драйвер вывода groff для PostScript (groff output driver for PostScript)
Использование (Usage)
The input to grops
must be in the format output by troff(1).
This is described in groff_out(5).
In addition, the device and font description files for the device
used must meet certain requirements: The resolution must be an
integer multiple of 72 times the sizescale
. The ps
device uses a
resolution of 72000 and a sizescale of 1000.
The device description file must contain a valid paper size; see
groff_font(5) for more information.
Each font description file must contain a command
internalname
psname
which says that the PostScript name of the font is psname. It
may also contain a command
encoding
enc_file
which says that the PostScript font should be reencoded using the
encoding described in enc_file; this file should consist of a
sequence of lines of the form:
pschar code
where pschar is the PostScript name of the character, and code is
its position in the encoding expressed as a decimal integer;
valid values are in the range 0 to 255. Lines starting with #
and blank lines are ignored. The code for each character given
in the font file must correspond to the code for the character in
encoding file, or to the code in the default encoding for the
font if the PostScript font is not to be reencoded. This code
can be used with the \N
escape sequence in troff
to select the
character, even if the character does not have a groff name.
Every character in the font file must exist in the PostScript
font, and the widths given in the font file must match the widths
used in the PostScript font. grops
assumes that a character with
a groff name of space
is blank (makes no marks on the page); it
can make use of such a character to generate more efficient and
compact PostScript output.
Note that grops
is able to display all glyphs in a PostScript
font, not only 256. enc_file (or the default encoding if no
encoding file specified) just defines the order of glyphs for the
first 256 characters; all other glyphs are accessed with
additional encoding vectors which grops
produces on the fly.
grops
can automatically include the downloadable fonts necessary
to print the document. Such fonts must be in PFA format. Use
pfbtops(1) to convert a Type 1 font in PFB format. Any
downloadable fonts which should, when required, be included by
grops
must be listed in the file /usr/local/share/groff/1.23.0/
font/devps/download; this should consist of lines of the form
font filename
where font is the PostScript name of the font, and filename is
the name of the file containing the font; lines beginning with #
and blank lines are ignored; fields may be separated by tabs or
spaces; filename is searched for using the same mechanism that is
used for groff font metric files. The download file itself is
also searched for using this mechanism; currently, only the first
found file in the font path is used.
If the file containing a downloadable font or imported document
conforms to the Adobe Document Structuring Conventions, then
grops
interprets any comments in the files sufficiently to ensure
that its own output is conforming. It also supplies any needed
font resources that are listed in the download file as well as
any needed file resources. It is also able to handle inter-
resource dependencies. For example, suppose that you have a
downloadable font called Garamond, and also a downloadable font
called Garamond-Outline which depends on Garamond (typically it
would be defined to copy Garamond's font dictionary, and change
the PaintType), then it is necessary for Garamond to appear
before Garamond-Outline in the PostScript document. grops
handles this automatically provided that the downloadable font
file for Garamond-Outline indicates its dependence on Garamond by
means of the Document Structuring Conventions, for example by
beginning with the following lines
%!PS-Adobe-3.0 Resource-Font
%%DocumentNeededResources: font Garamond
%%EndComments
%%IncludeResource: font Garamond
In this case both Garamond and Garamond-Outline would need to be
listed in the download file. A downloadable font should not
include its own name in a %%DocumentSuppliedResources
comment.
grops
does not interpret %%DocumentFonts
comments. The
%%DocumentNeededResources
, %%DocumentSuppliedResources
,
%%IncludeResource
, %%BeginResource
, and %%EndResource
comments
(or possibly the old %%DocumentNeededFonts
, %%DocumentSupplied‐
Fonts
, %%IncludeFont
, %%BeginFont
, and %%EndFont
comments) should
be used.
