Integrating path planning module

After spending 3 days wandering (aimlessly?) trying to make my code implementing boost library works, we decide to simplify it and minimize the using of the library 😦

Now the code is working but I hate it because it’s so not fancy, not implementing OOP and far from design pattern! But the must important thing is that it works, giving us the map representation in graph. Next is represent the visited node and heuristic values in graph. And at the same time I plan to revise the code. Either digging more deeper into the boost library, or developing my own library! A simple but sufficient library of my own! 😉 (as if there’s still plenty of time left, hi hi hi)

Generating graph for grid map

Vertex list and edge list have been generated and these are graph representations for correlated maps.

n = 4

n = 10

n = 20

Next to do: generating more attributes for the graph (different colors, boldness, numbers, for indicating occupancy status)

vertex_occupancy_t blallaglalalalahaia…

Creating tag types for properties :

enum vertex_occupancy_t { vertex_occupancy };
namespace boost {
BOOST_INSTALL_PROPERTY(vertex, occupancy);}

Use new property tag in the definition of properties:

typedef property<vertex_occupancy_t, int> Occ;

Create a typedef for the Graph type, bidirectionalS means undirected graph:

typedef adjacency_list<vecS, vecS, bidirectionalS, Occ> GraphCG;

Get the property map for vertex indices:

typedef property_map<GraphCG, vertex_occupancy_t>::type StatusVertex;

Declaring the graph object:

GraphCG g(num_vertices);
StatusVertex status = get(vertex_occupancy, g);

Adding the edges to the graph object:

for (int i = 0; i < num_edges; ++i)
   add_edge(edge_array[i].first, edge_array[i].second, g);

The property maps for these properties can be obtained from the graph via the get(Property, g) function:

property_map<GraphCG, vertex_occupancy_t>::type occupancy
= get(vertex_occupancy, g);

Setting occupancy for vertex:

put(occupancy, 3, 9);
put(occupancy, 9, 3);
occupancy[2] = 7; // you can use operator[] too

Accesing the vertex set:

typedef graph_traits<GraphCG>::vertex_iterator vertex_iter;
cout << "vertices(g) occupancy status = ";
pair<vertex_iter, vertex_iter> vp;  //first iterator points to the beginning,
                                    //second iterator points "past the end" of the vertices
for (vp = vertices(g); vp.first != vp.second; ++vp.first)
    cout << status[*vp.first] << " ";

Customizing Properties

Defining my own properties tags to be added to the vertex, edge and graph.

We have agreed that the information about occupancy of obstacle in the map will be stored in the vertices.

Still…

converting grid map into a graph representation and configuring the data structure.

Graph Library – A First Trial

Have explored a bit through the graph library. Have read some documentation here, and here. The example worked fine.

The library is using template. Need to learn more about it. Maybe from this book. Now reading this and this.

Next task: developing a representation of simple grid-map in graph.