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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  pshrec.c                                                               */
      4 /*                                                                         */
      5 /*    FreeType PostScript hints recorder (body).                           */
      6 /*                                                                         */
      7 /*  Copyright 2001-2004, 2007, 2009, 2013 by                               */
      8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
      9 /*                                                                         */
     10 /*  This file is part of the FreeType project, and may only be used,       */
     11 /*  modified, and distributed under the terms of the FreeType project      */
     12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
     13 /*  this file you indicate that you have read the license and              */
     14 /*  understand and accept it fully.                                        */
     15 /*                                                                         */
     16 /***************************************************************************/
     17 
     18 
     19 #include <ft2build.h>
     20 #include FT_FREETYPE_H
     21 #include FT_INTERNAL_OBJECTS_H
     22 #include FT_INTERNAL_DEBUG_H
     23 #include FT_INTERNAL_CALC_H
     24 
     25 #include "pshrec.h"
     26 #include "pshalgo.h"
     27 
     28 #include "pshnterr.h"
     29 
     30 #undef  FT_COMPONENT
     31 #define FT_COMPONENT  trace_pshrec
     32 
     33 #ifdef DEBUG_HINTER
     34   PS_Hints  ps_debug_hints         = 0;
     35   int       ps_debug_no_horz_hints = 0;
     36   int       ps_debug_no_vert_hints = 0;
     37 #endif
     38 
     39 
     40   /*************************************************************************/
     41   /*************************************************************************/
     42   /*****                                                               *****/
     43   /*****                      PS_HINT MANAGEMENT                       *****/
     44   /*****                                                               *****/
     45   /*************************************************************************/
     46   /*************************************************************************/
     47 
     48   /* destroy hints table */
     49   static void
     50   ps_hint_table_done( PS_Hint_Table  table,
     51                       FT_Memory      memory )
     52   {
     53     FT_FREE( table->hints );
     54     table->num_hints = 0;
     55     table->max_hints = 0;
     56   }
     57 
     58 
     59   /* ensure that a table can contain "count" elements */
     60   static FT_Error
     61   ps_hint_table_ensure( PS_Hint_Table  table,
     62                         FT_UInt        count,
     63                         FT_Memory      memory )
     64   {
     65     FT_UInt   old_max = table->max_hints;
     66     FT_UInt   new_max = count;
     67     FT_Error  error   = FT_Err_Ok;
     68 
     69 
     70     if ( new_max > old_max )
     71     {
     72       /* try to grow the table */
     73       new_max = FT_PAD_CEIL( new_max, 8 );
     74       if ( !FT_RENEW_ARRAY( table->hints, old_max, new_max ) )
     75         table->max_hints = new_max;
     76     }
     77     return error;
     78   }
     79 
     80 
     81   static FT_Error
     82   ps_hint_table_alloc( PS_Hint_Table  table,
     83                        FT_Memory      memory,
     84                        PS_Hint       *ahint )
     85   {
     86     FT_Error  error = FT_Err_Ok;
     87     FT_UInt   count;
     88     PS_Hint   hint = 0;
     89 
     90 
     91     count = table->num_hints;
     92     count++;
     93 
     94     if ( count >= table->max_hints )
     95     {
     96       error = ps_hint_table_ensure( table, count, memory );
     97       if ( error )
     98         goto Exit;
     99     }
    100 
    101     hint        = table->hints + count - 1;
    102     hint->pos   = 0;
    103     hint->len   = 0;
    104     hint->flags = 0;
    105 
    106     table->num_hints = count;
    107 
    108   Exit:
    109     *ahint = hint;
    110     return error;
    111   }
    112 
    113 
    114   /*************************************************************************/
    115   /*************************************************************************/
    116   /*****                                                               *****/
    117   /*****                      PS_MASK MANAGEMENT                       *****/
    118   /*****                                                               *****/
    119   /*************************************************************************/
    120   /*************************************************************************/
    121 
    122   /* destroy mask */
    123   static void
    124   ps_mask_done( PS_Mask    mask,
    125                 FT_Memory  memory )
    126   {
    127     FT_FREE( mask->bytes );
    128     mask->num_bits  = 0;
    129     mask->max_bits  = 0;
