I am wondering how is the minimap rendered...
That's because i see stuff on the minimap that i would never expect to see there... Examples: craters done by explosions or the deformations in water caused by the hovercrafts...
This makes me think that the minimap is beeing rendered by making a full render of the whole map every frame...!? If true, it can't be good in terms of performance.
Map deformation, for example is usefull to see on the map (imagine a «bridge» deformed up to unpassable) but a full render of the map to the minimap could be done only once every 10 seconds or something like that, allowing us to see the (almost) present state of deformation.
If this is true, i'll post a bug/feature_request news on SourceForge.