < seg1->score * 9                        &&
                     ( dist * 8 < seg1->score * 7 || seg1->len < len ) )
                {
                  seg1->score = dist;
                  seg1->len   = len;
                  seg1->link  = seg2;
                }
  
                if ( dist * 8 < seg2->score * 9                        &&
                     ( dist * 8 < seg2->score * 7 || seg2->len < len ) )
                {
                  seg2->score = dist;
                  seg2->len   = len;
                  seg2->link  = seg1;
                }
              }
            }
          }
      }
  
      /*
       *  now compute the `serif' segments
       *
       *  In Hanzi, some strokes are wider on one or both of the ends.
       *  We either identify the stems on the ends as serifs or remove
       *  the linkage, depending on the length of the stems.
       *
       */
  
      {
        AF_Segment  link1, link2;
  
  
        for ( seg1 = segments; seg1 < segment_limit; seg1++ )
        {
          link1 = seg1->link;
          if ( !link1 || link1->link != seg1 || link1->pos <= seg1->pos )
            continue;
  
          if ( seg1->score >= dist_threshold )
            continue;
  
          for ( seg2 = segments; seg2 < segment_limit; seg2++ )
          {
            if ( seg2->pos > seg1->pos || seg1 == seg2 )
              continue;
  
            link2 = seg2->link;
            if ( !link2 || link2->link != seg2 || link2->pos < link1->pos )
              continue;
  
            if ( seg1->pos == seg2->pos && link1->pos == link2->pos )
              continue;
  
            if ( seg2->score <= seg1->score || seg1->score * 4 <= seg2->score )
              continue;
  
            /* seg2 < seg1 < link1 < link2 */
  
            if ( seg1->len >= seg2->len * 3 )
            {
              AF_Segment  seg;
  
  
              for ( seg = segments; seg < segment_limit; seg++ )
              {
                AF_Segment  link = seg->link;
  
  
                if ( link == seg2 )
                {
                  seg->link  = 0;
                  seg->serif = link1;
                }
                else if ( link == link2 )
                {
                  seg->link  = 0;
                  seg->serif = seg1;
                }
              }
            }
            else
            {
              seg1->link = link1->link = 0;
  
              break;
            }
          }
        }
      }
  
      for ( seg1 = segments; seg1 < segment_limit; seg1++ )
      {
        seg2 = seg1->link;
  
        if ( seg2 )
        {
          seg2->num_linked++;
          if ( seg2->link != seg1 )
          {
            seg1->link = 0;
  
            if ( seg2->score < dist_threshold || seg1->score < seg2->score * 4 )
              seg1->serif = seg2->link;
            else
              seg2->num_linked--;
          }
        }
      }
    }
  
  
    static FT_Error
    af_cjk_hints_compute_edges( AF_GlyphHints  hints,
                                AF_Dimension   dim )
    {
      AF_AxisHints  axis   = &hints->axis[dim];
      FT_Error      error  = AF_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;
  
      FT_Fixed      scale;
      FT_Pos        edge_distance_threshold;
  
  
      axis->num_edges = 0;
  
      scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
                                           : hints->y_scale;
  
      /*********************************************************************/
      /*                                                                   */
      /* We 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 is then 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 = FT_DivFix( 64 / 4, scale );
      else
        edge_distance_threshold = laxis->edge_distance_threshold;
  
      for ( seg = segments; seg < segment_limit; seg++ )
      {
        AF_Edge  found = 0;
        FT_Pos   best  = 0xFFFFU;
        FT_Int   ee;
  
  
        /* 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;
  
  
          if ( edge->dir != seg->dir )
            continue;
  
          dist = seg->pos - edge->fpos;
          if ( dist < 0 )
            dist = -dist;
  
          if ( dist < edge_distance_threshold && dist < best )
          {
            AF_Segment  link = seg->link;
  
  
            /* check whether all linked segments of the candidate edge */
            /* can make a single edge.                                 */
            if ( link )
            {
              AF_Segment  seg1 = edge->first;
              AF_Segment  link1;
              FT_Pos      dist2 = 0;
  
  
              do
              {
                link1 = seg1->link;
                if ( link1 )
                {
                  dist2 = AF_SEGMENT_DIST( link, link1 );
                  if ( dist2 >= edge_distance_threshold )
                    break;
                }
  
