Import photo of a plan

Imports a photo of a paper plan as an underlay. The photo is straightened on the four corners of the sheet, so you can trace it like a scan.

How it works

Choose the layer under "New underlay on layer". Then type UP or click "Import photo of a plan", and pick a photo. A tablet may offer its camera as well.
In "Straighten the photo", check the four proposed corners. If no sheet was found, drag them onto the corners of the sheet. While you drag a corner, an enlarged view at the side of the photo shows exactly where it lies.
Under "Shape of the sheet" keep "A sheet (A4, A3, A2 …)", or choose "Other: estimate from the photo". Then click "Straighten and import". What lies outside the corners is cut off.
The picture is stored and "Fit underlay" starts: click both ends of a distance you know and type its real length in mm, so the underlay gets its scale.