.ig
www.tmac - macro package for adding HTML elements to roff documents.

File position: <groff_source_top>/tmac/www.tmac
Installed position: groff's main macro directory.

------------------------------------------------------------------------
    Legalize
------------------------------------------------------------------------

This file is part of groff, the GNU roff type-setting system.

Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
written by Gaius Mulley <gaius@glam.ac.uk>, with additions by
Werner Lemberg <wl@gnu.org> and Bernd Warken <bwarken@mayn.de>.

groff is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.

groff is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with groff; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.


------------------------------------------------------------------------
    Description
------------------------------------------------------------------------

A simple set of macros to provide HTML documents with basic
www functionality.  It should work with any macro set.
..
.
.\" --------------------------------------------------------------------
.\" Setup
.\" --------------------------------------------------------------------
.
.nr _C \n(.C
.cp 0
.
.nr www-html 0
.if '\*[.T]'html' .nr www-html 1
.
.\" set up www-image-template
.
.if !d www-image-template \
.  ds www-image-template
.
.if r ps4html \{\
.  \" remove the title command when we are generating images for html
.  \" (stops a title accidentally appearing inside an image)
.  di www-notitle
.  tl ''''
.  di
.  rm tl
.  de tl
.  .
.\}
.
.
.\" --------------------------------------------------------------------
.\" Test for `.substring'; result in register `www.substring_ok'.
.\" The automated break points in .URL addresses are only added if
.\" this register is non-zero.
.\"
.nr www:substring_ok 0
.de www:@test_substring
.  if !d substring \
.    return
.  ds \\$0:s abcdefg\"
.  substring \\$0:s 1 1
.  if !'\\*[\\$0:s]'b' \{\
.    rm \\$0:s
.    return
.  \}
.  ds \\$0:s abcdefg\"
.  substring \\$0:s 0 0
.  if !'\\*[\\$0:s]'a' \{\
.    rm \\$0:s
.    return
.  \}
.  ds \\$0:s abcdefg\"
.  substring \\$0:s 1 -1
.  if !'\\*[\\$0:s]'bcdefg' \{\
.    rm \\$0:s
.    return
.  \}
.  nr www:substring_ok 1
.  rm \\$0:s
..
.www:@test_substring
.rm www:@test_substring
.
.
.\" --------------------------------------------------------------------
.\" Local Macros
.\" --------------------------------------------------------------------
.
.\" --------------------------------------------------------------------
.\" www:error (<test>...)
.\"
.\" Print error message
.\"
.de www-error
.  tm \\n[.F]:\\n[.c]: macro error: \\$*
..
.als www:error www-error
.
.\" --------------------------------------------------------------------
.\" www:lenstr (<register_name> <string_name>)
.\"
.\" Store length of string named <string_name> into register named
.\" <register_name>.
.\"
.de www:lenstr
.  if !(\\n[.$] == 2) \{\
.    tm .\\$0 expects 2 arguments.
.    ab
.  \}
.  length \\$0:n x\\*[\\$2]
.  nr \\$1 (\\n[\\$0:n]-1)
.  rr \\$0:n
..
.\" --------------------------------------------------------------------
.\" www:splitstr (<name>)
.\"
.\" Add a space character between any two adjacent characters in string
.\" <name> and restore result into the string variable <name>; space
.\" characters are first replaced by the word `space'.
.\"
.de www:splitstr
.  if !(\\n[.$] == 1) \
.    www:error .\\$0 expects 1 argument.
.  if '\\*[\\$1]'' \
.    return
.  ds \\$0:r "\\*[\\$1]\""
.  ds \\$0:s\"
.  while 1 \{\
.    ds \\$0:c "\\*[\\$0:r]\""
.    substring \\$0:c 0 0\"
.    ie '\\*[\\$0:c]' ' \
.      as \\$0:s " space\""
.    el \
.      as \\$0:s " \\*[\\$0:c]\""
.    www:lenstr \\$0:n \\$0:r
.    if (\\n[\\$0:n] <= 1) \{\
.      break
.    \}
.    substring \\$0:r 1 -1\"
.  \}
.  if !'\\*[\\$0:s]'' \
.    substring \\$0:s 1 -1 
.  ds \\$1 \\*[\\$0:s]
.  rm \\$0:c
.  rr \\$0:n
.  rm \\$0:r
.  rm \\$0:s
..
