private void AddAdjacentNodes(Node node)
{
Node neighbour;
AdjacentNode an;
foreach (Edge edge in node.Edges)
{
neighbour = GetNeighbourNode(node, edge);
if (cbDirectedGraph.Checked && neighbour != edge.DestNode)
{
continue;
}
if ((node.EdgeCameFrom == null || neighbour != GetNeighbourNode(node, node.EdgeCameFrom)))
{
if (!_sptSet.Contains(neighbour))
{
if (_adjacentNodes.HasNode(neighbour))
{
if (node.TotalCost + edge.Distance < neighbour.TotalCost)
{
an = _adjacentNodes.GetAdjacentNode(neighbour);
an.EdgeCameFrom = edge;
}
}
else
{
an = new AdjacentNode(neighbour, edge);
_adjacentNodes.AddAdjacentNode(an);
}
}
}
}
}
public TerrainNode[] FindPath(Vector3 start_position, Transform target_transform)
{
TerrainNode start_node = terrain_nodes_list.FindClosestTerrainNodeToPoint(start_position);
TerrainNode target_node = terrain_nodes_list.FindTerrainNodeFromTransform(target_transform);
//print (target_node.transform.name);
AdjacentNode closest_node_to_target = new AdjacentNode(start_node, Vector3.Distance(start_node.position, target_node.position));
Heap <TerrainNode> open_set = new Heap <TerrainNode>(terrain_size);
HashSet <TerrainNode> closed_set = new HashSet <TerrainNode>();
open_set.Add(start_node);
//start_node.transform.gameObject.GetComponent<Renderer>().material = mat_start;
//target_node.transform.gameObject.GetComponent<Renderer>().material = mat_target;
// A* pathfinding algorithm
while (open_set.Count > 0)
{
TerrainNode current_node = open_set.RemoveFirst();
closed_set.Add(current_node);
//current_node.transform.gameObject.GetComponent<Renderer>().material = mat_path;
if (current_node == target_node)
{
return(RetracePath(start_node, target_node));
}
foreach (AdjacentNode adj_neighbour in current_node.GetAdjecentNodesArray())
{
TerrainNode neighbour = adj_neighbour.terrain_node;
if (closed_set.Contains(neighbour))
{
continue;
}
float new_movement_cost_to_new_neighbour = current_node.g_cost + adj_neighbour.distance;
if (new_movement_cost_to_new_neighbour < neighbour.g_cost || !open_set.Contains(neighbour))
{
neighbour.g_cost = new_movement_cost_to_new_neighbour;
neighbour.h_cost = Vector3.Distance(neighbour.position, target_node.position);
neighbour.parent = current_node;
if (!open_set.Contains(neighbour))
{
open_set.Add(neighbour);
}
else
{
open_set.UpdateItem(neighbour);
}
if (neighbour.h_cost < closest_node_to_target.distance)
{
closest_node_to_target = new AdjacentNode(neighbour, neighbour.h_cost);
}
}
}
}
// no path found, return the closest node to target
return(FindPath(start_position, closest_node_to_target.transform));
}
// Given a list of TerrainNodes, this populates/updates the TerrainNodes's adjacent_nodes list
// max_distance is the max distance the beacon is willing to travel per turn
public static void SortAdjacentNodes(List <TerrainNode> terrain_node_list, float max_distance)
{
for (int i = 0; i < terrain_node_list.Count; i++)
{
for (int j = i; j < terrain_node_list.Count; j++)
{
float distance = Vector3.Distance(terrain_node_list[i].position, terrain_node_list[j].position);
if (distance <= max_distance && distance > 0.0f)
{
terrain_node_list[i].AddAdjecentNode(new AdjacentNode(terrain_node_list[j], distance));
terrain_node_list[j].AddAdjecentNode(new AdjacentNode(terrain_node_list[i], distance));
}
}
AdjacentNode.SortAdjacentNodes(terrain_node_list[i].GetAdjecentNodesArray());
}
}
public void AddAdjecentNode(AdjacentNode adjacent_node)
{
adjacent_node_list.Add(adjacent_node);
}