pshinter.c

ucgui的矢量字库支持包,可以象windows一样使用truetype的字库了

                         PSH_Blue_Table  bot_table )
  {
    FT_UInt  count_top = top_table->count;
    FT_UInt  count_bot = bot_table->count;
    FT_Bool  first     = 1;

    FT_UNUSED( target );


    for ( ; read_count > 1; read_count -= 2 )
    {
      FT_Int         reference, delta;
      FT_UInt        count;
      PSH_Blue_Zone  zones, zone;
      FT_Bool        top;


      /* read blue zone entry, and select target top/bottom zone */
      top = 0;
      if ( first || is_others )
      {
        reference = read[1];
        delta     = read[0] - reference;

        zones = bot_table->zones;
        count = count_bot;
        first = 0;
      }
      else
      {
        reference = read[0];
        delta     = read[1] - reference;

        zones = top_table->zones;
        count = count_top;
        top   = 1;
      }

      /* insert into sorted table */
      zone = zones;
      for ( ; count > 0; count--, zone++ )
      {
        if ( reference < zone->org_ref )
          break;

        if ( reference == zone->org_ref )
        {
          FT_Int  delta0 = zone->org_delta;


          /* we have two zones on the same reference position -- */
          /* only keep the largest one                           */
          if ( delta < 0 )
          {
            if ( delta < delta0 )
              zone->org_delta = delta;
          }
          else
          {
            if ( delta > delta0 )
              zone->org_delta = delta;
          }
          goto Skip;
        }
      }

      for ( ; count > 0; count-- )
        zone[count] = zone[count-1];

      zone->org_ref   = reference;
      zone->org_delta = delta;

      if ( top )
        count_top++;
      else
        count_bot++;

    Skip:
      read += 2;
    }

    top_table->count = count_top;
    bot_table->count = count_bot;
  }


  /* Re-read blue zones from the original fonts and store them into out */
  /* private structure.  This function re-orders, sanitizes and         */
  /* fuzz-expands the zones as well.                                    */
  static void
  psh_blues_set_zones( PSH_Blues  target,
                       FT_UInt    count,
                       FT_Short*  blues,
                       FT_UInt    count_others,
                       FT_Short*  other_blues,
                       FT_Int     fuzz,
                       FT_Int     family )
  {
    PSH_Blue_Table  top_table, bot_table;
    FT_Int          count_top, count_bot;


    if ( family )
    {
      top_table = &target->family_top;
      bot_table = &target->family_bottom;
    }
    else
    {
      top_table = &target->normal_top;
      bot_table = &target->normal_bottom;
    }

    /* read the input blue zones, and build two sorted tables  */
    /* (one for the top zones, the other for the bottom zones) */
    top_table->count = 0;
    bot_table->count = 0;

    /* first, the blues */
    psh_blues_set_zones_0( target, 0,
                           count, blues, top_table, bot_table );
    psh_blues_set_zones_0( target, 1,
                           count_others, other_blues, top_table, bot_table );

    count_top = top_table->count;
    count_bot = bot_table->count;

    /* sanitize top table */
    if ( count_top > 0 )
    {
      PSH_Blue_Zone  zone = top_table->zones;


      for ( count = count_top; count > 0; count--, zone++ )
      {
        FT_Int  delta;


        if ( count > 1 )
        {
          delta = zone[1].org_ref - zone[0].org_ref;
          if ( zone->org_delta > delta )
            zone->org_delta = delta;
        }

        zone->org_bottom = zone->org_ref;
        zone->org_top    = zone->org_delta + zone->org_ref;
      }
    }

    /* sanitize bottom table */
    if ( count_bot > 0 )
    {
      PSH_Blue_Zone  zone = bot_table->zones;


      for ( count = count_bot; count > 0; count--, zone++ )
      {
        FT_Int  delta;


        if ( count > 1 )
        {
          delta = zone[0].org_ref - zone[1].org_ref;
          if ( zone->org_delta < delta )
            zone->org_delta = delta;
        }

        zone->org_top    = zone->org_ref;
        zone->org_bottom = zone->org_delta + zone->org_ref;
      }
    }

