I purchased the paper version :-)

There is for me a special connection between this book and https://www.amazon.com/Advanced-Animation-Rendering-Techniqu... - in the way they connect to the underlying knowledge in a deep way.

This topic is such a sweet rabbit hole to me!

Before I developed a serious rendering engine, I'd read Advanced Animation & Rendering Techniques by Watt & Watt [1], cover to cover, a dozen times. It's pretty dated now, but at the time I first acquired it (90s) it was the most comprehensive overview of rendering I knew of. I'd also read Real Time Rendering, and Math for 3D by Lengyel, which are both on this list. For really proper collision, Real-Time Collision Detection (on the list) was absolutely invaluable, but I didn't get to that until a few years later. Around that time, I also read the excellent architecture book Game Engine Architecture [2] which I don't see here. It's well written, does things in the right order, and it's very comprehensive.

[1] https://www.amazon.com/Advanced-Animation-Rendering-Techniqu...

[2] https://www.amazon.com/Game-Engine-Architecture-Jason-Gregor...