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WarKirby Magojiro · 09-18-2008, 06:16 PM

My current project has suddenly hit a big brick wall. Very frustrating.

In short, I'm trying to move some very large (single prim) physical objects, slowly. I have it working up to 10x10x10, but once I get into the megaprims, everything falls apart. And I need to make it work with 30x30x30 at the largest.

The problem, is energy. I was using llSetBuoyancy to keep my object n the air, and it worked fine with the smaller sizes. But now, I'm trying to do a 12x12x12, and it's just too heavy. It flies slowly for about 5 seconds, then suddenly runs out of energy, and drops like a stone.

This is already hollowed out, by the way. Before hollowing, it wouldn't move anywhere but down at all.

I need some creative solutions for holding a large physical object in the air for a fairly long time. Probably up to a minute or so. Can anyone help out?

WarKirby Magojiro · 09-18-2008, 10:52 PM

Can anyone help ?

Aodhan McDunnough · 09-18-2008, 11:30 PM

IIRC megaprims screw up Havok physics. I'm not sure if impulse control systems can handle it.

Beezle Warburton · 09-18-2008, 11:31 PM

Trying to get Havok to cope with mega prims may be an exercise in madness. I wish you luck.

Aodhan McDunnough · 09-18-2008, 11:57 PM

I've done a lot of impulse control system programming and if buoyancy is failing you, and I know that impulses are not as powerful as they used to be, I have serious doubts that it can be handled smoothly.

Try an llSetForce(<0,0,9.8>*llGetMass(),FALSE) ... and pray.

Chalice Yao · 09-19-2008, 05:00 AM

I think Dan Linden posted a 'fix' on the according JIRA to make movetotarget and buoyancy work for bigger prims (this starts with 5x5x5 already at times)

llApplyRotationalImpulse(<0,0,0>,0,FALSE);

I'm not sure if it has to be called repeatedly or not.

WarKirby Magojiro · 09-19-2008, 11:27 AM

Oh, wow, good results so far. Aodhan's suggestion makes it work - for 12x12x12 at least . We'll see how it fares with larger sized. If this doesan't work, I'll try the rotational impuilse

WarKirby Magojiro · 09-19-2008, 11:35 AM

Yay

llSetForce is working even for the 30x30x30 . Not only that, it works entirely perfectly. Using llSetBuoyancy before, it was slowly sinking even at 10x10x10. Now there's no sink at all, and it can actually fly upwards
This is awesome. Thank you Aodhan

Aodhan McDunnough · 09-19-2008, 11:50 AM

Quote:

Originally Posted by WarKirby Magojiro

Yay

llSetForce is working even for the 30x30x30 . Not only that, it works entirely perfectly. Using llSetBuoyancy before, it was slowly sinking even at 10x10x10. Now there's no sink at all, and it can actually fly upwards
This is awesome. Thank you Aodhan

Oh wowie! I've never even rezzed a mega before. Thanks also for the feedback so at least if I ever have to do what you're doing I know what works.

In essence the function I gave you is a gravity canceller. I have no idea what its limits are in havok 4.

Aaron Edelweiss · 09-19-2008, 01:10 PM

Sounds like you've got it working, but if you feel like testing another way, you might try making them vehicles. Airplanes specifically. Vehicle buoyancy is different and not as restricted as llSetBuoyancy.

Stickman · 09-20-2008, 04:57 AM

I've had some problems with large prims falling out of the sky after a long period of time. I'd recommend double checking llGetEnergy() and making sure it's not slowly leaking energy and will die after a day or two. If you need it alive that long. It's rare to hit that perfect point, but it's happened to me.

Some good tricks in this thread.

Ben Hoark · 09-20-2008, 05:51 AM

Quote:

Originally Posted by Stickman

I've had some problems with large prims falling out of the sky after a long period of time.

Their orbits are decaying?

Thanks for the formula, Aodhan -- could be useful for something of my own.

Khamon · 09-20-2008, 10:20 AM

Quote:

Originally Posted by Stickman

I've had some problems with large prims falling out of the sky after a long period of time. I'd recommend double checking llGetEnergy() and making sure it's not slowly leaking energy and will die after a day or two. If you need it alive that long. It's rare to hit that perfect point, but it's happened to me.

This is only true for physical megas right?

Aodhan McDunnough · 09-20-2008, 10:25 AM

Thanks to this thread I actually rezzed my first megaprim (evah). It's a 32x32x4 that I just tapered. It's going to be my new flooring for the workshop and maybe the store too, I don't know. Non-physical

YES I'm that boring at times.

WarKirby Magojiro · 09-20-2008, 01:32 PM

I don't need it anywhere as long as a day. It's for the gigantic energy ball I'm making, it will generally have a lifetime of 1-2 minutes, so even if it were slowly leaking energy, this does the job for me

09-18-2008, 11:30 PM	#3 (permalink)
Aodhan McDunnough exp(ln(Gearhead)) lim as x->0 of Geek/x Join Date: Jun 2007 Location: Philippines Posts: 3,727 Beer Tapper Gone Wild Champion! SL Join Date: March 28, 2006 Business: Aodhan's Forge SLShopper Ads: 2 My Mood:	IIRC megaprims screw up Havok physics. I'm not sure if impulse control systems can handle it. __________________ We can't get rid of Landbots but we can stop the damage. VOTE this proposal on the Jira. Current votes: 71 http://jira.secondlife.com/browse/VWR-2905 Kontours Classic 1-prim chair. Sculpted, menu controlled http://www.sluniverse.com/php/shop/s...ct=786&cat=500

