I received emails from some readers of my previous Game of life on spheres post, asking about the detailed explanation of the code, which I would really love to do. But before going into sphere case, I think it should be more intuitive to get a feel of tensor product spline surface through simple circle and straight line. So here is it: a simple walkthrough, along with a bunch of rotating concentric cylindrical patches to showcase the outstanding 3D performance when we use BSplineSurface instead of, say, ParametricPlot3D.
