David Megginson writes: > Jim Wilson writes: > > > The new airport lighting is really impressive. At dusk it looked pretty good > > on the screen so here's a couple shots: > > > > http://www.spiderbark.com/fgfs/cubsightseeing.png > > http://www.spiderbark.com/fgfs/towerview.png > > They do look great, but I find it disturbing that the lights float so > high above the runway (especially when they come flying through the > window during the takeoff roll) -- could it have to do with a > disparity between the published airport elevation and the actual DEM > elevation?
We artifically raise the lights a bit to attempt to avoid zbuffer fighting. The formula is based on the altitude above ground and the distance away ... however, it's rough and imperfect ... We can definitely improve on what we have, but there's no perfect solution. If you turn off the zbuffering altogether then lights will show through the backs of hills and mountains. If you use zbuffering, then you have zbuffering issues. You can't really use glPolygonOffset() because these aren't really polygons. You could fiddle with nudging the near/far clip planes, but there's no way that would ever be portable between different video cards and platforms. Runways are about the worst case scenario for things like lighting and mip-mapping. 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
