Unfortunately, there isn't a textbook that covers the material in this class the way that I want to cover it. Shirley's book (see below) comes close, when coupled with the OpenGL red book (see below as well). The RTR book (see below) could be a textbook, it covers suprisingly many topics really well. But its a little too focused to be a general textbook.
I provide links to Amazon since they can be cheaper than the UW bookstore - I do not necessarily endorse them.
Peter Shirley. Fundamentals of Computer Graphics, 2ed
note: the new 2nd edition is considerably different than the first - it is green (not orange).
You may get the "uncorrected" 1st printing. If so, please be sure to check the
errata page. In fact, I recommend that you go through the book and mark the errata right away.
Shirley, Foundations of Computer Graphics at Amazon.
Mason Woo, et al. The OpenGL Programmer's Guide.
This is sometimes known as the "red book."
The current edition is the 6th edition, but for the purposes of this class an older edition would be OK too. If you don't want to buy this book, the complete contents of the older version (fine for the required class readings) is online in html. There used to be an online PDF version as well, but it seems to have vanished.
OpenGL Programmer's Guide at Amazon.
There will be some readings from this book, and its an important reference.
Tomas Akenine-Möller and Eric Haines. Real Time Rendering, 2nd ed.
This book is specifically about real-time rendering, and is very useful if you're interested in interactive stuff like games. It is really well written, and has great discussions of a lot of the basic topics. Its getting a little bit dated, but I recommend it if you're really interested in graphics.
Real Time Rendering at Amazon