kc3-lang/freetype/src/pshinter/pshalgo1.c

Branch : - branch - master v2.13 - tag -

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  Commit

• Author : David Turner
  Date : 2001-12-05 15:59:33
  Hash : 14183ea0
  Message : First of all, a big thanks to Werner and Antoine for their latest work !! * src/pshinter/pshalgo2.c (psh2_hint_table_init), src/pshinter/pshalgo1.c (psh1_hint_table_init): removed compiler warnings * include/freetype/cache/*, src/cache/*: yet another massive rewrite of the caching sub-system, in order to both increase performance and allow simpler cache sub-classing. As an example, the code for the image and sbit caches is now much simpler I still need to update the documentation in www/freetype2/docs/cache.html to reflect the new design though..

• src/pshinter/pshalgo1.c

• /***************************************************************************/
  /*                                                                         */
  /*  pshalgo1.c                                                             */
  /*                                                                         */
  /*    PostScript hinting algorithm 1 (body).                               */
  /*                                                                         */
  /*  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.                                        */
  /*                                                                         */
  /***************************************************************************/
  
  
  #include <ft2build.h>
  #include FT_INTERNAL_OBJECTS_H
  #include FT_INTERNAL_DEBUG_H
  #include "pshalgo1.h"
  
  
  #ifdef DEBUG_HINTER
    extern PSH1_Hint_Table  ps1_debug_hint_table = 0;
    extern PSH1_HintFunc    ps1_debug_hint_func  = 0;
  #endif
  
  
   /************************************************************************/
   /************************************************************************/
   /*****                                                              *****/
   /*****                 BASIC HINTS RECORDINGS                       *****/
   /*****                                                              *****/
   /************************************************************************/
   /************************************************************************/
  
    /* return true iff two stem hints overlap */
    static FT_Int
    psh1_hint_overlap( PSH1_Hint  hint1,
                       PSH1_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
    psh1_hint_table_done( PSH1_Hint_Table  table,
                          FT_Memory        memory )
    {
      FREE( table->zones );
      table->num_zones = 0;
      table->zone      = 0;
  
      FREE( table->sort );
      FREE( table->hints );
      table->num_hints   = 0;
      table->max_hints   = 0;
      table->sort_global = 0;
    }
  
  
    /* deactivate all hints in a table */
    static void
    psh1_hint_table_deactivate( PSH1_Hint_Table  table )
    {
      FT_UInt    count = table->max_hints;
      PSH1_Hint  hint  = table->hints;
  
  
      for ( ; count > 0; count--, hint++ )
      {
        psh1_hint_deactivate( hint );
        hint->order = -1;
      }
    }
  
  
    /* internal function used to record a new hint */
    static void
    psh1_hint_table_record( PSH1_Hint_Table  table,
                            FT_UInt          index )
    {
      PSH1_Hint  hint = table->hints + index;
  
  
      if ( index >= table->max_hints )
      {
        FT_ERROR(( "%s.activate: invalid hint index %d\n", index ));
        return;
      }
  
      /* ignore active hints */
      if ( psh1_hint_is_active( hint ) )
        return;
  
      psh1_hint_activate( hint );
  
      /* now scan the current active hint set in order to determine */
      /* if we are overlapping with another segment                 */
      {
        PSH1_Hint*  sorted = table->sort_global;
        FT_UInt     count  = table->num_hints;
        PSH1_Hint   hint2;
  
  
        hint->parent = 0;
        for ( ; count > 0; count--, sorted++ )
        {
          hint2 = sorted[0];
  
          if ( psh1_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
    psh1_hint_table_record_mask( PSH1_Hint_Table  table,
                                 PS_Mask          hint_mask )
    {
      FT_Int    mask = 0, val = 0;
      FT_Byte*  cursor = hint_mask->bytes;
      FT_UInt   index, limit;
  
  
      limit = hint_mask->num_bits;
  
      if ( limit != table->max_hints )
        FT_ERROR(( "%s.activate_mask: invalid bit count (%d instead of %d)\n",
                   "ps.fitter", hint_mask->num_bits, table->max_hints ));
  