              } while ( ( seg1 = seg1->edge_next ) != edge->first );
  
              if ( dist2 >= edge_distance_threshold )
                continue;
            }
  
            best  = dist;
            found = edge;
          }
        }
  
        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,
                                          (AF_Direction)seg->dir,
                                          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->fpos     = seg->pos;
          edge->opos     = edge->pos = FT_MulFix( seg->pos, scale );
          seg->edge_next = seg;
          edge->dir      = seg->dir;
        }
        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 now compute each edge's properties according to segments */
      /* found on its position.  Basically, these are as follows.          */
      /*                                                                   */
      /*  - 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? */
  
  
          seg = edge->first;
  
          do
          {
            FT_Bool  is_serif;
  
  
            /* check for roundness of segment */
            if ( seg->flags & AF_EDGE_ROUND )
              is_round++;
            else
              is_straight++;
  
            /* check for links -- if seg->serif is set, then seg->link must */
            /* be ignored                                                   */
            is_serif = (FT_Bool)( seg->serif && seg->serif->edge != edge );
  
            if ( seg->link || 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 = AF_SEGMENT_DIST( seg, seg2 );
  
                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;
  
          /* get 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 = 0;
        }
      }
  
    Exit:
      return error;
    }
  
  
    static FT_Error
    af_cjk_hints_detect_features( AF_GlyphHints  hints,
                                  AF_Dimension   dim )
    {
      FT_Error  error;
  
  
      error = af_cjk_hints_compute_segments( hints, dim );
      if ( !error )
      {
        af_cjk_hints_link_segments( hints, dim );
  
        error = af_cjk_hints_compute_edges( hints, dim );
      }
      return error;
    }
  
  
    FT_LOCAL_DEF( FT_Error )
    af_cjk_hints_init( AF_GlyphHints    hints,
                       AF_LatinMetrics  metrics )
    {
      FT_Render_Mode  mode;
      FT_UInt32       scaler_flags, other_flags;
  
  
      af_glyph_hints_rescale( hints, (AF_ScriptMetrics)metrics );
  
      /*
       *  correct x_scale and y_scale when needed, since they may have
       *  been modified af_cjk_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;
  
  #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 only if we don't use the `light' mode.
       */
      if ( mode != FT_RENDER_MODE_LIGHT )
        other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
  
      if ( mode == FT_RENDER_MODE_MONO )
        other_flags |= AF_LATIN_HINTS_MONO;
  
      scaler_flags |= AF_SCALER_FLAG_NO_ADVANCE;
  
      hints->scaler_flags = scaler_flags;
      hints->other_flags  = other_flags;
  
      return 0;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****          C J K   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_cjk_snap_width( AF_Width  widths,
                       FT_Int    count,
                       FT_Pos    width )
    {
      int     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_cjk_compute_stem_width( AF_GlyphHints  hints,
                               AF_Dimension   dim,
                               FT_Pos         width,
                               AF_Edge_Flags  base_flags,
                               AF_Edge_Flags  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 );
      FT_UNUSED( stem_flags );
  
  
      if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
        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 */
  
        if ( axis->width_count > 0 )
        {
          if ( FT_ABS( dist - axis->widths[0].cur ) < 40 )
          {
            dist = axis->widths[0].cur;
            if ( dist < 48 )
              dist = 48;
  
            goto Done_Width;
          }
        }
  
        if ( dist < 54 )
          dist += ( 54 - dist ) / 2 ;
        else if ( dist < 3 * 64 )
        {
          FT_Pos  delta;
  
  
          delta  = dist & 63;
          dist  &= -64;
  
          if ( delta < 10 )
            dist += delta;
          else if ( delta < 22 )
            dist += 10;
          else if ( delta < 42 )
            dist += delta;
          else if ( delta < 54 )
            dist += 54;
          else
            dist += delta;
        }
      }
      else
      {
        /* strong hinting process: snap the stem width to integer pixels */
  
        dist = af_cjk_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 )
              dist = ( dist + 22 ) & ~63;
            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_cjk_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_cjk_compute_stem_width(
                               hints, dim, dist,
                               (AF_Edge_Flags)base_edge->flags,
                               (AF_Edge_Flags)stem_edge->flags );
  
  
      stem_edge->pos = base_edge->pos + fitted_width;
    }
  
  
    static void
    af_cjk_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                      ****/
    /****                                                                 ****/
    /*************************************************************************/
    /*************************************************************************/
    /*************************************************************************/
  
