text: /****************************************************************************
   *
   * pshrec.c
   *
   *   FreeType PostScript hints recorder (body).
   *
   * Copyright (C) 2001-2020 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_FREETYPE_H
  #include FT_INTERNAL_OBJECTS_H
  #include FT_INTERNAL_DEBUG_H
  #include FT_INTERNAL_CALC_H
  
  #include "pshrec.h"
  #include "pshalgo.h"
  
  #include "pshnterr.h"
  
  #undef  FT_COMPONENT
  #define FT_COMPONENT  pshrec
  
  #ifdef DEBUG_HINTER
    PS_Hints  ps_debug_hints         = NULL;
    int       ps_debug_no_horz_hints = 0;
    int       ps_debug_no_vert_hints = 0;
  #endif
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                      PS_HINT MANAGEMENT                       *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    /* destroy hints table */
    static void
    ps_hint_table_done( PS_Hint_Table  table,
                        FT_Memory      memory )
    {
      FT_FREE( table->hints );
      table->num_hints = 0;
      table->max_hints = 0;
    }
  
  
    /* ensure that a table can contain "count" elements */
    static FT_Error
    ps_hint_table_ensure( PS_Hint_Table  table,
                          FT_UInt        count,
                          FT_Memory      memory )
    {
      FT_UInt   old_max = table->max_hints;
      FT_UInt   new_max = count;
      FT_Error  error   = FT_Err_Ok;
  
  
      if ( new_max > old_max )
      {
        /* try to grow the table */
        new_max = FT_PAD_CEIL( new_max, 8 );
        if ( !FT_RENEW_ARRAY( table->hints, old_max, new_max ) )
          table->max_hints = new_max;
      }
      return error;
    }
  
  
    static FT_Error
    ps_hint_table_alloc( PS_Hint_Table  table,
                         FT_Memory      memory,
                         PS_Hint       *ahint )
    {
      FT_Error  error = FT_Err_Ok;
      FT_UInt   count;
      PS_Hint   hint = NULL;
  
  
      count = table->num_hints;
      count++;
  
      if ( count >= table->max_hints )
      {
        error = ps_hint_table_ensure( table, count, memory );
        if ( error )
          goto Exit;
      }
  
      hint        = table->hints + count - 1;
      hint->pos   = 0;
      hint->len   = 0;
      hint->flags = 0;
  
      table->num_hints = count;
  
    Exit:
      *ahint = hint;
      return error;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                      PS_MASK MANAGEMENT                       *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    /* destroy mask */
    static void
    ps_mask_done( PS_Mask    mask,
                  FT_Memory  memory )
    {
      FT_FREE( mask->bytes );
      mask->num_bits  = 0;
      mask->max_bits  = 0;
      mask->end_point = 0;
    }
  
  
    /* ensure that a mask can contain "count" bits */
    static FT_Error
    ps_mask_ensure( PS_Mask    mask,
                    FT_UInt    count,
                    FT_Memory  memory )
    {
      FT_UInt   old_max = ( mask->max_bits + 7 ) >> 3;
      FT_UInt   new_max = ( count          + 7 ) >> 3;
      FT_Error  error   = FT_Err_Ok;
  
  
      if ( new_max > old_max )
      {
        new_max = FT_PAD_CEIL( new_max, 8 );
        if ( !FT_RENEW_ARRAY( mask->bytes, old_max, new_max ) )
          mask->max_bits = new_max * 8;
      }
      return error;
    }
  
  
    /* test a bit value in a given mask */
    static FT_Int
    ps_mask_test_bit( PS_Mask  mask,
                      FT_Int   idx )
    {
      if ( (FT_UInt)idx >= mask->num_bits )
        return 0;
  
      return mask->bytes[idx >> 3] & ( 0x80 >> ( idx & 7 ) );
    }
  
  
    /* clear a given bit */
    static void
    ps_mask_clear_bit( PS_Mask  mask,
                       FT_UInt  idx )
    {
      FT_Byte*  p;
  
  
      if ( idx >= mask->num_bits )
        return;
  
      p    = mask->bytes + ( idx >> 3 );
      p[0] = (FT_Byte)( p[0] & ~( 0x80 >> ( idx & 7 ) ) );
    }
  
