User:Andrew Linden/Office Hours/2008 03 18

Transcript of Andrew Linden's office hours:

[11:02]	Jason Swain:	Hello Rex
[11:03]	Squirrel Wood:	Technical issues, SL architecture, physics engine.
[11:03]	Squirrel Wood:	Thank you :)
[11:03]	Rex Cronon:	hi
[11:03]	Kitto Flora:	Dang that car is still there
[11:03]	Kitto Flora:	Anyone else tried to mute it?
[11:03]	Arawn Spitteler:	What worries me, is that the author has dysAvatrated. Hi, Rex. Have you a copy of the Fast Hobo Train, Andrew?
[11:03]	Andrew Linden:	I deleted it
[11:03]	Squirrel Wood:	^^
[11:03]	Drew Dwi:	xD
[11:03]	Squirrel Wood:	Hello Andrew
[11:03]	Kitto Flora:	Well - maybe it showed up a bug...
[11:03]	Andrew Linden:	Hi everyone.
[11:03]	Jason Swain:	Hello
[11:03]	Rex Cronon:	hi
[11:03]	Kitto Flora:	Does mute object work in H4?
[11:03]	Drew Dwi:	hello
[11:03]	Squirrel Wood:	to the south at the sim edge is another sound spamming vehicle
[11:04]	Andrew Linden:	object mute is a client-side feature
[11:04]	Squirrel Wood:	its an unmanned vehicle sitting on autoreturn off land
[11:04]	Drew Dwi:	Andrew, have you bumped into an issue where you delete an object, but it doesn't actually move, just goes invisible, ie you can't walk through it. It is cleaned up by restarting the sim?
[11:04]	Andrew Linden:	Who's in charge of this region? Aren't you Gaius?
[11:04]	Gaius Goodliffe:	Nope
[11:04]	Andrew Linden:	Oh... Rex?
[11:04]	Gaius Goodliffe:	I think so.
[11:04]	Arawn Spitteler:	I've bumped into such a house.
[11:05]	KFengine2-1 12.1.4 Black whispers: Set to channel 1
[11:05]	KFengine2-1 12.1.4 Black whispers: Reading card, please WAIT....
[11:05]	KFengine2-1 12.1.4 X whispers: Set to channel 1
[11:05]	KFengine2-1 12.1.4 X whispers: Set to channel 1
[11:05]	KFengine2-1 12.1.4 Black whispers: Set to channel 1
[11:05]	Rex Cronon:	yes, what about me?
[11:05]	KFengine2-1 12.1.4 Black whispers: No nearby track!
[11:05]	KFengine2-1 12.1.4 Black whispers: Home set
[11:05]	Andrew Linden:	Or is it Warkirby?
[11:05]	Drew Dwi:	its not a havok4 specific thing, but i've encountered it on havok4
[11:05]	Andrew Linden:	Who's the region owner here?
[11:05]	Gaius Goodliffe:	No, Ryozu is.
[11:05]	Drew Dwi:	Ryozu Kojima
[11:05]	KFengine2-1 12.1.4 Black whispers: Read card
[11:05]	Rex Cronon:	oh, i am not in charge of this place
[11:05]	KFengine2-1 12.1.4 Black whispers: Configured
[11:05]	Arawn Spitteler:	Oh, Kitto. Remember Gumby's Train?
[11:06]	Squirrel Wood:	its group owned
[11:06]	Rex Cronon:	redux dacosta seems to be onwer of land
[11:06]	Andrew Linden:	oh ok. My memory is a blur
[11:06]	Kitto Flora:	Drew Dwi - that sounds like the old general 'gost on delete/take' bug
[11:06]	Kitto Flora:	And I cant mute the steam engine either...
[11:06]	Drew Dwi:	ok, so its known that basicly was my q
[11:06]	KFengine2-1 12.1.4 Black: Sit on the engine to ride
[11:06]	Gaius Goodliffe:	Redux is the estate manager, but Ryozu has admin powers IIRC. (Too many 'R' names -- can't keep it all straight -- sorry Rex.)
[11:06]	Andrew Linden:	Ok, so a Havok4 update...
