[Boost-users] [BGL] and dijkstra_shortest_paths...

From: Stefan Walkner (swalkner_at_[hidden])
Date: 2008-05-21 17:51:46

Hello,
sorry, I guess this is a noob question but after struggling along with
property definitions etc. I cannot find the problem with my code:
I simply can not figure out, why my dijkstra_shortest_paths invocation is
not correct... I searched around the net but nothing helped me...

Thanks in advance for any suggestions!

---------------------------------------------------

#include "boost/config.hpp"
#include <iostream>
#include <fstream>

#include "boost/graph/graph_traits.hpp"
#include "boost/graph/adjacency_list.hpp"
#include "boost/graph/dijkstra_shortest_paths.hpp"

using namespace std;
using namespace boost;

typedef enum {
    ePositive,
     eNegative
} EdgeDirection_t;

struct EdgeProperties {
    uint8_t level;
    uint16_t length;
    uint8_t angle;
    EdgeDirection_t direction;
};

struct VertexProperties {
    uint32_t index;
    uint32_t id;
    uint8_t level;
};

// define type for graph types
typedef adjacency_list <vecS , listS, directedS, VertexProperties,
EdgeProperties> Graph;

int main(int argc, char** argv)
{
    Graph graph;

    property_map<Graph, uint32_t VertexProperties::*>::type vIndex =
get(&VertexProperties::index, graph);
    property_map<Graph, uint32_t VertexProperties::*>::type vId =
get(&VertexProperties::id, graph);
    property_map<Graph, uint8_t VertexProperties::*>::type vLevel =
get(&VertexProperties::level, graph);

    typedef graph_traits<Graph>::vertex_descriptor Vertex;
    Vertex v1, v2;
    v1 = add_vertex(graph);
    vIndex[v1] = 0;
    vId[v1] = 1;
    vLevel[v1] = 1;

    v2 = add_vertex(graph);
    vIndex[v2] = 1;
    vId[v2] = 2;
    vLevel[v2] = 1;

    EdgeProperties e1;
    e1.level = 10;
    e1.length = 2000;
    e1.angle = 90;
    e1.direction = ePositive;
    add_edge(v1, v2, e1, graph);

    typedef graph_traits<Graph>::vertex_descriptor VertexDescriptor;
    std::vector<VertexDescriptor> p(num_vertices(graph));
    std::vector<int> d(num_vertices(graph));

// BOTH lines to not work ;(
// and I have no clue why...
    //dijkstra_shortest_paths(graph, v1,
predecessor_map(&p[0]).distance_map(&d[0]));
    dijkstra_shortest_paths(graph, v1,
        vertex_index_map(vIndex).
        predecessor_map(&p[0]).
        weight_map(get(&EdgeProperties::length, graph)).
        distance_map(&d[0])
    );

    exit(EXIT_SUCCESS);
}