I apologize in advance considering I'm in a very complaining mood at the moment.

I've just compiled 4 square degrees of scenery around the Minneapolis/St. Paul 
area in an attempt to figure out whether or not my Alaska scenery creation 
process worked on places in the lower 48 states.

Fortunately, the answer is yes, the process works and the scenery built 
successfully. Minneapolis is kind of boring minus the lakes, but the scenery 
also looks like the upper midwest, and there are a lot of interesting rivers to 

Unfortunately, I've run into problems with what I'll call the "swirlies" and 
the "staircases".

The first is the "swirlies" - I'm sure people have seen these before, where 
someone builds a dense road network and all of a sudden all the textures are 
stretched into oblivion.

I'll call them the "swirlies" because up close the texture pattern looks like a 

The second is the "staircases". Basically, the fan constructions don't include 
any sort of centroids, so for large glaciers the elevation literally goes up in 
steps as the fans "walk" up.

This "staircases" effect also causes an issue in mountainous valleys. Sometimes 
the fan will not pick up part of the canyon floor, instead going from peak to 
peak. This can have a very pronounced effect when you are flying, and there are 
instances of this in the Alaska scenery as well (and others, but this is the 

My question is, what can I do from a data point of view to fix these problems?

I'm using v.generalize instead of v.clean in my GRASS workflow this time 
around, which is much faster and gives better results - but it doesn't clean 
any vertices.

As a result, for both Alaska and Minneapolis sceneries, there are a number of 
strange constructions with the irregular mesh.

I know how the irregular mesh is formed. I've designed a couple golf courses 
for Links 2003 using a similar method and dropping a centroid or a few really 
can help the wireframe - unfortunately I don't have access to the actual 
wireframe scenery structure, nor is this a recommended way to edit the files.

I could also use v.clean and remove some of the vertices, which in turn would 
reduce the number of fans. I know there is a limit on fans or vertices? with 
.btg files, but this scenery is only of a "medium-high" quality, and compared 
to other sceneries I've created I'm not sure there's really a need to do this 
other than for performance. Plus, I'm loathe to run v.clean because pruning 
became very, very slow sometime in between GRASS 5 and GRASS 6.4, even though 
v.generalize doesn't remove any vertices, which is a problem.

Oh, and Minneapolis/St. Paul scenery is available for anyone who wants it, but 
please email me personally because it's buggy. (However there is one very nice 
grass-runway airport which is placed on the cliff of a river - technically a 
bug but taking off is a fun challenge!)

PS - I only get around 3-6 FPS on this brand new laptop(!), and I'm finding 
with 2.4 simply launching "fgfs --airport=KMSP --aircraft=ufo" loads up local 
weather/real-time weather, which is terrible for a simple scenery flyover test 
on a poorly performing computer - I get <1 FPS because I can't change 
visibility - is there a way to disable this feature from loading on startup 
from the command line?


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