    130     mask->end_point = 0;
    131   }
    132 
    133 
    134   /* ensure that a mask can contain "count" bits */
    135   static FT_Error
    136   ps_mask_ensure( PS_Mask    mask,
    137                   FT_UInt    count,
    138                   FT_Memory  memory )
    139   {
    140     FT_UInt   old_max = ( mask->max_bits + 7 ) >> 3;
    141     FT_UInt   new_max = ( count          + 7 ) >> 3;
    142     FT_Error  error   = FT_Err_Ok;
    143 
    144 
    145     if ( new_max > old_max )
    146     {
    147       new_max = FT_PAD_CEIL( new_max, 8 );
    148       if ( !FT_RENEW_ARRAY( mask->bytes, old_max, new_max ) )
    149         mask->max_bits = new_max * 8;
    150     }
    151     return error;
    152   }
    153 
    154 
    155   /* test a bit value in a given mask */
    156   static FT_Int
    157   ps_mask_test_bit( PS_Mask  mask,
    158                     FT_Int   idx )
    159   {
    160     if ( (FT_UInt)idx >= mask->num_bits )
    161       return 0;
    162 
    163     return mask->bytes[idx >> 3] & ( 0x80 >> ( idx & 7 ) );
    164   }
    165 
    166 
    167   /* clear a given bit */
    168   static void
    169   ps_mask_clear_bit( PS_Mask  mask,
    170                      FT_Int   idx )
    171   {
    172     FT_Byte*  p;
    173 
    174 
    175     if ( (FT_UInt)idx >= mask->num_bits )
    176       return;
    177 
    178     p    = mask->bytes + ( idx >> 3 );
    179     p[0] = (FT_Byte)( p[0] & ~( 0x80 >> ( idx & 7 ) ) );
    180   }
    181 
    182 
    183   /* set a given bit, possibly grow the mask */
    184   static FT_Error
    185   ps_mask_set_bit( PS_Mask    mask,
    186                    FT_Int     idx,
    187                    FT_Memory  memory )
    188   {
    189     FT_Error  error = FT_Err_Ok;
    190     FT_Byte*  p;
    191 
    192 
    193     if ( idx < 0 )
    194       goto Exit;
    195 
    196     if ( (FT_UInt)idx >= mask->num_bits )
    197     {
    198       error = ps_mask_ensure( mask, idx + 1, memory );
    199       if ( error )
    200         goto Exit;
    201 
    202       mask->num_bits = idx + 1;
    203     }
    204 
    205     p    = mask->bytes + ( idx >> 3 );
    206     p[0] = (FT_Byte)( p[0] | ( 0x80 >> ( idx & 7 ) ) );
    207 
    208   Exit:
    209     return error;
    210   }
    211 
    212 
    213   /* destroy mask table */
    214   static void
    215   ps_mask_table_done( PS_Mask_Table  table,
    216                       FT_Memory      memory )
    217   {
    218     FT_UInt  count = table->max_masks;
    219     PS_Mask  mask  = table->masks;
    220 
    221 
    222     for ( ; count > 0; count--, mask++ )
    223       ps_mask_done( mask, memory );
    224 
    225     FT_FREE( table->masks );
    226     table->num_masks = 0;
    227     table->max_masks = 0;
    228   }
    229 
    230 
    231   /* ensure that a mask table can contain "count" masks */
    232   static FT_Error
    233   ps_mask_table_ensure( PS_Mask_Table  table,
    234                         FT_UInt        count,
    235                         FT_Memory      memory )
    236   {
    237     FT_UInt   old_max = table->max_masks;
    238     FT_UInt   new_max = count;
    239     FT_Error  error   = FT_Err_Ok;
    240 
    241 
    242     if ( new_max > old_max )
    243     {
    244       new_max = FT_PAD_CEIL( new_max, 8 );
    245       if ( !FT_RENEW_ARRAY( table->masks, old_max, new_max ) )
    246         table->max_masks = new_max;
    247     }
    248     return error;
    249   }
    250 
    251 
    252   /* allocate a new mask in a table */
    253   static FT_Error
    254   ps_mask_table_alloc( PS_Mask_Table  table,
    255                        FT_Memory      memory,
    256                        PS_Mask       *amask )
    257   {
    258     FT_UInt   count;
    259     FT_Error  error = FT_Err_Ok;
    260     PS_Mask   mask  = 0;
    261 
    262 
    263     count = table->num_masks;
    264     count++;
    265 
    266     if ( count > table->max_masks )
    267     {
    268       error = ps_mask_table_ensure( table, count, memory );
    269       if ( error )
    270         goto Exit;
    271     }
    272 
    273     mask             = table->masks + count - 1;
    274     mask->num_bits   = 0;
    275     mask->end_point  = 0;
    276     table->num_masks = count;
    277 
    278   Exit:
    279     *amask = mask;
    280     return error;
    281   }
    282 
    283 
    284   /* return last hint mask in a table, create one if the table is empty */
    285   static FT_Error
    286   ps_mask_table_last( PS_Mask_Table  table,
    287                       FT_Memory      memory,
    288                       PS_Mask       *amask )
    289   {
    290     FT_Error  error = FT_Err_Ok;
    291     FT_UInt   count;
    292     PS_Mask   mask;
    293 
    294 
    295     count = table->num_masks;
    296     if ( count == 0 )
    297     {
    298       error = ps_mask_table_alloc( table, memory, &mask );
    299       if ( error )
    300         goto Exit;
    301     }
    302     else
    303       mask = table->masks + count - 1;
    304 
    305   Exit:
    306     *amask = mask;
    307     return error;
