paper.js

Ooh, the Chebyshev basis is neat. I hadn't seen exactly that before. It reminds me a lot of the "shape control" technique[1] which is also similar to a basis function approach but has a bit of linear solving. Essentially, you get one point (usually at t = 0.5), and also the direction but not magnitudes of the tangents at the endpoints (G1, not C1). This is one of the better-performing existing techniques for offset curve, though does have stability problems (in particular, nasty behavior for a symmetric "S" curve). Regarding collaboration with Freya, if she is open to it, please get in touch. I do have some ideas. [1]: A New Shape Control and Classification for Cubic Bézier Curves, Yang and Huang, 1993, PDF cache: https://github.com/paperjs/paper.js/files/752955/A.New.Shape...

Optimization decisions that V8 team have made are much more universal than it might seem. That's certainly possible, but maybe a competing VM can do better, but finds that everyone has coded specific V8 optimizations. They may be hesitant to push out their implementation. It may be a better optimization, but it causes existing code to run slower on their VM. Thus back to the original statement that implementation quirks find their way into developer code. for (IWantThisVariableToEndUpOnGlobalObject in obj) { } The variable has to be in the local scope and can't be in any higher or lower scope, not just a global scope (which your words acknowledge, but your code snippet doesn't). It's easy to end up sending the prop variable through a closure accidentally. Some real world examples[0][1][2]. Note that the solution requires pushing out

Paper.Js https://github.com/paperjs/paper.js Interact.Js https://github.com/taye/interact.js