.\" --------------------------------------------------------------------
.\" www:url_breaks (<string_name>)
.\"
.\" Add `\:' (possible break point) within URL strings after `/'.
.\"
.\" Smart about multiple `/', existing `\:', and space characters;
.\" does not set a break point if less than 5 characters would go to
.\" the next line.
.\"
.de www:url_breaks
.  if !(\\n[.$] == 1) \
.    www:error .\\$0 expects 1 argument.
.  if !\n[www:substring_ok] \
.    return
.  ds \\$0:s "\\*[\\$1]\""
.  www:splitstr \\$0:s
.  www:url_breaks_splitted \\$0:s \\*[\\$0:s]
.  ds \\$1 "\\*[\\$0:s]\""
.  rm \\$0:s
..
.\" --------------------------------------------------------------------
.\" www:url_breaks_splitted (<result> <char> [<char>...])
.\"
.\" Add `\:' within URL strings, but arguments are a splitted string.
.\"
.\" Arguments: >=2: <result> <char> [<char>...]
.\"
.de www:url_breaks_splitted
.  nr \\$0:min 5             \" minimal number of characters for next line
.  if (\\n[.$] < 2) \
.    www:error .\\$0 expects at least 2 arguments.
.  ds \\$0:res \\$1\"
.  shift
.  ds \\$0:s\"
.  nr \\$0:done 0
.  while !\\n[\\$0:done] \{\
.    if (\\n[.$] <= 0) \{\
.      nr \\$0:done 1
.      break
.    \}
.    if '\\$1'space' \{\
.      as \\$0:s " \""
.      shift
.      continue
.    \}
.    if (\\n[.$] < \\n[\\$0:min]) \{\
.      as \\$0:s "\\$1\""
.      shift
.      continue
.    \}
.    if !'\\$1'/' \{\
.      as \\$0:s "\\$1\""
.      shift
.      continue
.    \}
.    \" we are at a `/' character
.    while '\\$1'/' \{\
.      as \\$0:s /\"
.      if (\\n[.$] == 0) \{\
.        nr \\$0:done 1
.        break
.      \}
.      shift
.    \}
.    if \\n[\\$0:done] \
.      break
.    if (\\n[.$] < \\n[\\$0:min]) \
.      continue
.    if '\\$1'\:' \
.      shift
.    as \\$0:s \:\"
.  \}
.  ds \\*[\\$0:res] \\*[\\$0:s]\"
.  rm \\$0:res
.  rm \\$0:s
..
.\" --------------------------------------------------------------------
.\" User Interface
.\" --------------------------------------------------------------------
.
.\" --------------------------------------------------------------------
.\" HTML (<address> <description> [<punctuation>])
.\"
.\" the main auxiliary macro for the HTML interface
.\"
.de HTML
.  if \\n[www-html] \{\
.    \" the following line makes the vertical mode leave, so to say
.    nop \&
.    nop \X^html:\\$*^
.  \}
..
.\"
.\" an auxiliary macro for HTML (without following space)
.\"
.de HTML-NS
.  if \\n[www-html] \
.    nop \X^html:\\$*^\c
..
.\" --------------------------------------------------------------------
.\" HX n
.\"
.\"   Automatic heading level cut off.
.\"
.\"   N is the depth limit of automatically linked headings.  So a depth
.\"   of 2 would cause grohtml to generate a list of links for `.NH 1'
.\"   and `.NH 2' but not for `.NH 3'.
.\"
.de HX
.  if \\n[www-html] \
.    nop \X^index:\\$*^
..
.\" --------------------------------------------------------------------
.\" BCL foreground background active not-visited visited
.\"
.de BCL
.  HTML <body text=\\$1 bgcolor=\\$2 link=\\$3 alink=\\$4 vlink=\\$5>
..
.\" --------------------------------------------------------------------
.\" BGIMG imagefile
.\"
.de BGIMG
.  HTML <body background=\\$1>
..
