From: David Fontaine
Subject: WAAH! Math help please!!!!!
Date: 19 Dec 1999 15:15:39
Message: <385D3AF4.827CE694@isd.net>
I need a shape formed by sweeping an arc around the axis going through
it's endpoints, in *standard* POV. With an isosurface, I can use the
torus equation (sqrt(x^2+z^2)+Major)^2+y^2-Minor^2=0, but when I expand
this to a quartic for normal POV it's a full torus instead of just the
arc sweep. See my post in p.b.i for the pics of the two different
methods.
--
http://thunder.prohosting.com/~davidf/
___ ______________________________
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From: Gerald K Dobiasovsky
Subject: Re: WAAH! Math help please!!!!!
Date: 19 Dec 1999 16:39:06
Message: <385d507a@news.povray.org>
"David Fontaine" <lfo### [at] isdnet> wrote:
> I need a shape formed by sweeping an arc around the axis going
through
> it's endpoints, in *standard* POV. With an isosurface, I can use the> torus equation (sqrt(x^2+z^2)+Major)^2+y^2-Minor^2=0, but when I
expand
> this to a quartic for normal POV it's a full torus instead of just
the
> arc sweep. See my post in p.b.i for the pics of the two different> methods.
This is a "spindle torus" and you want only the spindle.
Use "intersection" or "clipped_by" with an object that slices of
the rest (i.e. a sphere which has the distance between those arc
endpoints as diameter).
--
Gerald
ger### [at] aonat
From: David Fontaine
Subject: Re: WAAH! Math help please!!!!!
Date: 19 Dec 1999 18:17:33
Message: <385D656E.489015D9@isd.net>
Thanks! Interseting fixes a small problem I was gaving with bounded_by and
clipped_by.
--
http://thunder.prohosting.com/~davidf/
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