I've been working on a project I call "Doom Evil 4" for a while now... Actually, I've been working on it since September 22, 2017, so a little longer than a while, but still, the point is, I've been working on it for quite some time. There's custom guns that I got frames directly from the game to develop like the iconic Red 9, Handgun, Knife, the Shotgun, and even the Chicago Typewriter, some custom Midi tracks (although, they're short and have weird instruments, but for a free website that actually works, I don't think I'm in the right to complain about the instruments of the Midis), a custom player class (you spawn with Leon's Knife and the Handgun instead of the Fist and Pistol items that you normally spawn with in Doom and Doom II), a custom enemy (although, it's just the ShotgunGuy class dropping 5 shotgun shells rather than a shotgun), a custom set of healing items (Green Herb that heals 50 HP, a Red Herb that heals 200 HP, and a Yellow Herb that adds 1 to your maximum replenishable health), and a custom texture (this is a night sky for the dark levels that seem to be obscenely dark in GZDoom compared to Zandronum). This is a pretty massive project, remaking all of Resident Evil 4 in every respect, but I know that if a team of people work on it, it can get a done a lot better (and faster) than just me. The levels have no form of 3D effects in the means of map design (besides some tricks I pulled off to give that illusion), some stuff is just... wrong (like doors for example), and well, the enemies are still Doom II enemies... So, that's something that needs to change.
The main problem I'm having is the fact that whenever the Wad becomes compatible with GZDoom, it's no longer compatible with anything else. If it's compatible with Zandronum, nothing else is compatible (or something big breaks). I guess there's things that each engine can support that others can't, but it is kinda ridiculous. Another problem I'm having with it is the fact that I have no access to the meshes of RE4, so I can't pose everything in say, Unity for example, and get every frame I need from there for guns. And of course, we can't forget the ever classic, I can only seem to make stuff in the "classic" Doom style. As in, I don't know how to make 3D sectors. If anyone wants to help, just post here. Also, if anyone wants to do a 3D version, as in, all the enemies/items/gun sprites are fully 3D like the map, I have no idea how to make 3D meshes and stuff like that, so that'd have to be someone else's job, as long as everything resembles the original game.
For anyone that wants to see footage of the mod, here's a video of me playing the GZDoom version after having reconfigured the code of the Wad. The lighting is darker than it was in Zandronum, and I didn't account for that, but this is most of what I've gotten done so far.