  
    /* set a given bit, possibly grow the mask */
    static FT_Error
    ps_mask_set_bit( PS_Mask    mask,
                     FT_UInt    idx,
                     FT_Memory  memory )
    {
      FT_Error  error = FT_Err_Ok;
      FT_Byte*  p;
  
  
      if ( idx >= mask->num_bits )
      {
        error = ps_mask_ensure( mask, idx + 1, memory );
        if ( error )
          goto Exit;
  
        mask->num_bits = idx + 1;
      }
  
      p    = mask->bytes + ( idx >> 3 );
      p[0] = (FT_Byte)( p[0] | ( 0x80 >> ( idx & 7 ) ) );
  
    Exit:
      return error;
    }
  
  
    /* destroy mask table */
    static void
    ps_mask_table_done( PS_Mask_Table  table,
                        FT_Memory      memory )
    {
      FT_UInt  count = table->max_masks;
      PS_Mask  mask  = table->masks;
  
  
      for ( ; count > 0; count--, mask++ )
        ps_mask_done( mask, memory );
  
      FT_FREE( table->masks );
      table->num_masks = 0;
      table->max_masks = 0;
    }
  
  
    /* ensure that a mask table can contain "count" masks */
    static FT_Error
    ps_mask_table_ensure( PS_Mask_Table  table,
                          FT_UInt        count,
                          FT_Memory      memory )
    {
      FT_UInt   old_max = table->max_masks;
      FT_UInt   new_max = count;
      FT_Error  error   = FT_Err_Ok;
  
  
      if ( new_max > old_max )
      {
        new_max = FT_PAD_CEIL( new_max, 8 );
        if ( !FT_RENEW_ARRAY( table->masks, old_max, new_max ) )
          table->max_masks = new_max;
      }
      return error;
    }
  
  
    /* allocate a new mask in a table */
    static FT_Error
    ps_mask_table_alloc( PS_Mask_Table  table,
                         FT_Memory      memory,
                         PS_Mask       *amask )
    {
      FT_UInt   count;
      FT_Error  error = FT_Err_Ok;
      PS_Mask   mask  = NULL;
  
  
      count = table->num_masks;
      count++;
  
      if ( count > table->max_masks )
      {
        error = ps_mask_table_ensure( table, count, memory );
        if ( error )
          goto Exit;
      }
  
      mask             = table->masks + count - 1;
      mask->num_bits   = 0;
      mask->end_point  = 0;
      table->num_masks = count;
  
    Exit:
      *amask = mask;
      return error;
    }
  
  
    /* return last hint mask in a table, create one if the table is empty */
    static FT_Error
    ps_mask_table_last( PS_Mask_Table  table,
                        FT_Memory      memory,
                        PS_Mask       *amask )
    {
      FT_Error  error = FT_Err_Ok;
      FT_UInt   count;
      PS_Mask   mask;
  
  
      count = table->num_masks;
      if ( count == 0 )
      {
        error = ps_mask_table_alloc( table, memory, &mask );
        if ( error )
          goto Exit;
      }
      else
        mask = table->masks + count - 1;
  
    Exit:
      *amask = mask;
      return error;
    }
  
  
    /* set a new mask to a given bit range */
    static FT_Error
    ps_mask_table_set_bits( PS_Mask_Table   table,
                            const FT_Byte*  source,
                            FT_UInt         bit_pos,
                            FT_UInt         bit_count,
                            FT_Memory       memory )
    {
      FT_Error  error;
      PS_Mask   mask;
  
  
      error = ps_mask_table_last( table, memory, &mask );
      if ( error )
        goto Exit;
  
      error = ps_mask_ensure( mask, bit_count, memory );
      if ( error )
        goto Exit;
  
      mask->num_bits = bit_count;
  
