I am super interested in hearing all about the technical process behind building and using 3D indoor environments for your engines/games. What software do you use? How do you approach importing the maps? How do you handle large maps? Do you use a skybox/equivalent? Do you use a specific shader for the interior? Do you have any screenshots of an indoor environment that you designed? Anything you're willing to share would be awesome!
Backstory - I have spent a lot of time trying to build my first 3D renderer, I would love to design a simple Doom-like map to put it to the test and need some inspiration/direction.