On Fri, 10 May 2002 01:36:17 +0200, Tor Olav Kristensen
<tor### [at] hotmailcom> wrote:
> Just differentiate these (to quadratic polynomials) and
> solve for zero to find the max and min points of the
> cubic polynomials. The values of the cubic polynomials
> at these points will give the components for the
> bounding box.
Sounds reasonably and attachement shows it is easy possible (considering I
used proper equation for catmull-rom spline). Of course equations could be
simpler internally becouse it is just solution of quadratic polynomial.
Solution represents t value where p has extremas. When t is outside [0,1]
range then take p1 or p2 otherwise calculate p(t). Add Proper radius to
calculated value. I have no easy access to the C compiler for prepare
corrected MegaPOV function but perhaps somebody could hardcode this.
ABX
Post a reply to this message
Attachments:
Download 'catmull-rom.png' (8 KB)
Preview of image 'catmull-rom.png'
|