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.
polygons to scenery. It uses the regular XML property format, which
users can create easily in a text editor. See
src/Prep/UserDef/sample.xml for examples.