[11:07]	Rex Cronon:	np
[11:07]	Andrew Linden:	I've been working the last few days on an anti-grief tool for automatically cleaning up some sombombs... after the crash right now, but maybe we'll be able to clean them up before someday
[11:08]	Squirrel Wood:	Humm
[11:08]	Andrew Linden:	Havok4 has opened up a sorta new crash mode
[11:08]	Andrew Linden:	that can kill the entire host, and not just the one simulator process
[11:08]	Squirrel Wood:	Ouch
[11:08]	Rex Cronon:	what does your anti-griefing tool do?
[11:08]	Andrew Linden:	so this stuff is in response to that.
[11:09]	Andrew Linden:	It detects very bad piles of objects on load, and deletes them.
[11:09]	Squirrel Wood:	any chance of detecting them on being rezzed?
[11:09]	Andrew Linden:	Initially it will only be used on load, but we could in theory add it to some real-time checks
[11:09]	Squirrel Wood:	Hello Simon!
[11:09]	Simon Linden:	hi!
[11:09]	Jason Swain:	Hello Simon
[11:09]	Rex Cronon:	hi
[11:10]	Arawn Spitteler:	Add it to the Grey Goo Fence?
[11:10]	Andrew Linden:	The gre goo fence caps certain rez and other script event rates
[11:10]	Squirrel Wood:	you can rez over 200 prims in rapid succession before you even start hitting that fence
[11:11]	Andrew Linden:	we might be able to have the GGF communicate with the bomb squad. I'll think about it.
[11:11]	Squirrel Wood:	Any chance to get that crash mode worked out?
[11:11]	Arawn Spitteler:	They just sound somewhat similar, and might be associated for maintenance, or something.
[11:12]	Rex Cronon:	i was under the impression that h4 could handle large number of physical objects without crashing. how come now is possible to do that?
[11:12]	Andrew Linden:	Squirrel, the most likely way to solve that crash mode would be to actually get some real-time simbomb detection, and also to throttle some operations coming from SL clients.
[11:13]	Andrew Linden:	In the first case, this stuff on load will be a big step toward real-time checks.
[11:13]	Squirrel Wood nods
[11:13]	Andrew Linden:	Rex, Havok4 can handle orders of magnitude more dynamic objects, however not necessarily 3 or 4 orders of magnitude.
[11:13]	Rex Cronon:	what is a simbomb?
[11:14]	Squirrel Wood:	Though griefers will abuse that one quite a bit once they figure it out
[11:14]	Andrew Linden:	I use the term "simbomb" to refer to an object, or collection of objects, designed to crash a simulator.
[11:14]	Squirrel Wood:	as it allows them to take down like four sims at a time
[11:14]	Andrew Linden:	or perhaps also for objects that DO crash a simulator, but on accident.
[11:15]	Jason Swain:	Might I ask, what type of crash mode this particual type of bomb causes?
[11:15]	Jason Swain:	e.g. Is this a faul in Hakov 4 engine or the way it is placed into SL?
[11:15]	Jason Swain:	*fault
[11:16]	Andrew Linden:	There are some flaws in Havok4, but perhaps also the flaws are in how we use it.
[11:16]	Andrew Linden:	The Havok physics engine was made for games, PC and console games.
[11:17]	Andrew Linden:	In games it is easier for the content developers to tune the content to not wander into any possibility zones where the physics engine suffers.
[11:17]	Andrew Linden:	The SL possibility space is much larger than a typical game digital environment, so we still have some zones that can kill Havok4
[11:18]	Andrew Linden:	so, either Havok4 needs to be fixed to fail gracefully under such circumstances
[11:18]	Andrew Linden:	or else we need to add limitations that carve out certain sections of the content possibility space
[11:19]	Andrew Linden:	So... the way we would fix our own use of the physics engine would be to place limitations.
[11:19]	Squirrel Wood:	hmm.. what about a failsafe operation mode with reduced functionality if such a sim bomb "hits" ?
[11:19]	Rex Cronon:	more restrictions:(
[11:19]	Andrew Linden:	However, the actual crash mode is that Havok4 may demand too much memory in too short of time.
[11:19]	Squirrel Wood:	Ah
[11:19]	Jason Swain:	Thanks for answering that one Andrew ^^
[11:20]	Squirrel Wood:	So mayhaps addimg some more ram to the host may fix that ?
