[ODE] Is ODE a deterministic physic engine ?

Klaus Backert Klaus.Backert at t-online.de
Mon Dec 11 10:46:47 MST 2006


Am 11.12.2006 um 12:51 schrieb Yanuar Tanzil:

> Hi, I just found out that ODE isn't deterministic physic simulator! I
> ran a simulation of two identical solids dropped from an identical
> height to an identical plane, the result (bounce) is different between
> two solids.
> Is there a way to make it deterministic ? shouldn't those two solids
> simulate the same way ?

Some parts of ODE use pseudo random numbers. If I remember correctly  
it's in collision detection, and it's there in order to improve the  
stability (?) of the algorithm.

Be sure to reset the random number seed before starting a simulation.

(BTW: this has been discussed on this list some time ago)

Cheers
Klaus



More information about the ODE mailing list