(C#) FogFXManager.cs

using UnityEngine;

public class FogFXManager : MonoBehaviour
{
	#region Const Member Variables
	const int NUM_FOG_SYSTEMS = 4;
	#endregion

	#region Public Member Variables
	public ParticleSystem widePrefab;
	public ParticleSystem tallPrefab;
	#endregion

	#region Private Member Variables
	Camera cam;
	#endregion

	void Start()
	{
		cam = Camera.main;
		GenerateFog();
	}

	//==============================

	void GenerateFog()
	{
		Vector3 pos = Vector3.zero;
		Quaternion rot = Quaternion.identity;

		for(int i = 0; i < NUM_FOG_SYSTEMS; i++)
		{
			switch(i)
			{
				case 0:
					//top left corner
					pos = cam.ScreenToWorldPoint(new Vector3(-30f, cam.pixelHeight, 0f));
					rot.eulerAngles = new Vector3(0f, 90f, 0f);
					Instantiate(widePrefab, pos, rot, gameObject.transform);
					break;
				case 1:
					//bottom right
					pos = cam.ScreenToWorldPoint(new Vector3(cam.pixelWidth + 30f, 0f, 0f));
					rot.eulerAngles = new Vector3(0f, -90f, 0f);
					Instantiate(widePrefab, pos, rot, gameObject.transform);
					break;
				case 2:
					//bottom left
					pos = cam.ScreenToWorldPoint(new Vector3(0f, -30f, 0f));
					rot.eulerAngles = new Vector3(-90f, 0f, 0f);
					Instantiate(tallPrefab, pos, rot, gameObject.transform);
					break;
				case 3:
					//top right
					pos = cam.ScreenToWorldPoint(new Vector3(cam.pixelWidth, cam.pixelHeight + 30f, 0f));
					rot.eulerAngles = new Vector3(90f, 0f, 0f);
					Instantiate(tallPrefab, pos, rot, gameObject.transform);
					break;
				default:
					Debug.LogWarning("Out of range index accessed in fogSystems!");
					break;
			}
		}
	}
}