% Extension for MusiXTeX - Guitar Tablatures
%
% This file contains some macros which extend MusiXTeX with some
% common notations for guitar tablatures. It is recommended that
% you use a 6-line system (assuming a 6-string guitar) and increase
% the space between its staves, e.g.:
%
% \setlines16
% \setsize1\largevalue
\makeatletter

% Clef symbol that displays "TAB" vertically (looks best with
% \smallmusicsize)
\def\tabclefsymbolsmall{\vtop to .75\Interligne{%
  \vss%
  \hbox to 2.5\Interligne{\hss\tinytype\bf T}%
  \vskip -1\Interligne
  \hbox to 2.5\Interligne{\hss\tinytype\bf A}%
  \vskip -1\Interligne
  \hbox to 2.5\Interligne{\hss\tinytype\bf B}}}

% Display guitar string numbers on staves
% 
% Usage: \str{<string>}{<number>}
%   <string>: string number between 1 and 6
%   <number>: any number (or other text) to put onto the string
%             (usually a fret number between 0 and 24)
%
% \str inserts horizontal space after the number (like other
% MusiXTeX notes). To insert a non-spacing string note, use
% \zstr.
\def\strerr{\errmessage{str macro requires a string number from 1--6}}
\def\zstr#1#2{%
  \ifcase#1\relax\strerr
  \or\def\@strnr{-1}%
  \or\def\@strnr{1}%
  \or\def\@strnr{3}%
  \or\def\@strnr{5}%
  \or\def\@strnr{7}%
  \or\def\@strnr{9}%
  \else\strerr
  \fi
  \cchar\@strnr{\tinytype\bf\roffset{.35}{#2}}}
\def\str#1#2{\zstr{#1}{#2}\sk}

% Insert a Palm Mute indicator (P.M.) starting at the current position.
% 
% Usage: \palmmute{<pitch>}{<length>}
%   <pitch>: vertical level at which the palm mute is placed
%   <length>: length of the line in multiples of \noteskip
%
% This will insert a palm mute indicator looking similar to this:
%   P.M.-----------|
% If <length> is sufficiently small, no line will be inserted, just
%   P.M.
\newtoks\@pmstring
\chardef\@pmlinechar=45
\chardef\@pmendchar=21
\newdimen\@pmboxminwd
\@pmboxminwd=2.3em
\def\palmmute{\check@staff
  \n@v\@pmlinechar \n@ii\@pmendchar\global\@pmstring={P.M.}\fi
  \@drawpm}
\def\@drawpm#1#2{\check@staff
  \y@v#2\noteskip%
  \ifnum #2<2
  \zcharnote{#1}{\loff{\hbox\@to\@pmboxminwd{%
    \@pminit}}}%
  \else
  \zcharnote{#1}{\loff{\hbox\@to\y@v{%
    \@pminit\xleaders\hbox{\char\n@v}\hfill\mxsps\char\n@ii}}}%
  \fi\fi}
\def\@pminit{%
  \setbox\w@rkbox\hbox{\tinytype\the\@pmstring}%
  \box\w@rkbox}

% Insert a Hammer On or Pull Off symbol.
%
% Usage: \hammeron{<pitch>}{<offset>}
%        \pulloff{<pitch>}{<offset>}
%  <pitch>: vertical level at which the symbol is placed
%  <offset>: horizontal offset from the current position
%            in note head widths
%
% \hammeron will insert an "H", while \pulloff will insert
% a "P".
\def\hammeron#1#2{%
  \ccharnote{#1}{\tinytype\roffset{#2}{H}}}
\def\pulloff#1#2{%
  \ccharnote{#1}{\tinytype\roffset{#2}{P}}}

% Insert a Natural Harmonics or Artifical Harmonics
% indicator.
%
% Usage: \harmonics{<pitch>}{<offset>}
%        \aharmonics{<pitch>}{<offset>}
%  <pitch>: vertical level at which the symbol is placed
%  <offset>: horizontal offset from the current position
%            in note head widths
%
% \harmonics will insert "Harm.", while \aharmonics will
% insert "A.H.".
\def\harmonics#1#2{%
  \ccharnote{#1}{\tinytype\roffset{#2}{Harm.}}}
\def\aharmonics#1#2{%
  \ccharnote{#1}{\tinytype\roffset{#2}{A.H.}}}

