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FSX Sloped polys and flatten problems


Resource contributor
for the first time I need to create a sloped poly (flatten) to get the front of my airport terminal done.
As you can see in the screenshots there's a parking area (flat, above) and taxi/bus stands, that go down to a lower level in a slope. Now I got the slope done ok, the only ugly thing is the zig zag edge between the flat flatten (upper level) and the sloped flatten. Is there a way of creating a clean or smooth edge for this?


  • FlattenIssue.jpg
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If it's FSX, the easiest way is to increase your mesh res to the highest (1 metre I think) but I think this is FS9 you are using so probably not. You could make a nice smooth model 'cap' to sit over your jagged slope?

Edit: lol it is FSX, just saw the title


Resource contributor
Yes, it's FSX. I always use 5m for mesh resolution, this prevents FSX from showing ugly mesh bugs on rivers.
I thought about modeling the whole thing in 3D, but that's too much work for something that is on the backside of the airport. Just wanted to see if I missed some function in FSX or FSX-KML.
How do you specify the mesh resolution? I too have a front slope on one of my airports.

I noticed one of your roads kind of hangs in the air (the one in the background).

The problem I have with my slope is that I get old terrain showing up in the seams when FSX breaks the slope. Also, slope and flatten don't appear to mix well together.


Resource contributor
The "road" in the background is a bridge that I modeled and that leads into the terminal from the parking area.

Not sure what you mean with seams, but if you use 2 flattens at different altitudes you'll always have the problem that at the upper edge of the slope you'll have a slight bump where the terrain is elevated some inches. This can be bad if you use xml poly overlays but should not trouble you if you use 2002 ground polys or resample aerials.