use rtti and the new CanIgnore class to hand the ignorenodes to any base...

use rtti and the new CanIgnore class to hand the ignorenodes to any base solver that can handle them

[[Imported from SVN: r2503]]

dune-solvers/iterationsteps/multigridstep.cc

@@ -109,6 +109,10 @@ void MultigridStep<OperatorType, VectorType, BitVectorType>::preprocess()
     if (this->basesolver_ == NULL)
         DUNE_THROW(SolverError, "You have not provided a base solver!");
 
+    // If the base solver can ignore dofs give it the ignoreNodes field
+    if (dynamic_cast<CanIgnore<BitVectorType>*>(this->basesolver_))
+        dynamic_cast<CanIgnore<BitVectorType>*>(this->basesolver_)->ignoreNodes_ = ignoreNodesHierarchy_[0];
+
     typedef ::LoopSolver<VectorType> DuneSolversLoopSolver;
 
     if (typeid(*this->basesolver_) == typeid(DuneSolversLoopSolver)) {
@@ -128,8 +132,6 @@ void MultigridStep<OperatorType, VectorType, BitVectorType>::preprocess()
         QuadraticIPOptSolver<OperatorType,VectorType>* ipoptBaseSolver = dynamic_cast<QuadraticIPOptSolver<OperatorType,VectorType>*> (this->basesolver_);
      
         ipoptBaseSolver->setProblem(*(this->mat_[0]), this->x_[0], this->rhs_[0]);
-        ipoptBaseSolver->ignoreNodes_ = ignoreNodesHierarchy_[0];
-
     } 
 #endif
 else {