[GIS] Split polygon into several smaller polygons in QGIS

polygonqgissplitting

I have a layer of polygons depicting response boundaries, I would like to break each of these polygons into a number of sub-polygons. As this is for an exploratory project, the polygons themselves can be relatively random.

I have tried using Random Points and Voronoi Polygons to create a new mesh of smaller areas, however I need the sub-polygons to fit exactly within their parent polygon for each individual polygon (no sub-polygon should cross 2 parent polygons).

I have looked at Sub-dividing a polygon into smaller polygons, which seems relevant but I couldn't see how it applies, and Splitting large number of polygons at same time into smaller polygons? seems to do pretty much what I want, except my second layer is a polygon layer and the borders of the polygons do not match.

I am using QGIS, but also have access to SAGA GIS if that works better.

Best Answer

Michael's solution above gives the answer

  1. Include additional polygons around the borders of the response boundaries of interest (this is to ensure that all areas of the response boundary are contained within one of the created sub-polygons) (or the bounding box)
  2. Use Vector -> Research Tools -> Random Points for the ResponseBoundaries layer
  3. Vector -> Geometry Tools -> Voronoi Polygons to create a layer of smaller polygons
  4. Vector -> Geoprocessing Tools -> Intersect
Related Question