shithub: freetype+ttf2subf

Download patch

ref: 9f7d079c896fe4915caf6b43ee6091691d7c4b5e
parent: 26438805c761ef91eb2dbc21cdf342f077469f22
author: David Turner <[email protected]>
date: Wed Jul 3 17:00:26 EDT 2002

adding Owen Taylor's patches to the Postscript hinter for testing

git/fs: mount .git/fs: mount/attach disallowed
--- a/src/pshinter/Jamfile
+++ b/src/pshinter/Jamfile
@@ -10,7 +10,7 @@
 
   if $(FT2_MULTI)
   {
-    _sources = pshrec pshglob pshalgo1 pshalgo2 pshmod ;
+    _sources = pshrec pshglob pshalgo1 pshalgo2 pshalgo3 pshmod ;
   }
   else
   {
--- a/src/pshinter/pshalgo.h
+++ b/src/pshinter/pshalgo.h
@@ -22,17 +22,26 @@
 FT_BEGIN_HEADER
 
 /* define to choose hinting algorithm */
-#define PSH_ALGORITHM_2
+#define PSH_ALGORITHM_3
 
-#ifdef PSH_ALGORITHM_1
+#if defined(PSH_ALGORITHM_1)
 
-#include "pshalgo1.h"
-#define PS_HINTS_APPLY_FUNC  ps1_hints_apply
+#  include "pshalgo1.h"
+#  define PS_HINTS_APPLY_FUNC  ps1_hints_apply
 
+#elif defined(PSH_ALGORITHM_2)
+
+#  include "pshalgo2.h"
+#  define PS_HINTS_APPLY_FUNC  ps2_hints_apply
+
+#elif defined(PSH_ALGORITHM_3)
+
+#  include "pshalgo3.h"
+#  define PS_HINTS_APPLY_FUNC  ps3_hints_apply
+
 #else
 
-#include "pshalgo2.h"
-#define PS_HINTS_APPLY_FUNC  ps2_hints_apply
+#  error "invalid Postscript Hinter algorithm selection"
 
