Brian's Pages: Orbiter Addon Help

Apologies to JFK, but Orbiter addons aren't that hard, actually!

Here's some of the tools I've found useful and/or utterly needed, presented more or less in the order you'll be using them to get your dream project into Orbiter. I'm not any sort of expert, having only started Orbiter addons this summer, and I'm sure other people have different suites of programs they use, but this batch works for me. The big plus is that all of these excellent programs are freeware. (with the exception of Photoshop, which I already owned...)

Tip One: Read The Fine Manuals!

The Orbiter manuals are generally very well done, and there's a great amount of information in them, especially Orbiter.pdf, the main Orbiter manual. The whole of Section 16 concerns config files and addons. RTFM applies just as much to whatever programs you're using for addons, too! Anim8or has a decent manual, and most of these programs, except for the very simplest, have documentation of some sort!

Programs I've found useful:

The Orbiter SDK: More information than is included in the main Orbiter manual, and several needed utilities. DXtex is the one you'll use most often if you're texturing anything. Freeware (obviously).
Anim8or: For mesh creation and general 3d modelling. Freeware. Blender is also highly regarded & freeware, but seems harder to use than Anim8or. If you own Flight Simulator 2002 Professional or FS 2004 (FS9), it ships with GMAX, for which there are freeware GMAX-to-msh converters available at Avsim's Library.
Vinka's 3ds2msh converter: Export your models in 3ds format from Anim8or, and use this command-line converter to get them into Orbiter's msh format. You do need to be somewhat familiar with DOS command-line entry to work this utility, but it's fairly straightforward. Freeware.
UVMapper: Used to build texture maps from .obj mesh files, which you also export from Anim8or. Freeware. There is also the non-freeware Ultimate Unwrap3D, which looks very good.
TerraGen: If you're doing scenery meshes, as opposed to only buildings, this is the program you want! Can export meshes in formats Anim8or can read, and you can import .raw or .bmp graphics as heightmaps. Freeware.
You'll also need a decent paint program, if you're doing any texturing. I've got Adobe Photoshop 6, which is decidedly NOT free, but excellent. The GIMP is the freeware equivalent of Photoshop.
If you use Adobe Photoshop for texture creation, there's a DDS file format plugin from Nvidia that lets you load, view and save .dds format images directly in Photoshop & Paint Shop Pro. Freeware plugin. Changed!
Meshes, textures, tutorials & other information on 3d modelling can be found at 3D Cafe, 3d Scene, or DMOZ's Open Directory: 3d Rendering & Modelling.

You're going to spend a lot of time flipping back and forth between formats - most of my projects have at least three or four files. 'Lowell' has more than twenty!! For example, Orbiter uses .dds format for it's textures, while Anim8or won't read dds, so you'll have to have bmp, gif or jpg versions of your textures as well.

As another example, see my Orbiter Mars Addons page. There, my mesh files started out as .raw greyscale images from Photoshop; imported into Terragen these raw files became a 3d heightmap, which was exported as a Lightwave (lwo) mesh from Terragen. Anim8or imported that lwo file, which I saved as an Anim8or-native an8 file and cut up into several smaller, exported 3ds files. Vinka's converter took these 3ds files and turned them into Orbiter's own .msh format. That's a lot of steps, and a lot of working files! (Fortunately, none of them are huge. The largest file to come out of this was only 1.6Mg or so.)

Finally, and perhaps most valuable of all, the Orbiter Forums are full of talented people who collectively know masses of stuff about Orbiter, 3d work, and all sorts of related issues. PLEASE see my Tip One about reading the actual manual before you post to the Forums, though! A number of people there (myself included) aren't shy about telling people to go Read The Freaking Manual!

A (few) Frequently Asked Questions About Add-ons:

One: How do I make my great idea into an actual Orbiter addon?

Start with the manuals that Orbiter comes with. The basic Orbiter.pdf manual has an entire section that explains the various configuration file (.cfg) entries in most of the detail you'll need. See Section 16, pg. 45-53. The Orbiter Software Developer's Kit (SDK) has another pair of manuals; 3dModel.pdf is the most useful for someone just starting, especially if you're building a new spacecraft. Section 2 of that manual lays out, in order, what you need to do to get your spacecraft into Orbiter!

The manuals are in Orbiter's Doc sub-directory; the SDK's are in that directory's Doc sub-directory.

Two: Do I need to know C++ programming to build my Orbiter addon?

Not really! The simplest addons - basic surface bases - can be done with nothing more than typing in a config file! My own Rhea Base is done this way. For stations or basic ships, you'll need a mesh from a 3d program, plus a fairly simple config file. If you want more complex ships you're into C++ territory - but even there, the modules that Vinka has been producing are making that easier as well!

Three: How do I build meshes for custom objects in Orbiter?

You'll need a 3-d modelling program of some sort, first. I use the freeware Anim8or ; the commercial 3dsMax is expensive but apparently very good. There are several other freeware modelling programs available as well. I'll try and add links to them as I find them. Anim8or is good, though.

If you have Flight Simulator 2002 Professional or FS2004 (FS9), these two programs ship with GMAX. There are several GMAX-to-msh converters available on Avsim's Library. (Changed! - note that Avsim's new Library policy means that you have to be logged in before you can access files there. Registration is free and simple, though, and well worth it.)

After you've got a good looking object in whatever program you've used, save or export it in 3ds format, and use Vinka's 3ds2msh converter to create a format Orbiter will recognise.

Four: Wait, how do I use this 3ds2msh thing? It's a wierd program!

Actually, it's easier than it looks. The thing that makes it look wierd is that it's a DOS-based command line program, so instead of clicking and dragging or whatever in Windows, you just type a line of text at a DOS prompt, and that tells 3ds2msh what to do.

Start by bringing up a DOS prompt - in Windows 98se, go Start-Run, and type 'command' (with no quotes) in the box. That'll bring up a DOS prompt window. Open Windows Explorer to the directory you've got 3ds2msh and your 3ds file in before you go Start-Run, and the prompt will already be set to the correct directory/sub-directory for you. Then type '3ds2msh' (no quotes again) to get a short list of all the commands available in 3ds2msh.

As always, READ THE MANUAL! In this case, 3ds2msh comes with "3ds2msh_readme.txt" which contains enough to get you started. Just remember that it's still a DOS-based program and not a Windows-based one! (I admit that I had to do a fast bit of re-learning DOS stuff when first confronted with 3ds2msh! It's pretty simple, though)

Five: Can I use GMAX for building Orbiter meshes?

Yes, you can. There are several GMAX-to-msh converters on Avsim. See the link above.

I'll be adding to this FAQ as questions and information come up on the Orbiter Forums or is sent to me! In the mean time, allow me to close with

Tip One: Read The Fine Manuals!

Have fun adding stuff to the Orbiter universe!