I plan an app which will plot aircraft, maybe on an OSM Leaflet map, maybe on Google maps. I may implement it in Flutter/Dart AngularJs, or even plain old JS.
I don't have a strong preference, and can code any/all of those, so will use whatever fits in with any good recommendation that I get here.
Is there any gratis library which will let me overlay a classic green & black radar display over a map on which I have placed icons. E.g 'plane icons on a map of the airspace around Frankfurt airport.
A bonus would be if the user can zoom the map.
Also nice, if there is a "sweep hand" rotating every few seconds.
[Update] I never did find a library, but I managed it by adapting the code found at