Public Function AddByStartEndCenterNormal( _
   ByVal Startx As Double, _
   ByVal Starty As Double, _
   ByVal Startz As Double, _
   ByVal Endx As Double, _
   ByVal Endy As Double, _
   ByVal Endz As Double, _
   ByVal CenterX As Double, _
   ByVal CenterY As Double, _
   ByVal CenterZ As Double, _
   ByVal NormalX As Double, _
   ByVal NormalY As Double, _
   ByVal NormalZ As Double, _
   ByVal dRadius As Double _
) As Arc3D