ttload.c

神龙卡开发原代码

 *  Input  :  face
 *
 *  Output :  Error code.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_CMap( PFace  face )
  {
    DEFINE_LOCALS;

    Long  off, table_start;
    Long  n, limit;

    TCMapDir       cmap_dir;
    TCMapDirEntry  entry_;
    PCMapTable     cmap;


    PTRACE2(( "CMaps " ));

    if ( ( n = TT_LookUp_Table( face, TTAG_cmap ) ) < 0 )
      return TT_Err_CMap_Table_Missing;

    table_start = face->dirTables[n].Offset;

    if ( ( FILE_Seek( table_start ) ) ||
         ( ACCESS_Frame( 4L ) ) )           /* 4 bytes cmap header */
      return error;

    cmap_dir.tableVersionNumber = GET_UShort();
    cmap_dir.numCMaps           = GET_UShort();

    FORGET_Frame();

    off = FILE_Pos();  /* save offset to cmapdir[] which follows */

    /* save space in face table for cmap tables */
    if ( ALLOC_ARRAY( face->cMaps,
                      cmap_dir.numCMaps,
                      TCMapTable ) )
      return error;

    face->numCMaps = cmap_dir.numCMaps;

    limit = face->numCMaps;
    cmap  = face->cMaps;

    for ( n = 0; n < limit; n++ )
    {
      if ( FILE_Seek( off )  ||
           ACCESS_Frame( 8L ) )
        return error;

      /* extra code using entry_ for platxxx could be cleaned up later */
      cmap->loaded             = FALSE;
      cmap->platformID         = entry_.platformID         = GET_UShort();
      cmap->platformEncodingID = entry_.platformEncodingID = GET_UShort();

      entry_.offset = GET_Long();

      FORGET_Frame();

      off = FILE_Pos();

      if ( FILE_Seek( table_start + entry_.offset ) ||
           ACCESS_Frame( 6L ) )
        return error;

      cmap->format  = GET_UShort();
      cmap->length  = GET_UShort();
      cmap->version = GET_UShort();

      FORGET_Frame();

      cmap->offset = FILE_Pos();

      cmap++;
    }

    PTRACE2(( "loaded\n" ));

    return TT_Err_Ok;
  }


/*******************************************************************
 *
 *  Function    :  Load_TrueType_Programs
 *
 *  Description :  Loads the font (fpgm) and cvt programs into the
 *                 face table.
 *
 *  Input  :  face
 *
 *  Output :  Error code.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_Programs( PFace  face )
  {
    DEFINE_LOCALS_WO_FRAME;

    Long  n;


    PTRACE2(( "Font program " ));

    /* The font program is optional */
    if ( ( n = TT_LookUp_Table( face, TTAG_fpgm ) ) < 0 )
    {
      face->fontProgram = NULL;
      face->fontPgmSize = 0;

      PTRACE2(( "is missing!\n" ));
    }
    else
    {
      face->fontPgmSize = face->dirTables[n].Length;

      if ( ALLOC( face->fontProgram,
                  face->fontPgmSize )              ||
           FILE_Read_At( face->dirTables[n].Offset,
                         (void*)face->fontProgram,
                         face->fontPgmSize )       )
        return error;

      PTRACE2(( "loaded, %12d bytes\n", face->fontPgmSize ));
    }

    PTRACE2(( "Prep program " ));

    if ( ( n = TT_LookUp_Table( face, TTAG_prep ) ) < 0 )
    {
      face->cvtProgram = NULL;
      face->cvtPgmSize = 0;

      PTRACE2(( "is missing!\n" ));
    }
    else
    {
      face->cvtPgmSize = face->dirTables[n].Length;

      if ( ALLOC( face->cvtProgram,
                  face->cvtPgmSize )               ||
           FILE_Read_At( face->dirTables[n].Offset,
                         (void*)face->cvtProgram,
                         face->cvtPgmSize )        )
        return error;

      PTRACE2(( "loaded, %12d bytes\n", face->cvtPgmSize ));
    }

    return TT_Err_Ok;
  }


/*******************************************************************
 *
 *  Function    :  Load_TrueType_OS2
 *
 *  Description :  Loads the OS2 Table.
 *
 *  Input  :  face
 *
 *  Output :  Error code.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_OS2( PFace  face )
  {
    DEFINE_LOCALS;

    Long     i;
    TT_OS2*  os2;


    PTRACE2(( "OS/2 Table " ));

