Upward.h

/**
 * @file
 *  This file is part of PUML
 *
 *  For conditions of distribution and use, please see the copyright
 *  notice in the file 'COPYING' at the root directory of this package
 *  and the copyright notice at https://github.com/TUM-I5/PUMGen
 *
 * @copyright 2017 Technische Universitaet Muenchen
 * @author Sebastian Rettenberger <sebastian.rettenberger@tum.de>
 */

#ifndef PUML_UPWARD_H
#define PUML_UPWARD_H

#include <algorithm>
#include <cassert>
#include <cstring>

#include "PUML.h"
#include "Topology.h"

namespace PUML
{

class Upward
{
public:
	/**
	 * Returns all local cell ids for a face
	 *
	 * @param puml The PUML mesh
	 * @param cell The face for which the cells should be returned
	 * @param lid The local ids of the cells
	 */
	template<TopoType Topo>
	static void cells(const PUML<Topo> &puml, const typename PUML<Topo>::face_t &face, int* lid)
	{
		memcpy(lid, face.m_upward, 2 * sizeof(int));
	}

	template<TopoType Topo, bool M = false>
	static void faces(const PUML<Topo> &puml, const typename PUML<Topo>::edge_t &edge, std::vector<int> &lid)
	{
		merge<M>(lid, edge.m_upward);
	}

	template<TopoType Topo, bool M = false>
	static void cells(const PUML<Topo> &puml, const typename PUML<Topo>::edge_t &edge, std::vector<int> &lid)
	{
		std::vector<int> faceIds;
		faces(puml, edge, faceIds);

		std::vector<int> cellIds;
		for (std::vector<int>::const_iterator it = faceIds.begin();
				it != faceIds.end(); ++it) {
			int tmp[2];
			cells(puml, puml.faces()[*it], tmp);
			unsigned int c = (tmp[1] < 0 ? 1 : 2);

			std::vector<int> merged;
			std::set_union(cellIds.begin(), cellIds.end(),
				tmp, tmp+c,
				std::back_inserter(merged));
			std::swap(merged, cellIds);
		}

		if (M)
			merge<true>(lid, cellIds);
		else
			std::swap(lid, cellIds);
	}

	template<TopoType Topo, bool M = false>
	static void edges(const PUML<Topo> &puml, const typename PUML<Topo>::vertex_t &vertex, std::vector<int> &lid)
	{
		merge<M>(lid, vertex.m_upward);
	}

	template<TopoType Topo, bool M = false>
	static void cells(const PUML<Topo> &puml, const typename PUML<Topo>::vertex_t &vertex, std::vector<int> &lid)
	{
		std::vector<int> edgeIds;
		edges(puml, vertex, edgeIds);

		std::vector<int> cellIds;
		for (std::vector<int>::const_iterator it = edgeIds.begin();
				it != edgeIds.end(); ++it) {
			merge<true>(cellIds, puml.edges()[*it].m_upward);
		}

		if (M)
			merge<true>(lid, cellIds);
		else
			std::swap(lid, cellIds);
	}

private:
	template<bool M>
	static void merge(std::vector<int> &res, const std::vector<int> &v);
};

template<> inline
void Upward::merge<false>(std::vector<int> &res, const std::vector<int> &v)
{
	res = v;
}

template<> inline
void Upward::merge<true>(std::vector<int> &res, const std::vector<int> &v)
{
	std::vector<int> tmp;
	std::set_union(v.begin(), v.end(),
		res.begin(), res.end(),
		std::back_inserter(tmp));
	std::swap(tmp, res);
}

}

#endif // PUML_UPWARD_H