pcfread.c

下载来的一个看图软件的源代码

                  ( metrics + i )->descent,
                  ( metrics + i )->attributes ));

      if ( error )
        break;
    }

    if ( error )
      FT_FREE( face->metrics );
    return error;
  }


  static FT_Error
  pcf_get_bitmaps( FT_Stream  stream,
                   PCF_Face   face )
  {
    FT_Error   error  = PCF_Err_Ok;
    FT_Memory  memory = FT_FACE(face)->memory;
    FT_Long*   offsets;
    FT_Long    bitmapSizes[GLYPHPADOPTIONS];
    FT_ULong   format, size;
    int        nbitmaps, i, sizebitmaps = 0;
    char*      bitmaps;


    error = pcf_seek_to_table_type( stream,
                                    face->toc.tables,
                                    face->toc.count,
                                    PCF_BITMAPS,
                                    &format,
                                    &size );
    if ( error )
      return error;

    error = FT_Stream_EnterFrame( stream, 8 );
    if ( error )
      return error;

    format = FT_GET_ULONG_LE();
    if ( PCF_BYTE_ORDER( format ) == MSBFirst )
      nbitmaps  = FT_GET_ULONG();
    else
      nbitmaps  = FT_GET_ULONG_LE();

    FT_Stream_ExitFrame( stream );

    if ( !PCF_FORMAT_MATCH( format, PCF_DEFAULT_FORMAT ) )
      return PCF_Err_Invalid_File_Format;

    if ( nbitmaps != face->nmetrics )
      return PCF_Err_Invalid_File_Format;

    if ( FT_NEW_ARRAY( offsets, nbitmaps ) )
      return error;

    for ( i = 0; i < nbitmaps; i++ )
    {
      if ( PCF_BYTE_ORDER( format ) == MSBFirst )
        (void)FT_READ_LONG( offsets[i] );
      else
        (void)FT_READ_LONG_LE( offsets[i] );

      FT_TRACE4(( "bitmap %d is at offset %ld\n", i, offsets[i] ));
    }
    if ( error )
      goto Bail;

    for ( i = 0; i < GLYPHPADOPTIONS; i++ )
    {
      if ( PCF_BYTE_ORDER( format ) == MSBFirst )
        (void)FT_READ_LONG( bitmapSizes[i] );
      else
        (void)FT_READ_LONG_LE( bitmapSizes[i] );
      if ( error )
        goto Bail;

      sizebitmaps = bitmapSizes[PCF_GLYPH_PAD_INDEX( format )];

      FT_TRACE4(( "padding %d implies a size of %ld\n", i, bitmapSizes[i] ));
    }

    FT_TRACE4(( "  %d bitmaps, padding index %ld\n",
                nbitmaps,
                PCF_GLYPH_PAD_INDEX( format ) ));
    FT_TRACE4(( "bitmap size = %d\n", sizebitmaps ));

    FT_UNUSED( sizebitmaps );       /* only used for debugging */

    for ( i = 0; i < nbitmaps; i++ )
      face->metrics[i].bits = stream->pos + offsets[i];

    face->bitmapsFormat = format;

    FT_FREE ( offsets );
    return error;

  Bail:
    FT_FREE ( offsets );
    FT_FREE ( bitmaps );
    return error;
  }


  static FT_Error
  pcf_get_encodings( FT_Stream  stream,
                     PCF_Face   face )
  {
    FT_Error      error   = PCF_Err_Ok;
    FT_Memory     memory  = FT_FACE(face)->memory;
    FT_ULong      format, size;
    int           firstCol, lastCol;
    int           firstRow, lastRow;
    int           nencoding, encodingOffset;
    int           i, j;
    PCF_Encoding  tmpEncoding, encoding = 0;


    error = pcf_seek_to_table_type( stream,
                                    face->toc.tables,
                                    face->toc.count,
                                    PCF_BDF_ENCODINGS,
                                    &format,
                                    &size );
    if ( error )
      return error;

    error = FT_Stream_EnterFrame( stream, 14 );
    if ( error )
      return error;

    format = FT_GET_ULONG_LE();

    if ( PCF_BYTE_ORDER( format ) == MSBFirst )
    {
      firstCol          = FT_GET_SHORT();
      lastCol           = FT_GET_SHORT();
      firstRow          = FT_GET_SHORT();
      lastRow           = FT_GET_SHORT();
      face->defaultChar = FT_GET_SHORT();
    }
    else
    {
      firstCol          = FT_GET_SHORT_LE();
      lastCol           = FT_GET_SHORT_LE();
      firstRow          = FT_GET_SHORT_LE();
      lastRow           = FT_GET_SHORT_LE();
      face->defaultChar = FT_GET_SHORT_LE();
    }

