Skill code to find floating vias

You can use dbGetTrueOverlaps to find metal shapes that overlap each of your vias. This could be a very time consuming process if you are dealing with a large cell with lots of vias.

If you are using 6.1.x, you can get your vias this way:
vias = setof(x geGetEditCellView()~>vias x~>viaHeader~>viaDefName == "myvia1")

If you are using 5.1.41, you can get your vias using something like this (the example below would also need to be tweaked to tread the vias as instances instead of vias):
vias = setof(x geGetEditCellView()~>instances x~>cellName == "myvia1")

If your vias are between metal1 and metal2, then you'll want to see first if metal1 overlaps the via and then if metal2 overlaps the via. To be most accurate, you'll need to get the dimensions of the metal inside the via before you check for overlaps. To keep this post simple, I'll show you the command if you simply check if the bounding box of the via overlaps the metal.

procedure(floatingVias(@optional (cv geGetEditCellView()))
  let((vias m1Overlaps m2Overlaps)
    vias = setof(x cv~>vias x~>viaHeader~>viaDefName == "VIA1_STD")

    foreach(via vias
      m1Overlaps = dbGetTrueOverlaps(cv via~>bBox list("metal1" "drawing") 0:20)
      m1Overlaps = setof(x m1Overlaps !listp(x) || (listp(x) && car(x)~>objType!="stdVia"))
      m2Overlaps = dbGetTrueOverlaps(cv via~>bBox list("metal2" "drawing") 0:20)
      m2Overlaps = setof(x m2Overlaps !listp(x) || (listp(x) && car(x)~>objType!="stdVia"))
      cond(
        (!m1Overlaps && !m2Overlaps  printf("Floating via at %L\n" via~>xy))
        (!m1Overlaps  printf("via not covered by metal1 at %L\n" via~>xy))
        (!m2Overlaps  printf("via not covered by metal2 at %L\n" via~>xy))
      )
    )
  ) ;let
) ;proc

Obviously, this is not very flexible as it is written (it assumes version 6.1). It could be improved by checking to see what layers are used in the via and check for overlaps on those layers. Notice that the results of dbGetTrueOverlaps need to be filtered to remove the metal in the vias themselves. Also, if your metal shapes for metal1 and metal2 are very different, you'll not want to use the bBox if the instance, but rather the bounding box of the actual metal in the vias transformed to the top level coordinates. The dbGetTrueOverlaps will return shapes that abut the given bBox, so they do not have to overlap.

Derek