Some users of the 3D versions were storing 2D data in it. Using a 3D tree for 2D data adds a spatially redundant branch every 3rd level, as well as some extra memory use, best avoid this.
Some users of the 3D versions were storing 2D data in it. Using a 3D tree for 2D data adds a spatially redundant branch every 3rd level, as well as some extra memory use, best avoid this.