New Year VR Question

Happy New Year Everyone!

I have been real quiet these couple of months working on a variety of 
projects. Part of that time has been thinking about handling Declarative 
VR in the browser. In particular what should happen when the web page 
requests a VR display, but the device is not VR capable. For example in 
a modified version of the THREE boxes example (see ) a button is put on 
the bottom of the display allowing the display to go into VR mode (if 
possible) or indicating that a VR device is not available.

The user may have a phone with only cardboard. Cardboard is not 
considered a VR device (at least in context of WebVR). It is still 
possible to get a VR experience.

If a programming environment such as THREE, that can be detected and 
other options offered. In a strictly declarative environment, that 
capability is not available. Should a Declarative VR language

 1. automatically roll-over to a stereographic display
 2. provide an ordered list of fallback options
 3. only do exactly what is requested (no VR device ==> no VR display)

Note that (3) is not necessary exclusive of (2).

If (2) is the desired capability, then how is that best represented - as 
an attribute list ("option1, option2, ..."), a single fallback 
attribute, an ordered list of children tags?


-- 
*Leonard Daly*
3D Systems Architect & Cloud Consultant
President, Daly Realism - /Creating the Future/