.\" --------------------------------------------------------------------
.\" URL url [description] [after]
.\"     if description is absent then the url becomes the anchor text
.\"
.de URL
.  ds \\$0:adr \\$1\"
.  www:url_breaks \\$0:adr
.  ie \\n[www-html] \{\
.    ie '\\$2'' \
.       HTML <a href="\\$1">\\$1</a>\\$3
.    el \
.       HTML <a href="\\$1">\\$2</a>\\$3
.  \}
.  el \{\
.    if !r ps4html .ad l
.    ie '\\$2'' \
.       nop \%\[la]\m[blue]\f[C]\\*[\\$0:adr]\f[]\m[]\[ra]\\$3
.    el \
.       nop \m[blue]\\$2\m[] \%\[la]\f[C]\\*[\\$0:adr]\f[]\[ra]\\$3
.    if !r ps4html .ad
.  \}
.  rm \\$0:adr
..
.\" --------------------------------------------------------------------
.\" FTP url description [after]
.\"
.\"   Same as URL.
.\"
.als FTP URL
.\" --------------------------------------------------------------------
.\" MTO address description [after]
.\"
.\"   ADDRESS is the email address (without the `mailto:' prefix).
.\"
.\"   DESCRIPTION is the optional name.  If an empty argument is given,
.\"   ADDRESS is used instead.
.\"
.\"   AFTER is optional stuff printed immediately after ADDRESS
.\"   (resp. DESCRIPTION).
.\"
.\"     Example:
.\"
.\"       Foobar has been written by
.\"       .MTO fred@foo.bar "Fredrick Bloggs" .
.\"
.de MTO
.  ie \\n[www-html] \{\
.    ie '\\$2'' \
.      URL mailto:\\$1 \\$1 "\\$3"
.    el \
.      URL mailto:\\$1 "\\$2" "\\$3"
.  \}
.  el \{\
.    ie '\\$2'' \
.      nop \%\m[blue]\f[C]\\$1\f[]\m[]\\$3
.    el \
.      nop \m[blue]\\$2\m[] \%\[la]\f[C]\\$1\f[]\[ra]\\$3
.  \}
..
.\" --------------------------------------------------------------------
.\" TAG name
.\"
.\"   Generate an html name NAME.
.\"
.de TAG
.  HTML <a name="\\$1"></a>
..
.\" --------------------------------------------------------------------
.\" IMG [-R|-L|-C] filename [width] [height]
.\"
.\"   Include an image of any type (will only work for -Thtml).
.\"
.\"   Alignment is centered by default (-C).
.\"   Default value for WIDTH is 1i.
.\"   If HEIGHT is not given, WIDTH is used as the height.
.\"
.de IMG
.  ie \\n[www-html] \{\
.    ie '\\$2'-R' \
.      HTML-TAG ".right-image"
.    el \{\
.      ie '\\$2'-L' \
.        HTML-TAG ".left-image"
.      el \
.        HTML-TAG ".centered-image"
.    \}
.    nr www-width 100
.    if !'\\$3'' \
.      nr www-width \\$3
.    nr www-height \\n[www-width]
.    if !'\\$4'' \
.      nr www-height \\$4
.    HTML <img src="\\$1" width=\\n[www-width] height=\\n[www-height]>
.  \}
.  el \
.    nop \[la]\f[C]\\$1\f[]\[ra]
..
.\" --------------------------------------------------------------------
.\" HTML-TAG
.\"
.\"   Emit a tag for grohtml.  This is an internal macro.
.\"
.de HTML-TAG
.  if \\n[www-html] \{\
.    \" the following line makes the vertical mode leave, so to say
.    nop \&
.    nop \X^html-tag:\\$*^
.  \}
..
.\" --------------------------------------------------------------------
.\" HTML-TAG-NS
.\"
.\"   Emit a tag for grohtml (without a space).  This is an internal macro.
.\"
.de HTML-TAG-NS
.  if \\n[www-html] \
.    nop \X^html-tag:\\$*^\c
..
.\" --------------------------------------------------------------------
.\" PIMG  [-R|-L|-C] filename [width] [height]
.\"
.\"   Include a png image.  It will work for -Tps and -Thtml.
.\"   The default value for WIDTH and HEIGHT is zero; the default
.\"   alignment is centering (-C).
.\"
.\" Note: This macro can only be used with the `-U' option of groff,
.\"       activating unsafe mode, if not used with -Thtml; the PNG image
.\"       is then converted to the EPS format using netpbm utilities.
