POV-Ray : Newsgroups : povray.beta-test.binaries : Re: RC4 quick summary of my reports - catmull-rom problem Server Time17 Sep 2024 10:40:08 EDT (-0400)
 Re: RC4 quick summary of my reports - catmull-rom problem (Message 1 to 1 of 1)
 From: Subject: Re: RC4 quick summary of my reports - catmull-rom problem Date: 10 May 2002 06:21:14 Message:
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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
```

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