Degrafa Advanced Cubic Bezier
If you update from SVN, you should notice a new class, com.degrafa.geometry.AdvancedCubicBezier. Just as the AdvancedQuadraticBezier added automatic three-point interpolation, AdvancedCubicBezier has four-point interpolation with automatic chord-length parameterization.
I had worked out the math some time ago, but never put the bounding-box methods into the Singularity cubic Bezier class. A bonus for Degrafa users is that I’ve implemented the methods for rectangular bounding of the cubic bezier in AdvancedCubicBezier, as shown in the screen shot below.
A demo for the y-at-x method will follow shortly. In the mean time, you can check out the demo for the other AdvancedCubicBezier methods. As an aside, I uncovered an issue with pointAt() for certain cubic beziers, so AdvancedCubicBezier overrides this method and returns the point directly from the polynomial coefficients.