Some FSX only airports like Imagine Sim's VIDP perform poorly in P3D. Ideally the developer has to release a P3D version, but until that happens, there is a solution. I chanced upon this when I saw a solution to missing objects/buildings in P3D vs FSX as reference (e.g. Thai Creation Mumbai). 

 

Looks like there is difference in the BGL format for P3D vs FSX, this difference sometime causes invisible buildings or performance problems. 

 

The solution is to covert these BGLs to P3D format using ModelConvertorX. Step by step instructions on how convert a BGL are here - http://www.iflysimx.com/topic/1004-cuba-in-p3d-v23/. If I understood correctly, then you only have to convert library BGLs (vs placement BGLs). So the basic idea is to convert the BGLs in your Airport's scenery folder. Adventurous folks can use the batch mode to convert all/multiple files.

 

I used the batch mode to convert VIDP and the result was that in the reference scene I was using to compare FPS, the FPS went from 10-12 to 22-23, almost 100% increase. Of course the actual result will vary for different airports, and in some cases you main gain nothing at all. 

 

Note that in the VIDP conversion, I was missing Jetways after conversion, so I restored only the jetway BGLs back to original FSX BGLs. So If you get missing objects you may have restore those BGLs.

 

Overall, it is not completely straight-forward but the reward is worth it. For me, VIDP was un-usable before this, now its like any other airport.

 

Lastly, I wonder if this can be used to improve performance for some Airports which support both FSX and P3D together. Maybe the developer keeps the BGLs in FSX format for dual compatibility and we can gain by converting?

Yes I have been using this reformatting of BGLs to get objects to appear in P3D for a wee while.

I was jsut wondering how you batch covert multiple BGL'S. I normally import the BGL and then use the 'export Scenery' option.

The batch wizard does not seem to allow for this configuration. What do you use? It would certainly save time.

 

EDIT.  Aha I found the answer. The radio check buttons on the bottom.