HLAPI simple 2 player game

Question

So I'm making a simple 2 player game following this guide: https://docs.unity3d.com/Manual/UNetSetup.html but instead of 3d shooting game I'm making 2d top-down game.

One of players is on the bottom of the screen and shoots up and the second player is on top of the screen and should shoot down. However I can't figure out how do I make the second player shoot down. I tried to check if player is not a server and apply negative speed to its bullets but it doesn't seem to work.

There's a picture of what I'm working on for better understanding: alt text

Here is my code:

Script attached to player - PlayerScript.cs:

 using UnityEngine;
 using UnityEngine.Networking;
 
 public class PlayerScript : NetworkBehaviour {
     public float speed = 5.0f;
     public GameObject projectilePrefab;
     public int rpm = 120;
 
     private float lastTimeFired = 0;
     private float timeBtwnShots;
 
     void Start () {
         timeBtwnShots = 60.0f / rpm;
     }
 
     public override void OnStartLocalPlayer() {
         GetComponent<SpriteRenderer>().color = Color.black;
         if (isServer) transform.Translate(new Vector2(0, -3));
         else {
             transform.Translate(new Vector2(0, 3));
             transform.RotateAround(transform.position, Vector3.back, 180);
         }
     }
 
     void Update () {
         if (!isLocalPlayer) return;
 
         if(Input.GetKey(KeyCode.A) || Input.GetKey(KeyCode.LeftArrow))
             gameObject.transform.Translate(new Vector2(-speed * Time.deltaTime, 0));
         else if(Input.GetKey(KeyCode.D) || Input.GetKey(KeyCode.RightArrow))
             gameObject.transform.Translate(new Vector2(speed * Time.deltaTime, 0));
 
         if(Input.GetKey(KeyCode.Space)) {
             CmdFire();
         }
     }
 
     [Command]
     void CmdFire() {
         if (Time.time - lastTimeFired > timeBtwnShots) {
             GameObject g = Instantiate(projectilePrefab, transform.position + new Vector3(0, 0.5f, 0), Quaternion.identity) as GameObject;
             g.transform.parent = gameObject.transform;
             lastTimeFired = Time.time;
             NetworkServer.Spawn(g);
             Destroy(g, 3.0f);
         }
     }
 }

Script attached to fired projectiles - ProjectileScript.cs:

 using UnityEngine;
 
 public class ProjectileScript : MonoBehaviour {
     public float speed = 5.0f;
     
     void Start() {
         if (transform.parent.gameObject.GetComponent<PlayerScript>().isServer == false)
             speed *= -1;
     }
 
     void Update () {
         transform.Translate(new Vector2(0, 1) * speed * Time.deltaTime);
     }
 }

I want client to shoot down. I thought this line in ProjectileScript.cs would make it: if (transform.parent.gameObject.GetComponent<PlayerScript>().isServer == false) speed *= -1;, but it doesn't work.

BTW I've noticed a strange thing with g.transform.parent = gameObject.transform; line: sometimes it just doesn't work... Projectiles spawn without parent in objects hierarchy.

Answer 1

Ok, so After reading on the Unity manual I noticed what I was doing wrong. Now my project looks like that:

My NetworkManager game object has custom Network Manager Script:

  using UnityEngine;
  using UnityEngine.Networking;
 
   public class CustomNetworkMgr : NetworkManager {
     public Vector3 positionUpper;
     public Vector3 positionLower;
 
     public override void OnServerAddPlayer(NetworkConnection conn, short playerControllerId) {
         Vector3 position;
         Quaternion rotation;
         if (numPlayers == 0) {
             position = positionLower;
             rotation = Quaternion.identity;
         } else {
             position = positionUpper;
             rotation = Quaternion.Euler(0, 0, 180);
         }
         GameObject player = (GameObject)Instantiate(playerPrefab, position, rotation);
         NetworkServer.AddPlayerForConnection(conn, player, playerControllerId);
     }
 }

As you can see I'm assigning players positions in OnServerAddPlayer.

PlayerScript changes include:
- adding [SyncVar] private bool shootDown = false;
- changing OnStartLocalPlayer to just:
```
 public override void OnStartLocalPlayer() {
     GetComponent<SpriteRenderer>().color = Color.black;
 }
```
- In CmdFire after instantiating player object: if(shootDown) g.GetComponent<ProjectileScript>().speed *= -1;
In ProjectileScript I made speed variable a [SyncVar]

That's it! Now players shoot projectiles as intended. Gif showing how it's working now

HLAPI simple 2 player game

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