This means I can now process events like turning the scrollwheel on the mouse, or click-dragging with a modifier key held down - events which were inexplicably missing from GLUT. However, it turns out GLUT is actually about ten years out of date, so I suppose scrollwheels probably didn't exist when the last GLUT version was released.
In other news, Bézier curves are well and truly on their way! I finally got some code written today, which includes all the drawing functions, some basic event handling, and a sufficient helping of behind-the-scenes faffery. Here's a screenshot:
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More next time!