Why Does A Teleporter Disappear?

[Prokofy Neva]

I've gotten used to the phenomenon over the years in SL where teleporters disappear after you arrive on them. Then after you step off, in a minute they may re-appear. To me, this is just "normal behavior" but even if they temporarily disappear, they are still "there" and you see them again in time to use them.

But now I have one that is just disappearing for good. I keep putting out out, over and over, and it just poofs after one use.

I don't know if this is something about a graphics card rendering or actually the fact that teleporters move across sims (that's one of the ways they function, anyway). I have observed how they do this examining the Fnordian teleporter -- in fact in one case where it has to cross a sim through a Linden road it jams and returns if you use that mode.

So I assume that the reason teleporters disappear is that they get stuck moving or something else is happening to make them not render.

I have contacted the maker of this other teleporter about why it is disappearing but I have definitely documented that it does completely disappear -- and for good.

o This is not a return to lost and found due to group land issues. The group is correct, the prim is set, and this very type of teleporter used to "stay put" when rezzed and when used multiple times.

o When I click the destination, I already see it disappear and photograph it.

o When I land, the other one disappears and now with both gone, I can't use them to get back.

o Using area search, there is no evidence of them at all.

o Using searchbert, which scans an area for items by name, there is no finding them.

o They aren't offworld, they aren't in the sim trash, they're just gone.

But why?

FWIW, this started happening after this change:

[15:39] Second Life: The region you have entered is running a different simulator version.
Current simulator: Second Life Server 16.08.31.319299
Previous simulator: Second Life RC LeTigre 16.09.14.319788

 

i.e. after the most recent Linden patch. Thoughts?

 

[Qie Niangao]

Hmm. I expect we could figure out a workable teleporter for this application, but to answer the immediate question, there's a report that something rather dire has happened to script performance in the new RC sim version, 16.09.14.319788. I haven't had a chance to test this further myself.

[Rolig Loon]

That's a complex question, hard to answer because there are many ways to write teleporters, and they don't all work the same way.  For example, many units that are meant to move you from one place to another in the same region are some sort of "sit teleporter," whether you actually sit on them or not.  One standard design follows the pattern:

1. sit on object

2. object moves to new location

3. object forces you to stand up.

That's simple enough, but what happens to the object? We can't have it littering the region.  Some teleporters are designed to go back to where they started.  Others are designed to vanish, perhaps to be replaced at the original spot with a newly rezzed one or perhaps just designed to be throwaways.

Another standard model follows the pattern:

1. sit on object but ....

2. the object's sit target is actually up to 300m away, so you actually are already at your destination

3. object forces you to stand up

With that kind of teleporter, the unit never goes anywhere.  You do. (I made one a long time ago that teleports you to wherever your camera's focus is.  Very handy.)

There are many variations on those models and on systems that use your map view or llTeleportAgent, which is most useful if you happen to be in an experience.  Teleporters can be scripted to animate you so that you never appear to be sitting, or to involve particles and other diversionary slight of hand so that you can't tell what teleported you.  Teleporters are often scripted with fixed destinations, but can be designed to be moveable (I have sold one like that for a few years now).

So how do teleporters fail?  Sometimes they fail if they send you to someplace that they are not allowed to go, or across a region boundary, where they have a hard time getting back.  If you accidentally mistype the destination or it's return spot when you set up a teleporter, it could be almost anywhere.  Unfortunately, area search and pathfinding >>> linksets don't always find everything you would like them too either, so they can miss things that are in plain sight.  I have lost track of countless teleporter-like objects.  God only knows where they went.  I rez a new one and vow to be more careful next time.

[Prokofy Neva]

Rolig, believe it or not, I know all that. You know why? Because I studied the different options or modes of teleporting that Fnordian offers, and also discussed it with the Fnordian guy so I could understand it better. And I said that in my OP. There's this way and that way and yet another way -- one is more speedy and optimal blah blah.

And truly I get it that a) the things physically move and/or b) they re-rez a new one.

But...usually they don't DISAPPEAR FROM THE FACE OF THE EARTH. 

THAT is the question.

Something is breaking down, and I suspect it's the channel/new patch/whatsis that is causing this because that's the factor that changed. I'm going to try to find a Le Tigre channel or whatsis and test it there and see if this does NOT happen which would help isolate it.

It's not about mistyping destinations.

It's about the TELEPORTER OBJECT ITSELF DISAPPEARING. Believe me, I checked the destinations a hundred times. I had copies of my original item that worked because I had plans to expand. It's when I came back and started trying to put out those copies I found the problem. They were copies of a system that originally worked with the destinations intact and working properly.

Searchbert with its 168 meters or what-have-you is not going to be wrong. For example, it found some much older versions of this TP that rezzed under a skybox that had physics before I propped it up with a prim board. 

Area search I don't believe in fully for very basic reasons, but it's good enough.

