Christopher James Huff wrote:

> In article <3f36803d@news.povray.org>, Wolfgang Wieser <wwi### [at] gmxde>
> wrote:
> 
>> Wouldn't it be easier to use a lathe with _quadratic_
>> spline for the parabolic mirror?
> 
> The easiest way would be to use an isosurface, a quadric is probably the
> most efficient way. I wouldn't use a lathe, though it would work.
> 
A paraboloid is essentially y=x^2 rotated around the Y axis (isn't it??)
So, using a quadratic spline and modelling just that y=x^2 curve 
seems to me the most natural approach to me. 

Why should I use a quadric? Is it really faster than a lathe?

Wolfgang

Post a reply to this message