% Insert a bend indicator at the current position.
%
% Usage: \bendhalf{<pitch>}{<textpitch>}{<offset>}
%        \bendfull{<pitch>}{<textpitch>}{<offset>}
%   <pitch>: vertical level at which the lower end of the
%            bend curve is placed
%   <textpitch>: vertical level at which the text is placed
%   <offset>: horizontal offset from the current position
%             in note head widths
%
% \bendhalf uses the text "1/2", while \bendfull uses the
% text "Full".
%
% There are more commands like \Bendhalf, \Bendfull, and
% \Bend, which allow full control over the curve parameters,
% text etc. However, they should rarely be necessary.
\newtoks\@bendslurid
\newtoks\@bendstring
\newtoks\@bendho
\newtoks\@bendvo
\newtoks\@bendht
\newtoks\@bendvt
\newtoks\@bendcur
\newtoks\@bendang
\@bendslurid={14}

\def\@rstbendho{\global\@bendho={2}}
\def\@rstbendvo{\global\@bendvo={2}}
\def\@rstbendht{\global\@bendht={4}}
\def\@rstbendvt{\global\@bendvt={6}}
\def\@rstbendcur{\global\@bendcur={-.4}}
\def\@rstbendang{\global\@bendang={.2}}
\def\@rstbend{\@rstbendho\@rstbendvo\@rstbendht\@rstbendvt\@rstbendcur\@rstbendang}

\def\@setbendstring#1{\global\@bendstring={#1}}
\def\@setbendho#1{\global\@bendho={#1}}
\def\@setbendvo#1{\global\@bendvo={#1}}
\def\@setbendht#1{\global\@bendht={#1}}
\def\@setbendvt#1{\global\@bendvt={#1}}
\def\@setbendcur#1{\global\@bendcur={#1}}
\def\@setbendang#1{\global\@bendang={#1}}

\def\bendhalf{\check@staff
  \@rstbend\@setbendstring{1/2}\fi
  \@drawbend}
\def\Bendhalf#1#2{\check@staff
  \@rstbend\@setbendstring{1/2}%
  \@setbendht{#1}\@setbendvt{#2}\fi
  \@drawbend}
\def\bendfull{\check@staff
  \@rstbend\@setbendstring{Full}\fi
  \@drawbend}
\def\Bendfull#1#2{\check@staff
  \@rstbend\@setbendstring{Full}%
  \@setbendht{#1}\@setbendvt{#2}\fi
  \@drawbend}
\def\Bend#1#2#3#4#5#6#7{\check@staff
  \@rstbend\@setbendstring{#1}%
  \@setbendho{#2}\@setbendvo{#3}\@setbendht{#4}%
  \@setbendvt{#5}\@setbendcur{#6}\@setbendang{#7}\fi
  \@drawbend}
\def\@drawbend#1#2#3{\check@staff
  \roffset{#3}{\iSlur{\the\@bendslurid}{#1}{\the\@bendvo}{\the\@bendho}%
  \tSlur{\the\@bendslurid}{#1}{\the\@bendvt}{\the\@bendht}{\the\@bendcur}{\the\@bendang}%
  \ccharnote{#2}{\tinytype\roffset{\the\@bendho}{\the\@bendstring}}}%
  \fi}

% Insert a slide indicator at the current position.
%
% Usage: \gslide{<pitch>}{<length>}{<slope>}
%        \gslidet{<pitch>}{<length>}{<slope>}{<textpitch>}{<textoffset>}
%        \gSlide{<pitch>}{<voffset>}{<length>}{<slope>}
%        \gSlidet{<pitch>}{<voffset>}{<length>}{<slope>}{<textpitch>}{<textoffset>}
%   <pitch>: vertical level at which the beginning of the
%            line is placed
%   <voffset>: additional vertical offset (for fine-tuning
%              the line position)
%   <length>: length of the line (values smaller than 2
%             may cause weird behavior)
%   <slope>: slope of the line (should be in [-20,20] range)
%   <textpitch>: vertical level at which the text is placed
%   <textoffset>: horizontal offset from the current position
%                 in note head widths for the text
%
% These commands insert a straight line. The text versions
% additionally insert the text "sl." in italics.
\newtoks\@gslidestring
\newtoks\@gslideho
\newtoks\@gslidevp
\newtoks\@gslidevo
\newtoks\@gslidelen
\newtoks\@gslideslp
\newtoks\@gslidestrho
\newtoks\@gslidestrvp

