Monday, December 8, 2008

Owen Oyen - Working Sailboat in the OS Grid



[9:00] Owen Oyen shouts: Hello, Folks. I am Owen Oyen. Nice to see all of you with whom I am friends and nice to meet all of you I don't yet know. First, a thank you to Tasha, Iza, Disisme, Liv, RJ and any other AV involved with the very hard work of putting this great SL event together. This is a beautiful venue. [ feel free to applaud and :) ]
[9:00] Gemma Vuckovic: speak up, we cant hear at the back

[9:01] Owen Oyen shouts: I was asked to prepare a talk for the sailing community gathered here today on various subjects of interest to SL and virtual sailing. As I paste it, ask questions at any time. You'll be in my chat buffer. I'll try to catch them all either as I'm pasting or after I'm done pasting. If I do neither, yell. Loudly.



[9:01] Owen Oyen shouts: I build the ACC racing yacht in SL and I introduced it in its 1.0 version about 18 months ago. She was the first boat in SL with a wind shadow and the first boat with a wave motion model. Let me stop myself just a moment here to recognize . . . that this is a situation relevant to the famous Sir Isaac Newton quote "If I have seen a bit further, it is because I stand on the shoulders of giants." My modest contributions to SL sailing follow in the footsteps of Kanker Greenacre's first SL boat. My contributions also would be of little significance were it not for the attraction to sailing derived from the artistry of Jacqui, Verkin and any other sailboat artists who predate me in SL and who . . . I will regret neglecting to mention later.

[9:03] Owen Oyen shouts: Since ACC 1.0's introduction, about 8 months later I introduced rev 2.0, which is parked for show here at this boating event. She, like 1.0, conforms in all dimensions to the IACC 2007 Rules formula. She has a refined wind shadow (the original was somewhat brutal), she has a randomly timed sail damage feature on her that requires a crew member to go aloft and do repairs in order to restore full racing performance, and she responds to tidal current, which I will discuss in a moment.

Owen Oyen shouts: First, I'd like to describe something new going on in another virtual world, namely OSGrid (Open Source Grid, www.osgrid.org). I am not an OSG zealot or recruiter and I'm not going to talk about OSG itself. Instead, I will talk about a sailboat there. That boat was built to provide folks here with options amid the recent pricing upheaval, but this talk is not about sim pricing. It's about boat features and only about boat features. The OSG boat introduces some new approaches to virutal sailing.



9:05] Owen Oyen shouts: Making a sailboat is no longer quite the big accomplishment in virtual worlds that it was when Kanker Greenacre started, but there is one thing different about OSGrid that makes a sailboat challenging there. Namely, OSG is young, and there are no LL vehicle functions implemented (yet). The boat builders here know what that means and what a problem that presents. The usual way of generating simulated propulsion for a virtual world boat, the way that Kanker Greenacre originally did it, is not available in OSG.

Owen Oyen shouts: I hear typing clicks . . yes OSGrid is Open Source sims, outside SL with some talk underway about connecting the grids, but I will leave OSG talk to others

[9:07] Owen Oyen shouts: This forced me (no pun intended) to find a workaround. The key equations for it are on a poster here beside me to my right. They are not complex or revolutionary and I'm obviously giving them away. They involve raw physics, bypassing the standard Linden Lab motor parameters of the ll functions. And . . . for you boat builders, they . . . the equations . . . result in code that is likely to use fewer instructions per second (aka lag) than the llSetVehiclethisorthat appproach. It is an approach to making virtual sailboat propulsion in a different way than usual. I'll pause here a moment so the poster can rez for everyone.

[9:08] Owen Oyen shouts: anyone NOT see the poster yet?

[9:08] Liv Leigh: i don t see you even owen lol

[9:08] Tasha Kostolany shouts: (Larz will be talking further on OS Grid this coming Sunday)

[9:08] Liv Leigh: i see a big grey ball with your name tag
[9:08] Owen Oyen shouts: I'm not worth seeing Liv, but I'll wait a few secs for the folks to see the poster

[9:09] Lazarus Longstaff shouts: Suffice it to say, Owen knows how to make a boat sail by using a pure physical simulation





[9:09] Orca Flotta shouts: if you can't see Owen or the poster you're obviously on some crappy SL viewer :)

[9:10] Owen Oyen shouts: I am sure there are other vehicles here in SL using this kind of technique, but sailing has very special requirements and aspects that other vehicles do not encounter, so this is likely somewhat new for sailing. It will certainly require effort to embrace llSetForce (and llSetTorque to turn) should you wish to. I presently use llSetForce to implement tidal current on the ACC -- and yes, I know the wiki says you can't use llSetForce with "vehicles". I did anyway. It has worked fine for 9 months with no unpleasant side effects at all.

