De Casteljau's algorithm
De Casteljau's algorithm for splitting n-th degree Bezier curves. Control points can be 1 or 2 dimensional, thus x only or [x, y] vectors. Does not return the values of a Bezier curve at a given point, but rather the correct new control points of the resulting partial curves, if the Bezier curve is split in two curves at the given point. This allows for animated drawing of Bezier curves as well: simply split at the point up to which you want to draw and only draw the first resulting curve, repeat on every animation frame while advancing the split point.
But beyond the well known "animated drawing of Bezier curves" scenario, this code also serves cases where you just want to have the control points of the split curves, not curve values. The whole thing is not optimized for speed but readability. See it here!