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Subject: Re: Intersection of a plane and finite line segment in 3D space
Date: Mon, 4 Apr 2011 08:16:04 +0000 (UTC)
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Thanks, Rune. Another solution could be the following: 1) check if the ray intersects the triangle, and 2) in case of intersection, check if the intersection point belongs to the line segment defined by two points in 3D.

Rune Allnor <allnor@tele.ntnu.no> wrote in message <70a9d01e-e1bb-47da-83f6-5dc20ab2d44a@dr5g2000vbb.googlegroups.com>...
> On Apr 4, 8:54 am, "Liana " <liananapalk...@email.arizona.edu> wrote:
> > I'm sorry, I should paraphrase my question. What I'm searching is the intersection of the line segment and the triangle (not tetrahedron) in 3D space. I think that's the reason why I get incorrect results. In fact, the triangle belongs to the plane, but it is just a fragment of that plane.
>
> 1) Find the intersection point p between the line L and
>    the plane P, if such a point exists
> 2) Determine if p belongs to the finite section of L
> 3) Determine if p is located in the interior of the
>    triangle T, given by the points (q,r,s).
>
> Rune
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