pfrgload.c

winNT技术操作系统,国外开放的原代码和LIUX一样

          args_count  = 4;
          args_format = format & 15;
        }

        /***********************************************************/
        /*  now read arguments                                     */
        /*                                                         */
        cur = pos;
        for ( n = 0; n < args_count; n++ )
        {
          FT_Int  idx, delta;


          /* read the X argument */
          switch ( args_format & 3 )
          {
          case 0:                           /* 8-bit index */
            PFR_CHECK( 1 );
            idx  = PFR_NEXT_BYTE( p );
            cur->x = glyph->x_control[idx];
            FT_TRACE7(( " cx#%d", idx ));
            break;

          case 1:                           /* 16-bit value */
            PFR_CHECK( 2 );
            cur->x = PFR_NEXT_SHORT( p );
            FT_TRACE7(( " x.%d", cur->x ));
            break;

          case 2:                           /* 8-bit delta */
            PFR_CHECK( 1 );
            delta  = PFR_NEXT_INT8( p );
            cur->x = pos[3].x + delta;
            FT_TRACE7(( " dx.%d", delta ));
            break;

          default:
            FT_TRACE7(( " |" ));
            cur->x = pos[3].x;
          }

          /* read the Y argument */
          switch ( ( args_format >> 2 ) & 3 )
          {
          case 0:                           /* 8-bit index */
            PFR_CHECK( 1 );
            idx  = PFR_NEXT_BYTE( p );
            cur->y = glyph->y_control[idx];
            FT_TRACE7(( " cy#%d", idx ));
            break;

          case 1:                           /* 16-bit absolute value */
            PFR_CHECK( 2 );
            cur->y = PFR_NEXT_SHORT( p );
            FT_TRACE7(( " y.%d", cur->y ));
            break;

          case 2:                           /* 8-bit delta */
            PFR_CHECK( 1 );
            delta  = PFR_NEXT_INT8( p );
            cur->y = pos[3].y + delta;
            FT_TRACE7(( " dy.%d", delta ));
            break;

          default:
            FT_TRACE7(( " -" ));
            cur->y = pos[3].y;
          }

          /* read the additional format flag for the general curve */
          if ( n == 0 && args_count == 4 )
          {
            PFR_CHECK( 1 );
            args_format = PFR_NEXT_BYTE( p );
            args_count--;
          }
          else
            args_format >>= 4;

          /* save the previous point */
          pos[3] = cur[0];
          cur++;
        }

        FT_TRACE7(( "\n" ));

        /***********************************************************/
        /*  finally, execute instruction                           */
        /*                                                         */
        switch ( format >> 4 )
        {
        case 0:                             /* end glyph => EXIT */
          pfr_glyph_end( glyph );
          goto Exit;

        case 1:                             /* line operations */
        case 2:
        case 3:
          error = pfr_glyph_line_to( glyph, pos );
          goto Test_Error;

        case 4:                             /* move to inside contour  */
        case 5:                             /* move to outside contour */
          error = pfr_glyph_move_to( glyph, pos );
          goto Test_Error;

        default:                            /* curve operations */
          error = pfr_glyph_curve_to( glyph, pos, pos + 1, pos + 2 );

        Test_Error:  /* test error condition */
          if ( error )
            goto Exit;
        }
      } /* for (;;) */
    }

  Exit:
    return error;

  Too_Short:
    error = PFR_Err_Invalid_Table;
    FT_ERROR(( "pfr_glyph_load_simple: invalid glyph data\n" ));
    goto Exit;
  }


  /* load a composite/compound glyph */
  static FT_Error
  pfr_glyph_load_compound( PFR_Glyph  glyph,
                           FT_Byte*   p,
                           FT_Byte*   limit )
  {
    FT_Error        error  = 0;
    FT_GlyphLoader  loader = glyph->loader;
    FT_Memory       memory = loader->memory;
    PFR_SubGlyph    subglyph;
    FT_UInt         flags, i, count, org_count;
    FT_Int          x_pos, y_pos;


    PFR_CHECK( 1 );
    flags = PFR_NEXT_BYTE( p );

    /* test for composite glyphs */
    FT_ASSERT( ( flags & PFR_GLYPH_IS_COMPOUND ) != 0 );

    count = flags & 0x3F;

    /* ignore extra items when present */
    /*                                 */
    if ( flags & PFR_GLYPH_EXTRA_ITEMS )
    {
      error = pfr_extra_items_skip( &p, limit );
      if (error) goto Exit;
    }

    /* we can't rely on the FT_GlyphLoader to load sub-glyphs, because   */
    /* the PFR format is dumb, using direct file offsets to point to the */
    /* sub-glyphs (instead of glyph indices).  Sigh.                     */
    /*                                                                   */
    /* For now, we load the list of sub-glyphs into a different array    */
    /* but this will prevent us from using the auto-hinter at its best   */
    /* quality.                                                          */
    /*                                                                   */
    org_count = glyph->num_subs;

    if ( org_count + count > glyph->max_subs )
    {
      FT_UInt  new_max = ( org_count + count + 3 ) & -4;


      if ( FT_RENEW_ARRAY( glyph->subs, glyph->max_subs, new_max ) )
        goto Exit;

      glyph->max_subs = new_max;
    }

    subglyph = glyph->subs + org_count;

    for ( i = 0; i < count; i++, subglyph++ )
    {
      FT_UInt  format;


      x_pos = 0;
      y_pos = 0;

