3D Math Primer for Graphics and Game Development

Appendix A

Math Review

This appendix presents a brief review of some key mathematical concepts. Other information can be found on the web page for this book, gamemath.com.

Summation Notation

Summation notation is a shorthand way to write a sum. Summation notation is like a mathematical for loop. Let’s look at an example:

The variable i is known as the index variable. The expressions above and below the summation symbol tell us how many times to execute our “loop” and what values to use for i during each iteration. In this case, i will count from 1…6. To “execute” our loop, we iterate the index through all the values specified by the control conditions. ...