altered gameplay behavior in ZDoom

[Graf Zahl]

I decided to restore some of the original gameplay behavior that has been altered in ZDoom over the years. I'll need some help though.

If anyone knows a behavioral change that should optionally be changed back to the original behavior, please post it here.

I already added an option for checking a hit with ranged hitscan weapons but this certainly is not the only issue.

[WOG]

Well, I always wondered why firing a rocket when closely facing a wall barely moved you an inch in ZDoom. The backfire effect is much harder in vanilla Doom.

[Graf Zahl]

I can't confirm that one. It works fine for me. It was a problem in some very old versions though.

[WOG]

That's weird. I'm running the latest svn build + default settings and I still get this behavior. Wonder what could it be.

[Enjay]

Do you have the god mode cheat active?

[WOG]

Yes, that was it. Works correctly without god mode, but guess I was expecting the same behavior I get from vanilla doom in god mode.

[Graf Zahl]

Since this is a cheat it's of significantly less priority than some of the more frequently mentioned things. It's caused by differences in invulnerability handling between Hexen and the other Doom engine games.

[Super Jamie]

I don't know if this is what you're looking for, but I'd like to see an option for ZDoom to change light in adjacent sectors in the manner Boom does, rather than the way Vanilla does.

Also make it play back Vanilla demos :P

[<inactive>Player Lin]

Super Jamie said:

Also make it play back Vanilla demos :P

Seconded this, but I don't expect it really happens.
(I know the demo problem is a mess.)

[Graf Zahl]

Super Jamie said:

I don't know if this is what you're looking for, but I'd like to see an option for ZDoom to change light in adjacent sectors in the manner Boom does, rather than the way Vanilla does.

I think that's one of the missing Boom features. Which lighting special does this?

[Gez]

For the light stuff, see here.

Super Jamie said:

Also make it play back Vanilla demos :P

Waaaaay too much effort involved. And anyway ZDoom sucks as a demo recording platform IMO. It desyncs at the slightest pretext (alt-tab is a surefire way to cause it, as is switching between fullscreen and windowed). You're better off recording your ZDoom demos with FRAPS or something. :p Only thing ZDoom demos are really useful for is debugging certain rare glitch conditions, so that you have an easy way for the devs to reproduce the problem.

(Also, personally, I like it that it doesn't play vanilla demos. Gives some peace and quiet in the title pic. I don't like the automatic playback of demos like vanilla Doom and demo-compatible source ports do, because it is distracting when you're fiddling with the option menu before starting a game. It especially annoys me in EE because some options (for example toggling mouse look) cannot be changed during demo playback. So I'm there, browsing the menu options, then suddenly a demo starts, and I have to get out of the menu, start a new game to shut the demo up, and go back to the menu. It annoys me.)

[Catoptromancy]

Melee weapons!
Chainsaw/staff no longer pulls player in. Can run up and tap a monster and run back while holding fire.

The saw and staff also seem longer. I think its blockmap related. This changes gameplay for me drastically. Heretic has no hitscanners and the extra long staff just makes it even easier to tyson whole episodes. Ive made bug reports and feature requests for flags that restore vanilla blockmap/whatever causes this.

Made a test map that works in Heretic and Doom2. Playing it on multiple ports shows how zdoom can melee monsters that should be unreachable. http://ftpusers.coffeenet.org/~cato/wads/blockmap_test.wad

I am sure some people like the new blockmap, so compatflag would be best for everyone.

There is also hitscanner rape. Many older maps were made and tested with an exe that allows some hitscanner shots to miss. Areas that were designed for a devastating run through hitscanners would be nearly impossible in zdoom.

[esselfortium]

Cato, I'm assuming the "longer staff" is actually the result of ZDoom actually checking the outer boundaries of mobjs for collisions instead of just an X through them. With the original behavior, things get further away from your melee range as you get closer to their center.

I think. Maybe I understand it wrong.

[Graf Zahl]

Indeed. And that's already been taken care of.

And the blockmap thing is next on my list although that's a bit more complicated. I need to find the right idea to handle it.

[Grazza]

Catoptromancy said:

The saw and staff also seem longer. I think its blockmap related.

I think the point of confusion here is that the two changes (separate, albeit thematically linked) were made in the same version, 2.0.51.

+October 29, 2003
[...]
+- Fixed another Doom bug/oversimplification: PIT_AddThingIntercepts() checked
+ the trace against a line running through the middle of the thing. Now it
+ checks against the thing's actual bounding box, so chainsawing big things
+ like the Spider Mastermind is much easier now. This also means
+ P_LineAttack() doesn't need to position puffs/bullet splats closer along the
+ trace since the hit location won't be inside the thing anymore.
+- Changed blockmap thing linking so that things link to every block they touch
+ and not just the block at their center, fixing an old Doom bug.
[...]

Gez: Jamie was joking, you know.

[Graf Zahl]

They are so closely related that they can essentially be considered the same change. In fact to handle both I need to do only one compatibility check. Thanks anyway for posting that changelog because it reminded me that I almost forgot to re-add the puff/splat coordinate fudging.

