Category: SL Tech

2026 week #29: SUG Leviathan Hour

Posted on by Inara Pey
The Simulator User Group meeting place at Longfellow

The following notes were taken from the Tuesday, July 14th, 2026 Simulator User Group (SUG) off-week meeting (the “SUG Leviathan Hour”). These notes form a summary of the items discussed, and are not intended to be a full transcript. They were taken from my chat log of the meeting, and Pantera’s video is embedded at the end of this article – my thanks to her, as always, for recording and providing it.

Meeting Overview

  • The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas is held every other Tuesday at 12:00 noon, SLT (holidays, etc., allowing), per the Second Life Public Calendar.
  • The “SUG Leviathan Hour” meetings are held on the Tuesdays which do not have a formal SUG meeting, and are chaired by Leviathan Linden. They are more brainstorming / general discussion sessions.
  • Meetings are held in text in-world, at this location.

Simulator Update

  • As recorded in my notes from the the previous Simulator User Group, there has been a bug which has been causing some regions to fail to grant capabilities.
  • Rider Linden has been investigating the issue, and a hot fix should have been / will be deployed during the July 14th SLS Main channel restarts and the restarts of the RC channels on July 15th.

Game_Control

  • Whilst not directly linked to Lua, Leviathan hopes to get his work on game_control complete and into the Lua editor viewer so it can be shipped with the Linux viewer support.
  • It has been suggested that PromptFont could be used for the game_control preferences UI, and Leviathan is investigating this.
  • He will also be providing some viewer-side actions that can be mapped to, and triggered by, pressing buttons on the game controller (e.g. fly, run, toggle Voice on/off) in addition to the existing ability to move the avatar around (walk, crouch-walk, jump, strafe).
  • Another area of work he is investigating is to add a limited interaction capability so avatars can walk up to in-world, unseated object and transmit an action event to it (such as display any dialogue menu it has associated with it).
  • Leviathan has previously mentioned the idea of adding “semantic” meanings to the game-control data, and had been considering adding a new event to provide that info.
    • However, Monty Linden has suggested using a new function call (e.g. “llGetSemanticGameControl()” or similar) which could be used in the regular event to get the same data but resorted according to how the viewer has mapped it.
  • Leviathan noted he also needs to add new data to the GameControlInput message.
  • These updates led to a further discussion on possibilities for game_control together with possible additional avatar movement option – please refer to the video for more.
  • Alongside of game_control, Leviathan has been working on enhancement for the viewer’s flycam capabilities (e.g. for use with a 3D mouse system), such as Roll. More work is required on this, which might see the enhancements ported to game-control.

In Brief

  • Leviathan noted he has been working on a fix for an issue he actually caused, in which attachment scripts sometimes cease working correctly according to parcel permissions. He tracked this to his changes in making the simulator process idle scripts faster.
  • Lua:
    • Following an internal meeting, it appears there is a “hopeful tentative plan” to release Lua in the “O” simulator update.
    • If time frames stand, this could be sometime in late August or September, given that the next simulator release will be Mango, which will be followed by Nectarine, which is targeting late July or August.
    • This would see the Lua editor viewer (with resumed official support for Linux) released around the same time, if not a little earlier.
  • Work on this has not as yet been merged into the simulator development code.
    • Leviathan believes the work is almost done, he just needs consensus for the rest of the team that the fix as he’s implemented it is the right thing to do.
    • Once consensus has been reached, the fix will likely be merged into the simulator development code for a future release.
  • It has been reported that there is an issue with events being dropped causing scripts to stop working as intended.
    • One report is that  scripted object stop working correctly when they change owner change owner, or message_linked or linksetdataRead randomly stop working.
    • The issue of scripts dropping is known to LL and Monty Linden is apparently investigating it.
  • A report has been made about the new dual-queue UDP messages processing code (currently in viewer-development but not released) in the viewer in that it causes out-of-order messages processing.
    • In particular, the first ObjectUpdate message creating an avatar can be processed too late and after the AvatarAppearance message to rez that avatar: since the avatar object is not yet created (not in object list), the AvatarAppearance is ignored and the avatar does not rez.
    • This may be due to there being assumptions in the dual queue design (both server and viewer side), which could be inappropriate, on the order in which some messages must be sent and processed for things to work properly.
    • Leviathan has indicated this will be looked into.
  • The above prompted Leviathan to note that he has a follow-up project to his UDP work and related to viewer networking he still hopes to get to.
    • This will be to tighten up the back-pressure info from viewer to server when it starts to get overloaded by network traffic, the problem being that when the viewer gets into this state, it will inform the server, but the process to send the messages takes too long and the viewer might only inform the primary simulator to which it is connected, not all the simulators it is currently talking to.
    • This led to a brief discussion on bandwidth throttling and use of an ACK UDP message to inform the server that its UDP queue is getting full, reducing the volume of messages until the flag is cleared by the viewer.
    • This was seen by Leviathan as a good idea.
    • See the last 15 minutes for the video for more on this.

