Unity Networking - Multiplayer Game Development

Overview

Multiplayer networking for Unity using Netcode for GameObjects, Mirror, or Photon frameworks.

Foundation Required: unity-csharp-fundamentals (TryGetComponent, FindAnyObjectByType, null-safe coding)

Core Topics:

• •Client-server architecture
• •State synchronization
• •Lag compensation
• •RPC (Remote Procedure Calls)
• •Network variables
• •Matchmaking

Quick Start (Unity Netcode)

using Unity.Netcode;

public class Player : NetworkBehaviour
{
    private NetworkVariable<int> mHealth = new(100);

    public override void OnNetworkSpawn()
    {
        if (IsOwner)
        {
            // Only owner can control
            HandleInput();
        }

        mHealth.OnValueChanged += OnHealthChanged;
    }

    [ServerRpc]
    void TakeDamageServerRpc(int damage)
    {
        mHealth.Value -= damage;
    }

    [ClientRpc]
    void ShowDamageEffectClientRpc()
    {
        // Visual feedback on all clients
    }
}

Network Architecture

• •Authoritative Server: Server validates all actions (competitive)
• •Client Authority: Clients control own entities (cooperative)
• •Relay Servers: NAT traversal for peer-to-peer
• •Dedicated Servers: Professional hosting

Synchronization Patterns

• •Transform Sync: Position, rotation interpolation
• •Network Variables: Automatic state replication
• •RPCs: Remote method calls
• •Ownership: Who can modify what

Best Practices

1. •Server authority: Prevent cheating
2. •Client prediction: Smooth movement
3. •Interpolation: Handle lag gracefully
4. •Bandwidth optimization: Delta compression
5. •Test with network simulation: Latency, packet loss