POV-Ray : Newsgroups : povray.advanced-users : Adding forces to points in curves : Re: Adding forces to points in curves Server Time
30 Jul 2024 06:30:58 EDT (-0400)
  Re: Adding forces to points in curves  
From: Rune
Date: 28 Dec 1999 17:40:00
Message: <38693c40@news.povray.org>
Peter Popov wrote:
>this is an interesting approach. As far as I understand your problem
>is that when the points start repelling each other, they leave the
>spline, right?

Actually not. The idea was to use forces to change the spline so it would
get the right length, have more smooth bending, and to get equidistant
points.

However, I've now dropped this idea. Instead I want to calculate the spline
with the right length and then use your method to get equidistant points on
that spline. (See my reply to Mike Williams.)

>For every t
>there is an unique point on the spline. What you have to do is store
>an array of the values of t of the points on the spline. When you
>calculate the forces and the displacement they cause, apply this
>displacement along the t axis and not x,y or z. Then you'll know for
>sure that no whatever the points ditribution, the spline shape will
>remain constant.

I understand this.

However, I'm not sure what the difference is between this:

>Do this until no force is greater than a certain threshold value

...and this:

>or even better, the standard deviation of the forces
>falls below a certain level (i.e. the spline is equistressed).

But I guess that's not so important anyway. I get the basic idea.

Greetings,

Rune

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