Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
Nikku4211

Was Final Doom designed for the teleport bug?

Recommended Posts

In the .exe bundled with Final Doom, the teleporters do not set the player's Z co-ordinate like they do in Doom 1 and 2.

 

This is generally considered a bug, stemming from a coder who mistakenly thought the teleportation code changing the player's Z position was unnecessary and removed the line of code. It has been fixed in the Id Anthology collection, but despite that, this bug is commonly supported as a compatibility option in source ports like PrBoom+.

Of course, this is to preserve compatibility with demos recorded using the original Final Doom executable.

 

Still, it makes me wonder if Final Doom was actually designed for this strange teleporter quirk. Was it?

Share this post


Link to post

I doubt they were designed for the teleporter glitch, they were made as Doom II PWADs. Besides, the glitch doesn't have much effect on gameplay, just enough to desync demos but not much else.

Share this post


Link to post
9 minutes ago, Shepardus said:

I doubt they were designed for the teleporter glitch, they were made as Doom II PWADs. Besides, the glitch doesn't have much effect on gameplay, just enough to desync demos but not much else.

Not only that but most teleports in final doom I believe are at the same elevation so the issue isn't even that distracting. 

Share this post


Link to post

I do remember Decino did a video where he showed difference between Doom 2 and Final Doom teleport logic. But I can't find it, because the video wasn't about teleports as main topic.

Share this post


Link to post
18 minutes ago, Shepardus said:

I doubt they were designed for the teleporter glitch, they were made as Doom II PWADs. Besides, the glitch doesn't have much effect on gameplay, just enough to desync demos but not much else.

Milo and Dario Casali created plutonia to be played with doom2 iwad, it was definitely an oversight of some ID developer, this is reaffirmed since in the Id Anthology collection that bug was fixed.

Share this post


Link to post
On 1/11/2022 at 9:13 AM, Dexiaz said:

I do remember Decino did a video where he showed difference between Doom 2 and Final Doom teleport logic. But I can't find it, because the video wasn't about teleports as main topic.

Yup, the Prboom-plus' compatibility options. Here it is ;-)

 

Edit: Adding the code shown on the doomwiki about it

   oldx = thing->x;
   oldy = thing->y;
   oldz = thing->z;
   	
   if (!P_TeleportMove (thing, m->x, m->y))
       return 0;
   
   thing->z = thing->floorz;  //fixme: not needed?
   if (thing->player)
       thing->player->viewz = thing->z+thing->player->viewheight;

 

Edited by Lol 6

Share this post


Link to post
1 hour ago, El juancho said:

Milo and Dario Casali created plutonia to be played with doom2 iwad, it was definitely an oversight of some ID developer, this is reaffirmed since in the Id Anthology collection that bug was fixed.

The Id Anthology executable also fixed other bugs present in the original Doom II executable, so that's not the reason.

Share this post


Link to post
3 minutes ago, GarrettChan said:

I really want a WAD where it can only be played on -cl4 and make the use of teleporter problem.

The first map I ever started, like three years ago used this. It was unintentional, because I had no clue what I was doing lol. But you started in a tech base. The teleporter took you to a canyon, but the canyon had a way lower floor than the tech base. So you spawned at the top of the canyon and fell down. It was cool to me at the time.

Share this post


Link to post
1 hour ago, Andromeda said:

The Id Anthology executable also fixed other bugs present in the original Doom II executable, so that's not the reason.

??? In the ID anthology the bug was fixed so the teleporter bug in final doom .exe was an oversight, I don't understand why are you telling me that a doom 2 bug was fixed in the collection, what does that have to do with the teleporter bug?

Edited by El juancho

Share this post


Link to post
22 minutes ago, Dusty_Rhodes said:

The first map I ever started, like three years ago used this. It was unintentional, because I had no clue what I was doing lol. But you started in a tech base. The teleporter took you to a canyon, but the canyon had a way lower floor than the tech base. So you spawned at the top of the canyon and fell down. It was cool to me at the time.

Well, I mean, it's more like you need to use this teleporter problem to get a high up monsters to trigger a line or shoot a switch. This will break -cl2 or even GZDoom.

Share this post


Link to post

Final Doom's teleporters are different, But they aren't different because they were trying to fix the teleport bug.

Share this post


Link to post
1 hour ago, El juancho said:

??? In the ID anthology the bug was fixed so the teleporter bug in final doom .exe was an oversight, I don't understand why are you telling me that a doom 2 bug was fixed in the collection, what does that have to do with the teleporter bug?

Because if Plutonia/TNT were meant to be played as Doom II PWADs like the Master Levels were, id wouldn't have bothered to make code changes.

Share this post


Link to post
3 minutes ago, Andromeda said:

Because if Plutonia/TNT were meant to be played as Doom II PWADs like the Master Levels were, id wouldn't have bothered to make code changes.

That doesn't make any sense, because they fixed the bug in the id anthology version.

Share this post


Link to post
4 minutes ago, OpenRift said:

That doesn't make any sense, because they fixed the bug in the id anthology version.

