terminalgraphics

An R-package for graphical output in terminals. Currently supports terminals that support the Terminal Graphics Protocol and terminals that support Sixel. It implements a graphical device that will output into the terminal and also some functions for retrieving information from the terminal such as the colour scheme used, the dimensions of the terminal and function for displaying png images and image matrices.

Example code

Set the tgp (Terminal Graphics Protocol) device as the standard device and instruct the package to use the terminal colors (only supported currently in Kitty):

options(device = terminalgraphics::tgp, term_col = TRUE)

For example, one could use the following lines in ~/.Rprofile to set the the tgp device as the default device.

if (interactive() && terminalgraphics::has_tgp_support()) {
  options(device = terminalgraphics::tgp, term_col = TRUE)
}

or for Sixel support:

if (interactive() && terminalgraphics::has_tgp_support()) {
  options(device = terminalgraphics::sixel)
}

Creating a plot like, for example:

{
  data(iris)
  plot(iris$Sepal.Width, iris$Sepal.Length, 
    col = term_palette()[iris$Species], 
    pch = 20)
  grid(lty = 2)
  legend("topright", legend = levels(iris$Species), 
    col = term_palette()[1:3], pch = 20)
}

Results in:

By default it will match the colours of the plot to those used of the theme used in the terminal (currently the theme can only be determined for Kitty).

Other functions are:

png2terminal, png2tgp, png2sixel : display a png file in the terminal.

raster2terminal, raster2tgp, raster2sixel : display image raster in the terminal.

term_dim, term_width, term_height : Get the dimensions of the terminal (in pixels and number rows and columns).

term_palette : get a palette based on the colours used in the current theme.

kitty_foreground and kitty_background : get the foreground and background colours of the current theme.

has_tgp_support : determine if the terminal supports the Terminal Graphics Protocol.

has_sixel_support : determine if the terminal supports Sixel.

is_kitty : is R running in a Kitty terminal.

Tips

Every time the contents of the graphics device change after evaluating an expression, a new version of the plot is shown in the terminal. Therefore, the following two lines will result in two plots in the terminal:

plot(rnorm(200))
abline(h = 0)

If you want only one plot to appear in the terminal, you should combine the lines into one expression:

{ 
  plot(rnorm(200))
  abline(h = 0)
}

The size and resolution of the plot can be changed using arguments of tgp and sixel:

tgp(width = 1000, height = 500)
plot(rnorm(200))

It is also possible to set some of these using options:

options(device = terminalgraphics::tgp, term_width = 1000, term_height = 500, 
  term_res = 150, term_col = TRUE)

Note that these options are used for new devices. Therefore, when there is already a device open, you should call tgp/sixel to open a new device or close open devices using dev.off before starting a new plot.