Category: TPVD / Open Source User Group

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Open Source User Group (OSUG) held on Friday, October 24th, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The OSUG meeting is a combining of the former Third Party Viewer Developer meeting and the Open Source Development meetings. 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.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Default viewer 2025.07 7.2.2.18475198968 – Apple Silicon Support – dated October 16 –  No Change.
  • This viewer now ships as a “Universal Binary” that contains both the Intel and Apple Silicon versions of the viewer. It should give performance gains on the Apple Silicon version in particular.
  • Also includes various WebRTC improvements and bug and crash fixes.
  • Known issues:
    • This version does not support convex decomposition for physics meshes with Apple Silicon. This will be hopefully be corrected in a future update or release, possibly with the help of a code contribution.
    • Navigation buttons in the in-viewer browser are no longer present for marketplace and search – these will be restored in a future update.
    • Apple Silicon does not support pathfinding tools.
    • Subtle rendering differences might be noticed on certain configurations and EEP environments.
  • Github Changelog.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

Viewer Updates

• 2025.07 has seen an uptick in crash rates as a result of some WebRTC changes, and LL is working to resolve this. As such, TPVs looking to ship WebRTC / updates are advised to keep an eye on the Develop branch for relevant commits to integrate into their viewers if they would prefer to avoid the 2025.07 issues.
  • As apart of the overall WebRTC project, a server-side update is anticipated as being ready for release in the next 1 to 2 weeks, with fixes for some issues and some new features.
• Viewer 2025.08 will be a maintenance update with a focus on resolving crash issues, with the hope it may also include some log-in time improvements for those with very large inventories.
• Work is progressing on a contributed Linux update, details in this Github PR, which LL is hoping to “land” this year.
• A new SLua project viewer is in the works. This should include Rider Linden’s work on an official native VSCode plugin for LSL and SLua, as noted in my more recent Simulator User Group meeting summaries.

In Brief

Please refer to the video for the following:

• A general discussion on the viewer UI and making it easier for new users to quickly discover how to mute those using Voice in order to be obnoxious / harass, without necessarily requiring guidance from a mentor / friend on how to do so.
  • The above also broadened into a more general conversation on improving the chat functionality in the viewer in general (e.g. Voice controls + the conversations floater, etc.).
  • Also touched on was the on-going work with Project Zero (viewer in a browser) to reconstruct the viewer UI (or elements thereof) with a HTML/React-style approach – although this is being done without any intent to “break” the existing UI approach within the viewer.
  • As Geenz Linden noted (and the meeting chat demonstrated), views on the viewer UI and things like the conversations / chat floaters (or CHUI – Conversation Hub User Interface, to use the terms employed when the overhaul Viewer 2 chat UI was first introduced back in 2011) tend to be highly subjective when opinions are voiced. As such the suggestion was made to use the Feedback Portal to offer feature requests on what might be done to improve text chat & its UI elements (and Voice chat), and to upvote features thought to be worthwhile.
• The second half of the meeting included a lot of general discussion on what might be done to “improve” the viewer experience in general, together with a side discussion between Geenz Linden and Henri Beauchamp on the alpha-gamma fix for legacy objects rendering by PBR + improving the appearance of water on PBR rendering.
  • A very short-form summary of these latter two items is to note server-side work is required for the alpha-gamma fix, but is currently stalled, whilst water is awaiting the updates to SSR (screen space reflections), which has yet to be prioritised for a future viewer release.

