User:Andrew Linden/Office Hours/2007 10 02

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Transcript of Andrew Linden's office hours:

[20:57] Sidewinder Linden: andrew should be here soon
[20:57] Nyk Sinister: ok
[20:58] Tiberious Neruda: Ryozu can tell you about the Shadow....
[20:58] Kitto Flora: But griefers will be happy to lock a sim at < 0.5. BUT it looks like they have to be able to rez a lot to do that - and that should be preventable
[20:58] Ryozu Yamamoto: Oh yeah, great fun there, ever played Asteroids?
[20:58] Nyk Sinister: ah, andrew welcome
[20:58] Tiberious Neruda: but I noticed the Sentra (Nissan's official car) wouldn't turn at all, no matter how much I tried
[20:58] Sidewinder Linden: many sims won't have enough prims available to do taht ;)
[20:58] Sidewinder Linden: hi andrew
[20:58] Andrew Linden: I made it
[20:58] Vincent Nacon: ....Andrew, no offence but I can't believe youre wearing that for th meeting
[20:58] Vincent Nacon: muhahahaha!
[20:58] Ryozu Yamamoto chuckles
[20:58] Nyk Sinister: well... i have a tux to wear
[20:58] Kitto Flora: https://jira.secondlife.com/browse/SVC-756 <- Major problem affects all cars and sleds on roads and other prims.
[20:58] Andrew Linden: Vincent, I've been wearing this for almost two years.
[20:59] Nyk Sinister: but the grim reaper loves meetings
[20:59] Tiberious Neruda: wasn't on road....
[20:59] Andrew Linden: In many ways, I'm a total noob.
[20:59] Tiberious Neruda: was on plain ground
[20:59] Vincent Nacon: oh now now, you're linden, not a noob
[20:59] Kitto Flora: Humm, my test vehicles on plain ground worked ok.
[20:59] Sidewinder Linden: do we have a couple more chairs in case?
[20:59] Nyk Sinister: indeed, you are very skilled
[21:00] Sidewinder Linden: these are nice btw
[21:00] Tiberious Neruda: but my cheapie little Mario Kart worked quite nicely
[21:00] Vincent Nacon: ty
[21:00] Andrew Linden: Kitto, your vehicles worked ok on the Havok4 preview?
[21:00] Kitto Flora: No
[21:00] Kitto Flora: In spades, no
[21:00] Vincent Nacon: I'm gonna start logging for Francis, since she can't be here today
[21:00] Nyk Sinister: i dont understand much of this speak... so forgive me
[21:00] Kitto Flora: On bare ground - yes
[21:00] Andrew Linden: Ok good. I'm not going insane then.
[21:00] Ryozu Yamamoto: For you Jira-ites.. https://jira.secondlife.com/browse/SVC-754 <- Am I doin it right?
[21:00] Kitto Flora: Over prims - dead in 3 meters
[21:01] Nyk Sinister: that boat was a nice touch
[21:01] Andrew Linden: well, the office hours are now in session
[21:01] Tiberious Neruda: oh... another question: are there plans to tweak how much friction is applied to physical spheres?
[21:01] Nyk Sinister: and me being an unoffical office worker... lmao
[21:01] Sidewinder Linden: ok guys... so like the last session
[21:01] Andrew Linden: I don't really have anything on the agenda
[21:01] Andrew Linden: except Havok4
[21:01] Sidewinder Linden: let's try to do one question, one answer ok?
[21:02] Sidewinder Linden: rather than five overlapping questions ;)
[21:02] Tiberious Neruda: heheh
[21:02] Nyk Sinister: lmao
[21:02] Ryozu Yamamoto: So, a q&a session
[21:02] Sidewinder Linden: sure
[21:02] Nyk Sinister: indeed
[21:02] Nyk Sinister: that would work
[21:02] Sidewinder Linden: well maybe before we go to questions...
[21:02] Andrew Linden: let's start it out with Q&A
[21:02] Ryozu Yamamoto: I have a question: Do you have any important questions for us? XD
[21:02] Sidewinder Linden: andrew do you want to talk just a minute about what we've already got figured out from the first few days?
[21:02] Andrew Linden: You have something to say Sidewinder?
[21:02] Nyk Sinister: i feel important... *smiles*
[21:02] Sidewinder Linden: crash modes etc
[21:02] Andrew Linden: We'll consider that the first question.
[21:03] Kitto Flora: YEah , how bout summarize whats bugs been found that you are going to fix
[21:03] Andrew Linden: The only thing of interest in the last few days is this:
[21:03] Andrew Linden: There are maybe three (probably only two) distinct crash modes that I was finding in Havok4 preview.
[21:04] Andrew Linden: I examined the core dumps and logs
[21:04] Andrew Linden: One of them is fixed.
[21:04] Nyk Sinister: havok4 is a program?
[21:04] Ryozu Yamamoto: Nyk: Well, yes. It's a binary plugin so to speak
[21:04] Andrew Linden: The other one... I need a repro recipe. I don't know how to trigger it.
[21:04] Ryozu Yamamoto: Or can be used that way from what I understand
[21:04] Vincent Nacon: an physic engine core
[21:04] Andrew Linden: I'm going to try to update the Havok4 preview tomorrow
[21:05] Andrew Linden: and hopefully somone could find the repro for the mystery crash.
[21:05] Andrew Linden: Havok4 is a series of libraries, with an SDK
[21:05] Ryozu Yamamoto: Any idea who was in the sim when it happened?
[21:05] Sidewinder Linden: title green sidewinder
[21:05] Nyk Sinister: ahh ok
[21:05] Vincent Nacon: like a pre-log?
[21:05] Andrew Linden: basically, it is a chunk of C++ code that we didn't have to write, but we can use as if we did.
[21:05] Vincent Nacon: 2nd question would be, how are you gonna deal with vehicle issue or even maybe think about replacing it with havok 4's vehicle core system?
