Unity tank rotation

tank_rotation.cs

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Tank : MonoBehaviour
{

    public Transform cabina;
    public Transform dulo;

    public Transform target;

	
	// Update is called once per frame
	void Update ()
	{
	    var angleY = Mathf.Rad2Deg * AngleInRadXZ(cabina.position, target.position);

	    var h = target.position.y - dulo.position.y;
        var v1 = new Vector2(dulo.position.x, dulo.position.z);
        var v2 = new Vector2(target.position.x, target.position.z);

	    var m = (v1 - v2).magnitude;

	    var a = 0f;
        if (Math.Abs(m) > 0.01f)
	        a = Mathf.Asin(h / m);

        cabina.rotation = Quaternion.Euler(cabina.rotation.eulerAngles.x, angleY, cabina.rotation.eulerAngles.x);

        dulo.localEulerAngles = new Vector3(0,0, a * Mathf.Rad2Deg);

    }

    public static float AngleInRadXZ(Vector3 vec1, Vector3 vec2)
    {
        return Mathf.Atan2( vec2.x - vec1.x, vec2.z - vec1.z) - Mathf.PI * 0.5f;
    }

}