Page 1 of 1

"Sealed" on Certain Surfaces

Posted: Sat Feb 03, 2007 8:39 pm
by c2water
On a few surfaces (like the top of the tire tread on the "Two Tanks" map) my status will always changed to "Sealed" and I cannot move. I am also sealed when going through a few teleports (example: the teleports on lasermania) but I think this may be caused by the surface I am teleporting onto.

This is on Ubuntu Edgy. Right now I am using version 2.0.8 from the Ubutnu repository but I have also tried compiling 2.0.8 from source - no difference. I think the problem may have started when I upgraded to Dapper - I have been dealing with this problem for a long time and have just tried to avoid it. Another problem that I am dealing with is a crash on connect if I do not go through "Find Server," but my understanding is this is a bug in libCURL.

Can anyone help me?

Posted: Mon Feb 05, 2007 4:20 pm
by hlfmnhlfamazing
AFAIK this only affects linux/BZflag users.

I'm told that mac and windows users are unaffected.

What's weird about it, at least in my case, is that I can run around on the red side tank/base all I want with no problems. But if I go on the blue side tank/base and I get sealed.

I've only seen it on the "two tanks" level.

Posted: Mon Feb 05, 2007 10:53 pm
by Davy Jones
This is a mapside/clientside (correct me if
im wring) issue, mac and windows users can also get stuck, It has to do with the physics of the game. NOT your OS it can also happen on maps other than "The Two Tanks"

Posted: Tue Feb 06, 2007 9:35 am
by Saturos
I sometimes get sealed on top of teleporters... always wonderes why that happened.

Posted: Tue Feb 06, 2007 1:07 pm
by hlfmnhlfamazing
Davy Jones wrote:This is a mapside/clientside (correct me if
im wring) issue, mac and windows users can also get stuck, It has to do with the physics of the game. NOT your OS it can also happen on maps other than "The Two Tanks"
Well, perhaps I should've been more clear.

The only place I've seen people get stuck consistently(or myself) is on the blue side tank/base of "the two tanks". I've seen others get stuck only on that side as well, whenever I ask them they're always running linux. I've gotten stuck in other places, like on transporters, but it's random.

It may not be the linux OS/kernel per se, but rather one of the dependencies?

The only way I can go on the blue side tank/base is if I've got the wings flag. It still says "sealed" at the top of my screen, the tank moves really slow, and I can't shoot, but it will allow me to jump off.

Hopefully if it is a client side issue it'll be fixed in the next upcoming release.

Posted: Tue Feb 06, 2007 8:47 pm
by CannonBallGuy
Getting sealed is a seemingly random bz event, occuring regardless of OS, etc.
This topic, however, is about getting sealed repeated in the same place and the preliminary research conducted seems to suggest that this occurs only on linux clients.

Posted: Wed Feb 07, 2007 12:38 am
by A Meteorite
hlfmnhlfamazing wrote:It may not be the linux OS/kernel per se, but rather one of the dependencies?
Um... Physics are done inside of BZFlag - it doesn't rely on any other library. BZFlag is actually quite library free (OpenGL, GLEW, and I think it interfaces with platform-specific sound and window drawing libraries) considering some other projects.

There was a map at one time where I would get sealed consistently. I didn't teleport there or anything, just jumped onto a box. I don't remember the map name and I don't believe the server (or map for that matter) is still around today.

This was on a Mac... so it's highly doubtful it's an OS thing...

Posted: Wed Feb 07, 2007 1:49 am
by hlfmnhlfamazing
CannonBallGuy wrote:Getting sealed is a seemingly random bz event, occuring regardless of OS, etc.
This topic, however, is about getting sealed repeated in the same place and the preliminary research conducted seems to suggest that this occurs only on linux clients.
Have you ever tried the two tanks map?

Don't get me wrong, it's a great map. I'm on it constantly. but if I ever get put on the blue side I'll log back out and wait for a red slot to open up.

I find it so odd that it only happens on the blue side tank base. No matter what color you log in as, and no matter the flag.

Posted: Wed Feb 07, 2007 1:51 am
by hlfmnhlfamazing
A Meteorite wrote:This was on a Mac... so it's highly doubtful it's an OS thing...
Meteorite! The universal admin! hehe

I uhhh..... I thought you were a linux user man. What happened?

=^P

Posted: Wed Feb 07, 2007 1:54 am
by bzflaginator
Maybe there is faulty coding in the bzw?

Posted: Wed Feb 07, 2007 5:32 pm
by CannonBallGuy
hlfmnhlfamazing wrote:
CannonBallGuy wrote:Getting sealed is a seemingly random bz event, occuring regardless of OS, etc.
This topic, however, is about getting sealed repeated in the same place and the preliminary research conducted seems to suggest that this occurs only on linux clients.
Have you ever tried the two tanks map?

Don't get me wrong, it's a great map. I'm on it constantly. but if I ever get put on the blue side I'll log back out and wait for a red slot to open up.

I find it so odd that it only happens on the blue side tank base. No matter what color you log in as, and no matter the flag.
Yes, I have played on the map.
And I was actually trying to back you up...

