mob/var/tmp/obj/screen/screen

mob/Login()
    screen = new(client)
    screen.Add("Pie",new/obj/pie{pixel_x=196;pixel_y=64})
    screen.Show("Pie")

obj/screen
    appearance_flags    = PLANE_MASTER
    screen_loc          = "1,1"
    New(client/c){hud=new;c.screen+=src}
    var list/hud
    proc
        Add(id,o)
            if(id in hud){return FALSE}
            hud[id] = o
            return TRUE
        Show(id)
            if(!(id in hud)){return FALSE}
            vis_contents |= hud[id]
            return TRUE
        Hide(id)
            if(!(id in hud)){return FALSE}
            vis_contents -= hud[id]
            return TRUE