    308   }
    309 
    310 
    311   /* set a new mask to a given bit range */
    312   static FT_Error
    313   ps_mask_table_set_bits( PS_Mask_Table   table,
    314                           const FT_Byte*  source,
    315                           FT_UInt         bit_pos,
    316                           FT_UInt         bit_count,
    317                           FT_Memory       memory )
    318   {
    319     FT_Error  error;
    320     PS_Mask   mask;
    321 
    322 
    323     error = ps_mask_table_last( table, memory, &mask );
    324     if ( error )
    325       goto Exit;
    326 
    327     error = ps_mask_ensure( mask, bit_count, memory );
    328     if ( error )
    329       goto Exit;
    330 
    331     mask->num_bits = bit_count;
    332 
    333     /* now, copy bits */
    334     {
    335       FT_Byte*  read  = (FT_Byte*)source + ( bit_pos >> 3 );
    336       FT_Int    rmask = 0x80 >> ( bit_pos & 7 );
    337       FT_Byte*  write = mask->bytes;
    338       FT_Int    wmask = 0x80;
    339       FT_Int    val;
    340 
    341 
    342       for ( ; bit_count > 0; bit_count-- )
    343       {
    344         val = write[0] & ~wmask;
    345 
    346         if ( read[0] & rmask )
    347           val |= wmask;
    348 
    349         write[0] = (FT_Byte)val;
    350 
    351         rmask >>= 1;
    352         if ( rmask == 0 )
    353         {
    354           read++;
    355           rmask = 0x80;
    356         }
    357 
    358         wmask >>= 1;
    359         if ( wmask == 0 )
    360         {
    361           write++;
    362           wmask = 0x80;
    363         }
    364       }
    365     }
    366 
    367   Exit:
    368     return error;
    369   }
    370 
    371 
    372   /* test whether two masks in a table intersect */
    373   static FT_Int
    374   ps_mask_table_test_intersect( PS_Mask_Table  table,
    375                                 FT_Int         index1,
    376                                 FT_Int         index2 )
    377   {
    378     PS_Mask   mask1  = table->masks + index1;
    379     PS_Mask   mask2  = table->masks + index2;
    380     FT_Byte*  p1     = mask1->bytes;
    381     FT_Byte*  p2     = mask2->bytes;
    382     FT_UInt   count1 = mask1->num_bits;
    383     FT_UInt   count2 = mask2->num_bits;
    384     FT_UInt   count;
    385 
    386 
    387     count = FT_MIN( count1, count2 );
    388     for ( ; count >= 8; count -= 8 )
    389     {
    390       if ( p1[0] & p2[0] )
    391         return 1;
    392 
    393       p1++;
    394       p2++;
    395     }
    396 
    397     if ( count == 0 )
    398       return 0;
    399 
    400     return ( p1[0] & p2[0] ) & ~( 0xFF >> count );
    401   }
    402 
    403 
    404   /* merge two masks, used by ps_mask_table_merge_all */
    405   static FT_Error
    406   ps_mask_table_merge( PS_Mask_Table  table,
    407                        FT_Int         index1,
    408                        FT_Int         index2,
    409                        FT_Memory      memory )
    410   {
    411     FT_UInt   temp;
    412     FT_Error  error = FT_Err_Ok;
    413 
    414 
    415     /* swap index1 and index2 so that index1 < index2 */
    416     if ( index1 > index2 )
    417     {
    418       temp   = index1;
    419       index1 = index2;
    420       index2 = temp;
    421     }
    422 
    423     if ( index1 < index2 && index1 >= 0 && index2 < (FT_Int)table->num_masks )
    424     {
    425       /* we need to merge the bitsets of index1 and index2 with a */
    426       /* simple union                                             */
    427       PS_Mask  mask1  = table->masks + index1;
    428       PS_Mask  mask2  = table->masks + index2;
    429       FT_UInt  count1 = mask1->num_bits;
    430       FT_UInt  count2 = mask2->num_bits;
    431       FT_Int   delta;
    432 
    433 
    434       if ( count2 > 0 )
    435       {
    436         FT_UInt   pos;
    437         FT_Byte*  read;
    438         FT_Byte*  write;
    439 
    440 
    441         /* if "count2" is greater than "count1", we need to grow the */
    442         /* first bitset, and clear the highest bits                  */
    443         if ( count2 > count1 )
    444         {
    445           error = ps_mask_ensure( mask1, count2, memory );
    446           if ( error )
    447             goto Exit;
    448 
    449           for ( pos = count1; pos < count2; pos++ )
    450             ps_mask_clear_bit( mask1, pos );
    451         }
    452 
    453         /* merge (unite) the bitsets */
    454         read  = mask2->bytes;
    455         write = mask1->bytes;
    456         pos   = (FT_UInt)( ( count2 + 7 ) >> 3 );
    457 
    458         for ( ; pos > 0; pos-- )
    459         {
    460           write[0] = (FT_Byte)( write[0] | read[0] );
    461           write++;
    462           read++;
    463         }
    464       }
    465 
    466       /* Now, remove "mask2" from the list.  We need to keep the masks */
    467       /* sorted in order of importance, so move table elements.        */
    468       mask2->num_bits  = 0;
    469       mask2->end_point = 0;
    470 
