Martin van Beilen writes: > It seems to me that fgfs has some (a lot > of?) 'orphaned' features. The problem is that the code is there, > but there's no way to activate these features, and no > documentation. > > For example, I've found that the code supports multiple cloud > layers with varying degrees of coverage, from FEW to OVC. The > required textures appear to be present. Unfortunately users can > only set the cloud base for the first layer. Its coverage is > hard-coded to BKN, and the second layer is hardcoded FEW190.
In this case, there is support at the simgear level for 'n' cloud layers each with their own properties. However, there was no 'interface' to this in flightgear and we only hardcoded in the layers. No one has gotten around to building a proper interface. Someone came along and added an option to set _just_ the bottom layer. A little strange and far from complete, but I was told it was better than nothing. Ok ... I went ahead and added the code. But, we really should fix this, and add a flightgear interface for setting arbitrary cloud layers, as well as some mechanism to change cloud layers and have the visuals smoothly adjust over some time period. > Eventually I'd like to be able to add and remove cloud layers on > the fly. I propose the following properties: > > /environment/clouds/layer[n]/ > (layers can be added from command-line, > configuration file or on-the-fly.) > > altitude-ft (double) > thickness-ft (double) > > transition-ft (double) > (what does transition do?) > > coverage (double) > [0.0 - 1.0] sky coverage fraction; also obsoletes > status property. (0 -> status=false) > > type (string) > Cumulus|Stratocumulus|Stratus|Cirrus > > speed-from-north-fps (double) > speed-from-east-fps (double) > moving clouds, not implemented yet (is the > convention for clouds to or from?) > > I'm not touching any weather-related code until this new > environment thing is resolved. I could get started on the network > interface though. I want to tread carefully here but I'll make a couple comments ... the WeatherCM code was added some time ago, but it really did very little as far as interacting with FlightGear. It mostly sat as a placeholder waiting for someone to come along and find a way to populate the database with live weather values and then build an interface so that flightgear would honor the local weather values as queried from the weather database. The flip side of this was that the FDM's really didn't do much with wind, temp, or pressure a year ago and we didn't have a way to transition between changing cloud layers. Now, the FDM's do a lot with honoring weather variables, but the weather database is complicated enough that it is difficult for anyone to come along and 'get there head around' it enough to finish the task of completely integrating it. I think what David is trying to do here is creating an alternate 'simple' weather system. Something that has much less startup overhead, something that is easier to get your head around, and something that can be more easily integrated. In some ways this is a good thing becuase if we get one weather system integrated properly and work out all the issues, then it will clear the path for the other one, so that hopefully somebody will come along and finish up the integration of WeatherCM so that it can be a fully functional system. Just like we have competing FDM's with different focus, strengths and weaknesses, I don't think it is bad to have competing weather/environment management systems with different focus, strengths and weaknesses. I don't think people should read too much into adding an alternate environment subsystem ... especially if it prompts / helps get WeatherCM more integrated and working with the rest of FGFS in the long run. Regards, Curt. -- Curtis Olson IVLab / HumanFIRST Program FlightGear Project Twin Cities [EMAIL PROTECTED] [EMAIL PROTECTED] Minnesota http://www.menet.umn.edu/~curt http://www.flightgear.org _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