[11:20]	Gaius Goodliffe:	Throttle malloc. :)
[11:20]	Squirrel Wood:	or make it harder to happen
[11:20]	Andrew Linden:	So, it isn't a simple segfault where bad logic accidentally left a floating pointer or something.
[11:20]	Andrew Linden:	er... dangling pointer.
[11:20]	Squirrel Wood:	with mono allowing scripts to use more ram it may become neccessary anyway
[11:20]	Simon Linden:	The memory bloat can't be fixed by adding more RAM - it's hundreds of MB, upto and over 1GB
[11:21]	Squirrel Wood:	Ah. I know that a single sim has about 500mb of ram available to it
[11:21]	Rex Cronon:	why don't u use a que for rezzing objects?
[11:21]	Arawn Spitteler doesn't know the current price of Ram
[11:21]	Simon Linden:	I've seen them balloon over 1.5GB and still growing - it gets really slow when it starts swapping VM
[11:21]	Jason Swain:	Can you detect an increase in ram usage and then halt physics for a safe termination and reset?
[11:22]	Squirrel Wood:	hmm.. you sure could detect massive ram usage in time?
[11:22]	Arawn Spitteler:	Detect at first VM swap?
[11:22]	Simon Linden:	I have been adding some code like that - detecting the memory getting too large and trying to handle it gracefully
[11:22]	Andrew Linden:	We do that Jason. If the memory jumpt too high right now in certain circumstances we have to crash out and reset that process.
[11:23]	Andrew Linden:	However, when the region comes back up, the bomb squad should clear out most problems.
[11:23]	Jason Swain:	Ahh I see, very sensible
[11:23]	Andrew Linden:	Once I've got the bomb squad working well, I may add it to the real-time checks. But this is all very new code.
[11:24]	Squirrel Wood:	griefers like to use time bombs so that they don't get cleaned up through a mini rollback on sim restart
[11:24]	Andrew Linden:	Anyway, that is what I've been working on.
[11:24]	Andrew Linden:	Got any H4 development news Simon? I can't remember it all...
[11:24]	Squirrel Wood:	My roller coaster still fails to operate properly on H4 :)
[11:25]	Simon Linden:	Hmmm ... I've been fixing misc. bugs ... got one yesterday which should fix objects getting starved of energy, so pushing and forces will work better
[11:25]	Squirrel Wood:	Nice
[11:25]	Andrew Linden:	"script energy"... one of the bane of my H4 development efforts.
[11:25]	Squirrel Wood:	It is the pure evil!
[11:26]	Andrew Linden:	Squirrel, the nice thing about the bomb squad is that it cleans up the simstate on load, then loads it. Not a rollback.
[11:26]	Squirrel Wood:	Ah
[11:26]	Andrew Linden:	If the bomb squad can detect the problem then it will delete them (and log that event with info).
[11:27]	Squirrel Wood:	Very nice
[11:27]	Andrew Linden:	The tricky part is making sure the bomb squad doesn't flag legit content as the bomb
[11:28]	Squirrel Wood:	hmm
[11:28]	Jason Swain:	Would it delete it perminately or return it to the owner?
[11:28]	Squirrel Wood:	with griefers the alt used is only a couple hours old in 99 out of 100 cases
[11:28]	Andrew Linden:	It currently deletes completely -- gone.
[11:29]	Squirrel Wood:	mayhaps check the flags.. if its no-copy, return, otherwise delete?
[11:29]	Rex Cronon:	the chances are that if 1 day old account rezzes 10k or prims, then the possiblity of it being a griefer, are quite high
[11:29]	Andrew Linden:	I thought about that, but then a griefer could make a no-copy russian-doll type attack that would get ignored.
[11:30]	Jason Swain:	Could it maybe, send the UUID of the object to say the AR team and then if its legit content, the owner can make a ticket for the item, then the AR team just gives the UUID back as an object (I am sure I have over simplified this idea)
[11:30]	Kitto Flora:	How many objects are required to trigger this bomb squad?
