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Diffstat (limited to 'src/boost/libs/graph/example/astar-cities.cpp')
-rw-r--r-- | src/boost/libs/graph/example/astar-cities.cpp | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/src/boost/libs/graph/example/astar-cities.cpp b/src/boost/libs/graph/example/astar-cities.cpp new file mode 100644 index 00000000..bca64466 --- /dev/null +++ b/src/boost/libs/graph/example/astar-cities.cpp @@ -0,0 +1,224 @@ + + +// +//======================================================================= +// Copyright (c) 2004 Kristopher Beevers +// +// Distributed under the Boost Software License, Version 1.0. (See +// accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +//======================================================================= +// + + +#include <boost/graph/astar_search.hpp> +#include <boost/graph/adjacency_list.hpp> +#include <boost/graph/random.hpp> +#include <boost/random.hpp> +#include <boost/graph/graphviz.hpp> +#include <ctime> +#include <vector> +#include <list> +#include <iostream> +#include <fstream> +#include <math.h> // for sqrt + +using namespace boost; +using namespace std; + + +// auxiliary types +struct location +{ + float y, x; // lat, long +}; +typedef float cost; + +template <class Name, class LocMap> +class city_writer { +public: + city_writer(Name n, LocMap l, float _minx, float _maxx, + float _miny, float _maxy, + unsigned int _ptx, unsigned int _pty) + : name(n), loc(l), minx(_minx), maxx(_maxx), miny(_miny), + maxy(_maxy), ptx(_ptx), pty(_pty) {} + template <class Vertex> + void operator()(ostream& out, const Vertex& v) const { + float px = 1 - (loc[v].x - minx) / (maxx - minx); + float py = (loc[v].y - miny) / (maxy - miny); + out << "[label=\"" << name[v] << "\", pos=\"" + << static_cast<unsigned int>(ptx * px) << "," + << static_cast<unsigned int>(pty * py) + << "\", fontsize=\"11\"]"; + } +private: + Name name; + LocMap loc; + float minx, maxx, miny, maxy; + unsigned int ptx, pty; +}; + +template <class WeightMap> +class time_writer { +public: + time_writer(WeightMap w) : wm(w) {} + template <class Edge> + void operator()(ostream &out, const Edge& e) const { + out << "[label=\"" << wm[e] << "\", fontsize=\"11\"]"; + } +private: + WeightMap wm; +}; + + +// euclidean distance heuristic +template <class Graph, class CostType, class LocMap> +class distance_heuristic : public astar_heuristic<Graph, CostType> +{ +public: + typedef typename graph_traits<Graph>::vertex_descriptor Vertex; + distance_heuristic(LocMap l, Vertex goal) + : m_location(l), m_goal(goal) {} + CostType operator()(Vertex u) + { + CostType dx = m_location[m_goal].x - m_location[u].x; + CostType dy = m_location[m_goal].y - m_location[u].y; + return ::sqrt(dx * dx + dy * dy); + } +private: + LocMap m_location; + Vertex m_goal; +}; + + +struct found_goal {}; // exception for termination + +// visitor that terminates when we find the goal +template <class Vertex> +class astar_goal_visitor : public boost::default_astar_visitor +{ +public: + astar_goal_visitor(Vertex goal) : m_goal(goal) {} + template <class Graph> + void examine_vertex(Vertex u, Graph& g) { + if(u == m_goal) + throw found_goal(); + } +private: + Vertex m_goal; +}; + + +int main(int argc, char **argv) +{ + + // specify some types + typedef adjacency_list<listS, vecS, undirectedS, no_property, + property<edge_weight_t, cost> > mygraph_t; + typedef