 #endif
 
--- /dev/null
+++ b/src/pshinter/pshalgo3.c
@@ -1,0 +1,1722 @@
+/***************************************************************************/
+/*                                                                         */
+/*  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 )
+  {
+    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 );
+
+#ifdef SNAP_STEMS
+      FT_Pos  fit_center;
+      FT_Pos  fit_len;
+
+      PSH_AlignmentRec  align;
+
+      /* 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;
+      }
+
+      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 );
+
+            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 );
+#if 0
+            if ( cur_delta >= 0 )
+              cur_delta = ( cur_delta + 16 ) & -64;
+            else
+              cur_delta = -( (-cur_delta + 16 ) & -64 );
+#endif
+            pos = par_cur_center + cur_delta - ( len >> 1 );
+          }
+
+          /* 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
+      PSH_AlignmentRec  align;
+
+      hint->cur_len = 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 );
+#ifdef ONLY_ALIGN_Y
+      else
+      {
+	hint->cur_pos = pos;
+	return;
+      }
+#endif
+      
+      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 - 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 );
+
+            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 );
+          }
+
+          {
+	    /* 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 lit
+	     * pixels is also important, so position C), with one edge
+	     * aligned with a pixel boundary is actually preferable
+	     * to A). There are also more possibile positions for C) than
+	     * for A) or B), so it involves 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 fractinal stem width; for small amounts, choose
+	       * C) always, for large amounts, B) always, and 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;
+	}
+      }
+#endif
+      
+      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 )
+  {
+    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 );
+  }
+
+
+  /*************************************************************************/
+  /*************************************************************************/
+  /*****                                                               *****/
+  /*****                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
+
+#if 0
+  /* setup interpolation zones once the hints have been grid-fitted */
+  /* by the optimizer                                               */
+  static void
+  psh3_hint_table_setup_zones( PSH3_Hint_Table  table,
+                               FT_Fixed         scale,
+                               FT_Fixed         delta )
+  {
+    FT_UInt     count;
+    PSH3_Zone   zone;
+    PSH3_Hint  *sort, hint, hint2;
+
+
+    zone = table->zones;
+
+    /* special case, no hints defined */
+    if ( table->num_hints == 0 )
+    {
+      zone->scale = scale;
+      zone->delta = delta;
+      zone->min   = PSH3_ZONE_MIN;
+      zone->max   = PSH3_ZONE_MAX;
+
+      table->num_zones = 1;
+      table->zone      = zone;
+      return;
+    }
+
+    /* the first zone is before the first hint */
+    /* x' = (x-x0)*s + x0' = x*s + ( x0' - x0*s ) */
+    sort = table->sort;
+    hint = sort[0];
+
+    zone->scale = scale;
+    zone->delta = hint->cur_pos - FT_MulFix( hint->org_pos, scale );
+    zone->min   = PSH3_ZONE_MIN;
+    zone->max   = hint->org_pos;
+
+    psh3_print_zone( zone );
+
+    zone++;
+
+    for ( count = table->num_hints; count > 0; count-- )
+    {
+      FT_Fixed  scale2;
+
+
+      if ( hint->org_len > 0 )
+      {
+        /* setup a zone for inner-stem interpolation */
+        /* (x' - x0') = (x - x0)*(x1'-x0')/(x1-x0)   */
+        /* x' = x*s2 + x0' - x0*s2                   */
+
+        scale2      = FT_DivFix( hint->cur_len, hint->org_len );
+        zone->scale = scale2;
+        zone->min   = hint->org_pos;
+        zone->max   = hint->org_pos + hint->org_len;
+        zone->delta = hint->cur_pos - FT_MulFix( zone->min, scale2 );
+
+        psh3_print_zone( zone );
+
+        zone++;
+      }
+
+      if ( count == 1 )
+        break;
+
+      sort++;
+      hint2 = sort[0];
+
+      /* setup zone for inter-stem interpolation */
+      /* (x'-x1') = (x-x1)*(x2'-x1')/(x2-x1)     */
+      /* x' = x*s3 + x1' - x1*s3                 */
+
+      scale2 = FT_DivFix( hint2->cur_pos - (hint->cur_pos + hint->cur_len),
+                          hint2->org_pos - (hint->org_pos + hint->org_len) );
+      zone->scale = scale2;
+      zone->min   = hint->org_pos + hint->org_len;
+      zone->max   = hint2->org_pos;
+      zone->delta = hint->cur_pos + hint->cur_len -
+                    FT_MulFix( zone->min, scale2 );
+
+      psh3_print_zone( zone );
+
+      zone++;
+
+      hint = hint2;
+    }
+
+    /* the last zone */
+    zone->scale = scale;
+    zone->min   = hint->org_pos + hint->org_len;
+    zone->max   = PSH3_ZONE_MAX;
+    zone->delta = hint->cur_pos + hint->cur_len -
+                  FT_MulFix( zone->min, scale );
+
+    psh3_print_zone( zone );
+
+    zone++;
+
+    table->num_zones = zone - table->zones;
+    table->zone      = table->zones;
+  }
+#endif
+
+#if 0
+  /* tune a single coordinate with the current interpolation zones */
+  static FT_Pos
+  psh3_hint_table_tune_coord( PSH3_Hint_Table  table,
+                              FT_Int           coord )
+  {
+    PSH3_Zone   zone;
+
+
+    zone = table->zone;
+
+    if ( coord < zone->min )
+    {
+      do
+      {
+        if ( zone == table->zones )
+          break;
+
+        zone--;
+
+      } while ( coord < zone->min );
+      table->zone = zone;
+    }
+    else if ( coord > zone->max )
+    {
+      do
+      {
+        if ( zone == table->zones + table->num_zones - 1 )
+          break;
+
+        zone++;
+
+      } while ( coord > zone->max );
+      table->zone = zone;
+    }
+
+    return FT_MulFix( coord, zone->scale ) + zone->delta;
+  }
+#endif
+
+#if 0
+ /* tune a given outline with current interpolation zones */
+ /* the function only works in a single dimension..       */
+  static void
+  psh3_hint_table_tune_outline( PSH3_Hint_Table  table,
+                                FT_Outline*      outline,
+                                PSH_Globals      globals,
+                                FT_Int           dimension )
+
+  {
+    FT_UInt        count, first, last;
+    PS_Mask_Table  hint_masks = table->hint_masks;
+    PS_Mask        mask;
+    PSH_Dimension  dim        = &globals->dimension[dimension];
+    FT_Fixed       scale      = dim->scale_mult;
+    FT_Fixed       delta      = dim->scale_delta;
+
+
+    if ( hint_masks && hint_masks->num_masks > 0 )
+    {
+      first = 0;
