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Extract from libraries

I am trying to convert some old FS9 sceneries to FSX/P3D. I have some of the models as separate files - no problem with those. But some models are in a library file and MCX can not access them. Is there any way to extract models from a library?

Some FS9 scenery libraries utilize SCASM-compiled 3D models (not in MDL format) with conditional display code.

Depending on the individual 3D model and the conditional display code context, one may be able to still convert after de-compiling to *.SCA source code, editing, then importing the edited *.SCA file into MCX.

Tell us more about the BGL file(s) and whether they are payware or freeware, and we may be able to advise you further as to your options for conversion for use (only) on your own computer.

The bgl files are files from my own earlier scenery projects and projects I have contributed models to. Some models were made by other members of the Finnish Scenery Designers (FISD) and included as libraries in our various projects. Don't know if they are SCASM-compiled, how can I find out? I am trying to re-create some of our sceneries as FSX/P3D versions. All freeware.
What happens when you import these libraries into MCX? Can we get an example of one of these?
I get the error message
BGL9Reader Error This BGL file is compressed and can not be read.

One file attached


  • trees.bgl
    1.8 KB · Views: 261
Unfortunately it appears you have indeed compressed the file. I tried several decompilers and they all report the file is not readable. This is great to avoid pirates, but keeping a copy of the uncompressed file becomes important at that point...
Ok, thanks anyway for your help! Then I know. I have to try to find the original author and hope he still has the originals. Or make new models...
I don't think there is any decompressor for compressed bgl files. I never found one. Luckily not that many files are compressed.
I ran, from a command prompt
bglzip -d -f trees.bgl

Only placement info in this file according to MCX.
Disassembling with BGLAnalyze31 doesn't seem to achieve anything extra.


  • trees.bgl
    12.9 KB · Views: 199
  • treesBglA31a.sca.txt
    72.4 KB · Views: 213
  • treesBglA31b.sca.txt
    74 KB · Views: 218

Indeed as Essex states above, there is a legacy FS2000 - 2002 SDK de-compressor in the "BGLZIP" SDK component

IIUC, this is a FS2000 / FS2002-era SCASM compiled BGL which can be automatically de-compiled by BGLAnalyze version 3.1, and contains legacy format' Library-type' object placement info for 40 trees in the vicinity of Turku airport in Finland.

Chances are that such trees in the called legacy format "Library" are older uni-planar 'rotate-to-camera' tree types which, IMHO, are best replaced by FSX / P3D format, default or custom 'crossed-plane' trees placed with BGLComp-type XML 3D scenery tree objects.

The Geographic coordinates in the 40 placement RefPoints might be used as a guide for placement info. :idea:



  • trees.sca.zip
    8.9 KB · Views: 156
Ok, fine, thanks. I already found the trees - they are in a separately installed common FISD library (and all cross-plane). But looking closer at my project it turned out that parts of the airport have changed so much that I have to place trees and stuff from scratch anyway. So there is no use for the old placement info...