Measuring border segment length while creating a polygon in QGIS

Question

I am recreating historic (1770s) land parcels for an area of a town based on their description in written deeds. This will be a series of intersecting polygons when I am finished, with many sharing borders of other adjacent polygons.

From the written deeds, I know a precise length of each segment of the boundary of the property. For example: "East along the street 140 feet, west along Smith's land 200 feet, south along a river 20 feet" etc. I would like to be able to know how long my polygon border segment is that I am extending from my previous verticy before I create a new verticy, given that I already know how long it should be.

I turned on advanced digitizing and was only able to see the latitude and longitude as I moved around the map.

I used the measure tool, which allows me to see and mark line segments at the appropriate length, but when I click to over to begin making a polygon, the measure tool marks go away. If I could use those as snap vertices or see the measurements still when I create the polygon that would work.

My current option appears to be to pre-measure each segment and "remember" where the vertices were as I draw the polygon. Is there a better option?

Answer 1

Option 1: try this solution where you can set the length of the line first then click on the map and find the angle. You can also change the snapping properties to common angles such as 45/90/180 etc.

Option 2: try the same method but instead of setting the distance first you click on the map first and can see the length of the line in real time. You can also change the snapping properties to common angles such as 45/90/180 etc.

Answer 2

Another option would be to use the QAD plugin,

You can just create the polygon then extend the vertices at a desired length. It works perfectly for the purpose of creating segments at a predefined length.