C# creating the parametric equations for a cube

Hi All,

I am trying to write the parametric equations for a cube in C# and am a little confused as I have not written any script before. I think the function equation for a cube is

function { max((y*y-1),(x*x-1),(z*z-1)) } but i am struggling to translate it into the necessary parametric equations. Please see grasshopper file attached.

I am trying to hack a Millipede example and replace the example gyroid formation with a cube. I am not even sure if it is possible. Hopefully someone can point me in the right direction. 

Thanks for your time

Tim