In the default setup there are styles called R
, I
, B
, and BI
mounted at font positions 1 to 4. The fonts are grouped into
families A
, BM
, C
, H
, HN
, N
, P
, and T
having members in each of
these styles:
AR
AvantGarde-Book
AI
AvantGarde-BookOblique
AB
AvantGarde-Demi
ABI
AvantGarde-DemiOblique
BMR
Bookman-Light
BMI
Bookman-LightItalic
BMB
Bookman-Demi
BMBI
Bookman-DemiItalic
CR
Courier
CI
Courier-Oblique
CB
Courier-Bold
CBI
Courier-BoldOblique
HR
Helvetica
HI
Helvetica-Oblique
HB
Helvetica-Bold
HBI
Helvetica-BoldOblique
HNR
Helvetica-Narrow
HNI
Helvetica-Narrow-Oblique
HNB
Helvetica-Narrow-Bold
HNBI
Helvetica-Narrow-BoldOblique
NR
NewCenturySchlbk-Roman
NI
NewCenturySchlbk-Italic
NB
NewCenturySchlbk-Bold
NBI
NewCenturySchlbk-BoldItalic
PR
Palatino-Roman
PI
Palatino-Italic
PB
Palatino-Bold
PBI
Palatino-BoldItalic
TR
Times-Roman
TI
Times-Italic
TB
Times-Bold
TBI
Times-BoldItalic
There is also the following font which is not a member of a
family:
ZCMI
ZapfChancery-MediumItalic
There are also some special fonts called S
for the PS Symbol
font, and SS
, containing slanted lowercase Greek letters taken
from PS Symbol. Zapf Dingbats is available as ZD
, and a reversed
version of ZapfDingbats (with symbols pointing in the opposite
direction) is available as ZDR
; most characters in these fonts
are unnamed and must be accessed using \N
.
The default color for \m
and \M
is black; for colors defined in
the 'rgb' color space setrgbcolor
is used, for 'cmy' and 'cmyk'
setcmykcolor
, and for 'gray' setgray
. Note that setcmykcolor
is
a PostScript LanguageLevel 2 command and thus not available on
some older printers.
grops
understands various X commands produced using the \X
escape
sequence; grops
only interprets commands that begin with a ps:
tag.
\X'ps: exec
code'
This executes the arbitrary PostScript commands in code.
The PostScript currentpoint is set to the position of the
\X
command before executing code. The origin is at the
top left corner of the page, and y coordinates increase
down the page. A procedure u
is defined that converts
groff units to the coordinate system in effect (provided
the user doesn't change the scale). For example,
.nr x 1i
\X'ps: exec \nx u 0 rlineto stroke'
draws a horizontal line one inch long. code may make
changes to the graphics state, but any changes persist
only to the end of the page. A dictionary containing the
definitions specified by the def
and mdef
is on top of the
dictionary stack. If your code adds definitions to this
dictionary, you should allocate space for them using \X'ps
mdef
n'
. Any definitions persist only until the end of
the page. If you use the \Y
escape sequence with an
argument that names a macro, code can extend over multiple
lines. For example,
.nr x 1i
.de y
ps: exec
\nx u 0 rlineto
stroke
..
\Yy
is another way to draw a horizontal line one inch long.
Note the single backslash before 'nx' – the only reason to
use a number register while defining the macro 'y' is to
convert a user-specified dimension '1i' to internal groff
units which are in turn converted to PS units with the u
procedure.
grops
wraps user-specified PostScript code into a
dictionary, nothing more. In particular, it doesn't start
and end the inserted code with save
and restore
,
respectively. This must be supplied by the user, if
necessary.
\X'ps: file
name'
This is the same as the exec
command except that the
PostScript code is read from file name.
\X'ps: def
code'
Place a PostScript definition contained in code in the
prologue. There should be at most one definition per \X
command. Long definitions can be split over several \X
commands; all the code arguments are simply joined
together separated by newlines. The definitions are
placed in a dictionary which is automatically pushed on
the dictionary stack when an exec
command is executed. If
you use the \Y
escape sequence with an argument that names
a macro, code can extend over multiple lines.
\X'ps: mdef
n code'
Like def
, except that code may contain up to
n definitions. grops
needs to know how many definitions
code contains so that it can create an appropriately sized
PostScript dictionary to contain them.
\X'ps: import
file llx lly urx ury width [height]'
Import a PostScript graphic from file. The arguments llx,
lly, urx, and ury give the bounding box of the graphic in
the default PostScript coordinate system; they should all
be integers; llx and lly are the x and y coordinates of
the lower left corner of the graphic; urx and ury are the
x and y coordinates of the upper right corner of the
graphic; width and height are integers that give the
desired width and height in groff units of the graphic.
The graphic is scaled so that it has this width and height
and translated so that the lower left corner of the
graphic is located at the position associated with \X
command. If the height argument is omitted it is scaled
uniformly in the x and y directions so that it has the
specified width.
The contents of the \X
command are not interpreted by
troff
; so vertical space for the graphic is not
automatically added, and the width and height arguments
are not allowed to have attached scaling indicators.
