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C++
12-06-2002, 11:02 AM
Please, help me understand, how to detect: lies the point in triangle or not? I know, that this algorithm called as "barycentric" ("barycentric intersection"). As answer, give me a very small example please (more precisely, part of this example, when we detecting the point position) and just small math information.

If this topic had never been in this forum, I think it would be interesting.

P.S.
Please, don`t give me a useless answers or references.

Kilam Malik
12-06-2002, 01:50 PM
Goto "search" in this forum and try

triangle intersection (46 hits)
or
bary (10 hits)


BTW: This question is not interesting.

Kilam.

V-man
12-06-2002, 06:15 PM
What do you mean by give me an example? There are many examples that do intersection tests. Download some 3D games like Quake.

If you need code, then try the magicsoftware web site. They have a huge library adn examples using them.

PS: your question is not about raytracing

V-man

Humus
12-07-2002, 03:33 AM
The point is in the polygon plane?
Then, if the point is behind all edge planes (or in front depending how you turn the normals) then it's in the polygon. The edge planes are easy to calculate with two vertices and the polygon normal.

Maj
12-07-2002, 08:01 AM
You might find the first article here (http://www.acm.org/tog/resources/RTNews/html/rtnv5n3.html#contents) useful.

*Aaron*
12-07-2002, 01:44 PM
I think this (http://www.disney.com) is more his level.

Julien Cayzac
12-08-2002, 06:34 AM
Originally posted by *Aaron*:
I think this (http://www.disney.com) is more his level.

Woah ! That toon shader is impressive ! Where can I get the CG source code? http://www.opengl.org/discussion_boards/ubb/biggrin.gif http://www.opengl.org/discussion_boards/ubb/biggrin.gif

Julien