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Line geometry

Define a line of connected points​

This geometry type defines multiple points that form a single line. Use it to describe linear assets, e.g. streets, fences, railways.

An item with line geometry displayed on the map

How to draw​

When editing item geometry (or any other geometry field in Alloy), the Geometry Editor appears. The row of draw tools indicates which geometry types are allowed by the item's design (or the source of the field).

The draw tools are dimmed out if the relevant geometry type isn't allowed

Select the Line tool and then select a starting point on the map. Continue selecting points along your desired line. If you need to track a fine curve, select as many points as possible along it! To finish drawing, double-select the final point.

Demonstrating the Line tool in the Geometry Editor

Once a line is finished, the Line tool becomes dimmed to indicate that no further lines can be added.

To edit the line, select an existing point (your mouse will snap to it) and drag it to a different position. To add a new point, select and hold anywhere along the line, and then drag the new point into position! Use the Erase tool to remove points as needed.

Select Done to save your changes.

Editing the points of a line in the Geometry Editor

Example GeoJSON​

To access the underlying code of the current geometry, select Menu in the Geometry Editor and choose GeoJson view.

{
  "type": "LineString",
  "coordinates": [
    [-1.553519, 52.29129],
    [-1.553463, 52.29119],
    [-1.553377, 52.291166],
    [-1.553172, 52.290961],
    [-1.552731, 52.29109]
  ]
}