    471       delta = table->num_masks - 1 - index2; /* number of masks to move */
    472       if ( delta > 0 )
    473       {
    474         /* move to end of table for reuse */
    475         PS_MaskRec  dummy = *mask2;
    476 
    477 
    478         ft_memmove( mask2, mask2 + 1, delta * sizeof ( PS_MaskRec ) );
    479 
    480         mask2[delta] = dummy;
    481       }
    482 
    483       table->num_masks--;
    484     }
    485     else
    486       FT_TRACE0(( "ps_mask_table_merge: ignoring invalid indices (%d,%d)\n",
    487                   index1, index2 ));
    488 
    489   Exit:
    490     return error;
    491   }
    492 
    493 
    494   /* Try to merge all masks in a given table.  This is used to merge */
    495   /* all counter masks into independent counter "paths".             */
    496   /*                                                                 */
    497   static FT_Error
    498   ps_mask_table_merge_all( PS_Mask_Table  table,
    499                            FT_Memory      memory )
    500   {
    501     FT_Int    index1, index2;
    502     FT_Error  error = FT_Err_Ok;
    503 
    504 
    505     for ( index1 = table->num_masks - 1; index1 > 0; index1-- )
    506     {
    507       for ( index2 = index1 - 1; index2 >= 0; index2-- )
    508       {
    509         if ( ps_mask_table_test_intersect( table, index1, index2 ) )
    510         {
    511           error = ps_mask_table_merge( table, index2, index1, memory );
    512           if ( error )
    513             goto Exit;
    514 
    515           break;
    516         }
    517       }
    518     }
    519 
    520   Exit:
    521     return error;
    522   }
    523 
    524 
    525   /*************************************************************************/
    526   /*************************************************************************/
    527   /*****                                                               *****/
    528   /*****                    PS_DIMENSION MANAGEMENT                    *****/
    529   /*****                                                               *****/
    530   /*************************************************************************/
    531   /*************************************************************************/
    532 
    533 
    534   /* finalize a given dimension */
    535   static void
    536   ps_dimension_done( PS_Dimension  dimension,
    537                      FT_Memory     memory )
    538   {
    539     ps_mask_table_done( &dimension->counters, memory );
    540     ps_mask_table_done( &dimension->masks,    memory );
    541     ps_hint_table_done( &dimension->hints,    memory );
    542   }
    543 
    544 
    545   /* initialize a given dimension */
    546   static void
    547   ps_dimension_init( PS_Dimension  dimension )
    548   {
    549     dimension->hints.num_hints    = 0;
    550     dimension->masks.num_masks    = 0;
    551     dimension->counters.num_masks = 0;
    552   }
    553 
    554 
    555 #if 0
    556 
    557   /* set a bit at a given index in the current hint mask */
    558   static FT_Error
    559   ps_dimension_set_mask_bit( PS_Dimension  dim,
    560                              FT_UInt       idx,
    561                              FT_Memory     memory )
    562   {
    563     PS_Mask   mask;
    564     FT_Error  error = FT_Err_Ok;
    565 
    566 
    567     /* get last hint mask */
    568     error = ps_mask_table_last( &dim->masks, memory, &mask );
    569     if ( error )
    570       goto Exit;
    571 
    572     error = ps_mask_set_bit( mask, idx, memory );
    573 
    574   Exit:
    575     return error;
    576   }
    577 
    578 #endif
    579 
    580   /* set the end point in a mask, called from "End" & "Reset" methods */
    581   static void
    582   ps_dimension_end_mask( PS_Dimension  dim,
    583                          FT_UInt       end_point )
    584   {
    585     FT_UInt  count = dim->masks.num_masks;
    586 
    587 
    588     if ( count > 0 )
    589     {
    590       PS_Mask  mask = dim->masks.masks + count - 1;
    591 
    592 
    593       mask->end_point = end_point;
    594     }
    595   }
    596 
    597 
    598   /* set the end point in the current mask, then create a new empty one */
    599   /* (called by "Reset" method)                                         */
    600   static FT_Error
    601   ps_dimension_reset_mask( PS_Dimension  dim,
    602                            FT_UInt       end_point,
    603                            FT_Memory     memory )
    604   {
    605     PS_Mask  mask;
    606 
    607 
    608     /* end current mask */
    609     ps_dimension_end_mask( dim, end_point );
    610 
    611     /* allocate new one */
    612     return ps_mask_table_alloc( &dim->masks, memory, &mask );
    613   }
    614 
    615 
    616   /* set a new mask, called from the "T2Stem" method */
    617   static FT_Error
    618   ps_dimension_set_mask_bits( PS_Dimension    dim,
    619                               const FT_Byte*  source,
    620                               FT_UInt         source_pos,
    621                               FT_UInt         source_bits,
