MAP04's invisible wall in Realm of Chaos

[Rudolph]

So in preparation for Cammy's 25th anniversary re-release of Realm of Chaos, I have decided to give the original mapset a shot, only to hit a literal (invisible) wall in MAP04. Seriously, I cannot get past the corridor shown in the screenshots below.

 

[galileo31dos01]

Seems fine on my end, I don't hit any invisible barriers in that corridor. There is a linedef on the medikit, for the midtex moss, but it's not flagged impassable or anything special, so not sure why you are experiencing that problem. What port are you using? and... do you have "RlmChaos.wad" right? although I'm not sure if there's another version laying around.

[Rudolph]

I downloaded the mapset from the link provided on the Doom wiki page.

 

I use GZDoom 4.7.1.

[HackNeyed]

Hmm, using GZDoom (even with compatibility options), Eternity, Woof or DSDA-Doom v0.22 with complevel 21 (MBF21) that vine is impassable.

 

Woof / DSDA-Doom with a complevel of 11 or below, Eternity with the -vanilla command as well as LZDoom 3.88a and ZDoom 2.8.1 work fine.

 

EDIT: Tested more engines.

EDIT2: zdoom

Edited November 21, 2021 by HackNeyed

[galileo31dos01]

1 hour ago, HackNeyed said:

DSDA-Doom v0.22 with complevel 21 (MBF21) that vine is impassable.

 

Can confirm. Actually a lot of lines rendered impassable for me, also in m05, pretty strange though my gut tells me it could be something related to old nodes some newest port updates have troubles reading...

[HackNeyed]

Long story short: I suspect it might relate to "MBF21 blockplayers linedef flag" or something I don't know. Maybe @kraflab can shed some light?

 

Long story: Bisecting GZDoom I find that the vine is still passable until version 4.7.0. The release notes mention beta MBF21 support. The Eternity Engine I was running was actually recent git code for what will be version 4.03.00. A quick search of the repo finds "Added MBF21 blockplayers linedef flag" in the notes for version 4.03.00. I uninstalled it and compiled a clean Eternity 4.02.00 and sure enough that hallway was passable again. Of course being a 1996 mod made almost entirely by Macintosh tools I'm not surprised if there are a bunch of superfluous flags interfering with the new standard.

Edited November 21, 2021 by HackNeyed

[GoneAway]

Sounds like the line has an extra flag set that meant nothing at the time but blocks players in mbf21. As far as how or why, I couldn't guess - but that's why complevels exist.

[Azure_Horror]

2 hours ago, kraflab said:

Sounds like the line has an extra flag set that meant nothing at the time but blocks players in mbf21. As far as how or why, I couldn't guess - but that's why complevels exist.

Complevels are a wonderful invention.

Yet, this situation begs a question: suppose I want to play an old mapset with a MBF-21 mod (like Xaser's upcoming Vesper).

Am I correct to assume that this would be impossible, if a mapset has a similar line flag issue?

Edited November 21, 2021 by Azure_Horror

[Rudolph]

Well, good to see it was not just me after all.

 

Hopefully, Cammy will have it fixed in the re-release.

[SMG_Man]

May be worth noting that it was possible for monsters to still pass through the line when I was getting blocked by it in GZDoom. But yeah, I opened up doombuilder and Slade and couldn't find anything jumping out at me about it. Probably have to just redraw the line.

[Andromeda]

Looking at the level in question in the MBF21 mode in UDB, it seems many linedefs have the "Block players" and "Block land monsters" flags. My best guess is the editor used to design the levels back then must have added additional flag data, which was ignored by all executables - that is, until MBF21 appeared and gave a purpose to said superfluous data, which in this case has the unfortunate effect of making the player unable to progress past a certain point.

[Rudolph]

So basically there is just no way to get past the line in GZDoom without cheating?

[SiFi270]

The version included in Compendium doesn't seem to have this problem.