.\"
.de PIMG
.  ie \\n[www-html] \{\
.    ie '\\$1'-R' \
.      HTML-TAG ".right-image"
.    el \{\
.      ie '\\$1'-L' \
.        HTML-TAG ".left-image"
.      el \
.        HTML-TAG ".centered-image"
.    \}
.    nr www-width 0
.    nr www-height 0
.    if !'\\$3'' \
.      nr www-width (\\$3 * 100 / 240)
.    if !'\\$4'' \
.      nr www-height (\\$4 * 100 / 240)
.    ie (\\n[www-width] == 0) \{\
.      ie (\\n[www-height] == 0) \
.        HTML <img src="\\$2">
.      el \
.        HTML <img src="\\$1" height=\\n[www-height]>
.    \}
.    el \{\
.      ie (\\n[www-height] == 0) \
.        HTML <img src="\\$2" width=\\n[www-width]>
.      el \
.        HTML <img src="\\$2" width=\\n[www-width] height=\\n[www-height]>
.    \}
.  \}
.  el \{\
.    if !r ps4html \{\
.      www-make-unique-name
.      sy pngtopnm \\$2 | pnmcrop -white | @PNMTOPS_NOSETPAGE@ -noturn > \\*[www-unique-name].eps
.      ie '\\$1'-C' \
.        PSPIC \\*[www-unique-name].eps \\$3 \\$4
.      el \
.        PSPIC \\$1 \\*[www-unique-name].eps \\$3 \\$4
.    \}
.  \}
..
.
.\" --------------------------------------------------------------------
.\" auxiliary definitions for MPIMG
.\"
.nr www-left-ll-trap 0
.nr www-left-po-trap 0
.nr www-right-ll-trap 0
.
.de www-finish-left-po
.  po -(\\n[www-left-indent]u + \\n[www-image-gap]u)
.  wh \\n[www-left-po-trap]u
.  nr www-left-indent 0
..
.
.\" called when the -R picture is finished
.de www-finish-right-ll
.  ll +(\\n[www-right-indent]u + \\n[www-image-gap]u)
.  \" now see whether we need to inline www-finish-left-ll
.  if (\\n[www-left-ll-trap]u > 0) \
.    if ((\\n[www-right-ll-trap]u + 1v) >= \\n[www-left-ll-trap]u) \{\
.      mk www-left-po-trap
.      nr www-left-po-trap +1v
.      wh \\n[www-left-po-trap]u www-finish-left-po
.      ll +\\n[www-left-indent]u
.      wh \\n[www-left-ll-trap]u
.      nr www-left-ll-trap 0
.    \}
.  \" and see whether we need to inline www-finish-left-po
.  if (\\n[www-left-po-trap]u > 0) \
.    if ((\\n[www-right-ll-trap]u + 1v) >= \\n[www-left-po-trap]u) \{\
.      po -\\n[www-left-indent]u
.      wh \\n[www-left-po-trap]u
.      nr www-left-indent 0
.    \}
.  wh \\n[www-right-ll-trap]u
.  nr www-right-ll-trap 0
..
.
.de www-finish-left-ll
.  if (\\n[www-right-ll-trap] > 0) \
.    if ((\\n[www-left-ll-trap] + 1v) >= \\n[www-right-ll-trap]) \{\
.      ll +\\n[www-right-indent]u
.      nr www-right-ll-trap 0
.    \}
.  mk www-left-po-trap
.  nr www-left-po-trap +1v
.  wh \\n[www-left-po-trap]u www-finish-left-po
.  ll +(\\n[www-left-indent]u + \\n[www-image-gap]u)
.  wh \\n[www-left-ll-trap]u
.  nr www-left-ll-trap 0
..
.\" --------------------------------------------------------------------
.\" MPIMG [-R|-L] [-G gap] filename [width [height]]
.\"
.\"   Include a png image and wrap text around it.  It will work for
.\"   -Tps and -Thtml.  The default value for WIDTH is 1i; default value
.\"   for HEIGHT is WIDTH; the default alignment is left (-L).
.\"   -G is used to insert a gap between the text and the image.
.\"
.\" Note: This macro can only be used with the `-U' option of groff,
.\"       activating unsafe mode, if not used with -Thtml; the PNG image
.\"       is then converted to the EPS format using netpbm utilities.
.\"
.
.nr www-htmlimage-gap 0
.
