zombie_mp/Assets/Scripts/Menu/CharacterRotate.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
public class CharacterRotate : MonoBehaviour
{
    public EventTrigger trigger;
    public Vector3 speed;
    public Transform character;
    void Start()
    {
        EventTrigger.Entry entry = new EventTrigger.Entry();
        entry.eventID = EventTriggerType.Drag;
        entry.callback.AddListener(OnMouseDrag);

        trigger.triggers.Add(entry);
    }
    void OnMouseDrag(BaseEventData eventData){
        PointerEventData e = (PointerEventData) eventData as PointerEventData;
        character.Rotate(speed * e.delta.x);
    }
}