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   Transform a 3D data structure. r is optional.
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   Form:
   g = Trans3DMF( m, g, r )
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   ------
   Inputs
   ------
   m           (3,3) Transformation matrix.
   g           (1,1) Data structure
                     .m    (:)   Data structure for meshes
                                 .v                  (:,3) Vertices
                                 .f                  (:,:) Faces
                                 .ambientCoefficient (1,1) 
                                 .diffuseColor       (3,1)
                                 .specularColor      (3,1)
                                 .specularControl    (1,1)
                                 .transparencyColor  (3,1)
                     .name (1,:) Name
   r           (3,1) Position vector

   -------
   Outputs
   -------
   g           (1,1) Transformed data structure

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