Next Meeting

• Friday, November 7th, 2025 at the Hippotropolis Theatre.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Open Source User Group (OSUG) held on Friday, September 26th, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The OSUG meeting is a combining of the former Third Party Viewer Developer meeting and the Open Source Development meetings. 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.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Default viewer 2025.06 7.2.1.17108480561 – August 29 – No Change.
  • Inventory Favourites System, plus assorted new features.
  • Improvements to avatar system; camera and movement; chat; voice; content creation tools.
  • Mesh uploader updates.
  • Text & UI polish.
  • Fixes for Environment and Rendering; stability and crashes; UI.
  • System improvements.
• Second Life Beta viewer 2025.07 7.2.2.17774206511 – Apple Silicon Support – September 26 –  NEW.
  • This viewer now ships as a “Universal Binary” that contains both the Intel and Apple Silicon versions of the viewer. It should give performance gains on the Apple Silicon version in particular.
  • Also includes various WebRTC improvements and bug and crash fixes.
  • Known issues:
    • This version does not support convex decomposition for physics meshes with Apple Silicon. This will be hopefully be corrected in a future update or release, possibly with the help of a code contribution.
    • Navigation buttons in the in-viewer browser are no longer present for marketplace and search – these will be restored in a future update.
    • Apple Silicon does not support pathfinding tools.
    • Subtle rendering differences might be noticed on certain configurations and EEP environments.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

Viewer 2025.07

• At the time of the meeting, the 2025.07 viewer was pending release.
• The first part of the meeting involved discussions on potential routes to provide convex decomposition for physics meshes for this viewer version via open-source options, on both a short-term temporary basis and long-term solution.

In Brief

Please refer to the video for the following:

• Appearance fixes: this is being considered for the 2025.08 viewer update, and Geenz has requested feedback / discussion on via Discord.
• [Video: 13:12-19:52] A request was made to change the LOD default as a part of the work to provide convex decomposition on this viewer. This was denied, the focus being on providing a “feature complete” version of the viewer for Apple Silicon.
  • However, this led to a discussion on how best to handle LODs and auto LODs.
• [Video: 20:20-End] A broad discussion on dressing avatars, including:
  • Baking clothing meshes (sort-of a-la BOM) / using mesh proxies fore clothing / layering clothing, and potential for improvement performance as a result.
  • Providing a scripted means to dress avatars according to the requirements of an Experience (e.g. if someone just a mech combat experience, scripts in the experience dress their avatar accordingly).
  • “Discouraging” overly-complex avatars.
  • This discussion encapsulated general ideas, feedback, etc., and also touched on things like VRAM use, etc.
  • The latter part of the discussion strayed into texture resolution + texture compression, licensing and libraries, etc.

Next Meeting

• Friday, October 10th, 2025 at the Hippotropolis Theatre.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Open Source User Group (OSUG) held on Friday, September 12th, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The OSUG meeting is a combining of the former Third Party Viewer Developer meeting and the Open Source Development meetings. 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.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Default viewer 2025.06 7.2.1.17108480561 – August 29 – No Change.
  • Inventory Favourites System, plus assorted new features.
  • Improvements to avatar system; camera and movement; chat; voice; content creation tools.
  • Mesh uploader updates.
  • Text & UI polish.
  • Fixes for Environment and Rendering; stability and crashes; UI.
  • System improvements.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

Viewer 2025.07

• Apple Silicon support has been merged into the 2025.07 code.
• Chrome Embedded Framework is set to be updated to the latest version of 139.
• The Mac OS version might receive the old HACD implementation for mesh uploads as a tide-over until the 2025.08 release.
• Work is in progress on viewer-side WebRTC fixes (see: [WebRTC] Rework device handling sequence so that we can handle unplugging/re-plugging devices #4593), and it is hoped these will be included 2025.07.

In Brief

Please refer to the video for the following:

