kc3-lang/freetype/src/pshinter/pshalgo3.c

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• Hash : 27c322e9
  Author :
  Date : 2002-07-08T22:26:11
  

  * include/freetype/freetype.h, src/base/ftobjs.h, freetype/internal/ftobjs.h, freetype/internal/psaux.h, freetype/internal/pshints.h, src/psaux/t1decode.c, src/cff/cffgload.h, src/cff/cffgload.c, src/pshinter/pshalgo1.h, src/pshinter/pshalgo1.c, src/pshinter/pshalgo2.h, src/pshinter/pshalgo2.c, src/pshinter/pshalgo3.h, src/pshinter/pshalgo3.c: Adding support for hinter-specific bit flags, and the new FT_Set_Hint_Flags high-level API

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• src/pshinter/pshalgo3.c

• /***************************************************************************/
  /*                                                                         */
  /*  pshalgo3.c                                                             */
  /*                                                                         */
  /*    PostScript hinting algorithm 3 (body).                               */
  /*                                                                         */
  /*  Copyright 2001, 2002 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 <ft2build.h>
  #include FT_INTERNAL_OBJECTS_H
  #include FT_INTERNAL_DEBUG_H
  #include "pshalgo3.h"
  
  #undef  FT_COMPONENT
  #define FT_COMPONENT  trace_pshalgo2
  
  #ifdef DEBUG_HINTER
    extern PSH3_Hint_Table  ps3_debug_hint_table = 0;
    extern PSH3_HintFunc    ps3_debug_hint_func  = 0;
    extern PSH3_Glyph       ps3_debug_glyph      = 0;
  #endif
  
  
  
  #undef  SNAP_STEMS
  #undef  ONLY_ALIGN_Y
  
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                  BASIC HINTS RECORDINGS                       *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    /* return true iff two stem hints overlap */
    static FT_Int
    psh3_hint_overlap( PSH3_Hint  hint1,
                       PSH3_Hint  hint2 )
    {
      return ( hint1->org_pos + hint1->org_len >= hint2->org_pos &&
               hint2->org_pos + hint2->org_len >= hint1->org_pos );
    }
  
  
    /* destroy hints table */
    static void
    psh3_hint_table_done( PSH3_Hint_Table  table,
                          FT_Memory        memory )
    {
      FT_FREE( table->zones );
      table->num_zones = 0;
      table->zone      = 0;
  
      FT_FREE( table->sort );
      FT_FREE( table->hints );
      table->num_hints   = 0;
      table->max_hints   = 0;
      table->sort_global = 0;
    }
  
  
    /* deactivate all hints in a table */
    static void
    psh3_hint_table_deactivate( PSH3_Hint_Table  table )
    {
      FT_UInt   count = table->max_hints;
      PSH3_Hint  hint  = table->hints;
  
  
      for ( ; count > 0; count--, hint++ )
      {
        psh3_hint_deactivate( hint );
        hint->order = -1;
      }
    }
  
  
    /* internal function used to record a new hint */
    static void
    psh3_hint_table_record( PSH3_Hint_Table  table,
                            FT_UInt          idx )
    {
      PSH3_Hint  hint = table->hints + idx;
  
  
      if ( idx >= table->max_hints )
      {
        FT_ERROR(( "%s.activate: invalid hint index %d\n", idx ));
        return;
      }
  
      /* ignore active hints */
      if ( psh3_hint_is_active( hint ) )
        return;
  
      psh3_hint_activate( hint );
  
      /* now scan the current active hint set in order to determine */
      /* if we are overlapping with another segment                 */
      {
        PSH3_Hint*  sorted = table->sort_global;
        FT_UInt     count  = table->num_hints;
        PSH3_Hint   hint2;
  
  
        hint->parent = 0;
        for ( ; count > 0; count--, sorted++ )
        {
          hint2 = sorted[0];
  
          if ( psh3_hint_overlap( hint, hint2 ) )
          {
            hint->parent = hint2;
            break;
          }
        }
      }
  
      if ( table->num_hints < table->max_hints )
        table->sort_global[table->num_hints++] = hint;
      else
        FT_ERROR(( "%s.activate: too many sorted hints!  BUG!\n",
                   "ps.fitter" ));
    }
  
  
    static void
    psh3_hint_table_record_mask( PSH3_Hint_Table  table,
                                 PS_Mask          hint_mask )
    {
      FT_Int    mask = 0, val = 0;
      FT_Byte*  cursor = hint_mask->bytes;
      FT_UInt   idx, limit;
  
  
      limit = hint_mask->num_bits;
  
      for ( idx = 0; idx < limit; idx++ )
      {
        if ( mask == 0 )
        {
          val  = *cursor++;
          mask = 0x80;
        }
  
        if ( val & mask )
          psh3_hint_table_record( table, idx );
  
        mask >>= 1;
      }
    }
  
  
    /* create hints table */
    static FT_Error
    psh3_hint_table_init( PSH3_Hint_Table  table,
                          PS_Hint_Table    hints,
                          PS_Mask_Table    hint_masks,
                          PS_Mask_Table    counter_masks,
                          FT_Memory        memory )
    {
      FT_UInt   count = hints->num_hints;
      FT_Error  error;
  
