ModelCoverterX vs Earth Curvature vs 3D city

Hi Arno,

I extruded in 3DS using footprints, this 3D city. Now as you know the earth curvature do not make the footprints that became 3D buildings fit precisely on the background satellite ref image

Now these buildings I grouped them into sectors and I succeeded to export them to FSX however it suffers from the earth curvature alignment issue

Initially I thought moving every block and try to make it fit on the satellite background in 3DS but it is a long process and the satellite image is not high res enough to detect the exact placement.

Now I remembered that I saw a tutorial you made a while ago about MCX correcting the curvature for a large test object, is this feature implemented yet in MCX? And will it work in my case to allign each exported buildings groups?



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Hi Michel,

Yes, that feature is in the latest development release.

But is your city flat? Because that correction function does assume that the terrain elevation is the same everywhere. It will then "bend" the object to follow the curve of the earth.
Hi Arno

Thanks for the info, I just upgraded MCX and indeed I found the option.

I tried it, the buildings group is processed but when I export the scenery I get an CVX file created, I am not sure if it is the right way to export it.

In fact, the city must be placed over an elevation mesh in FSX. To do that, I imported the mesh into 3DS and by using it as a reference, I will variate the vertical position of the buildings

The buildings group you see in this screen here has already few buildings that I already variated their height as a test.

So I presume that if the city is bent and has already variated buildings heights in 3Ds, it must follow the FSX terrain?

Thanks Arno


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FSDevConf team
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Sounds like you exported a flatten BGL and not as normal FSX BGL.

If you already took the elevation into account in 3DS, I think it should indeed work.

Which coordinate system did you use to draw your buildings? MCX assumes you use the FS2004 style flat earth when correcting it for the curve in FSX.
Hi Arno,

The buildings footprints were drawn by an Architecture firm in Lebanon using Autocad. They are not georeferenced. I just brought them in 3DS Max9 and I extruded them there.

If 3DS allow for even a higher resolution background in the drawing viewport, I could move blocks around to allign with satellite image equivalents and compensate for curvature but 3DS has a limit as for the high res settings to display a big background image (satellite image).

Hence I hope MCX will help me allign the block with the satellite image of FSX

By the way do we keep the first radio button selected as for this type of correction I need?

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