You can't "rez a new one" in this case because dozens of re-rezzed ones over several days are ALL going missing. So this is not the fix.

 

[Prokofy Neva]

OK, confirmed:

When I go on a Le Tigre sim and rez these teleporters and put in destinations, they work fine, they don't disappear, I tried them a half dozen times, they stayed put and put me exactly where I had indicated in the destination.

This is the kind of thing it is:

You are at 183.2, 22.6, 42.1 in Alston located at sim10371.agni.lindenlab.com (216.82.51.21:13012)
SLURL: http://maps.secondlife.com/secondlife/Alston/183/23/42
(global coordinates 261,815.0, 257,303.0, 42.1)
Second Life RC LeTigre 16.09.14.319788

 

When I go to this OTHER sim which doesn't have Le Tigre but "Second Live Server" the teleporter DOES disappear, over and over.

You are at 128.0, 134.9, 38.3 in Carlisle located at sim10719.agni.lindenlab.com (216.82.53.81:13002)
SLURL: http://maps.secondlife.com/secondlife/Carlisle/128/135/38
(global coordinates 262,272.0, 257,159.0, 38.3)
Second Life Server 16.08.31.319299

I could add that Alston had the problem of the disappearing teleporters a few weeks ago, maybe the channel was different.

This seems like a serious bug, making scripted items disappear like that.

[Prokofy Neva]

One other thing I determined in testing these different teleporters, with the Fnordian creator who made a house call  -- object entry has to be checked off, i.e. has to be functioning for the teleporter to work with RegPos. 

So in Alston with Le Tigre, the reason one teleporter wasn't working was simply that object entry was unchecked on one of the parcels. So once I checked that it worked.

However, the original problem sim (Carlisle) has object entry for both everyone and group checked, so that wasn't at issue....

[Dora Gustafson]

It is not clear to me if the teleporter goes back to start after use

IF it does AND the old warp hack is used it may get caught over a parcel that do not allow object entry

Solution: Replace warp with the modern llSetRegionPosition

:smileysurprised::smileyvery-happy:

[Qie Niangao]

---

Prokofy Neva wrote:

When I go on a Le Tigre sim and rez these teleporters and put in destinations, they work fine, they don't disappear, I tried them a half dozen times, they stayed put and put me exactly where I had indicated in the destination. ... 

When I go to this OTHER sim which doesn't have Le Tigre but "Second Live Server" the teleporter DOES disappear, over and over.

---

Unfortunately, it's the RC sims such as Le Tigre that got the possibly problematic update I mentioned above, so that doesn't explain this problem.

I like Dora's identification of warpPos as a possible culprit. I'm assuming "Fnordian" teleporters aren't open source, but if the creator is in contact, it's definitely time to switch-out any remaining warpPos for llSetRegionPos(). And if warpPos isn't still in the script, it would help to get some debug code in there and find out where it's getting stuck.

[Prokofy Neva]

No, it's not about warpPOS at all, that was NEVER the issue.

Fnordian has different modes you can select. I always select regPOS and that is what is on now.

His teleporters are NOT the one disappearing. Once I got rid of the unchecked object entry on the LeTigre sim, the problem stopped where it was disappearing and reappearing on top of the destination TP. So that is unrelated to the Linden update.

It's another maker, OTR that is disappearing not on the LeTigre sim, but the other one, even when object entry is checked off, i.e. functioning.

[Prokofy Neva]

The teleporter doesn't go back to start after use -- it DISAPPEARS completely. It's nowhere. Nowhere.

There is no "object entry" issue on this other sim with this other maker.

Again, "warp" was not the issue either as it is on the regPOS setting.

[Innula Zenovka]

Sometimes when objects disappear on me, I've found them either at <0.0, 0.0, 0.0> on the region (or as close to it as they can get, often buried under the ground) but not showing up in either Build>Pathfinding>Linksets or World>Region/Estates>Debug>Get top scripts.     Sometimes, indeed, they appear to have managed to get just over the border into the neighbouring region, even though that's not supposed to be possible.

That could be where they're ending up.   Worth looking if you haven't already done so.

Or... the scripter might have put in some error-handling routine whereby the teleporter deletes itself if it doesn't return home in a timely manner.   But that, of course, doesn't explain why it's not getting home in the first place.

[Prokofy Neva]

No. They are not in the "sim trash" (0.0.0).

They are not underground.

They aren't anywhere.

They're gone.

You can't get the menu "get top scripts" on *MAINLAND* sims, only the Lindens could do that, so eventually one could put in a ticket but the issue is not where they went; the issue is that they disappear because of the Lindens' software.

I realize that's a shocking concept, but I think all indications are that it's not about the script in the object or some other factor but the Lindens' software.

I can't emphasize it enough: if something worked for weeks on end on the Le Tigre channel with the previous software version, then...it doesn't have an error-handling routine gone awry. Because, you know, it's working.

