[PD] Find distance to a line in 3d space

[Ba Prince]

Hi

  If you want to know the distance between a point and line in 3D space :

1 - you calculate the vector director (= vecteur directeur ?) u-> of the
line
2 - you select any point A from your line
3 - you calculate the vector AB->
4 - you calculate || (AB->) ^ (u->) || / || u-> || , with  || . ||
euclidian norm and ^ cross product

the distance is d =  || (AB->) ^ (u->) || / || u-> ||

Prince




2013/12/26 Max <abonnements at revolwear.com>

> Hi João,
> I patched something for you, maybe it's useful.
>
>
>
>
> http://mathsfirst.massey.ac.nz/Algebra/PythagorasTheorem/pythapp.htm
>
>
> Am 11.12.2013 um 02:30 schrieb João Pais <jmmmpais at googlemail.com>:
>
> > Am 06.12.2013, 00:51 Uhr, schrieb Claude Heiland-Allen <
> claude at mathr.co.uk>:
> >
> >> On 05/12/13 23:40, João Pais wrote:
> >>> Hello list,
> >>>
> >>> I had a doubt, will try to explain.
> >>>
> >>> I wanted to define a line in a 3d space through 2 points, and be able
> to
> >>> find out the distance from another point to that line. Since I'm very
> >>> bad at math, I wanted to know if anyone has done something similar, or
> >>> knows how to get to it.
> >>
> >> http://paulbourke.net/geometry/pointlineplane/
> >>
> >> first example on the page, you just need to clamp u to [0..1] if you
> >> want to make it work for a line segment instead of an infinite line.
> >
> > it looks interesting, and I also checked for more content with a similar
> title. the thing is, my math/geometry skills are too bad, and I don't
> understand where they get the formulas for the points and lines. I'll keep
> watching the links, but I might not get it in time for the purpose I was
> looking for.
> >
> > thanks anyway,
> >
> > João
> >
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