PlaceCube.cs

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

public class PlaceCube : MonoBehaviour
{
    // Use this for initialization
    void Start ()
    {

    }

    // Update is called once per frame
    void Update ()
    {
        if(Input.GetMouseButtonDown(0))
        {
            Vector2 screenpos = new Vector2(Input.mousePosition.x, Input.mousePosition.y);
            Vector3 worldpos;
            if(ZEDSupportFunctions.GetWorldPositionAtPixel(screenpos, ZEDManager.Instance.GetLeftCameraTransform().GetComponent<Camera>(), out worldpos))
            {
                GetComponent<Rigidbody>().velocity = Vector3.zero;
                transform.position = worldpos + Vector3.up;
            }
        }
    }
}