Unity 中的第三人称相机

第三人称摄像机 是一种放置在玩家身后的摄像机，通常稍微移至一侧，提供游戏级别和玩家本身的视觉表示。

为了在 Unity 中制作第三人称射击游戏 (TPS) 摄像机，我们将结合使用常规玩家移动和第三人称视角。

第 1 步：创建播放器控制器

首先，我们将创建一个处理旋转和移动的玩家控制器：

• 创建一个新的游戏对象（游戏对象 -> 创建空）并命名 "Player"
• 创建一个新的胶囊（游戏对象 -> 3D 对象 -> 胶囊）并将其移动到 "Player" 对象内
• 从 Capsule 中移除 Capsule Collider 组件，并将其位置更改为 (0, 1, 0)
• 创建一个新的 GameObject 并将其命名为 "CameraParent" 并将其移动到 "Player" 对象内，将其位置更改为 (0, 1.64, 0)
• 将主摄像机移动到 "CameraParent" 对象内并将其移动到播放器后面（在我的例子中，我将其移动到这个位置：(0.5, 0.6, -2.9)）

• 创建 一个新脚本，将其命名为 SC_TPSController，并将以下代码粘贴到其中：

SC_TPSController.cs

using UnityEngine;

[RequireComponent(typeof(CharacterController))]

public class SC_TPSController : MonoBehaviour
{
    public float speed = 7.5f;
    public float jumpSpeed = 8.0f;
    public float gravity = 20.0f;
    public Transform playerCameraParent;
    public float lookSpeed = 2.0f;
    public float lookXLimit = 60.0f;

    CharacterController characterController;
    Vector3 moveDirection = Vector3.zero;
    Vector2 rotation = Vector2.zero;

    [HideInInspector]
    public bool canMove = true;

    void Start()
    {
        characterController = GetComponent<CharacterController>();
        rotation.y = transform.eulerAngles.y;
    }

    void Update()
    {
        if (characterController.isGrounded)
        {
            // We are grounded, so recalculate move direction based on axes
            Vector3 forward = transform.TransformDirection(Vector3.forward);
            Vector3 right = transform.TransformDirection(Vector3.right);
            float curSpeedX = canMove ? speed * Input.GetAxis("Vertical") : 0;
            float curSpeedY = canMove ? speed * Input.GetAxis("Horizontal") : 0;
            moveDirection = (forward * curSpeedX) + (right * curSpeedY);

            if (Input.GetButton("Jump") && canMove)
            {
                moveDirection.y = jumpSpeed;
            }
        }

        // Apply gravity. Gravity is multiplied by deltaTime twice (once here, and once below
        // when the moveDirection is multiplied by deltaTime). This is because gravity should be applied
        // as an acceleration (ms^-2)
        moveDirection.y -= gravity * Time.deltaTime;

        // Move the controller
        characterController.Move(moveDirection * Time.deltaTime);

        // Player and Camera rotation
        if (canMove)
        {
            rotation.y += Input.GetAxis("Mouse X") * lookSpeed;
            rotation.x += -Input.GetAxis("Mouse Y") * lookSpeed;
            rotation.x = Mathf.Clamp(rotation.x, -lookXLimit, lookXLimit);
            playerCameraParent.localRotation = Quaternion.Euler(rotation.x, 0, 0);
            transform.eulerAngles = new Vector2(0, rotation.y);
        }
    }
}

• 将 SC_TPSController 脚本附加到 "Player" 对象（您会注意到它还添加了另一个名为“字符控制器”的组件。将其中心值更改为 (0, 1, 0)）
• 将 "CameraParent" 对象分配给 "Player Camera Parent" 变量

第2步：添加摄像头碰撞检测

Camera 碰撞检测将包含一个脚本，该脚本将检查相机和播放器之间是否有任何东西，并自动将相机移近，从而防止相机剪切对象。

• 创建一个新脚本，将其命名为 SC_CameraCollision，然后将以下代码粘贴到其中：

SC_CameraCollision.cs

using UnityEngine;

public class SC_CameraCollision : MonoBehaviour
{
    public Transform referenceTransform;
    public float collisionOffset = 0.3f; //To prevent Camera from clipping through Objects
    public float cameraSpeed = 15f; //How fast the Camera should snap into position if there are no obstacles

    Vector3 defaultPos;
    Vector3 directionNormalized;
    Transform parentTransform;
    float defaultDistance;

    // Start is called before the first frame update
    void Start()
    {
        defaultPos = transform.localPosition;
        directionNormalized = defaultPos.normalized;
        parentTransform = transform.parent;
        defaultDistance = Vector3.Distance(defaultPos, Vector3.zero);

        //Lock cursor
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;
    }

    // LateUpdate is called after Update
    void LateUpdate()
    {
        Vector3 currentPos = defaultPos;
        RaycastHit hit;
        Vector3 dirTmp = parentTransform.TransformPoint(defaultPos) - referenceTransform.position;
        if (Physics.SphereCast(referenceTransform.position, collisionOffset, dirTmp, out hit, defaultDistance))
        {
            currentPos = (directionNormalized * (hit.distance - collisionOffset));

            transform.localPosition = currentPos;
        }
        else
        {
            transform.localPosition = Vector3.Lerp(transform.localPosition, currentPos, Time.deltaTime * cameraSpeed);
        }
    }
}

• 将 SC_CameraCollision 脚本附加到主相机
• 将 "CameraParent" 对象分配给 "Reference Transform" 变量
• 调整 "Collision Offset" 和 "Camera Speed" 值，以防相机穿过墙壁

TPS 相机现已准备就绪，请按“播放”进行测试。