[21:06] Sidewinder Linden: it calculates the information needed to make collisions, inertia and such in the world
[21:06] Andrew Linden: The problem I was aware of for ground vehicles in Havok4 is fixed... I think.
[21:06] Andrew Linden: I fixed it late Friday night, or early Saturday morning.
[21:06] Kitto Flora: What was that?
[21:06] Nyk Sinister: i had a question of the objects including space ships and etc, some dont work on this land and i am unable to fly it
[21:06] Kitto Flora: (which)
[21:07] Sidewinder Linden: so that will be in the refresh this week?
[21:07] Vincent Nacon: oh rat.... was hoping that it was kinda doomed that you may have to redo the whole thing with Havok 4's vehicle system ;)
[21:07] Sidewinder Linden: hehe @vincent
[21:07] Tiberious Neruda: ok... I'd like to ask a question, whenever you're ready for it
[21:07] Andrew Linden: Nyk, you're saying you have some broken content in the Havok4 preview?
[21:08] Ryozu Yamamoto: Broken content? Oh lawdy do I have some broken content
[21:08] Nyk Sinister: if i accidently interupt with a question too fast i can wait
[21:08] Nyk Sinister: i think that is the case
[21:08] Andrew Linden: yes sidewinder, the vehicle fix has been checked in, so it would be in any update on Wednesday
[21:08] Nyk Sinister: i can manifest the ship later
[21:08] Tiberious Neruda: I think it's safe to say we ALL have some broken content as it stands now
[21:08] Ryozu Yamamoto nods at Tiberious.
[21:08] Nyk Sinister: but i can start it up, its just that it wont fly
[21:08] Kitto Flora: Andrew, what problem did the vehicle fix fix?
[21:08] Andrew Linden: If anyone has broken content in Havok4 preview they can give me a copy with an IM describing the problem.
[21:09] Andrew Linden: I may be able to test it and see what is breaking it.
[21:09] Tiberious Neruda: I don't think I can... it's no-transfer
[21:09] Tiberious Neruda: but I know you can take a copy if I'd rezzed it
[21:09] Nyk Sinister: ok, it could be that or maybe the commands... but im sure i tried everthing
[21:09] Vincent Nacon: I could give you my car script..... but it's too good to pass out yet
[21:10] Tiberious Neruda: oh!
[21:10] Andrew Linden: O
[21:10] Tiberious Neruda: but that'll have to wait 'til after the meeting....
[21:10] Nyk Sinister: np
[21:10] Nyk Sinister: i can wait
[21:10] Vincent Nacon: but I'm sure they have been taken care of for the fixes you said
[21:10] Andrew Linden: at the moment, I'm not going to worry about reports of ground vehicles being broken, until after Wed
[21:10] Tiberious Neruda: (as it doesn't have anything to do with Havok4)
[21:10] Vincent Nacon: sound good
[21:10] Kitto Flora: OK
[21:10] Nyk Sinister: its an air vehicle
[21:11] Andrew Linden: The problem was that the ground collisions are a little different in Havok4, and vehicles tend to snag and tumble
[21:11] Vincent Nacon: aye
[21:11] Nyk Sinister: that reminds me...
[21:11] Andrew Linden: I added some "magic" to the vehicle code to help smooth ground vehicle collisions
[21:11] Ryozu Kojima: Avatars too
[21:11] Kitto Flora: Do you really mean collisions with the *ground* (not prims)?
[21:11] Vincent Nacon: ehh.... what you mean by that?
[21:11] Tiberious Neruda laughs. "Just change the wheels to be spheres for collision purposes"
[21:11] Ryozu Kojima: Avatars being pushed by physics scripting do almost nothing now
[21:11] Andrew Linden: Yes, collisions with the ground
[21:11] Nyk Sinister: andrew, the ground motorcycles and cars are jolting too fast asorting with inertia
[21:11] Andrew Linden: Tiberious, you had a question?
[21:11] Tiberious Neruda: yes
[21:12] Andrew Linden: ask
[21:12] Kitto Flora: OK. 3 of the vechicles I tested all worked nominally on the ground, except for the 5 degree tilt
[21:12] Tiberious Neruda: as it is now on the beta grid, spheres roll almost indefinately. Are there any plans to tweak the friction on them to more realistic levels?
[21:12] Nyk Sinister: if they have phantom, it wont matter
[21:13] Tiberious Neruda: that's question #1 from me, at least
[21:13] Andrew Linden: yes, I need to tweak the implicit spheres some more -- to stop them from rolling forever.
[21:13] Andrew Linden: That is a known issue.
[21:13] Tiberious Neruda: ok
[21:14] Tiberious Neruda: that's good to know
[21:14] Nyk Sinister: what does Temporary do for an object
[21:14] Andrew Linden: The avatars not being pushed by scripts... I'm not suprised by that problem
[21:14] Ryozu Yamamoto: I doubt it does anything as far as physics is concerned
[21:14] Tiberious Neruda: Nyk: makes it automatically die after ~60 seconds
[21:14] Ryozu Yamamoto: Temp that is
[21:15] Andrew Linden: the avatar control code had to suffer a major rewrite because a feature in Havok1 vanished in Havok4
[21:15] Nyk Sinister: ill take that into consideration when i am making traps
[21:15] Tiberious Neruda: I noticed that
[21:15] Ryozu Yamamoto: Andrew: It's a couple of problem theres. 1) Avatars at rest, stay at rest. 2) The ground causes massive friction/damping of lateral movement
[21:15] Andrew Linden: I'm not sure I can recover that behavior. What kind of content needs to push the avatar around?
[21:15] Ryozu Yamamoto: Well, actually, everything does, I think
[21:15] Sidewinder Linden: weapons...?
