[ODE] ODE 0.50 distribution

[Ed Jones]

FYI; I've also experienced problems with the latest (0.5 release, single 
precision, msvc-dll) version of ODE when colliding CCylinders with 
Trimeshes.
Boxes and Spheres work perfectly. Capped cylinders seem to go about 
halfway through the mesh then either slowly sink through the rest of the 
way or explode in random directions, depending on whether I set a 
maximum correction velocity or not.

I've tried tweaking the gravity, the mass, the size of the triangle in 
the mesh, using step v.s quickStep. But nothing seems to make a 
difference. The boxes and spheres still work and the ccylinders don't! 
Everything else works just fine, and ccylinders collide with other 
things (including planes) perfectly.

For eye-candy purposes only, there's a picture of the spheres and boxes 
working correctly (obviously I didn't show the capsules not working!) here;
http://www.ogre3d.org/phpBB2/viewtopic.php?t=4696&start=39


John Miles wrote:

>Basically, I have a trimesh terrain that consists of a lot of small
>triangles lying in (in this case) a flat plane.  If an object represented by
>a relatively-large OBB falls onto the terrain, it tends to sink into the
>terrain, sometimes stopping around the halfway point, and other times
>falling on through.
>
>You can see an example of this halfway-point sinkage at
>http://thegleam.com/test.jpg .  The bottom half of the bow's OBB is below
>the trimesh terrain.
>
>With Erwin's code, it behaves fine.  The objects land on the terrain and
>settle down rapidly, especially with the new QuickStep solver enabled.
>
>I don't use CCylinder-TriMesh collisions for anything except kinematic
>collisions (where I reverse the collision penetration manually to move the
>user-controlled object back, without generating any contacts).  This was
>pretty heavily-tweaked for use with Erwin's collider, so it's not surprising
>that it doesn't work well with the new one without a similar amount of
>tweaking and contact-filtering.
>
>Again, if I'm the only one who's noticing this, it's most likely some
>artifact of my own implementation.  It works fine when the engine is built
>with either Erwin's OBB-TriMesh collider or the Novodex library... just not
>with the Croteam collider.
>
>I wouldn't sweat it unless others report similar misbehavior.  That's why I
>posted the description of the problem -- to see if it's happening to anyone
>else.
>
>-- jm
>
>  
>
>>    That's very strange men!
>>    In my side, Croteam code works very well and I think it's much better
>>    than Erwin's. For example, in the case capped cylinder vs trimesh,
>>    Erwin's code only generate ONE collision point (which is
>>    absolutely not right). Could you please point out the case you
>>    found Croteam's code fail?
>>
>>    
>>
>
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