      FT_UNUSED( counter_masks );
  
  
      /* allocate our tables */
      if ( FT_NEW_ARRAY( table->sort,  2 * count     ) ||
           FT_NEW_ARRAY( table->hints,     count     ) ||
           FT_NEW_ARRAY( table->zones, 2 * count + 1 ) )
        goto Exit;
  
      table->max_hints   = count;
      table->sort_global = table->sort + count;
      table->num_hints   = 0;
      table->num_zones   = 0;
      table->zone        = 0;
  
      /* now, initialize the "hints" array */
      {
        PSH3_Hint  write = table->hints;
        PS_Hint    read  = hints->hints;
  
  
        for ( ; count > 0; count--, write++, read++ )
        {
          write->org_pos = read->pos;
          write->org_len = read->len;
          write->flags   = read->flags;
        }
      }
  
      /* we now need to determine the initial "parent" stems; first  */
      /* activate the hints that are given by the initial hint masks */
      if ( hint_masks )
      {
        FT_UInt  Count = hint_masks->num_masks;
        PS_Mask  Mask  = hint_masks->masks;
  
  
        table->hint_masks = hint_masks;
  
        for ( ; Count > 0; Count--, Mask++ )
          psh3_hint_table_record_mask( table, Mask );
      }
  
      /* now, do a linear parse in case some hints were left alone */
      if ( table->num_hints != table->max_hints )
      {
        FT_UInt   Index, Count;
  
  
        FT_ERROR(( "%s.init: missing/incorrect hint masks!\n" ));
        Count = table->max_hints;
        for ( Index = 0; Index < Count; Index++ )
          psh3_hint_table_record( table, Index );
      }
  
    Exit:
      return error;
    }
  
  
    static void
    psh3_hint_table_activate_mask( PSH3_Hint_Table  table,
                                   PS_Mask          hint_mask )
    {
      FT_Int    mask = 0, val = 0;
      FT_Byte*  cursor = hint_mask->bytes;
      FT_UInt   idx, limit, count;
  
  
      limit = hint_mask->num_bits;
      count = 0;
  
      psh3_hint_table_deactivate( table );
  
      for ( idx = 0; idx < limit; idx++ )
      {
        if ( mask == 0 )
        {
          val  = *cursor++;
          mask = 0x80;
        }
  
        if ( val & mask )
        {
          PSH3_Hint  hint = &table->hints[idx];
  
  
          if ( !psh3_hint_is_active( hint ) )
          {
            FT_UInt     count2;
  
  #if 0
            PSH3_Hint*  sort = table->sort;
            PSH3_Hint   hint2;
  
            for ( count2 = count; count2 > 0; count2--, sort++ )
            {
              hint2 = sort[0];
              if ( psh3_hint_overlap( hint, hint2 ) )
                FT_ERROR(( "%s.activate_mask: found overlapping hints\n",
                           "psf.hint" ));
            }
  #else
            count2 = 0;
  #endif
  
            if ( count2 == 0 )
            {
              psh3_hint_activate( hint );
              if ( count < table->max_hints )
                table->sort[count++] = hint;
              else
                FT_ERROR(( "%s.activate_mask: too many active hints\n",
                           "psf.hint" ));
            }
          }
        }
  
        mask >>= 1;
      }
      table->num_hints = count;
  
      /* now, sort the hints; they are guaranteed to not overlap */
      /* so we can compare their "org_pos" field directly        */
      {
        FT_Int      i1, i2;
        PSH3_Hint   hint1, hint2;
        PSH3_Hint*  sort = table->sort;
  
  
        /* a simple bubble sort will do, since in 99% of cases, the hints */
        /* will be already sorted -- and the sort will be linear          */
        for ( i1 = 1; i1 < (FT_Int)count; i1++ )
        {
          hint1 = sort[i1];
          for ( i2 = i1 - 1; i2 >= 0; i2-- )
          {
            hint2 = sort[i2];
  
            if ( hint2->org_pos < hint1->org_pos )
              break;
  
            sort[i2 + 1] = hint2;
            sort[i2]     = hint1;
          }
        }
      }
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****               HINTS GRID-FITTING AND OPTIMIZATION             *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  #ifdef DEBUG_HINTER
    static void
    ps3_simple_scale( PSH3_Hint_Table  table,
                      FT_Fixed         scale,
                      FT_Fixed         delta,
                      FT_Int           dimension )
    {
      PSH3_Hint  hint;
      FT_UInt    count;
  
  
      for ( count = 0; count < table->max_hints; count++ )
      {
        hint = table->hints + count;
  
        hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta;
        hint->cur_len = FT_MulFix( hint->org_len, scale );
  
        if ( ps3_debug_hint_func )
          ps3_debug_hint_func( hint, dimension );
      }
    }
  #endif
  