Date of Next Meetings

  • Formal SUG meeting: Tuesday, July 21, 2026.
  • Leviathan Linden: Tuesday, July 28, 2026.

2026 SL viewer release summaries week #28

Posted on by Inara Pey
Logos representative only and should not be seen as an endorsement / preference / recommendation

Updates from the week through to Sunday, July 12th, 2026

This summary is generally 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.
  • Outside of the Official viewer, and as a rule, alpha / beta / nightly or release candidate viewer builds are not included; although on occasions, exceptions might be made.

Official LL Viewers

  • Default viewer  – 26.2.0.25386466510, May 19 -“flat” UI and font update – No change.
  • Second Life Lua Editor Alpha viewer 6.1.0.23768336784, April 29 – No change.

LL Viewer Resources

Third-party Viewers

V7-style

  • Kirstens Viewer S24(8) Build 3500  (Hradr) – July 11 – release notes.

V1-style

  • Cool VL viewer Stable: 1.32.4.36; Experimental 1.32.5.6 July 1 – release notes.

Mobile / Other Clients

  • Second Life Mobile 259026, July 11 (iOS and Android) – bug fixes; improved camera positioning; notification and Bubble Chat updates.

Additional TPV Resources

Related Links

2026 week #28: SL Open Source meeting: OpenGL

Posted on by Inara Pey
Hippotropolis Theatre: home of the OSD/TPVD meeting
The following notes were taken from:

  • My chat log of the Open-Source Developer (OSD) meeting held on Friday, July 10th, 2026, together with my chat log of that meeting.
  • Pantera’s video of the meeting (embedded at the end of this article) – my thanks to her for providing it.
Table of Contents

Meeting Purpose

  • The OSD meeting is a combining of the former Third Party Viewer Developer meeting and the Open Source Development meeting. It is open discussion of Second Life development, including but not limited to open source contributions, third-party viewer development and policy, and current open source programs.
    • This meeting is generally held twice a month on a Friday, at 13:00 SLT at the Hippotropolis Theatre and is generally text chat only.
  • Dates and times of meetings are recorded in the SL Public Calendar.

Official Viewer Status

  • Default viewer: Flat UI – 26.2.0.25386466510,  -“flat” UI and font update, dated May.
  • Second Life Project Viewers – Lua Editor Alpha viewer 6.1.0.23768336784, April 29.

Viewer Notes

  • 26.3 is back in development with some additional texture streaming work added. It’s currently awaiting QA testing.
  • The Lua viewer (with Linux support) still looks set to be the viewer to proceed to release status after 26.3.
  • The Graphics Care Package (GCP) viewer should be getting some attention “soon”.
    • Geenz Linden indicated that he’d to try and get more PBR fixes into GCP, and encouraged anyone with a broken environment to send details his way (+ landmarks to places that are broken vs. non-PBR).
    • The fixes for water (reflections, etc.), are “mostly there” in GCP, but there are still several edge cases that need tracking down.
    • The alpha-gamma work still doesn’t yet have a home in a viewer .

More on Updating from OpenGL

So, as everyone knows we’ve been on OpenGL for a very long time. And we’ve kicked the can on this for a while – mostly because although things aren’t moving most of the time in OpenGL land, it’s not really – moving. However, deprecation is still landing in various ways across various drivers and the like whether we like it or not, and we’re forever stuck on GL 4.1 because thanks Apple. That limits our options as far as further optimisations. But we can’t just up and move everything over night. There’s a good bit of tech debt that needs clean-up, API calls that are using a lot of older ways to do things, etc., and things that just don’t really make sense even in a “modern” OpenGL context.