Which wouldn't have needed to be fixed if they didn't make code changes for the initial Final Doom release, therefore implying that Plutonia/TNT were meant to be used as IWADs and not PWADs like juancho was saying.

Share this post


Link to post
2 hours ago, Andromeda said:

Because if Plutonia/TNT were meant to be played as Doom II PWADs like the Master Levels were, id wouldn't have bothered to make code changes.

As OpenRift said, that does not make any sense. "id wouldn't have bothered to make code changes", the only "code change" was the teleporter bug which was FIXED in the id anthology (they added level names and intermission screens too), it was fixed because it was an accident, an oversight. Nobody said that the 2 final doom wads were not meant to be iwads, i only said that the Casali brothers designed plutonia to be played along side doom 2 wad...

Edited by El juancho

Share this post


Link to post
2 hours ago, Andromeda said:

Because if Plutonia/TNT were meant to be played as Doom II PWADs like the Master Levels were, id wouldn't have bothered to make code changes.

A short history of Doom v1.9 code changes.

 

In the beginning there was Doom II v1.9. This is the beginning because I'm skipping the previous versions. What you're seeing in complevel 2 is Doom v1.9's normal state. But then there was Ultimate Doom that added a fourth episode to Doom 1. So there were code changes to add the fourth episode, and they also added a fourth demo run. Boom! This complevel 3 is an ultimate Doom v1.9. But then, there was Final Doom. And they felt it'd be really super dumb if the map names and text screens weren't updated. So they took their code base and made more changes! Boom! This complevel 4 is what is known as a Ultimate Doom v1.9 that has ascended above an Ultimate Doom v1.9. Or, you could just call this a Final Doom v1.9.

 

AND THE ANTHOLOGY IS TO GO EVEN FURTHER BEYOND!

 

 

 

Long story short, it's still v1.9 as far as id was concerned. Whoever commented out that bit of code at some point between Ultimate Doom and Final Doom probably didn't think it'd have an impact on demos. They really weren't nearly as bothered with regression-testing demo compatibility as much as the community would be...

Share this post


Link to post
1 hour ago, Gez said:

A short history of Doom v1.9 code changes.

 

In the beginning there was Doom II v1.9. This is the beginning because I'm skipping the previous versions. What you're seeing in complevel 2 is Doom v1.9's normal state. But then there was Ultimate Doom that added a fourth episode to Doom 1. So there were code changes to add the fourth episode, and they also added a fourth demo run. Boom! This complevel 3 is an ultimate Doom v1.9. But then, there was Final Doom. And they felt it'd be really super dumb if the map names and text screens weren't updated. So they took their code base and made more changes! Boom! This complevel 4 is what is known as a Ultimate Doom v1.9 that has ascended above an Ultimate Doom v1.9. Or, you could just call this a Final Doom v1.9.

 

AND THE ANTHOLOGY IS TO GO EVEN FURTHER BEYOND!

 

 

 

Long story short, it's still v1.9 as far as id was concerned. Whoever commented out that bit of code at some point between Ultimate Doom and Final Doom probably didn't think it'd have an impact on demos. They really weren't nearly as bothered with regression-testing demo compatibility as much as the community would be...

I'm aware of everything that you've written by the way. All I'm saying is if id only implemented the bolded changes, there would be no reason for cl4 to exist, as it would effectively be the same as cl3.

Share this post


Link to post
11 minutes ago, Andromeda said:

I'm aware of everything that you've written by the way. All I'm saying is if id only implemented the bolded changes, there would be no reason for cl4 to exist, as it would effectively be the same as cl3.

Of course, and that was most likely the only planned change.

 

It's just that at some point somebody tinkered with the teleportation code, didn't notice the side effect, and forgot about it. Because this was back in the days when "revision control" meant "I copied the entire directory to a set of floppies". There is absolutely no reason to believe that the teleport bug was intended, or even that it was intended specifically for Final Doom.

Share this post


Link to post
1 hour ago, Gez said:

It's just that at some point somebody tinkered with the teleportation code, didn't notice the side effect, and forgot about it. Because this was back in the days when "revision control" meant "I copied the entire directory to a set of floppies". There is absolutely no reason to believe that the teleport bug was intended, or even that it was intended specifically for Final Doom.

I just think it's so funny how a bug that was major enough to affect all teleporters and change the gameplay was kept in most versions of Final Doom like they didn't even playtest the result and now we have to have a compatibility option for it just because that's how most people experienced the game and recorded demos for and agreed that they'll use as a standard for Evilution and Plutonia demos.

 

I'm not even sure if this bug has been exploited much by PWADs for Final Doom.

 

Share this post


Link to post
4 hours ago, Nikku4211 said:

I'm not even sure if this bug has been exploited much by PWADs for Final Doom.

