A* Pathfinding Project  4.0.3
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AstarAI.cs

Full source for the simple AI written in the Get Started Guide.It should be attached to a GameObject with a Seeker and a CharacterController also attached.

using UnityEngine;
// Note this line, if it is left out, the script won't know that the class 'Path' exists and it will throw compiler errors
// This line should always be present at the top of scripts which use pathfinding
using Pathfinding;
public class AstarAI : MonoBehaviour {
public Transform targetPosition;
private Seeker seeker;
private CharacterController controller;
public Path path;
public float speed = 2;
public float nextWaypointDistance = 3;
private int currentWaypoint = 0;
public float repathRate = 0.5f;
private float lastRepath = -9999;
public void Start () {
seeker = GetComponent<Seeker>();
controller = GetComponent<CharacterController>();
}
public void OnPathComplete (Path p) {
Debug.Log("A path was calculated. Did it fail with an error? " + p.error);
// Path pooling. To avoid unnecessary allocations paths are reference counted.
// Calling Claim will increase the reference count by 1 and Release will reduce
// it by one, when it reaches zero the path will be pooled and then it may be used
// by other scripts. The ABPath.Construct or Seeker.StartPath methods will
// take a path from the pool if possible. See also the documentation page about path pooling.
p.Claim(this);
if (!p.error) {
if (path != null) path.Release(this);
path = p;
// Reset the waypoint counter so that we start to move towards the first point in the path
currentWaypoint = 0;
} else {
p.Release(this);
}
}
public void Update () {
if (Time.time - lastRepath > repathRate && seeker.IsDone()) {
lastRepath = Time.time+ Random.value*repathRate*0.5f;
// Start a new path to the targetPosition, call the the OnPathComplete function
// when the path has been calculated (which may take a few frames depending on the complexity)
seeker.StartPath(transform.position, targetPosition.position, OnPathComplete);
}
if (path == null) {
// We have no path to follow yet, so don't do anything
return;
}
if (currentWaypoint > path.vectorPath.Count) return;
if (currentWaypoint == path.vectorPath.Count) {
Debug.Log("End Of Path Reached");
currentWaypoint++;
return;
}
// Direction to the next waypoint
Vector3 dir = (path.vectorPath[currentWaypoint]-transform.position).normalized;
dir *= speed;
// Note that SimpleMove takes a velocity in meters/second, so we should not multiply by Time.deltaTime
controller.SimpleMove(dir);
// The commented line is equivalent to the one below, but the one that is used
// is slightly faster since it does not have to calculate a square root
//if (Vector3.Distance (transform.position,path.vectorPath[currentWaypoint]) < nextWaypointDistance) {
if ((transform.position-path.vectorPath[currentWaypoint]).sqrMagnitude < nextWaypointDistance*nextWaypointDistance) {
currentWaypoint++;
return;
}
}
}