      for ( index = 0; index < limit; index++ )
      {
        if ( mask == 0 )
        {
          val  = *cursor++;
          mask = 0x80;
        }
  
        if ( val & mask )
          psh1_hint_table_record( table, index );
  
        mask >>= 1;
      }
    }
  
  
    /* create hints table */
    static FT_Error
    psh1_hint_table_init( PSH1_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 ( ALLOC_ARRAY( table->sort,  2 * count,     PSH1_Hint    ) ||
           ALLOC_ARRAY( table->hints,     count,     PSH1_HintRec ) ||
           ALLOC_ARRAY( table->zones, 2 * count + 1, PSH1_ZoneRec ) )
        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 */
      {
        PSH1_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++ )
          psh1_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++ )
          psh1_hint_table_record( table, Index );
      }
  
    Exit:
      return error;
    }
  
  
    static void
    psh1_hint_table_activate_mask( PSH1_Hint_Table  table,
                                   PS_Mask          hint_mask )
    {
      FT_Int    mask = 0, val = 0;
      FT_Byte*  cursor = hint_mask->bytes;
      FT_UInt   index, limit, count;
  
  
      limit = hint_mask->num_bits;
      count = 0;
  
      psh1_hint_table_deactivate( table );
  
      for ( index = 0; index < limit; index++ )
      {
        if ( mask == 0 )
        {
          val  = *cursor++;
          mask = 0x80;
        }
  
        if ( val & mask )
        {
          PSH1_Hint  hint = &table->hints[index];
  
  
          if ( !psh1_hint_is_active( hint ) )
          {
            PSH1_Hint*  sort = table->sort;
            FT_UInt     count2;
            PSH1_Hint   hint2;
  
  
            for ( count2 = count; count2 > 0; count2--, sort++ )
            {
              hint2 = sort[0];
              if ( psh1_hint_overlap( hint, hint2 ) )
              {
                FT_ERROR(( "%s.activate_mask: found overlapping hints\n",
                           "psf.hint" ));
                break;
              }
            }
  
            if ( count2 == 0 )
            {
              psh1_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;
        PSH1_Hint   hint1, hint2;
        PSH1_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
    void
    ps_simple_scale( PSH1_Hint_Table  table,
                     FT_Fixed         scale,
                     FT_Fixed         delta,
                     FT_Int           vertical )
    {
      PSH1_Hint  hint;
      FT_UInt    count;
  
  
      for ( count = 0; count < table->num_hints; count++ )
      {
        hint = table->sort[count];
        if ( psh1_hint_is_active( hint ) )
        {
          hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta;
          hint->cur_len = FT_MulFix( hint->org_len, scale );
  
          if ( ps1_debug_hint_func )
            ps1_debug_hint_func( hint, vertical );
        }
      }
    }
  #endif
  
  
    FT_LOCAL_DEF  FT_Error
    psh1_hint_table_optimize( PSH1_Hint_Table  table,
                              PSH_Globals      globals,
                              FT_Outline*      outline,
                              FT_Int           vertical )
    {
      PSH_Dimension  dim   = &globals->dimension[vertical];
      FT_Fixed       scale = dim->scale_mult;
      FT_Fixed       delta = dim->scale_delta;
  
      FT_UNUSED( outline );
  
  
  #ifdef DEBUG_HINTER
      if ( ps_debug_no_vert_hints && vertical )
      {
        ps_simple_scale( table, scale, delta, vertical );
        return 0;
      }
  
      if ( ps_debug_no_horz_hints && !vertical )
      {
        ps_simple_scale( table, scale, delta, vertical );
        return 0;
      }
  #endif
  
      /* XXXX: for now, we only scale the hints to test all other aspects */
      /*       of the PostScript hinter                                   */
      {
        PSH1_Hint  hint;
        FT_UInt   count;
  
  
        for ( count = 0; count < table->num_hints; count++ )
        {
          hint = table->sort[count];
          if ( psh1_hint_is_active( hint ) )
          {
  #if 1
            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;
  
