Function negate

negate(out: plane3.Plane3, plane: plane3.Plane3): plane3.Plane3
Negates a plane (flips the normal and constant)
Parameters
- out: plane3.Plane3
  The output plane
- plane: plane3.Plane3
  The input plane
Returns plane3.Plane3
The negated plane
- Defined in shapes/plane3.ts:131