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Geometry Types

Define locations and shapes

A key feature of Alloy is the ability to visualise your assets on the map. Therefore, all items have a standard Geometry attribute that can be populated with coordinate data to represent an item's location and shape. To learn how, see Editing item geometry.

Several types of geometry data can potentially be stored, ranging from a single point to complex polygons. An item's design defines which of these types are allowed to be set. By default, all geometry types are allowed on designs you create. To limit a design to one or more geometry types (or none at all), see Editing general design details.

Note

You can add extra Geometry attributes to a design/interface.

Geometry types

Basemap alignment

In Alloy, all geometry is saved using the WGS84 Lat/Lng (EPSG:4326) coordinate system.

If the active basemap uses another coordinate system, item geometry is transformed on the fly (by Alloy or the map server) to keep things in proportion. Occasionally, this can result in the geometry appearing slightly misaligned with the basemap.

Therefore, we recommend switching to the most relevant basemap before editing item geometry, so you can draw directly over the basemap's features if necessary.