    FT_Stream_ExitFrame( stream );

    if ( !PCF_FORMAT_MATCH( format, PCF_DEFAULT_FORMAT ) )
      return PCF_Err_Invalid_File_Format;

    FT_TRACE4(( "enc: firstCol %d, lastCol %d, firstRow %d, lastRow %d\n",
                firstCol, lastCol, firstRow, lastRow ));

    nencoding = ( lastCol - firstCol + 1 ) * ( lastRow - firstRow + 1 );

    if ( FT_NEW_ARRAY( tmpEncoding, nencoding ) )
      return PCF_Err_Out_Of_Memory;

    error = FT_Stream_EnterFrame( stream, 2 * nencoding );
    if ( error )
      goto Bail;

    for ( i = 0, j = 0 ; i < nencoding; i++ )
    {
      if ( PCF_BYTE_ORDER( format ) == MSBFirst )
        encodingOffset = FT_GET_SHORT();
      else
        encodingOffset = FT_GET_SHORT_LE();

      if ( encodingOffset != -1 )
      {
        tmpEncoding[j].enc = ( ( ( i / ( lastCol - firstCol + 1 ) ) +
                                 firstRow ) * 256 ) +
                               ( ( i % ( lastCol - firstCol + 1 ) ) +
                                 firstCol );

        tmpEncoding[j].glyph = (FT_Short)encodingOffset;
        j++;
      }

      FT_TRACE4(( "enc n. %d ; Uni %ld ; Glyph %d\n",
                  i, tmpEncoding[j - 1].enc, encodingOffset ));
    }
    FT_Stream_ExitFrame( stream );

    if ( FT_NEW_ARRAY( encoding, j ) )
      goto Bail;

    for ( i = 0; i < j; i++ )
    {
      encoding[i].enc   = tmpEncoding[i].enc;
      encoding[i].glyph = tmpEncoding[i].glyph;
    }

    face->nencodings = j;
    face->encodings  = encoding;
    FT_FREE( tmpEncoding );

    return error;

  Bail:
    FT_FREE( encoding );
    FT_FREE( tmpEncoding );
    return error;
  }


  static
  const FT_Frame_Field  pcf_accel_header[] =
  {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  PCF_AccelRec

    FT_FRAME_START( 20 ),
      FT_FRAME_BYTE      ( noOverlap ),
      FT_FRAME_BYTE      ( constantMetrics ),
      FT_FRAME_BYTE      ( terminalFont ),
      FT_FRAME_BYTE      ( constantWidth ),
      FT_FRAME_BYTE      ( inkInside ),
      FT_FRAME_BYTE      ( inkMetrics ),
      FT_FRAME_BYTE      ( drawDirection ),
      FT_FRAME_SKIP_BYTES( 1 ),
      FT_FRAME_LONG_LE   ( fontAscent ),
      FT_FRAME_LONG_LE   ( fontDescent ),
      FT_FRAME_LONG_LE   ( maxOverlap ),
    FT_FRAME_END
  };


  static
  const FT_Frame_Field  pcf_accel_msb_header[] =
  {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  PCF_AccelRec

    FT_FRAME_START( 20 ),
      FT_FRAME_BYTE      ( noOverlap ),
      FT_FRAME_BYTE      ( constantMetrics ),
      FT_FRAME_BYTE      ( terminalFont ),
      FT_FRAME_BYTE      ( constantWidth ),
      FT_FRAME_BYTE      ( inkInside ),
      FT_FRAME_BYTE      ( inkMetrics ),
      FT_FRAME_BYTE      ( drawDirection ),
      FT_FRAME_SKIP_BYTES( 1 ),
      FT_FRAME_LONG      ( fontAscent ),
      FT_FRAME_LONG      ( fontDescent ),
      FT_FRAME_LONG      ( maxOverlap ),
    FT_FRAME_END
  };


  static FT_Error
  pcf_get_accel( FT_Stream  stream,
                 PCF_Face   face,
                 FT_ULong   type )
  {
    FT_ULong   format, size;
    FT_Error   error = PCF_Err_Ok;
    PCF_Accel  accel = &face->accel;