– Geenz Linden, discussing plans for “after OpenGL”

  • Geenz went on to note:
    • The “first big chunk” of work – already underway and will hopefully ship with the Graphic Care Package (GCP) viewer – is cleaning up a lot of how OpenGL is used. There are still a lot of “exposed” OpenGL calls. A separate fork of the viewer cleans this up, and should be landing in GCP in the near future.
    • There needs to be work to update and modernise a lot of elements of the viewer that assume a surprising amount of old fixed function pipeline-style GL usage. This is also being worked on, and the hope is it will land in the GCP viewer.
    • There then needs to be some significant work on LLPipeline separation.
      • At its core, this means getting the rendering engine into its own library and making it so the viewer can more directly function in a headless state.
      • Whilst the viewer has had a headless mode for a while, it’ is currently under utilised, and more-or-less banks on LLRender being compiled with some flags that disable OpenGL.
      • The new library-based approach would make it so the rendering pipe is entirely its own library and optional; it just won’t have any render output on its own (it will require a render interface).
  • The current thinking at the Lab is to build a new renderer interface to replace LLRender, which can then be used to:
    • Either port the current rendering engine to Vulkan through, maybe something like an LLPipelineVulkan/ LLPipelineMetal/LLPipelineD3D12(?) + something called LLGPUDriver (which is pretty much where OpenGL/Vulkan/Metal lives).
    • Or TPVs can port in some other third party rendering engine without any coupling with LLRender.
    • Thus, the point of the renderer interface is to further decouple the viewer from the concept of rendering in the first place. Basically, there’ll like be LLRenderEngine which is probably going to be a (mostly) pure interface that LLPipeline gets to be the first consumer of.
    • He noted that this second option is still going through internal decision-making processes, and that both it and the first option are very much “a bit of a large lift”.
  • The reasons for this approach is about having an offramp from the OpenGL pipe without being super disruptive (as might be the case if the new pipeline ships prematurely, forcing people onto it similarly prematurely in a similar manner to PBR). So what is likely is that:
    • There will be an OpenGL pipeline that lingers for a while (aka “years”) as the legacy renderer.
    • Whatever lands as the “new” renderer (whether that’s a direct port to Vulkan or something else)
    • A debug setting to select which one is to be used.
  • A lot of what happens vis OpenGL overall is going depend on overall confidence in a new pipeline reaching a maturity across across a broad enough range of machines used to access SL so as to consider retiring OpenGL.
    • As such, the main thing LL will be tracking once  a project is initiated, is how well adoption is holding up on the low-end for this thing by the way. Some of those machines might be stuck on OpenGL forever, and might not get all of the shiny Vulkan stuff eventually.
  • Geenz further indicated at:
    • He’s been working on a rendering engine of his own for some time, and that is a potential option.
    • Using slang-rhi is very much an option asl well, so multiple APIs can be targeted APIs at once, and then just tweak depending on what is required to support a specific platform.
  • In terms of the up-front clean-up, etc., mentioned in Geenz’s opening statement on the subject, this was noted as being not that far away.
  • A request was made for the new renderer to support more than one pipe at a time with different camera angles, so that a single account could make use of them for shooting machinima, etc.
    • Geenz noted that this is unlikely to be officially supported.

Other Items

  • Some discussion circled the topic of “SLMesh2” (see my week #27 CCUG Summary), with Geenz noting:
    • His work on the project is liable to be more high-level, with Product Engine developers doing the coding work.
    • It will be an iterative project, with the first major element being more getting off of the current SLMesh format.
  • An update on the status of work in porting RLVa to the official viewer was requested. This was a project started a few years ago and then appeared to be moved to the sidings. No response was given, possibly because the question was missed in the OpenGL / renderer discussions.
  • A discussion on water and reflections towards the end of the meeting.

Next Meeting

2026 week #28: SUG meeting summary

Posted on by Inara Pey
The Simulator User Group meeting place at Longfellow

The following notes were taken from the Tuesday, July 7, 2026 Simulator User Group (SUG) meeting. These notes form a summary of the items discussed, and are not intended to be a full transcript. They were taken from the video recording by Pantera, embedded at the end of this summary – my thanks to Pantera for providing it.

Meeting Overview

  • The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas is held every other Tuesday at 12:00 noon, SLT (holidays, etc., allowing), per the Second Life Public Calendar.
  • The “SUG Leviathan Hour” meetings are held on the Tuesdays which do not have a formal SUG meeting, and are chaired by Leviathan Linden. They are more brainstorming / general discussion sessions.
  • Meetings are held in text in-world, at this location.

