plotting 3-d surface from data in irregular set

I have a set of values generated by a surface fitting program that I want to view as a 3-d surface. The MathType is ((x,y)-> z). I'm using an irregular set for the domain created with an array of floats from the data generated by the surface fitter. I can plot the data as points, but I can't figure out how to get VisAD to connect the points and create a surface. I've tried looking at the examples, but none of them use irregular sets. Is it not possible to plot a surface from an irregular set? I'm pretty sure I have to use an irregular set because the points from the surface fitter aren't guaranteed to be at regular intervals.

Thanks for the help,
Susanna Ricco