[ODE] Using rays to generate a light/shadow map
hplus-ode at mindcontrol.org
Wed Nov 3 08:54:00 MST 2004
> surface( 791.01, 4990.24, 0.57 ) <-- ray origin
Are you using floats or doubles? Values of magnitude 5000
don't have all that much useable precision in floats -- only
about 1e-3 at that point.
> Anyway, I know there's nothing for the ray to collide with. Also, I'm
> projecting the ray's origin away from the triangle center along the
There's the actual triangle surface. It's quite possible that
the ray collides with the base surface because of numerical
> So, I'm thinking that even though I'm manually calling dCollide with my
> ray and with the terrain geom, perhaps there's some magic that needs
> doing by calling dWorldStep at least once?
That seems unlikely.
I would pick a single, representative spot, and run the collision
from there (possibly using "manual code" right before the automated
ray cast). Then examine what you're actually colliding with inside
the collision callback. Maybe use the ability to extract the collided
triangle from the mesh, too.
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