Unity系列【Mirror示例详细分析】

示例就是最好的学习！

Tank

要做的游戏也是与射击相关的，就从Tank开始学习吧！看看哪些可以用上，哪些需要改进！

image.png

Scripts

Tank.cs

    public class Tank : NetworkBehaviour
    {
        [Header("Components")]
        public NavMeshAgent agent;
        public Animator animator;

        [Header("Movement")]
        public float rotationSpeed = 100;

        [Header("Firing")]
        public KeyCode shootKey = KeyCode.Space;
        public GameObject projectilePrefab;
        public Transform projectileMount;

        void Update()
        {
            // movement for local player
            if (!isLocalPlayer) return;

            // rotate
            float horizontal = Input.GetAxis("Horizontal");
            transform.Rotate(0, horizontal * rotationSpeed * Time.deltaTime, 0);

            // move
            float vertical = Input.GetAxis("Vertical");
            Vector3 forward = transform.TransformDirection(Vector3.forward);
            agent.velocity = forward * Mathf.Max(vertical, 0) * agent.speed;
            animator.SetBool("Moving", agent.velocity != Vector3.zero);

            // shoot
            if (Input.GetKeyDown(shootKey))
            {
                CmdFire();
            }
        }

        // this is called on the server
        [Command]
        void CmdFire()
        {
            GameObject projectile = Instantiate(projectilePrefab, projectileMount.position, transform.rotation);
            NetworkServer.Spawn(projectile);
            RpcOnFire();
        }

        // this is called on the tank that fired for all observers
        [ClientRpc]
        void RpcOnFire()
        {
            animator.SetTrigger("Shoot");
        }
    }

网络对象继承于NetworkBehaviour，而不是MonoBehaviour。

NavMeshAgent寻路导航组件

Update()

Update()函数中检测输入，水平轴是旋转，由rotationSpeed控制旋转速度。

*我们的游戏是需要旋转的时候保持原移动方向的惯性，例如在太空中转弯的感觉，与这个速度是不一样的。

TransformDirection转换到世界坐标系，更多参见1、2

如果按下“开火”键，则调用CmdFire()函数。

CmdFire()

这是一个[Command]修饰的函数，指明客户端命令。

Instantiate()复制一个子弹预制件对象，查看Instantiate用法。

子弹是网络对象，由NetworkServer.Spawn()生成，查看NetworkServer。

RpcOnFire()

这是一个[ClientRpc]修饰的函数，可以由服务端调用。

Animator怎么弄？ 官方

Projectile.cs

    public class Projectile : NetworkBehaviour
    {
        public float destroyAfter = 5;
        public Rigidbody rigidBody;
        public float force = 1000;

        public override void OnStartServer()
        {
            Invoke(nameof(DestroySelf), destroyAfter);
        }

        // set velocity for server and client. this way we don't have to sync the
        // position, because both the server and the client simulate it.
        void Start()
        {
            rigidBody.AddForce(transform.forward * force);
        }

        // destroy for everyone on the server
        [Server]
        void DestroySelf()
        {
            NetworkServer.Destroy(gameObject);
        }

        // ServerCallback because we don't want a warning if OnTriggerEnter is
        // called on the client
        [ServerCallback]
        void OnTriggerEnter(Collider co)
        {
            NetworkServer.Destroy(gameObject);
        }
    }

OnStartServer()

Invoke()方法，5秒后销毁自己DestroySelf()

Start()

Addforce直接模仿物理受力了，给物体施加一个力，也会收到其他力的作用

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Pong

image.png

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Scripts

NetworkManagerPong.cs

public class NetworkManagerPong : NetworkManager
{
    public Transform leftRacketSpawn;
    public Transform rightRacketSpawn;
    GameObject ball;

    public override void OnServerAddPlayer(NetworkConnection conn)
    {
        // add player at correct spawn position
        Transform start = numPlayers == 0 ? leftRacketSpawn : rightRacketSpawn;
        GameObject player = Instantiate(playerPrefab, start.position, start.rotation);
        NetworkServer.AddPlayerForConnection(conn, player);

        // spawn ball if two players
        if (numPlayers == 2)
        {
            ball = Instantiate(spawnPrefabs.Find(prefab => prefab.name == "Ball"));
            NetworkServer.Spawn(ball);
        }
    }

    public override void OnServerDisconnect(NetworkConnection conn)
    {
        // destroy ball
        if (ball != null)
            NetworkServer.Destroy(ball);

        // call base functionality (actually destroys the player)
        base.OnServerDisconnect(conn);
    }
}

继承自NetworkManager，主要用来处理玩家位置。

OnServerAddPlayer()函数根据是1个还是2个玩家数，设置左边或右边，如果2个玩家就生成小球。

OnServerDisconnect()函数销毁自己创建的对象。

Players.cs

    public class Player : NetworkBehaviour
    {
        public float speed = 30;
        public Rigidbody2D rigidbody2d;

        // need to use FixedUpdate for rigidbody
        void FixedUpdate()
        {
            // only let the local player control the racket.
            // don't control other player's rackets
            if (isLocalPlayer)
                rigidbody2d.velocity = new Vector2(0, Input.GetAxisRaw("Vertical")) * speed * Time.fixedDeltaTime;
        }
    }

FixedUpdate()函数仅仅控制拍子方向。

rigidbody2d

Ball.cs

    public class Ball : NetworkBehaviour
    {
        public float speed = 30;
        public Rigidbody2D rigidbody2d;

        public override void OnStartServer()
        {
            base.OnStartServer();

            // only simulate ball physics on server
            rigidbody2d.simulated = true;

            // Serve the ball from left player
            rigidbody2d.velocity = Vector2.right * speed;
        }

        float HitFactor(Vector2 ballPos, Vector2 racketPos, float racketHeight)
        {
            // ascii art:
            // ||  1 <- at the top of the racket
            // ||
            // ||  0 <- at the middle of the racket
            // ||
            // || -1 <- at the bottom of the racket
            return (ballPos.y - racketPos.y) / racketHeight;
        }

        [ServerCallback] // only call this on server
        void OnCollisionEnter2D(Collision2D col)
        {
            // Note: 'col' holds the collision information. If the
            // Ball collided with a racket, then:
            //   col.gameObject is the racket
            //   col.transform.position is the racket's position
            //   col.collider is the racket's collider

            // did we hit a racket? then we need to calculate the hit factor
            if (col.transform.GetComponent())
            {
                // Calculate y direction via hit Factor
                float y = HitFactor(transform.position,
                                    col.transform.position,
                                    col.collider.bounds.size.y);

                // Calculate x direction via opposite collision
                float x = col.relativeVelocity.x > 0 ? 1 : -1;

                // Calculate direction, make length=1 via .normalized
                Vector2 dir = new Vector2(x, y).normalized;

                // Set Velocity with dir * speed
                rigidbody2d.velocity = dir * speed;
            }
        }
    }

OnStartServer()

初始球方向

HitFactor()

判断是否打在球拍上

OnCollisionEnter2D()

碰撞处理

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Scene

image.png

Table对象由WallTop等5个对象组成，其中除DottleLine外，都挂载了Box Collider 2D组件，支持碰撞检测。

image.png

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整体流程

1. 场景初始界面，直接设计；（我们的游戏可能需要能动态下载布局生成场景）
2. Player预制，在NetworkManager中生成Player对象；
3. Player脚本中支持用户输入，响应用户操作。

参考

https://www.cnblogs.com/eangulee/p/3572037.html