  
  #define AF_LIGHT_MODE_MAX_HORZ_GAP    9
  #define AF_LIGHT_MODE_MAX_VERT_GAP   15
  #define AF_LIGHT_MODE_MAX_DELTA_ABS  14
  
  
    static FT_Pos
    af_hint_normal_stem( AF_GlyphHints  hints,
                         AF_Edge        edge,
                         AF_Edge        edge2,
                         FT_Pos         anchor,
                         AF_Dimension   dim )
    {
      FT_Pos  org_len, cur_len, org_center;
      FT_Pos  cur_pos1, cur_pos2;
      FT_Pos  d_off1, u_off1, d_off2, u_off2, delta;
      FT_Pos  offset;
      FT_Pos  threshold = 64;
  
  
      if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
      {
        if ( ( edge->flags  & AF_EDGE_ROUND ) &&
             ( edge2->flags & AF_EDGE_ROUND ) )
        {
          if ( dim == AF_DIMENSION_VERT )
            threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP;
          else
            threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP;
        }
        else
        {
          if ( dim == AF_DIMENSION_VERT )
            threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP / 3;
          else
            threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP / 3;
        }
      }
  
      org_len    = edge2->opos - edge->opos;
      cur_len    = af_cjk_compute_stem_width( hints, dim, org_len,
                                              (AF_Edge_Flags)edge->flags,
                                              (AF_Edge_Flags)edge2->flags );
  
      org_center = ( edge->opos + edge2->opos ) / 2 + anchor;
      cur_pos1   = org_center - cur_len / 2;
      cur_pos2   = cur_pos1 + cur_len;
      d_off1     = cur_pos1 - FT_PIX_FLOOR( cur_pos1 );
      d_off2     = cur_pos2 - FT_PIX_FLOOR( cur_pos2 );
      u_off1     = 64 - d_off1;
      u_off2     = 64 - d_off2;
      delta      = 0;
  
  
      if ( d_off1 == 0 || d_off2 == 0 )
        goto Exit;
  
      if ( cur_len <= threshold )
      {
        if ( d_off2 < cur_len )
        {
          if ( u_off1 <= d_off2 )
            delta =  u_off1;
          else
            delta = -d_off2;
        }
  
        goto Exit;
      }
  
      if ( threshold < 64 )
      {
        if ( d_off1 >= threshold || u_off1 >= threshold ||
             d_off2 >= threshold || u_off2 >= threshold )
          goto Exit;
      }
  
      offset = cur_len % 64;
  
      if ( offset < 32 )
      {
        if ( u_off1 <= offset || d_off2 <= offset )
          goto Exit;
      }
      else
        offset = 64 - threshold;
  
      d_off1 = threshold - u_off1;
      u_off1 = u_off1    - offset;
      u_off2 = threshold - d_off2;
      d_off2 = d_off2    - offset;
  
      if ( d_off1 <= u_off1 )
        u_off1 = -d_off1;
  
      if ( d_off2 <= u_off2 )
        u_off2 = -d_off2;
  
      if ( FT_ABS( u_off1 ) <= FT_ABS( u_off2 ) )
        delta = u_off1;
      else
        delta = u_off2;
  
    Exit:
  
  #if 1
      if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
      {
        if ( delta > AF_LIGHT_MODE_MAX_DELTA_ABS )
          delta = AF_LIGHT_MODE_MAX_DELTA_ABS;
        else if ( delta < -AF_LIGHT_MODE_MAX_DELTA_ABS )
          delta = -AF_LIGHT_MODE_MAX_DELTA_ABS;
      }
  #endif
  
      cur_pos1 += delta;
  
      if ( edge->opos < edge2->opos )
      {
        edge->pos  = cur_pos1;
        edge2->pos = cur_pos1 + cur_len;
      }
      else
      {
        edge->pos  = cur_pos1 + cur_len;
        edge2->pos = cur_pos1;
      }
  
      return delta;
    }
  
  
    static void
    af_cjk_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;
      FT_PtrDist    n_edges;
      AF_Edge       edge;
      AF_Edge       anchor   = 0;
      FT_Pos        delta    = 0;
      FT_Int        skipped  = 0;
  