[Vermil]

There were a couple of differences between ZDoom and the original Heretic that prevented me from making the last map (E3M8) of the Heretic Treasure Chest (HTC) 100% functional on ZDoom:

1. In the original Heretic, tag 666 sectors raise to the next highest floor if there is no lower one.

2. Also, plane movement in all original Doom engine games is blocked if a bad guy is stuck in the ceiling of the sector. In ZDoom it isn't. Of course I know some ZDoom wads that expect this altered behaviour.

The HTC:
http://www.doomworld.com/idgames/?id=16031

3. Also IIRC boss monsters in Heretic don't instantly clip to the floor when walking off a ledge in ZDoom, like they do in the original game.

[Graf Zahl]

Vermil said:

1. In the original Heretic, tag 666 sectors raise to the next highest floor if there is no lower one.

Ouch!

This has been wrong forever in ZDoom and nobody ever noticed...
In Doom a 666 floor lowers to the lowest neighboring floor, in Heretic to the highest neighboring floor. This is an actual bug, not some deliberate change...

[phi108]

ZDoom Changelog said:

-restored original Doom behavior for hitscans to only check actors which have their center in the blockmap cells being checked, compatibility optioned by COMPATF_HITSCAN
...
-Added a Boom (strict) compatibility mode.
-Restored some original Doom behavior that received complaints from users:
-reactivated the old sliding against diagonal walls code and compatibility optioned it with COMPATF_WALLRUN.
-re-added the original hitscan checking code using a cross-section of the actor instead of the bounding box, compatibility optioned with COMPATF_HITSCAN.

Wow, great work Graf! I admit these changes didn't really ever bother me, but I wasn't playing vanilla doom for 8 years straight before using ZDoom. I still love the ability to set as many compatibility options as possible, and I'm sure oldschool doomers will be very happy to see these options.

[Dragonsbrethren]

Yeah, thanks Graf, this is really awesome.

[Super Jamie]

Graf Zahl said:

I think that's one of the missing Boom features. Which lighting special does this?

We spoke about it here before - http://forum.zdoom.org/viewtopic.php?f=3&t=22700

I log bugs whenever I notice a missing or different Boom feature. It's pretty much all I use my ZD Forums account for ;)

[Cole Burna]

That's great news. You can never have too much vanilla Doom in a source port.

What if you temporarily enabled vanilla demo playback in ZDoom? that would allow us to spot some of the least obvious differences more clearly.

Also, can the way ZDoom renders architecture change an actor's behavior in any way? by comparing a vanilla screenshot and a ZDoom screenshot at 320x200, it becomes evident that ZDoom does stuff differently, but I never knew if that had any extra undesirable implications.

Thanks.

[andrewj]

Vermil said:

2. Also, plane movement in all original Doom engine games is blocked if a bad guy is stuck in the ceiling of the sector.

I don't think that is correct, in MAP06 of DOOM2 there is a chaingunner overlapping an opening door (near the spiral staircase) and that door opens fine in Vanilla.

[Never_Again]

[Graf Zahl]

That one's a well known bug. I also know a few old maps suffering from it - but this was fixed in Boom, not ZDoom.

Are there really maps depending on this glitch? In all circumstances where I witnessed it it has bad side effects that broke the map in one way or another.

[ReFracture]

Ah, I was gonna mention how you can't shoot through decorations with projectiles, but I see that has been taken care of already.

What about the pain face on the status bar that is made when you hold the fire button?

In vanilla or boom, if you click to shoot the ssg, and then press and hold click again just before the reload animation ends, you will get the pain face, you have to hold it the entire time in ZDoom or you will never get it. This is a minor issue that doesn't really relate to game play though.

This behavior has been here for a long time, always bothered me slightly but never really enough to complain.

[Graf Zahl]

I won't change anything that' actually a bug fix with no impact on gameplay.

The idea here is to address the big gameplay issues that keep certain people from using ZDoom.

[Graf Zahl]

Super Jamie said:

We spoke about it here before - http://forum.zdoom.org/viewtopic.php?f=3&t=22700

I log bugs whenever I notice a missing or different Boom feature. It's pretty much all I use my ZD Forums account for ;)

The 'bugs' forum is a better place for something that needs to be addressed and shouldn't get lost. Anyway, this will be the next one I'll try to address.

[ReFracture]

Graf Zahl said:

I won't change anything that' actually a bug fix with no impact on gameplay.

The idea here is to address the big gameplay issues that keep certain people from using ZDoom.

You're quite right, I don't really have anything else to add in that case.

[printz]

andrewj said:

I don't think that is correct, in MAP06 of DOOM2 there is a chaingunner overlapping an opening door (near the spiral staircase) and that door opens fine in Vanilla.

In vDoom, doors are exempt from the restriction, and always open even if someone is blocking them. But moving floors, and probably lifts too, won't move. Placing monsters to block floors in vanilla Doom isn't very recommended, because they will block both the sector they're within, and any nearby ones.

EDIT: can the sound limit be disabled in ZDoom? It's not a gameplay feature per se, but I like hearing all the possible sound.