    /* We now support old Mac fonts where the OS/2 table doesn't  */
    /* exist.  Simply put, we set the `version' field to 0xFFFF   */
    /* and test this value each time we need to access the table. */
    if ( ( i = TT_LookUp_Table( face, TTAG_OS2 ) ) < 0 )
    {
      PTRACE2(( "is missing\n!" ));
      face->os2.version = 0xFFFF;
      error = TT_Err_Ok;
      return TT_Err_Ok;
    }

    if ( FILE_Seek( face->dirTables[i].Offset ) ||
         ACCESS_Frame( 78L ) )
      return error;

    os2 = &face->os2;

    os2->version             = GET_UShort();
    os2->xAvgCharWidth       = GET_Short();
    os2->usWeightClass       = GET_UShort();
    os2->usWidthClass        = GET_UShort();
    os2->fsType              = GET_Short();
    os2->ySubscriptXSize     = GET_Short();
    os2->ySubscriptYSize     = GET_Short();
    os2->ySubscriptXOffset   = GET_Short();
    os2->ySubscriptYOffset   = GET_Short();
    os2->ySuperscriptXSize   = GET_Short();
    os2->ySuperscriptYSize   = GET_Short();
    os2->ySuperscriptXOffset = GET_Short();
    os2->ySuperscriptYOffset = GET_Short();
    os2->yStrikeoutSize      = GET_Short();
    os2->yStrikeoutPosition  = GET_Short();
    os2->sFamilyClass        = GET_Short();

    for ( i = 0; i < 10; i++ )
      os2->panose[i] = GET_Byte();

    os2->ulUnicodeRange1     = GET_ULong();
    os2->ulUnicodeRange2     = GET_ULong();
    os2->ulUnicodeRange3     = GET_ULong();
    os2->ulUnicodeRange4     = GET_ULong();

    for ( i = 0; i < 4; i++ )
      os2->achVendID[i] = GET_Byte();

    os2->fsSelection         = GET_UShort();
    os2->usFirstCharIndex    = GET_UShort();
    os2->usLastCharIndex     = GET_UShort();
    os2->sTypoAscender       = GET_Short();
    os2->sTypoDescender      = GET_Short();
    os2->sTypoLineGap        = GET_Short();
    os2->usWinAscent         = GET_UShort();
    os2->usWinDescent        = GET_UShort();

    FORGET_Frame();

    if ( os2->version >= 0x0001 )
    {
      /* only version 1 tables */

      if ( ACCESS_Frame( 8L ) )  /* read into frame */
        return error;

      os2->ulCodePageRange1 = GET_ULong();
      os2->ulCodePageRange2 = GET_ULong();

      FORGET_Frame();
    }
    else
    {
      os2->ulCodePageRange1 = 0;
      os2->ulCodePageRange2 = 0;
    }

    PTRACE2(( "loaded\n" ));

    return TT_Err_Ok;
  }


/*******************************************************************
 *
 *  Function    :  Load_TrueType_PostScript
 *
 *  Description :  Loads the post table into face table.
 *
 *  Input  :  face         face table to look for
 *
 *  Output :  SUCCESS on success.  FAILURE on error.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_PostScript( PFace  face )
  {
    DEFINE_LOCALS;

    Long  i;

    TT_Postscript*  post = &face->postscript;


    PTRACE2(( "PostScript " ));

    if ( ( i = TT_LookUp_Table( face, TTAG_post ) ) < 0 )
      return TT_Err_Post_Table_Missing;

    if ( FILE_Seek( face->dirTables[i].Offset ) ||
         ACCESS_Frame( 32L ) )
      return error;

    /* read frame data into face table */

    post->FormatType         = GET_ULong();
    post->italicAngle        = GET_ULong();
    post->underlinePosition  = GET_Short();
    post->underlineThickness = GET_Short();
    post->isFixedPitch       = GET_ULong();
    post->minMemType42       = GET_ULong();
    post->maxMemType42       = GET_ULong();
    post->minMemType1        = GET_ULong();
    post->maxMemType1        = GET_ULong();

    FORGET_Frame();

    /* we don't load the glyph names, we do that in a */
    /* library extension (ftxpost).                   */

    PTRACE2(( "loaded\n" ));

    return TT_Err_Ok;
  }


/*******************************************************************
 *
 *  Function    :  Load_TrueType_Hdmx
 *
 *  Description :  Loads the horizontal device metrics table.
 *
 *  Input  :  face         face object to look for
 *
 *  Output :  SUCCESS on success.  FAILURE on error.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_Hdmx( PFace  face )
  {
    DEFINE_LOCALS;

