// If this message has new position info, *and* we have good backfill, then craft a CompositeMsg.
// Note, we don't wait for squawk info.
func (s *ADSBSender) maybeCreateComposite(m *adsb.Msg) *adsb.CompositeMsg {
if !m.HasPosition() {
return nil
}
//if s.LastGroundSpeed == 0 || s.LastTrack == 0 || s.LastCallsign == "" { return nil }
cm := adsb.CompositeMsg{Msg: *m} // Clone the input into the embedded struct
// Overwrite with cached info (from previous packets), if we don't have it in this packet
if cm.GroundSpeed == 0 {
cm.GroundSpeed = s.LastGroundSpeed
}
if cm.VerticalRate == 0 {
cm.VerticalRate = s.LastVerticalSpeed
}
if cm.Track == 0 {
cm.Track = s.LastTrack
}
if cm.Callsign == "" {
cm.Callsign = s.LastCallsign
}
if cm.Squawk == "" {
cm.Squawk = s.LastSquawk
}
return &cm
}