Simulator Deployments

  • No deployments for the week, just restarts
  • The next simulator update will be called Mango.

In Brief

  • Rider Linden:
    • Has merged in the rulebuilder code for Lua, so that’s ready to go. He noted that if any one wants to volunteer to fill out the tables for some functions it would be much appreciated.
    • This week he is on-call and hopes to hunt down an issue that’s causing some regions to fail to grant capabilities. He has ideas on the cause, and so is hopeful he can fix it.
    • Is also working on object publishing (prims as virtual filesystem that can be interacted with directly from VSCode, so it is possible to access and create scripts and notecards in a prim directly from VSCode rather than to have to keep switching focus between prims in world).
  • Leviathan Linden:
    • Is back working on game_control, currently doing an overhaul of the preferences UI and how the settings get formatted.
    • Notes the goal is to make it possible to map buttons to avatar movement actions (i.e. DPAD buttons to MOVE_FWD and MOVE_BACK)
    • Currently, the game_control viewer code is distinct from the Lua viewer code, but Leviathan plans on using that viewer in code merges with the game_control code.
  • Roxie Linden noted that:
    • Has been working on the WebRTC p2p IM bug where sessions fail to start, and is making progress. The issue seems to be a race condition in the back-end chat handling code; however, given the exact cause is hard to reproduce, there is no guarantee the fix in progress will correct all instances of session start failure, but Roxie optimistic.
    • On the viewer-side, has been working on changes to pull in a more recent libwebrtc + reduce some audio hiss.
  • Harold Linden (LUA):
    •  Has been busy with personal matters, but is now hoping to get back on top of  Lua PRs and resuming work on bringing the SL Lua back in-line with Luau upstream. This is seen as important as many things added to Luau upstream which would be useful for the Lua project (e.g. 64-bit integers and classes).
    • Commenting on the general state of the project, Harold added:
[the work is] Mainly polish at this point. I’d like our integer implementation to be based on Luau’s even if it’s not entirely the same under the hood so LSL can perform well, and I’d to have all scripts share a GC so that we don’t have separate memory allocators for each and every script as we do currently.
  • Monty Linden noted that lsl-definitions have been updated recently but not baked into a release and cycled around yet – this will happen “soonish”.

General Discussion

Please refer to the video below for  more on the following.

  • One of the issues with Lua on the simulator side has been the simulator crash rates. Rider described these as now being “encouraging”, many of the issues are “known and on the list to address”.
  • Harold’s comments on adopting upstream updates from Luau led to a discussion on 64-bit and 32-bit Lua support.
  • This in turn led to a discussion on Lua and llhttp.request.
  • A discussion on documentation.

Date of Next Meetings

  • Leviathan Linden: Tuesday, July 14, 2026.
  • Formal SUG meeting: Tuesday, July 21, 2026.

2026 SL viewer release summaries week #27

Posted on by Inara Pey
Logos representative only and should not be seen as an endorsement / preference / recommendation

Updates from the week through to Sunday, July 5th, 2026

This summary is generally 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.
  • Outside of the Official viewer, and as a rule, alpha / beta / nightly or release candidate viewer builds are not included; although on occasions, exceptions might be made.

Official LL Viewers

  • Default viewer  – 26.2.0.25386466510, May 19 -“flat” UI and font update – No change.
  • Second Life Lua Editor Alpha viewer 6.1.0.23768336784, April 29 – No change.

LL Viewer Resources

Third-party Viewers

V7-style

  • No updates.

V1-style

  • Cool VL viewer Stable: 1.32.4.35; Experimental 1.32.5.5 July 4 – release notes.

Mobile / Other Clients

  • No updates.

Additional TPV Resources

Related Links

2026 week #27: SL CCUG meeting summary: “updating SL Mesh”

Posted on by Inara Pey
Hippotropolis Campsite: venue for CCUG meetings
The following notes were taken from:

  • My chat log and audio recording  of the Content Creation User Group (CCUG) meeting of Thursday, July 2nd, 2026.
  • Please note that this is not a full transcript of the meeting but a summary of key topics.
Table of Contents

Meeting Purpose

  • The CCUG meeting is for discussion of work related to content creation in Second Life, including current and upcoming LL projects, and encompasses requests or comments from the community, together with related viewer development work.
    • This meeting is generally held on alternate Thursdays at Hippotropolis and is held in a mix of Voice and text chat.
  • Dates and times of meetings are recorded in the SL Public Calendar.