[21:15] Ryozu Yamamoto: Well for one, there's a lot of products
[21:15] Tiberious Neruda: well, I have a double-jump script that uses an llPushObject on the wearer
[21:16] Tiberious Neruda: (and seems to have gone missing from the database, BTW)
[21:16] Ryozu Yamamoto: To name a few: Teleport to Camera such as Mystitool, OmniPhaze, jFlash, and short range teleports, such as OmniPhaze, jFlash, Impulse Booster
[21:16] Kitto Flora: Common use of push av is on standing up, to get av clear of what they sat on
[21:16] Kitto Flora: Also used in some games
[21:16] Andrew Linden: Yes, OmniPhaze I'm familiar with.
[21:16] Kitto Flora: Also yused in jet attachments
[21:16] Ryozu Yamamoto: ;)
[21:16] Tiberious Neruda: OH!
[21:16] Ryozu Yamamoto: In Havok1, a standing avatar phazing forward goes.. well, forward
[21:16] Ryozu Yamamoto: On Havok4, they kindof, either don't move, or bounce backwards O_o
[21:17] Andrew Linden: Well, I'll see what I can do. Someone give me some copies of "push avatar" content in the preview and I'll test them out.
[21:17] Nyk Sinister: oh, i just rememberd a valid item i need, i would like to know where to obtain an invisablity script or animation.
[21:17] Tiberious Neruda: MAJOR issue I noticed: when wearing the Flight Feather, at ~500m up, flying down is nearly impossible
[21:17] Nyk Sinister: oh, that would be something to check
[21:17] Ryozu Yamamoto: It basically seems that, being Not "In Air" causes the avatar's max movement to be capped at running/walking speed?
[21:17] Nyk Sinister: hover items seems to be working very well
[21:17] Kitto Flora: I also suspect there's race cheat attachments that use push on the attached avatar
[21:18] Andrew Linden: That could be Ryozu.
[21:18] Ryozu Yamamoto: There's one script I know of, Impulse Booster, another movement enhancer, that uses llSetForce to move an avatar. In the air, it works perfect, but when on the ground, at best, an av just walks
[21:18] Kitto Flora: (If they became impossible, I'd be happy.)
[21:18] Sidewinder Linden: i seem to recall a weapon that did a blowback/recoil on the avatar.. trying to remember whose...
[21:18] Ryozu Yamamoto: I'll toss you my copy on Beta
[21:19] Tiberious Neruda: are we going to Beta after this, by the way?
[21:19] Andrew Linden: I'll have to play around with some content. I phear the avatar control code.
[21:19] Kitto Flora: WAsnt the recoil built in the rezzing a projectile with velocity?
[21:19] Ryozu Yamamoto: Also, have you two seen my videos on llMoveToTarget?
[21:19] Ryozu Yamamoto: http://youtube.com/profile_videos?user=n1nj4Ryozu
[21:19] Andrew Linden: No, I haven't seen the videos.
[21:19] Ryozu Yamamoto: There's a pretty steep contrast in behavior with the exact same code
[21:19] Tiberious Neruda: I might need to check that out
[21:20] Andrew Linden: Tiberious, what do you mean "Beta after this"?
[21:20] Tiberious Neruda: (I have an item that relies on MoveToTarget)
[21:20] Tiberious Neruda: well, after this meeting, are we all gonna re-convene on the beta grid?
[21:20] Andrew Linden: Alas, I cannot.
[21:20] Ryozu Yamamoto: The other issue I'm concerned about is that scripted physics on an avatar doesn't seem to awaken it's ?
[21:20] Ryozu Yamamoto: I am Tib =D
[21:21] Nyk Sinister: before it is finish, may i ask for directions to get an invisability code of some sorts?
[21:21] Andrew Linden: Ryozu, scripted from an attachment? or from an outside object?
[21:21] Ryozu Yamamoto: I've only really tested llMoveToTarget in an attachment so far
[21:21] Ryozu Yamamoto: I start llMoveToTarget while my avatar is stable, and it does nothing. If I move, it suddenly goes into effect
[21:21] Andrew Linden: ok, so I'm hearing about problems with pushing avatars, and vehicles in general
[21:22] Andrew Linden: any other categories?
[21:22] Ryozu Yamamoto: Avatar rotation
[21:22] Sidewinder Linden: i haven't seen the jira yet, but someone demonstrated a problem with building
[21:22] Andrew Linden: I've got a QA engineer who was going to go through the pjira bugs and send me a summary
[21:22] Sidewinder Linden: that changing the root prim reoriented other prims already linked
[21:22] Ryozu Yamamoto: Ah, yes, linking, Sidewinder? That video is on my Youtube as well
[21:22] Sidewinder Linden: err linking to a new root prim i think
[21:22] Kitto Flora: I heard about Av Attachments getting moved around on sim boundary crossing.
[21:22] Ryozu Yamamoto: Yeah
[21:22] Sidewinder Linden: yes saw that
[21:22] Ryozu Yamamoto: Linking is generally borked
[21:22] Tiberious Neruda: yeah....
[21:23] Ryozu Yamamoto: And attachments are a form of linking, so I understand
[21:23] Tiberious Neruda: that's why my tail kept going to the side like I was in heat....
[21:23] Sidewinder Linden: if you have an attachment "away" from the default attach point, it gets moved to the default attach point when crossing regions
[21:23] Ryozu Yamamoto: Also when re-attching
[21:23] Tiberious Neruda: wondered why that happened
[21:24] Andrew Linden: well, I'll be fixing bugs all week, and next week too
[21:24] Vincent Nacon: there's some questions that Francis wanted to ask.... - broadphase/narrowphase collision detection? - floating point precision? - universal speed limit?
[21:24] Ryozu Yamamoto: Sorry Andrew ^_^
[21:24] Ryozu Yamamoto: Oh! Speaking of universal speed limit!
[21:24] Kitto Flora: The av attachment shift problem has been around before, and .. is it Havok4 connected???
[21:24] Tiberious Neruda: and i'd like to ask my second question in a bit as well
[21:24] Andrew Linden: ask Tiberious
[21:24] Tiberious Neruda: ok...
