/contrib/groff/src/preproc/grn/README

 1This is grn from the Berkeley ditroff distribution.  It has no
 2AT&T code and is therefore freely distributable.
 3
 4Tim Theisen <tim@cs.wisc.edu>
 5
 6=====================================================================
 7
 8This is the modified code for the groff.  It uses the different
 9devxxx format that is ascii rather than binary as in the
10Berkeley distribution.  Since groff does not have the \Ds option
11for line drawing (dotted, dashed, etc.), this version includes
12the routines for drawing curves and arcs, so it does not use the
13\D~, \Da nor \Dc.  Although also included in here is a routine
14for drawing the optional gremlin style curves, it is not used
15because the gremlin editor uses the conventional spline
16algorithm.  The Berkeley grn has the choice of different
17stipples.  Here, only different shades of gray will be painted
18depending on the gremlin file.  It is possible to upgrade this at
19a later time.  (Daniel Senderowicz <daniel@synchrods.com> 12/28/99)
20
21=====================================================================
22
23Gremlin produces three types of curves: B-Splines, interpolated
24curves and Bezier.  As the original Berkeley grn, now groff grn
25will honor B-Splines and interpolated curves.  Bezier curves will
26be printed as B-Splines.  (Daniel Senderowicz <daniel@synchrods.com>
2710/04/02)
28
29=====================================================================
30
31It has been further modified by Werner Lemberg <wl@gnu.org> to fit
32better into the groff package.
33
34  . Replaced Makefile with Makefile.sub.
35
36  . Removed dev.h since it is unused.
37
38  . Renamed grn.1 to grn.man; this man page has been extensively
39    revised.
40
41  . Used error() and fatal() from libgroff for all source files.
42
43  . Renamed *.c to *.cpp; updates as needed for C++ (prototypes, proper
44    casts, standard header files etc).  Heavy formatting.
45
46  . main.cpp:
47
48      Using groff's default values instead of DEVDIR, DEFAULTDEV, PRINTER,
49      TYPESETTER, and GREMLIB.
50
51      `res' is now an integer.
52
53      Added `-C' command flag (for compatibility mode) as with other
54      preprocessors.
55
56      Added `-F' and `-v' option (similar to troff).
57
58      Renamed `-L' option to `-M' for consistence.
59
60      Removed `-P' option.
61
62      Using font::load_desc() for scanning DESC files.
63
64      Removed SYSV-specific code.
65
66      Using macro_path.open_file() for getting gremlin graphic files.
67
68      Added usage().