[Fixed] Map15 door + decorations physics weirdness

Janizdreg · Post by **Janizdreg** » Sun Feb 15, 2004 6:35 am

Three decorations in Doom2 map15 bounce up & down when I open/close the door located at 1400,-3300. View a demo (recorded using ZDoom 2.0.63) of this here.

Post by **Xaser** » Sun Feb 15, 2004 8:58 am

Yeah. Just recently, Zdoom's Physics have gone completely insane. If there are bad guys that are stuck together, sometimes when you kill one, all the others move upward and just stay floating there. WTF?

Post by **Graf Zahl** » Sun Feb 15, 2004 9:00 am

http://forum.zdoom.org/viewtopic.php?t=1287

But thanks to pointing out a position in a level where it can be tested. It's probably just a minor stupid thing...

Post by **Xaser** » Sun Feb 15, 2004 9:27 am

Graf Zahl wrote:http://forum.zdoom.org/viewtopic.php?t=1287

Oh great... that links to a thread which links to a thread which links to Telebase.wad, one of the most god-awful wads ever made.

Post by **Graf Zahl** » Sun Feb 15, 2004 9:37 am

There are actually 2 bugs at work here:

This code in P_CeilingRaise is responsible for the gib moving up while the door raises:

Code: Select all

	else if (!isgood && thing->z + thing->height < thing->ceilingz )
	{
		if (!P_TestMobjZ (thing) && onmobj->z <= thing->z)
		{
			thing->z = MIN (thing->ceilingz - thing->height,
							onmobj->z + onmobj->height);
		}
	}

The gib on the right side on the inside of the door overlaps with the torch nearby. So while raising the door the code tries to put the gib at the highest possible position below its 'floor' (the top of the torch). The problem is that this code only makes sense for objects which have the MF2_PASSMOBJ flag set. For decorations (especially non-solid ones) it should never be executed.

The second effect (The gib jumping up while the door is moving down) is caused by the following incorrect check in P_PushDown:

Code: Select all

	if (thing->z < thing->floorz)
	{
		return 1;
	}

It should be '<=' instead of '<'.
Anyway, P_PushDown should always check whether the z-position it wants to place an object in is actually lower than its current z-position. It doesn't do that either.

Post by **Xaser** » Sun Feb 15, 2004 9:38 am

Cool, so this crappy physics stuff WILL get fixed. Thanx, Graf!

Post by **Graf Zahl** » Sun Feb 15, 2004 9:39 am

Xaser wrote:
Graf Zahl wrote:http://forum.zdoom.org/viewtopic.php?t=1287
Oh great... that links to a thread which links to a thread which links to Telebase.wad, one of the most god-awful wads ever made.

It's the same bug so the link is valid, don't you think?

Post by **Xaser** » Sun Feb 15, 2004 9:40 am

Graf Zahl wrote:
Xaser wrote:
Graf Zahl wrote:http://forum.zdoom.org/viewtopic.php?t=1287
Oh great... that links to a thread which links to a thread which links to Telebase.wad, one of the most god-awful wads ever made.

It's the same bug so the link is valid, don't you think?

Yes, but did you HAVE to link to telebase.wad? Well, I guess you did, so I'll shut up now.

Post by **Graf Zahl** » Sun Feb 15, 2004 9:46 am

Xaser wrote: Yes, but did you HAVE to link to telebase.wad? Well, I guess you did, so I'll shut up now.

A) What's your problem with Telebase? (I don't know this level.)
B) The bug in Telebase will not be fixed by this. Overlapping monsters in a map is just sloppy mapping and the code I mentioned is designed to unblock them. (But maybe it's a good idea to limit this only to monsters which overlap to such a degree that they cannot move out of each other.)

For decorations it's another matter. They can overlap and overlapping must be allowed at any time.

Post by **Xaser** » Sun Feb 15, 2004 9:52 am

Graf Zahl wrote:
Xaser wrote: Yes, but did you HAVE to link to telebase.wad? Well, I guess you did, so I'll shut up now.

A) What's your problem with Telebase? (I don't know this level.)
B) The bug in Telebase will not be fixed by this. Overlapping monsters in a map is just sloppy mapping and the code I mentioned is designed to unblock them. (But maybe it's a good idea to limit this only to monsters which overlap to such a degree that they cannot move out of each other.)

For decorations it's another matter. They can overlap and overlapping must be allowed at any time.

A) I Made Telebase. It's a very bad level, and it brings back bad memories.

B) Darnit. That baddie stuck together thing is driving me mad! Then again, in that case, I gues it doesn't affect me that much.

Post by **Graf Zahl** » Sun Feb 15, 2004 9:57 am

Xaser wrote: A) I Made Telebase. It's a very bad level, and it brings back bad memories.

Why did you release it then? If I'd be ashamed of a level I'd dump it, not release it.

Post by **Xaser** » Sun Feb 15, 2004 9:59 am

I released it sort of as a "test" to see if I could upload levels okay. Sadly, it worked.

Cutmanmike · Post by **Cutmanmike** » Sun Feb 15, 2004 10:01 am

Fun! I could play with that door all day long

Post by **Graf Zahl** » Sun Feb 15, 2004 10:02 am

Xaser wrote:I released it sort of as a "test" to see if I could upload levels okay. Sadly, it worked.

Now, THAT was stupid...

HotWax · Post by **HotWax** » Sun Feb 15, 2004 1:10 pm

Hey, we were all 13 once...

BTW, be ashamed of this, you supposed "programmer!!"

Graf Zahl wrote:The second effect (The gib jumping up while the door is moving down is caused by the following incorrect check in P_PushDown:

Code: Select all

C_ERR 215: Unexpected end-of-line.  Expected: ')'