SH16 cycling near hit, still here thanks to rear view mirror

I nearly didn't go this way today, just to avoid crossing this SH16 roundabout, but traffic was light. Thankfully I saw a black car cutting across to do an illegal left turn (from the right/straight lane) in my "Take a Look" rear view mirror and, just, braked in time to avoid getting hit.

 

Front and rear Cycliq camera caught views of this incident, the gap was literally mm.