Category Archives: SL Tech

SL project updates week 21/1: server, viewer

Costa Blanco, Costa Blanco; Inara Pey, May 2017, on Flickr Costa Blancoblog post

Server Deployments

As always, please refer to the server deployment thread for the latest updates and news.

  • On Tuesday, May 23rd, the Main (SLS) channel was updated with the server maintenance package previously deployed to LeTigre in week #20, containing the updated server-side parcel access override settings (more below)
  • On Wednesday, May 24th, the RC channels should be updated with a new server maintenance package containing the parcel access override controls, together with a fix for BUG-100704, “[Server] If Anyone Can visit is selected after Allow Group was set only group members can enter”.

SL Viewer

The Maintenance viewer, version, dated May 18th, 2017 was promoted to release status on Tuesday, May 23rd.

This viewer is notable for its inclusion of some improvements to Trash purging behaviour, and support for the parcel access overrides which as of this week are fully deployed across the grid.

I have an overview of this viewer, which examines both the Trash purging changes and the parcel access overrides in detail, as well as touching on the other updates included in the release.

Outside of this, the current pipeline remains as:

  • Release channel cohorts (please see my notes on manually installing RC viewer versions if you wish to install any release candidate(s) yourself):
    • Voice RC viewer, version, dated May 5th
    • Project AssetHttp project viewer,  version, dated May 4th – This viewer moves fetching of several types of assets to HTTP / CDN – overview
  • Project viewers:
    • Project Alex Ivy 64-bit viewer, version, dated May 11th
    • 360-degree snapshot viewer, version, dated November 23, 2016 – ability to take 360-degree panoramic images.
  • Obsolete platform viewer version dated May 8th, 2015 – provided for users on Windows XP and OS X versions below 10.7.

Expect the two RC viewers to be updated to bring them to parity with the new release viewer viewer.

Infrastructure Updates

As noted in my week #20 updates (notably the TPV Developer meeting notes), the Lab is working on a range of infrastructure updates, together with updates to things like the teleport re-try throttle (which can place a considerable load on the “receiving” region’s simulator). It is hoped that these updates will a) help SL progress into the future, b) potentially offer further increases in the numbers of avatar regions can support.

Other Items

Changes to Mesh Upload Access

Linden Lab recently changed the requirements for being able to upload mesh content to Second Life. For more information, see my separate update.

Instancing Regions?

Note: this is not an actual project with the Lab, nor is it necessarily on the roadmap for SL development. What follows is purely in the realm of speculative discussion.

During the Simulator User Group Meeting on Tuesday, May 23rd, it was asked if instancing regions (notably private standalone regions) might some day be possible. That is, if there is a stand-alone region hosting a very popular event, a copy of the entire region might be spawned, which would then allow people into it to deal with the demand.

While there are a wide range of infrastructure, permission system  and other issues associated with it (how is the instance to be paid for? what about No Copy items, can they be reproduced in an instance of a region, where technically they aren’t a duplicate? How is the required hardware managed & what happens when demand for additional server space isn’t high?, etc.), the idea wasn’t ruled as being completely out-of-bounds. Right now it remains purely on the “someday maybe” wish list.


2017 Viewer release summaries week 20

Logos representative only and should not be seen as an endorsement / preference / recommendation

Updates for the week ending Sunday, May 21st

This summary is published every Monday, and is a list of SL viewer / client releases (official and TPV) made during the previous week. When reading it, please note:

  • It is based on my Current Viewer Releases Page, a list of all Second Life viewers and clients that are in popular use (and of which I am aware), and which are recognised as adhering to the TPV Policy. This page includes comprehensive links to download pages, blog notes, release notes, etc., as well as links to any / all reviews of specific viewers / clients made within this blog
  • By its nature, this summary presented here will always be in arrears, please refer to the Current Viewer Release Page for more up-to-date information.

