弧线运动

using UnityEngine;
using System.Collections;

public class ArcMovement : MonoBehaviour {
    public Transform sunRise;

    public Transform sunSet;

    void Update()
    {
        Vector3 center = (sunRise.position + sunSet.position) * 0.5f;

        center -= new Vector3(0, 1, 0);

        Vector3 riseRelCenter = sunRise.position - center;

        Vector3 setRelCenter = sunSet.position - center;

        transform.position = Vector3.Slerp(riseRelCenter, setRelCenter, Time.deltaTime);

        transform.position += center;
    }
}