Doodlez
This solution is based on wrangles but it deals with the same problem (Add point to group was available as a point wrangle function, it doesn't work in the attrib wrangle)
setpointgroup still works fine.
Doodlez
This solution is based on wrangles but it deals with the same problem (Add point to group was available as a point wrangle function, it doesn't work in the attrib wrangle)
Points per Area
To determine proximity, points are seeded on the surface of all the objects. There must be enough points for close points to occur to detect close surfaces. This should be scaled down by the square of the geometry size. If your geometry is 10x bigger, you want 1/100 the points per area.