FSX, P3D Polygons

I lost an old model that I had installed in FSX so I read around and found how to decompile it and get it back from the FSX mdl file. I was a bit shocked to find that all the polygons were three sided instead of the four sided that I created the model in.

So the big question is "Does FSX and P3D only allow importing three sided polygons into the bgl and mdl files?"

CWP
 
You can export rectangles alright. Just make a test cube and export it, no problem.

However, in the compile process all polygons are converted to triangles in the mdl. So if you decompile the mdl, you get the triangles, and are basically stuck with them. Some progs such as Meshlab have a make-quadrangular function but it is not reliable. In gmax you can manually delete diagonal edges, but it's a lot of work. In FSDS I don't know if that's an option.
 
Thanks Mjahn, I spend a lot of time correcting mesh to ensure four sided polygons but if the end result is three sided polygons in sim then there is little sense on doing it for FS models. The bad news for me is that my poly count has doubled for the most part but at-least I know now!...

CWP
 

arno

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The graphics card can only render triangles anyway, so that's why all objects are broken down to triangles.

And it has nothing to do with the polygon count of course. You should only count triangles anyway.
 
Thank you Arno, that was the bottom line answer I needed to understand. So when considering draw call what is the best way to determine pixels over polygons? (example - let's say I have a flat panel on a model that would contain 1425 polygons because of the round window borders. To render it proper as a two polygon object it would need three 1024X textures split in to six 512 X 1024 sections with an alpha to exclude the window cutout areas. If I use the model part containing the 1425 polygons the part could be rendered using a single tiled 1024x texture split in to two 512 x 1024 sections. In my mind the lower draw call would be the modeled part using the 1425 polygons but I don't know the formula to confirm it...) Where would I look to figure out the best in sim results? Of course I can build the part both ways and try them in sim but I want to do it right the first time.

CWP
 

arno

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Hi,

I don't fully understand your math up there, but less materials and textures gives less drawcalls. So in general that's best for performance.
 
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