类: CSG.Vertex

class Vertex

Represents a vertex of a polygon. Use your own vertex class instead of this
one to provide additional features like texture coordinates and vertex
colors. Custom vertex classes need to provide a `pos` property and `clone()`,
`flip()`, and `interpolate()` methods that behave analogous to the ones
defined by `CSG.Vertex`. This class provides `normal` so convenience
functions like `CSG.sphere()` can return a smooth vertex normal, but `normal`
is not used anywhere else.