[9:11] Owen Oyen shouts: If you're bored, we're already past the 1/2 way point, so hang in there


[9:11] Owen Oyen shouts: There are some pictures here beside me of the OSGrid boat, and also the iceboat variant we have prepared there.





Bri Hasp has made a pretty ice sim and Hiro Protagonist has laid out some racing buoys in his water sim. About 35 boats have been distributed by the OSG 0L vendor over the past 2 weeks and hopefully people are having fun, despite various Beta issues. Note that all the propulsion is in the ugly yellow prim, and the attachment boat frame (made by Hiro) can be anything any boating artist wishes it to be. Sail commands are documented and publicly available so sails can be rotated.

[9:12] Owen Oyen shouts: arggg, forgot to get iceboat pics, they are at OSGrid sim Sailing, an ice sim, if you visit

[9:12] Owen Oyen shouts: Before I shut up, one more thing. Tidal current. About a year ago Soro Dagostino suggested to me that an AV named seonaid McLean had an idea for sailing and wanted to talk about it. Tidal current in SL was her idea. Not mine. What we did was map the terrain of selected sailing areas, port the terrain map to Scotland (seonaid's home) and we then ran a fluid dynamics model against that terrain to predict how RL water would flow on a race course. This current model is dependent on the terrain of the shorelines, a predefined direction of predominant flow (which will eventually be time of day dependent) and the sim seafloor shape. The numbers are not "faked".

[9:13] Owen Oyen shouts: SL boats equipped with the protocol transmit their position and velocity to the model in Scotland. The model presumes a certain number of seconds will elapse for the transmission to and from Scotland and based on that number and boat velocity vector, we project the boat's position ahead to where it will be when the numbers from Scotland arrive back in SL. We inform the boat of the tidal current at that locale and the boat's scripts respond to it and slow the boat down, speed it up, or push it sideways. Just like RL. haha Scotland has very strong tidal current and seonaid persuaded me that 4-6 knot current in Manning Strait would be fun. She has proven to be correct.



[9:14] Pensive Mission shouts: not for sailors who can't go faster than 3m/sec

[9:14] Owen Oyen shouts: haha Pensive, you'll get better
[9:14] disisme Misfit: the boat might not tho...

[9:14] Owen Oyen shouts: Tidal current maps are available here:

[9:15] Nomad Zamani: I'm from Scotland in RL, and I *have* sailed backwards while making good way through the water. ;)

[9:15] Lazarus Longstaff shouts: some boats just shouldnt be sailed in some bodies of water
[9:15] Frank Marder shouts: try the detroit river

[9:15] Owen Oyen shouts: Sailor's Cove Northern Race Courses
http://img522.imageshack.us/my.php?image=croppedsccurrentmapiq6.jpg

[9:16] Owen Oyen shouts: Ppl, please, boats were made to go FORWARD

[9:16] Owen Oyen shouts: Mowry Bay Course
http://img527.imageshack.us/my.php?image=chartimagewithtextoq4.png
[9:16] disisme Misfit: ahuh..its like a tiger moth with a 60 knot headwind....
[9:16] disisme Misfit: hovering at full throttle
[9:17] Owen Oyen shouts: All the maps just pasted are *SL*
[9:17] Owen Oyen shouts: Please note, we DO intend to support the same feature in OSGrid. There is a slight advantage there in that all sim terrain.raw files are easily available, so no tedious mapping process is required.

[9:18] Owen Oyen shouts: The ACC is equipped with this scripting. So is Mothgirl Dibou's Fizz, and her new current approach I am told can interface with the tide model, as her previous Fizz did. The protocol for communicating with seonaid's server and receiving the real time tidal current numbers is free to any boat builder who wants to use it. We are doing this for fun and there is no business model. If you enjoy it, IM seonaid and thank her. Since we started tidal current support . . . over a period of 9 months now, I think seonaid's server has been offline for perhaps a total of 15 days. She fixes things when they go wrong. It's been reliable. When her server is not there, the boats just sail with 0 current. This has been rare.

[9:18] Liv Leigh takes another pic of owen the grey

[9:19] Owen Oyen shouts: And now, the moment you've all been waiting for
[9:19] Owen Oyen shouts: Time for me to shut up. Thanks for your polite attention.
[9:19] Owen Oyen shouts: Questions?

