LaTeX.org

Another way to do this is to plot the function of a quadratic bezier curve in Bernstein form.

a 1d explicit quadratic bezier function looks like this:

y = A*(1-x)^2 + B*2x(1-x) + C*x^2

I just did that to get a 1d bezier curve diagram for my paper. Not sure if tikZ can plot multi-dimensional ...