fill a rectangle
xfrect(x,y,w,h) xfrect(rect) // rect =[x,y,w,h]
four real values defining the rectangle.
xrect fills a rectangle defined by [x,y,w,h] (upper-left point, width, height) in user coordinates.
xrect
[x,y,w,h]
plot2d(0,0,-1,"010"," ",[-2,-2,2,2]) xfrect(-1,1,2,2) gce().background = color("green");