using UnityEngine;
namespace Pathfinding.Examples {
///
/// Moves an object along a spline.
/// Helper script in the example scene called 'Moving'.
///
[HelpURL("http://arongranberg.com/astar/documentation/stable/class_pathfinding_1_1_examples_1_1_bezier_mover.php")]
public class BezierMover : MonoBehaviour {
public Transform[] points;
public float speed = 1;
public float tiltAmount = 1f;
float time = 0;
Vector3 Position (float t) {
int c = points.Length;
int pt = Mathf.FloorToInt(t) % c;
return AstarSplines.CatmullRom(points[(pt-1+c)%c].position, points[pt].position, points[(pt+1)%c].position, points[(pt+2)%c].position, t - Mathf.FloorToInt(t));
}
/// Update is called once per frame
void Update () {
float mn = time;
float mx = time+1;
while (mx - mn > 0.0001f) {
float mid = (mn+mx)/2;
Vector3 p = Position(mid);
if ((p-transform.position).sqrMagnitude > (speed*Time.deltaTime)*(speed*Time.deltaTime)) {
mx = mid;
} else {
mn = mid;
}
}
time = (mn+mx)/2;
const float dt = 0.001f;
const float dt2 = 0.15f;
Vector3 p1 = Position(time);
Vector3 p2 = Position(time+dt);
transform.position = p1;
Vector3 p3 = Position(time+dt2);
Vector3 p4 = Position(time+dt2 + dt);
// Estimate the acceleration at the current point and use it to tilt the object inwards on the curve
var acceleration = ((p4 - p3).normalized - (p2 - p1).normalized) / (p3 - p1).magnitude;
var up = new Vector3(0, 1/(tiltAmount + 0.00001f), 0) + acceleration;
transform.rotation = Quaternion.LookRotation(p2 - p1, up);
}
void OnDrawGizmos () {
if (points.Length >= 3) {
for (int i = 0; i < points.Length; i++) if (points[i] == null) return;
Gizmos.color = Color.white;
Vector3 pp = Position(0);
for (int pt = 0; pt < points.Length; pt++) {
for (int i = 1; i <= 100; i++) {
var p = Position(pt + (i / 100f));
Gizmos.DrawLine(pp, p);
pp = p;
}
}
}
}
}
}