Coop spawn off the map clientside
Created attachment 272 [details]
Screenshot showing player's spawn location of DOOM2 MAP02
On coop server running doom2.wad and no pwads, d1337r's client would appear to spawn him outside the map boundaries. However he would appear to other players as having spawned in the normal place at the start of the map. He did not have this problem with either doom.wad or servers using pwads. Attached screenshots shows the md5-hash of doom2.wad is correct. He is running Debian on AMD64.
Created attachment 273 [details]
Screenshot showing player's doom2.wad hash
A comment: I keep spawning to the southwest of the actual MAP02. The players, monsters and pickups seem to be messed up, too. If I'm in the spectator mode, I can go anywhere, except inside the actual map. The problem also doesn't show if I connect to a server running any other IWAD (like freedoom) or if I play the game offline.
The server at 184.108.40.206:10667 (ENZ Doom2 Coop) seems to work fine on MAP05. CoffeeNet MWI1: Doom 2 Co-Op (220.127.116.11:10703) also works with MAP03.
18.104.22.168:14001 worked with MAP11.
Running and connecting to a local server works fine, too.
Now that's strange. I redownloaded doom2.wad, now it works everywhere, but the question arises: why BOTH wads worked? Did they suddenly have the same hash? Or Odamex knows about several valid hashes (guess one of them is not so valid now) for doom2.wad?
Created attachment 275 [details]
The proper doom2.wad
Here is the screenshot with a different doom2.wad. It works!
Perhaps clients with IWADS that do not match the server's IWAD checksum should be kicked, both to prevent cheating and to prevent confusion when the game behavior is incorrect due to IWAD differences. The server already kicks clients who have a different version of the Odamex client than the server expects.
The information is this bug led to bug 720.
Closing as this is not actually a bug. However, the issue of poor handling of client IWAD checksums will be addressed with bug 720.