Material Files
Originally written by Fingernail & greebo on http://forums.thedarkmod.com/topic/127
What the Heck is a Material File?
The material files (extension .mtr) contain lists of 'material definitions' that tell the engine where to find the source files for the specified textures and what features it should have. All material files should be located in the darkmod/materials folder.
Material definitions apply to a single 'texture', though it may be made up of multiple texture files blended together. A simple material definition looks like this:
textures/darkmod/custom/wall1 { qer_editorimage textures/darkmod/custom/wall1_ed diffusemap textures/darkmod/custom/wall1_d normalmap textures/darkmod/custom/wall1_local specularmap textures/darkmod/custom/wall1_s }
If you're using the texture called textures/darkmod/custom/wall1 in your map, Doom looks up the name in the material definition and loads the according files. Note that you don't need to specify the file extension, the engine is automatically adding it (depending on your quality setting) and finds the according texture file.
A single material file contains lots of material definitions. This is useful as textures that logically belong to each other (e.g. several wall textures) can be summarized in one material file (e.g. materials/darkmod_walls.mtr)
The .mtr files are read upon launching Doom 3 - changing your material file therefore requires restarting Doom.
Create a new Texture Definition
Provided you already saved your texture source file (the .tga or .dds) in the appropriate folder, you can go on and create your texture definition. You cannot use your textures without this step.
Open up or create your personal material file with a text editor. There are existing guidelines for where texture definitions should go, for the sake of organization, but the engine doesn't care what the filename is as long as it's in the materials folder and has a .mtr extension.
First, specify the name of your new material. If it is not a model texture, then the name should include the path to the texture files used. Example:
textures/darkmod/stone/brick/redbrick_wall1
Then, open up a squiggly bracket ({), and start to fill in the texture paths as below, changing the paths and names for your texture.
textures/darkmod/stone/brick/redbrick_wall1 { qer_editorimage textures/darkmod/stone/brick/redbrick_wall1_ed //editor image diffusemap textures/darkmod/stone/brick/redbrick_d //diffuse map normalmap textures/darkmod/stone/brick/redbrick_local //normal map specularmap textures/darkmod/stone/brick/redbrick_s //specular map }
Close the definition with a close squiggly bracket (}).
Save the file. Now you can load your new texture in DoomEdit or DarkRadiant provided you did it all correctly.
Alternatively you can also have a look a the existing material files and learn from them.