Month: October 2023

2023 SL SUG meetings week #43 summary

Posted on by Inara Pey
Ashemi Rising, August 2023 – blog post †

The following notes were taken from the Tuesday, October 24th Simulator User Group (SUG) meeting. They form a summary of the items discussed, and is not intended to be a full transcript.

Server Deployments

  • No deployments for the week. However, all simhosts (SLS Main and RC) will be restarted.

Upcoming Deployments

  • The “fall Colours” simulator update is being held back due to a blocking bug which causes the viewer to hang. This requires both a viewer fix and an simulator fix, both of which are in progress. Despite the delay, the hope is to have this release to RC status before US Thanksgiving and grid-wide after Thanksgiving.
  • The simulator-side code for game controller support is also within the “Fall Colours” simulator update.
  • code will also be presented in initial work on updates to the SL damage system – specifically making damage a property of the object (e.g. a bullet), rather than being a script property (see the previous SUG meeting notes and this forum thread discussion) will now hopefully be available for testing on Aditi in week #42 and are being lined-up with the upcoming “Fall Colours” simulator update.
  • The rez_object_fail update planned for the upcoming “Fall Colours” simulator update is likely to slip back to a later simulator release.
  • The ability to turn an avatar invisible when they are sitting is being targeted for a simulator release following “Fall Colours”. This will help address issues such as allowing avatars to sit on small vehicles without them having to be deformed and folded up inside them to fit. This may additionally encompass the likes of feature requests BUG-232678 and/or BUG-233175.

Viewer Updates

No updates to viewers for the start of the week, leaving the official viewer pipelines as:

  • Release viewer, version 6.6.15.581961, promoted October 2 (formerly the Inventory Extensions Viewer).
  • Release channel cohorts:
  • Project viewers:

Games Controller Update

  • The documentation for the Game Controller SL event can be found with the SL wiki.
  • A projects viewer is available via Github actions, but per the above, simulator support is pending the Fall Colours RC release.
  • Pending main grid availability, the simulator support is available on Aditi (the Beta grid) within the following regions: Ahern, Cloud Sandbox 3, Cloud Sandbox 4, Mesh Sandbox 2, Sandbox Wanderton, Snark, and Tyl.
  • Currently, only 6 axes are supported on game controllers.

In Brief

  • A further discussion on combat and games in SL, updates to llDetectedDamage. This includes feature requests BUG-234583 “Detected Damage (combat updates)” and BUG-234584 “Detected Rezzer/Parent (combat updates)” and Linden damage. This also covering projectile rezzing, health regeneration, the ability to hve a Damage event trigger, rules enforcement (e.g. via scripts / experiences), etc.
  • The conversation spun out to touch other areas of interest to, but not reliant on gameplay in SL:  the ability to crawl under objects, an actual crawl option within the locomotion graph, ideas such as feature request BUG-233175 “llSetAgentParams: a way to customize certain agent attributes”, whether or not the existing system for combat should be retained and enhanced or replaced – or a new system introduced with the old behaviours retained for those wishing to continue to use it.
  • Much of the discussion was speculative / requests, and it took up most of the meeting.

† 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 rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

2023 SL viewer release summaries week #42

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, October 22nd, 2023

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.
  • Note that for purposes of length, TPV test viewers, preview / beta viewers / nightly builds are generally not recorded in these summaries.

Official LL Viewers

  • Release viewer, version 6.6.15.581961 (formerly the Inventory Extensions Viewer), promoted October 2 – No Change.
  • Release channel cohorts:
    • Github Actions (GHA) RC viewer, version 6.6.16.6566955269, issued October 20> (with major CEF update and number version numbering).
    • Maintenance V(ersatility) RC viewer, version 6.6.16.582201, October 16.
  • Project viewers:
    • No updates.

LL Viewer Resources

Third-party Viewers

V6-style

  • No updates.

V1-style

  • No updates.

Mobile / Other Clients

  • No updates.

