\version "2.19.15"
% -------------------------------------------------------------------------------------------------
% include function file instrument_ranges.ly
% usuage include --> \include "./ranges/instrument_ranges.ly"
% usuage call -->       \naturalizeInstrumentRange "instrument" music
% this function will confine all pitches to the individual instruments range
% Note the ranges refer to music transposed for each instrument not the true pitches.
% use % for comment outside scheme function -  use ; inside scheme functions
% -------------------------------------------------------------------------------------------------

#(define (naturalize-instrument-range p instrument ) 
    (let ((o (ly:pitch-octave p))
            (a (* 4 (ly:pitch-alteration p)))
            (n (ly:pitch-notename p)))

            (define op (+ (+ (+ (* 14 o) ) (* n 2) ) (/ a 2)))

            (cond
 ;; clarinet range e to f'  -1 2 0  to 1 3 0  (-10 to 34)

                ((equal? instrument "clarinet" )
                    (if   (< op -10)  (begin (set! o (+ o 1))))
                    (if  ( > op 34)   (begin (set! o (- o 1 ))))
                )
; bass clarinet range eb to f'  -1 1 2  (-1 2 -2)  to 1 3 0 (-11 to 34)

                ((equal? instrument "bass clarinet eb" )
                    (if   (< op -11)  (begin (set! o (+ o 1))) )
                    (if  ( > op 34)  (begin (set! o (- o 1))) )
                )
; bass clarinet range c to f'  -1 1 2  (-1 2 -2)  to 1 3 0 (-14 to 34)

                ((equal? instrument "bass clarinet c" )
                   (if (< op -14)  (begin (set! o (+ o 1))))
                  (if  ( > op 34)  (begin (set! o (- o 1))))
                )
;; flute range c to f'  0 0 0   to 1 3 0  (0 to 34)

                ((equal? instrument "flute")
                  (if   (< op 0)    (begin (set! o (+ o 1))) )
                  (if  ( > op 34)  (begin (set! o (- o 1))) )
                ) 
;; alto range c to f'  1 0 0   to 1 3 0

                ((equal? instrument "alto")
                 (if   (< op 0)  (begin (set! o (+ o 1))) )
                 (if  ( > op 34)  (begin (set! o (- o 1))) )
                )
            )

            (ly:make-pitch o n (/ a 4)) 

    )
 )
 
% -------------------------------------------------------------------------------------------------
% a variable for the notehaed color on pitch change
% -------------------------------------------------------------------------------------------------

my-color = #(x11-color 'red)
 
% -------------------------------------------------------------------------------------------------
% this function rebuilds the music object optionally changing pitch and notehead color
% -------------------------------------------------------------------------------------------------
#(define (instrumentrange music instrument ) 
               (  ly:music? string? ) 
; extract the various portions of the music object
   (let ((es (ly:music-property music 'elements))      
           (e   (ly:music-property music 'element)) 
           (p   (ly:music-property music 'pitch)))
 
; rebuild any 'elements unchanged
        (if (pair? es)
            (ly:music-set-property! music 'elements
                 (map (lambda (x) (instrumentrange x instrument)) es)
            )
        )  

; rebuild any 'element unchanged
        (if (ly:music? e) (ly:music-set-property! music 'element
             (instrumentrange e instrument ))
        )

;rebuild the pitch and if a changed pitch add the color tweak
        (if (ly:pitch? p)
            (let ((new-pitch (naturalize-instrument-range p instrument)))
                   (ly:music-set-property! music 'pitch new-pitch)
                   (if (and (not (equal? p new-pitch)) (color? my-color))
                        (ly:music-set-property! music 'tweaks
                            (acons
                                'color my-color
                                (ly:music-property music 'tweaks)
                           )
                      )
                   )
             )
        )
     music
     )
   )
 
% -------------------------------------------------------------------------------------------------
% the Lily file calling function \naturalizeInstrumentRange  "clarinet"  followed by sequential music
% -------------------------------------------------------------------------------------------------
naturalizeInstrumentRange =
#(define-music-function (parser location  instrument m ) 
  ( string? ly:music? )  
  (instrumentrange m instrument ))
 
\score {
  \naturalizeInstrumentRange "alto"
  \new Staff \relative c' {
   c,,8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
  c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
    
  }
}
\score {
 \new Staff \relative c' {
    c,,8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
   c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
  c8  cis des d dis ees e eis fes f fis ges g gis aes a ais bes b bis ces
    
  }
}