It seems not on top of my head. To a speedrunner, this action is more like an annoyance than something interesting, so I guess probably nobody actually likes it, heh. I said I wanted to make use of this sounds more like sarcastic because I don't use GZDoom, but obviously I am not against GZDoom players :)

Share this post


Link to post
6 hours ago, Nikku4211 said:

I just think it's so funny how a bug that was major enough to affect all teleporters and change the gameplay was kept in most versions of Final Doom like they didn't even playtest the result and now we have to have a compatibility option for it just because that's how most people experienced the game and recorded demos for and agreed that they'll use as a standard for Evilution and Plutonia demos.

 

I'm not even sure if this bug has been exploited much by PWADs for Final Doom.

 

Playtesting wasn't a thing in the 90's.  If they play tested D1 and D2 probably half the bugs would have been fixed ;)

 

Its funny because CVS was around in those days.  It is pretty amazing that nobody noticed it or nobody cared.  But why you'd want to tinker with teleporter code when you didn't have to, in a shipping game!  Is beyond words.

Share this post


Link to post

One example where the teleport bug seems useful is teleporting cacodemons and lost souls into a ceiling alcove, so they have to come down from there to attack you. This would be the only way to make ceiling alcoves more than a decorative detail in vanilla Doom... Still, the effect would be mostly psychological to the player, because gameplay is mostly 2D: monsters have infinite height against player, they'll also go down really fast to your height. Rocket explosions likewise have infinite height, same with the cacodemon "bite" attack range vertically. Walking monsters will instantly drop to floor, without visible falling motion, due to how they're programmed (unlike flying monsters). 

 

For the player I find the Doom gravity too strong to give any lasting impression if you teleport him or her above a pit. 

Edited by printz

Share this post


Link to post
44 minutes ago, printz said:

One example where the teleport bug seems useful is teleporting cacodemons and lost souls into a ceiling alcove, so they have to come down from there to attack you.

According to the wiki, however, "When a monster is teleported, it is spawned on the floor but the teleporter fog remains at the height of origin teleporter." So it isn't even useful for that.

Share this post


Link to post
2 hours ago, Shepardus said:

According to the wiki, however, "When a monster is teleported, it is spawned on the floor but the teleporter fog remains at the height of origin teleporter." So it isn't even useful for that.

See my extra remark above; the grounded monsters do that (I only noticed that with Dehacked when I allowed monsters to travel over cliffs) but not the fliers, unless id added an extra check.

Share this post


Link to post
12 hours ago, Gibbon said:

Playtesting wasn't a thing in the 90's.  If they play tested D1 and D2 probably half the bugs would have been fixed ;)

Playtesting was most definitely a thing in the 90's, I remember coming across a list of playtesters for Wolfenstein 3D v1.0 some years ago for example. Of course, 28 years from Doom's release we know about a lot of its bugs (especially since we have access to the source code), but they're for the most part quite obscure - I doubt that even a big playtesting team would have found half of them.

Share this post


Link to post
31 minutes ago, Andromeda said:

Of course, 28 years from Doom's release we know about a lot of its bugs (especially since we have access to the source code), but they're for the most part quite obscure - I doubt that even a big playtesting team would have found half of them.

I doubt that even a small playtesting team would have missed a bug like Final Doom's teleporters.

 

I guess that means the bug was introduced late in the game's development and thus the levels would not have been designed for it.

 

/shrug

Share this post


Link to post

There's literally a Final Doom text document lying around somewhere out there in the ether, where a member of Team TNT states in no uncertain terms that the teleport thing is a bug, and says something like "but it looks kinda cool".

 

Not exactly sure where to find the .txt file in question or which mapper specifically mentioned it, but yeah. I know most people are aware it was a bug, but it's actually stated definitively by a TNT alum... somewhere..

 

Edit: I knew I wasn't losing my marbles. https://web.archive.org/web/19981206162237/http://www.teamtnt.com/bugfixes.htm

we have some reports of teleport exits making you appear up in mid-air and dropping you. Cool effect, but it's a bug... No fix from us--maybe one day the update from id Software will show up.

Share this post


Link to post
6 minutes ago, Doomkid said:

There's literally a Final Doom text document lying around somewhere out there in the ether, where a member of Team TNT states in no uncertain terms that the teleport thing is a bug, and says something like "but it looks kinda cool".

 

Not exactly sure where to find the .txt file in question or which mapper specifically mentioned it, but yeah. I know most people are aware it was a bug, but it's actually stated definitively by a TNT alum... somewhere..

 

I believe the source for that comment is here.

Share this post


Link to post
7 minutes ago, Nikku4211 said:

I doubt that even a small playtesting team would have missed a bug like Final Doom's teleporters.

To be fair though, it's not as obvious when people were only playing Doom for 3 years or so, and it's not easy to notice side by side as well. It's not like right now the -cl4 bugged teleporter has been written all over the place and so many people are speedrunning/making maps etc., which made this bug way more obvious than before.

 

It's kinda like, you probably will find out something that you didn't know even after these 20+ years of Doom-ing, so I'd say it's fair they didn't find this out back then. Just like, whenever you think the finding of Doom has been exhausted, there're still probably new stuff coming out in the future. Like, who would ever think that Zero Press would be discovered in 2019, right?

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×