Code for build tower

[tonyliu7870]

Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
            RaycastHit hit;
            Physics.Raycast (ray, out hit, 100f);
            if (hit.collider != null && hit.collider.tag.Equals ("Placeable")) {
                GameObject go = GameObject.Instantiate (Resources.Load ("Towers/SimpleTower") as GameObject);
                go.transform.position = hit.collider.transform.position + new Vector3 (0f, 5f, 0f);
                Quaternion quaternion = Quaternion.LookRotation (this.transform.position - hit.transform.position);
                quaternion.x = 0;
                quaternion.z = 0;
                go.transform.rotation = quaternion;
            }

[gigyun2]

added!