• In order for PBR lighting to render anywhere close to correctly, alpha blending had to be switched from SRGB to linear colour space. This can cause some older content using Blinn-Phong, to look either more opaque or more transparent than in did pre-PBR.
  • This fix – Fix the alpha gamma value when rendering legacy diffuse textures and materials #4601 – has been subject to internal discussion at LL. It appears that Geenz is considering taking the alpha / gamma parameter from Alpha gamma parameters #2668 and apply it to #4601.Alpha / Gamma issues (linear alpha blending).
  • The plan is all BP content will default to gamma space blending to get around the problem of permissions on older content without introducing another ugly permissions hack.
• A fragmented discussion on LL possibly offering better Linux support in the future (and subject to priorities) and on Linux packaging in general, which ran through a good portion of the meeting.
• A discussion on alpha being inverted on PBR vs. Blinn-Phong  (e.g. 1 is fully transparent on BP and fully opaque on PBR), and on whether one of the values should be flipped. Geenz indicated that no flipping would occur, due to the risk of confusing for people, given the two (PBR and Blinn-Phong) are distinct workflows.
• Appearance fixes #3492 for current Outfit Folder (COF) issues is potentially being looked at for inclusion in the 2025.08 viewer update.
• CoACD is being considered (alongside other options) as a replacement for Havok mesh decomposition.
• Again, please refer to the video for the rest of the discussion.

Next Meeting

• Friday, September 26th, 2025 at the Hippotropolis Theatre.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Third-Party Developer meeting (TPVD) held on Friday, August 29th, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The TPV Developer meeting provides an opportunity for discussion about the development of, and features for, the Second Life viewer, and for Linden Lab viewer developers and third-party viewer (TPV) / open-source code contributors to discuss general viewer development. This meeting is held once a month on a Friday, at 13:00 SLT at the Hippotropolis Theatre.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Default viewer 2025.06 7.2.1.17108480561 – August 29 – NEW.
  • Inventory Favourites System, plus assorted new features.
  • Improvements to avatar system; camera and movement; chat; voice; content creation tools.
  • Mesh uploader updates.
  • Text & UI polish.
  • Fixes for Environment and Rendering; stability and crashes; UI.
  • System improvements.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

Viewer 2025.07

• Currently in development.
• Will include “proper Discord support” for those with a Discord account  – further clarification to follow as the viewer is developed; and possibly Apple Silicon support.

In Brief

• Meeting update: the TPVD and Open-Source Developer meeting will be merging. The combined meeting will be held once every two weeks, and utilise the TPVD meeting time slot and location. This merge comes into effect on Friday, September 12th, 2025.
• Code merge policy update:
  • This is intended to better align merging release branches into develop with git flow.
  • LL should now merge code in a given release branch on a fairly regular basis moving forward – so no more waiting for things to go into main before merging up into develop, and moving forward, the Develop branch should always have the latest code LL intends to release in the near future.
  • The latest release code will always be in the main branch.
  • Project branches are still TBD on how they will be handled, as there are often things that need a lot more work before they’re ready for general consumption.
• The latest version of Autobuild defaults to 64 bit, allowing viewer compilers to remove AUTOBUILD_ADDRSIZE from their build environments.
• User Joe Magarac (animats) has been working on viewer-side “infinite draw distance” using mesh / sculpt imposters for surrounding region (e.g. one region, 4 region, 16 region, 64 region, etc., – currently only terrain), with each imposter having its own UUID and an a Land Impact of 1 LI.
  • This work is in test within his own Sharpview viewer (not on general release), and will be made available to other viewers.
  • Geenz Linden has been following the work, and has an alternate view on achieving the same result (e.g. having the simulator specify a UUID message to an imposter object which any viewer can then just load and display as required, rather than having everything driven from the viewer), and has suggested the work could benefit for a more collaborative approach.
  • This resulted in a general discussion on project status, possible direction, options for imposter creation, possible issues of content protection if imposters include content information (e.g. buildings), etc, which ran through most of the meeting. Please refer to the video for details.

Next Meeting

• Friday, September 12th, 2025 at the Hippotropolis Theatre (combining with the Open-Source Developer meeting, per the above notes).