Posted: Fri Feb 09, 2007 7:27 am
by biggeruniverse
The problem, actually, is a common weakness of some physics engines. But here it has several manifestations. The basic case is this: the tank moves along velocity vector, then collisions are checked. If the tank has moved too far along in one time step, it is now inside (or on the other side(the F5 cheat!)) of the object it "collided" with. But where did it come from? This is a posteriori collision detection. When bzflag sees that a tank is even slightly within another collidable object, it considers the tank "sealed", and doesn't go to the trouble of moving it outside the object if necessary. In the case of coming through the teleporter, even an a priori collision detector could not help.

This problem is OS independent, and really the only thing that helps is smaller time steps (higher FPS), and low local jitter (usually caused by IO latency or multi-core time skews).

Bzflag's physics are simple and playable, this is simply a limitation. Map designers should test for it and be careful of it in the meantime before someone enhances or reimplements the physics.

So there is no way but waiting for the map creator?

Posted: Sun Jun 17, 2007 4:53 pm
by nc3
So there is no way to solve the problem but waiting for the map creator to change it?

It's frustrating in the Two Tanks map, because in previous versions I could play with no problem, and then sometime they changed the map and then I couldn't play anymore. It also happens to me in several teleports too (including lasermania), and in the blue base in Battle of Normandie :-(

BTW, I'm also running bzflag 2.0.8 on Ubuntu (Feisty right now).

Is there then any way to contact the creators of these maps or something? It seems that it happens to several people

Posted: Mon Jun 18, 2007 3:44 am
by Macrosoft
well, seems like you just have to wait to see if it gets fixed(probably not)
until then, if you are stuck, you can self destruct ("delete" key) instead of waiting to be killed(not much else you can do)

Posted: Mon Jun 18, 2007 4:54 am
by Saber
How ever I count, I always get to the same answer. 4 months. This topic was dead. :rip:

I've been playing on The Two Tanks recently and I didn't notice anything. I've heard o this was happening (4 months ago) but I didn't see that for a while. Maybe I should just open my eyes and remove my binocles to see what's happening around me.

Posted: Mon Jun 18, 2007 11:32 am
by nc3
Right now there were 6 players, and it was happening to two of us :-)

Yesterday while playing I could see some guy destroying himself on the top of the wheels. So yeah... it still happens. I used to ask if anybody knew why (while playing), but I just stopped and started ignoring it (whenever I'm in that surface, I just press delete).

Posted: Mon Jun 18, 2007 12:31 pm
by Grace F
nc3 wrote:Right now there were 6 players, and it was happening to two of us :-)

Yesterday while playing I could see some guy destroying himself on the top of the wheels. So yeah... it still happens. I used to ask if anybody knew why (while playing), but I just stopped and started ignoring it (whenever I'm in that surface, I just press delete).
I don't play 'The Two Tanks' much so I don't know much about it, but can't you just avoid the dodgy surface? If it's causing you trouble, don't go there...


Since this is a pretty old topic, if nothing has been changed since then, just /report the problem. That probably has already been done, because again, this is an old topic...

Posted: Mon Jun 18, 2007 10:31 pm
by khazhyk
it has been reported several times, but the map maker is too lazy to do anything.

I spawn on the sticky surface half the time when i play on that map.

Posted: Mon Jun 18, 2007 10:43 pm
by Grace F
Oh I see, who is the map maker?


EDIT: Sry made a mistake hehe... :oops:

Posted: Mon Jun 18, 2007 10:44 pm
by TD-Linux
Saber wrote:How ever I count, I always get to the same answer. 4 months. This topic was dead. :rip:
Well, because nc3 wanted to continue on the same topic, this was OK. It provides background information, etc. Resurrecting old topics is not always bad. It shows that nc3 researched his problem before posting, unlike many other people. </rant>

Posted: Tue Jun 19, 2007 2:15 pm
by khazhyk
Oh I see, who is the map maker?
It was mad by a player that goes by the alias of "Stive." He has been contacted several times, but has not responded.

Posted: Tue Jun 19, 2007 3:36 pm
by Tedius
I am not sure Stive is the one you should be trying to contact.

Also it is usually frowned upon to call the person who provided you with your gaming experience "lazy." Perhaps a bit ungrateful?

Posted: Tue Aug 28, 2007 6:11 am
by Bullet Catcher
I experienced the same problems (sealed on Two Tanks treads and in Lasermania teleporter) when running Fedora Core 5 Linux. Now that I have upgraded to Fedora 7 I can move freely about both maps. The BZFlag version is the same (2.0.8) in both cases, but I now have Kernel version 2.6.22 rather than 2.6.20, and my NVIDIA driver is up to 100.14.11 from 87.76. I don't know exactly what makes the difference, but this means there is hope for other Linux users out there.

Posted: Mon Sep 03, 2007 2:55 am
by biggeruniverse
It's not an OS problem. Upgrading major pieces did not help in themselves, but only because they are faster/fix latency issues. Also, 2.1 (2.2) will fix any remaining timing issues on multi-core systems (bzflag 2.1 now limits itself to one core).