    static FT_Fixed
    psh3_hint_snap_stem_side_delta ( FT_Fixed pos,
                                     FT_Fixed len )
    {
      FT_Fixed delta1 = ( ( pos + 32 ) & -64 ) - pos;
      FT_Fixed delta2 = ( ( pos + len + 32 ) & -64  ) - pos - len;
  
      if ( ABS( delta1 ) <= ABS( delta2 ) )
      {
        return delta1;
      }
      else
      {
        return delta2;
      }
    }
  
  
    static void
    psh3_hint_align( PSH3_Hint    hint,
                     PSH_Globals  globals,
                     FT_Int       dimension,
                     FT_UInt32    hint_flags )
    {
      PSH_Dimension  dim   = &globals->dimension[dimension];
      FT_Fixed       scale = dim->scale_mult;
      FT_Fixed       delta = dim->scale_delta;
  
  
      if ( !psh3_hint_is_fitted(hint) )
      {
        FT_Pos  pos = FT_MulFix( hint->org_pos, scale ) + delta;
        FT_Pos  len = FT_MulFix( hint->org_len, scale );
  
        FT_Pos            fit_center;
        FT_Pos            fit_len;
        PSH_AlignmentRec  align;
  
  
        /* ignore stem alignments when requested through the hint flags */
        if ( ( dimension == 0 && ( hint_flags & FT_HINT_NO_VSTEM_ALIGN ) != 0 ) ||
             ( dimension == 1 && ( hint_flags & FT_HINT_NO_HSTEM_ALIGN ) != 0 ) )
        {
          hint->cur_pos = pos;
          hint->cur_len = len;
  
          psh3_hint_set_fitted( hint );
          return;
            }
  
        /* perform stem snapping when requested */
        if ( ( hint_flags & FT_HINT_NO_INTEGER_STEM ) == 0 )
        {
          /* compute fitted width/height */
          fit_len = 0;
          if ( hint->org_len )
          {
            fit_len = psh_dimension_snap_width( dim, hint->org_len );
            if ( fit_len < 64 )
              fit_len = 64;
            else
              fit_len = ( fit_len + 32 ) & -64;
          }
        }
        else
          fit_len = len;
  
        hint->cur_len = fit_len;
  
        /* check blue zones for horizontal stems */
        align.align = PSH_BLUE_ALIGN_NONE;
        align.align_bot = align.align_top = 0;
  
        if ( dimension == 1 )
          psh_blues_snap_stem( &globals->blues,
                               hint->org_pos + hint->org_len,
                               hint->org_pos,
                               &align );
  
        switch ( align.align )
        {
        case PSH_BLUE_ALIGN_TOP:
          /* the top of the stem is aligned against a blue zone */
          hint->cur_pos = align.align_top - fit_len;
          break;
  
        case PSH_BLUE_ALIGN_BOT:
          /* the bottom of the stem is aligned against a blue zone */
          hint->cur_pos = align.align_bot;
          break;
  
        case PSH_BLUE_ALIGN_TOP | PSH_BLUE_ALIGN_BOT:
          /* both edges of the stem are aligned against blue zones */
          hint->cur_pos = align.align_bot;
          hint->cur_len = align.align_top - align.align_bot;
          break;
  
        default:
          {
            PSH3_Hint  parent = hint->parent;
  
  
            if ( parent )
            {
              FT_Pos  par_org_center, par_cur_center;
              FT_Pos  cur_org_center, cur_delta;
  
  
              /* ensure that parent is already fitted */
              if ( !psh3_hint_is_fitted( parent ) )
                psh3_hint_align( parent, globals, dimension, hint_flags );
  
              par_org_center = parent->org_pos + ( parent->org_len / 2);
              par_cur_center = parent->cur_pos + ( parent->cur_len / 2);
              cur_org_center = hint->org_pos   + ( hint->org_len   / 2);
  
              cur_delta = FT_MulFix( cur_org_center - par_org_center, scale );
              pos       = par_cur_center + cur_delta - ( len >> 1 );
            }
  
            if ( ( hint_flags & FT_HINT_NO_INTEGER_STEM ) == 0 )
            {
              /* normal processing */
              if ( ( fit_len / 64 ) & 1 )
              {
                /* odd number of pixels */
                fit_center = ( ( pos + ( len >> 1 ) ) & -64 ) + 32;
              }
              else
              {
                /* even number of pixels */
                fit_center = ( pos + ( len >> 1 ) + 32 ) & -64;
              }
              hint->cur_pos = fit_center - ( fit_len >> 1 );
            }
            else
            {
              /* Stems less than one pixel wide are easy - we want to
               * make them as dark as possible, so they must fall within
               * one pixel. If the stem is split between two pixels
               * then snap the edge that is nearer to the pixel boundary
               * to the pixel boundary
               */
              if (len <= 64)
              {
                if ( ( pos + len + 63 ) / 64  != pos / 64 + 1 )
                  pos += psh3_hint_snap_stem_side_delta ( pos, len );
              }
              /* Position stems other to minimize the amount of mid-grays.
               * There are, in general, two positions that do this,
               * illustrated as A) and B) below.
               *
               *   +                   +                   +                   +
               *
               * A)             |--------------------------------|
               * B)   |--------------------------------|
               * C)       |--------------------------------|
               *
               * Position A) (split the excess stem equally) should be better
               * for stems of width N + f where f < 0.5
               *
               * Position B) (split the deficiency equally) should be better
               * for stems of width N + f where f > 0.5
               *
               * It turns out though that minimizing the total number of touched
               * pixels is also important, so position C), with one edge
               * aligned with a pixel boundary is actually preferable
               * to A). There are also more possible positions for C) than
               * for A) or B), so there will be less distortion of the overall
               * character shape.
               */
              else
              {
                FT_Fixed frac_len = len & 63;
                FT_Fixed center = pos + ( len >> 1 );
  
