Unity

CameraRotationController

using UnityEngine;
using System.Collections;

public class raySet : MonoBehaviour { 
	float y;
	void FixedUpdate () {
		y -= Input.GetAxis("Mouse Y");
		if (y >= -90 && y <= 90) {
			Debug.Log (y);
			transform.localRotation = Quaternion.Euler (y, 0, 0);
		}
		else {
			if (y <= -90) {
				y = -90;
			}
			else if(y >= 90) {
				y = 90;
			}
		}
	}
}