W3C

– DRAFT –
Immersive-Web WG/CG bi-weekly call

30 May 2023

Attendees

Present
cabanier, CharlesL, Marisha, yonet
Regrets
-
Chair
Ada
Scribe
ada_, bajones, cabanier

Meeting minutes

<cabanier> https://twitter.com/NianticEng/status/1663533912805752832

<cabanier> What is the zoom meeting?

<yonet> https://www.w3.org/groups/wg/immersive-web/calendar

<ada_> Hi, I just rememebered the URL changed to the zoom one and the meeting template has the old URL

Allow adjustment of display time https://github.com/immersive-web/webxr/issues/1328

rik: WebXR gives display time, which is when it thinks the frame will be displayed. Also does reprojection automatically.
… got a question from a streaming service that indicated they needed to do reprojection themselves due to increased latency.
… Rik thinks we could do the reprojection internally, but we need to know when the frame was originally projected to display.
… Proposal is to make the display time writable, needs some reasonable limits (can't do a year in the future)
… OpenXR already supports this

<Koolala> OpenXR also supports requesting XR position data at any frame - does WebXR?

bajones: so the reprojection is an internal detail
… that is based is based on the original projection time
… the page thinks you present in 50ms
… when you present in 55 ms, the delta will be applied to the actual pose
… my question is: it seems that if the original time was xyz, the system would have to recalculate
… I delivered a pose, I delivered a frame back

<Koolala> This slows down a user's input time then - is there a way to get new pose time too?

<Koolala> XR HMD POS -> Server -> WebXR

<Koolala> Could this be done by just lagging your XR app until you get a reply from the server? But that can't work because you can't get HMD / Pos - so it could be for an older XR object like that!

<Koolala> Cloud Multiplayer would totally do reproject on the server too

<Koolala> Declarative Frame Time!

<Koolala> Like CSS!!!

<Koolala> Why can not this be implemented with a Layer like this? Why is there not a WebXR Layer like Quad Layers?

<Koolala> WebXR Layer requests server rendering -> WebXR sends pos -> WebXR gets view from pos lagged in time -> WebXR Layer renders old async render

<Koolala> Async WebXR!

<Koolala> this could work for Modules in JS too! WebXR running in an iframe streaming data into the main system

AOB

<CharlesL> XR Access Symposium June 15/16

CharlesL: I will let you know about the xr access symposion in New York
… they do have subsidized event tickets for non-profits and universities
… I will be speaking on behalf of the social sense XR

ada_: there is a fund for TPAC and they are looking for funding
… if your organization can help attend TPAC, please reach out and propose it

CharlesL: will we have a face to face at TPAC?

ada_: yes. We already have times
… we will have overlap with apa, webapps and webgpu
… and we should also have a meeting with aria

<Koolala> Awesme thanks everyone!

Minutes manually created (not a transcript), formatted by scribe.perl version 197 (Tue Nov 8 15:42:48 2022 UTC).