                FT_Fixed delta_a, delta_b;
  
                if ( ( len / 64 ) & 1 )
                {
                  delta_a = ( center & -64 ) + 32 - center;
                  delta_b = ( ( center + 32 ) & - 64 ) - center;
                }
                else
                {
                  delta_a = ( ( center + 32 ) & - 64 ) - center;
                  delta_b = ( center & -64 ) + 32 - center;
                }
  
                /* We choose between B) and C) above based on the amount
                 * of fractional stem width: for small amounts, choose
                 * C) always; for large amounts, B) always; inbetween,
                 * pick whichever one involves less stem movement.
                 */
                if (frac_len < 32)
                {
                  pos += psh3_hint_snap_stem_side_delta ( pos, len );
                }
                else if (frac_len < 48)
                {
                  FT_Fixed side_delta = psh3_hint_snap_stem_side_delta ( pos, len );
  
                  if ( ABS( side_delta ) < ABS( delta_b ) )
                    pos += side_delta;
                  else
                    pos += delta_b;
                }
                else
                {
                  pos += delta_b;
                }
              }
              hint->cur_pos = pos;
            }
          }
        }
  
        psh3_hint_set_fitted( hint );
  
  #ifdef DEBUG_HINTER
        if ( ps3_debug_hint_func )
          ps3_debug_hint_func( hint, dimension );
  #endif
      }
    }
  
  
    static void
    psh3_hint_table_align_hints( PSH3_Hint_Table  table,
                                 PSH_Globals      globals,
                                 FT_Int           dimension,
                                 FT_UInt32        hint_flags )
    {
      PSH3_Hint      hint;
      FT_UInt        count;
  
  #ifdef DEBUG_HINTER
      PSH_Dimension  dim   = &globals->dimension[dimension];
      FT_Fixed       scale = dim->scale_mult;
      FT_Fixed       delta = dim->scale_delta;
  
  
      if ( ps_debug_no_vert_hints && dimension == 0 )
      {
        ps3_simple_scale( table, scale, delta, dimension );
        return;
      }
  
      if ( ps_debug_no_horz_hints && dimension == 1 )
      {
        ps3_simple_scale( table, scale, delta, dimension );
        return;
      }
  #endif
  
      hint  = table->hints;
      count = table->max_hints;
  
      for ( ; count > 0; count--, hint++ )
        psh3_hint_align( hint, globals, dimension, hint_flags );
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                POINTS INTERPOLATION ROUTINES                  *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  #define PSH3_ZONE_MIN  -3200000
  #define PSH3_ZONE_MAX  +3200000
  
  #define xxDEBUG_ZONES
  
  
  #ifdef DEBUG_ZONES
  
  #include <stdio.h>
  
    static void
    psh3_print_zone( PSH3_Zone  zone )
    {
      printf( "zone [scale,delta,min,max] = [%.3f,%.3f,%d,%d]\n",
               zone->scale/65536.0,
               zone->delta/64.0,
               zone->min,
               zone->max );
    }
  
  #else
  
  #define psh3_print_zone( x )   do { } while ( 0 )
  
  #endif
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                    HINTER GLYPH MANAGEMENT                    *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    static int
    psh3_point_is_extremum( PSH3_Point  point )
    {
      PSH3_Point  before = point;
      PSH3_Point  after  = point;
      FT_Pos      d_before;
      FT_Pos      d_after;
  
  
      do
      {
        before = before->prev;
        if ( before == point )
          return 0;
  
        d_before = before->org_u - point->org_u;
  
      } while ( d_before == 0 );
  
      do
      {
        after = after->next;
        if ( after == point )
          return 0;
  
        d_after = after->org_u - point->org_u;
  
      } while ( d_after == 0 );
  
      return ( ( d_before > 0 && d_after > 0 ) ||
               ( d_before < 0 && d_after < 0 ) );
    }
  
  
    static void
    psh3_glyph_done( PSH3_Glyph  glyph )
    {
      FT_Memory  memory = glyph->memory;
  
  
      psh3_hint_table_done( &glyph->hint_tables[1], memory );
      psh3_hint_table_done( &glyph->hint_tables[0], memory );
  
