ARINC 661 client API: Setting the Map reference

To set the A661_MAPHORZ widget reference coordinates^[1]

or widgets#A661_MAPVERT widget reference

, you can:

• Set the A661_MAPHORZ widget PRP coordinates (or the the A661_MAPHORZ widget screen PRP position)^[2]
  The (Latitude, Longitude) coordinates must be defined in degrees
• Set the A661_MAPHORZ widget range (or the the A661_MAPHORZ widget screen range)
• Set the A661_MAPHORZ widget orientation relative to true North^[3]
  The orientation must be defined in degrees

The projection algorithm use the following characteristics:

• The reference position of the Map (the PRP), both on the real world in (Latitude, Longitude)^[4]
  The (Latitude, Longitude) coordinates must be defined in degrees
  , but also in screen coordinates in the reference system of the MapHorz widget
• The range of the Map, both on the real world in nautical Miles, but also in screen coordinates
• The North orientation of the Map^[5]
  The orientation must be defined in degrees

A661_MAPHORZ properties to set

The properties which can be set are the following:

• The PRP to specify the reference of the Map
• The range to specify the range of the Map
• The orientation to specify the orientation of the Map relative to true North

Note that it is not mandatory to have the PRP at the center of the A661_MAPHORZ widget. For example, the following configuration is valid:

Specify the PRP

There are two types of coordinates for the PRP:

• The PRP screen coordinates relative to the reference of the A661_MAPHORZ, defined in 1/100 of mm:

              // set the X coordinate of the PRP
              api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_PRP_SCREEN_X, prpScreenXPosition);
              // set the Y coordinate of the PRP            
              api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_PRP_SCREEN_Y, prpScreenYPosition);
  

• The PRP latitude and longitude coordinates:

              // set the latitude of the PRP
              api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_PRP_X, prpLatitude);
              // set the longitude of the PRP            
              api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_PRP_Y, prpLongitude);
  

Specify the range

It is possible to set the range in Nautical Miles, or the range in screen coordinates:

      // set the range in Nautical Miles
      api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_RANGE, rangeNM);
      // set the range in Screen coordinates        
      api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_SCREEN_RANGE, rangeScreen);

Specify the orientation

It is possible to set the orientation of the map relative to true North:

           api.setWidgetParameter(appliId, layerId, MapHorzId, ARINC661.A661_ORIENTATION, orientation);