GitHub - NPTP/UnityPlayerLoopUtility: Small easy-to-use utility for hooking delegates into Unity PlayerLoop updates

using UnityEngine;

namespace NPTP.PlayerLoopUtilities
{
    public class Example
    {
        private float updateTimeElapsed;
        private float fixedUpdateTimeElapsed;
        
        // There are two ways to use this utility: directly un/subscribing methods to different parts of the player loop,
        // or applying attributes to static methods to have them inserted into the desired part of the player loop at runtime.
        // This is how to use it with a static method:
        
        [PlayerLoopUpdate(typeof(UpdateType.FixedUpdate))]
        private static void StaticFixedUpdater()
        {
            Debug.Log("This will run on every fixed update once the first scene has finished loading.");
        }
        
        // And below is how to use it for an instantiable class:
        
        public Example()
        {
            // Subscribe wherever you like, in Awake, Start, constructors, on certain game conditions, etc.
            PlayerLoopUtility.OnPlayerLoopUpdate += PlayerLoopUpdate;
            PlayerLoopUtility.OnPlayerLoopFixedUpdate += PlayerLoopFixedUpdate;
        }

        private void PlayerLoopUpdate()
        {
            // Update logic goes here that will execute every frame, even in this non-MonoBehaviour class.
            // (You can use it in MonoBehaviours as well, if you really want to)
            updateTimeElapsed += Time.deltaTime;
            Debug.Log($"Update time elapsed: {updateTimeElapsed}");
        }

        private void PlayerLoopFixedUpdate()
        {
            // FixedUpdate logic goes here that will execute every frame, even in this non-MonoBehaviour class.
            // (You can use it in MonoBehaviours as well, if you really want to)
            fixedUpdateTimeElapsed += Time.fixedDeltaTime;
            Debug.Log($"FixedUpdate time elapsed: {fixedUpdateTimeElapsed}");
        }

        public void Terminate()
        {
            // It's highly recommended to tear down any usage when you're done.
            PlayerLoopUtility.OnPlayerLoopUpdate -= PlayerLoopUpdate;
            PlayerLoopUtility.OnPlayerLoopFixedUpdate -= PlayerLoopFixedUpdate;
        }
        
        // NOTE: In the editor, the Player Loop Utility will automatically stop any internal delegates attached to
        // the player loop before exiting play mode as a safety precaution. (This includes any static methods
        // inserted into the player loop using the PlayerLoopUpdate attribute.)
        // This is done to prevent a side effect where some PlayerLoop functionality can continue into edit mode.
    }
}