[11:31]	Andrew Linden:	The bomb squad isn't quite done
[11:31]	Squirrel Wood:	object age may be a good trigger as most attacks involve some sore of self replicating stuff
[11:31]	Andrew Linden:	but when it is done, we'll probably push it out, with a simple switch for disabling it, should we find that it is too stupid
[11:32]	Squirrel Wood:	so 500+ identical objects owned by the same person may be a good indicator
[11:32]	Andrew Linden:	as it works now, I expect actually less content loss, since it would eliminate a lot of rollbacks for grief attacks
[11:32]	Arawn Spitteler imagines a newbi sim owner laying out 14,000 prims of Kitto Flora Track, as very likely.
[11:32]	Andrew Linden:	yes Squirrel, it already sorts by owner_id frequency, also on some other flags, and tries to do the right thing.
[11:32]	Kitto Flora:	No one does that many
[11:32]	Squirrel Wood:	But all within one minute ?
[11:33]	Kitto Flora:	And there no automated track layer owned by anyone else
[11:33]	Rex Cronon:	squirrel, there are ships, that have way more that 500 prims in them:)
[11:33]	Squirrel Wood:	Yes. But those prims are all different property wise.
[11:33]	Kitto Flora:	How many objects are required to trigger this bomb squad?
[11:33]	Andrew Linden:	no, I don't think Kitto's tracks will awaken the bomb squad
[11:33]	Squirrel Wood:	and usually linked in clumps
[11:34]	Simon Linden:	FWIW the problems also occur when the objects are touching or very close - the trouble occurs when there are ziliions of collisions within a pile of stuff
[11:34]	Andrew Linden:	it requires high prim density to trigger the bomb squad. The tracks would be spread out.
[11:34]	Simon Linden:	... so if it's spread out, there's less trouble
[11:34]	Kitto Flora:	Tracks are also not physical?
[11:35]	Andrew Linden:	the bomb squad also pays attention to the 'dynamic' bit, yes
[11:35]	Squirrel Wood:	So for example 100 nonlinked physical objects that are within, say, a sphere of 2m diameter, would trigger the squad?
[11:35]	Kitto Flora:	How many objects are required to trigger this bomb squad? Is this a state secret?
[11:35]	Andrew Linden:	yes, at the moment it is an obfuscated secret (and also in flux)
[11:36]	Andrew Linden:	those interested will just have to explore the boundaries of the bomb squad logic
[11:36]	Arawn Spitteler:	Is Crash Me open?
[11:36]	Squirrel Wood:	Best keep that number secret so griefers won't know exactly when it triggers
[11:36]	Andrew Linden:	however, you'll probably have to crash a region each time
[11:36]	Gaius Goodliffe:	I suspect it would in part depend on existing memory usage before the bomb went off, too, so there's no number you could pin down.
[11:37]	Andrew Linden:	none of this work is deployed yet, btw. I just got it working this morning.
[11:37]	Simon Linden:	It's not just number - it's shape and position of the objects, how they touch, etc
[11:37]	Gaius Goodliffe nods.
[11:37]	Kitto Flora:	The number is useful for attempting to estimate if a 'legit build' might create that many objects.
[11:37]	Squirrel Wood:	I'm sure you'll get this working well enough to disappoint griefers :)
[11:38]	Kitto Flora:	If they have to be physical objects, I doubt that any legit builder would create more than 100.
[11:38]	Squirrel Wood:	heh. My terraformer rezzes up to 4096 prims. though they are all nonphysical
[11:38]	Arawn Spitteler estimates: If there's any limit to a legit build, it'll be legitimately exceded, probably on a Sunday.
[11:38]	Gaius Goodliffe:	hehe
[11:38]	Andrew Linden:	legit counts of dynamic objects are much greater than 100
[11:38]	Rex Cronon:	kitto, there are guns that can rezz thounsands of bullets in a a few seconds
[11:39]	Andrew Linden:	there are machine guns that shoot >100 bullets a second
[11:39]	Kitto Flora:	Are the bullets physical?
[11:39]	Andrew Linden:	yes
[11:39]	Squirrel Wood:	humm... those should be throttled
[11:39]	Arawn Spitteler:	Wouldn't that hit the Fence?