\def\@rstgslideho{\global\@gslideho={1.5}}
\def\@rstgslidevp{\global\@gslidevp={m}}
\def\@rstgslidevo{\global\@gslidevo={0}}
\def\@rstgslidelen{\global\@gslidelen={3}}
\def\@rstgslideslp{\global\@gslideslp={-10}}
\def\@rstgslidestrho{\global\@gslidestrho={1.8}}
\def\@rstgslidestrvp{\global\@gslidestrvp={p}}
\def\@rstgslide{\@rstgslideho\@rstgslidevp\@rstgslidevo\@rstgslidelen\@rstgslideslp\@rstgslidestrho\@rstgslidestrvp}

\def\@setgslidestring#1{\global\@gslidestring={#1}}
\def\@setgslideho#1{\global\@gslideho={#1}}
\def\@setgslidevp#1{\global\@gslidevp={#1}}
\def\@setgslidevo#1{\global\@gslidevo={#1}}
\def\@setgslidelen#1{\global\@gslidelen={#1}}
\def\@setgslideslp#1{\global\@gslideslp={#1}}
\def\@setgslidestrho#1{\global\@gslidestrho={#1}}
\def\@setgslidestrvp#1{\global\@gslidestrvp={#1}}

\def\gslide#1#2#3{\check@staff
  \@rstgslide\@setgslidevp{#1}%
  \@setgslidelen{#2}\@setgslideslp{#3}\fi
  \@drawgslide}
\def\gslidet#1#2#3#4#5{\check@staff
  \@rstgslide\@setgslidevp{#1}%
  \@setgslidelen{#2}\@setgslideslp{#3}%
  \@setgslidestrvp{#4}\@setgslidestrho{#5}\@setgslidestring{sl.}\fi
  \@drawgslide\@drawgslidestr}
\def\gslideT#1#2#3#4#5#6{\check@staff
  \@rstgslide\@setgslidevp{#1}%
  \@setgslidelen{#2}\@setgslideslp{#3}%
  \@setgslidestrvp{#4}\@setgslidestrho{#5}\@setgslidestring{#6}\fi
  \@drawgslide\@drawgslidestr}
\def\gSlide#1#2#3#4{\check@staff
  \@rstgslide\@setgslidevp{#1}\@setgslidevo{#2}%
  \@setgslidelen{#3}\@setgslideslp{#4}\fi
  \@drawgslide}
\def\gSlidet#1#2#3#4#5#6{\check@staff
  \@rstgslide\@setgslidevp{#1}\@setgslidevo{#2}%
  \@setgslidelen{#3}\@setgslideslp{#4}%
  \@setgslidestrvp{#5}\@setgslidestrho{#6}\@setgslidestring{sl.}\fi
  \@drawgslide\@drawgslidestr}
\def\gSlideT#1#2#3#4#5#6#7{\check@staff
  \@rstgslide\@setgslidevp{#1}\@setgslidevo{#2}%
  \@setgslidelen{#3}\@setgslideslp{#4}%
  \@setgslidestrvp{#5}\@setgslidestrho{#6}\@setgslidestring{#7}\fi
  \@drawgslide\@drawgslidestr}
\def\@drawgslide{\check@staff
  \zcharnote{\the\@gslidevp}{\roffset{\the\@gslideho}{\varline{\the\@gslidevo}{\the\@gslidelen\qn@width}{\the\@gslideslp}}}%
  \fi}
\def\@drawgslidestr{\check@staff
  \zcharnote{\the\@gslidestrvp}{\tinytype\it\roffset{\the\@gslidestrho}{\the\@gslidestring}}%
  \fi}

\makeatother