Measure

Measure distances

Click on the Measure distance() tool. Draw a line, it's length will be displayed in the top left corner of the map. Double click to end the measurement.

You can snap to other vector layers vertices if their layer has Information() checkbox checked in the Layers settings and Snap checkbox checked in the Main menu - System - Settings.

You zoom by using the Navigation bar and move by clicking and holding the map while measuring.

To get an accurate result the geometry is reprojected to WGS84 using proj4js and Vincenty inverse formula is used to calculate the distance.

Measure areas

Click on the Measure area() tool. Draw a polygon, it's area will be displayed in the top left corner of the map. Double click to end the measuremnt.

You can snap to other vector layers vertices if their layer has Information() checkbox checked in the Layers settings and Snap checkbox checked in the Main menu - System - Settings.

You zoom by using the Navigation bar and move by clicking and holding the map while measuring.

To get an accurate result the geometry is reprojected to WGS84 using proj4js and Robert. G. Chamberlain and William H. Duquette, "Some Algorithms for Polygons on a Sphere", JPL Publication 07-03, Jet Propulsion Laboratory, Pasadena, CA, June 2007 is used to calculate the distance.