def METHOD_NAME(self):
    self.acid    = bs.traf.id
    if not self.active:
        self.lastlat = bs.traf.lat
        self.lastlon = bs.traf.lon
        self.lasttim[:] = bs.sim.simt
        return
    """Add linepieces for trails based on traffic data"""
    # Use temporary list/array for fast append
    lstlat0 = []
    lstlon0 = []
    lstlat1 = []
    lstlon1 = []
    lsttime = []
    # Check for update
    delta = bs.sim.simt - self.lasttim
    idxs = np.where(delta > self.dt)[0]
    # Add all a/c which need the update
    # if len(idxs)>0:
    #     print "len(idxs)=",len(idxs)
    for i in idxs:
        # Add to lists
        lstlat0.append(self.lastlat[i])
        lstlon0.append(self.lastlon[i])
        lstlat1.append(bs.traf.lat[i])
        lstlon1.append(bs.traf.lon[i])
        lsttime.append(bs.sim.simt)
        if isinstance(self.col, np.ndarray):
            # print type(trailcol[i])
            # print trailcol[i]
            # print "col type: ",type(self.col)
            self.col = self.col.tolist()
        type(self.col)
        self.col.append(self.accolor[i])
        # Update aircraft record
        self.lastlat[i] = bs.traf.lat[i]
        self.lastlon[i] = bs.traf.lon[i]
        self.lasttim[i] = bs.sim.simt
    # When a/c is no longer part of trail semgment,
    # it is no longer a/c data => move to the GUI buffer (send or draw)
    if self.pygame:
        # Pygame: send to drawing buffer
        self.lat0 = np.concatenate((self.lat0, np.array(lstlat0)))
        self.lon0 = np.concatenate((self.lon0, np.array(lstlon0)))
        self.lat1 = np.concatenate((self.lat1, np.array(lstlat1)))
        self.lon1 = np.concatenate((self.lon1, np.array(lstlon1)))
        self.time = np.concatenate((self.time, np.array(lsttime)))
    else:
        # QtGL: add to send buffer
        self.newlat0.extend(lstlat0)
        self.newlon0.extend(lstlon0)
        self.newlat1.extend(lstlat1)
        self.newlon1.extend(lstlon1)
    # Update colours
    self.fcol = (1. - np.minimum(self.tcol0, np.abs(bs.sim.simt - self.time)) / self.tcol0)
    return