BRASS 'n' BLOOD 1.0 Blood decals, bullethole decals, and spent shell casings hang around 'practically forever.'
PERFORMANCE BE DAMNED! (it's a DooM pun)
BRASS 'n' BLOOD combines two existing mods for Doom3, to make blood & bullethole decals and spent shell casings hang around for many hours, instead of vanishing within moments. Much more immersive. Credit to the original mod authors, Boglito and Burning Fish created the mods this is based on.
Someone else already "combined" them, but did a sloppy job (no shade, they were probably just in a hurry). I corrected a mistake, added a small common tweak (reduce shotgun spread, since that value exists in one of the files touched by this mod), created some documentation, and packaged everything neatly. Please see the README for more info.