Model Editing by Shoaib Kamil

Editing the MDLs or creating new ones is pretty complicated. Before we get into editing them, let's find out a bit more about MDL files. An MDL file is divided into two parts: the 3D info, and the skin. The 3D info is a wireframe model, and the skin is a 2-dimensional BMP that is painted onto the wireframe. Every frame has a new set of 3D data, but you only need one skin. You can edit a skin without changing the 3D data, and vice-versa.

Confused? Don't worry. Look at the pictures that follow.

This is the skin. Basically, it is one image, composed of two parts: one part for the front, and the other for the back of the MDL.
The 3D data is a set of polygons. Every frame has a different model, all contained in an MDL file. You don't need to have much detail in an MDL; use a skin for the detail (like the muscles).
The finished product. It is the skin painted on top of the 3-D model.

Clear now?

So how can you make your own? Well, you should use Autodesk's 3D Studio or Alias, two high-end programs costing thousands of dollars. Or you could use Breeze Designer 2.0...which is shareware. To manipulate MDL files, use MedDLe. To create new skins, use any paint program that can read/write BMP files.

Let's start with simply editing the way the soldier looks. Using MedDLe or QuakeME, extract a blank skin from the '/quake/id1/progs/soldier.mdl' file. (You did unpack the PAK0.PAK file, right?). Load it up in a good graphics editor that can read BMP files. The first thing you'll notice is that there are two parts, one for the front and one for the back. Go ahead and make something simple:arms, legs, and a gun. Now tell your MDL program to import your new skin, and wa-la! Instant new look.

Yeah, but the 3-D...
So you want to play with the big boys, huh? Manipulating the 3-D data is a job best done by the serious Quaker. The only time you need to manipulate the 3-D is if you want to give the MDL a totally new look. A new shape, so to speak.

The 3-D data changes for every frame. So if you want to give the soldier (or any other MDL) a new set of 3-D data, you have to replace every frame. If you're replacing 3-D data, the new data must have the same number of vertices as the old. But if you're making a MDL from scratch, you can have any number of vertices. Every frame in an MDL must have the same number of vertices.

So let's start. First, using MedDLe, extract the 3-D data from the MDL. Then load it up into AutoCAD, 3dStudio, or Breeze Designer. Fiddle around with it as much as you want, and save. Do this for EVERY FRAME!!! Then import all the frames back into the MDL file. That's all there is to it.

So how do you make your MDL's movements look lifelike? Every frame should be the previous one, with a few vertices moved. With effort, you can produce an MDL that rivals id's. In fact, I changed the 'spike.mdl' to look more like a nail when it comes out of the nailgun. Very simple to do.

This description was part of the Quake Editing page maintained by Shoaib Kamil.