### Clipping

pm3d clipping with respect to x, y coordinates of quadrangles can be done two ways. clip1in: all 4 points of each quadrangle must be defined and at least 1 point of the quadrangle must lie in the x and y ranges. clip4in: all 4 points of each quadrangle must lie in the x and y ranges.

clipcb (default): palette color values are clipped to cbmin and cbmax. noclipcb: quadrangles with palette color value outside of the current cbrange are not drawn at all.