Additional TPV Resources

Related Links

Space Sunday: 3D printing for space, and asteroids

Posted on by Inara Pey
A RAMFIRE rocket engine nozzle performs a hot fire test at NASA’s Marshall Space Centre, demonstrating the viability of 3D printed, aluminium rocket nozzles. Credit: NASA

3D printing may be a relatively new technology, but it is one that is revolutionising may sectors of industry and commerce – and that includes space exploration. I’ve already covered the work of Relatively Space to manufacture and operate the world’s first 3D printed rocket systems in the form of the (now retired after it maiden launch failure) Terran 1, and the highly ambitious, semi-reusable Tarran R. However, NASA has actually been charting the potential for 3D printing in space and on Earth for almost a decade.

As an example of this; the first 3D printing system installed on the ISS arrived in 2014. It was a modest affair primarily designed to research whether or not practical, plastic-based 3D printing could be used in the microgravity of space. As the analysis of the printed parts demonstrated, there were no weaknesses or deficiencies in their construction when compared to identical items produced on Earth using the same process. Thus, the initial project was expanded to encompass the production of usable items – a wrench, plastic brackets, parts of an antenna system, for example – using a variety of industrial-grade plastic filaments.

ESA astronaut Samantha Cristoforetti using the 3D Printer aboard the ISS. Credit: NASA

The capability was then enhanced with the arrival of ReFabricator – a system which could take plastics used on the ISS and recycle them into plastic filament for use by the printer, with Recycler later adding the ability to do the same with other “waste” materials on the station.

In 2023, the European Space Agency and Airbus Industries went a stage further with Metal3D, a printer capable of producing metal and alloy parts for use on the ISS. It is part of a broader project to develop in-situ orbital and lunar 3D printing systems capable of manufacturing everything from replacement parts to entire assemblies such as radiation shields, vehicle trusses, etc. ESA plan to use an enhanced Metal3D system to use lunar regolith as its raw material in the production of equipment and components.

Meanwhile, NASA has also been busy on Earth with a range of 3D printing projects and studies, one of which  – RAMFIRE – which earlier in the year had its (quite literal) baptism of fire.

Standing for the Reactive Additive Manufacturing for the Fourth Industrial Revolution,  RAMFIRE is a unique process which combines an entirely new aluminium alloy called 6061-RAM and 3D printing to create rocket nozzles for space vehicles. To understand why it is potentially so revolutionary, three points need to be understood:

  • As a rule, aluminium is a poor choice for rocket engine (and particularly engine nozzle) construction as it has a rather nasty habit of melting when exposed to high temperatures – such as those generated by a rocket engine nozzle.
  • While aluminium can be strengthened to withstand higher temperatures through the use of additives, the additives themselves can make it susceptible to cracking and microfractures if the aluminium has to be wield to itself or other items as is again required in the production of rocket nozzles.
  • At the same time, being able to print an entire engine nozzle as a single unit and in aluminium, has the potential of both greatly simplifying the process of rocket engine production (as the nozzle now comprises a single part, rather than up to 1,000 individual parts as is currently the case, and for the engine to be significantly lighter without any reduction in thrust, allowing for a potentially large payload to be carried.

Using 6061-RAM with a 3D printing process developed in partnership with Colorado-based Elementum 3D, NASA has been able to produce single-piece aluminium rocket nozzles which, by a combination of the additives used in the alloy and a series of special cooling channels printed into the nozzles, both withstand the heat of combustion in their chambers and also passively cool themselves in the process.

Over the summer period, two small-scale RAMFIRE nozzles were put through their paces at NASA’s Marshall Space Centre in a series of hot fire tests, the results of which were published by NASA on October 16th. The nozzles were tested using two cryogenic propellant mixes – liquid oxygen and liquid hydrogen in one batch of tests, and liquid oxygen and liquid methane in the other. It had been anticipated the nozzles would manage a pressure of up to 625 psi in their chambers, and run for a handful of minutes apiece. As it turned out, they functioned above the anticipated pressure without damage and racked up a cumulative burn time of almost 10 minutes.

This level of burn time and pressure is well in excess of the major requirement for such engine nozzles: within cargo transports carrying payloads to the surface of the Moon and landing them safely, bore lifting off again for the return trip to Earth to collect more cargo. However, the technology being developed by NASA and Elementum 3D has the potential to be used in a wide range of space vehicle applications, from propellant tank manufacture through to providing a means to provide very lightweight, thrust-efficient aerospike engines, one of the holy grails of space transportation systems.