09-18-2008, 11:31 PM	#4 (permalink)
Beezle Warburton Stabbity! GAH! Join Date: Aug 2007 Location: Darkmere Posts: 2,539 SL Join Date: October 24, 2006 Business: Cortech Enterprises SLShopper Ads: 13 My Mood:	Trying to get Havok to cope with mega prims may be an exercise in madness. I wish you luck. __________________ Cortech Enterprises Alternate Location Cortech at Shop.OnRez Second Life®, SL®, $L™, Lindens™, Linden Dollars®, Linden Lab®, Missing Image™, [RESOLVED]™ and the color gray are trademarks or registered trademarks of Linden Research, Inc. All rights reserved.

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09-18-2008, 10:52 PM	#2 (permalink)
WarKirby Magojiro Doing stuff Made new armor ^^ Join Date: Sep 2007 Location: Glasgow, Scotland Posts: 2,607 SL Join Date: 14/10/2006 Business: MagoTek Industries SLShopper Ads: 1 My Mood:	Can anyone help ?

09-18-2008, 11:57 PM	#5 (permalink)
Aodhan McDunnough exp(ln(Gearhead)) lim as x->0 of Geek/x Join Date: Jun 2007 Location: Philippines Posts: 3,727 Beer Tapper Gone Wild Champion! SL Join Date: March 28, 2006 Business: Aodhan's Forge SLShopper Ads: 2 My Mood:	I've done a lot of impulse control system programming and if buoyancy is failing you, and I know that impulses are not as powerful as they used to be, I have serious doubts that it can be handled smoothly. Try an llSetForce(<0,0,9.8>*llGetMass(),FALSE) ... and pray.

09-19-2008, 05:00 AM	#6 (permalink)
Chalice Yao The Purple Kinda at work. Somewhat. Join Date: Dec 2007 Location: Somewhere purple, Germany Posts: 1,300 My Mood:	I think Dan Linden posted a 'fix' on the according JIRA to make movetotarget and buoyancy work for bigger prims (this starts with 5x5x5 already at times) llApplyRotationalImpulse(<0,0,0>,0,FALSE); I'm not sure if it has to be called repeatedly or not.

09-19-2008, 11:27 AM	#7 (permalink)
WarKirby Magojiro Doing stuff Made new armor ^^ Join Date: Sep 2007 Location: Glasgow, Scotland Posts: 2,607 SL Join Date: 14/10/2006 Business: MagoTek Industries SLShopper Ads: 1 My Mood:	Oh, wow, good results so far. Aodhan's suggestion makes it work - for 12x12x12 at least . We'll see how it fares with larger sized. If this doesan't work, I'll try the rotational impuilse

09-19-2008, 11:35 AM	#8 (permalink)
WarKirby Magojiro Doing stuff Made new armor ^^ Join Date: Sep 2007 Location: Glasgow, Scotland Posts: 2,607 SL Join Date: 14/10/2006 Business: MagoTek Industries SLShopper Ads: 1 My Mood:	Yay llSetForce is working even for the 30x30x30 . Not only that, it works entirely perfectly. Using llSetBuoyancy before, it was slowly sinking even at 10x10x10. Now there's no sink at all, and it can actually fly upwards This is awesome. Thank you Aodhan

09-19-2008, 01:10 PM	#10 (permalink)
Aaron Edelweiss Banned mmmm, coffee Join Date: Dec 2007 Location: Hillsboro, OR, USA Posts: 430 SL Join Date: 4/4/2004 SLShopper Ads: 1 My Mood:	Sounds like you've got it working, but if you feel like testing another way, you might try making them vehicles. Airplanes specifically. Vehicle buoyancy is different and not as restricted as llSetBuoyancy.

09-20-2008, 04:57 AM	#11 (permalink)
Stickman Junior Member Join Date: Jan 2008 Location: Seattle, WA Posts: 29	I've had some problems with large prims falling out of the sky after a long period of time. I'd recommend double checking llGetEnergy() and making sure it's not slowly leaking energy and will die after a day or two. If you need it alive that long. It's rare to hit that perfect point, but it's happened to me. Some good tricks in this thread.

09-20-2008, 10:25 AM	#14 (permalink)
Aodhan McDunnough exp(ln(Gearhead)) lim as x->0 of Geek/x Join Date: Jun 2007 Location: Philippines Posts: 3,727 Beer Tapper Gone Wild Champion! SL Join Date: March 28, 2006 Business: Aodhan's Forge SLShopper Ads: 2 My Mood:	Thanks to this thread I actually rezzed my first megaprim (evah). It's a 32x32x4 that I just tapered. It's going to be my new flooring for the workshop and maybe the store too, I don't know. Non-physical YES I'm that boring at times.

09-20-2008, 01:32 PM	#15 (permalink)
WarKirby Magojiro Doing stuff Made new armor ^^ Join Date: Sep 2007 Location: Glasgow, Scotland Posts: 2,607 SL Join Date: 14/10/2006 Business: MagoTek Industries SLShopper Ads: 1 My Mood:	I don't need it anywhere as long as a day. It's for the gigantic energy ball I'm making, it will generally have a lifetime of 1-2 minutes, so even if it were slowly leaking energy, this does the job for me