If you have a newish Android smartphone, I can confirm that Elite works with Google Cardboard! So you can now try the full VR experience with headtracking for about £20!
I haven't tried an Oculus Rift DK2 yet, but positional tracking is absent (rotation only) and performance is surely worse. I'm using a Nexus 5 phone, so the resolution is the same as the Oculus DK2 (1920x1080), but my graphics card (old 1gb Radeon HD 5700) is too weak.
The glorious software to make this happen is Trinus Gyre:
http://oddsheepgames.com/?page_id=134
I've also only just started tinkering with Trinus Gyre, so further advice on using it with Elite is welcome. This is what I have so far:
Pre-requisites
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Elite, Android phone, Google cardboard or similar
Install software
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Install Trinus Gyre on your phone from the Play Store (start with test version):
https://play.google.com/store/apps/details?id=com.loxai.trinus.test
Install Trinus Gyre server on PC. Download:
http://oddsheepgames.com/?page_id=155
Install OpenTrack for facetracking:
https://github.com/opentrack/opentrack
Configure
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Start the Trinus server on your PC and the app on the phone. Input your PC's network IP on the phone. On my system, they connected without any problems, but you might need to fiddle around a bit here. Open firewalls as needed, etc. See Trine Gyre website and forum for help. The USB tether option gives better performance than any wifi connection option.
On the Trinus server, select "OpenTrack Redir" for sensor type. Other protocols might work as well.
In the phone app, select Lens Off.
Start OpenTrack. For Main Tracker, select UDP. Under settings select 5556 for the port number (or whatever Trinus uses for "sensor port"+1). For the Game protocol, select FreeTrack 2.0. Select Mapping, and set 1:1 graphs for yaw, pitch, and roll (a straight line from the bottom left to the top right). Under the options tab, I had to invert yaw, but that might not be necessary for everybody.
Start Elite. In graphics options, select windowed and side by side. I had to lower resolution a bit to get it to work smoothly, but that will depend on your PC. Trinus eats half my CPU (old AMD quadcore), so framerates suffer. For me it looks better by reducing the field of view a little.
Running it all
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Close everything. Restart in the following order.
1) Open Trinus server and app. Connect, but don't select software yet.
2) Open OpenTrack. Click Start. Check that you can see numbers coming in for yaw, pitch and roll when you move the phone.
3) Start Elite (now windowed)
4) Select Elite (CLIENT) in the Trinus server selection window.
Marvel at true VR. I still haven't used it much, but I don't think I'll play with this continuously. Since I had to lower resolution, I can barely read UI text and my CPU is rather suffering. But it's fun to play around with, it really works, and it's an incredible experience the first time.
