4.4BSD/usr/share/man/cat5/groff_out.0
GROFF_OUT(@MAN5EXT@) BSD Reference Manual GROFF_OUT(@MAN5EXT@)
NNAAMMEE
groff_out - groff intermediate output format
DDEESSCCRRIIPPTTIIOONN
This manual page describes the format output by GNU troff.
The output format used by GNU troff is very similar to
that used by Unix device-independent troff. Only the dif-
ferences are documented here.
The argument to the ss command is in scaled points (units
of _p_o_i_n_t_s_/n_, where _n is the argument to the ssiizzeessccaallee com-
mand in the DESC file.) The argument to the xx HHeeiigghhtt
command is also in scaled points.
The first three output commands are guaranteed to be:
xx TT _d_e_v_i_c_e
xx rreess _n _h _v
xx iinniitt
If the ttccoommmmaanndd line is present in the DESC file, troff
will use the following two commands
tt_x_x_x _x_x_x is any sequence of characters terminated by a
space or a newline; the first character should be
printed at the current position, the the current
horizontal position should be increased by the
width of the first character, and so on for each
character. The width of the character is that
given in the font file, appropriately scaled for
the current point size, and rounded so that it is a
multiple of the horizontal resolution. Special
characters cannot be printed using this command.
uu_n _x_x_x This is same as the tt command except that after
printing each character, the current horizontal
position is increased by the sum of the width of
that character and _n.
Note that single characters can have the eighth bit set,
as can the names of fonts and special characters.
The names of characters and fonts an be of arbitrary
length; drivers should not assume that they will be only
two characters long.
When a character is to be printed, that character will
always be in the current font. Unlike device-independent
troff, it is not necessary for drivers to search special
fonts to find a character.
Groff Version @VERSION@ @MDATE@ 1
GROFF_OUT(@MAN5EXT@) BSD Reference Manual GROFF_OUT(@MAN5EXT@)
The DD drawing command has been extended. These extensions
will only be used by GNU pic if the --xx option is given.
DDff _n\n Set the shade of gray to be used for filling solid
objects to _n; _n must be an integer between 0 and
1000, where 0 corresponds solid white and 1000 to
solid black, and values in between correspond to
intermediate shades of gray. This applies only to
solid circles, solid ellipses and solid polygons.
By default, a level of 1000 will be used. Whatever
color a solid object has, it should completely
obscure everything beneath it. A value greater
than 1000 or less than 0 can also be used: this
means fill with the shade of gray that is currently
being used for lines and text. Normally this will
be black, but some drivers may provide a way of
changing this.
DDCC _d\n Draw a solid circle with a diameter of _d with the
leftmost point at the current position.
DDEE _d_x _d_y\n
Draw a solid ellipse with a horizontal diameter of
_d_x and a vertical diameter of _d_y with the leftmost
point at the current position. delim $$
DDpp $dx sub 1$ $dy sub 1$ $dx sub 2$ $dy sub 2$ $...$ $dx
sub n$ $dy sub n$\n
Draw a polygon with, for $i = 1 ,..., n+1$, the _i-
th vertex at the current position $+ sum from j=1
to i-1 ( dx sub j , dy sub j )$. At the moment,
GNU pic only uses this command to generate trian-
gles and rectangles.
DDPP $dx sub 1$ $dy sub 1$ $dx sub 2$ $dy sub 2$ $...$ $dx
sub n$ $dy sub n$\n
Like DDpp but draw a solid rather than outlined poly-
gon.
DDtt _n\n Set the current line thickness to _n machine units.
Traditionally Unix troff drivers use a line thick-
ness proportional to the current point size;
drivers should continue to do this if no DDtt command
has been given, or if a DDtt command has been given
with a negative value of _n. A zero value of _n
selects the smallest available line thickness.
A difficulty arises in how the current position should be
changed after the execution of these commands. This is
not of great importance since the code generated by GNU
pic does not depend on this. Given a drawing command of
Groff Version @VERSION@ @MDATE@ 2
GROFF_OUT(@MAN5EXT@) BSD Reference Manual GROFF_OUT(@MAN5EXT@)
the form
\\DD''_c $x sub 1$ $y sub 1$ $x sub 2$ $y sub 2$ $...$
$x sub n$ $y sub n$'
where _c is not one of cc, ee, ll, aa or ~~, Unix troff will
treat each of the $x sub i$ as a horizontal quantity, and
each of the $y sub i$ as a vertical quantity and will
assume that the width of the drawn object is $sum from i=1
to n x sub i$, and that the height is $sum from i=1 to n y
sub i$. (The assumption about the height can be seen by
examining the sstt and ssbb registers after using such a DD
command in a \w escape sequence.) This rule also holds
for all the original drawing commands with the exception
of DDee. For the sake of compatibility GNU troff also fol-
lows this rule, even though it produces an ugly result in
the case of the DDff, DDtt, and, to a lesser extent, DDEE com-
mands. Thus after executing a DD command of the form
DD_c $x sub 1$ $y sub 1$ $x sub 2$ $y sub 2$ $...$ $x
sub n$ $y sub n$\n
the current position should be increased by $( sum from
i=1 to n x sub i , sum from i=1 to n y sub i )$.
There is a continuation convention which permits the argu-
ment to the xx XX command to contain newlines: when out-
putting the argument to the xx XX command, GNU troff will
follow each newline in the argument with a ++ character (as
usual, it will terminate the entire argument with a new-
line); thus if the line after the line containing the xx XX
command starts with ++, then the newline ending the line
containing the xx XX command should be treated as part of
the argument to the xx XX command, the ++ should be ignored,
and the part of the line following the ++ should be treated
like the part of the line following the xx XX command.
SSEEEE AALLSSOO
ggrrooffff__ffoonntt(@MAN5EXT@)
Groff Version @VERSION@ @MDATE@ 3