You're looking for information on the book "Fundamentals of Computer Graphics" 5th edition, and specifically, a downloadable PDF version. Here's what I have to share:
The 5th edition of "Fundamentals of Computer Graphics" was published in 2016 by A. K. Peters/CRC Press. The book is authored by Steven J. Harrington, but I couldn't confirm if he is the sole author or if there are other contributors.
As for a downloadable PDF version, I couldn't find any officially available or free PDF copies of the book. The publisher and authors usually protect their intellectual property by not making PDFs of their books publicly available.
"Fundamentals of Computer Graphics" is a popular textbook that covers the basics of computer graphics, including graphics systems, graphics programming, and graphics algorithms. The book is widely used in computer graphics courses and is known for its clear explanations, examples, and exercises.