RouteFlags is a long ( 32bit unsigned integer or DWORD ) that contains waypoint spacing and other route control 'bits'
When the return of the route is enabled, your subscription will also have a minimum waypoint spacing figure.
When the route is returned it will always have any Routing Point that was used or passed en-route, any waypoint that terminates a Great circle leg and in addition any waypoint inserted into the route by the scanner if used.
This route will give you a general idea of the geographical route used, in order to plot the route on a map you will need to introduce further waypoints this is what waypoint spacing controls. The allowed values are between 1023 and 1.
When your request includes waypoint spacing and this is included in your subscription, the number of waypoints returned will increase. Specifying a waypoint spacing of 10 miles does not mean that the returned route will contain a waypoint every 10 miles, rather any waypoint in the original route that is within 10 miles of another will be returned, intermediate waypoints with a distance of < 10 miles to another will not be returned.
Apart from controlling waypoint spacing RouteFlags also controls the route scanner, values for the various 'bits' are shown in the table below.
Numeric Value |
|
---|---|
1 |
Waypoint Spacing |
2 |
Waypoint Spacing |
4 |
Waypoint Spacing |
8 |
Waypoint Spacing |
16 |
Waypoint Spacing |
32 |
Waypoint Spacing |
64 |
Waypoint Spacing |
128 |
Waypoint Spacing |
256 |
Waypoint Spacing |
|
|
1024 |
Scan route for (S)ECA Zones |
2048 |
Scan route for Loadline Zones |
4096 |
Scan route for Indian Ocean Piracy Zone |
8192 |
Reserved for future use |
16384 |
Reserved for future use |
As an example, assuming we a route with 20 mile spacing of the waypoints and scanned for SECA areas and ECA areas, we would pass a value of 17428 which is 20 + 1024 + 16384