This page explains how to load 3D models and other enhancements using command line options (in Linux).
Assuming Doomsday (deng) is installed in /usr/local/share/deng, and my WAD files in ~/wads/, do the following:
So, the command line that does the job could be:
Note: The “}” is really that way.
There is a related question in the FAQ: “How can I play without KickStart?”.