I have a parametric surface plot defined as

splot [u = 0:1] [v = 0:1] Fx(u,v), Fy(u,v), Fz(u,v) with pm3d

This plots a nice picture where surface areas with a high value for z have a bright color, and for low values of z a dark color. Now I would like to link the color of the surface based on my own function. For instance this could be the curvature of the surface. This is when I define the following function

C(u,v) = ...

then need for the surface area located at Fx(u,v), Fy(u,v), Fz(u,v) the color C(u,v).

If this is possible, could somebody explain to me how to do it?

Best regards,

Björn