Hi!

Ralf Gerlich wrote:
> While it seems to me that the workaround should work, due to previous
> experience with TerraGear and its subtleties I would not want to bet on it.

...and I see that I was right not to bet: The workaround doesn't work.
TerraGear failed on the first try building the EDDF-area.

> The actual problem lies within TriangleJRS, the triangulation code of
> TerraGear, which - as several checks have shown - is not as robust as
> advertised regarding computational geometry predicates. The
> "point-in-triangle"-detection-code does seem to have problems if the
> respective point is pretty near to the contour of the triangle. While
> the point is perfectly inside the triangle, TriangleJRS cannot detect that.

Nope, that's not it...

I have just checked once more and found that triangles for the extremely
small triangle parts simply do not exist. They are not generated by
TriangleJRS.

This could have one of two reasons:

1) TerraGear does some specific edge-splitting when preparing the list
of nodes and constrained edges for TriangleJRS. This is sensible, but
may move the nodes of the slivers in a co-linear fashion, i.e. the
sliver parts completely vanish.

2) TriangleJRS removes the triangles for these parts as it thinks they
are too small.

After some checking it seems that 1) is the case.

I'm at it and I hope to still be able to do a rebuild as announced with
a new solution. However, don't count on it.

The call for submissions to the static scenery objects database is left
as is ;-)

Cheers,
Ralf

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