Editing Customizing the chord grid style

Custom divisions of chord squares can be defined through the <code>measure-division-lines-alist</code> and <code>measure-division-chord-placement-alist</code> properties of <code>ChordSquare</code>. These are both alists. Their keys are measure divisions, namely lists which give the fraction of the measure that each chord (or rest, or skip) represents. More precisely, a measure division alist is made of positive, exact numbers adding up to 1, for example: <code>'(1/2 1/4 1/4)</code>. The exactness requirement means that, e.g., <code>1/2</code> is valid but not <code>0.5</code>.

The values in <code>measure-division-lines-alist</code> are lists of lines, which are represented as <code>(</code><code>x1</code><code> </code><code>y1</code><code> </code><code>x2</code><code> </code><code>y2</code><code>)</code>. The line starts at the point <code>(</code><code>x1</code><code> . </code><code>y1</code><code>)</code> and ends at <code>(</code><code>x2</code><code> . </code><code>y2</code><code>)</code>. Coordinates are expressed in the [-1, 1] scale relative to the extent of the square.

The values in <code>measure-division-chord-placement-alist</code> are lists of <code>(</code><code>x</code><code> . </code><code>y</code><code>)</code> pairs giving the placement of the respective chords.

This example defines a peculiar chord grid style that has a rule for measures divided in three equal parts.

<lilypond version="2.24.0">
\paper {
  line-width = 10\cm
  ragged-right = ##f
}

\new ChordGrid \with {
  \override ChordSquare.measure-division-lines-alist =
    #'(((1) . ())
       ((1/3 1/3 1/3) . ((-1 -0.4 0 1) (0 -1 1 0.4))))
  \override ChordSquare.measure-division-chord-placement-alist =
    #'(((1) . ((0 . 0)))
       ((1/3 1/3 1/3) . ((-0.7 . 0.5) (0 . 0) (0.7 . -0.5))))
}
\chordmode {
  \time 3/4
  c2.
  c4 c4 c4
}
</lilypond>

[[Category:Chords]]
[[Category:Included in the official documentation]]