using UnityEngine;
using System.Collections;

[AddComponentMenu("Camera-Control/Mouse Orbit with zoom")]
public class MouseOrbitImproved : MonoBehaviour {

public Transform target;
public float distance = 5.0f;
public float xSpeed = 120.0f;
public float ySpeed = 120.0f;

public float yMinLimit = -20f;
public float yMaxLimit = 80f;

public float distanceMin = .5f;
public float distanceMax = 15f;

private Rigidbody rigidbody;

float x = 0.0f;
float y = 0.0f;

// Use this for initialization
void Start ()
{
    Vector3 angles = transform.eulerAngles;
    x = angles.y;
    y = angles.x;

    rigidbody = GetComponent<Rigidbody>();

    // Make the rigid body not change rotation
    if (rigidbody != null)
    {
        rigidbody.freezeRotation = true;
    }
}

void LateUpdate ()
{
    if (target)
    {
        x += Input.GetAxis("Mouse X") * xSpeed * distance * 0.02f;
        y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f;

        y = ClampAngle(y, yMinLimit, yMaxLimit);

        Quaternion rotation = Quaternion.Euler(y, x, 0);

        distance = Mathf.Clamp(distance - Input.GetAxis("Mouse ScrollWheel")*5, distanceMin, distanceMax);

        RaycastHit hit;
        if (Physics.Linecast (target.position, transform.position, out hit))
        {
            distance -=  hit.distance;
        }
        Vector3 negDistance = new Vector3(0.0f, 0.0f, -distance);
        Vector3 position = rotation * negDistance + target.position;

        transform.rotation = rotation;
        transform.position = position;
    }
}

public static float ClampAngle(float angle, float min, float max)
{
    if (angle < -360F)
        angle += 360F;
    if (angle > 360F)
        angle -= 360F;
    return Mathf.Clamp(angle, min, max);
}
}