  
      /* now we align all stem edges. */
      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 )
        {
          skipped++;
          continue;
        }
  
        /* now align the stem */
  
        if ( edge2 < edge )
        {
          af_cjk_align_linked_edge( hints, dim, edge2, edge );
          edge->flags |= AF_EDGE_DONE;
          continue;
        }
  
        if ( dim != AF_DIMENSION_VERT && !anchor )
        {
  
  #if 0
          if ( fixedpitch )
          {
            AF_Edge     left  = edge;
            AF_Edge     right = edge_limit - 1;
            AF_EdgeRec  left1, left2, right1, right2;
            FT_Pos      target, center1, center2;
            FT_Pos      delta1, delta2, d1, d2;
  
  
            while ( right > left && !right->link )
              right--;
  
            left1  = *left;
            left2  = *left->link;
            right1 = *right->link;
            right2 = *right;
  
            delta  = ( ( ( hinter->pp2.x + 32 ) & -64 ) - hinter->pp2.x ) / 2;
            target = left->opos + ( right->opos - left->opos ) / 2 + delta - 16;
  
            delta1  = delta;
            delta1 += af_hint_normal_stem( hints, left, left->link,
                                           delta1, 0 );
  
            if ( left->link != right )
              af_hint_normal_stem( hints, right->link, right, delta1, 0 );
  
            center1 = left->pos + ( right->pos - left->pos ) / 2;
  
            if ( center1 >= target )
              delta2 = delta - 32;
            else
              delta2 = delta + 32;
  
            delta2 += af_hint_normal_stem( hints, &left1, &left2, delta2, 0 );
  
            if ( delta1 != delta2 )
            {
              if ( left->link != right )
                af_hint_normal_stem( hints, &right1, &right2, delta2, 0 );
  
              center2 = left1.pos + ( right2.pos - left1.pos ) / 2;
  
              d1 = center1 - target;
              d2 = center2 - target;
  
              if ( FT_ABS( d2 ) < FT_ABS( d1 ) )
              {
                left->pos       = left1.pos;
                left->link->pos = left2.pos;
  
                if ( left->link != right )
                {
                  right->link->pos = right1.pos;
                  right->pos       = right2.pos;
                }
  
                delta1 = delta2;
              }
            }
  
            delta               = delta1;
            right->link->flags |= AF_EDGE_DONE;
            right->flags       |= AF_EDGE_DONE;
          }
          else
  
  #endif /* 0 */
  
            delta = af_hint_normal_stem( hints, edge, edge2, 0,
                                         AF_DIMENSION_HORZ );
        }
        else
          af_hint_normal_stem( hints, edge, edge2, delta, dim );
  
  #if 0
        printf( "stem (%d,%d) adjusted (%.1f,%.1f)\n",
                 edge - edges, edge2 - edges,
                 ( edge->pos - edge->opos ) / 64.0,
                 ( edge2->pos - edge2->opos ) / 64.0 );
  #endif
  
        anchor = edge;
        edge->flags  |= AF_EDGE_DONE;
        edge2->flags |= AF_EDGE_DONE;
      }
  
      /* 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.                                         */
  
      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;
  
  
        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 ( edge1->link == edge1 + 1 &&
             edge2->link == edge2 + 1 &&
             edge3->link == edge3 + 1 && 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;
        }
      }
  
      if ( !skipped )
        return;
  
      /*
       *  now hint the remaining edges (serifs and single) in order
       *  to complete our processing
       */
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        if ( edge->flags & AF_EDGE_DONE )
          continue;
  
        if ( edge->serif )
        {
          af_cjk_align_serif_edge( hints, edge->serif, edge );
          edge->flags |= AF_EDGE_DONE;
          skipped--;
        }
      }
  
      if ( !skipped )
        return;
  
