situations
- Made the code a bit more robust and able to handle the handful of rare
occasions when the least squares nurbs interpolator fails.
- Add airport surface bases for towers, windsocks, beacons, and vasi/papi
lighting so they never are buried and never float. (I'm considering the
idea of doing this for the approach lighting too ...)
surface. I think I have this working robustly.
A few miscellaneous tweaks to handle latest X-Plane data (with a few new
runway surface codes we hadn't seen before.)
caused missing output (and thus missing scenery features.) This could
also lead to cracks in the scenery because of the nature of the underlying
edge matching system.
polygons. This was to bail us out of the overwhelming memory requirments
when using the default polygon clipping routines on really large polygons.
However, the simplistic polygon partitioner did not handle holes.
Unfortunately, several TG utilities were calling this function with polygons
that did contain holes with potentially mixed results.
I renamed this function tgChopBigSimplePolygon() and created a new
tgChopNormalPolygon() which should be used by most utilities unless you
really know what you are doing.
This has some performance implications, but achieves more correct results.
branch. Kind of an out and back. node[n] == node[n+2] where there is some unique point in between. Our triangulator is usually robust to this, but not in
100% of all cases. So I had some code to catch and eliminate this weirdness.
However, a key piece of code was commented out (?!?) rendering it a no-op.
I fixed this and tile building is more robust now.
There are quite a few difficult cases where an airport is located on top
of a hill, or in a bowl, or has a significant elevation change near by.
I take the average elevation of the area and clamp the outlyers. However
these difficult cases "bias" the average elevation because the airport
surface may include much of the surrounding area.
This change to the code computes the airport elevation *only* based on the
actual airport geometry node and ignores all the surrounding nonsense that
might exist. This doesn't make things perfect, but is a *big* step forward
for airports in areas with significant elevation change nearby.
precision with floats.
- Restructure how the airport surface is sampled just a bit.
- Solving for X,Y given U,V on a nurbs surface is a little bit tricker than
I first thought. If you change one demension of U or V, you can change
both X and Y. We need to solve for each X, Y axis independently, and
then iterate in case moving in the other axis has taken us away from the
solution in the first axis.
- Add a slope constraint on airport surfaces.
Expose a polygon function that will split up long edge lines to keep the
max edge distance below some threshold. This could be used for instance
to reduce long lines in polygon area shapes so they can better follow
the underlying terrain changes.