      /* now, copy bits */
      {
        FT_Byte*  read  = (FT_Byte*)source + ( bit_pos >> 3 );
        FT_Int    rmask = 0x80 >> ( bit_pos & 7 );
        FT_Byte*  write = mask->bytes;
        FT_Int    wmask = 0x80;
        FT_Int    val;
  
  
        for ( ; bit_count > 0; bit_count-- )
        {
          val = write[0] & ~wmask;
  
          if ( read[0] & rmask )
            val |= wmask;
  
          write[0] = (FT_Byte)val;
  
          rmask >>= 1;
          if ( rmask == 0 )
          {
            read++;
            rmask = 0x80;
          }
  
          wmask >>= 1;
          if ( wmask == 0 )
          {
            write++;
            wmask = 0x80;
          }
        }
      }
  
    Exit:
      return error;
    }
  
  
    /* test whether two masks in a table intersect */
    static FT_Int
    ps_mask_table_test_intersect( PS_Mask_Table  table,
                                  FT_UInt        index1,
                                  FT_UInt        index2 )
    {
      PS_Mask   mask1  = table->masks + index1;
      PS_Mask   mask2  = table->masks + index2;
      FT_Byte*  p1     = mask1->bytes;
      FT_Byte*  p2     = mask2->bytes;
      FT_UInt   count1 = mask1->num_bits;
      FT_UInt   count2 = mask2->num_bits;
      FT_UInt   count;
  
  
      count = FT_MIN( count1, count2 );
      for ( ; count >= 8; count -= 8 )
      {
        if ( p1[0] & p2[0] )
          return 1;
  
        p1++;
        p2++;
      }
  
      if ( count == 0 )
        return 0;
  
      return ( p1[0] & p2[0] ) & ~( 0xFF >> count );
    }
  
  
    /* merge two masks, used by ps_mask_table_merge_all */
    static FT_Error
    ps_mask_table_merge( PS_Mask_Table  table,
                         FT_UInt        index1,
                         FT_UInt        index2,
                         FT_Memory      memory )
    {
      FT_Error  error = FT_Err_Ok;
  
  
      /* swap index1 and index2 so that index1 < index2 */
      if ( index1 > index2 )
      {
        FT_UInt  temp;
  
  
        temp   = index1;
        index1 = index2;
        index2 = temp;
      }
  
      if ( index1 < index2 && index2 < table->num_masks )
      {
        /* we need to merge the bitsets of index1 and index2 with a */
        /* simple union                                             */
        PS_Mask  mask1  = table->masks + index1;
        PS_Mask  mask2  = table->masks + index2;
        FT_UInt  count1 = mask1->num_bits;
        FT_UInt  count2 = mask2->num_bits;
        FT_Int   delta;
  
  
        if ( count2 > 0 )
        {
          FT_UInt   pos;
          FT_Byte*  read;
          FT_Byte*  write;
  
  
          /* if "count2" is greater than "count1", we need to grow the */
          /* first bitset, and clear the highest bits                  */
          if ( count2 > count1 )
          {
            error = ps_mask_ensure( mask1, count2, memory );
            if ( error )
              goto Exit;
  
            for ( pos = count1; pos < count2; pos++ )
              ps_mask_clear_bit( mask1, pos );
          }
  
          /* merge (unite) the bitsets */
          read  = mask2->bytes;
          write = mask1->bytes;
          pos   = ( count2 + 7 ) >> 3;
  
          for ( ; pos > 0; pos-- )
          {
            write[0] = (FT_Byte)( write[0] | read[0] );
            write++;
            read++;
          }
        }
  
        /* Now, remove "mask2" from the list.  We need to keep the masks */
        /* sorted in order of importance, so move table elements.        */
        mask2->num_bits  = 0;
        mask2->end_point = 0;
  