    error = pcf_seek_to_table_type( stream,
                                    face->toc.tables,
                                    face->toc.count,
                                    type,
                                    &format,
                                    &size );
    if ( error )
      goto Bail;

    error = FT_READ_ULONG_LE( format );

    if ( !PCF_FORMAT_MATCH( format, PCF_DEFAULT_FORMAT )    &&
         !PCF_FORMAT_MATCH( format, PCF_ACCEL_W_INKBOUNDS ) )
      goto Bail;

    if ( PCF_BYTE_ORDER( format ) == MSBFirst )
    {
      if ( FT_STREAM_READ_FIELDS( pcf_accel_msb_header, accel ) )
        goto Bail;
    }
    else
    {
      if ( FT_STREAM_READ_FIELDS( pcf_accel_header, accel ) )
        goto Bail;
    }

    error = pcf_get_metric( stream,
                            format & ( ~PCF_FORMAT_MASK ),
                            &(accel->minbounds) );
    if ( error )
      goto Bail;

    error = pcf_get_metric( stream,
                            format & ( ~PCF_FORMAT_MASK ),
                            &(accel->maxbounds) );
    if ( error )
      goto Bail;

    if ( PCF_FORMAT_MATCH( format, PCF_ACCEL_W_INKBOUNDS ) )
    {
      error = pcf_get_metric( stream,
                              format & ( ~PCF_FORMAT_MASK ),
                              &(accel->ink_minbounds) );
      if ( error )
        goto Bail;

      error = pcf_get_metric( stream,
                              format & ( ~PCF_FORMAT_MASK ),
                              &(accel->ink_maxbounds) );
      if ( error )
        goto Bail;
    }
    else
    {
      accel->ink_minbounds = accel->minbounds; /* I'm not sure about this */
      accel->ink_maxbounds = accel->maxbounds;
    }
    return error;

  Bail:
    return error;
  }


  FT_LOCAL_DEF( FT_Error )
  pcf_load_font( FT_Stream  stream,
                 PCF_Face   face )
  {
    FT_Error   error  = PCF_Err_Ok;
    FT_Memory  memory = FT_FACE(face)->memory;
    FT_Bool    hasBDFAccelerators;


    error = pcf_read_TOC( stream, face );
    if ( error )
      goto Exit;

    error = pcf_get_properties( stream, face );
    if ( error )
      goto Exit;

    /* Use the old accelerators if no BDF accelerators are in the file. */
    hasBDFAccelerators = pcf_has_table_type( face->toc.tables,
                                             face->toc.count,
                                             PCF_BDF_ACCELERATORS );
    if ( !hasBDFAccelerators )
    {
      error = pcf_get_accel( stream, face, PCF_ACCELERATORS );
      if ( error )
        goto Exit;
    }

    /* metrics */
    error = pcf_get_metrics( stream, face );
    if ( error )
      goto Exit;

    /* bitmaps */
    error = pcf_get_bitmaps( stream, face );
    if ( error )
      goto Exit;

    /* encodings */
    error = pcf_get_encodings( stream, face );
    if ( error )
      goto Exit;

    /* BDF style accelerators (i.e. bounds based on encoded glyphs) */
    if ( hasBDFAccelerators )
    {
      error = pcf_get_accel( stream, face, PCF_BDF_ACCELERATORS );
      if ( error )
        goto Exit;
    }

    /* XXX: TO DO: inkmetrics and glyph_names are missing */

    /* now construct the face object */
    {
      FT_Face       root = FT_FACE( face );
      PCF_Property  prop;


      root->num_faces  = 1;
      root->face_index = 0;
      root->face_flags = FT_FACE_FLAG_FIXED_SIZES |
                         FT_FACE_FLAG_HORIZONTAL  |
                         FT_FACE_FLAG_FAST_GLYPHS;

      if ( face->accel.constantWidth )
        root->face_flags |= FT_FACE_FLAG_FIXED_WIDTH;

      root->style_flags = 0;
      prop = pcf_find_property( face, "SLANT" );
      if ( prop != NULL )
        if ( prop->isString )
          if ( ( *(prop->value.atom) == 'O' ) ||
               ( *(prop->value.atom) == 'o' ) ||
               ( *(prop->value.atom) == 'I' ) ||
               ( *(prop->value.atom) == 'i' ) )
            root->style_flags |= FT_STYLE_FLAG_ITALIC;