[21:25] Ryozu Yamamoto: This one I'm not sure about, if it's different in Havok1, but I'm pretty sure it is. Giving llSetForce a value too high a force setting causes it to fail
[21:25] Nyk Sinister: sorry that ive spoken out of tern, im not use to meetings such as these, and im jumpy
[21:25] Andrew Linden: Vincent, do you recall the exact questions? That list didn't quite express the questions very well.
[21:25] Raynor Zenovka: ooo is this a party?
[21:25] Ryozu Kojima: Linden Office hours Raynor =)
[21:25] Ryozu Kojima: Discussing the new physics engine on the beta grid
[21:25] Vincent Nacon: no, it was posted on a forum, just copied & pasted
[21:26] Raynor Zenovka: cool
[21:26] Tiberious Neruda: after rezzing two of the 150m 'mega-spheres' on Bug Island, and having Havok4 not even strain to take them apart when I made 'em physical, is there any possibility of raising the max size of prims?
[21:26] Raynor Zenovka: oh like real physics?
[21:26] Nyk Sinister: if i may ask my 5th question to you andrew in a bit
[21:26] Raynor Zenovka: i love physics i mod HL2 physics engine
[21:26] Andrew Linden: ok, so llSetForce() just fails when the input is too large?
[21:26] Ryozu Yamamoto: Seems that way, I haven't narrowed it down however
[21:27] Vincent Nacon: ahh want a seat, Ray?
[21:27] Andrew Linden: it should probably just cap to something
[21:27] Ryozu Yamamoto: It may be only diagonal settings
[21:27] Andrew Linden: The max prim size will not increase yet
[21:27] Ryozu Yamamoto: But when too high, the avatar just.. stops moving
[21:27] Raynor Zenovka: well i dont want to be somewhere im not invited to lol
[21:27] Raynor Zenovka: i guess i just showed up at the wrong place
[21:27] Ryozu Yamamoto: It's demonstrated quite well with the Impulse Booster
[21:27] Raynor Zenovka: stupid home setting..
[21:27] Vincent Nacon: np it's free for all
[21:27] Ryozu Yamamoto chuckles
[21:27] Andrew Linden: before prim sizes increase we need to fix the problem with prims overlapping on other people' sparcels
[21:28] Vincent Nacon: eh?
[21:28] Ryozu Yamamoto: Ah, yeah, that's a cool idea, though I fear it will break things like driveways going onto Linden roads
[21:28] Andrew Linden: I'm hoping that I can use Havok4's asynchronous collision detection to solve that parcel overlapping problem
[21:28] Vincent Nacon: ah
[21:28] Tiberious Neruda: right. The previously-stated reason for keeping the limit at 10m was stated to be collision issues
[21:28] Ryozu Yamamoto: Talking about using the bounding box instead of prim center to judge overlap
[21:28] Andrew Linden: that is, provide the parcels with a collidable body, and query the phys engine to see if an object is penetrating
[21:29] Ryozu Yamamoto: Or that ;)
[21:29] Kitto Flora: Neat idea Andrew!
[21:29] Vincent Nacon: alrighty, now about feature suggestions... ready for `em?
[21:29] Andrew Linden: sure go ahead
[21:29] Tiberious Neruda: if Havok4 fixes these, then it should be simple to raise the max size to... say 40m or so?
[21:29] Sidewinder Linden: vincent - you know the caveat about features, right? ;)
[21:29] Ryozu Yamamoto: May as well put them on the board, though I won't expect anything for a long time
[21:30] Vincent Nacon: first thing would be a wheel/motor param for child prim in a linset car/boat/planes
[21:30] Andrew Linden: Tiberious, if we were to solve the prim overlapping problem, then I'd let you have as big of prims as you could fit on the parcel
[21:30] Ryozu Yamamoto chuckles
[21:30] Vincent Nacon: yeah caveats aren't enough for me ;)
[21:30] Ryozu Yamamoto: That'd be awesome
[21:30] Andrew Linden: wheels... those fall under the category of "jointed objects"
[21:31] Ryozu Yamamoto: Simple machine prims
[21:31] Andrew Linden: jointed objects is a Biggish project
[21:31] Ryozu Yamamoto: I'd be ecstatic
[21:31] Andrew Linden: that would require a major overhaul of some simulator code
[21:31] Kitto Flora: Whats this wheel etc param going to do?
[21:31] Nyk Sinister: i shall be leaving
[21:31] Nyk Sinister: ty for letting me join in
[21:31] Ryozu Yamamoto: Ah, take care Nyk
[21:31] Andrew Linden: so we aren't going to tackle joints immediatly after Havok4
[21:31] Andrew Linden: Nice talking with you Nyk
[21:31] Sidewinder Linden: thanks for coming nyk
[21:31] Vincent Nacon: ahh well, what I really meant like motor drive or a "force" sources but I'm guessing using joints as spring/shock system for a car?
[21:31] Nyk Sinister: ill be back for the next random meeting
[21:32] Sidewinder Linden: andrew - since this keeps coming up, would you like to say anything about havok5 vs additional fixes and features on havok4?
[21:32] Vincent Nacon: aye I'd like to have a tank's tread drives or a AWD car
[21:32] Ryozu Yamamoto: Having the material prim property define some physics settings like compressability/springyness would be pretty cool
[21:32] Andrew Linden: Wheels on a car is slightly different from jointed objects in general
[21:32] Tiberious Neruda: oh... someone mentioned the upgrade to Havok4 having the side effect of allowing linksets > 31 prims to be physical
[21:33] Andrew Linden: we had a proposal that was kicking about the lab about how to do wheels on cars
[21:33] Andrew Linden: but it was also a biggish project
[21:33] Ryozu Yamamoto: Tib: I think that's a 'bug'
[21:33] Vincent Nacon: yes that was me
[21:33] Kitto Flora: Um - linear motor is a pretty good drive system, so is the rotational one.
