Implementing the Game Manager

In this section, we will implement a Singleton and Game Manager class. We will attempt to utilize some core Unity API features to adapt the pattern for use in the engine:

1. For the first step of the process, we will implement the Singleton class. To make it easier to understand its intricacies, we will split it up into two distinct segments:

using UnityEngine;

namespace Chapter.Singleton
{
    public class  Singleton<T> : 
        MonoBehaviour where T : Component {

        private static T _instance;

        public static T Instance
        {
            get
            {
                if (_instance == null)
                {
                    _instance = FindObjectOfType<T>();

                    if (_instance == null)
                    {
                        GameObject obj = new GameObject();
                        obj.name = typeof(T).Name;
                        _instance = obj.AddComponent<T>();
                    }
                }

    ...