[11:39]	Squirrel Wood:	they may be using multiple scripts
[11:39]	Rex Cronon:	kitto, most of bullets are temp on rezz
[11:39]	Andrew Linden:	the fence kicks in around 640 rez events per second, or less, depending on the nature of the events
[11:40]	Kitto Flora:	Good way to slow down your hack-n-slash sim
[11:40]	Jason Swain:	I have to admit, playing with physics (safely) on Havok4 with guns, is really good non laggy fun
[11:40]	Rex Cronon:	i should have said they usually are temp on rezz
[11:40]	Squirrel Wood:	A single script can rez 200+ prims as fast as possible before the fence kicks in
[11:40]	Kitto Flora:	50 physical scripted fireflys in a sim make it lag to where the residents complain
[11:41]	Andrew Linden:	not all dynamic objects are created equal
[11:41]	Andrew Linden:	when it comes to lag
[11:41]	Kitto Flora:	Very true
[11:41]	Gaius Goodliffe prefers to create things odd.
[11:41]	Jason Swain:	So different object shapes have different lag causing effects?
[11:41]	Andrew Linden:	anybody have some issues to bring up about Havok4 bugs?
[11:42]	Andrew Linden:	We're planning on declaring it "done" soon.
[11:42]	Gaius Goodliffe:	Those following flight assist behavior (SVC-1195/DEV-9550, SVC-1503, etc.) know it's still not quite right. I did some testing without a flight assist on and think I know what might be causing the continued issues: the huge difference in unassisted flight behavior, which flight-assists attempt to modify and thus rest on top of. You might want to take a look at SVC-1856 if you haven't yet.
[11:42]	Kitto Flora:	There was one Q last week about long term Omega stopping spuriously
[11:42]	Kitto Flora:	Was that resolved?
[11:42]	Arawn Spitteler:	Fast Hobo Train jumped the Tracks in Mocha Beta, but I don't know how different that is.
[11:43]	Squirrel Wood:	If you look up you can see my coaster not working properly ^^
[11:43]	Andrew Linden:	No Kitto. We suspect that to be some lost packet problem, but are not sure.
[11:43]	Gaius Goodliffe:	I think the target omega thing was noted to be a problem in Havok1 as well, and unpredictable.
[11:44]	Squirrel Wood:	try that flight assist. works well on h4
[11:44]	Kitto Flora:	Andrew: There was a request as to where Omega was used long term - I think it may be used in the green rotating hand on the Linden Information Stands. If it is then Orientation Island is a good place to check. But that's still locked up.
[11:44]	Gaius Goodliffe:	@Squirrel: Thanks, but that won't actually fix the problem.
[11:45]	Andrew Linden:	ok kitto, I'll keep that in mind
[11:45]	Kitto Flora:	I have good news for Andrew: If you interested in good news
[11:45]	Andrew Linden:	Gaius, I'll read those SVC items in detail later. Some of them have quite a few comments.
[11:45]	Gaius Goodliffe:	Roger.
[11:46]	Andrew Linden:	squirrel, what is wrong with the roller coaster above?
[11:46]	Squirrel Wood:	not operating smoothly
[11:46]	Squirrel Wood:	it stutters along the track
[11:46]	Andrew Linden:	ok, yeah I see that.
[11:46]	Kitto Flora:	Is it vehicle code?
[11:47]	Squirrel Wood:	nope
[11:47]	Andrew Linden:	ah, it is using hollow tori to follow the track
[11:47]	Squirrel Wood:	pure physical movement. no motors
[11:47]	Kitto Flora:	QED :)
[11:47]	Squirrel Wood:	http://www.youtube.com/watch?v=sdUIqvkzfdQ shows how it works on H1
[11:47]	Andrew Linden:	that isn't going to work well in Havok4 for a while
[11:48]	Andrew Linden:	Squirrel, I suspect you're going to have to modify that roller coaster to use a collection of convex parts instead of tori
[11:48]	Squirrel Wood:	I won't modify it as its not intended for sale :) It is, so far, just an experiment
[11:48]	Andrew Linden:	ok
[11:49]	Gaius Goodliffe:	For the invisible part, would a hollow box work any better, or are all hollow prims going to be problematic?
