I am digitising line-features based on WGS-84 point-coordinates from a PDF which cannot be copied from.
The final line layer should contain lines which each connect two points and have the following attributes:
- Name of start point - name of end point
- value in [ft]
- value in [m]
- remark (same for all features)
- date of creation
Currently I have a csv-based point layer which simply contains the name and coordinates of each point.
Creating the point layer is no problem, but creating the lines is a bit of a hassle. Either I manually create a
.csv containing all existing connections between points like the following table and run
connect by lines:
Or I digitise the lines manually but fill in the values (except for the value in [ft]) automatically.
Personally I would prefer option 2, since option 1 involves more manual work and the process has to be repeated regularly (and I figure I could transfer the solution to other tasks), but I can't get the expression right which should fill in the name of the line. All other values are created flawlessly (though they are not taken from another layer based on geometry).
I added the WKT of each point to the point-layer. Currently I am running the following, which returns
NULL, despite it seems to be correct to me:
attribute(get_feature('point-layer','geom',geom_to_wkt(start_point($geometry))),'Waypoint')||' - '||attribute(get_feature('point-layer','geom',geom_to_wkt(end_point($geometry))),'Waypoint')
Any ideas where I went wrong?