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Third-Party Developer meeting (TPVD) held on Friday, August 1st, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The TPV Developer meeting provides an opportunity for discussion about the development of, and features for, the Second Life viewer, and for Linden Lab viewer developers and third-party viewer (TPV) / open-source code contributors to discuss general viewer development. This meeting is held once a month on a Friday, at 13:00 SLT at the Hippotropolis Theatre.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Default viewer 7.1.15.15596336374 promoted June 12 – No Change.
• Second Life Project glTF Mesh Import (2025.05 Beta) 7.2.0.16356654553 July 23 – New.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

Code Contributions “Shovel List”

• Signal Linden has produced a “shovel list” of code contributions the Lab are seeking from open-source developers.
• Two high-value items identified in the list are:
  • A RFP for replacing Autobuild in the viewer build process.
  • A RFP for replacing the Havok convex hull decomposition mechanism with an open-source equivalent.
• The former RFP is as removing Autobuild as a significant barrier / burden to those trying to learn how to the build the viewer. Suggestions for preplacement include pure Cmake, or using Vcpkg or Conan for dependency management, or vendor dependencies in the repo, etc.
  • Related to this, Brad Linden has started an experimental branch simplifying LL development environment. In is not ready for general use, but the idea is that the Build Instructions in the README should “just work” and not require having Autobuild installed or set up properly ahead of time. The is part of on-going work to overhaul the viewer build process.
• The latter RFP above is part of the Lab’s aim to remove the Havok sub-library from the viewer, which also includes a means to still visualise the navmesh.
• The above sparked a short conversation on the viewer build process.

Experimental Rewards / Bounty System

• LL has launched an experiment rewards programme offering monetary rewards against certain Github issues.
• Powered by Opire, the programme is explained here.
• These rewards are not meant to replace regular open source development, but rather to drive contributions on items LL have been unable to get much traction on.

In Brief

•  LL has also open sourced the LSL definitions project, the authoritative definition of LSL library functions, types, etc. It is used to perform codegen in the server, building out the bindings for LSL and SLua, and also drives the LSL editor tooltips.
• PR Appearance fixes #3492 is still requiring attention from linden Lab, and is currently stalling the work on getting RLV into the official viewer. 
• Camera Constraints Bug (below -0 metre altitude) has been filed. This affects all v7 viewers, and is under investigation.

Next Meeting

• Friday, August 29th, 2025 at the Hippotropolis Theatre.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from my chat transcript + the video recording by Pantera (embedded at the end of this summary) of the Third-Party Developer meeting (TPVD) held on Friday, June 6th, 2025. My thanks to Pantera as always for providing it.

Meeting Purpose

• The TPV Developer meeting provides an opportunity for discussion about the development of, and features for, the Second Life viewer, and for Linden Lab viewer developers and third-party viewer (TPV) / open-source code contributors to discuss general viewer development. This meeting is held once a month on a Friday, at 13:00 SLT at the Hippotropolis Theatre.
• Dates and times are recorded in the SL Public Calendar, and they are generally conducted in text chat.
• The notes herein are a summary of topics discussed and are not intended to be a full transcript of the meeting.

Official Viewers

• Official Viewer: 2025.04 – 7.1.14.15192634334, issued May 25, promoted May 28 – NEW.
  • Chat Mentions (Early Support): Type @ then pick a name. To follow: audible alerts and highlight colour pickers.  This does not support generic mentions such as @everyone or @here.
  • My Outfits subfolders: now supports the use of subfolders.
  • Build Floater improvements: increase to scale boundaries; Physics Material Type now updates when selecting linked objects; Repeats per Meter value no longer incorrect for non-uniform sized objects.
  • Hover height: the minimum/maximum is now +/- 3 meters.
  • Snapshot floater: L$ balances can be hidden independently of the rest of the UI.
  • Preference Search bar: general usability and readability improvements.
  • Refer to the release notes for full updates and fixes.
• Second Life Project glTF Mesh Import, version 7.1.14.15361077240 June 2 – NEW.
  • This is an early Alpha release with some of the rough edges and already resolved many bugs and crashes, although more are to be found, together with general feedback from the community. Please read the release notes if you intend to test this viewer.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

glTF Mesh Uploader

• The GLTF Mesh Uploader will be the next viewer release, although it doesn’t as yet have a new-format version number.
• It is now available on the Alternate Viewers Page (and the version current at the time of writing is linked-to above).
• The initial release is regarded as a “pretty rough cut”, with fixes already streaming into the code branch such that there is likely to be an update within the week.
  • Those trying the initial release should be aware that rigged mesh import in particular is in an “iffy state” for some of the more complex avatars.
• As the next planned release, it will be merged-up to the Develop branch shortly – so if anyone would like to get some PRs in now would be a really good time to do that.

