We wrote some code in class to implemented basic parametric surfaces.

In class we showed how to implement the simplest parametric surfaces, including cylindrical tube, spherical globe and torus (or bagel, if you are a New Yorker).

In every case, we wrote a function that maps any [u,v] to a point in space [x,y,z], where u and v each vary between 0.0 and 1.1.

For example, here is the function we implemented to describe a parametric spherical globe is this:

   function globe(u, v) {
      var theta  = 2 * Math.PI * u;
      var phi    = Math.PI * (v - .5);
      var radius = Math.cos(phi);
      return [
         radius * Math.cos(theta),
         radius * Math.sin(theta),
         Math.sin(phi)
      ];
   }

The code we wrote in class is here.