FSX FS8/FSX Ground poly conversion: alpha issue

JonPatch

Resource contributor
#1
First, I love this FS8/FSX ground poly conversion feature! Zowie!

But I have an issue: one of the polys was lacking an alpha channel in my FS8 version. I've added it to the DDS but the revised alpha doesn't mask the areas I chose in the converted poly, either in the tool or the sim.

Is there a tweak I need to do to the poly itself?

Also, is there a way I can specify the altitude to be AGL=FALSE?

Jon
 
Last edited:

arno

Administrator
Staff member
FSDevConf team
Resource contributor
#2
Hi Jon,

As far as I know the fs2002 style ground polygons should always use the alpha channel for transparency, so I am not sure what is going on here.

About the altitude, the tool has been designed to put objects at ground level, so that's why it uses agl. What kind of polygons are you trying to make that you would like a different value?
 

JonPatch

Resource contributor
#5
Thx, Arno. The texture issue magically resolved itself. The placement issue occured when for some reason the poly was placed at 0 altitude, below the surface. Again some mucking around resolved this issue without knowing the cause. Gremlins, I guess. ;)

Jon
 

JonPatch

Resource contributor
#6
Not so fast

So the flatten was changed under the ground poly, and the behaviour of the ground poly has changed! Now one corner of it is not visible very close up, begins to flicker to life as you slew away and completely appears at a distance. It does not correspond to one of the polygons directly, but occurs corner to corner. See attached screenshot.

What's weirder is that when I re-imported the converted ground poly into MCX from FSX ONLY that misbehaving corner appears! Not the rest of the poly, or the other polys. See attached.

Ideas?
 

Attachments

arno

Administrator
Staff member
FSDevConf team
Resource contributor
#7
Hi Jon,

I think the difference when you import it again is due to splitting the object in groups. I expect that the other part is in another object.

Is the entire area that is flickering still part of the flatten? The ground polygon wizard assumes everything is the same altitude.
 

JonPatch

Resource contributor
#8
Roger on the objects, I understand now.

The entire area, including flickering and non-flickering parts, is on a single flatten. There are two objects, and now I see that one flickers and one doesn't.

Jon
 

JonPatch

Resource contributor
#9
So I playfully selected "correct for earth curvature" on both objects, re-exported, and now the previously flickering object doesn't appear at all, and the other one flickers.

(Looking up at daylight from the hole I'm digging)
 

arno

Administrator
Staff member
FSDevConf team
Resource contributor
#10
Hi Jon,

When exporting for FSX with the ground polygon wizard it is already corrected for the curve of the earth. So doing it again will make things worse in general (twice curved, so possibly below the ground).

Are you sure that you set the correct altitude in meters in the wizard when exporting the ground polygons?
 

JonPatch

Resource contributor
#11
Hi Arno,

Roger on curvature.

I didn't use the wizard. ;) I simply imported FS8 and exported FSX. I left the height at zero, as I assumed it was placed AGL.

So now I used the wizard, and the poly didn't appear. Suspecting it to be below ground level, I adjusted the height in MCX to be ground level (9.14m), and it floats above the ground. If I set the height to 4m that sets it about ground level.

Why is it not displaying either AGL or at absolute height, and instead appears to be at an arbitrary height? I checked the altitude flatten and coverage and it matches.

And that transparency issue I reported earlier has reappeared, at one corner it appears to be ignoring the alpha. It's definitely in the .DDS. The alpha was not in the original FS8 compile though, I added it later. Could that be an issue?

Most challenging!

Jon
 

arno

Administrator
Staff member
FSDevConf team
Resource contributor
#12
Hi Jon,

The idea is that in the wizard you enter the exact altitude of your flatten (in meters) and then it should work fine. I haven't had issues with floating polygons in that case. So the fiddling you had to do are not supposed to be there. Let me see if I can reproduce it somehow.
 

JonPatch

Resource contributor
#13
Hey Arno, I spoke with another developer who loves MCX and has done hundreds of ground polys and says he's never had a problem. He suggested a different approach: instead of trying to convert from the FS8 BGL to FSX BGL in MCX, I convert the gmax model to FSX, export the FSX MDL, import that to MCX and export from there. So I'm gonna give that a shot.

Thanks for your help.

Jon
 
Top