Test Items

Linden Lab is seeking content content creators who would be willing to contribute items for testing. Specifically, the Lab is seeking:

• Rigged meshes only – unrigged content is not required at this time.
• Everything from the most basic avatar mesh to complex bento, fitted, etc. meshes, clothing and Animesh is welcome.
  • However, avatars with onion layers should not be submitted. If possible, merge such avatars into a singular mesh with rigging in order to help simplify the Lab’s debugging work.
• Content should be supplied in both glTF and COLLADA.DAE formats, to allow for A/B testing.
• Content files should be sent to gltf@lindenlab.com.

glTF Uploader “Phase 2”

• A “reunification” of the various asset import flows, focused on under-the-hood work with the import pipeline.
  • It used to be that assets like sounds, animations, images, etc., were uploaded through a single API when uploaded, but since the arrival of mesh, new asset upload types have diverged from the “common” flow to use their own.
• The idea now is to provide a single API to get things from a creator’s computer and in-world to simplify the upload process.
• According the CCUG meeting, this work will include an improved preview capability, providing more representative of what creators can expect to see under a set of EEP parameters, etc.
  • The ability to preview items in-world on Agni (the main grid) prior to upload will not be provided. However, there is still Aditi (the beta grid) for this.
• It is also hoped that the import flow can be made easier to understand for existing and new content creators (e.g. providing a better preview; having things laid out in a way that makes potential problems more obvious, etc.).

In Brief

• Switching away from OpenGL: this has not been mentioned for a while, and currently, it looks like LL is going to use an existing API abstraction, so as to allow Apple Metal to be targeted as well. The API mentioned was “something based off of NVIDIA’s Slang API” – with a note that hopes of getting “something potato friendly” is low.
  • However, there has been no firm decision, and alternatives were suggested in the meeting, so things are still up in the air.
• Signal Linden requested feedback on the idea of deprecating and removing Navmesh characters / llCreateCharacter (i.e. Pathfinding).

I don’t state the idea lightly, and I understand its low adoption is partially due to a complex and buggy implementation. However, I pulled some data and it appears we have 1,900 navmesh characters across the entire grid. Half of those are ours (Think LL experiences.) There are 6 user-owned regions with more than 10 characters… This is very low usage. I haven’t seen any major merchants release notable content with the system due to its unreliability: but please correct me if I’m wrong.

– Signal Linden

• • Those at the meeting didn’t object to the idea.
  • An alternate approach (“more nuanced” as Signal Linden referred to it, once raised) suggested was to leave server-side the functionality in place and just drop the viewer side, until such time as new ways to handle Pathfinding could be developed.
  • Signal repeated that there are benefits (Pathfinding accounts for a lot of simulator-side code), but that not decision has been made as yet, he is seeking feedback.
  • The subject of Havok in the viewer was raised (used for both Pathfinding and mesh decomposition), with suggestions to replace Havok with the open source HACD library or VHACD (or similar newer implementation), were this to be done.
  • A suggestion was made for TPV developers to bring a HACD / VHACD to the viewer as a code contribution.
• The above lead to a wider discussion on textures (slightly sidetracked by a complaint over the cost of 2K texture uploads for non-Premium + members), and related issues of texture loads on GPUs with limited VRAM,  texture crushing, etc., which continued through the latter part of the meeting.

Next Meeting

• Friday, July 4th, 2025 at the Hippotropolis Theatre – but check the SL Public Calendar for possible changes.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a gathering of people every week. They are taken from my list of region visits, with a link to the post for those interested.