2010/5/17 Václav Šmilauer <[email protected]> > > NormShearPhys* > > phys=YADE_CAST<NormShearPhys*>(contact->interactionPhysics.get()); > > assert(phys); > > // all we need for getting stiffness > > Vector3r& normal=geom->normal; Real& kn=phys->kn; Real& ks=phys->ks; > > Real& radius1=geom->refR1; Real& radius2=geom->refR2; > > Real fn = (static_cast<NormShearPhys *> > > (contact->interactionPhysics.get()))->normalForce.squaredNorm(); > > if (fn==0) continue;//Is it a problem with some laws? I still don't > > see why. > > > > Two questions: > > 1) Why are we here casting to the class NormShearPhys instead of > > FrictPhys class? > That is to make code more generic. Only normal and shear > forces/stiffnesses are needed in the computation and that is already > provided by NormShearPhys. FrictPhys is derived from NormShearPhys, but > data added in FrictPhys are not needed. > > In this case, e.g. CpmPhys will work with GSTS (although I don't use > it), since it also derives from NormShearPhys, but not from FrictPhys. > Ok. So is the derived class object also a base class object? Exactly the same one? cheers, Chiara
> > > 2) Why do we need to continue if fn==0? > IIRC Bruno told me that was to avoid contacts that transmit no force, > even if they have non-zero nominal stiffness. Exact zero will be there > for interactions that really had no force at all. > > I am not completely persuaded on that, since most likely contacts with > exactly zero force will be already erased. Yes, that is why I was guessing about that. > > HTH, Vaclav > > > > > > _______________________________________________ > Mailing list: > https://launchpad.net/~yade-dev<https://launchpad.net/%7Eyade-dev> > Post to : [email protected] > Unsubscribe : > https://launchpad.net/~yade-dev<https://launchpad.net/%7Eyade-dev> > More help : https://help.launchpad.net/ListHelp >
_______________________________________________ Mailing list: https://launchpad.net/~yade-dev Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-dev More help : https://help.launchpad.net/ListHelp
