This structure contains all the parameters of the duct size calculator. The duct size calculator uses this structure
to pass information to and receive information from the duct size calculator plugin.
The duct size calculator plugin uses the UF_ROUTE_duct_parameter_types_e to know which parameter is being sent from the dialog.
The plugin calculates the required values and updates this structure.
Use the UF_ROUTE_duct_parameters_m macro to initialize this structure.