.de MPIMG
.  nr www-image-just 1
.  nr www-image-gap 0
.  while (\\n[.$] > 0) \{\
.    if '-L'\\$1' \{\
.      nr www-image-just 1
.      shift
.      continue
.    \}
.    if '-R'\\$1' \{\
.      nr www-image-just 0
.      shift
.      continue
.    \}
.    if '-G'\\$1' \{\
.      nr www-image-gap \\$2
.      nr www-htmlimage-gap (\\$2 * 100 / 240)
.      shift 2
.      continue
.    \}
.    break
.  \}
.  nr www-width 1i
.  if !'\\$2'' \
.    nr www-width \\$2
.  nr www-height \\n[www-width]
.  if !'\\$3'' \
.    nr www-height \\$3
.  nr www-width (\\n[www-width] * 100 / 240)
.  nr www-height (\\n[www-height] * 100 / 240)
.
.  ie \\n[www-html] \{\
.    ie !\\n[www-image-just] \
.      HTML <img src="\\$1" hspace=\\n[www-htmlimage-gap] \
             align=right width=\\n[www-width] height=\\n[www-height]>
.    el \
.      HTML <img src="\\$1" hspace=\\n[www-htmlimage-gap] \
             align=left width=\\n[www-width] height=\\n[www-height]>
.  \}
.  el \{\
.    if !r ps4html \{\
.      www-make-unique-name
.      sy pngtopnm \\$1 | pnmcrop -white | @PNMTOPS_NOSETPAGE@ -noturn > \\*[www-unique-name].eps
.      ie !\\n[www-image-just] \{\
.        \" we must now disable a possible left image trap
.        sp -1
.        if (\\n[www-left-ll-trap] > 0) \
.          wh \\n[www-left-ll-trap]u
.        if (\\n[www-left-po-trap] > 0) \
.          wh \\n[www-left-po-trap]u
.        PSPIC -R \\*[www-unique-name].eps \\$2 \\$3
.        sp -\\n[ps-desht]u
.        nr www-right-indent \\n[ps-deswid]u
.        \" we want to have some space between text and image,
.        \" so the line length must be shorter
.        ll -(\\n[www-right-indent]u + \\n[www-image-gap]u)
.        mk www-right-ll-trap
.        nr www-right-ll-trap +(\\n[ps-desht]u - 1v)
.        wh \\n[www-right-ll-trap]u www-finish-right-ll
.        \" now restore possible left trap
.        if (\\n[www-left-ll-trap] > 0) \
.          wh \\n[www-left-ll-trap]u www-finish-left-ll
.        if (\\n[www-left-po-trap] > 0) \
.          wh \\n[www-left-po-trap]u
.      \}
.      el \{\
.        \" we must now disable a possible right image trap
.        if (\\n[www-right-ll-trap] > 0) \
.          wh \\n[www-right-ll-trap]u
.        PSPIC -L \\*[www-unique-name].eps \\$2 \\$3
.        sp -\\n[ps-desht]u
.        nr www-left-indent \\n[ps-deswid]u
.        \" increase offset by gap
.        po +(\\n[www-left-indent]u + \\n[www-image-gap]u)
.        \" decrease line length by gap
.        ll -(\\n[www-left-indent]u + \\n[www-image-gap]u)
.        mk www-left-ll-trap
.        nr www-left-ll-trap +(\\n[ps-desht]u - 1v)
.        wh \\n[www-left-ll-trap]u www-finish-left-ll
.        \" now restore possible right trap
.        if (\\n[www-right-ll-trap] > 0) \
.          wh \\n[www-right-ll-trap]u www-finish-right-ll
.      \}
.    \}
.  \}
..
.\" --------------------------------------------------------------------
.\" HnS n
.\"
.\"   Begin heading.  Heading level is N.
.\"
.\" HnE
.\"
.\"   End heading.
.\"
.\" If your heading contains URL, FTP, MTO macros you might wish to
.\" disable automatic links to headings.  This can be done via `-P-l'
.\" from the command line or by using a cakk to `.HX 0'.
.\"
.nr www-heading-no -1
.
.de HnS
.  ie '\\$1'' \
.    nr www-heading-no 1
.  el \
.    nr www-heading-no \\$1
.  HTML-TAG ".NH \\n[www-heading-no]"
..
.
