Reddit mentions of 3D User Interfaces: Theory and Practice (2nd Edition) (Usability)

Ignore Carmack (on this one, very specific issue). His conceptual model of what a UI is, can be, and should be, are extremely one directional, vision-centric, and rooted in ancient PARC UIs made for a completely different medium under totally different constraints. VR is a spatial medium by nature, and it simulates the real physical world. In VR, the world IS the interface. You don't need to conceptualize the UI as a separate thing at all. There are only interaction mechanics. You are designing for a mind, not for a rectangle.

To really hammer this home, I recommend studying the following titles:

• Job Simulator
  
  
• Rick and Morty VR
  
  
• Vacation Simulator
  
  And reading the following books:
  
  
• The design of everyday Things by Don Norman
  
  
• The body Has a Mind of its own
  
  
• 3D User Interfaces, Theory and Practice
  
  Be a bit critical of that last one - it's is all very old research. it's good for foundation but do not just copy what they've made, use it to synthesize new ideas.
  
  Leap Motion's blog is also an invaluable source of 3d human computer interaction design wisdom. They recently did a series of interaction design sprints that explore 3d physical interactions
  
  I've also gone through their blog and pulled out a bunch of articles that I found the most interesting and useful in my work:
  
  General design:
  http://blog.leapmotion.com/designing-intuitive-applications/
  
  Fictional UI:
  http://blog.leapmotion.com/fictional-uis-influence-todays-motion-controls/
  
  Vlog FUI pt 1:https://vimeo.com/103174872
  
  https://www.smashingmagazine.com/2013/03/sci-fi-interaction-designers-gestural-interfaces/
  
  3d OS:
  http://blog.leapmotion.com/truly-3d-operating-system-look-like/
  
  Sound in VR: http://blog.leapmotion.com/4-ways-unleash-power-sound-vr/
  
  http://blog.leapmotion.com/explorations-vr-design/
  
  If you get the chance you should play their Blocks demo to see the kind of UX that can teach a completely un-initiated VR user how to interact with a virtual world in an exceptional way. If you really care about HCI, you owe it to yourself to grab one of their devices and go all in on it. It really is an incredible new area to explore and will eventually reveal 2D-only interaction models to be the ancient dinosaurs they are.