The Polyline tool is used to measure the distance or perimeter of a region of interest:
- select Polyline tool in the Measure menu.
- position the mouse pointer on the point from which you want to start measuring, click and release the selected mouse button.
- then move the cursor to the second, third, fourth, etc. points and each time click the selected mouse button once and release it.
- when the cursor is moved to the last point, double click the selected mouse button, and the total length of all the lines is displayed. If you place the last point on top of the first point, you will get the perimeter:
Figure 69. Perimeter measurement