The 6061-RAM2 aluminium and its associated 3D printing process also has the potential to produce other items required by spacecraft. The above is a demonstrator for a single-piece printed propellant tank, complete with the same cooling channels to help keep cryogenic propellants cold. The result is a lightweight single-piece tank structure with primary side walls just 1.5 mm thick.  Credit: NASA

There is still further R&D to go with RAMFIRE, but NASA and Elementum 3D are already looking at licensing 6061-RAM and the printing process to commercial organisations interested in adapting it for use in their space-based efforts  – and possibly further afield in aerospace research sectors.

Continue reading “Space Sunday: 3D printing for space, and asteroids” →

2023 week #42: SL CCUG meeting summary: PBR

Posted on by Inara Pey
Meditation Mountain, August 2023 – blog post †

The following notes were taken from my audio recording and chat log transcript of the Content Creators User Group (CCUG) meeting held on Thursday, October 19th, 2023. Unfortunately, my recording software glitched (I tend to be afk when the meeting is in progress), so only the first 18 minutes of the meeting were actually recorded to disk, as represented here.

  • 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 viewer development work.
  • As a rule, these meetings are:
    • Held in-world and chaired by Vir Linden.
    • Conducted in a mix of voice and text.
    • Held at 13:00 SLT on their respective days.
    • Are subject to the schedule set within the SL Public Calendar, which includes the location for the meetings.
    • Open to all with an interest in content creation.
  • The notes herein are drawn from a mix of my own chat log and audio recording of the meeting, and are not intended to be a full transcript.

Viewer Updates

Friday, October 20th saw the release of the Github Actions (GHA) viewer, version 6.6.16.6566955269. This is the first official viewer to be built via Github Actions rather than TeamCity.

  • Outside of a major version update to CEF (Chromium Embedded Framework) which includes several performance updates and security fixes, this viewer contains no user-observable differences to the current release viewer…
  • .. Other than having even more crunchy digits in the version number for us all to chew on.
  • Release viewer, version 6.6.15.581961, promoted October 2 (formerly the Inventory Extensions Viewer).
  • Release channel cohorts (please see my notes on manually installing RC viewer versions if you wish to install any release candidate(s) yourself).
  • Project viewers:

glTF Materials and Reflection Probes

Project Summary

  • To provide support for PBR materials using the core glTF 2.0 specification Section 3.9 and using mikkTSpace tangents, including the ability to have PBR Materials assets which can be applied to surfaces and also traded / sold.
  • The overall goal for glTF as a whole is to provide as much support for the glTF 2.0 specification as possible.
  • Up to four texture maps are supported for PBR Materials: the base colour (which includes the alpha); normal; metallic / roughness; and emissive, each with independent scaling.
  • In the near-term, glTF materials assets are materials scenes that don’t have any nodes / geometry, they only have the materials array, and there is only one material in that array.
  • As a part of this work, PBR Materials will see the introduction of reflection probes which can be used to generate reflections (via cubemaps) on in-world surfaces. These will be a mix of automatically-place and manually place probes (with the ability to move either).
  • The viewer is available via the Alternate Viewers page.

Further Resources

General Status

  • The back-end communications / bandwidth fix has been deployed to all PBR test regions, per this blog post from the Lab.
  • The push is now on to get glTF PBR to a point where the simulator side code can be more broadly deployed to an RC channel. This may result in some regressions being noted, but this will be subject to point releases to correct, should they occur.
  • On the viewer side, there will be a focus on getting the Mac version up to match the performance seen with the windows PBR RC viewer.
  • Because of the above, and as the viewer moves forward, the recommendation for those testing PBR is to read the available documentation – particularly the viewer release notes.
  • The general word to those testing PBR is that if they do come across anything that could be a major issue, to be sure to Jira it ASAP and in as much details as possible, and if active in the content Creation Discord Channel (which, for those who ask, I have been specifically asked by LL not to provide links to in these pages), to speak up.
  • This focus on trying to get PBR Materials out means that the work on real-time mirrors and on glTF terrain has been put on a temporary hold to maximise the resources available for Materials work.

