"Mike the Elder" <nomail@nomail> wrote:
> I think you need to specify where the returned value is to be stored:> ...
On http://www.povray.org/documentation/view/3.6.1/243/ , it gives the example
#macro Interpolate(T,T1,T2,P1,P2)
(P1+(T1+T/(T2-T1))*(P2-P1))
#end
Which essentially replaces Interpolate(T,T1,T2,P1,P2) with
(P1+(T1+T/(T2-T1))*(P2-P1)).
