OrientationsViewer  [--returnparameterfile <std::string>]
                       [--processinformationaddress <std::string>] [--xml]
                       [--echo] [--angle <std::vector<double>>] [--window
                       <std::vector<double>>] [--combine] [--sphere]
                       [--mesh] [--nopoints] [--pointType <VERTEX|SPHERE>]
                       [--radiusSphere <double>] [--sizeVertex <double>]
                       [--radiusFile <std::vector<std::string>>] ...
                       [--radius <std::vector<double>>] [--opaSphere
                       <std::vector<double>>] [--opaMesh
                       <std::vector<double>>] [--color
                       <std::vector<double>>] [--bg <std::vector<double>>]
                       [--nosym] [--png <std::string>] [--] [--version]
                       [-h] <std::vector<std::string>> ...


   --returnparameterfile <std::string>
     Filename in which to write simple return parameters (int, float,
     int-vector, etc.) as opposed to bulk return parameters (image,
     geometry, transform, measurement, table).

   --processinformationaddress <std::string>
     Address of a structure to store process information (progress, abort,
     etc.). (default: 0)

     Produce xml description of command line arguments (default: 0)

     Echo the command line arguments (default: 0)

   --angle <std::vector<double>>
     azimuth and elevation for camera. (default: 0.0,0.0)

   --window <std::vector<double>>
     window size. (default: 600,600)

     True: only show the combined shell from multiple shells. (default: 0)

     True: show sphere. (default: 0)

     True: show Delaunary mesh. (default: 0)

     True: do not show points. (default: 0)

   --pointType <VERTEX|SPHERE>
     Type of points. Vertex or sphere. (default: SPHERE)

   --radiusSphere <double>
     radius of sphere for points. (default: 0.04)

   --sizeVertex <double>
     size of vertex for points. (default: 5)

   --radiusFile <std::vector<std::string>>  (accepted multiple times)
     Input radius File. One radius for one point.

   --radius <std::vector<double>>
     radius of the sphere. (default: 1.0)

   --opaSphere <std::vector<double>>
     Opacity of the sphere. (default: 0.5)

   --opaMesh <std::vector<double>>
     Opacity of the Delaunary mesh. (default: 1.0)

   --color <std::vector<double>>
     color for each shell (default: 1,1,1)

   --bg <std::vector<double>>
     background color for the window (default: 0,0,0)

     False: add both input points and their antipodal symmetric points.
     True: only add input points. (default: 0)

   --png <std::string>
     Output png File.

   --,  --ignore_rest
     Ignores the rest of the labeled arguments following this flag.

     Displays version information and exits.

   -h,  --help
     Displays usage information and exits.

   <std::vector<std::string>>  (accepted multiple times)
     Input Orientation File.

   Description: Single and multi-shell orientations viewer.


   OrientationsViewer grad1.txt --mesh

   OrientationsViewer grad1.txt grad2.txt --combine --mesh

   OrientationsViewer grad1.txt grad2.txt --combine --mesh --png

   Author(s): Jian Cheng (jian.cheng.1983@gmail.com)

   Acknowledgements: Thank you everyone.