Some more skeletal work, and trigger values

Open mlugg requested to merge mlugg/OpenOVR:feat/aux-bones into openxr
  • Floating trigger values can now be fetched through the legacy input system. This previously only worked for controllers where click and value aren't distinct, since the existing code assumed the binary value was also used for the float.
  • Skeletal aux bones are now implemented in what I believe to be the correct way (they just mirror the model-space distal bones).
  • I did my best to implement finger splay into skeletal summary data, no idea how well it works.
  • I implemented "compressed" skeletal data, although it doesn't actually compress it, it just sends the raw data over the wire. Better than nothing.

DO NOT MERGE WITHOUT TESTING!! I don't have access to my headset at the minute so haven't been able to test these changes beyond checking they compile. SUPERHOT VR can be used to test skeletal summary data (finger splay), but I'm not sure which apps exist that utilize the other bits.