        /* number of masks to move */
        delta = (FT_Int)( table->num_masks - 1 - index2 );
        if ( delta > 0 )
        {
          /* move to end of table for reuse */
          PS_MaskRec  dummy = *mask2;
  
  
          ft_memmove( mask2,
                      mask2 + 1,
                      (FT_UInt)delta * sizeof ( PS_MaskRec ) );
  
          mask2[delta] = dummy;
        }
  
        table->num_masks--;
      }
      else
        FT_TRACE0(( "ps_mask_table_merge: ignoring invalid indices (%d,%d)\n",
                    index1, index2 ));
  
    Exit:
      return error;
    }
  
  
    /* Try to merge all masks in a given table.  This is used to merge */
    /* all counter masks into independent counter "paths".             */
    /*                                                                 */
    static FT_Error
    ps_mask_table_merge_all( PS_Mask_Table  table,
                             FT_Memory      memory )
    {
      FT_Int    index1, index2;
      FT_Error  error = FT_Err_Ok;
  
  
      /* both loops go down to 0, thus FT_Int for index1 and index2 */
      for ( index1 = (FT_Int)table->num_masks - 1; index1 > 0; index1-- )
      {
        for ( index2 = index1 - 1; index2 >= 0; index2-- )
        {
          if ( ps_mask_table_test_intersect( table,
                                             (FT_UInt)index1,
                                             (FT_UInt)index2 ) )
          {
            error = ps_mask_table_merge( table,
                                         (FT_UInt)index2,
                                         (FT_UInt)index1,
                                         memory );
            if ( error )
              goto Exit;
  
            break;
          }
        }
      }
  
    Exit:
      return error;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                    PS_DIMENSION MANAGEMENT                    *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  
    /* finalize a given dimension */
    static void
    ps_dimension_done( PS_Dimension  dimension,
                       FT_Memory     memory )
    {
      ps_mask_table_done( &dimension->counters, memory );
      ps_mask_table_done( &dimension->masks,    memory );
      ps_hint_table_done( &dimension->hints,    memory );
    }
  
  
    /* initialize a given dimension */
    static void
    ps_dimension_init( PS_Dimension  dimension )
    {
      dimension->hints.num_hints    = 0;
      dimension->masks.num_masks    = 0;
      dimension->counters.num_masks = 0;
    }
  
  
  #if 0
  
    /* set a bit at a given index in the current hint mask */
    static FT_Error
    ps_dimension_set_mask_bit( PS_Dimension  dim,
                               FT_UInt       idx,
                               FT_Memory     memory )
    {
      PS_Mask   mask;
      FT_Error  error = FT_Err_Ok;
  
  
      /* get last hint mask */
      error = ps_mask_table_last( &dim->masks, memory, &mask );
      if ( error )
        goto Exit;
  
      error = ps_mask_set_bit( mask, idx, memory );
  
    Exit:
      return error;
    }
  
  #endif
  
    /* set the end point in a mask, called from "End" & "Reset" methods */
    static void
    ps_dimension_end_mask( PS_Dimension  dim,
                           FT_UInt       end_point )
    {
      FT_UInt  count = dim->masks.num_masks;
  
  
      if ( count > 0 )
      {
        PS_Mask  mask = dim->masks.masks + count - 1;
  
  
        mask->end_point = end_point;
      }
    }
  
  
    /* set the end point in the current mask, then create a new empty one */
    /* (called by "Reset" method)                                         */
    static FT_Error
    ps_dimension_reset_mask( PS_Dimension  dim,
                             FT_UInt       end_point,
                             FT_Memory     memory )
    {
      PS_Mask  mask;
  
  
      /* end current mask */
      ps_dimension_end_mask( dim, end_point );
  
      /* allocate new one */
      return ps_mask_table_alloc( &dim->masks, memory, &mask );
    }
  
  
    /* set a new mask, called from the "T2Stem" method */
    static FT_Error
    ps_dimension_set_mask_bits( PS_Dimension    dim,
                                const FT_Byte*  source,
                                FT_UInt         source_pos,
                                FT_UInt         source_bits,
                                FT_UInt         end_point,
                                FT_Memory       memory )
    {
      FT_Error  error;
  
