Day: September 8, 2023

2023 week #36: SL CCUG meeting summary: glTF PBR

Posted on by Inara Pey
Viper Heaven, July 2023 – blog post †

The following notes were taken from my audio recording and chat log transcript of the Content Creation User Group (CCUG) meeting held on Thursday,  September 7th, 2023.

  • 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.

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

  • An update for the PBR viewer – version 7.0.0.581684 was issued following the meeting, on Friday, September 8th.
  • Work is continuing on the communications bloat issue. This will utilise a new message type – GenericStreamingMessage.
  • Bug fixing continues.

Ambient Lighting / Sky Brightness

  • Also noted in previous summaries, there are some issues around ambient lighting where the PBR viewer is concerned. In particular, it tends to render a lot of EEP settings darker than users are used to (in part because the ambient environment lighting in SL has tended to always be over-saturated and bright), and the PBR viewer effectively reverses this to render environments more realistically.
  • This has been an area of work for some time, with none of the results particularly satisfactory, so there is going to be a further round of changes. with the aim of making existing EEP sky settings render more closely to how the author may have intended, rather than remaining overly dark.
  • In addition, the tone mapper in the PBR renderer is going to be adjusted to help reduce undue darkening of older EEP settings.
  • These changes will not impact EEP settings which are created specifically using the PBR settings and capabilities.
  • This work will mean there will likely be a couple more viewer passes as things are tested and adjusted.

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

  • The promised initial build of a PBR viewer supporting mirrors should be made available in week #37. Caveats for this build include:
    • It is not functionally complete and will not render as fully as LL would like.
    • It is not intended for primary use will likely look like it is breaking things.
    • There are already some known crash issues for Mac OS X which will not be fixed when the viewer is initially made available, but will be fixed in due course.
  • The viewer will be made available via the CCUG Discord Channel, and an LSL script will be provided to allow for easy toggling through mirror options.

In Brief

  • Senra:
    • Requests continue to be made to surface the new web-bases avatar creation / customisation tool through the viewer – even it is is just hooking it to the internal browser and providing an easy and obvious means of accessing it. The major reason this is being requested is to to help new users who may have become “lost” or confused in trying to customise their avatar view the viewer – which is clearly a very different experience to the web capability – to get back to something they understand and can readily re-use.
    • It was pointed out that Senra has yet to be featured in the Choose Your Avatar option in the viewer.
    • It was also pointed out that unlike the older “starter avatars” Sentra does not inherently have any form of outfit structure, so if items are worn directly from the Library, anything worn will be copied to the item type folder (shoes to shoes, hair to hair, etc.), rather than being placed within any form of “outfit folder”, making it harder for new users to understand what is happening with their avatar + the items they are using from the Library may end up getting copied multiple times into various folders in their inventory – potentially leasing to more confusion / frustration down the line.
    • This lead to a lengthy discourse through the greater part of the meeting, further demonstrating the need for a New User Experience User Group (or similar) where those actually responsible for projects like Senra could actually engage with users, address questions, etc., rather than cherry-picking if / what they want to respond to via the forums.
  • The above spun-out into a broader discussion on the development of a Sansar-esque dressing room element in the local viewer of outfit / appearance changes (leaving an “untouched” version of the avatar within a region until the change / update is complete) and the complications of doing so (attachments require simulator rezzing, for example), and an general discussion on outfit changes, etc., without firm conclusions drawn.
  • The question was asked about SL supporting vertex animation textures (VAT). This is seen by the Lab as something that might be investigated further down the glTF implementation road, alongside the likes of blend shapes.

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.

Elvion’s ode to Nature in Second Life

Posted on by Inara Pey
Elvion, September 2023 – click any image for full size

It’s been a good few months since my last visit to Elvion, so when Cube Republic sent me a link to an image showing the region’s current iteration, I realised it was high time I dropped in again.

The work of region holders Bo Zano (BoZanoNL) and his SL/RL partner, Una Zano (UnaMayLi), Elvion has tended to shift between Homestead and Full regions, but whichever it has occupied, it has never failed to offer settings of intrinsic natural beauty rich in detail and thoroughly photogenic.