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        AF_Edge  before, after;
  
  
        if ( edge->flags & AF_EDGE_DONE )
          continue;
  
        before = after = edge;
  
        while ( --before >= edges )
          if ( before->flags & AF_EDGE_DONE )
            break;
  
        while ( ++after < edge_limit )
          if ( after->flags & AF_EDGE_DONE )
            break;
  
        if ( before >= edges || after < edge_limit )
        {
          if ( before < edges )
            af_cjk_align_serif_edge( hints, after, edge );
          else if ( after >= edge_limit )
            af_cjk_align_serif_edge( hints, before, edge );
          else
          {
            if ( after->fpos == before->fpos )
              edge->pos = before->pos;
            else
              edge->pos = before->pos +
                          FT_MulDiv( edge->fpos - before->fpos,
                                     after->pos - before->pos,
                                     after->fpos - before->fpos );
          }
        }
      }
    }
  
  
    static void
    af_cjk_align_edge_points( 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;
      FT_Bool       snapping;
  
  
      snapping = FT_BOOL( ( dim == AF_DIMENSION_HORZ             &&
                            AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) )  ||
                          ( dim == AF_DIMENSION_VERT             &&
                            AF_LATIN_HINTS_DO_VERT_SNAP( hints ) )  );
  
      for ( edge = edges; edge < edge_limit; edge++ )
      {
        /* move the points of each segment     */
        /* in each edge to the edge's position */
        AF_Segment  seg = edge->first;
  
  
        if ( snapping )
        {
          do
          {
            AF_Point  point = seg->first;
  
  
            for (;;)
            {
              if ( dim == AF_DIMENSION_HORZ )
              {
                point->x      = edge->pos;
                point->flags |= AF_FLAG_TOUCH_X;
              }
              else
              {
                point->y      = edge->pos;
                point->flags |= AF_FLAG_TOUCH_Y;
              }
  
              if ( point == seg->last )
                break;
  
              point = point->next;
            }
  
            seg = seg->edge_next;
  
          } while ( seg != edge->first );
        }
        else
        {
          FT_Pos  delta = edge->pos - edge->opos;
  
  
          do
          {
            AF_Point  point = seg->first;
  
  
            for (;;)
            {
              if ( dim == AF_DIMENSION_HORZ )
              {
                point->x     += delta;
                point->flags |= AF_FLAG_TOUCH_X;
              }
              else
              {
                point->y     += delta;
                point->flags |= AF_FLAG_TOUCH_Y;
              }
  
              if ( point == seg->last )
                break;
  
              point = point->next;
            }
  
            seg = seg->edge_next;
  
          } while ( seg != edge->first );
        }
      }
    }
  
  
    FT_LOCAL_DEF( FT_Error )
    af_cjk_hints_apply( AF_GlyphHints    hints,
                        FT_Outline*      outline,
                        AF_LatinMetrics  metrics )
    {
      FT_Error  error;
      int       dim;
  
      FT_UNUSED( metrics );
  
  
      error = af_glyph_hints_reload( hints, outline );
      if ( error )
        goto Exit;
  
      /* analyze glyph outline */
      if ( AF_HINTS_DO_HORIZONTAL( hints ) )
      {
        error = af_cjk_hints_detect_features( hints, AF_DIMENSION_HORZ );
        if ( error )
          goto Exit;
      }
  
      if ( AF_HINTS_DO_VERTICAL( hints ) )
      {
        error = af_cjk_hints_detect_features( hints, AF_DIMENSION_VERT );
        if ( error )
          goto Exit;
      }
  
      /* grid-fit the outline */
      for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
      {
        if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
             ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) )   )
        {
  
  #ifdef AF_CONFIG_OPTION_USE_WARPER
          if ( dim == AF_DIMENSION_HORZ                                  &&
               metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL )
          {
            AF_WarperRec  warper;
            FT_Fixed      scale;
            FT_Pos        delta;
  
  
            af_warper_compute( &warper, hints, (AF_Dimension)dim,
                               &scale, &delta );
            af_glyph_hints_scale_dim( hints, (AF_Dimension)dim,
                                      scale, delta );
            continue;
          }
  #endif /* AF_CONFIG_OPTION_USE_WARPER */
  
          af_cjk_hint_edges( hints, (AF_Dimension)dim );
          af_cjk_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 );
        }
      }
  
  #if 0
      af_glyph_hints_dump_points( hints );
      af_glyph_hints_dump_segments( hints );
      af_glyph_hints_dump_edges( hints );
  #endif
  
      af_glyph_hints_save( hints, outline );
  
