61 lines
2.3 KiB
C++
61 lines
2.3 KiB
C++
// This file is part of libigl, a simple c++ geometry processing library.
|
|
//
|
|
// Copyright (C) 2015 Olga Diamanti <olga.diam@gmail.com>
|
|
//
|
|
// This Source Code Form is subject to the terms of the Mozilla Public License
|
|
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
|
|
// obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
#ifndef IGL_DIJKSTRA
|
|
#define IGL_DIJKSTRA
|
|
#include "igl_inline.h"
|
|
|
|
#include <Eigen/Core>
|
|
#include <vector>
|
|
#include <set>
|
|
|
|
namespace igl {
|
|
|
|
// Dijstra's algorithm for shortest paths, with multiple targets.
|
|
// Adapted from http://rosettacode.org/wiki/Dijkstra%27s_algorithm .
|
|
//
|
|
// Inputs:
|
|
// source index of source vertex
|
|
// targets target vector set
|
|
// VV #V list of lists of incident vertices (adjacency list), e.g.
|
|
// as returned by igl::adjacency_list
|
|
//
|
|
// Output:
|
|
// min_distance #V by 1 list of the minimum distances from source to all vertices
|
|
// previous #V by 1 list of the previous visited vertices (for each vertex) - used for backtracking
|
|
//
|
|
template <typename IndexType, typename DerivedD, typename DerivedP>
|
|
IGL_INLINE int dijkstra_compute_paths(const IndexType &source,
|
|
const std::set<IndexType> &targets,
|
|
const std::vector<std::vector<IndexType> >& VV,
|
|
Eigen::PlainObjectBase<DerivedD> &min_distance,
|
|
Eigen::PlainObjectBase<DerivedP> &previous);
|
|
|
|
// Backtracking after Dijstra's algorithm, to find shortest path.
|
|
//
|
|
// Inputs:
|
|
// vertex vertex to which we want the shortest path (from same source as above)
|
|
// previous #V by 1 list of the previous visited vertices (for each vertex) - result of Dijkstra's algorithm
|
|
//
|
|
// Output:
|
|
// path #P by 1 list of vertex indices in the shortest path from source to vertex
|
|
//
|
|
template <typename IndexType, typename DerivedP>
|
|
IGL_INLINE void dijkstra_get_shortest_path_to(const IndexType &vertex,
|
|
const Eigen::PlainObjectBase<DerivedP> &previous,
|
|
std::vector<IndexType> &path);
|
|
};
|
|
|
|
|
|
#ifndef IGL_STATIC_LIBRARY
|
|
#include "dijkstra.cpp"
|
|
#endif
|
|
|
|
|
|
#endif /* defined(IGL_DIJKSTRA) */
|