vb2cub

From VoxBoWiki

vb2cub will convert any 3D file in a supported format to CUB format. It's superceded by vbconv, but maintained for the benefit of old-timers. Here's the help:

VoxBo vb2cub (v1.8.5pre8/May  6 2010)
usage:
  vb2cub  [<flags>] <3D file/dir> <cubname>
flags:
  -f             convert to floating point
  -n             replace NaNs and Infs with zeros
  -h             show help
  -v             show version