Example Script Request: Server Auth Moving Platform

[DageTheReaper]

I am looking to setup a server auth elevator in my game, but am struggling to get it to work.

This was my plan:

• Have animated elevator on the server, which syncs to clients. The animation drives the movement, and it's sent to clients.
• Parent player to elevator (local gravity)

Video example:

chrome_IKSmjHRbGt.mp4

But it's not working. If you could create an example script that I could expand, would hugely appreciate it. Just need pointing in the right direction.

Here's my code:

using System.Collections.Generic;
using UnityEngine;
using LiteNetLibManager;

namespace MultiplayerARPG
{
    /// <summary>
    /// This script synchronizes the platform's transform across the network
    /// and ensures that any players standing on it move and rotate seamlessly
    /// with the platform without lag or poor interpolation.
    /// Attach this script to any platform GameObject.
    /// </summary>
    [RequireComponent(typeof(LiteNetLibIdentity))]
    [RequireComponent(typeof(Collider))]
    public class PlatformSync : MonoBehaviour
    {
        private LiteNetLibIdentity identity;

        // Store the platform's last position and rotation on the server
        private Vector3 lastPosition;
        private Quaternion lastRotation;

        // List of players currently on the platform
        private List<BasePlayerCharacterEntity> playersOnPlatform = new List<BasePlayerCharacterEntity>();

        private void Awake()
        {
            identity = GetComponent<LiteNetLibIdentity>();

            // Initialize last known position and rotation
            lastPosition = transform.position;
            lastRotation = transform.rotation;

            // Ensure the Collider is set as a Trigger
            Collider collider = GetComponent<Collider>();
            if (!collider.isTrigger)
            {
                collider.isTrigger = true;
                Debug.LogWarning($"{gameObject.name}: Collider was not set as Trigger. Automatically set to Trigger.");
            }
        }

        private void FixedUpdate()
        {
            // Only the server should handle synchronization
            if (!identity.IsServer)
                return;

            // Calculate movement and rotation deltas
            Vector3 currentPosition = transform.position;
            Quaternion currentRotation = transform.rotation;

            Vector3 deltaPosition = currentPosition - lastPosition;
            Quaternion deltaRotation = currentRotation * Quaternion.Inverse(lastRotation);

            // If the platform has moved or rotated
            if (deltaPosition != Vector3.zero || deltaRotation != Quaternion.identity)
            {
                // Apply movement and rotation deltas to all players on the platform
                foreach (var player in playersOnPlatform)
                {
                    if (player == null)
                        continue;

                    // Apply positional delta
                    player.transform.position += deltaPosition;

                    // Apply rotational delta
                    player.transform.rotation = deltaRotation * player.transform.rotation;

                    // Optionally, you can adjust the player's velocity or other movement parameters here
                    // to ensure smooth movement. This depends on how your character controller handles movement.
                }

                // Update last known position and rotation
                lastPosition = currentPosition;
                lastRotation = currentRotation;

                // Optionally, you can notify clients about the platform's movement here
                // if not handled automatically by LiteNetLibIdentity
            }
        }

        private void OnTriggerEnter(Collider other)
        {
            // Detect when a player steps onto the platform
            BasePlayerCharacterEntity player = other.GetComponent<BasePlayerCharacterEntity>();
            if (player != null && !playersOnPlatform.Contains(player))
            {
                playersOnPlatform.Add(player);
                // Optional: Notify the player that they're on a platform
                // This can be used for additional effects or state changes
            }
        }

        private void OnTriggerExit(Collider other)
        {
            // Detect when a player steps off the platform
            BasePlayerCharacterEntity player = other.GetComponent<BasePlayerCharacterEntity>();
            if (player != null && playersOnPlatform.Contains(player))
            {
                playersOnPlatform.Remove(player);
                // Optional: Notify the player that they've left the platform
            }
        }

        /// <summary>
        /// Optional: Visualize the trigger area in the Unity Editor for debugging purposes.
        /// </summary>
        private void OnDrawGizmosSelected()
        {
            Gizmos.color = Color.green;
            Gizmos.DrawWireCube(transform.position, GetComponent<Collider>().bounds.size);
        }
    }
}