bool SetLinkVelocity(object pylink, object linearvel, object angularvel)
 {
     CHECK_POINTER(pylink);
     return _pPhysicsEngine->SetLinkVelocity(openravepy::GetKinBodyLink(pylink),ExtractVector3(linearvel),ExtractVector3(angularvel));
 }
 void SetGravity(object gravity) {
     _pPhysicsEngine->SetGravity(ExtractVector3(gravity));
 }
 bool SetBodyForce(object pylink, object force, object position, bool bAdd)
 {
     CHECK_POINTER(pylink);
     return _pPhysicsEngine->SetBodyForce(openravepy::GetKinBodyLink(pylink),ExtractVector3(force),ExtractVector3(position),bAdd);
 }
 bool SetBodyTorque(object pylink, object torque, bool bAdd)
 {
     CHECK_POINTER(pylink);
     return _pPhysicsEngine->SetBodyTorque(openravepy::GetKinBodyLink(pylink),ExtractVector3(torque),bAdd);
 }
 void SetBkgndColor(object ocolor) {
     _pviewer->SetBkgndColor(ExtractVector3(ocolor));
 }