Chase camera that works in any orientation

SuperChaseCamera.cs

using UnityEngine;
using System.Collections;

public class SuperChaseCamera : MonoBehaviour
{
    public Transform m_Target;
	public Vector3 m_TargetOffset = new Vector3(0.0f, 1.0f, 0.0f);
	public Vector3 m_ChasingOffset = new Vector3(0.0f, 1.0f, -10.0f);
	public Vector3 m_LeadingOffset = new Vector3(0.0f, 1.0f, 20.0f);
	public float m_NormalisingFactor = 0.1f;

	protected Vector3 m_Position;
	protected Vector3 m_Up;
	protected Vector3 m_TargetPosition;

	delegate void View();
	View m_View;

	// Events:

	protected void Start()
	{
		m_View = ForwardView;
		ResetView();
	}

	protected void FixedUpdate()
	{
		m_View();
	}

	protected void Update()
	{
		if(Input.GetButtonDown("Rear View"))
		{
			if(m_View != ForwardView)
				m_View = ForwardView;
			else
				m_View = RearView;

			ResetView();
		}
		else if(Input.GetButtonDown("Target View"))
		{
			m_View = TargetView;

			RaycastHit hit;
			if(Physics.Raycast(m_Target.position, m_Target.forward, out hit))
				m_TargetPosition = hit.point;
			else
				m_TargetPosition = transform.forward * 10000.0f;
		}
	}

	// Delegate methods:

	protected void ForwardView()
	{
		LerpTowardsTarget(m_ChasingOffset);
	}

	protected void RearView()
	{
		LerpTowardsTarget(m_LeadingOffset);
	}

	protected void TargetView()
	{
		Vector3 targetVector = (m_TargetPosition - m_Target.position).normalized;
		transform.rotation = Quaternion.LookRotation(targetVector, m_Target.up);
		transform.position = m_Target.position + transform.rotation * new Vector3(0.0f, 2.0f, -5.0f);
	}

	// Other methods:

	protected void LerpTowardsTarget(Vector3 offset)
	{
		m_Position = Vector3.Lerp(transform.position, m_Target.TransformPoint(offset), m_NormalisingFactor);
		m_Up = Vector3.Lerp(transform.up, m_Target.up, m_NormalisingFactor);
		m_TargetPosition = Vector3.Lerp(m_TargetPosition, m_Target.TransformPoint(m_TargetOffset), m_NormalisingFactor);

		transform.position = m_Position;
		transform.LookAt(m_TargetPosition, m_Up);
	}

	protected void ResetView()
	{
		Vector3 offset = (m_View != ForwardView ? m_LeadingOffset : m_ChasingOffset);
		m_Position = m_Target.TransformPoint(offset);
		m_Up = transform.up;
		m_TargetPosition = m_Target.position;

		transform.position = m_Position;
		transform.LookAt(m_TargetPosition, m_Up);
	}
}