I just spent twenty minutes to add measurements to a 3D print model that I had downloaded, and only once finished did I realize that the anchors of the measurements were at different z-depth (I was looking at the x-y plane).
Which made me wonder, is there any way of restricting measurements to place the second point of a measurement line at the same depth as the first point of the measurement line?
I don’t know if there is a separate function. 
Or try Quad view
hotkey: Ctrl+Alt+Q (To quit, use the shortcut key again)
You are talking of using the Measure feature form the tool bar ??
I would use this for a imple measure only and thsi for further use of the measures: MeasuteIt addon…
( this is maybe a bit too late 
)
Thanks! I still think it would be a nice addition to have the option to constrain the standard measurement to be parallel to the viewport.