    622                               FT_UInt         end_point,
    623                               FT_Memory       memory )
    624   {
    625     FT_Error  error;
    626 
    627 
    628     /* reset current mask, if any */
    629     error = ps_dimension_reset_mask( dim, end_point, memory );
    630     if ( error )
    631       goto Exit;
    632 
    633     /* set bits in new mask */
    634     error = ps_mask_table_set_bits( &dim->masks, source,
    635                                     source_pos, source_bits, memory );
    636 
    637   Exit:
    638     return error;
    639   }
    640 
    641 
    642   /* add a new single stem (called from "T1Stem" method) */
    643   static FT_Error
    644   ps_dimension_add_t1stem( PS_Dimension  dim,
    645                            FT_Int        pos,
    646                            FT_Int        len,
    647                            FT_Memory     memory,
    648                            FT_Int       *aindex )
    649   {
    650     FT_Error  error = FT_Err_Ok;
    651     FT_UInt   flags = 0;
    652 
    653 
    654     /* detect ghost stem */
    655     if ( len < 0 )
    656     {
    657       flags |= PS_HINT_FLAG_GHOST;
    658       if ( len == -21 )
    659       {
    660         flags |= PS_HINT_FLAG_BOTTOM;
    661         pos   += len;
    662       }
    663       len = 0;
    664     }
    665 
    666     if ( aindex )
    667       *aindex = -1;
    668 
    669     /* now, lookup stem in the current hints table */
    670     {
    671       PS_Mask  mask;
    672       FT_UInt  idx;
    673       FT_UInt  max   = dim->hints.num_hints;
    674       PS_Hint  hint  = dim->hints.hints;
    675 
    676 
    677       for ( idx = 0; idx < max; idx++, hint++ )
    678       {
    679         if ( hint->pos == pos && hint->len == len )
    680           break;
    681       }
    682 
    683       /* we need to create a new hint in the table */
    684       if ( idx >= max )
    685       {
    686         error = ps_hint_table_alloc( &dim->hints, memory, &hint );
    687         if ( error )
    688           goto Exit;
    689 
    690         hint->pos   = pos;
    691         hint->len   = len;
    692         hint->flags = flags;
    693       }
    694 
    695       /* now, store the hint in the current mask */
    696       error = ps_mask_table_last( &dim->masks, memory, &mask );
    697       if ( error )
    698         goto Exit;
    699 
    700       error = ps_mask_set_bit( mask, idx, memory );
    701       if ( error )
    702         goto Exit;
    703 
    704       if ( aindex )
    705         *aindex = (FT_Int)idx;
    706     }
    707 
    708   Exit:
    709     return error;
    710   }
    711 
    712 
    713   /* add a "hstem3/vstem3" counter to our dimension table */
    714   static FT_Error
    715   ps_dimension_add_counter( PS_Dimension  dim,
    716                             FT_Int        hint1,
    717                             FT_Int        hint2,
    718                             FT_Int        hint3,
    719                             FT_Memory     memory )
    720   {
    721     FT_Error  error   = FT_Err_Ok;
    722     FT_UInt   count   = dim->counters.num_masks;
    723     PS_Mask   counter = dim->counters.masks;
    724 
    725 
    726     /* try to find an existing counter mask that already uses */
    727     /* one of these stems here                                */
    728     for ( ; count > 0; count--, counter++ )
    729     {
    730       if ( ps_mask_test_bit( counter, hint1 ) ||
    731            ps_mask_test_bit( counter, hint2 ) ||
    732            ps_mask_test_bit( counter, hint3 ) )
    733         break;
    734     }
    735 
    736     /* create a new counter when needed */
    737     if ( count == 0 )
    738     {
    739       error = ps_mask_table_alloc( &dim->counters, memory, &counter );
    740       if ( error )
    741         goto Exit;
    742     }
    743 
    744     /* now, set the bits for our hints in the counter mask */
    745     error = ps_mask_set_bit( counter, hint1, memory );
    746     if ( error )
    747       goto Exit;
    748 
    749     error = ps_mask_set_bit( counter, hint2, memory );
    750     if ( error )
    751       goto Exit;
    752 
    753     error = ps_mask_set_bit( counter, hint3, memory );
    754     if ( error )
    755       goto Exit;
    756 
    757   Exit:
    758     return error;
    759   }
    760 
    761 
    762   /* end of recording session for a given dimension */
    763   static FT_Error
    764   ps_dimension_end( PS_Dimension  dim,
    765                     FT_UInt       end_point,
    766                     FT_Memory     memory )
    767   {
    768     /* end hint mask table */
    769     ps_dimension_end_mask( dim, end_point );
    770 
    771     /* merge all counter masks into independent "paths" */
    772     return ps_mask_table_merge_all( &dim->counters, memory );
    773   }
    774 
    775 
    776   /*************************************************************************/
    777   /*************************************************************************/