    /* expand top and bottom tables with blue fuzz */
    {
      FT_Int         dim, top, bot, delta;
      PSH_Blue_Zone  zone;


      zone  = top_table->zones;
      count = count_top;

      for ( dim = 1; dim >= 0; dim-- )
      {
        if ( count > 0 )
        {
          /* expand the bottom of the lowest zone normally */
          zone->org_bottom -= fuzz;

          /* expand the top and bottom of intermediate zones;    */
          /* checking that the interval is smaller than the fuzz */
          top = zone->org_top;

          for ( count--; count > 0; count-- )
          {
            bot   = zone[1].org_bottom;
            delta = bot - top;

            if ( delta < 2 * fuzz )
              zone[0].org_top = zone[1].org_bottom = top + delta / 2;
            else
            {
              zone[0].org_top    = top + fuzz;
              zone[1].org_bottom = bot - fuzz;
            }

            zone++;
            top = zone->org_top;
          }

          /* expand the top of the highest zone normally */
          zone->org_top = top + fuzz;
        }
        zone  = bot_table->zones;
        count = count_bot;
      }
    }
  }


  /* reset the blues table when the device transform changes */
  static void
  psh_blues_scale_zones( PSH_Blues  blues,
                         FT_Fixed   scale,
                         FT_Pos     delta )
  {
    FT_UInt         count;
    FT_UInt         num;
    PSH_Blue_Table  table = 0;

    /*                                                        */
    /* Determine whether we need to suppress overshoots or    */
    /* not.  We simply need to compare the vertical scale     */
    /* parameter to the raw bluescale value.  Here is why:    */
    /*                                                        */
    /*   We need to suppress overshoots for all pointsizes.   */
    /*   At 300dpi that satisfies:                            */
    /*                                                        */
    /*      pointsize < 240*bluescale + 0.49                  */
    /*                                                        */
    /*   This corresponds to:                                 */
    /*                                                        */
    /*      pixelsize < 1000*bluescale + 49/24                */
    /*                                                        */
    /*      scale*EM_Size < 1000*bluescale + 49/24            */
    /*                                                        */
    /*   However, for normal Type 1 fonts, EM_Size is 1000!   */
    /*   We thus only check:                                  */
    /*                                                        */
    /*      scale < bluescale + 49/24000                      */
    /*                                                        */
    /*   which we shorten to                                  */
    /*                                                        */
    /*      "scale < bluescale"                               */
    /*                                                        */
    /* Note that `blue_scale' is stored 1000 times its real   */
    /* value, and that `scale' converts from font units to    */
    /* fractional pixels.                                     */
    /*                                                        */

    /* 1000 / 64 = 125 / 8 */
    if ( scale >= 0x20C49BAL )
      blues->no_overshoots = FT_BOOL( scale < blues->blue_scale * 8 / 125 );
    else
      blues->no_overshoots = FT_BOOL( scale * 125 < blues->blue_scale * 8 );

    /*                                                        */
    /*  The blue threshold is the font units distance under   */
    /*  which overshoots are suppressed due to the BlueShift  */
    /*  even if the scale is greater than BlueScale.          */
    /*                                                        */
    /*  It is the smallest distance such that                 */
    /*                                                        */
    /*    dist <= BlueShift && dist*scale <= 0.5 pixels       */
    /*                                                        */
    {
      FT_Int  threshold = blues->blue_shift;


      while ( threshold > 0 && FT_MulFix( threshold, scale ) > 32 )
        threshold--;

      blues->blue_threshold = threshold;
    }

    for ( num = 0; num < 4; num++ )
    {
      PSH_Blue_Zone  zone;


      switch ( num )
      {
      case 0:
        table = &blues->normal_top;
        break;
      case 1:
        table = &blues->normal_bottom;
        break;
      case 2:
        table = &blues->family_top;
        break;
      default:
        table = &blues->family_bottom;
        break;
      }

      zone  = table->zones;
      count = table->count;
      for ( ; count > 0; count--, zone++ )
      {
        zone->cur_top    = FT_MulFix( zone->org_top,    scale ) + delta;
        zone->cur_bottom = FT_MulFix( zone->org_bottom, scale ) + delta;
        zone->cur_ref    = FT_MulFix( zone->org_ref,    scale ) + delta;
        zone->cur_delta  = FT_MulFix( zone->org_delta,  scale );