[9:19] Liv Leigh: thanks!
[9:19] Nomad Zamani: Thank you, Owen. :)
[9:20] Caf Binder: Thanks
[9:20] disisme Misfit: everyone, lazarus is loitering in the background here..he is an OSGrid admin and will be presenting on it this sunday

[9:20] Tasha Kostolany shouts: give us a second to think of some questions Owen
[9:20] Lazarus Longstaff shouts: GREAT JOB, OWEN!!
[9:20] Frank Marder shouts: and thank for for clarifying issues about the osgrid.com
[9:20] Lazarus Longstaff shouts: osgrid.org

[9:20] Owen Oyen shouts: Waiting a bit, and there ARE permissions there, but they require thought. Others will address this

[9:20] disisme Misfit: Can I make one point to everyone here.....
[9:21] disisme Misfit shouts: yesterday it was discovered that there had been a change made on OSGrid that rendered the boat physics...dysfunctional......
[9:21] Lazarus Longstaff shouts: LOL that has already been corrected
[9:21] disisme Misfit shouts: to OSGrids credit, that change was backed out overnight....
[9:21] Liv Leigh: you re too efficient
[9:21] Owen Oyen shouts: That was fixed this morning, Dis, in case folks from this talk visited
[9:21] Lazarus Longstaff shouts: not backed out - fixed
[9:21] disisme Misfit shouts: this is something you will NOT see Linden Labs EVER do
[9:21] Kalle Lannock: So bugs are fixed overnight compared to never by LL ;)
[9:21] disisme Misfit shouts: ok...fixed..same thing, really :)
[9:22] disisme Misfit shouts: Lindens have a "oh..thats bad luck" support methodology....
[9:22] disisme Misfit: OSGrids responsiveness is... immeasurably ebetter



[9:22] Owen Oyen shouts: I am not here to trash LL. The OSG response to the error yesterday was great

[9:23] Lazarus Longstaff shouts: I dont want to trash LL either - this couldnt have been done without their generous contribution of their proprietary network protocol specifications

[9:23] Liv Leigh: what do you think your findings in os grid could mean ported back to SL?

[9:24] Owen Oyen shouts: Liv, good question. The llSetForce formula SHOULD help boat builders build lower lag boats, even if they don't use llSetForce. The velocity setting feature / technique really saves time tweaking settings to get a particular speed at a particular polar angle
[9:24] Lazarus Longstaff shouts: <== is Hiro Protagonist on OSGrid, and one of several OSGrid admins [9:24] disisme Misfit shouts: I'd like everyone to put a quick note of their thoughts about this presentation in a notecard and send it to me [9:25] Liv Leigh: so we can safely say you reinvented the sailboat? [9:25] Lazarus Longstaff shouts: reengineered? [9:25] disisme Misfit shouts: jiggered with? [9:25] Lazarus Longstaff shouts: ripped and reconfigged? *GRINZ* [9:26] disisme Misfit shouts: frikked around with? [9:26] Owen Oyen shouts: No, Liv. I invented a way to work around limits, and someone else would have done it the same way had they been there. It is NOT SL quality of sailing, but . . . it's a lot cheaper [9:26] Liv Leigh: it s always been emulated physics yes [9:26] Lazarus Longstaff shouts: like anything, it can (and will) be improved over time [9:26] Liv Leigh: ic, but.. i reckon it does offer us a long-term perspective in making boat scripts mroe efficient? in os grid but also here 9:27] Lazarus Longstaff shouts: the thing that broke steering briefly was a fix that is already ten new steps in the right direction [9:27] Liv Leigh: allowing more boats, larger boats, whatever [9:27] Owen Oyen shouts: possibly, Liv, I think you can cut down on some things in SL vehicles and less load on CPUs is less lag [9:27] Liv Leigh: or just better sim performance [9:28] Owen Oyen shouts: Okay, thank you all for coming. I must return to RL. Thanks to the great venue set up by the boat show team, too. Everyone Have Fun!! [9:28] disisme Misfit: oh..and Owen....I look like this in your honor today....you expected a clothes change x 4....so I tossed a skin in for fun [9:28] Tasha Kostolany shouts: THANK YOU OWEN, YOUR THE BEST [9:28] Owen Oyen shouts: bye all [9:28] Owen Oyen is Offline [9:29] disisme Misfit: poof..gone [9:29] Sillygirl Beningborough: thanks! [9:29] nobuko Criss: WOOOOOT!!!! [9:29] xnobuko Criss: (ja->en) WOOOOOT!!!!

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