@slippyfish:
I meant the concept of “solids” as some novel way of generating geometry is misleading, because it is. “Solid modeling” is a workflow method, controlled at the software level, not at the geometry generation level. New versions of SW aren’t just now incorporating NURBS features; they’re implementing NURBS ideas that have been around for ages (see: Alias), but SW is just now figuring out a way to implement them without wrecking the solid-modeling style.
So really the idea of Parasolid is not relevant to the concept of geometry calculation. Generically, Parasolid is a kernel which means it’s basically an interpreter. It takes the math of spline boundaries and says “Hey software, here’s what you’re dealing with” and then the software handles the display and manipulation of that data.
All of this put more succinctly by JimC5…
Good description by nxakt too