[ODE] dBodyGetForce returns zero force

[Gazi Alankus]

I'm attaching my patch that adds dBodyGetPrevForce() and
dBodyGetPrevTorque(), also dBody::getPrevForce() and
dBody::getPrevTorque() for the C++ interface. This is meant to be used
with ode-0.8 and lets you get the resultant force in the last step. So
things like gravity should be in the prevForce. I don't use quickstep
so I didn't do anything about it, if there is demand I can look into
what can be done there.

-Gazi


On 28/06/07, Patrick Enoch <Hendrix_ at gmx.net> wrote:
> Gravity is applied during the timestep-routine. So you do not "see" it.
>
> On 28.06.2007, at 11:03, PKS123 wrote:
>
> >
> > Hi
> >
> > I am using the dBodyGetForce() function to find out the force on a
> > body
> > which is in free fall.
> > The function is returning a zero vector.
> > I noticed from the ODE Documentation that the force accumulators
> > are set to
> > zero after each time step. So, I put the function both before and
> > after the
> > dWorldQuickStep() function but the value was zero in both cases.
> >
> > The Body has a mass of 100, and so the minimum force that I should be
> > getting is m*g ie. 100*9.8
> > But I get a zero force. Could anyone suggest what might be wrong.
> >
> > Thanks and Regards
> > PKS123
> > --
> > View this message in context: http://www.nabble.com/dBodyGetForce-
> > returns-zero-force-tf3993241.html#a11339547
> > Sent from the ODE mailing list archive at Nabble.com.
> >
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