Tremulous Forum

General => Announcements => Topic started by: Lakitu7 on January 22, 2011, 01:19:21 pm

Title: Can you do the "light bug"?
Post by: Lakitu7 on January 22, 2011, 01:19:21 pm
It's a funky new dance from the makers of the Jitterbug!!

No, but really I'm talking about a longstanding bug that happens to some people sometimes where players wallwalking on a ceiling may have their camera do a 180 and be right-side-up as if they were on the floor. It's called the "light bug" because it tends to happen when standing on lights in the ceiling of atcs and other maps with similar light fixtures that stick out of the ceiling by super-tiny amounts. I'm not talking about the bug where the camera flips out when two wallwalkers touch. This happens alone.

It happens to some people, but not others. It's never happened to me, and while we've never changed anything at all related that ought to fix it, and the few people who were most vocal about this bug can no longer reproduce it.

If you can repeatedly reproduce this bug using current software (GPP), please post here because I have a pk3 with a potential fix for you to try out. If you have never seen or heard of this and cannot do it, please do not post here because that would not be helpful.

Thanks
Title: Re: Can you do the "light bug"?
Post by: UniqPhoeniX on January 23, 2011, 06:36:34 am
I can only reproduce it in 1.1 :( In karith just outside alien front entrance on the grate ceiling. Any idea which (if any) client settings affect that?
Title: Re: Can you do the "light bug"?
Post by: Odin on January 23, 2011, 07:05:18 am
It has nothing to do with it being a light...

In fact it's because both of the lights are in the shape of pyramids:
ATCS
(http://img709.imageshack.us/img709/4194/lighti.png)

Niveus
(http://img502.imageshack.us/img502/2172/niveus.png)

(Ignore the bad texture coordinates. I converted the map bsps into .map so I could open them in radiant.)
Title: Re: Can you do the "light bug"?
Post by: Lakitu7 on January 23, 2011, 11:04:19 am
PhilH and Odin found ways to reproduce it. Then I figured out that I could reproduce it myself in Linux (but not Windows). I've since found a fix. It has to do with floating point precision crazyness. I'll do more testing tomorrow because it's 3am, but a fix is forthcoming.

Screenshot of the bug:
Title: Re: Can you do the "light bug"?
Post by: mooseberry on January 23, 2011, 09:43:34 pm
It happened to me in 1.2 on Karith (http://www.youtube.com/watch?v=IQpdBWcyYQE).
Title: Re: Can you do the "light bug"?
Post by: jm82792 on January 23, 2011, 09:48:38 pm
PhilH and Odin found ways to reproduce it. Then I figured out that I could reproduce it myself in Linux (but not Windows). I've since found a fix. It has to do with floating point precision crazyness. I'll do more testing tomorrow because it's 3am, but a fix is forthcoming.

Screenshot of the bug:
Out of curiosity where can I find the source code for wall walk?
I know it's off topic(err sorta) but I've been trying to recreate it with only partial success.
Title: Re: Can you do the "light bug"?
Post by: Lakitu7 on January 23, 2011, 10:29:44 pm
okay folks, we got this fixed and it'll go up shortly.

http://svn.icculus.org/tremulous?view=rev&revision=2115

PhilH and Odin found ways to reproduce it. Then I figured out that I could reproduce it myself in Linux (but not Windows). I've since found a fix. It has to do with floating point precision crazyness. I'll do more testing tomorrow because it's 3am, but a fix is forthcoming.

Screenshot of the bug:
Out of curiosity where can I find the source code for wall walk?
I know it's off topic(err sorta) but I've been trying to recreate it with only partial success.

/game/bg_pmove.c
Title: Re: Can you do the "light bug"?
Post by: jm82792 on January 24, 2011, 08:41:22 pm
okay folks, we got this fixed and it'll go up shortly.

http://svn.icculus.org/tremulous?view=rev&revision=2115

PhilH and Odin found ways to reproduce it. Then I figured out that I could reproduce it myself in Linux (but not Windows). I've since found a fix. It has to do with floating point precision crazyness. I'll do more testing tomorrow because it's 3am, but a fix is forthcoming.

Screenshot of the bug:
Out of curiosity where can I find the source code for wall walk?
I know it's off topic(err sorta) but I've been trying to recreate it with only partial success.

/game/bg_pmove.c
Thanks