      FT_FREE( glyph->points );
      FT_FREE( glyph->contours );
  
      glyph->num_points   = 0;
      glyph->num_contours = 0;
  
      glyph->memory = 0;
    }
  
  
    static int
    psh3_compute_dir( FT_Pos  dx,
                      FT_Pos  dy )
    {
      FT_Pos  ax, ay;
      int     result = PSH3_DIR_NONE;
  
  
      ax = ( dx >= 0 ) ? dx : -dx;
      ay = ( dy >= 0 ) ? dy : -dy;
  
      if ( ay * 12 < ax )
      {
        /* |dy| <<< |dx|  means a near-horizontal segment */
        result = ( dx >= 0 ) ? PSH3_DIR_RIGHT : PSH3_DIR_LEFT;
      }
      else if ( ax * 12 < ay )
      {
        /* |dx| <<< |dy|  means a near-vertical segment */
        result = ( dy >= 0 ) ? PSH3_DIR_UP : PSH3_DIR_DOWN;
      }
  
      return result;
    }
  
  
    static FT_Error
    psh3_glyph_init( PSH3_Glyph   glyph,
                     FT_Outline*  outline,
                     PS_Hints     ps_hints,
                     PSH_Globals  globals )
    {
      FT_Error   error;
      FT_Memory  memory;
  
  
      /* clear all fields */
      ft_memset( glyph, 0, sizeof ( *glyph ) );
  
      memory = globals->memory;
  
      /* allocate and setup points + contours arrays */
      if ( FT_NEW_ARRAY( glyph->points,   outline->n_points   ) ||
           FT_NEW_ARRAY( glyph->contours, outline->n_contours ) )
        goto Exit;
  
      glyph->num_points   = outline->n_points;
      glyph->num_contours = outline->n_contours;
  
      {
        FT_UInt       first = 0, next, n;
        PSH3_Point    points  = glyph->points;
        PSH3_Contour  contour = glyph->contours;
  
  
        for ( n = 0; n < glyph->num_contours; n++ )
        {
          FT_Int      count;
          PSH3_Point  point;
  
  
          next  = outline->contours[n] + 1;
          count = next - first;
  
          contour->start = points + first;
          contour->count = (FT_UInt)count;
  
          if ( count > 0 )
          {
            point = points + first;
  
            point->prev    = points + next - 1;
            point->contour = contour;
  
            for ( ; count > 1; count-- )
            {
              point[0].next = point + 1;
              point[1].prev = point;
              point++;
              point->contour = contour;
            }
            point->next = points + first;
          }
  
          contour++;
          first = next;
        }
      }
  
      {
        PSH3_Point  points = glyph->points;
        PSH3_Point  point  = points;
        FT_Vector*  vec    = outline->points;
        FT_UInt     n;
  
  
        for ( n = 0; n < glyph->num_points; n++, point++ )
        {
          FT_Int  n_prev = point->prev - points;
          FT_Int  n_next = point->next - points;
          FT_Pos  dxi, dyi, dxo, dyo;
  
  
          if ( !( outline->tags[n] & FT_Curve_Tag_On ) )
            point->flags = PSH3_POINT_OFF;
  
          dxi = vec[n].x - vec[n_prev].x;
          dyi = vec[n].y - vec[n_prev].y;
  
          point->dir_in = (FT_Char)psh3_compute_dir( dxi, dyi );
  
          dxo = vec[n_next].x - vec[n].x;
          dyo = vec[n_next].y - vec[n].y;
  
          point->dir_out = (FT_Char)psh3_compute_dir( dxo, dyo );
  
          /* detect smooth points */
          if ( point->flags & PSH3_POINT_OFF )
            point->flags |= PSH3_POINT_SMOOTH;
          else if ( point->dir_in  != PSH3_DIR_NONE ||
                    point->dir_out != PSH3_DIR_NONE )
          {
            if ( point->dir_in == point->dir_out )
              point->flags |= PSH3_POINT_SMOOTH;
          }
          else
          {
            FT_Angle  angle_in, angle_out, diff;
  
  
            angle_in  = FT_Atan2( dxi, dyi );
            angle_out = FT_Atan2( dxo, dyo );
  
            diff = angle_in - angle_out;
            if ( diff < 0 )
              diff = -diff;
  
            if ( diff > FT_ANGLE_PI )
              diff = FT_ANGLE_2PI - diff;
  
            if ( diff < FT_ANGLE_PI / 16 )
              point->flags |= PSH3_POINT_SMOOTH;
          }
        }
      }
  
      glyph->memory  = memory;
      glyph->outline = outline;
      glyph->globals = globals;
  
      /* now deal with hints tables */
      error = psh3_hint_table_init( &glyph->hint_tables [0],
                                    &ps_hints->dimension[0].hints,
                                    &ps_hints->dimension[0].masks,
                                    &ps_hints->dimension[0].counters,
                                    memory );
      if ( error )
        goto Exit;
  
      error = psh3_hint_table_init( &glyph->hint_tables [1],
                                    &ps_hints->dimension[1].hints,
                                    &ps_hints->dimension[1].masks,
                                    &ps_hints->dimension[1].counters,
                                    memory );
      if ( error )
        goto Exit;
  
