Get the number of tracks per voxels around the windmills

windmill_voxel(
  local,
  max_distance = 200,
  voxel_size = rep(max_distance/5, 3),
  voxel_box = matrix(c(-10, -10, 0, 10, 10, 20), nrow = 3)
)

Arguments

local: the connection to the local database
max_distance: Use all equal time tracks where the minimum distance in meters between the track and the centre is smaller than max_distance.
voxel_size: Size in meters of the voxel.
voxel_box: Defines the area around the centre for to set of voxels to use. Defined using the index number of the voxels. Defaults to 10 voxels on both side of the centre in x and y and 20 voxels above 0 in the z direction.