Re: [Flightgear-devel] Traffic 2020: Towards a new Development Model for FlightGear AI Traffic

[Thorsten R. <tho...@sc...>]

> Agreed. One thought just struck me, which is that we could incorporate a  
> copy of the detailed weather subsystem server side, so that we could  
> generate consistent weather across sessions, without the need to had  
> that generated from within FlightGear.

Basically no - it's a plane-centered approach - it won't translate into a  
global weather server and it won't naturally give two planes in  
approximately the same location precisely the same weather (apart from  
METAR reported parameters which would agree - but there's an inifinity of  
ways to have scattered cloud cover).

Years ago ideas were discussed and I worked out a neat way of  
approximately synchronizing it in a peer-to-peer fashion among MP  
participants (assuming they all run on METAR, which seems the thing on MP).

Basically the first plane gets to build the weather tile is in the  
vicinity, any plane that reaches the area queries the plane already there  
whether it has weather tiles available or not, if yes it queries for the  
information to build them, if not it does it itself and announces their  
availability. This doesn't have to be high bandwidth because the  
meta-information to build a tile is very small (a random seed and a  
handful of parameters) and decision times can be of order of minutes.

It strikes me that Richard's emesary framework would be ideal for this  
sort of thing. The changes AW side would be modest - basically a shift to  
a dedicated random number generator, a routine to build a tile based on  
incoming information, one to store and encode the meta-data of tiles  
already created and that'd basically be it.

I never did anything into this direction because I don't do MP myself, I  
have no opportunity to test and developing  blind without being able to  
see how it works isn't what I consider fun... But that's the kind of thing  
I would do to synchronize weather across sessions.
* Thorsten