[21:33] Vincent Nacon: my 2nd suggestion
[21:33] Vincent Nacon: :P
[21:33] Andrew Linden: I'd rather do joints first -- it would probably make wheels on cars easier to do
[21:33] Vincent Nacon: alrighty
[21:33] Vincent Nacon: and about the 31 prims for physic
[21:33] Tiberious Neruda: well, if it works and doesn't cause any problems, why not make that the first real 'feature' to come with havok4?
[21:33] Kitto Flora: Uh - one simply rotates the textures on the wheels
[21:33] Ryozu Yamamoto: Agreed
[21:34] Vincent Nacon: can't you allow a simple code to control the bounding boxes?
[21:34] Andrew Linden: the main problem with 31 prims for dynamic objects is the border crossing problem
[21:34] Andrew Linden: it is independent of Havok4
[21:34] Ryozu Yamamoto hums, "The textures on the wheels go round and round...."
[21:34] Vincent Nacon: so we can have 256 prims but only 31 prims are physical
[21:34] Vincent Nacon: where other prims act as phantom
[21:34] Andrew Linden: the "simple collision proxies" solution to the 256 prim car does not solve the border crossing problem
[21:34] Ryozu Yamamoto: It's the asset transfer between regions I think they're having issues with
[21:34] Vincent Nacon: like.... our avatar... it's one physical prim with attachments on
[21:35] Vincent Nacon: oh hmm
[21:35] Ryozu Yamamoto: I'm probably a little off on my wording there
[21:35] Andrew Linden: border crossings block (lag -- rubberband) becuse of a serialization/deserialization problem -- it isn't efficient enough
[21:35] Kitto Flora: Well there is some interest in higher prim count vehicles for use ONLY within one sim.
[21:35] Kitto Flora: But the demand for better sim boundary crossing is relativly huge.
[21:35] Ryozu Yamamoto: I like Francis' answer to border crossings. Lock the vehicle
[21:36] Sidewinder Linden: kitto - would using sculpties be at all reasonable in solving some of those vechicle build issues ?
- a way to do what you want within the 31 prim limit?
[21:36] Andrew Linden: at the moment sculpties don't collide correctly
[21:36] Ryozu Yamamoto: Once uncompressed texture upload works right, that'd be easier >_<
[21:36] Ryozu Yamamoto: That too
[21:36] Vincent Nacon: oh?
[21:36] Andrew Linden: I think they collide like a box, or maybe a torus
[21:36] Sidewinder Linden: well true
[21:36] Sidewinder Linden: ok
[21:36] Vincent Nacon: aren't they still sphere based?
[21:36] Kitto Flora: Sidewinder - Most body builders I have asked say that sculpties are not good for the shapes in vehicle bodies.
[21:36] Ryozu Yamamoto: Elongated sphere, I thought?
[21:36] Sidewinder Linden: they don't collide as the shape they appear to be...
[21:36] Tiberious Neruda: a sphere-ish object, last I heard
[21:37] Tiberious Neruda: right
[21:37] Kitto Flora: I think for an animal vehicle they should be good
[21:37] Andrew Linden: yeah, Qarl Linden said it was a torus, and I bowed my head and cried.
[21:37] Ryozu Yamamoto: I dunno, ESC made a rather nice sculpty car
[21:37] Tiberious Neruda: LOL
[21:37] Vincent Nacon: muhahahaha!
[21:37] Ryozu Yamamoto: lol!
[21:37] Vincent Nacon: nice quote to save on
[21:37] Sidewinder Linden: i'm thinking that if you think carefully about *where* the sculpties are used, you might take some complex details and reduce thme
[21:37] Andrew Linden: One of the projects I want to work on eventually is better collision proxies for sculpties
[21:38] Tiberious Neruda: oh... someone talked briefly about a different kind of sculpted prim, one that could be made flexible
[21:38] Sidewinder Linden: in a way that doesn't make collisions noticeably weird...
[21:38] Ryozu Yamamoto: There's the ESC sculpty hover-car
[21:38] Sidewinder Linden: whoa
[21:38] Sidewinder Linden: kewl
[21:38] Tiberious Neruda: based on a tube shape instead of a sphere. What's latest on that?
[21:38] Andrew Linden: in fact... I kinda NEED to solve the sculptie collision shapes if I'm going to implemnent the object- parcel collision query
[21:38] Ryozu Yamamoto: Tiberious: I think Quarl was talking about using the alpha channel for that
[21:38] Vincent Nacon: want a seat Lina?
[21:39] Lina Lageos: no thanks.....stretching :)
[21:39] Vincent Nacon: ah ok
[21:39] Ryozu Yamamoto chuckles
[21:39] Kitto Flora: Well, what it comes down to is that one can make ok vehicles within the 31 prim count, BUT border crossing is hazardous and slow. I can take out most of the hazard. The slow kills multi-vehicle trains.
[21:39] Ryozu Yamamoto: I do not envy your job, Andrew ;)
[21:39] Tiberious Neruda: that would solve a huge headache that furry av designers have been dealing with
[21:39] Andrew Linden: Oh it is fun... just too much work to do in too short of time.
[21:39] Ryozu Yamamoto: I don't work on salary, nor wages, so I know that feeling
[21:39] Sidewinder Linden: are there any other categories of problmes that you are seeing on havok4?
[21:40] Ryozu Yamamoto: Every hour I'm not working on making money, I make less ;_;
[21:40] Tiberious Neruda: currently, for flexible tails, they've been putting several flexible prims together and using alpha textures
[21:40] Ryozu Yamamoto: Avatar rotations
[21:40] Andrew Linden: Vehicles, avatar motion, some LSL push/force calls, avatar rotations
[21:40] Ryozu Yamamoto: Are you guys familiar with the problem there?
[21:40] Kitto Flora: Me - not yet. SVC-756 kinda steimied further testing.
[21:40] Andrew Linden: Yes, the avatar rotation problem is known
[21:40] Sidewinder Linden: ryozu - which specific problem?
