Quad.copy constructor
      
      Quad.copy(
    
- Quad other
Create a quad as a copy of other.
Implementation
Quad.copy(Quad other)
    : _point0 = Vector3.copy(other._point0),
      _point1 = Vector3.copy(other._point1),
      _point2 = Vector3.copy(other._point2),
      _point3 = Vector3.copy(other._point3);