collision of special notehead and accidental

[takumi ikeda]

When using special notehead, accidental and notehead collide to some specific
notes. What should I do in order to avoid this using Scheme?

\version "2.14.2"

triBk =
#(ly:make-stencil 
        (list 'embedded-ps
        "gsave
        currentpoint translate
        newpath
        -.1675 .5 moveto
        .65625 -.5 lineto
        1.5 .5 lineto
        closepath
        fill
        grestore" )
        (cons -.1875 1.5)
        (cons -.5 .5)
)

triWt =
#(ly:make-stencil 
        (list 'embedded-ps
        "gsave
        currentpoint translate
        newpath
        -.0775 .43 moveto
        .65625 -.43 lineto
        1.39 .43 lineto
        closepath
        0.1 setlinewidth
        stroke
        grestore" )
        (cons -.1875 1.5)
        (cons -.5 .5)
)

#(define (stencil-notehead grob)
        (if (> 2 (ly:grob-property grob 'duration-log))
        triWt triBk
        )
)

upStem          = #'(1 . .9)
downStem        = #'(1 . -1)

#(define (pitch-to-stem stemdir)
        (if (= UP stemdir) upStem downStem)
)

#(define (notehead-get-notecolumn nhgrob)
        (ly:grob-parent nhgrob X))

#(define (notehead-get-stem nhgrob)
        (let ((notecolumn (notehead-get-notecolumn nhgrob)))
                (ly:grob-object notecolumn 'stem)))

#(define (stem-adjuster nhgrob)
        (pitch-to-stem
                (ly:grob-property (notehead-get-stem nhgrob) 'direction) ))


notes = \relative c' {
        c2 cis d dis e f fis g gis a ais b
        c cis d dis e f fis g gis a ais b
        c4 b bes a aes g ges f e ees d des
        c b bes a aes g ges f e ees d des
}


\new Staff 
{
        \override NoteHead #'stencil = #stencil-notehead
        \override NoteHead #'stem-attachment = #stem-adjuster
        <<
                \notes 
        >>
}