I’ve never seen this before, a Humble Bundle of all sorts of computer graphics books. $8 for Ray Tracing from the Ground Up, OpenGL Insights, and Real-Time Shadows (and nine other books also of interest) is quite the deal. Kick it up to $15 and you get 19 books. I just did and it was painless: it’s a few minutes later and I now have 18 PDFs of these books. (Thanks to Patrick Cozzi for the tip-off.)