I can't recommend this book enough. For anyone looking for a more gentle introduction into ray tracing, I'd also suggest The Ray Tracer Challenge (http://www.r

I can't recommend this book enough. For anyone looking for a more gentle introduction into ray tracing, I'd also suggest The Ray Tracer Challenge (http://www.raytracerchallenge.com/ http://www.raytracerchallenge.com/) -- it walks you through building a simple recursive ray tracer in a test driven development manner. I started with the RTC, and moved on to PBR - and converting my recursive tracer into a unidirectional path tracer was quite an adventure -- one that continues to this day.