S-421 is a route plan product specification used to describe a ship's planned route and its related route elements. S-421 data can record the spatial location, waypoints, route segments, and related attributes of a planned route, providing standardized data for route planning, navigation management, and maritime data exchange.

S-421 data is stored in *.gml files that comply with the product specification. SuperMap iDesktopX supports managing S-421 route plan data, including importing *.gml data that complies with the S-421 product specification, and performing symbolic display on S-421 data based on the matched feature catalogue and portrayal catalogue specification.

S-421 route plan data is applicable to the following scenarios:

• Route planning: View and manage ship planned routes to provide spatial data support for voyage plan compilation.
• Navigation management: Browse planned routes and related route elements on the map to assist in route verification during navigation.
• Maritime data exchange: Use GML data that complies with the S-421 product specification for planned route information exchange and sharing.

This chapter introduces the following contents:

• Importing S-421 Data: Describes how to import *.gml files that comply with the S-421 product specification and add the data to a map for browsing.
• S-421 Data Display: Describes how to perform symbolic display on route plan data.