Official LL Viewers

  • Current Release version:, dated April 3, promoted April 19th – formerly the Maintenance RC viewer overviewdownload page, release notes – No Change.
  • Release channel cohorts (please see my notes on manually installing RC viewer versions if you wish to install any release candidate(s) yourself):
    • Maintenance RC Viewer, version, released on May 18th – new trash purging behaviour, support for estate access overrides (download and release notes)
  • Project viewers:
    • No updates.

LL Viewer Resources

Third-party Viewers



Mobile / Other Clients

  • No updates.

Additional TPV Resources

Related Links

SL project updates 20/3: TPV Developer meeting

Nitroglobus Roof Gallery: Black and White Women – blog post

The majority of the notes in this update are taken from the TPV Developer meeting held on Friday, May 19th, 2017. The video of that meeting is embedded at the end of this update, my thanks as always to North for recording and providing it. Timestamps in the text below will open the video in a separate window at the relevant point for those wishing to listen to the discussions.

Server Deployments Re-cap

  • There was no Main (SLS) channel deployment or restart on Tuesday, May 16th.
  • On Wednesday, May 17th, the three RC channels were updated as follows:

SL Viewer

[1:00] The Voice RC viewer has an elevated crash rate, and the Lab currently haven’t determined why.

The Maintenance RC viewer updated to version on Thursday, May 18th. This viewer currently has a lower crash rate that the other RC viewers (although it has not been out that long), so might be a candidate for promotion. I have an overview of this viewer for those interested.

64-bit Viewer

[2:23] The last major functional addition for the 64-bit Alex Ivy viewer is currently with the Lab’s QA. If all goes well, a further project viewer update should arrive in week #21 (commencing Monday, 22nd May).

This introduces a new executable to the viewer – SL Launcher – which runs an update check at start-up. If there is a new version of the viewer available, the Launcher manages the download and installation – including ensuring Windows users get the right version for their operating system (32-, or 64-bit).  If there is no new version to install, or once the viewer installation has completed, the Launcher will launch the viewer as a child process, and will shut down when the viewer exits at the end of a session.

The plan is to move the crash data capture package to the Launcher in the future, which will give full end-to-end monitoring of the viewer in the event of a crash.

360 Snapshot Viewer

[6:07] The work on the 360 snapshot viewer is once again progressing. A new library has been added, which provides the appropriate meta data so that websites supporting 360-degree viewing can correctly such images taken by the viewer on upload, eliminating the need to process them separately via the web service currently supplied by the Lab.

This work is currently being tested, and should find its way into a project viewer update some time in the next two weeks or so, with a release candidate hopefully not too far behind that.

Region Crossing Hand-off / Caps Router Issues

[7:43] Fantasy Faire experienced very high levels of region crossing hand off problems with avatars trying to move between the various regions. A similar issue has surfaced at the just-opened Home and Garden Expo.

While it issue isn’t new, the Lab found a cause is the Caps Router running out of connections due to the number of avatars it is attempting to serve. New monitoring has been put in place which will determine how many connections the Caps Router is using, and when it is approaching its limits. The data gathered will be used to help better determine how many connections are needed, allowing the Lab to adjust the number supported.

This work is going to be carried out incrementally, starting with an initial RC deployment in week #21 containing conservative adjustments in the hope of avoiding creating additional bottlenecks in changing things too radically at one time. However, the hope is that the changes will in time result in two improvements:

  • It could result in an increase in the number of avatars a region can comfortably support
  • As this is an issue at the SERVER level (not the simulator), the changes should help reduce people on regions with few avatars on them experiencing issues as a result of the region being hosted on the same server as one (or more) regions with a lot of avatars on them.

As a result of understanding the problem, the Lab was aware the issue was impacting the Home and Garden Expo even before it had been reported.

Unsuccessful Teleports Impacting Region Performance

[14:20] During investigations into the region issues at Fantasy Faire, the Lab noted that a simulator running a busy region has to carry out a lot of work to determine whether or not someone can teleport into it, which can degrade overall simulator performance.

