RepulsionForce.cpp

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*/
 
#include "RepulsionForce.hpp"
 
template<unsigned DIM>
RepulsionForce<DIM>::RepulsionForce()
   : GeneralisedLinearSpringForce<DIM>()
{
}
 
template<unsigned DIM>
void RepulsionForce<DIM>::AddForceContribution(AbstractCellPopulation<DIM>& rCellPopulation)
{
    // Throw an exception message if not using a NodeBasedCellPopulation
    if (dynamic_cast<NodeBasedCellPopulation<DIM>*>(&rCellPopulation) == nullptr)
    {
        EXCEPTION("RepulsionForce is to be used with a NodeBasedCellPopulation only");
    }
 
    const std::vector< std::pair<Node<DIM>*, Node<DIM>* > >& r_node_pairs = (static_cast<NodeBasedCellPopulation<DIM>*>(&rCellPopulation))->rGetNodePairs();
    for (const auto& [p_node_a, p_node_b] : r_node_pairs)
    {
        // Get the node locations
        const c_vector<double, DIM>& r_node_a_location = p_node_a->rGetLocation();
        const c_vector<double, DIM>& r_node_b_location = p_node_b->rGetLocation();
 
        // Get the node radii
        double node_a_radius = p_node_a->GetRadius();
        double node_b_radius = p_node_b->GetRadius();
 
        // Get the unit vector parallel to the line joining the two nodes
        c_vector<double, DIM> unit_difference;
 
        unit_difference = (static_cast<NodeBasedCellPopulation<DIM>*>(&rCellPopulation))->rGetMesh().GetVectorFromAtoB(r_node_a_location, r_node_b_location);
 
        // Calculate the value of the rest length
        double rest_length = node_a_radius+node_b_radius;
 
        if (norm_2(unit_difference) < rest_length)
        {
            // Calculate the force between nodes
            c_vector<double, DIM> force = this->CalculateForceBetweenNodes(p_node_a->GetIndex(), p_node_b->GetIndex(), rCellPopulation);
            c_vector<double, DIM> negative_force = -1.0 * force;
            for (unsigned j=0; j<DIM; j++)
            {
                assert(!std::isnan(force[j]));
            }
            // Add the force contribution to each node
            p_node_a->AddAppliedForceContribution(force);
            p_node_b->AddAppliedForceContribution(negative_force);
        }
    }
}
 
template<unsigned DIM>
void RepulsionForce<DIM>::OutputForceParameters(out_stream& rParamsFile)
{
    // Call direct parent class
    GeneralisedLinearSpringForce<DIM>::OutputForceParameters(rParamsFile);
}
 
// Explicit instantiation
template class RepulsionForce<1>;
template class RepulsionForce<2>;
template class RepulsionForce<3>;
 
// Serialization for Boost >= 1.36
#include "SerializationExportWrapperForCpp.hpp"
EXPORT_TEMPLATE_CLASS_SAME_DIMS(RepulsionForce)