  
      /* reset current mask, if any */
      error = ps_dimension_reset_mask( dim, end_point, memory );
      if ( error )
        goto Exit;
  
      /* set bits in new mask */
      error = ps_mask_table_set_bits( &dim->masks, source,
                                      source_pos, source_bits, memory );
  
    Exit:
      return error;
    }
  
  
    /* add a new single stem (called from "T1Stem" method) */
    static FT_Error
    ps_dimension_add_t1stem( PS_Dimension  dim,
                             FT_Int        pos,
                             FT_Int        len,
                             FT_Memory     memory,
                             FT_Int       *aindex )
    {
      FT_Error  error = FT_Err_Ok;
      FT_UInt   flags = 0;
  
  
      /* detect ghost stem */
      if ( len < 0 )
      {
        flags |= PS_HINT_FLAG_GHOST;
        if ( len == -21 )
        {
          flags |= PS_HINT_FLAG_BOTTOM;
          pos    = ADD_INT( pos, len );
        }
        len = 0;
      }
  
      if ( aindex )
        *aindex = -1;
  
      /* now, lookup stem in the current hints table */
      {
        PS_Mask  mask;
        FT_UInt  idx;
        FT_UInt  max  = dim->hints.num_hints;
        PS_Hint  hint = dim->hints.hints;
  
  
        for ( idx = 0; idx < max; idx++, hint++ )
        {
          if ( hint->pos == pos && hint->len == len )
            break;
        }
  
        /* we need to create a new hint in the table */
        if ( idx >= max )
        {
          error = ps_hint_table_alloc( &dim->hints, memory, &hint );
          if ( error )
            goto Exit;
  
          hint->pos   = pos;
          hint->len   = len;
          hint->flags = flags;
        }
  
        /* now, store the hint in the current mask */
        error = ps_mask_table_last( &dim->masks, memory, &mask );
        if ( error )
          goto Exit;
  
        error = ps_mask_set_bit( mask, idx, memory );
        if ( error )
          goto Exit;
  
        if ( aindex )
          *aindex = (FT_Int)idx;
      }
  
    Exit:
      return error;
    }
  
  
    /* add a "hstem3/vstem3" counter to our dimension table */
    static FT_Error
    ps_dimension_add_counter( PS_Dimension  dim,
                              FT_Int        hint1,
                              FT_Int        hint2,
                              FT_Int        hint3,
                              FT_Memory     memory )
    {
      FT_Error  error   = FT_Err_Ok;
      FT_UInt   count   = dim->counters.num_masks;
      PS_Mask   counter = dim->counters.masks;
  
  
      /* try to find an existing counter mask that already uses */
      /* one of these stems here                                */
      for ( ; count > 0; count--, counter++ )
      {
        if ( ps_mask_test_bit( counter, hint1 ) ||
             ps_mask_test_bit( counter, hint2 ) ||
             ps_mask_test_bit( counter, hint3 ) )
          break;
      }
  
      /* create a new counter when needed */
      if ( count == 0 )
      {
        error = ps_mask_table_alloc( &dim->counters, memory, &counter );
        if ( error )
          goto Exit;
      }
  
      /* now, set the bits for our hints in the counter mask */
      if ( hint1 >= 0 )
      {
        error = ps_mask_set_bit( counter, (FT_UInt)hint1, memory );
        if ( error )
          goto Exit;
      }
  
      if ( hint2 >= 0 )
      {
        error = ps_mask_set_bit( counter, (FT_UInt)hint2, memory );
        if ( error )
          goto Exit;
      }
  
      if ( hint3 >= 0 )
      {
        error = ps_mask_set_bit( counter, (FT_UInt)hint3, memory );
        if ( error )
          goto Exit;
      }
  
