Vector3.RotateTowards

# [Vector3](https://docs.unity3d.com/cn/2019.4/ScriptReference/Vector3.html).RotateTowards

public static [Vector3](https://docs.unity3d.com/cn/2019.4/ScriptReference/Vector3.html) **RotateTowards** ([Vector3](https://docs.unity3d.com/cn/2019.4/ScriptReference/Vector3.html) **current**, [Vector3](https://docs.unity3d.com/cn/2019.4/ScriptReference/Vector3.html) **target**, float **maxRadiansDelta**, float **maxMagnitudeDelta**);

## 参数

| current           | 要处理的向量。                         |
| ------------------- | ---------------------------------------- |
| target            | 目标向量。                             |
| maxRadiansDelta   | 此旋转允许的最大角度（以弧度为单位）。 |
| maxMagnitudeDelta | 此旋转允许的最大矢量幅度变化。         |

## 返回

**Vector3** RotateTowards 生成的位置。

## 描述

将向量 `current` 朝 `target` 旋转。

该函数类似于 [MoveTowards](https://docs.unity3d.com/cn/2019.4/ScriptReference/Vector3.MoveTowards.html)，但向量被视为方向而不是位置。 `current` 向量将朝 `target` 方向旋转 `maxRadiansDelta` 的角度， 但其将准确地落在目标上而不会超过目标。 如果 `current` 和 `target` 的大小不同，则在旋转期间对结果大小进行线性插值。 如果为 `maxRadiansDelta` 使用负值，则向量将朝远离 `target` 的方向旋转， 直到它指向完全相反的方向，然后停止。

另请参阅：[Quaternion.RotateTowards](https://docs.unity3d.com/cn/2019.4/ScriptReference/Quaternion.RotateTowards.html)。

```
using UnityEngine;

// To use this script, attach it to the GameObject that you would like to rotate towards another game object.
// After attaching it, go to the inspector and drag the GameObject you would like to rotate towards into the target field.
// Move the target around in the scene view to see the GameObject continuously rotate towards it.
public class Example : MonoBehaviour
{
    // The target marker.
    public Transform target;

// Angular speed in radians per sec.
    public float speed = 1.0f;

void Update()
    {
        // Determine which direction to rotate towards
        Vector3 targetDirection = target.position - transform.position;

// The step size is equal to speed times frame time.
        float singleStep = speed * Time.deltaTime;

// Rotate the forward vector towards the target direction by one step
        Vector3 newDirection = Vector3.RotateTowards(transform.forward, targetDirection, singleStep, 0.0f);

// Draw a ray pointing at our target in
        Debug.DrawRay(transform.position, newDirection, Color.red);

// Calculate a rotation a step closer to the target and applies rotation to this object
        transform.rotation = Quaternion.LookRotation(newDirection);
    }
}
```