If the PostScript file complies with the Adobe Document
Structuring Conventions and contains a %%BoundingBox
comment, then the bounding box can be automatically
extracted from within groff by using the psbb
request.
See groff_tmac(5) for a description of the PSPIC
macro
which provides a convenient high-level interface for
inclusion of PostScript graphics.
\X'ps: invis'
\X'ps: endinvis'
No output is generated for text and drawing commands that
are bracketed with these \X
commands. These commands are
intended for use when output from troff
is previewed
before being processed with grops
; if the previewer is
unable to display certain characters or other constructs,
then other substitute characters or constructs can be used
for previewing by bracketing them with these \X
commands.
For example, gxditview
is not able to display a proper
\(em
character because the standard X11 fonts do not
provide it; this problem can be overcome by executing the
following request
.char \[em] \X'ps: invis'\
\Z'\v'-.25m'\h'.05m'\D'l .9m 0'\h'.05m''\
\X'ps: endinvis'\[em]
In this case, gxditview
is unable to display the \(em
character and draws the line, whereas grops
prints the
\(em
character and ignores the line (this code is already
in file Xps.tmac
which is loaded if a document intended
for grops
is previewed with gxditview
).
If a PostScript procedure BPhook
has been defined via a 'ps: def
'
or 'ps: mdef
' device command, it is executed at the beginning of
every page (before anything is drawn or written by groff). For
example, to underlay the page contents with the word 'DRAFT' in
light gray, you might use
.de XX
ps: def
/BPhook
{ gsave .9 setgray clippath pathbbox exch 2 copy
.5 mul exch .5 mul translate atan rotate pop pop
/NewCenturySchlbk-Roman findfont 200 scalefont setfont
(DRAFT) dup stringwidth pop -.5 mul -70 moveto show
grestore }
def
..
.devicem XX
Or, to cause lines and polygons to be drawn with square linecaps
and mitered linejoins instead of the round linecaps and linejoins
normally used by grops
, use
.de XX
ps: def
/BPhook { 2 setlinecap 0 setlinejoin } def
..
.devicem XX
(square linecaps, as opposed to butt linecaps (0 setlinecap),
give true corners in boxed tables even though the lines are drawn
unconnected).
Encapsulated PostScript
grops
itself doesn't emit bounding box information. With the
help of Ghostscript the following simple script, groff2eps
,
produces an encapsulated PS file.
#! /bin/sh
groff -P-b16 $1 > $1.ps
gs -dNOPAUSE -sDEVICE=bbox -- $1.ps 2> $1.bbox
sed -e "/^%%Orientation/r $1.bbox" \
-e "/^%!PS-Adobe-3.0/s/$/ EPSF-3.0/" $1.ps > $1.eps
rm $1.ps $1.bbox
Just say
groff2eps foo
to convert file foo
to foo.eps
.
TrueType and other font formats
TrueType fonts can be used with grops if converted first to
Type 42 format, a PostScript wrapper equivalent to the PFA format
described in pfbtops(1). Several methods exist to generate a
Type 42 wrapper; some of them involve the use of a PostScript
interpreter such as Ghostscript—see gs
(1).
One approach is to use FontForge ⟨https://fontforge.org/⟩, a font
editor that can convert most outline font formats. Here's an
example of using the Roboto Slab Serif font with groff. Several
variables are used so that you can more easily adapt it into your
own script.
MAP=/usr/local/share/groff/1.23.0/font/devps/generate/textmap
TTF=/usr/share/fonts/truetype/roboto/slab/RobotoSlab-Regular.ttf
BASE=$(basename "$TTF")
INT=${BASE%.ttf}
PFA=$INT.pfa
AFM=$INT.afm
GFN=RSR
DIR=$HOME/.local/groff/font
mkdir -p "$DIR"/devps
fontforge -lang=ff -c "Open(\"$TTF\");\
Generate(\"$DIR/devps/$PFA\");"
afmtodit "$DIR/devps/$AFM" "$MAP" "$DIR/devps/$GFN"
printf "$BASE\t$PFA\n" >> "$DIR/devps/download"
fontforge and afmtodit may generate warnings depending on the
attributes of the font. The test procedure is simple.
printf ".ft RSR\nHello, world!\n" | groff -F "$DIR" > hello.ps
Once you're satisifed that the font works, you may want to
generate any available related styles (for instance, Roboto Slab
also has 'Bold', 'Light', and 'Thin' styles) and set up
GROFF_FONT_PATH in your environment to include the directory you
keep the generated fonts in so that you don't have to use the -F
option.