Hi, Neuro-
You would first have to convert the coords to indices; the program to do that is:
Surf2VolCoord -i std.60.lh.pial.gii -i std.60.rh.pial.gii -sv MNI152_2009_SurfVol.nii -qual LR -closest_nodes XYZ.1D
where XYZ.1D is:
-38 -29 54
-2 -20 60
.... which is assumed to be in DICOM (=RAI) coordinates. The output of that command is:
11496R 1.730468
16730R 1.010598
which tells you the index node number (e.g., "11496"), the letter of which surface it was ("R" here means the second surface, because it was the second letter of the "-qual ..." argument), and the distance between my entered XYZ coordinate and the given index.
Then, you can put the node indices of interest into a text file in two columns, calling it say "nodelist.1D":
11496 16730
and then calculate the distance between the points:
SurfDist -i std.60.rh.pial.gii -input nodelist.1D -Euclidian
... which produced thef ollowing output:
#Internodal euclidian distance for surface std.60.rh.pial.gii
#A distance of -1 indicates an error of sorts.
#From to eDist.
11496 16730 37.23
--pt