Sim-Crossing: a description of the current situation

[WolfBaginski Bearsfoot]

As of today, 20th September 2012, sim crossing appears to be tolerable.

A test flight with the new THI Avro Lancaster was made, totalling 20.15 km in distance which requires at least 80 transfers from one region to the next. Average speed was 15 m/s, at altutudes generally in excess of 500m. No sim crossing failed, though most showed noticeable rubber-banding.

The flight started at about 23:50 SLT on the 19th and continued until about 00:15 on the 20th.

In that time there were three problematic events:

 

At about 00:06 I was ejected from a parcel without warning by some sort of Land Security Orb. There was no warning message, and no data logged which identified identified the controller or the Orb or the location of the land protected. There was no obviously visible skybox.

At about 00:11 and at about 00:16 the aircraft was de-rezzed and returned to me with a "Parcel Full" message. It is my understanding that this is a known, and very old, bug. Is it worth wasting anyone's time with a JIRA report?

On the whole, I can live with this sort of performance. Road vehicles are not so good, with less reliable control and rubber-band events mid-region. I suppose this is a conequence of their dependence on collisions with the ground/Navmesh.

There is room for improvement, but this is hugely better than what I saw between the start of Pathfinding testing and the fixing of the Bandwidth bug. Is there a list of known problems? I know that banlines at a region edge are not visible from the neighbouring region, but what else?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Qie Niangao]

Hey, Wolf, I'm seeing something very strange with crossings on Mainland, closely related to an old bug, but I can repeat it reliably at the moment, on several locations, and think I know what's going on. I'll probably be opening a new bug report with the extra information, but while I'm investigating: Is this Avro Lancaster a pure physical vehicle? That is, it doesn't go NPV to do sim crossings, does it?  (The problem I'm seeing seems to depend on being a physical vehicle while crossing.)

[Crim Mip]

The 'parcel full' de-rez is pretty self explanitory. There weren't enough free prims in that parcel to allow the number of physical prims in your vehicle to rez. There is nothing you can really do about that and there's no requirement for parcel owners to leave any prims free for pilots. Some aircraft have a 'safefly' function that will turn them non-physical which will stop that issue from de-rezzing the plane if it's on at the time.

[Qie Niangao]

No. Except during sim crossing, a vehicle (anything sat upon, actually) can merrily cross over completely full parcels because such objects draw from a special pool of reserved prim count, over and above the 15,000 normal prims allotted to the sim. This is borked at sim crossing only, as reported in one of the oldest jiras in Second Life.

Setting stuff non-physical wouldn't matter. There is, however, a kludgy trick that (usually) prevents the parcel full problem by trying to set the vehicle PRIM_TEMP_ON_REZ during the crossing, which works (when it does) because temporary prims are also drawn from a special pool. (They're capped per parcel, but with an absurdly generous limit.)

[Qie Niangao]

I filed a bug report on that "very strange" crossings behavior I've been seeing, with a bunch of specific, repeatable examples. It was closed as a duplicate -- of a jira that I was already watching, duh! (I didn't find it when I searched because I got different warning messages -- slightly different manifestations of the same problem.)

[WolfBaginski Bearsfoot]

I am not allowed to see your Bug report, only the older JIRA, but I would, were I trying to fix this, want to know whether the big change to Physics has affected things.

[Qie Niangao]

I'm not sure which big change to Physics you mean, but Kitto reported his jira back in June. I haven't been testing this particular thing until the day posted here, so it may have started then, too.

I suspect, however, that it's actually much older... perhaps just incidentally more apparent now. If it's what it seems to be, it could screw up vehicle border crossings, regardless of physics version.

[Helma Beerbaum]

Simcrossing is a pain in the butt since the last two months. Never had problems. Not in 6 years of SL. But now i cant use my boats (sailing and motor) in a proper way. Worst thing is the camera angle changing problem.

 

LL, please do something quick!