As of PDAL v2.6.0, the density command is marked as DEPRECATED. It will be removed from the default install in PDAL v2.7 and removed completely in PDAL v2.8.

The density command produces a tessellated hexagonal OGR layer from the output of filters.hexbin.

$ pdal density <input> <output>
--input, -i        Input point cloud file name
--output, -o       Output vector data source
--lyr_name         OGR layer name to write into datasource
--ogrdriver, -f    OGR driver name to use
--sample_size      Sample size for automatic edge length calculation. [5000]
--threshold        Required cell density [15]
                   Tolerance area to apply to holes before cull
--smooth           Smooth boundary output