Remote procedure calls in Unity - Mini Project: Build & Apply

Remote Procedure Calls in Unity

📖 Scenario: You are creating a simple multiplayer game in Unity where players can send messages to each other. To do this, you will use Remote Procedure Calls (RPCs) to communicate between players over the network.

🎯 Goal: Build a Unity script that uses a Remote Procedure Call to send a greeting message from one player to all other players in the game.

📋 What You'll Learn

Create a Unity C# script with a method to send a message using RPC

Set up a method that can be called remotely to display the message

Use Unity's networking system to call the RPC method

Print the received message to the Unity Console

💡 Why This Matters

🌍 Real World

Multiplayer games and networked applications use RPCs to communicate actions and data between different players or devices.

💼 Career

Understanding RPCs is important for game developers working on multiplayer games or real-time networked applications.

1

Create the basic Unity script with a message string

Create a C# script called MessageSender and inside it, declare a public string variable called message with the value "Hello from player!".

Unity

using UnityEngine;

public class MessageSender : MonoBehaviour
{
    // Your code here
}

Need a hint?

Declare a public string variable inside the class and set it to "Hello from player!".

2

Add a method to send the message using RPC

Add a public method called SendMessageToAll that uses GetComponent<PhotonView>().RPC to call a remote method named ReceiveMessage on all players. Pass the message variable as a parameter.

Unity

using UnityEngine;

public class MessageSender : MonoBehaviour
{
    public string message = "Hello from player!";

    // Your code here
}

Need a hint?

Use GetComponent<PhotonView>().RPC to call "ReceiveMessage" on all players with the message.

3

Create the remote method to receive and print the message

Add a private method called ReceiveMessage with a string parameter named receivedMessage. Mark it with [PunRPC]. Inside, use Debug.Log to print "Message received: " followed by receivedMessage.

Unity

using UnityEngine;
using Photon.Pun;

public class MessageSender : MonoBehaviour
{
    public string message = "Hello from player!";

    public void SendMessageToAll()
    {
        GetComponent().RPC("ReceiveMessage", RpcTarget.All, message);
    }

    // Your code here
}

Need a hint?

Use the [PunRPC] attribute and print the received message with Debug.Log.

4

Call the send method and display the message in Console

In the Start method, call SendMessageToAll() to send the message when the game starts.

Unity

using UnityEngine;
using Photon.Pun;

public class MessageSender : MonoBehaviour
{
    public string message = "Hello from player!";

    public void SendMessageToAll()
    {
        GetComponent().RPC("ReceiveMessage", RpcTarget.All, message);
    }

    [PunRPC]
    private void ReceiveMessage(string receivedMessage)
    {
        Debug.Log("Message received: " + receivedMessage);
    }

    // Your code here
}

Need a hint?

Use the Start method to call SendMessageToAll() when the game begins.