How to check if a point is within a triangle....

jollyjeffers · 2001-10-24T17:40:06

Hi, I''ve been using the standard plane-ray intersection test to do some simple ray-tracing... but I now need to know if a given point-of-intersection is actually in the triangle... I know that the point is on the surface of the triangle, I need to know if it''s within the boundaries... I have: • the 3 vertices making up the triangle (in 3D space) • the collision point (in 3D space) • the plane coefficients/normal etc... I''ve got a feeling I''ll need "barycentric" coordinates - but I dont know how to use the formula/algorithm... could someone tell me how to sort this out?? many thanks, Jack;

Math and Physics Programming

Started by jollyjeffers October 24, 2001 09:12 AM

9 comments, last by jollyjeffers 23 years, 3 months ago

jollyjeffers

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October 24, 2001 05:40 PM

hey thanks people.... some interesting solutions; I intend to document the final code that I use, and I''ll include your ideas (I''d never thought of dividing into 3 triangles)...

I finally solved my problem using some sort of barycentric coordinate system... and it seems to work pretty welll.

Jack;

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