Sorry for reviving this old thread, but I've done some research myself and don't want it to go to waste. Because I'm not affiliated with HTC/Vive in any way, take everything I say with a grain of salt 😉
@robo_doc there is some confusion around this topic, and it stems from this issue: It seems that HTC built in a standard Tobii tracking USB chip, which is directly supported by *all* Tobii SDKs. Even the free ones. Sadly, they stopped offering Linux support, but an older version is still available on GitHub. However, the Tobii chip is powered off or disconnected by default and needs to be switched on - by, you guessed it, HTC software. So the answer to the dependency question is that you need both: HTC would need to release a small utility that turns on the eye tracker and Tobii would need to continue their Linux support (although the old version works fine). That would be a minimal solution that would avoid porting and supporting the entire SRanipal software stack.
It might be possible to write such a "enabler utility" yourself and enjoy eye tracking under Linux.