    Exit:
      return error;
    }
  
  
    /* load outline point coordinates into hinter glyph */
    static void
    psh3_glyph_load_points( PSH3_Glyph  glyph,
                            FT_Int      dimension )
    {
      FT_Vector*  vec   = glyph->outline->points;
      PSH3_Point  point = glyph->points;
      FT_UInt     count = glyph->num_points;
  
  
      for ( ; count > 0; count--, point++, vec++ )
      {
        point->flags &= PSH3_POINT_OFF | PSH3_POINT_SMOOTH;
        point->hint   = 0;
        if ( dimension == 0 )
          point->org_u = vec->x;
        else
          point->org_u = vec->y;
  
  #ifdef DEBUG_HINTER
        point->org_x = vec->x;
        point->org_y = vec->y;
  #endif
      }
    }
  
  
    /* save hinted point coordinates back to outline */
    static void
    psh3_glyph_save_points( PSH3_Glyph  glyph,
                            FT_Int      dimension )
    {
      FT_UInt     n;
      PSH3_Point  point = glyph->points;
      FT_Vector*  vec   = glyph->outline->points;
      char*       tags  = glyph->outline->tags;
  
  
      for ( n = 0; n < glyph->num_points; n++ )
      {
        if ( dimension == 0 )
          vec[n].x = point->cur_u;
        else
          vec[n].y = point->cur_u;
  
        if ( psh3_point_is_strong( point ) )
          tags[n] |= (char)( ( dimension == 0 ) ? 32 : 64 );
  
  #ifdef DEBUG_HINTER
        if ( dimension == 0 )
        {
          point->cur_x   = point->cur_u;
          point->flags_x = point->flags;
        }
        else
        {
          point->cur_y   = point->cur_u;
          point->flags_y = point->flags;
        }
  #endif
        point++;
      }
    }
  
  
  #define PSH3_STRONG_THRESHOLD  10
  
  
    static void
    psh3_hint_table_find_strong_point( PSH3_Hint_Table  table,
                                       PSH3_Point       point,
                                       FT_Int           major_dir )
    {
      PSH3_Hint*   sort      = table->sort;
      FT_UInt      num_hints = table->num_hints;
  
  
      for ( ; num_hints > 0; num_hints--, sort++ )
      {
        PSH3_Hint  hint = sort[0];
  
  
        if ( ABS( point->dir_in )  == major_dir ||
             ABS( point->dir_out ) == major_dir )
        {
          FT_Pos  d;
  
  
          d = point->org_u - hint->org_pos;
          if ( ABS( d ) < PSH3_STRONG_THRESHOLD )
          {
          Is_Strong:
            psh3_point_set_strong( point );
            point->hint = hint;
            break;
          }
  
          d -= hint->org_len;
          if ( ABS( d ) < PSH3_STRONG_THRESHOLD )
            goto Is_Strong;
        }
  
  #if 1
        if ( point->org_u >= hint->org_pos &&
             point->org_u <= hint->org_pos + hint->org_len &&
             psh3_point_is_extremum( point ) )
        {
          /* attach to hint, but don't mark as strong */
          point->hint = hint;
          break;
        }
  #endif
      }
    }
  
  
    /* find strong points in a glyph */
    static void
    psh3_glyph_find_strong_points( PSH3_Glyph  glyph,
                                   FT_Int      dimension )
    {
      /* a point is strong if it is located on a stem                   */
      /* edge and has an "in" or "out" tangent to the hint's direction  */
      {
        PSH3_Hint_Table  table     = &glyph->hint_tables[dimension];
        PS_Mask          mask      = table->hint_masks->masks;
        FT_UInt          num_masks = table->hint_masks->num_masks;
        FT_UInt          first     = 0;
        FT_Int           major_dir = dimension == 0 ? PSH3_DIR_UP : PSH3_DIR_RIGHT;
  
  
        /* process secondary hints to "selected" points */
        if ( num_masks > 1 )
        {
          first = mask->end_point;
          mask++;
          for ( ; num_masks > 1; num_masks--, mask++ )
          {
            FT_UInt  next;
            FT_Int   count;
  
  
            next  = mask->end_point;
            count = next - first;
            if ( count > 0 )
            {
              PSH3_Point  point = glyph->points + first;
  
  
              psh3_hint_table_activate_mask( table, mask );
  
              for ( ; count > 0; count--, point++ )
                psh3_hint_table_find_strong_point( table, point, major_dir );
            }
            first = next;
          }
        }
  
        /* process primary hints for all points */
        if ( num_masks == 1 )
        {
          FT_UInt     count = glyph->num_points;
          PSH3_Point  point = glyph->points;
  
  
          psh3_hint_table_activate_mask( table, table->hint_masks->masks );
          for ( ; count > 0; count--, point++ )
          {
            if ( !psh3_point_is_strong( point ) )
              psh3_hint_table_find_strong_point( table, point, major_dir );
          }
        }
  
