private long calcFilePosition( int column, int row ) { long tileId = getTileId( column, row ); // System.out.println( "row: " + row + ", col: " + column + " is tile in file: " + tileId ); long tileInBlob = tileId % tilesInFile; // System.out.println( "tile in blob: " + tileInBlob ); return tileInBlob * bytesPerTile; }