format. The big trick was that the polygon clipper is completely 2d. So
I needed to add code to preserve the elevations in the clipped output and
fill in plausible elevations for any new points created as a result of the
clipping.
intermediate mode. The goal then is that these elevations would be
preserved throughout the tile construction process and the surrounding
geometry would fill in without gaps. This has potential applications for
airports and runways of course as well as roads, rivers, streams, railroads,
or any other object where we might want to control the final elevation in
advance.
in .dem format. The .arr format is a much simpler (and a bit less flexible)
specifically for use as an intermediate format when building scenery. Any
number of various raw terrain formats could be translated into the common
.arr format which then greatly simplifies life for the build tiles util.
position.
Terrasync runs as a separate process and accepts the --atlas=port format.
The fgfs output tells the terrasync util where FlightGear is currently flying.
Terrasync will then issue the appropriate commands to rsync the surrounding
areas to your local scenery directory.
As you fly, terrasync will periodically refresh and pull any new scenery tiles
in the vicinity.
This also works if the scenery on the scenery server is update. Rsync will
pull any missing files, or any updated files.
There is a chicken/egg problem when you first start up in a brand new area.
FlightGear is expecting the scenery to be there *now* but it hasn't been
fetched yet. I suppose without making a more complex protocol, the user
will need to be aware of this. The user could restart flightgear after the
initial rsync completes, and then after that everything should be good,
assuming the user has the necessary bandwidth to keep up with flight speeds.
Final notes:
At the moment Alex Perry has a partial rsync server, but I don't know it's
status. I hope to have a full server up and running at some point soon.
Currently the terragear utility just echos the commands it would run to
rsync the data, it doesn't actually run the commands. This is a work in
progress.