grops(1): PostScript driver for groff

There are also some special fonts called SS and~S. 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 [rs]N.

The default color for [rs]m and [rs]M is black; for colors defined in the `rgb' color space, setrgbcolor is used, for `cmy' and `cmyk' setcmykcolor, and for `gray' setgray.

grops understands various X~commands produced using the [rs]X escape sequence; grops will only interpret commands that begin with a ps: tag.

[rs]X'ps: exec code'

This executes the arbitrary PostScript commands in code. The PostScript currentpoint will be set to the position of the [rs]X command before executing code. The origin will be at the top left corner of the page, and y~coordinates will increase down the page. A procedure~u will be defined that converts groff units to the coordinate system in effect. For example,

.nr x 1i [rs]X'ps: exec [rs]nx u 0 rlineto stroke'

will draw a horizontal line one inch long. code may make changes to the graphics state, but any changes will persist only to the end of the page. A dictionary containing the definitions specified by the def and mdef will be on top of the dictionary stack. If your code adds definitions to this dictionary, you should allocate space for them using [rs]X'ps mdef n'. Any definitions will persist only until the end of the page. If you use the [rs]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
[rs]nx u 0 rlineto
stroke
..
[rs]Yy

is another way to draw a horizontal line one inch long.

[rs]X'ps: file name'

This is the same as the exec command except that the PostScript code is read from file name.

[rs]X'ps: def code'

Place a PostScript definition contained in code in the prologue. There should be at most one definition per [rs]X command. Long definitions can be split over several [rs]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 [rs]Y escape sequence with an argument that names a macro, code can extend over multiple lines.

[rs]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.

[rs]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 will be 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 [rs]X command. If the height argument is omitted it will be scaled uniformly in the x and y~directions so that it has the specified width. Note that the contents of the [rs]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.

The -mps macros (which are automatically loaded when grops is run by the groff command) include a PSPIC macro which allows a picture to be easily imported. This has the format

.PSPIC [-L|-R|-I n] file [width [height]]

file is the name of the file containing the illustration; width and height give the desired width and height of the graphic. The width and height arguments may have scaling indicators attached; the default scaling indicator is~i. This macro will scale the graphic uniformly in the x and y~directions so that it is no more than width wide and height high. By default, the graphic will be horizontally centered. The -L and -R cause the graphic to be left-aligned and right-aligned respectively. The -I option causes the graphic to be indented by~n.

[rs]X'ps: invis'

[rs]X'ps: endinvis'

No output will be generated for text and drawing commands that are bracketed with these [rs]X commands. These commands are intended for use when output from troff will be 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 [rs]X commands.

For example, gxditview is not able to display a proper [rs](em character because the standard X11 fonts do not provide it; this problem can be overcome by executing the following request

.char [rs](em [rs]X'ps: invis'[rs]
[rs]Z'[rs]v'-.25m'[rs]h'.05m'[rs]D'l .9m 0'[rs]h'.05m''[rs]
[rs]X'ps: endinvis'[rs](em

In this case, gxditview will be unable to display the [rs](em character and will draw the line, whereas grops will print the [rs](em character and ignore the line.

The input to grops must be in the format output by troff(1). This is described in (5). In addition the device and font description files for the device used must meet certain requirements. The device and font description files supplied for ps device meet all these requirements. afmtodit(1) can be used to create font files from AFM files. 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 should contain a command

paperlength n

which says that output should be generated which is suitable for printing on a page whose length is n~machine units. Common values are 792000 for letter paper and 841890 for paper in A4 format. Alternatively, it can contain

papersize string

to specify a paper size; see (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. 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 [rs]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 will assume 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.

grops can automatically include the downloadable fonts necessary to print the document. Any downloadable fonts which should, when required, be included by grops must be listed in the file /usr/share/groff/1.18.1.1/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 will be searched for using the same mechanism that is used for groff font metric files. The download file itself will also be 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 will interpret any comments in the files sufficiently to ensure that its own output is conforming. It will also supply 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 be appear before Garamond-Outline in the PostScript document. grops will handle 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 will not interpret %%DocumentFonts comments. The %%DocumentNeededResources, %%DocumentSuppliedResources, %%IncludeResource, %%BeginResource and %%EndResource comments (or possibly the old %%DocumentNeededFonts, %%DocumentSuppliedFonts, %%IncludeFont, %%BeginFont and %%EndFont comments) should be used.

TrueType fonts

TrueType fonts can be used with grops if converted first to Type 42 format, an especial PostScript wrapper equivalent to the PFA format mentioned in pfbtops(1). There are several different methods to generate a type42 wrapper and most of them involve the use of a PostScript interpreter such as Ghostscript --- see gs(1). Yet, the easiest method involves the use of the application ttftot42. This program uses freetype(3) (version 1.3.1) to generate type42 font wrappers and well-formed AFM files that can be fed to the afmtodit(1) script to create appropriate metric files. The resulting font wrappers should be added to the download file. ttftot42 source code can be downloaded from

ENVIRONMENT

GROPS_PROLOGUE: If this is set to foo, then grops will use the file foo (in the font path) instead of the default prologue file prologue. The option -P overrides this environment variable.

FILES

u+2n

/usr/share/groff/1.18.1.1/font/devps/DESC Device description file.
/usr/share/groff/1.18.1.1/font/devps/F: Font description file for font F.
/usr/share/groff/1.18.1.1/font/devps/download: List of downloadable fonts.
/usr/share/groff/1.18.1.1/font/devps/text.enc: Encoding used for text fonts.
/usr/share/groff/1.18.1.1/tmac/ps.tmac: Macros for use with grops; automatically loaded by troffrc
/usr/share/groff/1.18.1.1/tmac/pspic.tmac: Definition of PSPIC macro, automatically loaded by ps.tmac.
/usr/share/groff/1.18.1.1/tmac/psold.tmac: Macros to disable use of characters not present in older PostScript printers (e.g. `eth' or `thorn').
/tmp/gropsXXXXXX: Temporary file.