.\"
.\" MN.tmac
.\"
.\" written by Werner Lemberg <address@hidden>
.\"
.\" Version 0.1: 13-Dec-2002
.\"
.\"
.\" Usage:
.\"
.\"   ...
.\"   MN [left|right]
.\"   margin note text
.\"   MN
.\"   ...
.\"
.\" With a parameter, start a margin note, otherwise end a margin note.
.\" If the parameter is the string `left', define a left margin note,
.\" otherwise define a right margin note.
.\"
.de MN
.  ie \\n[.$] \{\
.    if \\n[MN-active] \{\
.      tm MN: Can't handle nested margin notes.
.      return
.    \}
.    nr MN-active 1
.    ie '\\$1'left' \{\
.      nr MN-left +1
.      ds MN-curr l-\\n[MN-left]
.    \}
.    el \{\
.      nr MN-right +1
.      ds MN-curr r-\\n[MN-right]
.    \}
.
.    mk MN-mk-\\*[MN-curr]
.    ev MN-env
.    di MN-div-\\*[MN-curr]
.  \}
.  el \{\
.    if \\n[MN-active] \{\
.      br
.      di
.      unformat MN-div-\\*[MN-curr]
.      ev
.    \}
.    nr MN-active 0
.  \}
..
.
.
.\"
.\" This macro must be installed as a trap macro before the first
.\" margin note on a page can occur.  It initializes some variables.
.\"
.de MNtop
.  nr MN-left 0
.  nr MN-right 0
.  nr MN-active 0
..
.
.
.\"
.\" This macro must be installed as a trap macro after the last
.\" margin note on a page can occur.  It prints the margin notes
.\" into the left and right margins.
.\"
.de MNbottom
.  nr MN-curr 0
.  nr MN-last-pos 0
.
.  vpt 0
.
.  mk MN-curr-pos
.
.  if \\n[MN-active] \{\
.    di
.    tm MN: Margin note finished by new page.  Ignored.
.  \}
.
.  po \\n[MN-left-start]u
.  ev MNbottom-left-env
.  while (\\n[MN-curr] < \\n[MN-left]) \{\
.    nr MN-curr +1
.    ie (\\n[MN-last-pos] < \\n[MN-mk-l-\\n[MN-curr]]) \
.      sp |\\n[MN-mk-l-\\n[MN-curr]]u
.    el \{\
.      sp
.      tm MN: Warning: Left margin note #\\n[MN-curr] on page \\n[%] shifted 
down.
.    \}
.    MN-div-l-\\n[MN-curr]
.    br
.    nr MN-last-pos \\n[nl]
.  \}
.  ev
.  po
.
.  nr MN-curr 0
.  nr MN-last-pos 0
.  po \\n[MN-right-start]u
.  ev MNbottom-right-env
.  while (\\n[MN-curr] < \\n[MN-right]) \{\
.    nr MN-curr +1
.    ie (\\n[MN-last-pos] < \\n[MN-mk-r-\\n[MN-curr]]) \
.      sp |\\n[MN-mk-r-\\n[MN-curr]]u
.    el \{\
.      sp
.      tm MN: Warning: Right margin note #\\n[MN-curr] on page \\n[%] shifted 
down.
.    \}
.    MN-div-r-\\n[MN-curr]
.    br
.    nr MN-last-pos \\n[nl]
.  \}
.  ev
.  po
.
'  sp |\\n[MN-curr-pos]u
.
.  vpt 1
..
.
.
.\"
.\" MNinit [ragged|symmetric] \
.\"        left-width right-width separation \
.\"        font fontsize vertical-spacing
.\"
.\" Initialize margin notes.  Empty arguments (denoted with "") set
.\" default values.  If the first argument is the string `ragged',
.\" left and right margin notes are printed ragged-right.  If it is
.\" `symmetric', left margin notes are printed ragged-left and right
.\" margin notes ragged-right.  If omitted, margin notes are left
.\" and right adjusted.
.\"
.de MNinit
.  ds MN-left-ad b
.  ds MN-right-ad b
.  if '\\$1'ragged' \{\
.    ds MN-left-ad l
.    ds MN-right-ad l
.    shift
.  \}
.  if '\\$1'symmetric' \{\
.    ds MN-left-ad r
.    ds MN-right-ad l
.    shift
.  \}
.
.  ie \B'\\$3' \
.    nr MN-sep (n;\\$3)
.  el \
.    nr MN-sep 1n
.  if ((\\n[.o] - \\n[MN-sep]) < 1n) \
.    ab MN: Left margin too small (<1n) for requested margin notes separation.
.
.  ie \B'\\$1' \{\
.    nr MN-left-width (n;\\$1)
.    nr MN-left-start (\\n[.o] - \\n[MN-sep] - \\n[MN-left-width])
.  \}
.  el \{\
.    nr MN-left-width (\\n[.o] - \\n[MN-sep])
.    nr MN-left-start 0
.  \}
.  if (\\n[MN-left-start] < 0) \
.    ab MN: Left margin too small for requested margin notes settings.
.  if (\\n[MN-left-width] < 1n) \
.    ab MN: Left margin notes width too small (<1n).
.
.  ie \B'\\$2' \{\
.    nr MN-right-width (n;\\$2)
.    nr MN-right-start (\\n[.o] + \\n[.l] + \\n[MN-sep])
.  \}
.  el \{\
.    nr MN-right-width \\n[MN-left-width]
.    nr MN-right-start (\\n[.o] + \\n[.l] + \\n[MN-sep])
.  \}
.
.  ie \A'\\$4' \
.    ds MN-font \\$4
.  el \
.    ds MN-font
.
.  ie \B'\\$5' \
.    nr MN-size (z;\\$5)
.  el \
.    nr MN-size 0
.
.  ie \B'\\$6' \
.    nr MN-spacing (p;\\$6)
.  el \
.    nr MN-spacing 0
.
.  \" Initialize environments.
.  ev MN-env
.  if \A'\\*[MN-font]' \
.    ft \\*[MN-font]
.  if \\n[MN-size] \
.    ps \\n[MN-size]u
'  in 0
'  nf
.  ev
.
.  ev MNbottom-left-env
.  if \\n[MN-spacing] \
.    vs \\n[MN-spacing]u
.  ll \\n[MN-left-width]u
.  ad \\*[MN-left-ad]
.  ev
.
.  ev MNbottom-right-env
.  if \\n[MN-spacing] \
.    vs \\n[MN-spacing]u
.  ll \\n[MN-right-width]u
.  ad \\*[MN-right-ad]
.  ev
.
.  nr MN-active 0
..
.
.\" EOF