EnemyGenerator.cs

using UnityEngine;
using System.Collections;

public class EnemyGenerator : MonoBehaviour 
{
	#region Field
	public GameObject Enemy01;
	public GameObject Villager01;
	public float spawnRate;
	private Vector3 SelfPosition;
	private Vector3 SpawnLocationRandomize;
	private float posX;
	private float posZ;
	public float speedUpRate = 0.1f;
	// Use this for initialization
	enum CycleStat
	{
		day,
		night
	}
	static CycleStat cycle = CycleStat.night;
	#endregion
	
	void Start () 
	{
		StartCoroutine(Generate());
		//start generating enemy
	}
	
	// Update is called once per frame
	void Update () 
	{
		SelfPosition = new Vector3(transform.position.x, 0, transform.position.z);
		//keep track of self position for further usage
	}
	#region functions
	//Generate() is a coroutine that spawns different stuff according to day or night, semi randomly location wise
	IEnumerator Generate()
	{
		while(true)
		{
			while(cycle == CycleStat.night)
			{
				yield return new WaitForSeconds(spawnRate);
				posX = Random.Range (0, 3);
				posZ = Random.Range (0, 3);
				SpawnLocationRandomize = new Vector3(posX, 0, posZ);
				Instantiate(Enemy01 , SelfPosition + SpawnLocationRandomize, Quaternion.identity);
			}
			
			while(cycle == CycleStat.day)
			{
				//fill day stuff here: spawn villagers and shit
				yield return new WaitForSeconds(spawnRate);
				posX = Random.Range (0, 3);
				posZ = Random.Range (0, 3);
				SpawnLocationRandomize = new Vector3(posX, 0, posZ);
				Instantiate(Villager01 , SelfPosition + SpawnLocationRandomize, Quaternion.identity);
				
			}
		}
		
		
	}
	//cycleswitch() is a function that usually called by Timer_noGUI for day/night cycle change
	void CycleSwitch()
	{
		if (cycle == CycleStat.night)
			cycle = CycleStat.day;
		else cycle = CycleStat.night;
		Debug.Log("day/night cycle switched!");
	}
	#endregion
	void SpeedUp()
	{
		this.spawnRate = this.spawnRate * speedUpRate;
		Debug.Log("Speed Uped");
	}
}