If a few points,
no worries to do it "with basic functions" integrated into Solidworks.
Moreover, if you only want X-Y, no Z, it simplifies the work by 33%!!
In the 3D concerned, PRT or ASM, you must therefore open the file.
Compared to "where" the origin of the part is located, it is necessary to estimate a calculation delta that will work in any case.
For example, if your set has geometries of the order of 500 mm, if we take a calculation-delta of 2000, 3000, or 5000 mm, we should be quiet.
So following this Delta, we create basic planes according to the Axes we want to measure shift to the "negative" of the Delta value. We can rename these planes P.Calcul.Delta-X Y or Z (if we respect the filter principles, we hide them in the tree because it is only used for construction...).
Then, at the end of the piece, we create a 3d sketch, or 2d if we want to measure that following 2 axes...
In this sketch, we place a point in the void, we fix the point. Then we dimension this point according to P.Calcul.Delta-X, Y or Z (this should pose piloted dimensions).
We rename each side (if we want): Point-1-X-side / Point-1-Y-side / Point-1-Z-side
We leave the sketch, and we rename the sketch: E.Calcul.Point (for example)
We hide the sketch because it's construction...
We go to Tools / Equation.
We create the global variables: Point-1-X / Point-1-Y / Point-1-Z
in each variable we put "= Point-1-X-cote@E.Calculus.Point - D1@P. Calculus.Delta-X"
We go to the properties of the file, as we put calculated values, as a reminder we always place them "at the config" (example of other calculated values: Mass, Volume, Density, Area, etc...).
We add a new property: Point-1-X-Value
and we make it point to the corresponding global variable...
do the same for the Y, then Z.
Then we leave the properties.
We re-edit the 3D sketch, we de-fix the point, and we add a coincident with the geometry we want to measure...
Then we leave the sketch, we do a little Ctrl+B
(reminder we have to stop doing only Ctrl+Q at all times "it's not rebuilding"!! )
And then, looking at the properties, we must find the values of the point, even with negative values if this is the case!!
redo the procedure to add more measurement points...
May the dark side be with you all...