+      mask  = hint_masks->masks;
+      count = hint_masks->num_masks;
+
+      for ( ; count > 0; count--, mask++ )
+      {
+        last = mask->end_point;
+
+        if ( last > first )
+        {
+          FT_Vector*   vec;
+          FT_Int       count2;
+
+
+          psh3_hint_table_activate_mask( table, mask );
+          psh3_hint_table_optimize( table, globals, outline, dimension );
+          psh3_hint_table_setup_zones( table, scale, delta );
+          last = mask->end_point;
+
+          vec    = outline->points + first;
+          count2 = last - first;
+
+          for ( ; count2 > 0; count2--, vec++ )
+          {
+            FT_Pos  x, *px;
+
+
+            px  = dimension ? &vec->y : &vec->x;
+            x   = *px;
+
+            *px = psh3_hint_table_tune_coord( table, (FT_Int)x );
+          }
+        }
+
+        first = last;
+      }
+    }
+    else    /* no hints in this glyph, simply scale the outline */
+    {
+      FT_Vector*  vec;
+
+
+      vec   = outline->points;
+      count = outline->n_points;
+
+      if ( dimension == 0 )
+      {
+        for ( ; count > 0; count--, vec++ )
+          vec->x = FT_MulFix( vec->x, scale ) + delta;
+      }
+      else
+      {
+        for ( ; count > 0; count--, vec++ )
+          vec->y = FT_MulFix( vec->y, scale ) + delta;
+      }
+    }
+  }
+#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 )
+  {
+    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 );
+
+      /* 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 */
--- /dev/null
+++ b/src/pshinter/pshalgo3.h
@@ -1,0 +1,202 @@
+/***************************************************************************/
+/*                                                                         */
+/*  pshalgo3.h                                                             */
+/*                                                                         */
+/*    PostScript hinting algorithm 3 (specification).                      */
+/*                                                                         */
+/*  Copyright 2001 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.                                        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#ifndef __PSHALGO3_H__
+#define __PSHALGO3_H__
+
+
+#include "pshrec.h"
+#include "pshglob.h"
+#include FT_TRIGONOMETRY_H
+
+
+FT_BEGIN_HEADER
+
+
+  typedef struct PSH3_HintRec_*  PSH3_Hint;
+
+  typedef enum
+  {
+    PSH3_HINT_GHOST  = PS_HINT_FLAG_GHOST,
+    PSH3_HINT_BOTTOM = PS_HINT_FLAG_BOTTOM,
+    PSH3_HINT_ACTIVE = 4,
+    PSH3_HINT_FITTED = 8
+
+  } PSH3_Hint_Flags;
+
+
+#define psh3_hint_is_active( x )  ( ( (x)->flags & PSH3_HINT_ACTIVE ) != 0 )
+#define psh3_hint_is_ghost( x )   ( ( (x)->flags & PSH3_HINT_GHOST  ) != 0 )
+#define psh3_hint_is_fitted( x )  ( ( (x)->flags & PSH3_HINT_FITTED ) != 0 )
+
+#define psh3_hint_activate( x )    (x)->flags |=  PSH3_HINT_ACTIVE
+#define psh3_hint_deactivate( x )  (x)->flags &= ~PSH3_HINT_ACTIVE
+#define psh3_hint_set_fitted( x )  (x)->flags |=  PSH3_HINT_FITTED
+
+
+  typedef struct  PSH3_HintRec_
+  {
+    FT_Int     org_pos;
+    FT_Int     org_len;
+    FT_Pos     cur_pos;
+    FT_Pos     cur_len;
+    FT_UInt    flags;
+    PSH3_Hint  parent;
+    FT_Int     order;
+
+  } PSH3_HintRec;
+
+
+  /* this is an interpolation zone used for strong points;  */
+  /* weak points are interpolated according to their strong */
+  /* neighbours                                             */
+  typedef struct  PSH3_ZoneRec_
+  {
+    FT_Fixed  scale;
+    FT_Fixed  delta;
+    FT_Pos    min;
+    FT_Pos    max;
+
+  } PSH3_ZoneRec, *PSH3_Zone;
+
+
+  typedef struct  PSH3_Hint_TableRec_
+  {
+    FT_UInt        max_hints;
+    FT_UInt        num_hints;
+    PSH3_Hint      hints;
+    PSH3_Hint*     sort;
+    PSH3_Hint*     sort_global;
+    FT_UInt        num_zones;
+    PSH3_Zone      zones;
+    PSH3_Zone      zone;
+    PS_Mask_Table  hint_masks;
+    PS_Mask_Table  counter_masks;
+
+  } PSH3_Hint_TableRec, *PSH3_Hint_Table;
+
+
+  typedef struct PSH3_PointRec_*    PSH3_Point;
+  typedef struct PSH3_ContourRec_*  PSH3_Contour;
+
+  enum
+  {
+    PSH3_DIR_NONE  =  4,
+    PSH3_DIR_UP    =  1,
+    PSH3_DIR_DOWN  = -1,
+    PSH3_DIR_LEFT  = -2,
+    PSH3_DIR_RIGHT =  2
+  };
+
+  enum
+  {
+    PSH3_POINT_OFF    = 1,   /* point is off the curve  */
+    PSH3_POINT_STRONG = 2,   /* point is strong         */
+    PSH3_POINT_SMOOTH = 4,   /* point is smooth         */
+    PSH3_POINT_FITTED = 8    /* point is already fitted */
+  };
+
+
+  typedef struct  PSH3_PointRec_
+  {
+    PSH3_Point    prev;
+    PSH3_Point    next;
+    PSH3_Contour  contour;
+    FT_UInt       flags;
+    FT_Char       dir_in;
+    FT_Char       dir_out;
+    FT_Angle      angle_in;
+    FT_Angle      angle_out;
+    PSH3_Hint     hint;
+    FT_Pos        org_u;
+    FT_Pos        cur_u;
+#ifdef DEBUG_HINTER
+    FT_Pos        org_x;
+    FT_Pos        cur_x;
+    FT_Pos        org_y;
+    FT_Pos        cur_y;
+    FT_UInt       flags_x;
+    FT_UInt       flags_y;
+#endif
+
+  } PSH3_PointRec;
+
+
+#define psh3_point_is_strong( p )   ( (p)->flags & PSH3_POINT_STRONG )
+#define psh3_point_is_fitted( p )   ( (p)->flags & PSH3_POINT_FITTED )
+#define psh3_point_is_smooth( p )   ( (p)->flags & PSH3_POINT_SMOOTH )
+
+#define psh3_point_set_strong( p )  (p)->flags |= PSH3_POINT_STRONG
+#define psh3_point_set_fitted( p )  (p)->flags |= PSH3_POINT_FITTED
+#define psh3_point_set_smooth( p )  (p)->flags |= PSH3_POINT_SMOOTH
+
+
+  typedef struct  PSH3_ContourRec_
+  {
+    PSH3_Point  start;
+    FT_UInt     count;
+
+  } PSH3_ContourRec;
+
+
+  typedef struct  PSH3_GlyphRec_
+  {
+    FT_UInt             num_points;
+    FT_UInt             num_contours;
+
+    PSH3_Point          points;
+    PSH3_Contour        contours;
+
+    FT_Memory           memory;
+    FT_Outline*         outline;
+    PSH_Globals         globals;
+    PSH3_Hint_TableRec  hint_tables[2];
+
+    FT_Bool             vertical;
+    FT_Int              major_dir;
+    FT_Int              minor_dir;
+
+  } PSH3_GlyphRec, *PSH3_Glyph;
+
+
+#ifdef DEBUG_HINTER
+  extern PSH3_Hint_Table  ps3_debug_hint_table;
+
+  typedef void
+  (*PSH3_HintFunc)( PSH3_Hint  hint,
+                    FT_Bool    vertical );
+
+  extern PSH3_HintFunc    ps3_debug_hint_func;
+
+  extern PSH3_Glyph       ps3_debug_glyph;
+#endif
+
+
+  extern FT_Error
+  ps3_hints_apply( PS_Hints     ps_hints,
+                   FT_Outline*  outline,
+                   PSH_Globals  globals );
+
+
+FT_END_HEADER
+
+
+#endif /* __PSHALGO3_H__ */
+
+
+/* END */
--- a/src/pshinter/pshinter.c
+++ b/src/pshinter/pshinter.c
@@ -23,6 +23,7 @@
 #include "pshglob.c"
 #include "pshalgo1.c"
 #include "pshalgo2.c"
+#include "pshalgo3.c"
 #include "pshmod.c"
 
