Instead of cleaning polys after clipping, to get good triangulation, try to
clean them before clipping, snap the verticies to 1 1cm x 1cm grid, and
merge any resultant slivers back into adjacent polys.
This is very similar to how fgfs-construct worked.
Although the previous methos only failed on 3 airports, the results weren't
very good. There were lots of cracks, and mmissing triangles, as the polys were
cleaned.
New methos freezes on two airports during base triangulation, and crashes on four.
I think the quality of the generated airports overcomes the slight regression.
I also added some debug switches so I don't have to keep rebuilding from source
to debug crashes. --dump-rwy=xxx --dump-pvmt=xxx, --dump-feat=xxx and --dum-base=1
can be used to create shapefiles to debug the particular polys before clipping.
Currently, there needs to be a cp_debug directory to place the shapefiles into.
Probably need better debug infrastructure going forward...
NOTE: I turned off runway shoulder generation in this build. Polygon snapping for runways,
helipads, and shoulders not implemented yet. This may help on the failing airports.
This is next on my todo list.
f0a7f39e7b