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by prospero 2179 days ago
Hi, author here. I looked into that side of things, but CGAL only offers exact precision implementations for lines and circular arcs. The fact that Bézier curves are left as an exercise for the reader is further proof of the disconnect between computational geometry and modern computer graphics.
2 comments

Fair point. At the same time the exact computation paradigm is proof that problems like these can be solved in a rigorous way if you start with the right foundation.

By the way thanks for writing the article, it was a refreshing read.

I'm curious; I've played with OpenSCAD a little, which uses CGAL, and found it to be painfully slow (with no particular point of comparison). Do you think you have a way to do similar CSG calculations faster, or at least trade speed for accuracy or something?
It's very plausible that these techniques could be used to fix the output of a CSG library that uses floating point math, but I'm not sure what the specifics would look like. If anyone has ideas in that vein, I'd be very interested to hear them.
I was thinking along the lines (based on skimming documentation) of CGAL using arbitrary precision integer based rationals, which are slow, and using floating point with the error correction might potentially be faster.

Unfortunately, it's probably way beyond my ability to delve in to it.