[VR-Centric] Motion controller latency questions

Just a few basic(?) questions in regards to motion controller latency:

  • What is considered a comfortable time frame between actual input -> game action?
  • Is it possible to use late-latching and/or prediction (the same things that HMD’s use) for controllers? How would it affect the game’s overall latency?

On a side note as well, I remember seeing, awhile back in a news article (non-Epic), that some researchers (somewhere) found/created a material that increased/decreased flexibility/hardness when electrical current was passed through it… anyone remember where that was?