Structure UF_CGM_size_t specifies the size of geometry recorded
in the CGM file. The size field of the UF_CGM_export_options_t
structure is a structure of type UF_CGM_size_t.

If the mode field of the UF_CGM_size_t structure is set to
UF_CGM_SIZE_BY_SCALE, then geometry is sized according to the
scale factor specified by the scale field. If the mode field is
set to UF_CGM_SIZE_BY_DIMENSIONS, then geometry is sized to fit
the dimensions specified by the dimensions field.