Vector3.Slerp

描述

在两个向量之间进行球面插值。

通过 t 的量在 a 和 b 之间进行插值。这与线性插值（又名“lerp”）的区别在于，向量被视为方向而不是空间中的点。返回向量的方向由角度插值，其大小在 from 和 to 的大小之间进行插值。

参数 t 被钳制到 [0, 1] 范围内。

// Animates the position in an arc between sunrise and sunset.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    public Transform sunrise;
    public Transform sunset;

    // Time to move from sunrise to sunset position, in seconds.
    public float journeyTime = 1.0f;

    // The time at which the animation started.
    private float startTime;

    void Start()
    {
        // Note the time at the start of the animation.
        startTime = Time.time;
    }

    void Update()
    {
        // The center of the arc
        Vector3 center = (sunrise.position + sunset.position) * 0.5F;

        // move the center a bit downwards to make the arc vertical
        center -= new Vector3(0, 1, 0);

        // Interpolate over the arc relative to center
        Vector3 riseRelCenter = sunrise.position - center;
        Vector3 setRelCenter = sunset.position - center;

        // The fraction of the animation that has happened so far is
        // equal to the elapsed time divided by the desired time for
        // the total journey.
        float fracComplete = (Time.time - startTime) / journeyTime;

        transform.position = Vector3.Slerp(riseRelCenter, setRelCenter, fracComplete);
        transform.position += center;
    }
}

其他资源：Lerp，SlerpUnclamped。