Re: [Groff] inconsistencies with color specification

[Gaius Mulley]

> I propose to require both commands m and DF to have 3 arguments each of
> which can arbitrarily be specified as a float or a hex number in C style.
> This could be naturally done by calling the parser's get_string() function
> thrice.  Moreover there are standard C library functions to handle the
> transformation.

yes I think this would be cleaner. Maybe it would be simpler for the ditroff
color commands m and DF to standardise on using 4 byte hex numbers for each
color component. This way we can remove the need to read in floating point
values and 2 byte hex strings in input.cc.

Minor note: I wonder whether we should be using cmyk as the interface between
troff and its devices, rather than the rgb scheme?

Gaius