Because there is strong demand for a simple tutorial, I decided to write a simpler prop export tutorial. This tutorial needs basic knowledge of 3ds Max 2009.
Posted by Attila1945 on Jun 18th, 2012
Basic Props Modelling.
First, what do we need to start the exporting? Well, the answer is simple. The model, a volume for hit detection, it always have _vol postfix , the basis is for a global position reference in-game. (1st picture)
Its proper buildup is the following: the basis must be at 0;0;0; coordinates, then the main model should be centered to the basis, and the volume must cover the model, for proper hit detection. For easier understand, we usually change it to see it as a box only. You can do it by click on the volume with left mouse button, choose the object properties sub menu, then check the "display as Box" option. Here you can add the exporting parameters too in the "User Defined" text-box.
The next step is to give the proper exporting parameters. I wrote easy examples on the second picture.
The next thing to do is the proper linking. Linking is important, because the engine must know which parts move together example when its fall away. Every basic model goes to the basis, but if a model has a separated part, a wing on a plane example, the wing is must to be linked to the fuselage. The proper name of the most basic model is always called body. The _vols must be linked to their part, what they made for. Example, a wheels volume must be linked to its wheel. The linking method is looks like this: first, you select what you want to link, then hold right mouse button while you point to where you want to link it. The models are usually flashes for a second after a successfully linking. If you ready, you can check the linking tree if you click to "Select by name" button. ( 3rd picture)
When everything OK, you have to export it to .mdl format. You have choose the export function in the "File" menu, then select the .mdl as a format. As a name, you can write everything here, it does not count. The exporter using the exporter parameter in the basis for giving a name. The exporting menu shows up, you just have to click on export. The most of the error messages can be ignored like "the volume is isn't convex" , or "the mesh is not original scale".
If the files are ready, they need some post editing. The .def file is never proper, and always crash the game. To fix this, load it to a notepad. I recommend Notepad++, because its much more advanced and faster than the original one. When you opened, simply delete the old, bad information, but copy the .mdl file name. Paste an other props definition file here, just change the .mdl file name, or you can use my example, this is more than enough for a basic prop.
The option prop is means the material of the props, its means what is made of. You can write here concrete, wood, or steel too. Check other .defs for good examples too, and experiment the best option for you. If everything OK now, copy your creation to the entity dir of your mod, and then you can use it.
To not be this a dead letter, here is the box in-game to made it believable.
I hope I helped somebody, who wanted to learn a little about this topic.