        /* now, certain points may have been attached to hint and */
        /* not marked as strong; update their flags then          */
        {
          FT_UInt     count = glyph->num_points;
          PSH3_Point  point = glyph->points;
  
  
          for ( ; count > 0; count--, point++ )
            if ( point->hint && !psh3_point_is_strong( point ) )
              psh3_point_set_strong( point );
        }
      }
    }
  
  
    /* interpolate strong points with the help of hinted coordinates */
    static void
    psh3_glyph_interpolate_strong_points( PSH3_Glyph  glyph,
                                          FT_Int      dimension )
    {
      PSH_Dimension    dim   = &glyph->globals->dimension[dimension];
      FT_Fixed         scale = dim->scale_mult;
  
  
      {
        FT_UInt     count = glyph->num_points;
        PSH3_Point  point = glyph->points;
  
  
        for ( ; count > 0; count--, point++ )
        {
          PSH3_Hint  hint = point->hint;
  
  
          if ( hint )
          {
            FT_Pos  delta;
  
  
            delta = point->org_u - hint->org_pos;
  
            if ( delta <= 0 )
              point->cur_u = hint->cur_pos + FT_MulFix( delta, scale );
  
            else if ( delta >= hint->org_len )
              point->cur_u = hint->cur_pos + hint->cur_len +
                             FT_MulFix( delta - hint->org_len, scale );
  
            else if ( hint->org_len > 0 )
              point->cur_u = hint->cur_pos +
                             FT_MulDiv( delta, hint->cur_len, hint->org_len );
            else
              point->cur_u = hint->cur_pos;
  
            psh3_point_set_fitted( point );
          }
        }
      }
    }
  
  
    static void
    psh3_glyph_interpolate_normal_points( PSH3_Glyph  glyph,
                                          FT_Int      dimension )
    {
  #if 1
      PSH_Dimension    dim   = &glyph->globals->dimension[dimension];
      FT_Fixed         scale = dim->scale_mult;
  
  
      /* first technique: a point is strong if it is a local extrema */
      {
        FT_UInt     count = glyph->num_points;
        PSH3_Point  point = glyph->points;
  
  
        for ( ; count > 0; count--, point++ )
        {
          if ( psh3_point_is_strong( point ) )
            continue;
  
          /* sometimes, some local extremas are smooth points */
          if ( psh3_point_is_smooth( point ) )
          {
            if ( point->dir_in == PSH3_DIR_NONE  ||
                 point->dir_in != point->dir_out )
              continue;
  
            if ( !psh3_point_is_extremum( point ) )
              continue;
  
            point->flags &= ~PSH3_POINT_SMOOTH;
          }
  
          /* find best enclosing point coordinates */
          {
            PSH3_Point  before = 0;
            PSH3_Point  after  = 0;
  
            FT_Pos      diff_before = -32000;
            FT_Pos      diff_after  =  32000;
            FT_Pos      u = point->org_u;
  
            FT_Int      count2 = glyph->num_points;
            PSH3_Point  cur    = glyph->points;
  
  
            for ( ; count2 > 0; count2--, cur++ )
            {
              if ( psh3_point_is_strong( cur ) )
              {
                FT_Pos   diff = cur->org_u - u;;
  
  
                if ( diff <= 0 )
                {
                  if ( diff > diff_before )
                  {
                    diff_before = diff;
                    before      = cur;
                  }
                }
                else if ( diff >= 0 )
                {
                  if ( diff < diff_after )
                  {
                    diff_after = diff;
                    after      = cur;
                  }
                }
              }
            }
  
            if ( !before )
            {
              if ( !after )
                continue;
  
              /* we are before the first strong point coordinate; */
              /* simply translate the point                       */
              point->cur_u = after->cur_u +
                             FT_MulFix( point->org_u - after->org_u, scale );
            }
            else if ( !after )
            {
              /* we are after the last strong point coordinate; */
              /* simply translate the point                     */
              point->cur_u = before->cur_u +
                             FT_MulFix( point->org_u - before->org_u, scale );
            }
            else
            {
              if ( diff_before == 0 )
                point->cur_u = before->cur_u;
  
              else if ( diff_after == 0 )
                point->cur_u = after->cur_u;
  
              else
                point->cur_u = before->cur_u +
                               FT_MulDiv( u - before->org_u,
                                          after->cur_u - before->cur_u,
                                          after->org_u - before->org_u );
            }
  
            psh3_point_set_fitted( point );
          }
        }
      }
  #endif
    }
  
  
    /* interpolate other points */
    static void
    psh3_glyph_interpolate_other_points( PSH3_Glyph  glyph,
                                         FT_Int      dimension )
    {
      PSH_Dimension dim          = &glyph->globals->dimension[dimension];
      FT_Fixed      scale        = dim->scale_mult;
      FT_Fixed      delta        = dim->scale_delta;
      PSH3_Contour  contour      = glyph->contours;
      FT_UInt       num_contours = glyph->num_contours;
  
  
      for ( ; num_contours > 0; num_contours--, contour++ )
      {
        PSH3_Point   start = contour->start;
        PSH3_Point   first, next, point;
        FT_UInt      fit_count;
  
