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Wasn't it Ken who wrote:
>
>
>Nekar Xenos wrote:
>
>> Ok, so what's the isosurface formula for each of these? =)
>
>Parametric:
>
> This short note describes the parametric equations which give
> rise to an approximate model of a drop of water, for example, a
> tear drop.
>
> The equations as functions of longitute phi and lattitude theta are:
>
> x = 0.5 *(1-cos(8)) sin(8) cos(circle with verticle line through it)
> y = 0.5 *(1-cos(8)) sin(8) sin(circle with verticle line through it)
> z = cos(8)
>
> where 0 <= circ w/line tru/it <= 2pi
> and 0 <= 8 <= pi
For those of you who prefer stuff in POV language:-
#version 3.5;
camera { location <0, 0, -2.4> look_at 0}
light_source {<100,100,-100> colour rgb 1}
#declare Fx = function(u,v) {0.5 *(1-cos(u)) *sin(u) *cos(v)}
#declare Fz = function(u,v) {0.5 *(1-cos(u)) *sin(u) *sin(v)}
#declare Fy = function(u,v) {cos(u)}
#declare Umin = 0;
#declare Umax = pi;
#declare Vmin = 0;
#declare Vmax = 2*pi;
#declare Iter_U = 50;
#declare Iter_V = 50;
#include "param.inc"
Parametric()
object {Surface
pigment {rgb 0.9}
}
I've used Ingo's "param.inc" because when I tried it as a real
parametric isosurface the "pixels per hour" figure looked like it was
heading for zero. I've switched the z and y values so that the pointy
bit is at the top.
--
Mike Williams
Gentleman of Leisure
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