Functions of two variables can be visualized in many ways: heat maps in 2D, contour curves in 2D, wireframes in 3D, surfaces in 3D. We begin by defining a function of two variables, building an array ...

but only trying to describe the surface of an object. The empty space around it and inside it? Doesn’t matter. So first his system renders a 3D reconstruction of the 2D image in very low resolution.