Sims can have lag and issues after restart and blah blah blah, but if the item WORKS for weeks on end, and there isn't issues where it sometimes disappears due to lag or whatnot, then, you have to look elsewhere for the problem.

The fault, dear Brutus, is not in ourselves, for we are underlings, but in our stars...

If it DOES NOT disappear for weeks on end UNTIL the software changes then -- gasp -- it must be the software.

I realize many people want to stand on their heads and think up every reason for why this is something OTHER than the software changing, but...it's the software changing.

 

 

[Rolig Loon]

In that case, this isn't a LSL scripting issue, so it really belongs in the Second Life Server forum.  :smileywink:

[Qie Niangao]

---

Prokofy Neva wrote:

No. They are not in the "sim trash" (0.0.0).

They are not underground.

They aren't anywhere.

They're gone.

You can't get the menu "get top scripts" on *MAINLAND* sims, only the Lindens could do that, so eventually one could put in a ticket but the issue is not where they went; the issue is that they disappear because of the Lindens' software.

I realize that's a shocking concept, but I think all indications are that it's not about the script in the object or some other factor but the Lindens' software.

I can't emphasize it enough: if something worked for weeks on end on the Le Tigre channel with the previous software version, then...it doesn't have an error-handling routine gone awry. Because, you know, it's working.

Sims can have lag and issues after restart and blah blah blah, but if the item WORKS for weeks on end, and there isn't issues where it sometimes disappears due to lag or whatnot, then, you have to look elsewhere for the problem.

The fault, dear Brutus, is not in ourselves, for we are underlings, but in our stars...

If it DOES NOT disappear for weeks on end UNTIL the software changes then -- gasp -- it must be the software.

I realize many people want to stand on their heads and think up every reason for why this is something OTHER than the software changing, but...it's the software changing. 

---

The software changed on Le Tigre (16.09.14.319788) where the teleporter is working, not on the main server channel, which is running the previous software version (16.08.31.319299).

To see if there were sim restarts unrelated to updates, I checked*  and Carlisle was restarted about 12 days ago now. Alston about 4, which corresponds to the past-scheduled restart days for main and RC channels (September 13th and 21st) respectively.

Presumably something changed on this particular main server release sim if the teleporter worked there before but doesn't now.

Not seeing inside the script, the bug may well be deleting the teleporter altogether, as reported, rather than hiding it in some unexpected place. Just for completeness: on Mainland, without benefit of Top Scripts, we nonetheless can get a view of everything we own in a sim (and some other stuff) with Build / Pathfinding / Linksets, as Innula mentioned.

 

---

*using llGetEnv("region_start_time")

[Innula Zenovka]

Whatever is causing the problem, I don't think it's llSetRegionPos.     

I've just tested this sample script in LeTigre Sandbox 3 (need to join the LL-owned SL Beta group for access) and on Sandbox Colborne, which is running Second Life Server 16.08.31.319299, and it works as expected in both places, except that it's a bit slow to unsit me on Sandbox Colborne (which could be caused by a number of things).  

Obviously I don't know what the script of the Fnordian teleporter looks like, but this is the basic mechanism for a llSetRegionPos teleporter, which I used in both sandboxes:

vector vHomePos;vector vTargetPos;default{	state_entry()	{		llSitTarget(<0.0,0.0,0.25>,ZERO_ROTATION);	}	changed(integer change)	{		if(change & CHANGED_LINK){			if(llAvatarOnSitTarget()){//someone sat on me				vHomePos = llGetPos();//record start position				llOwnerSay("Start pos is "+(string)llGetPos());				vTargetPos = vHomePos + <50.0,50.0,0.0>*llGetRot();//50 metres on my positive x and y axes				if(llSetRegionPos(vTargetPos)){//if I successfully moved there					llSleep(0.25);					llUnSit(llAvatarOnSitTarget());//unsit the avatar sitting on me				}			}//end llAvatarOnSitTarget			else { //avatar no longer seated				if(llSetRegionPos(vHomePos)){//got home safely					llOwnerSay("Made it home");				}				else{					llOwnerSay("Something has gone wrong.  I'm at "+(string)llGetPos());				}			}		}	}}

While I know that LL server updates do sometimes break things, I'm pretty sure that if they broke so widely-used a function as llSetRegionPos to the extent it was deleting content without trace, there would have been a massive outcry and an emergency roll-back before now.    I also suspect the makers of your teleporter would have  soon learned of the problem.

Quite possibly the server update is somehow ultimately responsible for whatever's happening,  but it doesn't seem to have broken llSetRegionPos.    

I'd forgotten that Top Scripts doesn't work on the Mainland.  Sorry about  that.    However, as Qie says, though, my other suggestion -- Build>Pathfinding>Linksets -- should show you items you own on the region. It does on Le Tigre Sandbox 3, anyway.