property_map<mygraph_t, edge_weight_t>::type WeightMap; + typedef mygraph_t::vertex_descriptor vertex; + typedef mygraph_t::edge_descriptor edge_descriptor; + typedef std::pair<int, int> edge; + + // specify data + enum nodes { + Troy, LakePlacid, Plattsburgh, Massena, Watertown, Utica, + Syracuse, Rochester, Buffalo, Ithaca, Binghamton, Woodstock, + NewYork, N + }; + const char *name[] = { + "Troy", "Lake Placid", "Plattsburgh", "Massena", + "Watertown", "Utica", "Syracuse", "Rochester", "Buffalo", + "Ithaca", "Binghamton", "Woodstock", "New York" + }; + location locations[] = { // lat/long + {42.73, 73.68}, {44.28, 73.99}, {44.70, 73.46}, + {44.93, 74.89}, {43.97, 75.91}, {43.10, 75.23}, + {43.04, 76.14}, {43.17, 77.61}, {42.89, 78.86}, + {42.44, 76.50}, {42.10, 75.91}, {42.04, 74.11}, + {40.67, 73.94} + }; + edge edge_array[] = { + edge(Troy,Utica), edge(Troy,LakePlacid), + edge(Troy,Plattsburgh), edge(LakePlacid,Plattsburgh), + edge(Plattsburgh,Massena), edge(LakePlacid,Massena), + edge(Massena,Watertown), edge(Watertown,Utica), + edge(Watertown,Syracuse), edge(Utica,Syracuse), + edge(Syracuse,Rochester), edge(Rochester,Buffalo), + edge(Syracuse,Ithaca), edge(Ithaca,Binghamton), + edge(Ithaca,Rochester), edge(Binghamton,Troy), + edge(Binghamton,Woodstock), edge(Binghamton,NewYork), + edge(Syracuse,Binghamton), edge(Woodstock,Troy), + edge(Woodstock,NewYork) + }; + unsigned int num_edges = sizeof(edge_array) / sizeof(edge); + cost weights[] = { // estimated travel time (mins) + 96, 134, 143, 65, 115, 133, 117, 116, 74, 56, + 84, 73, 69, 70, 116, 147, 173, 183, 74, 71, 124 + }; + + + // create graph + mygraph_t g(N); + WeightMap weightmap = get(edge_weight, g); + for(std::size_t j = 0; j < num_edges; ++j) { + edge_descriptor e; bool inserted; + boost::tie(e, inserted) = add_edge(edge_array[j].first, + edge_array[j].second, g); + weightmap[e] = weights[j]; + } + + + // pick random start/goal + boost::mt19937 gen(std::time(0)); + vertex start = random_vertex(g, gen); + vertex goal = random_vertex(g, gen); + + + cout << "Start vertex: " << name[start] << endl; + cout << "Goal vertex: " << name[goal] << endl; + + ofstream dotfile; + dotfile.open("test-astar-cities.dot"); + write_graphviz(dotfile, g, + city_writer<const char **, location*> + (name, locations, 73.46, 78.86, 40.67, 44.93, + 480, 400), + time_writer<WeightMap>(weightmap)); + + + vector<mygraph_t::vertex_descriptor> p(num_vertices(g)); + vector<cost> d(num_vertices(g)); + try { + // call astar named parameter interface + astar_search_tree + (g, start, + distance_heuristic<mygraph_t, cost, location*> + (locations, goal), + predecessor_map(make_iterator_property_map(p.begin(), get(vertex_index, g))). + distance_map(make_iterator_property_map(d.begin(), get(vertex_index, g))). + visitor(astar_goal_visitor<vertex>(goal))); + + + } catch(found_goal fg) { // found a path to the goal + list<vertex> shortest_path; + for(vertex v = goal;; v = p[v]) { + shortest_path.push_front(v); + if(p[v] == v) + break; + } + cout << "Shortest path from " << name[start] << " to " + << name[goal] << ": "; + list<vertex>::iterator spi = shortest_path.begin(); + cout << name[start]; + for(++spi; spi != shortest_path.end(); ++spi) + cout << " -> " << name[*spi]; + cout << endl << "Total travel time: " << d[goal] << endl; + return 0; + } + + cout << "Didn't find a path from " << name[start] << "to" + << name[goal] << "!" << endl; + return 0; + +} |