Cubic fractal sponge. See for comments
WebGL Tetrahedral sponge.
You can set a new recursion number value (for N = 5 there are 32768 points, N < 7).
Tested on Oculus Go (with touchpad) and VR BOX2 (with joystick).
For tests on a desktop (Windows 10 + Chrome) the "inline" webxr session
are used.
WebXR samplesupdated 6 July 2020