 
--- a/src/pshinter/rules.mk
+++ b/src/pshinter/rules.mk
@@ -30,7 +30,8 @@
                     $(PSHINTER_DIR_)pshglob.c  \
                     $(PSHINTER_DIR_)pshmod.c   \
                     $(PSHINTER_DIR_)pshalgo1.c \
-                    $(PSHINTER_DIR_)pshalgo2.c
+                    $(PSHINTER_DIR_)pshalgo2.c \
+                    $(PSHINTER_DIR_)pshalgo3.c
 
 
 # PSHINTER driver headers
--- a/tests/gview.c
+++ b/tests/gview.c
@@ -130,7 +130,9 @@
   nv_path_new_rectangle( renderer, -1, -1, 3, 3, 0, 0, &symbol_square );
   nv_path_new_rectangle( renderer, -1, -6, 2, 12, 0, 0, &symbol_rect_v );
   nv_path_new_rectangle( renderer, -6, -1, 12, 2, 0, 0, &symbol_rect_h );
+
   nv_path_new_circle( renderer, 0, 0, 3., &symbol_dot );
+
   nv_path_stroke( symbol_dot, 0.6,
                   nv_path_linecap_butt,
                   nv_path_linejoin_miter, 1.,
@@ -137,8 +139,8 @@
                   &symbol_circle );
 
   nv_path_destroy( symbol_dot );
-  nv_path_new_circle( renderer, 0, 0, 2., &symbol_dot );
 
+  nv_path_new_circle( renderer, 0, 0, 2., &symbol_dot );
  }
 
 static void