[21:40] Ryozu Yamamoto: AV rotations on the X and Y axis
[21:40] Sidewinder Linden: ok
[21:40] Ryozu Yamamoto: They shouldn't happen, but they do
[21:41] Tiberious Neruda: hmm?
[21:41] Ryozu Yamamoto: Hence the sinking into the ground issue
[21:41] Andrew Linden: ah
[21:41] Andrew Linden: I think I know what is going on there... sorta.
[21:41] Ryozu Yamamoto: The way I understand it, the avatar is an elongated sphere. When rotated on the X or Y axis, the sphere "leans over" and with the avatar's pelvis tied to the center of the sphere, it brings the avatar down
[21:42] Andrew Linden: I've noticed Havok4 disable the inverse inertia hack we did on avatars to keep them upright
[21:42] Vincent Nacon: oh yeah, I've posted a Jira issue bug with the ground slope being high/deep where physical objects can tend to slip through when stacked with other objects
[21:42] Ryozu Yamamoto: While this is NOT the only way it can happen, you can force it. Go into mouselook, Look at the ground, then move forward
[21:42] Ryozu Yamamoto: Exit mouselook, and you'll be rotated
[21:42] Andrew Linden: but I'm not sure when exactly it is happening
[21:42] Ryozu Yamamoto: Well, there's one
[21:42] Andrew Linden: oh, mouselook does it? Ok, good to know.
[21:42] Ryozu Yamamoto: But it also happens on just about any physics collision
[21:43] Ryozu Yamamoto: It's not explicitly mouselook, hence why you have to -move- to make it happen
[21:43] Ryozu Yamamoto: Oh dear
[21:43] Andrew Linden: sigh... one of the problems with such a list of problems... it makes me anxious
[21:43] Andrew Linden: to leave the office hour and go back to work
[21:43] Ryozu Yamamoto: I'm anxious as can be, my #1 seller is busted
[21:43] Ryozu Kojima: ^_^
[21:44] Sidewinder Linden: hehe
[21:44] Tiberious Neruda: actually, this is a good thing
[21:44] Kitto Flora: Me to...
[21:44] Kitto Flora: But I'm sure Andrew will fix it
[21:44] Tiberious Neruda: how long has the populace here wanted a better physics engine? Years?
[21:44] Sidewinder Linden: do we have any other items to talk about?
[21:44] Vincent Nacon: glad I didn't finish my car yet
[21:44] Vincent Nacon: been working on it for a year now
[21:44] Ryozu Yamamoto: The thing is, I know what's breaking it, and I'm sure you guys know as well... I'm acutely aware that Havok4 won't be 100% like Havok1, so I'm worried about what -won't- be fixed... by choice
[21:45] Sidewinder Linden: or have we captured the open list that we've all found so far.. (understanding that there are a lot of things in pjira)
[21:45] Andrew Linden: yes, there may be some things that are not fixed "by choice"
[21:45] Ryozu Yamamoto: That about sums up my concerns though ^_^
[21:46] Andrew Linden: the choice being... take forever to fix it, or get the thing out the door
[21:46] Ryozu Yamamoto: Hehe
[21:46] Vincent Nacon: willing to make changes
[21:46] Tiberious Neruda: oh... when do you plan to do away with the .1m tolerance?
[21:46] Andrew Linden: the Havok4 project was a two month project that has taken almost 12
[21:46] Ryozu Yamamoto: I totally understand though,
[21:46] Andrew Linden: the 0.1m collision tolerance is an intrinsic aspect of Havok
[21:47] Andrew Linden: there are ways to reduce it, and hide it
[21:47] Tiberious Neruda: I have some objects that I built with the intent of having real collisions added....
[21:47] Andrew Linden: but it cannot be totally removed until Havok implements it out
[21:47] Ryozu Yamamoto dreams of better working billiards tables.
[21:47] Vincent Nacon: or code it out
[21:47] Kitto Flora: You have to get used to 4 inches of oil in the bearings.
[21:47] Vincent Nacon: it's open sources for you guys
[21:48] Andrew Linden: it may be possible to reduce the collison tolerance, and take more steps of the physics engine per second
[21:48] Ryozu Yamamoto: Vincent: True to some extent, but keep in mind, we don't want them to rewrite it from scratch either
[21:48] Tiberious Neruda: take a look at this, for instance
[21:48] Andrew Linden: but I've punted testing that stuff until after Havok4 is declared complete enough to deploy
[21:48] Vincent Nacon: pftt just tweak the number a bit
[21:48] Vincent Nacon: ;)
[21:49] Ryozu Yamamoto: lol, if only
[21:49] Sidewinder Linden: i have a question for the group...
[21:49] Vincent Nacon: of course.... haven't seen the source
[21:49] Vincent Nacon: I've seen Havok 1 though...
[21:49] Tiberious Neruda: (now, after resizing it, it lays a little better)
[21:49] Sidewinder Linden: do you all think the damping and "bounce" of collissions, for instance when things drop and hit the terrain or another object, are about right on havok4?
[21:50] Vincent Nacon: not quite
[21:50] Sidewinder Linden: any ocmments on what's good and what's not in that department?
[21:50] Ryozu Yamamoto: Sidewinder: About right in replicating old behaviour? Not really... However, most people on the Beta grid Like it
[21:50] Vincent Nacon: but it would be nice to make our own "materials"
[21:50] Sidewinder Linden: ahh
[21:50] Ryozu Yamamoto: Ah, indeed
[21:50] Tiberious Neruda: yeah...
[21:50] Ryozu Yamamoto: The material property on prims appears to have no effect
[21:50] Sidewinder Linden: so ryozu - in other words <> havok1, but better because it's different?
[21:51] Sidewinder Linden: well better because it feels better or is more realistic?
