One Minute Game Review by The Happy Friar:
Also on Rumble:

idTech 4 (aka Doom 3 tech) Discord Server!

Main Menu

Collision for Static Model

Started by select, January 23, 2019, 05:32:16 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.



I've picked up working on my doom3 mod since 5 years.. so i've gotten a bit rusty. Glad i've found this forum though. Very unfortunate what happened to D3W though :-[

Anyway, i have a custom model which i need a simpler collision model for. I've checked the game files and theres .cm files for various moveable objects.
As far as i remember you had to create a brush inside the Radiant and could export it as .cm file. But everytime i try that, it doesn't do anything.

Hope anyone can help me. Thanks.

The Happy Friar

just tried.  i made a cube, applied the collision texture, then selection - export - to CM.  Did't seem to matter what model format I chose, always saved as a .cm.  I had to save in to my doom 3 folder for it to save & if it added .cm for me.  opening the file they were collision model files, not ASE or LWO files.
I could export a .OBJ to my desktop but not a cm file. 


Thank you.. exporting it to the doom3 folder worked. Interesting, that it doesnt work outside the base path.

Unfortunately i've ran into the next issue, i have an .ASE as static model and want to use it as a moveable. Therefore i need a simpler model for collision.
I've looked into the moveables .def file but i think the models from id come with a collision model built in?

Thank you for your help

The Happy Friar

a quick looks leaves me clueless how they're used, but i remember using them before.  I'll have to experiment with some.


Thank you.. your help is much appreciated.

If you open one of ids .cm files it has a header which points to the model file. Not sure if that does anything though.


You can use Dark Radiant to create cm models.

And I believe you're correct, some Id models have the collision model in the original source.


Thank you very much, that did the trick. It needs to be a func_clipmodel before exporting and also it must consist of only one brush afaik.


I make collison models in a modeling suite. First I make a first body (my complete model), then I make another body and after UV Mapping I assign collision texture to it. Next I hide the second body inside the first one and write all the Def stuff.