@ This is a demonstration file showing how to draw a squiggly line vertically
@ through a system, with a bit of white space on either side, in order to 
@ indicate that two bars are not consecutive. It is easiest to position it
@ by reference to a bar line (which gets wiped out). The drawing function
@ must be called from the bottom stave of the system.

@ Philip Hazel, March 1997

heading ""


draw squiggle
  systemdepth 19 add /h exch def      @ h is the total height including the top system 
                                      @ plus extra to cover the width of the top
                                      @ the and bottom stave lines.
  /w 12 def                           @ w is width of white space required.
   
  w 2 div neg -2 moveto 0 h rlineto   @ Define rectangle to whitewash.
  w 0 rlineto
  0 h neg rlineto w neg 0 rlineto       
  1 setgray fill                      @ Whitewash it.
  
  3 -3 moveto                         @ Squiggle prints 3 points to the left,
                                      @ so move it 3 points right to print at
                                      @ our origin, and start it a bit below.
  h 2 add 4 div 1 add                 @ Compute number to print (each is 4 pts high).
  { "\*145\"/c show 0 4 rmoveto }     @ Print the squiggly line by repeated printing;
  repeat                              @ the /c prevents the current point moving
                                      @ automatically because if that is done, rounding
                                      @ errors build up and the line ends up too short,
                                      @ so instead we explicitly advance 4 points each time.  
enddraw


[stave 1 treble 1]
gggg | gggg ||
[endstave]

[stave 2 bass 0]
gggg [space 4 overdraw squiggle] | [space 8] gggg ||
[endstave]


[newmovement]
heading "Just to prove it works for any system"

[stave 1 treble 1]
gggg | gggg ||
[endstave]

[stave 2 treble 1]
gggg | gggg ||
[endstave]

[stave 3 alto 1]
gggg | gggg ||
[endstave]

[stave 4 bass 0]
gggg [space 4 overdraw squiggle] | [space 8] gggg ||
[endstave]