  
            /* compute fitted width/height */
            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     = 0;
            align.align_bot = align.align_top = 0;
            if ( !vertical )
            {
              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:
              /* 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
  
            hint->cur_pos = ( FT_MulFix( hint->org_pos, scale ) + delta + 32 )
                            & -64;
            hint->cur_len = FT_MulFix( hint->org_len, scale );
  
  # endif
  
  #ifdef DEBUG_HINTER
          if ( ps1_debug_hint_func )
            ps1_debug_hint_func( hint, vertical );
  #endif
          }
        }
      }
  
      return 0;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****               POINTS INTERPOLATION ROUTINES                   *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  #define PSH1_ZONE_MIN  -3200000
  #define PSH1_ZONE_MAX  +3200000
  
  #define xxDEBUG_ZONES
  
  
  #ifdef DEBUG_ZONES
  
  #include <stdio.h>
  
    static void
    print_zone( PSH1_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 print_zone( x )  do { } while ( 0 )
  #endif
  
    /* setup interpolation zones once the hints have been grid-fitted */
    /* by the optimizer                                               */
    static void
    psh1_hint_table_setup_zones( PSH1_Hint_Table  table,
                                 FT_Fixed         scale,
                                 FT_Fixed         delta )
    {
      FT_UInt     count;
      PSH1_Zone   zone;
      PSH1_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   = PSH1_ZONE_MIN;
        zone->max   = PSH1_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   = PSH1_ZONE_MIN;
      zone->max   = hint->org_pos;
  
      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 );
  
          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 );
  
        print_zone( zone );
  
        zone++;
  
        hint = hint2;
      }
  
      /* the last zone */
      zone->scale = scale;
      zone->min   = hint->org_pos + hint->org_len;
      zone->max   = PSH1_ZONE_MAX;
      zone->delta = hint->cur_pos + hint->cur_len -
                    FT_MulFix( zone->min, scale );
  
      print_zone( zone );
  
      zone++;
  
      table->num_zones = zone - table->zones;
      table->zone      = table->zones;
    }
  
  
    /* tune a single coordinate with the current interpolation zones */
    static FT_Pos
    psh1_hint_table_tune_coord( PSH1_Hint_Table  table,
                                FT_Int           coord )
    {
      PSH1_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;
    }
  
  
    /* tune a given outline with current interpolation zones. */
    /* The function only works in a single dimension.         */
    static void
    psh1_hint_table_tune_outline( PSH1_Hint_Table  table,
                                  FT_Outline*      outline,
                                  PSH_Globals      globals,
                                  FT_Int           vertical )
  
    {
      FT_UInt         count, first, last;
      PS_Mask_Table   hint_masks = table->hint_masks;
      PS_Mask         mask;
      PSH_Dimension   dim        = &globals->dimension[vertical];
      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;
  
  
            psh1_hint_table_activate_mask( table, mask );
            psh1_hint_table_optimize( table, globals, outline, vertical );
            psh1_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  = vertical ? &vec->x : &vec->y;
              x   = *px;
  
              *px = psh1_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 ( vertical )
        {
          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;
        }
      }
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                     HIGH-LEVEL INTERFACE                      *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    FT_Error
    ps1_hints_apply( PS_Hints     ps_hints,
                     FT_Outline*  outline,
                     PSH_Globals  globals )
    {
      PSH1_Hint_TableRec  hints;
      FT_Error            error = 0;
      FT_Int              dimension;
  
  
      for ( dimension = 1; dimension >= 0; dimension-- )
      {
        PS_Dimension  dim = &ps_hints->dimension[dimension];
  
  
        /* initialize hints table */
        memset( &hints, 0, sizeof ( hints ) );
        error = psh1_hint_table_init( &hints,
                                      &dim->hints,
                                      &dim->masks,
                                      &dim->counters,
                                      ps_hints->memory );
        if ( error )
          goto Exit;
  
        psh1_hint_table_tune_outline( &hints,
                                      outline,
                                      globals,
                                      dimension );
  
        psh1_hint_table_done( &hints, ps_hints->memory );
      }
  
    Exit:
      return error;
    }
  
  
  /* END */