persatuan mendapatkan sudut antara dua vektor
Small helper script to check angle between 2 objects in degrees (and in between 0-360).
It also includes test code for atan2Approximation, have not measured if there are any benefits using it..
Also note [ExecuteInEditMode], so it runs in editor without playmode.
using UnityEngine;
using System.Collections;
// helper script for testing angle calculation
// USAGE:
// – Attach this script to objectA and assign objectB as target
// – Then select objectA and move it around ObjectB and you can see angle values in inspector
[ExecuteInEditMode]
public class GetAngle : MonoBehaviour
{
public Transform target;
public float angle;
public float angleOpt;
void Update ()
{
if (!target) return;
var myPos = transform.position;
myPos.y = 0;
var targetPos = target.position;
targetPos.y = 0;
Vector3 toOther = (myPos – targetPos).normalized;
angle = Mathf.Atan2(toOther.z, toOther.x) * Mathf.Rad2Deg + 180;
angleOpt = atan2Approximation(toOther.z, toOther.x) * Mathf.Rad2Deg + 180;
Debug.DrawLine (myPos, targetPos, Color.yellow);
}
float atan2Approximation(float y, float x) // http://http.developer.nvidia.com/Cg/atan2.html
{
float t0, t1, t2, t3, t4;
t3 = Mathf.Abs(x);
t1 = Mathf.Abs(y);
t0 = Mathf.Max(t3, t1);
t1 = Mathf.Min(t3, t1);
t3 = 1f / t0;
t3 = t1 * t3;
t4 = t3 * t3;
t0 = – 0.013480470f;
t0 = t0 * t4 + 0.057477314f;
t0 = t0 * t4 – 0.121239071f;
t0 = t0 * t4 + 0.195635925f;
t0 = t0 * t4 – 0.332994597f;
t0 = t0 * t4 + 0.999995630f;
t3 = t0 * t3;
t3 = (Mathf.Abs(y) > Mathf.Abs(x)) ? 1.570796327f–t3 : t3;
t3 = (x < 0) ? 3.141592654f–t3:t3;
t3 = (y < 0) ? –t3 : t3;
return t3;
}
}
Kevin
