by motorsep » Fri Jun 20, 2014 9:07 pm
Let me dime into this thread.
DP's collisions will fail after ~32k units radius around 0 0 0 of the map. LH committed a few things for collisions recently, but I don't know if that changed anything. I haven't tested collisions on flat brushes passed 32k, but I did test brush based terrain and mesh collisions - both fails on non-flat floor (terrain).
idTech 4 can not handle high poly scenes. You would need to modify rendering code to make that possible (not much modifications though). Collision system there is different, so when compiled 32bit on Windows with x87 FPU, collisions work fine on terrains up to 130k x 130k. Megatextures work, and there was a tutorial on how to make it better, higher quality on D3W, but D3W is gone now, and there is no Megatexture authoring tool one can use for commercial project (there is one editor, somewhere, that was made by the same guy who made megatexture tools for ETQW).
Networking code in idTech 4 is horrible.
Doom 3 BFG is not moddable out of the box. Even if you grab RBDoom 3 BFG forks, it's still not moddable easily. Storm Engine 2 fork is moddable, but it took us blood, sweat and tears to make it into good solid engine. And it's not publicly available yet. Doom 3 BFG has no megatextures, because those were from RAGE and were removed for GPL release.
Networking code in Doom 3 BFG is superb (at ping 400 it felt like playing on LAN), but I haven't tested it with 3+ players. So with 64 players it might not work well.
Funny thing - it's hard to find 8 people to play online (and I am not talking about CoD or BF games), and you want 64 people. Also, you'd need a fat channel for your server, and powerful CPU.
Another thing to note is that you'd need to fill the map with some content, and you would need LOD system for that content.