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[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

>     > plasticDissipation +=
>     (shearDisp+(1/currentContactPhysics->ks)*(shearForce-prevForce)).dot(shearForce)
>
>
> If the increment is fully plastic, prevForce is the max_previous but 
> shearForce is not yet equal to the max_current value since you set
>
> shearForce *= ratio
>
> only after having determined the plasticDissipation. Is this correct?
You are right, there is some nonsense, I've been mixing two different 
formulations (also : the dot product is using the "trial" shearForce, 
and shear disp. is counted twice...).

Would it be better that way (same as Vaclav's formula for stress/strain 
in the same thread)? :


if( shearForce.squaredNorm() > maxFs ){
           Real ratio = Mathr::Sqrt(maxFs) / shearForce.norm();
           Vector3r trialForce=shearForce;//store prev force for 
definition of plastic slip
           shearForce *= ratio;
           plasticDissipation +=
           
((1/currentContactPhysics->ks)*(trialForce-shearForce))//plastic disp.
           .dot(shearForce);//active force           
}

Bruno