Defines the smoothing type that is applied to objects. Default value is SmoothingGroups that uses the Smoothing Groups values stored in 3ds file to define which edges are smooth and which are flat. The SmoothingGroups value produces the results as in the 3d model designer. However if you wish to force the flat or smooth looking objects choose either Flat or Smooth. Also if performance is much more important than rendering quality choose None.

public Reader3dsShadingType Shading { get; set; }