    Exit:
      return error;
    }
  
  
    /* end of recording session for a given dimension */
    static FT_Error
    ps_dimension_end( PS_Dimension  dim,
                      FT_UInt       end_point,
                      FT_Memory     memory )
    {
      /* end hint mask table */
      ps_dimension_end_mask( dim, end_point );
  
      /* merge all counter masks into independent "paths" */
      return ps_mask_table_merge_all( &dim->counters, memory );
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                    PS_RECORDER MANAGEMENT                     *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  
    /* destroy hints */
    FT_LOCAL( void )
    ps_hints_done( PS_Hints  hints )
    {
      FT_Memory  memory = hints->memory;
  
  
      ps_dimension_done( &hints->dimension[0], memory );
      ps_dimension_done( &hints->dimension[1], memory );
  
      hints->error  = FT_Err_Ok;
      hints->memory = NULL;
    }
  
  
    FT_LOCAL( void )
    ps_hints_init( PS_Hints   hints,
                   FT_Memory  memory )
    {
      FT_ZERO( hints );
      hints->memory = memory;
    }
  
  
    /* initialize a hints for a new session */
    static void
    ps_hints_open( PS_Hints      hints,
                   PS_Hint_Type  hint_type )
    {
      hints->error     = FT_Err_Ok;
      hints->hint_type = hint_type;
  
      ps_dimension_init( &hints->dimension[0] );
      ps_dimension_init( &hints->dimension[1] );
    }
  
  
    /* add one or more stems to the current hints table */
    static void
    ps_hints_stem( PS_Hints  hints,
                   FT_UInt   dimension,
                   FT_Int    count,
                   FT_Long*  stems )
    {
      PS_Dimension  dim;
  
  
      if ( hints->error )
        return;
  
      /* limit "dimension" to 0..1 */
      if ( dimension > 1 )
      {
        FT_TRACE0(( "ps_hints_stem: invalid dimension (%d) used\n",
                    dimension ));
        dimension = ( dimension != 0 );
      }
  
      /* record the stems in the current hints/masks table */
      /* (Type 1 & 2's `hstem' or `vstem' operators)       */
      dim = &hints->dimension[dimension];
  
      for ( ; count > 0; count--, stems += 2 )
      {
        FT_Error   error;
        FT_Memory  memory = hints->memory;
  
  
        error = ps_dimension_add_t1stem( dim,
                                         (FT_Int)stems[0],
                                         (FT_Int)stems[1],
                                         memory,
                                         NULL );
        if ( error )
        {
          FT_ERROR(( "ps_hints_stem: could not add stem"
                     " (%d,%d) to hints table\n", stems[0], stems[1] ));
  
          hints->error = error;
          return;
        }
      }
    }
  
  
    /* add one Type1 counter stem to the current hints table */
    static void
    ps_hints_t1stem3( PS_Hints   hints,
                      FT_UInt    dimension,
                      FT_Fixed*  stems )
    {
      FT_Error  error = FT_Err_Ok;
  
  
      if ( !hints->error )
      {
        PS_Dimension  dim;
        FT_Memory     memory = hints->memory;
        FT_Int        count;
        FT_Int        idx[3];
  
  
        /* limit "dimension" to 0..1 */
        if ( dimension > 1 )
        {
          FT_TRACE0(( "ps_hints_t1stem3: invalid dimension (%d) used\n",
                      dimension ));
          dimension = ( dimension != 0 );
        }
  
        dim = &hints->dimension[dimension];
  
        /* there must be 6 elements in the 'stem' array */
        if ( hints->hint_type == PS_HINT_TYPE_1 )
        {
          /* add the three stems to our hints/masks table */
          for ( count = 0; count < 3; count++, stems += 2 )
          {
            error = ps_dimension_add_t1stem( dim,
                                             (FT_Int)FIXED_TO_INT( stems[0] ),
                                             (FT_Int)FIXED_TO_INT( stems[1] ),
                                             memory, &idx[count] );
            if ( error )
              goto Fail;
          }
  
