Tangentially, huh? So the underlying operation of finding a parallel "curve" is trivial when the curve is a line, as it's just another line. That doesn't mean

Tangentially, huh? So the underlying operation of finding a parallel "curve" is trivial when the curve is a line, as it's just another line. That doesn't mean the problems is simple, though. One challenge (which I didn't address in the post, nor do I have code yet) is dealing with corners, as there are the usual choices of round, miter, and bevel. Of these, only round represents a true Minkowski sum. The others are generally more commonly used. Btw, see "Polar Stroking" [1] for more details on this. I came very close to linking it. The second detail is the "trimming" as the parallel curve paths generally have self-intersections, and very often you don't want those. So in the general case you have to do something similar to, say, Skia path ops. It's very difficult to make those operations completely numerically robust, and I think most implementations have gone through some pain as more test cases pop up which break. It is a fascinating area. I'm glad you're curious. [1]: https://arxiv.org/abs/2007.00308 https://arxiv.org/abs/2007.00308