Re:OpenTrafficMap
by antman on Thursday April 30, 2026 @12:50AM
(#47958250)
What about the traffic lights on the map do they also have transmitters?
[ Parent
| on HN ]
Yes, they also have transmitters. The traffic lights send out MAPEM and SPATEM messages. They describe the layout of the lanes at the intersection as well as the red/green phase timings of the signal.
In Graz, the city where the authors live, there are 165 of such signals planned.