Logging an offset line feature

When logging a Line feature, if you are unable to get to it, you can offset your position while tracking the line:

  • horizontally left or right from your current position by up to 100 m

  • vertically, by up to 100 m

For example, you need to accurately collect the position of a stream which is down a one meter bank and you can only get within two meters of the center of the stream. The offset feature enables you to accurately collect the actual position of the stream while walking along the top of the bank, by setting a horizontal offset (to your left or right as appropriate) of 2 meters, and a vertical offset of -1 meter.

To offset your position when logging a Line feature:

  1. Tap Line Offset at the bottom of the screen. The Line Offset dialog opens.

  2. Set your offset to the left or right of your current position, and enter the required horizontal offset distance, up to 100 m.

  3. Enter the required vertical offset height (positive value) or depth (negative value) up to 100 m.

  4. Tap Start Offset Tracking to start the offset.

    The line logging behavior is the same as a regular tracked line, except the line will be offset from your position by the values that you specified.

    To stop tracking your offset line and enable you to keep collecting more positions for your line, tap the back arrow at the bottom left of the screen ; you can then tap any of the collection buttons at the bottom of the screen and continue your line with regular tracking, more offset tracking, a GNSS position, or digitizing — a line can be made up of all different collection methods.

  5. When you have logged the line, tap at the top of the screen; TerraFlex returns to the form.

When setting up a line template in Map Viewer, you are able to configure the tracking as time-based or distance-based logging; see Editing template properties. These settings will apply to a regular tracked line and an offset line.

If you are logging an offset line that is configured as time-based, and if you are stationary at times, TerraFlex has no way of knowing in which direction you will be traveling, so the live view of your line logging will appear to bounce around like an asterisk on the screen and the result can look messy.

This is only temporary on the live view; as soon as you tap the back arrow , the offset will correct itself and get rid of the extra noise (asterisks). When you tap top right of the screen, go back to the form view and then reopen the map view, it will also show the corrected offset. The end result will be much better than what you see in the live view.

You will not see the same noise (astericks) when a line is set to distance-based as it is not trying to collect a position while you are stationary.