[ODE] Do you have to use constant time steps?

Roel van Dijk roelvandijk at home.nl
Fri Jun 20 00:51:02 2003


I'm using the frame time to step the world and I'm using stepfast. I can't say 
that I have any noticable problems. Only when the fps gets realy low (like < 
5) objects can go underground. But that's normal I think because at 5 fps the 
timestep is very large.
You could ofcourse as Adam D. Moss mentioned create a system to regulate the 
fps. Maybe you can set a minimum fps for the physics and if fps gets below 
that limit render less frames (so there is more cpu time for the physics).

> In the examples, the time step is set to 0.05 -- a constant value. Is this
> important? I really hope not, as I want to just use the time taken to
> render the last frame; this way physics are not dependent on framerate.
> With a constant value, things will happen faster if the framerate is high.
> I can't think why the time step would need to be constant but I know
> sometimes people's physics routines require it to be.
>
> Since framerate is variable the time step would then be variable, by the
> way. It could be 0.05 one frame and 0.02 the next.