    778   /*****                                                               *****/
    779   /*****                    PS_RECORDER MANAGEMENT                     *****/
    780   /*****                                                               *****/
    781   /*************************************************************************/
    782   /*************************************************************************/
    783 
    784 
    785   /* destroy hints */
    786   FT_LOCAL( void )
    787   ps_hints_done( PS_Hints  hints )
    788   {
    789     FT_Memory  memory = hints->memory;
    790 
    791 
    792     ps_dimension_done( &hints->dimension[0], memory );
    793     ps_dimension_done( &hints->dimension[1], memory );
    794 
    795     hints->error  = FT_Err_Ok;
    796     hints->memory = 0;
    797   }
    798 
    799 
    800   FT_LOCAL( FT_Error )
    801   ps_hints_init( PS_Hints   hints,
    802                  FT_Memory  memory )
    803   {
    804     FT_MEM_ZERO( hints, sizeof ( *hints ) );
    805     hints->memory = memory;
    806     return FT_Err_Ok;
    807   }
    808 
    809 
    810   /* initialize a hints for a new session */
    811   static void
    812   ps_hints_open( PS_Hints      hints,
    813                  PS_Hint_Type  hint_type )
    814   {
    815     switch ( hint_type )
    816     {
    817     case PS_HINT_TYPE_1:
    818     case PS_HINT_TYPE_2:
    819       hints->error     = FT_Err_Ok;
    820       hints->hint_type = hint_type;
    821 
    822       ps_dimension_init( &hints->dimension[0] );
    823       ps_dimension_init( &hints->dimension[1] );
    824       break;
    825 
    826     default:
    827       hints->error     = FT_THROW( Invalid_Argument );
    828       hints->hint_type = hint_type;
    829 
    830       FT_TRACE0(( "ps_hints_open: invalid charstring type\n" ));
    831       break;
    832     }
    833   }
    834 
    835 
    836   /* add one or more stems to the current hints table */
    837   static void
    838   ps_hints_stem( PS_Hints  hints,
    839                  FT_Int    dimension,
    840                  FT_UInt   count,
    841                  FT_Long*  stems )
    842   {
    843     if ( !hints->error )
    844     {
    845       /* limit "dimension" to 0..1 */
    846       if ( dimension < 0 || dimension > 1 )
    847       {
    848         FT_TRACE0(( "ps_hints_stem: invalid dimension (%d) used\n",
    849                     dimension ));
    850         dimension = ( dimension != 0 );
    851       }
    852 
    853       /* record the stems in the current hints/masks table */
    854       switch ( hints->hint_type )
    855       {
    856       case PS_HINT_TYPE_1:  /* Type 1 "hstem" or "vstem" operator */
    857       case PS_HINT_TYPE_2:  /* Type 2 "hstem" or "vstem" operator */
    858         {
    859           PS_Dimension  dim = &hints->dimension[dimension];
    860 
    861 
    862           for ( ; count > 0; count--, stems += 2 )
    863           {
    864             FT_Error   error;
    865             FT_Memory  memory = hints->memory;
    866 
    867 
    868             error = ps_dimension_add_t1stem(
    869                       dim, (FT_Int)stems[0], (FT_Int)stems[1],
    870                       memory, NULL );
    871             if ( error )
    872             {
    873               FT_ERROR(( "ps_hints_stem: could not add stem"
    874                          " (%d,%d) to hints table\n", stems[0], stems[1] ));
    875 
    876               hints->error = error;
    877               return;
    878             }
    879           }
    880           break;
    881         }
    882 
    883       default:
    884         FT_TRACE0(( "ps_hints_stem: called with invalid hint type (%d)\n",
    885                     hints->hint_type ));
    886         break;
    887       }
    888     }
    889   }
    890 
    891 
    892   /* add one Type1 counter stem to the current hints table */
    893   static void
    894   ps_hints_t1stem3( PS_Hints   hints,
    895                     FT_Int     dimension,
    896                     FT_Fixed*  stems )
    897   {
    898     FT_Error  error = FT_Err_Ok;
    899 
    900 
    901     if ( !hints->error )
    902     {
    903       PS_Dimension  dim;
    904       FT_Memory     memory = hints->memory;
    905       FT_Int        count;
    906       FT_Int        idx[3];
    907 
    908 
    909       /* limit "dimension" to 0..1 */
    910       if ( dimension < 0 || dimension > 1 )
    911       {
    912         FT_TRACE0(( "ps_hints_t1stem3: invalid dimension (%d) used\n",
    913                     dimension ));
    914         dimension = ( dimension != 0 );
    915       }
    916 
    917       dim = &hints->dimension[dimension];
    918 
    919       /* there must be 6 elements in the 'stem' array */
    920       if ( hints->hint_type == PS_HINT_TYPE_1 )
    921       {
    922         /* add the three stems to our hints/masks table */
    923         for ( count = 0; count < 3; count++, stems += 2 )
    924         {
    925           error = ps_dimension_add_t1stem( dim,
    926                                            (FT_Int)FIXED_TO_INT( stems[0] ),
