VRMouseLook.cs

using UnityEngine;
using UnityEngine.VR;

public class VRMouseLook : MonoBehaviour {

#if UNITY_EDITOR

    public bool enableYaw = true;
    public bool autoRecenterPitch = true;
    public bool autoRecenterRoll = true;
    public KeyCode HorizontalAndVerticalKey = KeyCode.LeftAlt;
    public KeyCode RollKey = KeyCode.LeftControl;

    Transform vrCameraTransform;
    Transform rotationTransform;
    Transform forwardTransform;

    private float mouseX = 0;
    private float mouseY = 0;
    private float mouseZ = 0;

    void Awake() {
        // get the vr camera so we can align our forward with it
        Camera vrCamera = gameObject.GetComponentInChildren<Camera>();
        vrCameraTransform = vrCamera.transform;

        // create a hierarchy to enable us to additionally rotate the vr camera
        rotationTransform = new GameObject("VR Mouse Look (Rotation)").GetComponent<Transform>();
        forwardTransform = new GameObject("VR Mouse Look (Forward)").GetComponent<Transform>();
        rotationTransform.SetParent(transform.parent, false);
        forwardTransform.SetParent(rotationTransform, false);
        transform.SetParent(forwardTransform, false);
    }

    void Update () {
        bool rolled = false;
        bool pitched = false;
        if (Input.GetKey(HorizontalAndVerticalKey)) {
            pitched = true;
            if (enableYaw) {
                mouseX += Input.GetAxis("Mouse X") * 5;
                if (mouseX <= -180) {
                    mouseX += 360;
                } else if (mouseX > 180) {
                    mouseX -= 360;
                }
            }
            mouseY -= Input.GetAxis("Mouse Y") * 2.4f;
            mouseY = Mathf.Clamp(mouseY, -85, 85);
        } else if (Input.GetKey(RollKey)) {
            rolled = true;
            mouseZ += Input.GetAxis("Mouse X") * 5;
            mouseZ = Mathf.Clamp(mouseZ, -85, 85);
        }
        if (!rolled && autoRecenterRoll) {
            // People don't usually leave their heads tilted to one side for long.
            mouseZ = Mathf.Lerp(mouseZ, 0, Time.deltaTime / (Time.deltaTime + 0.1f));
        }
        if (!pitched && autoRecenterPitch) {
            // People don't usually leave their heads tilted to one side for long.
            mouseY = Mathf.Lerp(mouseY, 0, Time.deltaTime / (Time.deltaTime + 0.1f));
        }

        forwardTransform.localRotation = Quaternion.Inverse(Quaternion.Euler(0.0f, vrCameraTransform.localRotation.eulerAngles.y, 0.0f));
        rotationTransform.localRotation = Quaternion.Euler(0, vrCameraTransform.localRotation.eulerAngles.y, 0.0f) * Quaternion.Euler(mouseY, mouseX, mouseZ);
    }


#endif
}