Mirrors

  • Mirrors are a part of the glTF / PBR materials project, but something of a separate tranche of work.
  • The idea is provide the means to have via high resolution reflections (i.e. mirrors) within a scene.
  • Initially only one active mirror surface per scene will be active for any viewer.
  • The process will use the PBR reflection probes mechanism, combined with a automated “Hero Probe” mechanism which with generate high resolution (512×512) “reflections” for the mirror.
  • The system will operate on the basis of avatar / camera proximity to a mirror surface triggering the closest reflection probe to become a “Hero Probe” for that avatar / camera. This means that if there are multiple mirrors placed within an environment, only the one closest to a given avatar / camera will be active and display the “reflections” generated by the reflection probe.
  • Depending on testing and performance, the number of mirrors might be expanded to two – one for mirror surfaces and one for Linden Water to generate high resolution water reflections where appropriate.

Status

  • As noted above, work temporarily on hold to focus resources on PBR Materials.

In Brief

  • There was a general discussion on how best to change an preserve overrides on materials when allowing for the likes of colour changes when making changes via LSL (and how best to batch similar changes). This was seen as something that could be better handled outside of LSL directly (thus avoiding multiple calls to set / preserve specific changes), but is something to be looked at after the initial release.
  • At this point the recording flatlined 😦 .

Next Meeting

† 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.

Autumn’s Where Our Journey Begins in Second Life

Posted on by Inara Pey
Where Our Journey Begins, October 2023 – click any image for full size 

It’s been almost a year since my last visit to Vivian Ewing’s Where Our Journey Begins. At the time of that visit, the region was dressed for winter 2022, and I wanted to catch it before the autumnal setting vanished in favour of something more in keeping with the turn of the year – and in the process adding autumn to my previous posts on the region, I will have now covered all four seasons at the region.

For autumn, Vivian has turned to a palette of hues and colours common to the time of year – yellows, browns, splashes of greens, reds and so on, which extend into the environment settings for the region as well, the sky cast in bronze on the horizons, darkening as it moves overhead before brightening once more, the clouds a patina of orange and yellow, dark underbellies hinting at the prospect of rain.

Where Our Journey Begins, October 2023
And the sun took a step back, the leaves lulled themselves to sleep, and autumn was awakened. Immerse yourself in a world full of autumnal colours and peace.

– Where Our Journey Begins, autumn 2023

To the north the lands are raised, curtain walls of cliffs helping to both separate them and bind them with the off-region surround to east and west. A tramway bursts forth from the western cliffs, exiting a tunnel mouth to pass between the tall arms of a grand wrought-iron bridge raised on tall stone-faced plinths as they across the river splitting the land in two from north to south, in the process spanning a shallow valley as it cups the waters in its arms.

Where Our Journey Begins, October 2023

Across this bridge – which is joined in spanning the river valley by an equally wide boardwalk on its own row of footings as it forms a pleasant place on which to stroll and watch the activities on the water below – sits a small borough fashioned around a central square. The modern 2- and 3-storey buildings arranged around three sides of the square suggest that this is part of a larger township even whilst it stands alone. The square itself is given over to a very pleasant café with seating indoors our under its broad awning. With the local clock tower standing guard alongside the café and the screen of surrounding trees illuminated by strings of lights winding through their boughs with leave turned to rust, it the square has a certain sense of romance about it.

Facing the café is a brick-built rich providing access to a shoulder of hill sitting above the river. The arch provides access to a path as it meanders around the hilltop, providing a suitable walk for lovers complete with a romantic folly presiding over things at the top of a raised thumb of rock. Those taking the path with find it circles half-way around the folly on its proud seat, then descends down towards the river.

Where Our Journey Begins, October 2023

Here the waters appear to have narrowed rapidly after passing beneath the bridge to the north, the ground lush with grass, the water a narrow ribbon running between banks. However, looks can be deceptive – as the slender boardwalk running out from behind a riverside  deck and hot tub quickly reveals. Rather than growing along the eastern bank of the river, the grass in fact marks the presence of a lush, shallow wetland extending out into the main channel of the river, a wetland which continues south, trees rising from its waters and its actual edge marked by a drystone wall as it borders the track running south from the foot of the folly’s hill.

A second narrow boardwalk spans the river towards its southern end, where the lowlands spread outwards to east and west, looking like golden pastures while again actually being a mix of solid ground and wetland under the carpeting of grass. To the west, the lowlands flow past another raised shoulder of land bordered on two of its remaining side by the aforementioned stream (itself crossed by a very sturdy wooden bridge which has seen much use / repair over the years). This triangle of land is home to a small ranch / farm, complete with a horse rezzer for those wishing to take a ride.