      PFR_CHECK( 1 );
      format = PFR_NEXT_BYTE( p );

      /* read scale when available */
      subglyph->x_scale = 0x10000L;
      if ( format & PFR_SUBGLYPH_XSCALE )
      {
        PFR_CHECK( 2 );
        subglyph->x_scale = PFR_NEXT_SHORT( p ) << 4;
      }

      subglyph->y_scale = 0x10000L;
      if ( format & PFR_SUBGLYPH_YSCALE )
      {
        PFR_CHECK( 2 );
        subglyph->y_scale = PFR_NEXT_SHORT( p ) << 4;
      }

      /* read offset */
      switch ( format & 3 )
      {
      case 1:
        PFR_CHECK( 2 );
        x_pos = PFR_NEXT_SHORT( p );
        break;

      case 2:
        PFR_CHECK( 1 );
        x_pos += PFR_NEXT_INT8( p );
        break;

      default:
        ;
      }

      switch ( ( format >> 2 ) & 3 )
      {
      case 1:
        PFR_CHECK( 2 );
        y_pos = PFR_NEXT_SHORT( p );
        break;

      case 2:
        PFR_CHECK( 1 );
        y_pos += PFR_NEXT_INT8( p );
        break;

      default:
        ;
      }

      subglyph->x_delta = x_pos;
      subglyph->y_delta = y_pos;

      /* read glyph position and size now */
      if ( format & PFR_SUBGLYPH_2BYTE_SIZE )
      {
        PFR_CHECK( 2 );
        subglyph->gps_size = PFR_NEXT_USHORT( p );
      }
      else
      {
        PFR_CHECK( 1 );
        subglyph->gps_size = PFR_NEXT_BYTE( p );
      }

      if ( format & PFR_SUBGLYPH_3BYTE_OFFSET )
      {
        PFR_CHECK( 3 );
        subglyph->gps_offset = PFR_NEXT_LONG( p );
      }
      else
      {
        PFR_CHECK( 2 );
        subglyph->gps_offset = PFR_NEXT_USHORT( p );
      }

      glyph->num_subs++;
    }

  Exit:
    return error;

  Too_Short:
    error = PFR_Err_Invalid_Table;
    FT_ERROR(( "pfr_glyph_load_compound: invalid glyph data\n" ));
    goto Exit;
  }





  static FT_Error
  pfr_glyph_load_rec( PFR_Glyph  glyph,
                      FT_Stream  stream,
                      FT_ULong   gps_offset,
                      FT_ULong   offset,
                      FT_ULong   size )
  {
    FT_Error  error;
    FT_Byte*  p;
    FT_Byte*  limit;


    if ( FT_STREAM_SEEK( gps_offset + offset ) ||
         FT_FRAME_ENTER( size )                )
      goto Exit;

    p     = (FT_Byte*)stream->cursor;
    limit = p + size;

    if ( size > 0 && *p & PFR_GLYPH_IS_COMPOUND )
    {
      FT_Int          n, old_count, count;
      FT_GlyphLoader  loader = glyph->loader;
      FT_Outline*     base   = &loader->base.outline;


      old_count = glyph->num_subs;

      /* this is a compound glyph - load it */
      error = pfr_glyph_load_compound( glyph, p, limit );

      FT_FRAME_EXIT();

      if ( error )
        goto Exit;

      count = glyph->num_subs - old_count;

      /* now, load each individual glyph */
      for ( n = 0; n < count; n++ )
      {
        FT_Int        i, old_points, num_points;
        PFR_SubGlyph  subglyph;


        subglyph   = glyph->subs + old_count + n;
        old_points = base->n_points;

        error = pfr_glyph_load_rec( glyph, stream, gps_offset,
                                    subglyph->gps_offset,
                                    subglyph->gps_size );
        if ( error )
          goto Exit;

        /* note that `glyph->subs' might have been re-allocated */
        subglyph   = glyph->subs + old_count + n;
        num_points = base->n_points - old_points;

        /* translate and eventually scale the new glyph points */
        if ( subglyph->x_scale != 0x10000L || subglyph->y_scale != 0x10000L )
        {
          FT_Vector*  vec = base->points + old_points;


          for ( i = 0; i < num_points; i++, vec++ )
          {
            vec->x = FT_MulFix( vec->x, subglyph->x_scale ) +
                       subglyph->x_delta;
            vec->y = FT_MulFix( vec->y, subglyph->y_scale ) +
                       subglyph->y_delta;
          }
        }
        else
        {
          FT_Vector*  vec = loader->base.outline.points + old_points;


          for ( i = 0; i < num_points; i++, vec++ )
          {
            vec->x += subglyph->x_delta;
            vec->y += subglyph->y_delta;
          }
        }

        /* proceed to next sub-glyph */
      }
    }
    else
    {
      /* load a simple glyph */
      error = pfr_glyph_load_simple( glyph, p, limit );

      FT_FRAME_EXIT();
    }

  Exit:
    return error;
  }





  FT_LOCAL_DEF( FT_Error )
  pfr_glyph_load( PFR_Glyph  glyph,
                  FT_Stream  stream,
                  FT_ULong   gps_offset,
                  FT_ULong   offset,
                  FT_ULong   size )
  {
    /* initialize glyph loader */
    FT_GlyphLoader_Rewind( glyph->loader );

    glyph->num_subs = 0;

    /* load the glyph, recursively when needed */
    return pfr_glyph_load_rec( glyph, stream, gps_offset, offset, size );
  }


/* END */