[osg-users] osgUtil::IntersectionVisitor, information on polygon intersected
jean-sebastien.guay at cm-labs.com
Wed Sep 17 13:28:49 PDT 2008
Thanks for confirming my hunch about the ratioList. I've never used that
functionality but I've been around the LineSegmentIntersector code a bit
and I remembered it being something like that, but wasn't sure.
>> If that's the case, you can
>> do the same with the triangle's texture coordinates at the 3 same
>> vertices and thus get where in the texture the hit occured.
> I'm not sure about this one, but it should give a reasonable approximation
> anyway :)
You're right, there might be some other things like perspective
correction that enter into the equation. I'd have to research the actual
equations that OpenGL uses to calculate a texture coordinate based on
the triangle's 3 vertices' texture coordinates in order to sample the
texture at the right texel. It's probably well documented, but it's not
the kind of thing I tend to memorize...
Anyways, I think we're going a bit further than what the OP asked. :-)
Jean-Sebastien Guay jean-sebastien.guay at cm-labs.com
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