How to find if a coordinate is on a net

 You could always turn the point into a small bbox and use dbGetTrueOverlaps to see what nets are under it. Or, if you want the most accurate method, you can do something like this:

cv=geGetEditCellView()
foreach(net cv~>nets
    foreach(fig net~>figs
     if( absIsPointInsideFig(fig pt ) then 
       foundNet = net~>name
     );if
    );foreach
   );foreach
foundNet ;name of net under point

Another simple approach is to use gePointQuery. This is similar to geSingleSelectPt except that it doesn't do the selection. The routine takes three arguments: window id, coordinate and filter function.

result=gePointQuery(hiGetCurrentWindow() 10:20 "myFilter")

procedure(myFilter(fig)
    if(fig~>layerName=="metal1" && fig~>objType=="path"
        t
        nil
    )
)

Derek