Circles shouldn’t be this hard

For my project for my History class, I’m writing a computer simulation of (among other things) Ptolemy’s model of the solar system. Ptolemy’s model is based entirely on constant circular motion. Since the sun, moon, and stars don’t actually travel on circular paths, the model does things like having a planet move around a circle, and the center of that circle moves around another circle, and that circle’s center is offset by a small amount from the Earth.
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