[21:51] Ryozu Yamamoto: If you guys added different values for each material, I think most people would be qutie happy
[21:51] Ryozu Yamamoto: It "feels better"
[21:51] Vincent Nacon: aywe
[21:51] Sidewinder Linden: kk
[21:51] Vincent Nacon: aye*
[21:51] Ryozu Yamamoto: People like bouncing stuff, hehe
[21:51] Ryozu Yamamoto: right now, most people equate it to rubber
[21:51] Vincent Nacon: yeah, not enough rubber there
[21:51] Tiberious Neruda nods. "better than trying to fake it with scripts"
[21:51] Ryozu Yamamoto chuckles
[21:51] Vincent Nacon: and mass!
[21:51] Ryozu Yamamoto: Mass?
[21:51] Tiberious Neruda: oh!
[21:52] Tiberious Neruda: there's something I noticed
[21:52] Ryozu Yamamoto: Oh, you mean material affecting mass?
[21:52] Vincent Nacon: yeah, apply your own mass, ignoring the size of the prim
[21:52] Ryozu Yamamoto: Hmm, I don't see that happening
[21:52] Vincent Nacon: well not quite
[21:52] Andrew Linden: it might eventually
[21:52] Vincent Nacon: alrighty
[21:52] Tiberious Neruda: if you hollow out a sphere, it ceases to have the nice collision....
[21:52] Ryozu Yamamoto: Hmm, yeah
[21:52] Andrew Linden: I think mass/friction/restitution (bouncyness) could become per-prim settings -- sliders
[21:52] Ryozu Yamamoto: Also, inverted spheres still act non-sphere-like
[21:52] Kitto Flora takes alook at how a rubber sphere bounces...
[21:53] Andrew Linden: but there is a bit of work to do to make that possible
[21:53] Kitto Flora: It seems to embed in the ground
[21:53] Ryozu Yamamoto: Andrew: That would be great, sliders
[21:53] Sidewinder Linden: ... future ;)
[21:53] Tiberious Neruda: but major kudos to fixing the twisted sphere 'blitz' exploit
[21:53] Vincent Nacon: and able to set from LSL
[21:53] Ryozu Yamamoto: Oh yes
[21:53] Andrew Linden: at the moment, I think it is impossible in Havok4
[21:53] Ryozu Yamamoto: Shhhh
[21:53] Vincent Nacon: since when?
[21:53] Andrew Linden: Havok4 does not make it easy to do per-prim (per-shape) friction/restitution settings
[21:54] Andrew Linden: but the mass and inertia can be controlled
[21:54] Ryozu Yamamoto: maybe havok5?
[21:54] Vincent Nacon: hmm
[21:54] Ryozu Yamamoto: Hmm, intertia eh?
[21:54] Ryozu Yamamoto: Even that would be kind of cool
[21:54] Andrew Linden: I think it can be done... but per-shape material settings are not in the default feature set of Havok4
[21:54] Tiberious Neruda: mass could work
[21:54] Ryozu Yamamoto: That could kind of fake bounciness maybe?
[21:54] Vincent Nacon: unless you want to make your own friction/restitution source?
[21:54] Andrew Linden: you would have to write some very special code to get it done
[21:54] Kitto Flora: Bounces - looks like a damped sine wave around ground position, rather than a full-wave-rectified wave
[21:54] Tiberious Neruda: being able to set different ball weights would be nice
[21:55] Andrew Linden: the good news is that Havok4 has lots of hooks for adding custom code
[21:55] Vincent Nacon: such as?
[21:55] Sidewinder Linden: ok... so before we go way in to the stratosphere of new features... have we covered the issues with the current preview? ;)
[21:55] Vincent Nacon: I think so
[21:55] Ryozu Yamamoto: I can't think of anything else
[21:55] Andrew Linden: Sidewinder, sounds like we've got enough issues to keep my busy for a while
[21:56] Sidewinder Linden: uh huh
[21:56] Tiberious Neruda: Andrew, before you get outta here...
[21:56] Ryozu Yamamoto: Add hover-vehicle air friction/intertia issues to the vehicle list in case wasn't already
[21:56] Vincent Nacon: unless those features are really more of a issue in long awaited desire ;)
[21:56] Tiberious Neruda: yeah
[21:56] Andrew Linden: sorry, could you repeate that? or reword it?
[21:57] Vincent Nacon: oohh one thought about the water
[21:57] Ryozu Yamamoto: Me or Vince?
[21:57] Andrew Linden: was that a request for more VEHICLE flag settings?
[21:57] Ryozu Yamamoto: An, no
[21:57] Ryozu Yamamoto: Grab a copy of the Dominus Shadow and go into Hover mode
[21:57] Ryozu Yamamoto: In Havok4, it keeps going, like playing Asteroids
[21:57] Ryozu Yamamoto: In Havok1, it damps, and eventually stops moving
[21:58] Andrew Linden: oh ok. That sounds like a bug
[21:58] Andrew Linden: the hover + linear deflection features can pump energy into the vehicle
[21:58] Ryozu Yamamoto: I'm not at all familiar with vehicle flags, so not sure where the problem is
[21:59] Kitto Flora: I'm playing frizzbee on H4 - it bounces ... interestingly. Different from H1
[21:59] Vincent Nacon: one thing about the water.... maybe give them dense? like how you throw a ball across the water should bouce at first and slowly come down to sinking?
[21:59] Ryozu Yamamoto: But I wanted to mention it, since a lot of attention was paid to ground vehicles, but perhaps not hover types
[21:59] Andrew Linden: interactive water is a feature --> post Havok4
[21:59] Ryozu Yamamoto: =D
[21:59] Vincent Nacon: like an actual friction I guess
[21:59] Andrew Linden: yeah, I haven't tested hover much
[21:59] Ryozu Yamamoto: Buoyancy
[21:59] Vincent Nacon: ahh good then
[21:59] Ryozu Yamamoto: Another would be lovely feature
[22:00] Ryozu Yamamoto: That is to say, automatically set buoyancy when in water
[22:00] Andrew Linden: I don't think I'm going to be able to keep these Tuesday 21:00 office hours
[22:00] Andrew Linden: I think I'm going to have to move them to 16:00
[22:00] Ryozu Yamamoto: I was a bit confused by the hour anyay
[22:00] Tiberious Neruda: sounds good
[22:00] Vincent Nacon: alright.... one last question.... physical particle?
