function IEVEN(real) c returns the nearest even integer to the given real number. c c This function is designed purely for use with GIGI graphics, and c accordingly assumes that the given real number is positive, c corresponding to a position on the screen. c half=real/2.0 ihalf=half frac=half-ihalf if (frac.ge.0.5) ihalf=ihalf+1 ieven=2*ihalf end