    927                                            (FT_Int)FIXED_TO_INT( stems[1] ),
    928                                            memory, &idx[count] );
    929           if ( error )
    930             goto Fail;
    931         }
    932 
    933         /* now, add the hints to the counters table */
    934         error = ps_dimension_add_counter( dim, idx[0], idx[1], idx[2],
    935                                           memory );
    936         if ( error )
    937           goto Fail;
    938       }
    939       else
    940       {
    941         FT_ERROR(( "ps_hints_t1stem3: called with invalid hint type\n" ));
    942         error = FT_THROW( Invalid_Argument );
    943         goto Fail;
    944       }
    945     }
    946 
    947     return;
    948 
    949   Fail:
    950     FT_ERROR(( "ps_hints_t1stem3: could not add counter stems to table\n" ));
    951     hints->error = error;
    952   }
    953 
    954 
    955   /* reset hints (only with Type 1 hints) */
    956   static void
    957   ps_hints_t1reset( PS_Hints  hints,
    958                     FT_UInt   end_point )
    959   {
    960     FT_Error  error = FT_Err_Ok;
    961 
    962 
    963     if ( !hints->error )
    964     {
    965       FT_Memory  memory = hints->memory;
    966 
    967 
    968       if ( hints->hint_type == PS_HINT_TYPE_1 )
    969       {
    970         error = ps_dimension_reset_mask( &hints->dimension[0],
    971                                          end_point, memory );
    972         if ( error )
    973           goto Fail;
    974 
    975         error = ps_dimension_reset_mask( &hints->dimension[1],
    976                                          end_point, memory );
    977         if ( error )
    978           goto Fail;
    979       }
    980       else
    981       {
    982         /* invalid hint type */
    983         error = FT_THROW( Invalid_Argument );
    984         goto Fail;
    985       }
    986     }
    987     return;
    988 
    989   Fail:
    990     hints->error = error;
    991   }
    992 
    993 
    994   /* Type2 "hintmask" operator, add a new hintmask to each direction */
    995   static void
    996   ps_hints_t2mask( PS_Hints        hints,
    997                    FT_UInt         end_point,
    998                    FT_UInt         bit_count,
    999                    const FT_Byte*  bytes )
   1000   {
   1001     FT_Error  error;
   1002 
   1003 
   1004     if ( !hints->error )
   1005     {
   1006       PS_Dimension  dim    = hints->dimension;
   1007       FT_Memory     memory = hints->memory;
   1008       FT_UInt       count1 = dim[0].hints.num_hints;
   1009       FT_UInt       count2 = dim[1].hints.num_hints;
   1010 
   1011 
   1012       /* check bit count; must be equal to current total hint count */
   1013       if ( bit_count !=  count1 + count2 )
   1014       {
   1015         FT_TRACE0(( "ps_hints_t2mask:"
   1016                     " called with invalid bitcount %d (instead of %d)\n",
   1017                    bit_count, count1 + count2 ));
   1018 
   1019         /* simply ignore the operator */
   1020         return;
   1021       }
   1022 
   1023       /* set-up new horizontal and vertical hint mask now */
   1024       error = ps_dimension_set_mask_bits( &dim[0], bytes, count2, count1,
   1025                                           end_point, memory );
   1026       if ( error )
   1027         goto Fail;
   1028 
   1029       error = ps_dimension_set_mask_bits( &dim[1], bytes, 0, count2,
   1030                                           end_point, memory );
   1031       if ( error )
   1032         goto Fail;
   1033     }
   1034     return;
   1035 
   1036   Fail:
   1037     hints->error = error;
   1038   }
   1039 
   1040 
   1041   static void
   1042   ps_hints_t2counter( PS_Hints        hints,
   1043                       FT_UInt         bit_count,
   1044                       const FT_Byte*  bytes )
   1045   {
   1046     FT_Error  error;
   1047 
   1048 
   1049     if ( !hints->error )
   1050     {
   1051       PS_Dimension  dim    = hints->dimension;
   1052       FT_Memory     memory = hints->memory;
   1053       FT_UInt       count1 = dim[0].hints.num_hints;
   1054       FT_UInt       count2 = dim[1].hints.num_hints;
   1055 
   1056 
   1057       /* check bit count, must be equal to current total hint count */
   1058       if ( bit_count !=  count1 + count2 )
   1059       {
   1060         FT_TRACE0(( "ps_hints_t2counter:"
   1061                     " called with invalid bitcount %d (instead of %d)\n",
   1062                    bit_count, count1 + count2 ));
   1063 
   1064         /* simply ignore the operator */
   1065         return;
   1066       }
   1067 
   1068       /* set-up new horizontal and vertical hint mask now */
   1069       error = ps_dimension_set_mask_bits( &dim[0], bytes, 0, count1,
   1070                                           0, memory );
   1071       if ( error )
   1072         goto Fail;
   1073 
   1074       error = ps_dimension_set_mask_bits( &dim[1], bytes, count1, count2,
   1075                                           0, memory );
   1076       if ( error )
   1077         goto Fail;