  
        /* count the number of strong points in this contour */
        next      = start + contour->count;
        fit_count = 0;
        first     = 0;
  
        for ( point = start; point < next; point++ )
          if ( psh3_point_is_fitted( point ) )
          {
            if ( !first )
              first = point;
  
            fit_count++;
          }
  
        /* if there are less than 2 fitted points in the contour, we */
        /* simply scale and eventually translate the contour points  */
        if ( fit_count < 2 )
        {
          if ( fit_count == 1 )
            delta = first->cur_u - FT_MulFix( first->org_u, scale );
  
          for ( point = start; point < next; point++ )
            if ( point != first )
              point->cur_u = FT_MulFix( point->org_u, scale ) + delta;
  
          goto Next_Contour;
        }
  
        /* there are more than 2 strong points in this contour; we */
        /* need to interpolate weak points between them            */
        start = first;
        do
        {
          point = first;
  
          /* skip consecutive fitted points */
          for (;;)
          {
            next = first->next;
            if ( next == start )
              goto Next_Contour;
  
            if ( !psh3_point_is_fitted( next ) )
              break;
  
            first = next;
          }
  
          /* find next fitted point after unfitted one */
          for (;;)
          {
            next = next->next;
            if ( psh3_point_is_fitted( next ) )
              break;
          }
  
          /* now interpolate between them */
          {
            FT_Pos    org_a, org_ab, cur_a, cur_ab;
            FT_Pos    org_c, org_ac, cur_c;
            FT_Fixed  scale_ab;
  
  
            if ( first->org_u <= next->org_u )
            {
              org_a  = first->org_u;
              cur_a  = first->cur_u;
              org_ab = next->org_u - org_a;
              cur_ab = next->cur_u - cur_a;
            }
            else
            {
              org_a  = next->org_u;
              cur_a  = next->cur_u;
              org_ab = first->org_u - org_a;
              cur_ab = first->cur_u - cur_a;
            }
  
            scale_ab = 0x10000L;
            if ( org_ab > 0 )
              scale_ab = FT_DivFix( cur_ab, org_ab );
  
            point = first->next;
            do
            {
              org_c  = point->org_u;
              org_ac = org_c - org_a;
  
              if ( org_ac <= 0 )
              {
                /* on the left of the interpolation zone */
                cur_c = cur_a + FT_MulFix( org_ac, scale );
              }
              else if ( org_ac >= org_ab )
              {
                /* on the right on the interpolation zone */
                cur_c = cur_a + cur_ab + FT_MulFix( org_ac - org_ab, scale );
              }
              else
              {
                /* within the interpolation zone */
                cur_c = cur_a + FT_MulFix( org_ac, scale_ab );
              }
  
              point->cur_u = cur_c;
  
              point = point->next;
  
            } while ( point != next );
          }
  
          /* keep going until all points in the contours have been processed */
          first = next;
  
        } while ( first != start );
  
      Next_Contour:
        ;
      }
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                     HIGH-LEVEL INTERFACE                      *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    FT_Error
    ps3_hints_apply( PS_Hints     ps_hints,
                     FT_Outline*  outline,
                     PSH_Globals  globals,
                     FT_UInt32    hint_flags )
    {
      PSH3_GlyphRec  glyphrec;
      PSH3_Glyph     glyph = &glyphrec;
      FT_Error       error;
  #ifdef DEBUG_HINTER
      FT_Memory      memory;
  #endif
      FT_Int         dimension;
  
  
  #ifdef DEBUG_HINTER
      memory = globals->memory;
  
      if ( ps3_debug_glyph )
      {
        psh3_glyph_done( ps3_debug_glyph );
        FT_FREE( ps3_debug_glyph );
      }
  
      if ( FT_NEW( glyph ) )
        return error;
  
      ps3_debug_glyph = glyph;
  #endif
  
      error = psh3_glyph_init( glyph, outline, ps_hints, globals );
      if ( error )
        goto Exit;
  
      for ( dimension = 0; dimension < 2; dimension++ )
      {
        /* load outline coordinates into glyph */
        psh3_glyph_load_points( glyph, dimension );
  
        /* compute aligned stem/hints positions */
        psh3_hint_table_align_hints( &glyph->hint_tables[dimension],
                                     glyph->globals,
                                     dimension,
                                     hint_flags );
  
        /* find strong points, align them, then interpolate others */
        psh3_glyph_find_strong_points( glyph, dimension );
        psh3_glyph_interpolate_strong_points( glyph, dimension );
        psh3_glyph_interpolate_normal_points( glyph, dimension );
        psh3_glyph_interpolate_other_points( glyph, dimension );
  
        /* save hinted coordinates back to outline */
        psh3_glyph_save_points( glyph, dimension );
      }
  
    Exit:
  #ifndef DEBUG_HINTER
      psh3_glyph_done( glyph );
  #endif
      return error;
    }
  
  
  /* END */
  

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