Attempt at a 3D parametric grapher

[Han]

That snippet of code was supposed to draw a 3D path defined by r(t) -- basically a helix. The a represents the radius of the helix, c its height, and t0 and tn are the starting/ending angles of the helix.

If you want to create a 3D parametric grapher, you will need to generate your points, and use the TRIANGLE or TRIANGLE_P command. Read

http://www.hpmuseum.org/forum/thread-5122.html

for a brief overview.