code: public static double[] getTileLayerSize(TileCode code, Envelope maxExtent, double scale) {
  		double div = Math.pow(2, code.getTileLevel());
  		double tileWidth = Math.ceil((scale * maxExtent.getWidth()) / div) / scale;
  		double tileHeight = Math.ceil((scale * maxExtent.getHeight()) / div) / scale;
  		return new double[] { tileWidth, tileHeight };
  	}
docs: Calculates the tiles width and height.
  
  @param code
  The unique tile code. Determines what tile we're talking about.
  @param maxExtent
  The maximum extent of the grid to which this tile belongs.
  @param scale
  The current client side scale.
  @return Returns an array of double values where the first value is the tile width and the second value is the
  tile height.