Nvidia is excited about raytracing, to say the least, but they still face some hurdles in getting the industry to adopt it. In that vein, Nvidia is writing a entire book on raytracing. In addition to (presumably) selling a print copy in stores, Nvidia is uploading PDFs of the book for free in the Nvidia Developer Zone. At first glance, it may look like the downloads are behind a paywall, but signing up for a Nvidia developer account is relatively painless and doesn't cost anything. For reference, Part 1 is already 81 pages long, and while the a large portion of the first entry is taken up by contributing writers (which, interestingly, includes a Mass Effect/Dragon Age developer and some other high profile names,) the rest of the article is densely packed with developer info and example code. Thanks to cageymaru for the tip. These chapter are "preprints," in that they will look a bit different than the publisher's layout, but the information is the same, barring any last-minute fixes. By the end of February, the professionally laid-out electronic version of the final book from Apress will be available for free (formats to be determined), along with the code repository. Ray Tracing Gems is not meant as a survey of the field of ray tracing. There are already fine books that provide a general education, many of them free; see this resource list, for example. Rather, this volume is more in the spirit of other gems books, such as GPU Gems, containing articles covering techniques that are often not discussed in general texts but that are important for high-quality results. The book also includes tutorials on newer technologies, along with guides that pull together best practices for solving specific problems. The second half of the book includes studies of larger systems focused on a variety of effects.