Simviation Forums

Hello, I tried to use PPE (Pretty Poly Editor) to load an MDL file, so I could save it to a format that GMAX could use, however; PPE only displays a garbled model of the airplane, and it saves a garbled one too, so I was wondering.... How can I import\convert FS2002 MDL files into a format that GMAX can use?

as far as i know i dont think that it is possible to do "reverse engineering" although if here is i'd love to know about it

How do people edit other peoples aircraft then? Is there no way to open an MDL file in another 3D viewer like PPE that can save to other formats?

"Editing" other people's models is a touchy subject.

If by "editing" you mean repainting, then that's just opening textures and working with them.

If by "editing" you mean affecting the flight dynamics - giving it better/more accurate performance, that involvesworking with just the aircraft.cfg and *.air files, both of which can be changed with a text editor (aircraf.cfg) or a freeware utility for thej *.air file- (AirEd, for example)

If by "editing" you mean changing the model's visual appearance, removing/adding  a second pilot, changing the visual so it resembles a different variant (i.e. a Spit 9 from a normal Malcol hood to a cutback bubble canopy), then you're getting into a very touchy area.

There are utilities that can convert an older style MDL file (pre-gmax, FSDS2) to a 3D model that can be opened in gmax, FSDS, etc.  However, you end up having to rename, reanimate, retag, retexture the model, apart from having to respawn the model.  There is so much work to be done that if you can handle gmax/FSDS, you're better off building the model from scratch.  In this case, you're better off looking for a similar source file and working from it.  Sometimes the original builder will gladly provide the source file if you propose the change(s) you plan to do, and of course, give proper credit.

How do people edit other peoples aircraft then? Is there no way to open an MDL file in another 3D viewer like PPE that can save to other formats?

I'd like to add to Felix's comments, that every designer I've ever contacted has been most generous in giving support for my projects, so don't be put off in having to contact original designers to get source files. It's amazing how far saying please and thank you can get you, even today. It's one of the things that makes this group like a community. And like all communities, there is a code of conduct. High on the list - give credit where credit is due.

PPE supports the old dll MDL format from FS95/FS98/FS2K. It searches the file for the geometry section, begun with two specific hexidecimal opcodes. If your FS2K4 model happened to have these opcodes you'd probably get garbage as the new FS2K2/FS2K4 MDL format (MS RIFF) has the actual word "BGL" within the file to denote the start of the geometry section.

I've been searching for a sample parser for the new FS2K2/FS2K4 RIFF MDL format, which is published on MS FS2002 SDK site. I've been able open up and parse part of the file but the documentation isn't accurate and the trial and error crap is getting old. Does anyone know or is aware of a software developer that is able to parse the new MDL format?

gMax only directly reads gmax and max files. Fortunately, it's able to import several file types, the best of which I have experience with would probably be the Wavefront OBJ format. It's a public format and is not as nasty to use as AutoCAD DXF. Discreet documents this in their help file, on their website, and support site. Hence, a converter from MDL to Alias Wavefront OBJ would work for the basics. However, much MDL specific data would be lost. I'm not an experienced modeller (at least not in the PC arena) and don't know know what loss would be acceptable nor the process to get around that step (e.g., only model the basic geometry then add the specifics at the end?).

So, if anybody has accurate info on the new RIFF MDL format I'm all ears.

Bob Buckley
Colorado Springs

I have no doubt that it's possible - Abacus' FS Painter reads the MDL and texture assignments for FS2002 and FS2004, including the default aircraft, but it does NOT change any model or texture names, etc.

However, editing from the MDL is a VERY touchy subject, not the least because of the possibility of some unscrupulus fellow editing someone else's work and passing it off as their own, opening a commercial product - inlcuding the default models, and passing it off (I've seen some default CFS2 models uploaded to sites with repainted textures).

Chances are, if a modeller doesn't release the source file, either publicly, or upon request, he/she doesn't want anyone else to modify it.

At any event, you still end up having to remap and reanimate everything

I wish that there is a simple tool that can allow us can import a *.mdl file to a gmax file (*.scn). However, that MIGHT cause some problems when it comes to credibility for someone. But don't get me started on that.

There is a simulator I like, somewhat. It's Orbiter Space Flight Simulator. You can find it at http://www.medphys.ucl.ac.uk/~martins/orbit/orbit.html

The simulator uses a so-called *.msh file (mesh) that can be used to display the visual model in the sim. The *.msh file can be imported to a gmax format (you need a script file to do this from gmax) so that you can edit it.

A *.msh file a pretty much like a space sim counterpart to the *.mdl file that we know.

Drawbacks: You may by able to import a mesh file to a gmax file, but exporting it back to a mesh file is a mission. In fact, you are probably required to know a little bit about C++ programming. Not only that, if you plan to release the edited mesh through the web for others to use, then you need serious permission from the original authors.