[ODE] Jitters

Tim Rightnour root at garbled.net
Mon Nov 8 17:14:18 MST 2004

On 08-Nov-2004 Geoff Carlton wrote:
> What is the mass?  If its very small then even 0.01x the velocity can be 
> too great a force (I've seen this with very small objects).  Try a lower 
> value for both linear and angular, and see if it fixes it, (e.g. -0.001).
> Judging by the results it looks like the -0.01 is providing way too much 
> force and the object is flying in the opposite direction each frame.

Looks like you were dead on.  I guess I forgot that I was applying force
directly to the object, not just modifying it's linear velocity directly.  My
masses are all rather minute, due to me trying to keep them between 0 and 10. 
It means my light objects all have infitesimally small masses because they got
normalized against things like houses and churches.

I still can't make the jitters go away, but perhaps if I play with the damping
forces some more, I can find a value that magically works.

Stupid me.  My old physics code just had me working directly with linear
velocity, not applying force, I guess I got it confused in my head.  Thanks to
everyone for helping me find where I went wrong with the damping.

Tim Rightnour <root at garbled.net>
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