    TT_Hdmx_Record*  rec;
    TT_Hdmx          hdmx;
    Long             table;
    UShort           n, num_glyphs;
    Long             record_size;


    hdmx.version     = 0;
    hdmx.num_records = 0;
    hdmx.records     = 0;

    face->hdmx = hdmx;

    if ( ( table = TT_LookUp_Table( face, TTAG_hdmx ) ) < 0 )
      return TT_Err_Ok;

    if ( FILE_Seek( face->dirTables[table].Offset )  ||
         ACCESS_Frame( 8L ) )
      return error;

    hdmx.version     = GET_UShort();
    hdmx.num_records = GET_Short();
    record_size      = GET_Long();

    FORGET_Frame();

    /* Only recognize format 0 */

    if ( hdmx.version != 0 )
      return TT_Err_Ok;

    if ( ALLOC( hdmx.records, sizeof ( TT_Hdmx_Record ) * hdmx.num_records ) )
      return error;

    num_glyphs   = face->numGlyphs;
    record_size -= num_glyphs+2;
    rec          = hdmx.records;

    for ( n = 0; n < hdmx.num_records; n++ )
    {
      /* read record */

      if ( ACCESS_Frame( 2L ) )
        goto Fail;

      rec->ppem      = GET_Byte();
      rec->max_width = GET_Byte();

      FORGET_Frame();

      if ( ALLOC( rec->widths, num_glyphs )  ||
           FILE_Read( rec->widths, num_glyphs ) )
        goto Fail;

      /* skip padding bytes */
      if ( record_size > 0 )
        if ( FILE_Skip( record_size ) )
          goto Fail;

      rec++;
    }

    face->hdmx = hdmx;

    return TT_Err_Ok;

  Fail:
    for ( n = 0; n < hdmx.num_records; n++ )
      FREE( hdmx.records[n].widths );

    FREE( hdmx.records );
    return error;
  }


/*******************************************************************
 *
 *  Function    :  Free_TrueType_Hdmx
 *
 *  Description :  Frees the horizontal device metrics table.
 *
 *  Input  :  face         face object to look for
 *
 *  Output :  TT_Err_Ok.
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Free_TrueType_Hdmx( PFace  face )
  {
    UShort  n;


    if ( !face )
      return TT_Err_Ok;

    for ( n = 0; n < face->hdmx.num_records; n++ )
      FREE( face->hdmx.records[n].widths );

    FREE( face->hdmx.records );
    face->hdmx.num_records = 0;

    return TT_Err_Ok;
  }


/*******************************************************************
 *
 *  Function    :  Load_TrueType_Any
 *
 *  Description :  Loads any font table into client memory. Used by
 *                 the TT_Get_Font_Data() API function.
 *
 *  Input  :  face     face object to look for
 *
 *            tag      tag of table to load. Use the value 0 if you
 *                     want to access the whole font file, else set
 *                     this parameter to a valid TrueType table tag
 *                     that you can forge with the MAKE_TT_TAG
 *                     macro.
 *
 *            offset   starting offset in the table (or the file
 *                     if tag == 0 )
 *
 *            buffer   address of target buffer
 *
 *            length   address of decision variable :
 *
 *                       if length == NULL :
 *                             load the whole table. returns an
 *                             an error if 'offset' == 0 !!
 *
 *                       if *length == 0 :
 *                             exit immediately, returning the
 *                             length of the given table, or of
 *                             the font file, depending on the
 *                             value of 'tag'
 *
 *                       if *length != 0 :
 *                             load the next 'length' bytes of
 *                             table or font, starting at offset
 *                             'offset' (in table or font too).
 *
 *  Output :  Error condition
 *
 ******************************************************************/

  LOCAL_FUNC
  TT_Error  Load_TrueType_Any( PFace  face,
                               ULong  tag,
                               Long   offset,
                               void*  buffer,
                               Long*  length )
  {
    TT_Stream  stream;
    TT_Error   error;
    Long       table;
    ULong      size;


    if ( tag != 0 )
    {
      /* look for tag in font directory */
      table = TT_LookUp_Table( face, tag );
      if ( table < 0 )
        return TT_Err_Table_Missing;

      offset += face->dirTables[table].Offset;
      size    = face->dirTables[table].Length;
    }
    else
      /* tag = 0 -- the use want to access the font file directly */
      size = TT_Stream_Size( face->stream );

    if ( length && *length == 0 )
    {
      *length = size;
      return TT_Err_Ok;
    }

    if ( length )
      size = *length;

    if ( !USE_Stream( face->stream, stream ) )
      (void)FILE_Read_At( offset, buffer, size );
    DONE_Stream( stream );

    return error;
  }


/* END */