Returns the "best" 3D polygonal line constructed on the points (xi, yi, zi)
(in the sense that consecutive points are as close as possible).
sort(p1) poi(g) axis(d) normal(n)
Returns the 3D polygonal line p1 sorted starting at its intersection with the axis (g, d)
and rotating in the positive direction around n.
1) g = center of gravity of p1 by default.
sort(p1) CG axis(d) normal(n); g = center of gravity of p1.
Returns the sort parameter of volume id.
Changes this parameter.
1) Si t=0: in a affcihage with transparency (see 'illum') facets will not be sorted:
calculations are thus accelerated, but the order of the facets must be opposite to that of their distances from the eye.
2) 1 is default, facets will be sorted.