          /* now, add the hints to the counters table */
          error = ps_dimension_add_counter( dim, idx[0], idx[1], idx[2],
                                            memory );
          if ( error )
            goto Fail;
        }
        else
        {
          FT_ERROR(( "ps_hints_t1stem3: called with invalid hint type\n" ));
          error = FT_THROW( Invalid_Argument );
          goto Fail;
        }
      }
  
      return;
  
    Fail:
      FT_ERROR(( "ps_hints_t1stem3: could not add counter stems to table\n" ));
      hints->error = error;
    }
  
  
    /* reset hints (only with Type 1 hints) */
    static void
    ps_hints_t1reset( PS_Hints  hints,
                      FT_UInt   end_point )
    {
      FT_Error  error = FT_Err_Ok;
  
  
      if ( !hints->error )
      {
        FT_Memory  memory = hints->memory;
  
  
        if ( hints->hint_type == PS_HINT_TYPE_1 )
        {
          error = ps_dimension_reset_mask( &hints->dimension[0],
                                           end_point, memory );
          if ( error )
            goto Fail;
  
          error = ps_dimension_reset_mask( &hints->dimension[1],
                                           end_point, memory );
          if ( error )
            goto Fail;
        }
        else
        {
          /* invalid hint type */
          error = FT_THROW( Invalid_Argument );
          goto Fail;
        }
      }
      return;
  
    Fail:
      hints->error = error;
    }
  
  
    /* Type2 "hintmask" operator, add a new hintmask to each direction */
    static void
    ps_hints_t2mask( PS_Hints        hints,
                     FT_UInt         end_point,
                     FT_UInt         bit_count,
                     const FT_Byte*  bytes )
    {
      FT_Error  error;
  
  
      if ( !hints->error )
      {
        PS_Dimension  dim    = hints->dimension;
        FT_Memory     memory = hints->memory;
        FT_UInt       count1 = dim[0].hints.num_hints;
        FT_UInt       count2 = dim[1].hints.num_hints;
  
  
        /* check bit count; must be equal to current total hint count */
        if ( bit_count !=  count1 + count2 )
        {
          FT_TRACE0(( "ps_hints_t2mask:"
                      " called with invalid bitcount %d (instead of %d)\n",
                     bit_count, count1 + count2 ));
  
          /* simply ignore the operator */
          return;
        }
  
        /* set-up new horizontal and vertical hint mask now */
        error = ps_dimension_set_mask_bits( &dim[0], bytes, count2, count1,
                                            end_point, memory );
        if ( error )
          goto Fail;
  
        error = ps_dimension_set_mask_bits( &dim[1], bytes, 0, count2,
                                            end_point, memory );
        if ( error )
          goto Fail;
      }
      return;
  
    Fail:
      hints->error = error;
    }
  
  
    static void
    ps_hints_t2counter( PS_Hints        hints,
                        FT_UInt         bit_count,
                        const FT_Byte*  bytes )
    {
      FT_Error  error;
  
  
      if ( !hints->error )
      {
        PS_Dimension  dim    = hints->dimension;
        FT_Memory     memory = hints->memory;
        FT_UInt       count1 = dim[0].hints.num_hints;
        FT_UInt       count2 = dim[1].hints.num_hints;
  
  
        /* check bit count, must be equal to current total hint count */
        if ( bit_count !=  count1 + count2 )
        {
          FT_TRACE0(( "ps_hints_t2counter:"
                      " called with invalid bitcount %d (instead of %d)\n",
                     bit_count, count1 + count2 ));
  
          /* simply ignore the operator */
          return;
        }
  
        /* set-up new horizontal and vertical hint mask now */
        error = ps_dimension_set_mask_bits( &dim[0], bytes, 0, count1,
                                            0, memory );
        if ( error )
          goto Fail;
  
        error = ps_dimension_set_mask_bits( &dim[1], bytes, count1, count2,
                                            0, memory );
        if ( error )
          goto Fail;
      }
      return;
  
