Quaternions for Computer Graphics

When events dictated that I would pursue a career in computer programming— rather than electrical engineering—I had no need for complex numbers, until Mandlebrot’s work on fractals emerged. But that was a temporary phase, and I never needed to employ complex numbers in any of my computer graphics software. However in 1986, when I joined the flight simulation industry, I came across an internal report on quaternions, which were being used to control the rotational orientation of a simulated aircraft.