"Sang-Ho Yun" wrote in message <firstname.lastname@example.org>... > I have two groups of polygons (10000 polygons in one group, 1 million polygons in the other group). I want to know which polygons in each group have overlaps with the polygons in the other group. I know "polybool" can be used to take the intersection of overlapping polygons. However, I don't need the shape of the intersection. I only need binary parameter (either 1 for overlap or 0 for no-overlap) for each polygon in each group. > > Any idea?