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One of the more important events that encouraged a lot of us to begin building models for MSTS was the release of the gmax gamepack. As you probably know, gmax is a stripped down version of 3dsMax 4. But unlike 3dsMax, gmax was available as a free download.
If you used gmax to create your MSTS models, you probably discovered at some point that your MSTS gmax files aren't of much use for anything other than making MSTS shape files. You can't export them to any other program, not even to 3dsMax itself. So what to do with all those great models you built?
Have no fear. There's a way out of this dilemma. Actually there are several of them, all of which involve a two-step conversion process. I've found the one described here to be relatively painless.
You'll need to download a couple of items. The first is the Tempest (Quake III) gamepack for gmax. It's available at no cost from the TurboSquid site, which is where you may have downloaded gmax itself. Here's the link. The Tempest gamepack will install itself in the gmax gamepacks folder, alongside the MSTS gamepack.
The other item you'll need is a product called MilkShape 3D. MilkShape is the brainchild of Mete Ciragan, who lives in Helsinki. MilkShape is actually a quite capable modeling program by itself, and it's used to create objects and characters for many different games. Our interest here is in its ability to import and export 3D models in a wide variety of modeling file formats. Download MilkShape here. Once installed, the program will be fully functional for 30 days on a trial basis. After that you'll have to buy a license. The current price is $35 or €25.
Before you start the conversion process, you might want to delete all but the nearest LOD level of your gmax MSTS model and save it under a different file name. You don't have to do this, but eventually you'll have to rename the duplicate nodes and there's no sure way to know which instance of a node name goes with which LOD. It's likely you'll be upgrading your model for TS2 and you'll want to rebuild the far-field LODs anyway.
OK, let's start converting. The Tempest gamepack install places a shortcut in the Tempest folder. Use this shortcut to launch gmax. (As with the MSTS gamepack, you don't want to launch gmax.exe directly.) The first thing you'll see is this dialog:
Unless you have Quake on your system, click No.
Open your model file. (It should be mentioned that we're talking about files with the .gmax extension, not the MSTS shape files with the .s extension.) This dialog appears:
Unsupported objects? That sounds ominous, but it really isn't. Just click Open. You can decide if you want to check the Don't display this message box or not.
Your model should now appear in gmax, but without any textures. That's OK - the UV mapping coordinates will be preserved throughout the conversion process. You'll have to convert the textures for RailWorks anyway.
Now we'll export the model from gmax in MD3 format. Click File/Export in the menu. Specify a file name and in the Save as type: list box, select Quake III (*.MD3) as shown below.
Now you'll get another dialog. Enter the number 1 where it says The Following Frames:, as shown here.
Click Export Now. Yet another dialog will appear:
Just click OK. You may have to do that several times. Your model has now been saved in MD3 format.
MilkShape is used for the final conversion. Launch MilkShape. From the menu, choose File/Import/Quake III Arena MD3.... A standard Open File dialog appears. Locate your new MD3 file and open it. Your model should now be displayed in MilkShape.
Now we'll do the final export. From the menu choose File/Export/Autodesk 3DS. You can choose one of the other export formats if you want, but most modeling programs can read 3DS format. An Export dialog will appear. Enter a file name and hit the Save button.
At this point the 3DS file is ready to be imported into your preferred modeling program. You may have to rotate the mesh around one or two of the coordinate axes in order to position your model in the proper orientation.