To combat this, the Lab is going to change the teleport re-try throttle following a failed TP. As viewer-initiated teleports are already somewhat throttled, the change should not affect them. However, it will likely mean that the very rapid retry TP HUDs (aka “TP hammers”) will break or degrade in their performance unless adjusted.

The hope is that by reducing the load placed on a simulator as it tries to deal with too rapid a succession of TP requests which cannot be granted as the region is full, overall performance will be improved and those already in the region will enjoy a better experience.

This change should be appearing in a server RC update soon.

Additional comments on teleport failures:

  • A queuing system will not be added, as this is deemed to be too difficult to implement and manage.
  • There is no relationship between the size of an avatar’s inventory and the frequency with which that avatar may experience teleport failures. However, the amount of items attached to an avatar, the scripts they are running, etc.
  • The Lab can monitor teleport failures in real-time.

Automatic Additional Logging after Region Crashes

[29:27] It was asked if additional logging could be automatically enabled on a region crash. This is something that cannot be done, and Oz’s belief is that doing so would result in an additional load on the simulator during recovery, and so not be a good idea.

Avatar and Object Rendering Cost Investigations

[31:00] The Lab is continuing work in reviewing the rendering cost calculations for in-world objects and avatars, work I first reported on in September 2016. However, the numbers aren’t at a point where any adjustments can be made to the calculations.

Fun Fact

Oz Linden marked his seventh anniversary at the Lab this week – so a belated happy rezday to him! Some of us can likely remember his 2010 appearance at the SLCC, when Esbee Linden introduced him to the audience in Boston 🙂 .

Oz at one of the viewer / open-source panels at SLCC 2010, with Esbee Linden just visible to the right





SL project updates week 20/2: Content Creation User Group w/audio

The Content Creation User Group meeting, at the Hippotropolis Camp Fire Circle (stock)

The following notes are taken from the Content Creation User Group meeting, held on  Thursday, May 18th, 2017 at 1:00pm SLT at the the Hippotropolis Camp Fire Circle. The meeting is chaired by Vir Linden, and agenda notes, etc, are available on the Content Creation User Group wiki page.

Audio extracts are provided within the text, covering the core points of the meeting. Please note, however, that comments are not necessarily presented in the chronological order in which they were discussed in the meeting. Instead, I have tried to place a number of related comments by Vir on specific topics into single audio extracts and with their associated notes, in the hope of making those topics easier to follow, and without changing the context of the comments themselves.  If you would prefer to listen to the discussion and comments in the order the meeting unfolded, I have embedded a video recorded at the meeting by Medhue Simoni. My thanks to him making it available.

Supplemental Animations

While this is now an adopted project, the focus has been on animated objects, and so there is no significant progress on this work at present.

Applying Baked Textures to Mesh Avatars

No movement on this.

Animated Objects

Vir has spent most of the week since the last meeting working on animated objects and developing prototypes and looking at proof-of-concept to see how objects might be animated using the avatar skeleton. He describes the results thus far as encouraging whilst also pointing out it is still early days with the work, so it is still far too early to determine what the final architecture will be.

The viewer already has a notion of an avatar without a human operator, which is notably seen when uploading an avatar mesh or animation. This notional avatar isn’t rendered graphically, but is oriented using transforms so that an object can use it as a source of joint motions. This is not necessarily how things will work with any finished product, but it is enough to demonstrate what might be possible.

Currently, Vir is working with single object rigged meshes, and would be happy to receive similar models, preferably with associated animation, if people have anything they believe would be useful for helping with these tests.

It is hoped that “being animated” will be an additional property which does not require a new mesh upload option, so that any rigged mesh for which you have Edit permissions for can be set to use the property  so that it can be driven by its own animations.  Currently:

  • This will likely mean the object will no longer be attachable to an avatar
  • It has yet to be determined if this property will be a new prim type or an additional field added to an existing object, etc
  • It will not require any changes to the current mesh uploader; the property to convert a mesh to an animated object can be set post upload.

