ZDoom

Sorry if this error has already been discovered.

I was playing Infinity (http://www.doomworld.com/idgames/index.php?id=2016) today with ScoreDoom, which seems to use an older, modified version of GZDoom as its base. I was in E1M4, in the area near the red key. There's a section right next to the red key where there is a very thin gap in the wall (sector 202: 16 units wide, 128 units tall). I approached from the north side, walked forward (south), up against the gap, and fell partway through the floor. Enemies could still see me and attempted to fire at me, but seemed unable to hit me. I could move left and right (east and west) but was otherwise unable to go anywhere, and eventually I had to turn clipping off to escape.

I also tested this on GZDoom 1.5.06 and had the same issue.

I then tried it with ZDoom 2.5.0 (compatflags = 128; dmflags = 4521984; dmflags2 = 0) and encountered the same issue.

I was able to duplicate this bug several times. Strangely, approaching the same sector from the southern side did not cause a problem.

This effect does not seem to occur in vanilla DOOM or Chocolate Doom.

Several of these old WADs have buggy nodes. The reason that the other source ports are not affected is that they also contain a bug in their node checking code which cancels the bug in the node builder.

ZDoom's checking code does not have that bug and for technical reasons it's not advisable to reactivate it.

You can verify if this is the case by setting 'gennodes 1' at the console before starting the map. If that works it is a node problem.

Ah, yes, gennodes fixed it. I figured this was probably already known, but I thought I might as well report it, just in case. Thank you!