Beta (Inputs.Base)Betaf64Coordinates: flat x, y pairs for polygons, x, y, z triples for triangle positions and
sixteen numbers for each frame of a loft. Every number in it is a coordinate, finite and
between minus and plus one billion.
Betai32Triangle corners as positions counted from 0, three per triangle.
The numbers a recipe's nodes point into: coordinates in
f64, triangle indices ini32.