Most often the builds are focus on very pastoral settings, rich in flora and fauna, and sometimes with a lean towards fantasy environments. Some iterations, however, have at times touch on more rural environments – such as with the design the couple presented back towards the start of 2023 (see: Elvion’s coastal retreat in Second Life). With the September iteration, Bo and Una take the region in another direction, offering a setting reflecting the ecological threat of climate change / global warming and the effect it is set to have on the likes of coastal cities and towns.

Elvion, September 2023
With rising global temperatures cities become less habitable. Nature is taking back and people are migrating to the country. Except some, who find peace and see the beauty.

– Elvion About Land

However, this shouldn’t be taken to mean this current iteration of Elvion is in any way a treatise on the threat of climate change and rising sea levels. Rather it is a visual ode to the fact that nature has a way of taking care of her own and redressing the balance when it comes to humanity’s claims on the land, even after those claims may have resulted in the land being ravaged beyond hope.

Elvion, September 2023The core of the build suggests the outskirts of a city or town, probably coastal in nature, and where an elevated freeway once provided rapid access to the heart of the conurbation without a lot of tedious mucking about navigating the gridwork of edge-of-town streets or dealing with locals, the broad lanes of the road instead being raised away from all that to run alongside the rail tracks which once carried goods trains on their backs.

However, the traffic carrying days of both rail and road have long passed; the freeway is in almost total collapse, the rail lines similarly broken and incapable of carrying. Even the buildings rising above or visible from the elevated roadway have clearly been long deserted, with some showing signs of being close to joining some of their brethren in collapse. At ground level, streets have largely vanished, becoming overgrown with weeds and grasses or lost under pools and channels where water has naturally taken command.

Elvion, September 2023

Exactly what has happened here is open to interpretation. Did the sea levels rise sufficiently to start drowning the town, resulting in its abandonment? Did it suffer the battering force of one or more hurricanes or typhoons so severe, abandonment rather than recovery was seen to be the only sensible option? was it broken by the force of a tsunami which originated across the seas but spent its fury here? The story is yours to decide.

What does appear to be clear is that whatever happened, it occurred long enough ago for Nature engage in the long, slow process of reclamation, and is now a good way along that path. The hardtop of roads and parking lots is being taken over by weeds and grass; vines hang from the sides of shops and the barriers guarding the edge of elevated road sections; a children’s play area is now little more than a rusted hulk, its tone matching the majority of the remaining vehicles scattered throughout – some of which are sprinkled across the freeway as if they were, for whatever reason, deserted in a rush by owners and passengers alike.

Elvion, September 2023

Elsewhere the presence of water along some of the depressions caused by former roads is such that little island have had time to be established and freshwater ponds form, offering homes for a range of waterfowl and wildlife. Even the wrecks of vehicles have become so accepted that they are now little more than perches from which heron can watch for signs of passing fish in the waters around them. Bear and beaver are equally at home here now, as are deer, whilst geese find the setting more than acceptable as a stop-over during their long migration flights.

Also scattered throughout the setting are signs that not everyone has fled this place; to the south, for example, someone has created a little homestead for themselves. A wind turbine provides lighting for the simple shack, chickens and goats are being reared, horses looked after (including one that will rez rideable copies of itself, and a canoe is kept in good order, presumably for fishing trips.

Elvion, September 2023

This is not the only sign of human habitation. Elsewhere, someone has built a raft while boardwalks and decks and scattered around on and over the waters, and at least one tree appears to have been felled to create a makeshift bridge over a water channel.  But whether this is all the work of those living at the homestead, or whether it speaks to a little community of people holding-out among the ruins is for you to decide. And given there are these signs of habitation, so too can be found places to sit and pass the time, and appreciate the beauty of the setting.

As always with Elvion, there is a tremendous amount to see and appreciate with this build; far more than either my wittering here or meagre images herein can convey. As such, and as always, a visit is highly recommended.

Elvion, September 2023

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