    Fail:
      hints->error = error;
    }
  
  
    /* end recording session */
    static FT_Error
    ps_hints_close( PS_Hints  hints,
                    FT_UInt   end_point )
    {
      FT_Error  error;
  
  
      error = hints->error;
      if ( !error )
      {
        FT_Memory     memory = hints->memory;
        PS_Dimension  dim    = hints->dimension;
  
  
        error = ps_dimension_end( &dim[0], end_point, memory );
        if ( !error )
        {
          error = ps_dimension_end( &dim[1], end_point, memory );
        }
      }
  
  #ifdef DEBUG_HINTER
      if ( !error )
        ps_debug_hints = hints;
  #endif
      return error;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                TYPE 1 HINTS RECORDING INTERFACE               *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    static void
    t1_hints_open( T1_Hints  hints )
    {
      ps_hints_open( (PS_Hints)hints, PS_HINT_TYPE_1 );
    }
  
    static void
    t1_hints_stem( T1_Hints   hints,
                   FT_UInt    dimension,
                   FT_Fixed*  coords )
    {
      FT_Pos  stems[2];
  
  
      stems[0] = FIXED_TO_INT( coords[0] );
      stems[1] = FIXED_TO_INT( coords[1] );
  
      ps_hints_stem( (PS_Hints)hints, dimension, 1, stems );
    }
  
  
    FT_LOCAL_DEF( void )
    t1_hints_funcs_init( T1_Hints_FuncsRec*  funcs )
    {
      FT_ZERO( funcs );
  
      funcs->open  = (T1_Hints_OpenFunc)    t1_hints_open;
      funcs->close = (T1_Hints_CloseFunc)   ps_hints_close;
      funcs->stem  = (T1_Hints_SetStemFunc) t1_hints_stem;
      funcs->stem3 = (T1_Hints_SetStem3Func)ps_hints_t1stem3;
      funcs->reset = (T1_Hints_ResetFunc)   ps_hints_t1reset;
      funcs->apply = (T1_Hints_ApplyFunc)   ps_hints_apply;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                TYPE 2 HINTS RECORDING INTERFACE               *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    static void
    t2_hints_open( T2_Hints  hints )
    {
      ps_hints_open( (PS_Hints)hints, PS_HINT_TYPE_2 );
    }
  
  
    static void
    t2_hints_stems( T2_Hints   hints,
                    FT_UInt    dimension,
                    FT_Int     count,
                    FT_Fixed*  coords )
    {
      FT_Pos  stems[32], y;
      FT_Int  total = count, n;
  
  
      y = 0;
      while ( total > 0 )
      {
        /* determine number of stems to write */
        count = total;
        if ( count > 16 )
          count = 16;
  
        /* compute integer stem positions in font units */
        for ( n = 0; n < count * 2; n++ )
        {
          y        = ADD_LONG( y, coords[n] );
          stems[n] = FIXED_TO_INT( y );
        }
  
        /* compute lengths */
        for ( n = 0; n < count * 2; n += 2 )
          stems[n + 1] = stems[n + 1] - stems[n];
  
        /* add them to the current dimension */
        ps_hints_stem( (PS_Hints)hints, dimension, count, stems );
  
        total -= count;
      }
    }
  
  
    FT_LOCAL_DEF( void )
    t2_hints_funcs_init( T2_Hints_FuncsRec*  funcs )
    {
      FT_ZERO( funcs );
  
      funcs->open    = (T2_Hints_OpenFunc)   t2_hints_open;
      funcs->close   = (T2_Hints_CloseFunc)  ps_hints_close;
      funcs->stems   = (T2_Hints_StemsFunc)  t2_hints_stems;
      funcs->hintmask= (T2_Hints_MaskFunc)   ps_hints_t2mask;
      funcs->counter = (T2_Hints_CounterFunc)ps_hints_t2counter;
      funcs->apply   = (T2_Hints_ApplyFunc)  ps_hints_apply;
    }
  
  
  /* END */
  