      prop = pcf_find_property( face, "WEIGHT_NAME" );
      if ( prop != NULL )
        if ( prop->isString )
          if ( ( *(prop->value.atom) == 'B' ) ||
               ( *(prop->value.atom) == 'b' ) )
            root->style_flags |= FT_STYLE_FLAG_BOLD;

      root->style_name = (char *)"Regular";

      if ( root->style_flags & FT_STYLE_FLAG_BOLD ) {
        if ( root->style_flags & FT_STYLE_FLAG_ITALIC )
          root->style_name = (char *)"Bold Italic";
        else
          root->style_name = (char *)"Bold";
      }
      else if ( root->style_flags & FT_STYLE_FLAG_ITALIC )
        root->style_name = (char *)"Italic";

      prop = pcf_find_property( face, "FAMILY_NAME" );
      if ( prop != NULL )
      {
        if ( prop->isString )
        {
          int  l = ft_strlen( prop->value.atom ) + 1;


          if ( FT_NEW_ARRAY( root->family_name, l ) )
            goto Exit;
          ft_strcpy( root->family_name, prop->value.atom );
        }
      }
      else
        root->family_name = 0;

      /* Note: We shift all glyph indices by +1 since we must
       * respect the convention that glyph 0 always corresponds
       * to the "missing glyph".
       *
       * This implies bumping the number of "available" glyphs by 1.
       */
      root->num_glyphs = face->nmetrics + 1;

      root->num_fixed_sizes = 1;
      if ( FT_NEW_ARRAY( root->available_sizes, 1 ) )
        goto Exit;

      {
        FT_Bitmap_Size*  bsize = root->available_sizes;


        FT_MEM_ZERO( bsize, sizeof ( FT_Bitmap_Size ) );

        prop = pcf_find_property( face, "PIXEL_SIZE" );
        if ( prop != NULL )
          bsize->height = (FT_Short)prop->value.integer;

        prop = pcf_find_property( face, "AVERAGE_WIDTH" );
        if ( prop != NULL )
          bsize->width = (FT_Short)( ( prop->value.integer + 5 ) / 10 );

        prop = pcf_find_property( face, "POINT_SIZE" );
        if ( prop != NULL )
          /* convert from 722,7 decipoints to 72 points per inch */
          bsize->size =
            (FT_Pos)( ( prop->value.integer * 64 * 7200 + 36135L ) / 72270L );

        prop = pcf_find_property( face, "RESOLUTION_X" );
        if ( prop != NULL )
          bsize->x_ppem =
            (FT_Pos)( ( prop->value.integer * bsize->size + 36 ) / 72 );

        prop = pcf_find_property( face, "RESOLUTION_Y" );
        if ( prop != NULL )
          bsize->y_ppem =
            (FT_Pos)( ( prop->value.integer * bsize->size + 36 ) / 72 );

        if ( bsize->height == 0 )
          bsize->height = (FT_Short)( ( bsize->y_ppem + 32 ) / 64 );

        if ( bsize->height == 0 )
          bsize->height = 12;
      }

      /* set up charset */
      {
        PCF_Property  charset_registry = 0, charset_encoding = 0;


        charset_registry = pcf_find_property( face, "CHARSET_REGISTRY" );
        charset_encoding = pcf_find_property( face, "CHARSET_ENCODING" );

        if ( ( charset_registry != NULL ) &&
             ( charset_encoding != NULL ) )
        {
          if ( ( charset_registry->isString ) &&
               ( charset_encoding->isString ) )
          {
            if ( FT_NEW_ARRAY( face->charset_encoding,
                               ft_strlen( charset_encoding->value.atom ) + 1 ) )
              goto Exit;

            if ( FT_NEW_ARRAY( face->charset_registry,
                               ft_strlen( charset_registry->value.atom ) + 1 ) )
              goto Exit;

            ft_strcpy( face->charset_registry, charset_registry->value.atom );
            ft_strcpy( face->charset_encoding, charset_encoding->value.atom );
          }
        }
      }
    }

  Exit:
    if ( error )
    {
      /* this is done to respect the behaviour of the original */
      /* PCF font driver.                                      */
      error = PCF_Err_Invalid_File_Format;
    }

    return error;
  }


/* END */