is3DPoint method
Checks if this point is a 3D point.
Example:
var point2D = Point(3, 4);
print(point2D.is3DPoint()); // Output: false
var point3D = Point(3, 4, 5);
print(point3D.is3DPoint()); // Output: true
Returns true if this point is 3D (i.e., z is not null), and false otherwise.
Implementation
bool is3DPoint() => z != null;