Configure electronic navigational charts

Display and configure electronic navigational charts per ENC specification.

Use case

The S-52 standard defines how Electronic Navigational Chart (ENC) content should be displayed to ensure that data is presented consistently across every charting system. S-52 defines several display options, including variations on symbology to ensure that charts are readable both at night and in direct sunlight.

How to use the sample

When opened, the sample displays an electronic navigational chart. Tap on the map to select ENC features and view the feature’s acronyms and descriptions shown in a callout. Tap “Display Settings” and use the options to adjust some of the ENC mariner display settings, such as the colors and symbology.

How it works

1. To display ENC content:
   1. On ENCEnvironmentSettings.shared, set resourceURL to the local hydrography data directory and sencDataURL to a temporary directory.
   2. Create an ENCExchangeSet using URLs to the local ENC exchange set files and load it.
   3. Make an ENCCell for each of the ENCExchangeSet.datasets and then make an ENCLayer from each cell.
   4. Add the layers to the map using Map.addOperationalLayers(_:) and create a MapView to display the map.
2. To select ENC features:
   1. Use onSingleTapGesture(perform:) on the map view to get the screen point from the tapped location.
   2. Create a MapViewReader to get the MapViewProxy and use it to identify nearby features to the tapped location with identifyLayers(screenPoint:tolerance:returnPopupsOnly:maximumResultsPerLayer:).
   3. From the resulting IdentifyLayerResult, get the ENCLayer from layerContent and the ENCFeature(s) from geoElements.
   4. Use ENCLayer.select(_:) to select the ENC feature(s).
3. To set ENC display settings:
   1. Get the ENCDisplaySettings instance from ENCEnvironmentSettings.shared.displaySettings.
   2. Use marinerSettings, textGroupVisibilitySettings, and viewingGroupSettings to access the settings instances and set their properties.
   3. Reset the display settings using resetToDefaults() on the settings instances.

Relevant API

• ENCCell
• ENCDataset
• ENCDisplaySettings
• ENCEnvironmentSettings
• ENCExchangeSet
• ENCLayer
• ENCMarinerSettings
• ENCTextGroupVisibilitySettings
• ENCViewingGroupSettings
• IdentifyLayerResult

Offline data

This sample downloads the ENC Exchange Set without updates item from ArcGIS Online automatically.

The latest Hydrography Data can be downloaded from the Esri Developer downloads. The S57DataDictionary.xml file is contained there.

Additional information

Read more about displaying and deploying electronic navigational charts on Esri Developer.

Tags

ENC, hydrography, identify, IHO, layers, maritime, nautical chart, S-52, S-57, select, settings, symbology