enneagon

I'm just following makerblock's openscad tutorial, and making things. For some reason I cannot recall or explain, I became obsessed with making a pentagon while doing the 2D section. I've tried making one a few different ways, but then after reading more of his tutorial, I went back and did it with four rotations of a triangle. once that worked, I modified it to be a nine-sided figure (apparently properly called an enneagon), and now I'm posting it to say "look at me! I'm openscad'ing!"

UPDATE
Now with added parameterisation!