   1078     }
   1079     return;
   1080 
   1081   Fail:
   1082     hints->error = error;
   1083   }
   1084 
   1085 
   1086   /* end recording session */
   1087   static FT_Error
   1088   ps_hints_close( PS_Hints  hints,
   1089                   FT_UInt   end_point )
   1090   {
   1091     FT_Error  error;
   1092 
   1093 
   1094     error = hints->error;
   1095     if ( !error )
   1096     {
   1097       FT_Memory     memory = hints->memory;
   1098       PS_Dimension  dim    = hints->dimension;
   1099 
   1100 
   1101       error = ps_dimension_end( &dim[0], end_point, memory );
   1102       if ( !error )
   1103       {
   1104         error = ps_dimension_end( &dim[1], end_point, memory );
   1105       }
   1106     }
   1107 
   1108 #ifdef DEBUG_HINTER
   1109     if ( !error )
   1110       ps_debug_hints = hints;
   1111 #endif
   1112     return error;
   1113   }
   1114 
   1115 
   1116   /*************************************************************************/
   1117   /*************************************************************************/
   1118   /*****                                                               *****/
   1119   /*****                TYPE 1 HINTS RECORDING INTERFACE               *****/
   1120   /*****                                                               *****/
   1121   /*************************************************************************/
   1122   /*************************************************************************/
   1123 
   1124   static void
   1125   t1_hints_open( T1_Hints  hints )
   1126   {
   1127     ps_hints_open( (PS_Hints)hints, PS_HINT_TYPE_1 );
   1128   }
   1129 
   1130   static void
   1131   t1_hints_stem( T1_Hints   hints,
   1132                  FT_Int     dimension,
   1133                  FT_Fixed*  coords )
   1134   {
   1135     FT_Pos  stems[2];
   1136 
   1137 
   1138     stems[0] = FIXED_TO_INT( coords[0] );
   1139     stems[1] = FIXED_TO_INT( coords[1] );
   1140 
   1141     ps_hints_stem( (PS_Hints)hints, dimension, 1, stems );
   1142   }
   1143 
   1144 
   1145   FT_LOCAL_DEF( void )
   1146   t1_hints_funcs_init( T1_Hints_FuncsRec*  funcs )
   1147   {
   1148     FT_MEM_ZERO( (char*)funcs, sizeof ( *funcs ) );
   1149 
   1150     funcs->open  = (T1_Hints_OpenFunc)    t1_hints_open;
   1151     funcs->close = (T1_Hints_CloseFunc)   ps_hints_close;
   1152     funcs->stem  = (T1_Hints_SetStemFunc) t1_hints_stem;
   1153     funcs->stem3 = (T1_Hints_SetStem3Func)ps_hints_t1stem3;
   1154     funcs->reset = (T1_Hints_ResetFunc)   ps_hints_t1reset;
   1155     funcs->apply = (T1_Hints_ApplyFunc)   ps_hints_apply;
   1156   }
   1157 
   1158 
   1159   /*************************************************************************/
   1160   /*************************************************************************/
   1161   /*****                                                               *****/
   1162   /*****                TYPE 2 HINTS RECORDING INTERFACE               *****/
   1163   /*****                                                               *****/
   1164   /*************************************************************************/
   1165   /*************************************************************************/
   1166 
   1167   static void
   1168   t2_hints_open( T2_Hints  hints )
   1169   {
   1170     ps_hints_open( (PS_Hints)hints, PS_HINT_TYPE_2 );
   1171   }
   1172 
   1173 
   1174   static void
   1175   t2_hints_stems( T2_Hints   hints,
   1176                   FT_Int     dimension,
   1177                   FT_Int     count,
   1178                   FT_Fixed*  coords )
   1179   {
   1180     FT_Pos  stems[32], y, n;
   1181     FT_Int  total = count;
   1182 
   1183 
   1184     y = 0;
   1185     while ( total > 0 )
   1186     {
   1187       /* determine number of stems to write */
   1188       count = total;
   1189       if ( count > 16 )
   1190         count = 16;
   1191 
   1192       /* compute integer stem positions in font units */
   1193       for ( n = 0; n < count * 2; n++ )
   1194       {
   1195         y       += coords[n];
   1196         stems[n] = FIXED_TO_INT( y );
   1197       }
   1198 
   1199       /* compute lengths */
   1200       for ( n = 0; n < count * 2; n += 2 )
   1201         stems[n + 1] = stems[n + 1] - stems[n];
   1202 
   1203       /* add them to the current dimension */
   1204       ps_hints_stem( (PS_Hints)hints, dimension, count, stems );
   1205 
   1206       total -= count;
   1207     }
   1208   }
   1209 
   1210 
   1211   FT_LOCAL_DEF( void )
   1212   t2_hints_funcs_init( T2_Hints_FuncsRec*  funcs )
   1213   {
   1214     FT_MEM_ZERO( funcs, sizeof ( *funcs ) );
   1215 
   1216     funcs->open    = (T2_Hints_OpenFunc)   t2_hints_open;
   1217     funcs->close   = (T2_Hints_CloseFunc)  ps_hints_close;
   1218     funcs->stems   = (T2_Hints_StemsFunc)  t2_hints_stems;
   1219     funcs->hintmask= (T2_Hints_MaskFunc)   ps_hints_t2mask;
   1220     funcs->counter = (T2_Hints_CounterFunc)ps_hints_t2counter;
   1221     funcs->apply   = (T2_Hints_ApplyFunc)  ps_hints_apply;
   1222   }
   1223 
   1224 
   1225 /* END */
   1226