[11:49]	Andrew Linden:	I have mid- to long-term plans for solving that problem, but it will be a few months
[11:49]	Andrew Linden:	No, don't use a hollow box. Use 4 boxes
[11:50]	Andrew Linden:	also... best to use convex parts for the track when possible
[11:50]	Andrew Linden:	lots of short convex parts are better for the physics engine than one concave curve
[11:50]	Andrew Linden:	however of course you have your prim limits and esthetics to consider
[11:51]	Rex Cronon:	there is a problem with that andrew. and car/airplane if is physical can't have over 30 prims. right?
[11:51]	Gaius Goodliffe:	Ironically, also, SL tries to push you towards fewer prims for building things, I suspect to decress stress on the world, but in this case, it's increasing it...
[11:51]	Squirrel Wood gave you DEV-1422 - Roller Coaster.
[11:51]	Gaius Goodliffe:	*decrease
[11:51]	Squirrel Wood:	Now you have something to experiment with :)
[11:52]	Jcool410 Wildcat:	oh hi warkirby
[11:52]	WarKirby Magojiro:	:D
[11:52]	WarKirby Magojiro:	hai
[11:52]	Andrew Linden:	Yes Rex, the prim limit on vehicles is too simple
[11:52]	Gaius Goodliffe:	Should make concave prims cheaper to build with. :)
[11:52]	WarKirby Magojiro:	am I horribly late, or is everyone early?
[11:53]	Gaius Goodliffe:	Or, move expensive. :p
[11:53]	Andrew Linden:	what I want to do is to make concave objects collide cheaply
[11:53]	WarKirby Magojiro:	or some other answer..
[11:53]	Andrew Linden:	and correctly in all cases
[11:53]	Squirrel Wood:	You are fashionably late
[11:53]	Gaius Goodliffe:	Make *convex* prims cheaper to build with.
[11:53]	Andrew Linden:	er... most cases
[11:53]	Kitto Flora:	Summer time started in USA a week back
[11:53]	Gaius Goodliffe:	err, no.
[11:54]	Gaius Goodliffe looks out his American window at the snow on the ground.
[11:54]	Rex Cronon:	this is funny. we r going to have wheels made out of lenses:)
[11:54]	Squirrel Wood:	hehe
[11:55]	Squirrel Wood:	vista sp1 is officially up for dl
[11:55]	Arawn Spitteler wants a wrap around unicycle.
[11:55]	Kitto Flora:	Tell the clocks that :)
[11:55]	Gaius Goodliffe:	Of course, I'm in Minnesota. Daylight-savings time starts in the winter and ends in the winter. ;)
[11:56]	Andrew Linden:	I'm out of topics. Somone will have to raise one.
[11:56]	Squirrel Wood:	humm...
[11:56]	Arawn Spitteler:	Have we any tracks crossing sim boundaries, in H4, yet?
[11:56]	WarKirby Magojiro:	approx time to release?
[11:56]	Kitto Flora:	GSLR does
[11:56]	Arawn Spitteler:	Tuesday
[11:56]	Squirrel Wood:	time to release: When its done? ^^
[11:56]	Arawn Spitteler:	I've only seen Mocha
[11:56]	Gaius Goodliffe:	Real Soon Now. ;)
[11:57]	Rex Cronon:	whats withe the lag when crossing from one h4 sim to another? i mean the rubberbanding
[11:57]	Andrew Linden:	I'm not supposed to speculate as to when it might be released.
[11:57]	Kitto Flora:	There are monorail tracks crossing H4 sim boundaries - they work
[11:57]	Andrew Linden:	A year ago I thought maybe we were only a month away
[11:57]	Gaius Goodliffe:	hehe
[11:57]	WarKirby Magojiro:	I see. In that case, can you speculate as to what work is left to do ?
[11:58]	Arawn Spitteler:	So the trolley tracks at Ahern, should take the Fast Hobo?
[11:58]	Andrew Linden:	We've got a few bugs we consider outright blockers...
[11:58]	WarKirby Magojiro:	oh dear
[11:58]	Andrew Linden:	I'm not even sure what they all are... I've been focusing on the one I've been working on (bad crash causes region to not come back up).
