The plot_fretboard() function can be used to create
general fretboard diagrams directly in R using ggplot and
plot_chord() specifically produces single chord diagrams,
but this vignette shows how to create a standalone chord chart using
LilyPond. Instead of using tab() to render a score to pdf
that may contain a chord chart at the top of the first page, you can use
render_chordchart(). This function creates the necessary
LilyPond file and sends it to LilyPond for final rendering.
Prepare chords
For consistency, render_chordchart() takes chord input
in the same way that score() does, as a named character
vector. The chords and their names are in the same format.
Filter the guitarChords dataset down to chords:
- whose root note is either C or F
- the chords is either a 7th, major 7th, or minor 7th
- the chords do not contain sharps
- and the fret number of the root note is no higher than 12
library(dplyr)
chords <- filter(
guitarChords,
root %in% c("c", "f") &
id %in% c("7", "M7", "m7") &
!grepl("#", notes) & root_fret <= 12
) |>
arrange(root, id)
chords <- setNames(chords$fretboard, chords$lp_name)
head(chords)#> c:7 c:7 c:7 c:7
#> "x;3;2;3;1;x;" "x;3;5;3;5;3;" "x;3;2;3;1;3;" "8;10;8;9;8;8;"
#> c:7 c':7
#> "8;x;8;9;8;x;" "x;x;10;9;11;8;"Render chord chart
The filtering above results in 41 chords. The size of the fretboard
diagrams is increased below with size = 2. Like
lilypond() and the render_* functions that
wrap around it for rendering music scores,
render_chordchart() also takes the header and
paper named list arguments. Once the named chord vector is
ready, rendering the chord chart is as simple as the following.
hdr <- list(
title = "Dominant 7th, major 7th and minor 7th chords",
subtitle = "C and F root"
)
render_chordchart(chords, "out.png", 2, hdr, list(textheight = 175))
The chord chart template must be kept to one page.