size 400 400 set mapsize 400 paper 10 20 30 number mod x y { value (x-(y*(x/y))) }
set rseed number random x { set r1 (rseed*435437) set r2 (rseed+945878) set rseed value } command mirror x y { set color set [x y] color set temp (mapsize-x) set [temp y] color set temp (mapsize-y) set [x temp] color set temp (mapsize-x) set tempx (mapsize-y) set [temp tempx] color } set startx 0 set starty 0 forever { same? 100 { mirror } }