        /* round scaled reference position */
        zone->cur_ref = FT_PIX_ROUND( zone->cur_ref );

#if 0
        if ( zone->cur_ref > zone->cur_top )
          zone->cur_ref -= 64;
        else if ( zone->cur_ref < zone->cur_bottom )
          zone->cur_ref += 64;
#endif
      }
    }

    /* process the families now */

    for ( num = 0; num < 2; num++ )
    {
      PSH_Blue_Zone   zone1, zone2;
      FT_UInt         count1, count2;
      PSH_Blue_Table  normal, family;


      switch ( num )
      {
      case 0:
        normal = &blues->normal_top;
        family = &blues->family_top;
        break;

      default:
        normal = &blues->normal_bottom;
        family = &blues->family_bottom;
      }

      zone1  = normal->zones;
      count1 = normal->count;

      for ( ; count1 > 0; count1--, zone1++ )
      {
        /* try to find a family zone whose reference position is less */
        /* than 1 pixel far from the current zone                     */
        zone2  = family->zones;
        count2 = family->count;

        for ( ; count2 > 0; count2--, zone2++ )
        {
          FT_Pos  Delta;


          Delta = zone1->org_ref - zone2->org_ref;
          if ( Delta < 0 )
            Delta = -Delta;

          if ( FT_MulFix( Delta, scale ) < 64 )
          {
            zone1->cur_top    = zone2->cur_top;
            zone1->cur_bottom = zone2->cur_bottom;
            zone1->cur_ref    = zone2->cur_ref;
            zone1->cur_delta  = zone2->cur_delta;
            break;
          }
        }
      }
    }
  }


  FT_LOCAL_DEF( void )
  psh_blues_snap_stem( PSH_Blues      blues,
                       FT_Int         stem_top,
                       FT_Int         stem_bot,
                       PSH_Alignment  alignment )
  {
    PSH_Blue_Table  table;
    FT_UInt         count;
    FT_Pos          delta;
    PSH_Blue_Zone   zone;
    FT_Int          no_shoots;


    alignment->align = PSH_BLUE_ALIGN_NONE;

    no_shoots = blues->no_overshoots;

    /* look up stem top in top zones table */
    table = &blues->normal_top;
    count = table->count;
    zone  = table->zones;

    for ( ; count > 0; count--, zone++ )
    {
      delta = stem_top - zone->org_bottom;
      if ( delta < -blues->blue_fuzz )
        break;

      if ( stem_top <= zone->org_top + blues->blue_fuzz )
      {
        if ( no_shoots || delta <= blues->blue_threshold )
        {
          alignment->align    |= PSH_BLUE_ALIGN_TOP;
          alignment->align_top = zone->cur_ref;
        }
        break;
      }
    }

    /* look up stem bottom in bottom zones table */
    table = &blues->normal_bottom;
    count = table->count;
    zone  = table->zones + count-1;

    for ( ; count > 0; count--, zone-- )
    {
      delta = zone->org_top - stem_bot;
      if ( delta < -blues->blue_fuzz )
        break;

      if ( stem_bot >= zone->org_bottom - blues->blue_fuzz )
      {
        if ( no_shoots || delta < blues->blue_threshold )
        {
          alignment->align    |= PSH_BLUE_ALIGN_BOT;
          alignment->align_bot = zone->cur_ref;
        }
        break;
      }
    }
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                        GLOBAL HINTS                           *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  static void
  psh_globals_destroy( PSH_Globals  globals )
  {
    if ( globals )
    {
      FT_Memory  memory;