How can rotate the gameobject only around the y axis?

Questions & Answers
1

The gameobject should rotate only around y axis. PlayerDistance should not be changed. i need this for another script. The gameobjects should look to the player. (when the playerdistance < 10) (my english is bad sorry).

using UnityEngine;
using System.Collections;

public class NM2 : MonoBehaviour {

 public Transform player;
 public float playerDistance;
 public float rotationDamping;
 public float x = 10f;
 // Use this for initialization
 void Start()
 {
 }
 // Update is called once per frame
 void FixedUpdate()
 {
     playerDistance = Vector3.Distance(player.position, transform.position);
     if (playerDistance < x)
     {
         lookAtPlayer();
   
         
     }
     
    
 }
 void lookAtPlayer()
 {
   Quaternion rotation = Quaternion.LookRotation(player.position - transform.position);
     transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime * rotationDamping);                     
 }
2

I was using ARFoundation and had a character I always wanted to face the AR Camera. I was having some trouble getting lookAt to work correctly and only rotating on the Y-axis. Using lookat the character seemed to always rotate on all 3 axis.

I found an old Reddit post talking about Mathf.Atan2. I found it really helpful to calculate the angle between two points and rotate the character on the y axis only. Found it very helpful.

Original Reddit post is here: Reddit - Dive into anything