Working with Markups > Measurements > ECAD Measurements > ECAD Objects Eligible for Measurement
  
ECAD Objects Eligible for Measurement
Select points on any of these objects as a measurement reference:
Board outline
Component
Geometry associated with a net
Pad
Via
Figure
Region
Hole
Test point
Bend line
You cannot use these objects as measurement references:
Padstack
Rat’s Nest line
Reference designator
Pin number
Markup