Electrical engineer and FOSS developer Charles Lohr (@CNLohr) has been reverse engineering raw Vive data. In a recent live-stream, of which a recording is available at YouTube, he explains and demonstrates basic reverse engineering (decoding) of USB light data reported by the Vive controllers. Not only was CNLohr able to make some discoveries, Ben Jackson, engineer at Valve Corporation, also dropped in as a viewer of the live-stream and was able to provide some direct information.
CNLohr has a goal to use the Vive on Linux with his older, non-gamer laptop with a room-scale VR environment. Though other GPL FOSS projects are geared for running the Vive on Linux and other operating systems, CNLohr is specifically looking to have a C library that minimizes size and dependencies as well as being licensed under the more permissive MIT license.
Charles LohrOne of the biggest driving forces for me was to get away from this world of huge dependencies, because I actually ran out of data on my cell phone plan trying to get all of the dependencies needed to build and use OSVR-Vive-Libre. The second is that I am a C programmer, through and through. All of the current implementations are very heavily object oriented with all sorts of elaborate architectures. I just want a simple library I can include, and use the Vive.