I'm working in QGIS 2.18 but I can work with QGIS 3 or ArcMap 10.2.

I have a multipoint layer providing from a lasDataset where I've isolated the buildings.

I want to create a polygon layer where every building or group of buildings are individual polygons. The problem is I can't use any attribute to group them because I don't have any. Concave Hull only creates one polygon. So I have to group them by other way. by distance? How can I do it?

The points I have The points I have

How I want to group them How I want to group them

  • Do the points have any attributes which define the groups? – TeddyTedTed Jun 19 at 12:43
  • 1
    I suggest you to look at DBSCAN clustering tool in QGIS 3. It produces CLUSTER_ID attribute. – Kadir Şahbaz Jun 19 at 12:57
  • I can't use any attribute to group them because I don't have any. – Francesc Cañas Soler Jun 19 at 14:11

A super simple solution: buffer your points by your desired distance, with a dissolve. Then, inward buffer by that same distance (use a negative distance value). Since the initial buffers were dissolved, the area between points will not be removed by inward buffering and will create those polygons for you.


Here is a solution but only if you have the original LAS file, so it works for me. But I'll be happy to know if there is other way to proceed if you have the multipoint shape.


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