A suggestion was made that the animated mesh should use its own skeleton when independently rezzed in-world, but a sub-set of a controlling avatar’s skeleton if it is attached. This would allow things like animated horses to be rezzed in-world and then sat on for riding or pets to be “picked up” and carried,  as is currently the case with some scripted animals already.

The testing carried out thus far hasn’t looked at animated attachments, although Vir appreciates the potential in having them. However, there are concerns over potential additional performance impacts, the risk of bone conflicts (what happens if your avatar is already using one or more bones some something and these same bones are used by an animated attachment).

While not ruling the potential out, Vir’s tests so far haven’t encompassed animated attachments to determine what issue might arise.  There are also other factors involved in avatar control which need to be looked at with animated objects: hover height, offsets, position, etc., all of which might affect how an animated object might be seen / behave.

Scripting / LSL Commands

The current work has not so far looked at LSL commands or command sets for the new capability. However the intent remains that scripts for controlling an animated object will be held within the inventory for that object, and able to call animations for the object also contained within the object’s inventory, so things are not straying too far from what can already be doing vis scripted control of in-world objects.

Performance Impact

Similarly, it is hard at this point to know what the likely performance hit might be. Bento has shown that adding more bones to the avatar skeleton doesn’t create a notable performance hit, so providing a skeleton for in-world objects shouldn’t cause any greater impact than a basic avatar. However, associating a rigged mesh object with than skeleton, then animating the joints, etc., will have an impact, particularly if a lot of animated objects are used in any given place.

This is something that will be looked at in greater detail once there is a project viewer available for testing alongside any server-side updates, although the Lab doesn’t intend to make it easy for a region to be spammed with multiple versions of an animated object, and this may in part be linked to the Land Impact associated with such objects.

Attachment Points on Animated Objects and Linksets with Animated Objects

While attachment points are also joints within the skeleton being used by an animated object, and so can be animated, they would not actually support having other objects attached to them, as the animated object doesn’t have links to other objects in the way an avatar does.

An animated objects could be a linkset of rigged meshes which are identified as a single object, with all of the rigged meshes referencing the same skeleton. Things might be more difficult if static mesh objects form a part of the object, as it is not clear how the positioning of these would be controlled, and more testing is required along these lines.

Body Shapes and Animation Scaling

Requests were made to allow animated objects to have body shapes (which would allow slider support, etc.), and  / or animation scaling.

Because of the changes that would be involved in both, coupled with the potential for conflicts in the case of animation scaling, Vir does not see either as being part of this work – as previously noted, assigning a body shape to an animated object would impact a number of other back-end systems (such as the baking service), adding significant overheads to the project.

As such, the Lab would rather keep the work focused, building on something that could be rolled-out relatively quickly, and then iterated upon. However, one option that might be considered is having some kind of root node scale, based on the scale of the animated object that would size the skeleton to the scale of the object, rather than vice versa, possibly by altering how the mPelvis bone is managed for such objects.

[56:37-1:02:30] The final part of the meeting delved into the relative efficiency of mesh and sculpts, and matrix maths on CPUs / GPUs, and the complexities of rendering animated objects, together with a reminder that object rendering costs are currently being re-examined.

Other Items

In-World Mesh Editing?

[41:00-55:55] Maxwell Graf raises the idea of having a simple in-world mesh editor / enhancements to the editing tools which would allow creators to adjust individual face, edge or point in an object, presenting a reason for mesh creators to spend more time in-world and which might allow non-mesh builders more flexibility in what they can do as well.

The current toolset  – mesh uploader and editing tools – would not support such a move. There are also a number of potential gotchas on a technical level which would need to be understood and dealt with, and in order for the Lab to consider such a project, any proposal would have to consider the smallest subset of capabilities available in dedicated mesh creation / editing tools like Blender and Maya that would be useful to have in-world, so that it might be possible to define the overall scope of the work required in terms of resources, etc., and what the overall return might be on the effort taken.

Based on the conversation, Max is going to try to put together a feature request / proposal, even if only for the purposes of future discussion.