public List <Node> Astar(Node start, Node goal)
{
if (start == null || goal == null)
{
return(null);
}
if (start == goal)
{
return(new List <Node>()
{
start
});
}
// initialize pathfinding variables
foreach (Node node in _ObjectManager.Map.nodes)
{
node.gScore = int.MaxValue;
node.fScore = int.MaxValue;
node.parent = null;
node.isInOpenSet = false;
node.isInClosedSet = false;
}
MinHeap openSet = new MinHeap(start);
start.gScore = 0;
start.fScore = start.gScore + Heuristic_cost_estimate(start, goal);
while (openSet.heap.Count > 1)
{
// get closest node
Node current = openSet.GetRoot();
// if its the goal, return
if (current == goal)
{
return(Reconstruct_path(start, goal));
}
// look at the neighbors of the node
foreach (Node neighbor in current.getDiagnalNeighbors())
{
// ignore the ones that are unwalkable or are in the closed set
if (neighbor != null && neighbor.isWalkable && !neighbor.isInClosedSet)
{
// if the new gscore is lower replace it
int tentativeGscore = current.gScore + 14 + UnityEngine.Random.Range(0, 8);
if (!neighbor.isInOpenSet || tentativeGscore < neighbor.gScore)
{
neighbor.parent = current;
neighbor.gScore = tentativeGscore;
neighbor.fScore = neighbor.gScore + Heuristic_cost_estimate(neighbor, goal);
}
// if neighbor's not in the open set add it
if (!neighbor.isInOpenSet)
{
openSet.BubbleUp(neighbor);
}
}
}
// look at the neighbors of the node
foreach (Node neighbor in current.getCloseNeighbors())
{
// ignore the ones that are unwalkable or are in the closed set
if (neighbor != null && neighbor.isWalkable && !neighbor.isInClosedSet)
{
// if the new gscore is lower replace it
int tentativeGscore = current.gScore + 10 + UnityEngine.Random.Range(0, 8);
if (!neighbor.isInOpenSet || tentativeGscore < neighbor.gScore)
{
neighbor.parent = current;
neighbor.gScore = tentativeGscore;
neighbor.fScore = neighbor.gScore + Heuristic_cost_estimate(neighbor, goal);
}
// if neighbor's not in the open set add it
if (!neighbor.isInOpenSet)
{
openSet.BubbleUp(neighbor);
}
}
}
}
// Fail
return(null);
}
public List<Node> Astar(Node start, Node goal)
{
if (start == null || goal == null)
return null;
if (start == goal)
{
return new List<Node>()
{
start
};
}
// initialize pathfinding variables
foreach (Node node in _ObjectManager.Map.nodes) {
node.gScore = int.MaxValue;
node.fScore = int.MaxValue;
node.parent = null;
node.isInOpenSet = false;
node.isInClosedSet = false;
}
MinHeap openSet = new MinHeap (start);
start.gScore = 0;
start.fScore = start.gScore + Heuristic_cost_estimate (start, goal);
while (openSet.heap.Count > 1) {
// get closest node
Node current = openSet.GetRoot ();
// if its the goal, return
if (current == goal)
return Reconstruct_path (start, goal);
// look at the neighbors of the node
foreach (Node neighbor in current.getDiagnalNeighbors()) {
// ignore the ones that are unwalkable or are in the closed set
if (neighbor != null && neighbor.isWalkable && !neighbor.isInClosedSet) {
// if the new gscore is lower replace it
int tentativeGscore = current.gScore + 14 + UnityEngine.Random.Range (0, 8);
if (!neighbor.isInOpenSet || tentativeGscore < neighbor.gScore) {
neighbor.parent = current;
neighbor.gScore = tentativeGscore;
neighbor.fScore = neighbor.gScore + Heuristic_cost_estimate (neighbor, goal);
}
// if neighbor's not in the open set add it
if (!neighbor.isInOpenSet) {
openSet.BubbleUp (neighbor);
}
}
}
// look at the neighbors of the node
foreach (Node neighbor in current.getCloseNeighbors()) {
// ignore the ones that are unwalkable or are in the closed set
if (neighbor != null && neighbor.isWalkable && !neighbor.isInClosedSet) {
// if the new gscore is lower replace it
int tentativeGscore = current.gScore + 10 + UnityEngine.Random.Range (0, 8);
if (!neighbor.isInOpenSet || tentativeGscore < neighbor.gScore) {
neighbor.parent = current;
neighbor.gScore = tentativeGscore;
neighbor.fScore = neighbor.gScore + Heuristic_cost_estimate (neighbor, goal);
}
// if neighbor's not in the open set add it
if (!neighbor.isInOpenSet) {
openSet.BubbleUp (neighbor);
}
}
}
}
// Fail
return null;
}
