Lines, when placed, will give you two set of values to work with: Lengths and Walls. These values are calculated based on the set scale for the page in the PDF and use the height property to calculate the wall surface for each part of the line set.
You can keep placing points along the line until you’ve measured everything you need and end it via either right-clicking or double-clicking.
You can press and hold shift while placing lines to lock them in 45-degree angles from the previous
Change and Adjust
To adjust your measured area you can easily drag the small squares. You can add or delete points on your area by using hotkeys
ALT + Click to add
ALT + SHIFT + click to delete