.de HnE
.  if (\\n[www-heading-no] == -1) \
.    www-error "HnE found without a corresponding HnS"
.  br
..
.\" --------------------------------------------------------------------
.\" LK
.\"
.\"   Emit the automatically collected links derived from
.\"   section/numbered headings at this position.
.\"
.de LK
.  HTML-TAG ".links"
..
.\" --------------------------------------------------------------------
.\" HR
.\"
.\"   Produce a horizontal line
.\"
.de HR
.  ie \\n[www-html] \{\
.    ti 0
.    HTML-NS <hr>
.  \}
.  el \
.    sp
..
.\" --------------------------------------------------------------------
.\" NHR
.\"
.\"  Suppresses the generation of the top and bottom rules which grohtml
.\"  emits by default.
.\"
.de NHR
.  HTML-TAG ".no-auto-rule"
..
.\"
.\" www-end-nowhere - end of input trap called to finish diversion.
.\"
.de www-end-nowhere
.  di
..
.\" --------------------------------------------------------------------
.\" HTL
.\"
.\"   Generate an HTML title only.  This differs from the -ms .TL macro
.\"   which generates both an HTML title and a H1 heading.
.\"
.\"   This is useful when an author wishes to use a HTML title as search
.\"   engine fodder but a graphic title in the document.
.\"
.\"   The macro terminates when a space or break is seen (.sp, .br).
.\"
.de HTL
.  HTML-TAG ".html-tl"
.  if !\\n[www-html] \{\
.    di www-nowhere
.    it 2 www-end-nowhere
.  \}
..
.
.\" --------------------------------------------------------------------
.\" auxiliary definitions for ULS / ULE
.\"
.ds www-level1 \[bu]\ \ \"
.ds www-level2 \[sq]\ \ \"
.ds www-level3 \[ci]\ \ \"
.nr www-level 0
.nr www-depth 0
.
.\"
.\" Auxiliary macro for ULS.
.\"
.de www-push-level
.  nr www-level +1
.  if (\\n[www-level] > 3) \
.    www-error "too many levels of indentation (\\n[www-level])"
..
.\"
.\" Auxiliary macro for ULE.
.\"
.de www-pop-level
.  if !\\n[www-level] \
.    www-error "trying to terminate a list which does not exist"
.  nr www-level -1
..
.\" --------------------------------------------------------------------
.\" ULS
.\"
.\"   Start an unordered list.
.\"
.de ULS
.  www-push-level
.  ie \\n[www-html] \
.    HTML "<ul>"
.  el \{\
.    if (\\n[www-level] == 1) \
.      nr www-depth \\n[.i]
.    nr www-depth +\w'\\*[www-level\\n[www-level]]'u
.  \}
..
.\" --------------------------------------------------------------------
.\" ULE
.\"
.\"   End an unordered list.
.\"
.de ULE
.  ie \\n[www-html] \
.    HTML "</ul>"
.  el \{\
.    nr www-depth -\w'\\*[www-level\\n[www-level]]'u
.    in \\n[www-depth]u
.  \}
.  www-pop-level
..
.\" --------------------------------------------------------------------
.\" LI
.\"
.\"   Insert a list item.
.\"
.de LI
.  ie \\n[www-html] \
.    HTML "<li>"
.  el \{\
.    in \\n[www-depth]u
.    ti -\w'\\*[www-level\\n[www-level]]'u
.    nop \\*[www-level\\n[www-level]]\c
.  \}
..
.\" --------------------------------------------------------------------
.\" DC l text [color]
.\"
.\"   L is the letter to be dropped and enlarged.
.\"
.\"   TEXT is the following text whose height the first letter should not
.\"   exceed.
.\"
.\"   COLOR is the optional color of the dropped letter (default black).
.\"
.de DC
.  ds www-dropcolor black
.  if !'\\$3'' \
.    ds www-dropcolor \\$3
.  ie '\*(.T'html' \{\
.    www-make-unique-name
.    MPIMG -L \\*[www-unique-name].png "(\\n[.v] * 2u)"
.  \}
.  el \{\
.    ie r ps4html \{\
.      www-make-unique-name
.      \" To avoid interferences with another DC macro call which is located
.      \" very near to the current one, we draw the glyph on a separate page.
.      \" Otherwise it could theoretically happen that the dropped capital
.      \" glyphs overlap.