    Exit:
      return error;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                C J K   S C R I P T   C L A S S                *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  
    static const AF_Script_UniRangeRec  af_cjk_uniranges[] =
    {
  #if 0
      AF_UNIRANGE_REC(  0x0100UL,  0xFFFFUL ),  /* why this? */
  #endif
      AF_UNIRANGE_REC(  0x2E80UL,  0x2EFFUL ),  /* CJK Radicals Supplement                 */
      AF_UNIRANGE_REC(  0x2F00UL,  0x2FDFUL ),  /* Kangxi Radicals                         */
      AF_UNIRANGE_REC(  0x3000UL,  0x303FUL ),  /* CJK Symbols and Punctuation             */
      AF_UNIRANGE_REC(  0x3040UL,  0x309FUL ),  /* Hiragana                                */
      AF_UNIRANGE_REC(  0x30A0UL,  0x30FFUL ),  /* Katakana                                */
      AF_UNIRANGE_REC(  0x3100UL,  0x312FUL ),  /* Bopomofo                                */
      AF_UNIRANGE_REC(  0x3130UL,  0x318FUL ),  /* Hangul Compatibility Jamo               */
      AF_UNIRANGE_REC(  0x31A0UL,  0x31BFUL ),  /* Bopomofo Extended                       */
      AF_UNIRANGE_REC(  0x31C0UL,  0x31EFUL ),  /* CJK Strokes                             */
      AF_UNIRANGE_REC(  0x31F0UL,  0x31FFUL ),  /* Katakana Phonetic Extensions            */
      AF_UNIRANGE_REC(  0x3200UL,  0x32FFUL ),  /* Enclosed CJK Letters and Months         */
      AF_UNIRANGE_REC(  0x3300UL,  0x33FFUL ),  /* CJK Compatibility                       */
      AF_UNIRANGE_REC(  0x3400UL,  0x4DBFUL ),  /* CJK Unified Ideographs Extension A      */
      AF_UNIRANGE_REC(  0x4DC0UL,  0x4DFFUL ),  /* Yijing Hexagram Symbols                 */
      AF_UNIRANGE_REC(  0x4E00UL,  0x9FFFUL ),  /* CJK Unified Ideographs                  */
      AF_UNIRANGE_REC(  0xF900UL,  0xFAFFUL ),  /* CJK Compatibility Ideographs            */
      AF_UNIRANGE_REC(  0xFE30UL,  0xFE4FUL ),  /* CJK Compatibility Forms                 */
      AF_UNIRANGE_REC(  0xFF00UL,  0xFFEFUL ),  /* Halfwidth and Fullwidth Forms           */
      AF_UNIRANGE_REC( 0x20000UL, 0x2A6DFUL ),  /* CJK Unified Ideographs Extension B      */
      AF_UNIRANGE_REC( 0x2F800UL, 0x2FA1FUL ),  /* CJK Compatibility Ideographs Supplement */
      AF_UNIRANGE_REC(       0UL,       0UL )
    };
  
  
    AF_DEFINE_SCRIPT_CLASS(af_cjk_script_class,
      AF_SCRIPT_CJK,
      af_cjk_uniranges,
  
      sizeof( AF_LatinMetricsRec ),
  
      (AF_Script_InitMetricsFunc) af_cjk_metrics_init,
      (AF_Script_ScaleMetricsFunc)af_cjk_metrics_scale,
      (AF_Script_DoneMetricsFunc) NULL,
  
      (AF_Script_InitHintsFunc)   af_cjk_hints_init,
      (AF_Script_ApplyHintsFunc)  af_cjk_hints_apply
    )
  
  #else /* !AF_CONFIG_OPTION_CJK */
  
    static const AF_Script_UniRangeRec  af_cjk_uniranges[] =
    {
      AF_UNIRANGE_REC( 0UL, 0UL )
    };
  
  
    AF_DEFINE_SCRIPT_CLASS(af_cjk_script_class,
      AF_SCRIPT_CJK,
      af_cjk_uniranges,
  
      sizeof( AF_LatinMetricsRec ),
  
      (AF_Script_InitMetricsFunc) NULL,
      (AF_Script_ScaleMetricsFunc)NULL,
      (AF_Script_DoneMetricsFunc) NULL,
  
      (AF_Script_InitHintsFunc)   NULL,
      (AF_Script_ApplyHintsFunc)  NULL
    )
  
  #endif /* !AF_CONFIG_OPTION_CJK */
  
  
  /* END */
  

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