ZDoom

Edit: As you see, I use two different textures for the locker: one has a stain, and the other doesn't. The stain now is a layer in Photoshop. How do I use layered textures correctly: a) prepare two large textures in a graphical software or b) make layers in UDM? If the latter, how do I create a ...

Should they be a power of two (128, 256, 512)?

The less 1's the binary number has, the faster the computer processes it, so yes, they should.

These are called "3D Floors" in UDMF (https://zdoom.org/wiki/Sector_Set3dFloor)

https://store.steampowered.com/app/1356040/Ampersat/
Until July 6.

https://store.steampowered.com/app/6246 ... p_Tactics/
Until July 1.

https://store.steampowered.com/app/2524 ... World_Dig/
Until June 26.

https://store.steampowered.com/app/4317 ... ilon_Indi/
Until June 26.

https://store.steampowered.com/app/610570/Paradox_Soul/
Until June 17.

https://store.steampowered.com/app/2752 ... T_THE_PAK/
Until June 24

Sorry again but https://store.steampowered.com/app/2928 ... ash_Cards/
Until June 9

https://store.steampowered.com/app/49520/Borderlands_2/
Until June 8.

https://store.steampowered.com/app/3345 ... _Sapienza/
Edit:
Sorry but also https://store.steampowered.com/app/3345 ... _Sapienza/ (until June 2)

Also https://store.steampowered.com/app/4896 ... cs_of_War/
Until May 29

https://store.steampowered.com/app/3032020/Cast__Spell/
Until May 20

1. Extract tiles*.art files and palette.dat file from amctc*.grp files (if not extracted already) using Slade
2. Extract sprites from tiles*.art files using https://m210.duke4.net/index.php/downlo ... les-editor