[22:00] Ryozu Yamamoto: thought, "Huh? Office hours, outside business hours? Is that right?" =P
[22:01] Andrew Linden: physical particles... require physics on the client
[22:01] Ryozu Yamamoto: Vince: Probably not, that'd be client side I think
[22:01] Vincent Nacon: true..
[22:01] Kitto Flora: 1600 is a problem
[22:01] Andrew Linden: particles are a client-only special effect -- the simulator knows nothing about them
[22:01] Kitto Flora: 1700 - can arrive late
[22:01] Vincent Nacon: well I guess that's all for today
[22:01] Sidewinder Linden: would 17:00 work for you andrew?
[22:01] Andrew Linden: however... at the moment the client has zero physics in its codebase
[22:02] Ryozu Yamamoto: Thanks Andrew, Sidewinder, I feel a LOT better having the chance to air my concerns. You guys are cool
[22:02] Andrew Linden: 17:00 tuesday doesn't work for me
[22:02] Sidewinder Linden: kk
[22:02] Vincent Nacon: hmm unless you can use ODE for the particles
[22:02] Sidewinder Linden: yw ryozu
[22:02] Andrew Linden: I might be able to do 16:30 - 17:30
[22:02] Tiberious Neruda: well, considering the client's open-source now, someone could probably code enough into it so that would work
[22:02] Sidewinder Linden: we are trying to get this one as close to right as possible - we know it affects a *lot* of content...
[22:02] Ryozu Yamamoto: Perhaps just enough for particles, but who knows
[22:03] Andrew Linden: yes Tiberious, but that is a big project
[22:03] Ryozu Yamamoto: I'd email the SLDev list
[22:03] Andrew Linden: I think it will happen eventually... there are some LL developers who want client side physics
[22:03] Ryozu Yamamoto: Not sure any sane person wants to have to keep two different physics engines around
[22:03] Vincent Nacon: heheh
[22:04] Andrew Linden: I'd expect the simulator and client codebases to diverge
[22:04] Ryozu Yamamoto: They almost have to
[22:04] Andrew Linden: and become less and less coupled
[22:04] Sidewinder Linden: ryozu - i've actually talked to several of our dev's about this, and depending how things are handled, it may not be so bad... although certainly one physics engine in both places is easier in some ways
[22:04] Andrew Linden: so it wouldn't really be two separate phys engines... just one, depending on which project you were working on.
[22:05] Ryozu Yamamoto nods.
[22:05] Sidewinder Linden: and it depends how much of which functions are handled in viewer vs server
[22:05] Ryozu Yamamoto: What's the main use case for physical particals anyays Vince? rain?
[22:05] Andrew Linden: ok, i've got to get to bed -- I get up really early
[22:05] Ryozu Yamamoto: Verticaly descending type particles?
[22:05] Ryozu Yamamoto: Alright, G'night Andrew =)
[22:05] Tiberious Neruda: well, rain, Killer Instinct-style particle showers...
[22:05] Sidewinder Linden: thanks andrew, and thanks everyone for helping to test havok4
[22:05] Tiberious Neruda: Andrew, before you go...
[22:05] Vincent Nacon: oh one question for you Sidewinder.... which isn't related to Havok 4.... joystick inputs via LSL?
[22:06] Sidewinder Linden: great great feedback
[22:06] Andrew Linden: yeah, thanks for helping test it out.
[22:06] Tiberious Neruda: can you resurrect this script, by chance?
[22:06] Ryozu Yamamoto: Heh
[22:06] Sidewinder Linden: hehe vincent
[22:06] Sidewinder Linden: well...
[22:06] Vincent Nacon: I had to
[22:06] Andrew Linden: what script?
[22:06] Tiberious Neruda: anytime I try to open it, I get a 'Script is Missing from Database' error
[22:06] Ryozu Yamamoto: It occured to me, if it's only verticle ascent, maybe the same code could be used that particles use for bounce
[22:06] Sidewinder Linden: i've heard a few hallway conversations about that general topic, but i don't think it's on an active development path right now...
[22:06] Ryozu Yamamoto: err, descent
[22:06] Vincent Nacon: ah ok
[22:07] Vincent Nacon: long as someone was talking about it
[22:07] Vincent Nacon: ;)
[22:07] Ryozu Yamamoto: WIth some modification, maybe it can be told to bounce off prims instead of the z axis of particle source
[22:07] Sidewinder Linden: yep ;)
[22:07] Sidewinder Linden: but that doesn't mean feature implementation soon - just to be clear...
[22:07] Tiberious Neruda: and attempting to copy the UUID results in a NULL_KEY
[22:07] Ryozu Yamamoto: You know, the control/takecontrol features of LSL sure do give a lot of ODD results
[22:07] Andrew Linden: in order to bounce off of prims you need collision detection -- for all shapes
[22:07] Ryozu Yamamoto: True
[22:07] Andrew Linden: and maybe even able to handle alpha textures
[22:07] Vincent Nacon: hmm
[22:08] Ryozu Yamamoto: I dunno how it'd be done, but I know I can't do it, heh
[22:08] Ryozu Yamamoto: Just a thought anyways
[22:08] Andrew Linden: that sort of collision detection is different from Havok4 -- maybe in Havok7, they're working on doing more GPU wiz-bang features
[22:08] Vincent Nacon: they're on 7 now!?
[22:08] Sidewinder Linden: hehehehe
[22:08] Andrew Linden: no... just saying: distant future
[22:09] Vincent Nacon: ah :0
[22:09] Sidewinder Linden: ok... so shall we let andrew get some sleep folks?
[22:09] Ryozu Yamamoto: Yep
[22:09] Vincent Nacon: yeah I need sleep too
[22:09] Ryozu Yamamoto: Me, I'm off to play golf
[22:09] Ryozu Yamamoto chuckles
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