Official Viewer Status

Viewer Notes

  • Viewer 26.3.0 is undergoing some fine tuning as it passes through QA, and the hope is this work will complete in the next week or two, allowing it to surface as a beta / RC viewer.
  • The Lua editor viewer should be next in line to progress towards release behind 26.3.
  • The Graphics Care Package (GCP – including Index of Refraction, PBR specular, significantly improved Screen Space Reflections, HDR EEP settings, etc.) viewer is liable to be some time after the Lua viewer.
    • A request was made for displacement maps, but these were referenced as being unlikely any time soon.

Discussion: “Updating SL Mesh”

As introduced by Geenz Linden:

Today I had a topic I’d like people to consider and see what people want here. If we were to do an update to SL Mesh, what would people like? Our current setup is quite old, and we’d need to adopt a new format internally to really push things forward with newer features and such. So today it’s not easy to extend due to viewer compatibility issues. But if we were to revisit this, say having a variant of glTF, that enables extensibility much more easily – what sort of features would people be interested in seeing?

– Geenz Linden

This obviously caused a wide range of feedback with comments including:

  • Increasing the number of available materials faces.
  • glTF mesh hierarchies with proper origins.
  • Implementing Universal Scene Description support.
    • This was seen as “interesting” and that adding SL-specific schema would be “easy”.
  • Allowing partial editing of glTF metadata via the viewer’s Build floater and scripts to allow building more complex scenes with multiple meshes, object hierarchies etc.
  • Basic in-world mesh building tools such as mesh panels, the ability to edit vertices (which would require care!) and / or manipulate vertices and faces.
    • Seen as difficult to implement due to the mechanics of assets in SL.
  • “Fleximesh” for clothing, hair, etc.
    • Seen as difficult to pull off, while a physbones (“physics bones”, basically a defined “chain” of bones with a beginning and end, with the viewer simulating them moving around and such. It’s a technique seen in low-cost games and has the advantage of being low-overhead for the viewer to simulate, if a little basic) approach might be preferable.
  • Better Blender support.
  • More bone control for avatars, notably custom skeletons / avatar rigs.
    • Seen as likely necessitating some sort of in-viewer set-up unless we were to adopt something like VRM and utilise something like the VRM Unity-based rig. This was seen as “not out of the question”.
    • These comments came with a warning that there are a lot of opportunities for depositing bullets in pedal extremities with custom skeletons (mainly around animation compatibility), but these could be navigated were things to move in this direction.
    • A caveat was also given that while there has been thinking about custom skeletons within LL, “It’s not s short path”.
  • The requests for custom skeletons / rigs raised a second question: how would people use them. Responses included:
    • Ropes, plants, chains, snakes, cows.
    • “Everything that needs to move for animation.”
    • Animals like birds or fish.
  • Blendshapes (see this request as well).
    • Geenz noted that some hardware acceleration added for skeletons, but further hardware acceleration would be necessary for something like blendshapes – and noted this also is not off the table.
  • Geenz further noted on the discussion:
The biggest thing that stops us from doing this is really just the whole we can’t touch the original format. It has to stay in amber. But that doesn’t mean we can’t have a new internal format.
    • Exactly how this would work would be a case of TBD – presumably if / when any project has been scoped in terms of content and goals.

Geenz’s final comment on the discussion was:

I just want to close with although these are all good suggestions, I can’t guarantee when/if these will land. Chances are if we do a SLMesh 2, you’re getting feature parity first before we move on to adding shiny stuff to it. Whatever we do here will be iterative, rather than a big all in one release.

General Discussions

  • Kyle Linden indicated a possible change in direction for documentation:
    • The Second life Creation portal (/Getting Started with Scripting) could be refocused more towards helping those new to Second Life.
    • The Second Life Wiki might be re-opened for broader edit access and maintenance of information there (some of which is now badly out-of-date).
    • No further details were forthcoming.
  • As a part of the discussion on SL Mesh, requests were made for enhancements to the prim building capabilities (e.g. adding a bevel capability, more basic prim types, etc.). It was indicated that there are currently no plans to enhance or extend the prim system at present.
  • A hint was given that in terms of graphics API, it appears that LL is leaning back towards Vulkan as a solution, with the promise of more to talk about this in the future.

Next Meeting