.      bp
.      ev www-DC
.      vs 80p
.      nop \O[5i\\*[www-unique-name].png]\O[1]
.      nop \m[\\*[www-dropcolor]]\s[40]\O[3]\\$1\O[4]
.      nop \O[2]\O[0]
.      br
.      ev
.      bp
.    \}
.    el \{\
.      ie n \
.        nop \\$1\c
.      el \{\
.        nr dummy \w'\\$1'u
.        nr dcht ((\\n[.v] + \\n[rst]) * \\n[.ps] / \\n[rst])
.        char \[dcap] \m[\\*[www-dropcolor]]\s'\\n[dcht]u'\\$1
.        nop \v'\\n[.v]u'\\[dcap]\v'-\\n[.v]u'\c
'        ti \w'\\[dcap]'u
.      \}
.    \}
.  \}
.  nop \\$2
..
.\" --------------------------------------------------------------------
.\" Setup around HTML-IMAGE and friends
.\"
.\" now set up TS, TE, EQ, EN default macros
.\"
.do if !d TS .do ds TS HTML-IMAGE
.do if !d TE .do ds TE HTML-IMAGE-END
.do if !d EQ .do ds EQ HTML-IMAGE
.do if !d EN .do ds EN HTML-IMAGE-END
.\"
.\" supplementary macros used by other macro sets
.\"
.\" here are some tags specially for -Tps or -Thtml when invoked by
.\" pre-html to generate png images from postscript.
.
.\" --------------------------------------------------------------------
.\" HTML-DO-IMAGE - tells troff to issue an image marker which can be
.\"                 read back by pre-html
.\"
.de HTML-DO-IMAGE
.  if r ps4html \
.    nop \O[5\\$2\\$1.png]\O[1]\O[3]
.  if \\n[www-html] \
.    nop \O[5\\$2\\$1.png]\O[0]\O[3]
..
.\" --------------------------------------------------------------------
.\" HTML-IMAGE-END - terminates an image for html
.\"
.de HTML-IMAGE-END
.  if r ps4html \
.    nop \O[4]\O[2]\O[0]
.  if \\n[www-html] \
.    nop \O[4]\O[2]\O[1]
..
.
.nr www-png-no 0
.
.\" --------------------------------------------------------------------
.\" www-make-unique-name - generates another unique name in string
.\"                        `www-unique-name'
.\"
.de www-make-unique-name
.  nr www-png-no +1
.  ds www-unique-name \\*[www-image-template]\\n[www-png-no]
..
.\" --------------------------------------------------------------------
.\" HTML-IMAGE and friends tell grohtml that this region of text needs
.\"            to be rendered as an image.
.\"
.de HTML-IMAGE
.  \" generates a centered image
.  www-make-unique-name
.  HTML-DO-IMAGE \\*[www-unique-name] c
..
.
.de HTML-IMAGE-RIGHT
.  www-make-unique-name
.  HTML-DO-IMAGE \\*[www-unique-name] r
..
.
.de HTML-IMAGE-LEFT
.  www-make-unique-name
.  HTML-DO-IMAGE \\*[www-unique-name] l
..
.
.de HTML-IMAGE-INLINE
.  www-make-unique-name
.  HTML-DO-IMAGE \\*[www-unique-name] i
..
.
.\" --------------------------------------------------------------------
.\" JOBNAME
.\"
.\"   Generate multiple output files containing the html.
.\"   A file is split whenever a .SH or .NH 1 is encountered.
.\"   The argument to JOBNAME is the file stem for future output files.
.\"
.de JOBNAME
.  HTML-TAG .job-name \\$1
..
.\" --------------------------------------------------------------------
.\" Final Setup
.\" --------------------------------------------------------------------
.
.if \n[www-html] \{\
.   nh
.   nr HY 0
.\}
.
.\"
.\" start of some code
.\"
.
.de CDS
.ft C
.nf
..
.\"
.\" end of some code
.\"
.
.de CDE
.fi
.ft P
..
.
.if r ps4html .nop \O[0]
.cp \n(_C
.
.\" now set
.
.\" --------------------------------------------------------------------
.\" Emacs settings
.\" --------------------------------------------------------------------
.
.\" Local Variables:
.\" mode: nroff
.\" End:
.\" EOF