如何根据玩家方向调整对象旋转？

Question

我正在尝试创建一个 2D 自上而下的射击游戏。我想为玩家设置一种方式，让玩家将枪指向他移动的方向。例如，如果玩家按住 W 和 A 键，他的枪指向右上角。当他在方向之间切换时，枪也平滑地切换。如果玩家直线上升（例如按住 W 键），则整个玩家会切换方向。

我已经成功地复制了这一点，但仅限于 6 个方向。但是，我想让玩家的移动和所有其他方向都变得平滑。 我知道必须有一个简单的答案，我就是想不通。这是我的代码，函数以其用途命名：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerController : MonoBehaviour
{
    [Header("Character Attributes:")]
    public float movementBaseSpeed = 1.0f;

    [Space]
    [Header("Weapon Statistics:")]
    public float upwardSideAngle = 30f;
    public float downwardSideAngle = -30f;
    public float idleAngle = -10f;

    [Space]
    [Header("Character Statistics:")]
    public Vector2 currentMovementDirection;
    public float currentMovementSpeed;

    [Space]
    [Header("References:")]
    public Rigidbody2D rb;
    public Animator animator;
    public GameObject weapon;

    // Update is called once per frame
    void Update()
    {
        ProcessInputs();
        Move();
        Animate();
        MoveAim();
    }

    void ProcessInputs()
    {
        currentMovementDirection = new Vector2(Input.GetAxis("Horizontal"), Input.GetAxis("Vertical"));
        currentMovementSpeed = Mathf.Clamp(currentMovementDirection.magnitude, 0.0f, 1.0f);
        currentMovementDirection.Normalize();
    }

    void Animate()
    {
        if (currentMovementDirection != Vector2.zero)
        {
            animator.SetFloat("Horizontal", currentMovementDirection.x);
            animator.SetFloat("Vertical", currentMovementDirection.y);
        }
        animator.SetFloat("Magnitude", currentMovementDirection.magnitude);
    }

    void Move()
    {
        rb.velocity = currentMovementDirection * currentMovementSpeed * movementBaseSpeed;
    }

    void MoveAim()
    {
        //When player is moving left
        if(currentMovementDirection.x < 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0, 180, 0);
        }
        //When player is moving right
        else if(currentMovementDirection.x > 0)
        {
            weapon.transform.rotation = Quaternion.identity;
        }
        //When player is moving top right
        if(currentMovementDirection.y > 0 && currentMovementDirection.x > 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0f, 0f, upwardSideAngle);
        }
        //When player is moving bottom right
        if(currentMovementDirection.y < 0 && currentMovementDirection.x > 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0f, 0f, downwardSideAngle);
        }
        //When player is moving top left
        if(currentMovementDirection.y > 0 && currentMovementDirection.x < 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0, 180, upwardSideAngle);
        }
        //When player is moving bottom left
        if (currentMovementDirection.y < 0 && currentMovementDirection.x < 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0, 180, downwardSideAngle);
        }
        //When player is standing still
        if (currentMovementDirection.y == 0 && currentMovementDirection.x == 0)
        {
            weapon.transform.rotation = Quaternion.Euler(0f, 0f, idleAngle);
        }
    }
}

Answer 1

描述您想要的另一种方式是，您希望枪的本地right 指向您移动的方向，而本地up 尽可能接近Vector3.up。 （出于数学目的，您可以互换使用 Vector3 和 Vector2。）

如果您可以解决您希望枪变换向前和向上的方向，您可以使用Quaternion.LookRotation(Vector3 forwardDirection, Vector3 upDirection) 计算枪变换的旋转。

这是一种使用矢量数学求解方向并使用Quaternion.LookRotation 分配旋转的方法。

void MoveAim()
{
    Vector3 gunRight = currentMovementDirection;
    Vector3 gunForward = Vector3.Cross(gunRight, Vector3.up);
    // Handle cases where the gun is pointing directly up or down
    if (gunForward == Vector3.zero)
    {
        gunForward = Vector3.forward;
    }

    Vector3 gunUp = Vector3.Cross(gunForward, gunRight);

    weapon.transform.rotation = Quaternion.LookRotation(gunForward, gunUp);

    //When player is standing still
    if (currentMovementDirection == Vector2.zero)
    {
        weapon.transform.rotation = Quaternion.Euler(0f, 0f, idleAngle);
    }
}