[Groff] grn independent from device

[Werner LEMBERG]

Daniel,


while adapting grn to the groff layout, I've detected that grn is
dependent on the device's resolution to set the line thickness.

Two questions:

  . Is it possible to make grn independent from the output device,
    similar to pic?

  . If not, why is `256' the lower limit to make the default line
    thickness values dependent on the resolution (this behaviour is
    not documented, BTW)?


      Werner