Where Our Journey Begins, October 2023

Those who do might try their hand at herding the cattle wandering along the local track – or perhaps head south and east to see if they can persuade the cows grazing out on the grass of the lowlands that it is perhaps time to come home! If such an exercise does not appeal, then a walk / ride along the dirt road running east will bring visitors to a low-slung bridge spanning the narrow neck of an inlet cutting into the land. With an old wooden gazebo and a hut-like tent offering places of retreat, this is again perhaps a location for those with a romantic heart.

With a modest farmer’s market (with a touch of quirkiness in it – those staffing the stalls appear to be some of the local deer and squirrel populace!) also sitting along the track leading to the inlet, these is much more to be found along the southern side of the region than might initially appear to be the case. As always, Vivian has certainly created a rich, photogenic setting ripe for exploration and spending time within – so enjoy it before winter steps in!

Where Our Journey Begins, October 2023

SLurl Details

2023 SL SUG meetings week #42 summary

Posted on by Inara Pey
Dwejra, August 2023 – blog post †

The following notes were taken from the Tuesday, October 17th Simulator User Group (SUG) meeting. They form a summary of the items discussed, and is not intended to be a full transcript.

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.
  • These meetings are conducted (as a rule):
  • They are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
  • Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Server Deployments

  • No deployments for the week (again). However, all simhosts (SLS Main and RC) will be restarted.

Upcoming Deployments

Viewer Updates

The current batch of official viewer versions is as follows:

Potential for Games Controller Use

  • This work sees the introduction of a new LSL event called game_control, the format for which Leviathan defined as:
game_control(key id, list buttons_edge_down, list buttons_edge_up, list buttons_down, list axes). Lots of lists, but that was necessary to support treating the keyboard as a “big controller with lots of buttons”. I created some docs for the game_control stuff on the LSL wiki.
  • Leviathan also noted there should be a GameControl category page, at the time of writing the link to it had yet to be added to the game_control wiki page.
  • The server work is now considered wrapped, and the focus is on the viewer support.
  • Overall, the work is seen as an initially simple pass to provide basic support for the use of game controllers in SL and intended to get things rolling; so capabilities such a building a “virtual game controller”, as requested at previous meetings are not available. However, he noted that, “Once the network protocol is nailed down and the script stuff… it will still be possible to modify the viewer. “
  • Key points of note include:
    • The feature doesn’t require permissions, but can be enabled via checkboxes in the viewer UI. However, Leviathan noted it could be piggybacked on controls permissions.
    • Subject to testing, the keystrokes are the remapped ones according to other UI settings.
    • The capability currently only works for attachments and seats, it cannot be used for avatar movement.
    • Doesn’t as yet support controller gyro, or rumble feedback nor support for trackpad position for game controllers that have it, nor does it support the use of mouse position recognition and buttons.
    • The above two points have a potential to be added later, “perhaps”.

In Brief

  • The official blog post on the deployment of a simulator update to resolved the communications / bandwidth issue referenced in recent CCUG meeting summaries was referenced.
  • Two feature requests for avatar movement were raised – BUG-234557 and BUG-233175 – leading Rider to note:
Adjustable avatar movement would be possible… the only thing about it that gives me pause is… I know how delicately tuned the avatar motion logic is under the hood, to allow for walking up low ledges, friction when stopping, and how the avatar tries to stand still when at rest but still be “bumpable” by other avatars and objects.

This led to an extended discussion on avatar movement and options for allowing the use of a velocity model for avatar movement (thus allowing for avatars moving at different walking speeds, etc). This lead to a broader discussion on avatar movement / animations, etc., which touched on the dormant puppetry project.

  • HTTP work. Rider Linden noted he is back to working on his HTTP code and simulator asset handling refactoring, and is hoping to get the underpinning code refactor completed in the next week(ish) and then work on the asset management side. This led to a request for the issue of Modify items becoming labelled as No Mod for the owner when a No Mod item is place in its contents & then taken back to inventory (even though the item still have Modify permissions), which in turn generated a request for a Jira report.

† 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 rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.