[ODE] cylinder woes

Riley Lark rileylark at gmail.com
Fri Dec 1 19:06:43 MST 2006


First of all, I am using the latest update from the SVN server.  I am
attempting to collide cylinders against boxes in my project, and
hitting a very frustrating problem that I've been hacking at for the
last several hours.  The cylinder test apps packaged with ode work
perfectly, and yet when I try to use them in my project, I get odd
behavior and eventually crash on an assert on line 333 of
collision_util.h .

The odd behavior: The cylinder seems to be longer than it should.
That is, the edge of the cylinder extends approximately 50% again past
the edge of my graphical representation.

The crash: the crash only happens when a flat end of the cylinder is
about to land more-or-less flat on the box.  When the cylinder lands
mostly with the curved side along the box, it bounces around for a
while and looks completely normal, and then comes to a rest, maybe
rolling a bit.  When the cylinder lands mostly on end, the app crashes
before the collision ever occurs.  You can see a screenshot of the
crash at http://files.larkolicio.us/modball/images/cylinder_error.jpg

I am at a loss.  I am fairly sure that I am doing everything I should
need to initialize the cylinder.  When I try replacing the
dCreateCylinder call with a dCreateSphere call, everything works
perfectly (with a sphere), so I think I am not forgetting anything.

I know this is an extremely vague problem but my hope is that someone
has some idea about where I can look next for the error.  Again, the
identical ode binaries used with the test_cyl projects lead to 100%
correct-looking results, even when I set up the examples to land the
cylinders on their ends.

Thanks for any ideas~


PS: please let me know if this mailing list is only for development of
ODE and not for help getting it working.  I don't want to misuse it.

More information about the ODE mailing list