NetworkTransform.clientMoveCallback2D

Description

A callback that can be used to validate on the server, the movement of client authoritative objects.

This version of the callback works with objects that use 2D physics. The callback function may return false to reject the movement request completely. It may also modify the movement parameters - which are passed by reference.

The example below set the callback in OnStartServer, and will disconnect a client that moves an object into an invalid position after a number of failures.

#pragma strict
class MyMover {
	public var cheatCount: int = 0;
	public function ValidateMove(position: Vector3, velocity: Vector3, rotation: float) {
		Debug.Log("pos:" + position);
		if (position.y > 9) {
			position.y = 9;
			cheatCount += 1;
			if (cheatCount == 10) {
				Invoke("DisconnectCheater", 0.1f);
			}
		}
		return true;
	}
	function DisconnectCheater() {
		Debug.LogError("Disconnecting cheater for movement violations " + netId);
		GetComponent.<NetworkIdentity>().connectionToClient.Disconnect();
	}
	public override function OnStartServer() {
		GetComponent.<NetworkTransform>().clientMoveCallback2D = ValidateMove;
	}
}

using UnityEngine;
using System.Collections;
using UnityEngine.Networking;
class MyMover : NetworkBehaviour
{
	public int cheatCount = 0;

	public bool ValidateMove(ref Vector2 position, ref Vector2 velocity, ref float rotation)
	{
		Debug.Log("pos:" + position);
		if (position.y > 9)
		{
			position.y = 9;
			cheatCount += 1;
			if (cheatCount == 10)
			{
				Invoke("DisconnectCheater", 0.1f);
			}
		}

		return true;
	}

	void DisconnectCheater()
	{
		Debug.LogError("Disconnecting cheater for movement violations " + netId);
		GetComponent<NetworkIdentity>().connectionToClient.Disconnect();
	}

	public override void OnStartServer()
	{
		GetComponent<NetworkTransform>().clientMoveCallback2D = ValidateMove;
	}
}

This kind of server-side movement validation should be used in conjunction with client side movement validation. The callback should only detect a failure if a client is by-passing client side movement checks - by cheating.