"Tim Nikias" wrote:
> The problem is actually pretty simple.

> Think of the centrifugal-force when driving around a
> corner. That's what I want to calculate.

Assuming you have a spline function Spline(T) where T is the input
interpolation value, I think you can do it like this:

(Spline(T)-(Spline(T+0.001)+Spline(T-0.001))/2)

Some ASCII art to illsustrate the code:

          *****P*****
     *****           ******
   *A          C           B*
 **                          **
*                              *

P is Spline(T), A is Spline(T-0.001), B is Spline(T+0.001), C is the average
of A and B. Then you just find the vector from C to P.

Is this what you need, or did I understand you wrong?

Rune
--
3D images and anims, include files, tutorials and more:
Rune's World:    http://rsj.mobilixnet.dk (updated Feb 16)
POV-Ray Users:   http://rsj.mobilixnet.dk/povrayusers/
POV-Ray Webring: http://webring.povray.co.uk

Post a reply to this message