[11:59]	Andrew Linden:	but I think avatars sliding down hills is one we want to fix
[11:59]	Kitto Flora:	The hills sure are slippery :)
[11:59]	Gaius Goodliffe:	To be expected, this time of year. :)
[11:59]	WarKirby Magojiro:	How are vehicles? Is Cubey Terra happy yet ?
[12:00]	Andrew Linden:	some swimmer attachment doesn't work (vehicle attachments don't work right)
[12:01]	Andrew Linden:	still a broken vehicle or two we'd like to fix, however if we think we can fix them within a few weeks we may declare it done enough to inflict on the world
[12:01]	Arawn Spitteler:	I just ran into that sit target problem again. Is that an H4 problem, or just something needing documentation?
[12:01]	Squirrel Wood:	^^
[12:02]	Simon Linden:	Arawn - we thought that was fixed .... if you can make a simple object with instructions, please file a jira for it
[12:02]	Andrew Linden:	basically, if we can greatly reduce the crash rate for most everybody, then we might let some *fixable* content be broken for a couple of weeks.
[12:02]	Gaius Goodliffe nods.
[12:02]	Squirrel Wood:	People will complain anyway
[12:02]	Andrew Linden:	yes, we expect the complaints to reach a fever pitch
[12:02]	WarKirby Magojiro:	Why are attachment vehicles not working? Attachments aren't physical
[12:03]	Arawn Spitteler:	This morning, I tried setting sit target, by setting a thing at my feet, while sitting, and the sit target wound up someplace else.
[12:03]	Gaius Goodliffe:	It's getting to the point where the problems of Havok4 are worth putting up with if we can get rid of the problems of Havok1.
[12:03]	Gaius Goodliffe:	People are physical.
[12:03]	Andrew Linden:	well, an attachment can call llSetBuoyancy() for example -- applies the behavior to the avatar
[12:03]	WarKirby Magojiro:	ah
[12:03]	Andrew Linden:	so if an attachment were to create a vehicle... should apply to the avatar right?
[12:03]	WarKirby Magojiro:	so is it really avatar physics not working right, or physics calls from attachments?
[12:04]	Andrew Linden:	oddly, somehow I was under the impression that vehicle behavior on attachments don't translate to the avatar
[12:04]	Andrew Linden:	however, someone made some conetent that relies on it
[12:04]	Andrew Linden:	so apparently it works
[12:04]	Arawn Spitteler:	The red balloon?
[12:04]	Gaius Goodliffe:	Whoops. :p
[12:04]	Andrew Linden:	and I coudln't find the code that would have prevented it from working
[12:04]	Arawn Spitteler:	It sets Buoyancy to 1.1
[12:04]	Andrew Linden:	No, not the red balloon
[12:05]	WarKirby Magojiro:	it does seem an odd way to do things. I thought the most logical way for such things was to have a few phys prims as the "actual" vehicle, and the attachment parts purely visual
[12:05]	Gaius Goodliffe:	That's the common way to do it, but apparently not the only way.
[12:05]	Andrew Linden:	in the case of attachments... they don't actually exist in the physics engine, so they slave to the avatar as visual effects
[12:05]	Squirrel Wood:	If there is a way to abuse features, people WILL find it.
[12:06]	Gaius Goodliffe nods.
[12:06]	Andrew Linden:	Yes, we have some creative Residents.
[12:06]	Arawn Spitteler:	We always want to find something to justify our creative unorthodoxy
[12:06]	WarKirby Magojiro:	Well, in lieu of an auto sit function
[12:06]	Andrew Linden:	Ok, I'm going to get back to work
[12:06]	Andrew Linden:	so thank you all for coming.
[12:06]	Squirrel Wood:	Yum! Work!
[12:06]	WarKirby Magojiro:	I suppose such trickery would be necessary, for things like an av transforming to a vehicle
[12:06]	Squirrel Wood:	Have a great day :)
[12:06]	Simon Linden:	Thanks everyone
[12:06]	WarKirby Magojiro:	bye
[12:07]	Squirrel Wood:	And may it be very productive when it comes to fixing bugs :)
[12:07]	Gaius Goodliffe:	Good afternoon!
[12:07]	Kitto Flora:	Goodbye Andrew