Rotating Platform

Rotate.cs

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

public class Rotate : MonoBehaviour
{
    // Rotation value
    // The [SerializeField] make it visible in the editor even though it is private
    [SerializeField] private Vector3 _rotation = Vector3.zero;
    
    // The list of all the GameObjects attached to the platform
    private List<GameObject> _attachedObjects = new List<GameObject>();

    // When a GameObject stays in collision
    // Check if it is on top of the platform
    // And add it to the list and set the parent accordingly
    private void OnCollisionStay(Collision collisionInfo) {
        // We don't want to add the GameObject to the list if is it already attached to the platform
        if (this._attachedObjects.Contains(collisionInfo.gameObject)) {
            return;
        }
        else {
            // We check every contact point of the collision
            // This ensure that if a GameObject is only half on the platform, it still works
            foreach (ContactPoint contactPoint in collisionInfo.contacts) {
                // If the point is on top of the platform
                // We add it to the list
                // And we set its parent to be the platform
                if (contactPoint.point.y > this.transform.position.y) {
                    this._attachedObjects.Add(collisionInfo.gameObject);
                    collisionInfo.transform.SetParent(this.transform);
                    return;
                }
            }
        }
    }

    // When a GameObject exits the collision with the platform
    // Remove it from the list and unparent it (if it was in the list)
    private void OnCollisionExit(Collision collisionInfo) {
        // Check if the object was in the list
        if (this._attachedObjects.Contains(collisionInfo.gameObject)) {
            // Yes ? good, then unparent it
            collisionInfo.transform.SetParent(null);
            // And finally remove it from the list
            this._attachedObjects.Remove(collisionInfo.gameObject);
        }
    }

    void Update() {
        // Rotate the platform every frame
        this.transform.Rotate(this._rotation * Time.deltaTime);
    }
}

Unity C# script

Used for rotating a platform and making the GameObjects on top of it following its movement.

What this script does:

• Detect the objects that are on top of the platform and parent them to the platform
• Unparent them when they leave the platform.
• Rotate the platform every update.