xref: /freebsd-10.0-release/contrib/groff/src/preproc/grn/README

This is grn from the Berkeley ditroff distribution.  It has no
AT&T code and is therefore freely distributable.

Tim Theisen <tim@cs.wisc.edu>

=====================================================================

This is the modified code for the groff.  It uses the different
devxxx format that is ascii rather than binary as in the
Berkeley distribution.  Since groff does not have the \Ds option
for line drawing (dotted, dashed, etc.), this version includes
the routines for drawing curves and arcs, so it does not use the
\D~, \Da nor \Dc.  Although also included in here is a routine
for drawing the optional gremlin style curves, it is not used
because the gremlin editor uses the conventional spline
algorithm.  The Berkeley grn has the choice of different
stipples.  Here, only different shades of gray will be painted
depending on the gremlin file.  It is possible to upgrade this at
a later time.  (Daniel Senderowicz <daniel@synchrods.com> 12/28/99)

=====================================================================

Gremlin produces three types of curves: B-Splines, interpolated
curves and Bezier.  As the original Berkeley grn, now groff grn
will honor B-Splines and interpolated curves.  Bezier curves will
be printed as B-Splines.  (Daniel Senderowicz <daniel@synchrods.com>
10/04/02)

=====================================================================

It has been further modified by Werner Lemberg <wl@gnu.org> to fit
better into the groff package.

  . Replaced Makefile with Makefile.sub.

  . Removed dev.h since it is unused.

  . Renamed grn.1 to grn.man; this man page has been extensively
    revised.

  . Used error() and fatal() from libgroff for all source files.

  . Renamed *.c to *.cpp; updates as needed for C++ (prototypes, proper
    casts, standard header files etc).  Heavy formatting.

  . main.cpp:

      Using groff's default values instead of DEVDIR, DEFAULTDEV, PRINTER,
      TYPESETTER, and GREMLIB.

      `res' is now an integer.

      Added `-C' command flag (for compatibility mode) as with other
      preprocessors.

      Added `-F' and `-v' option (similar to troff).

      Renamed `-L' option to `-M' for consistence.

      Removed `-P' option.

      Using font::load_desc() for scanning DESC files.

      Removed SYSV-specific code.

      Using macro_path.open_file() for getting gremlin graphic files.

      Added usage().