LaTeX to SIXEL

Sixel graphics is well suited to display images on terminals (emulation) like Mintty (Cygwin), mlterm or Xterm. Thanks to Hayaki Saito's libsixel, we can easily convert almost any format to sixel sequences (e.g. img2sixel).

latex2sixel

This simple shell script converts (La)TeX chunks to sixel output by the following composition of tools:

  latex [dvi] --> dvipng [png] --> img2sixel  

Therefore, the requirements to render LaTex chunks to a sixel graphics capable console/terminal are as follows:

• LaTeX distribution
• dvipng (usually already included)
• libsixel (see Install)
• Sixel capable terminal

$ latex2sixel

This is latex2sixel V 1.0.2 (Mon Apr 11 15:59:19 CEST 2022)

Usage: ./latex2sixel [OPTION]... TEXSTRING
Options are chosen to be similar to dvips' options where possible:

  -D #         Output resolution
  -O c         Image offset
  -T c         Image size (also accepts '-T bbox' and '-T tight')

  -bg s        Background color (TeX-style color or 'Transparent')
  -fg s        Foreground color (TeX-style color)

  -h | --help  Help

  # = number   s = string
  c = comma-separated dimension pair (e.g., 3.2in,-32.1cm)

  TEXSTRING is a LaTeX expression betweeen apostrophes (not quotes).
  Examples: '$\alpha$' | '\LaTeX' | 'This is math: $x+y$'.

Required applications: latex, dvipng, img2sixel.
Terminals supporting sixel graphics: xterm -ti vt340, mintty, mlterm.
More info @  https://github.com/saitoha/libsixel

The script is just a skeleton and may be adjusted to your needs.

Installation

Just copy the file(s) in the script directory to a folder in the path, e.g. /usr/local/bin or .local/bin.

Examples

latex2sixel '$-\frac{\hbar^2}{2m}\,\Delta\psi+V\,\psi=E\,\psi$'
latex2sixel \\partial{T}\(\\phi\)=T\(d\\phi\)
latex2sixel '$$\int_{\partial\Omega}\omega=\int_\Omega\,d\omega$$'
latex2sixel '\LaTeX\ is\ cool :)'

latex2sixel '$$\sum_{j=0}^N q^j=\frac{q^{N+1}-1}{q-1}$$'
latex2sixel '$$\forall x\in\mathbb{Z},\exists y\in\mathbb{Z}:x+y=0$$'

Applications

A lot of mathematical software is able to produce TeX output, e.g. computer algebra systems (CAS) like FriCAS (Axiom), Maxima, Reduce, Sage, Sympy and a lot more. Many OO languages like Python or Pure have the capability to render the objects by a special representation field.
Certain applications, however, need a special treatment, that is for instance a preamble or macro definitions which should be prepended to the input. The script fricas2sixel is such an example. When we define the function

sixel(x:TexFormat):Void ==
  cmd:=concat ["system fricas2sixel -bg Black -D 150 -fg Orange '",tex(x).1,"'"]
  systemCommand(cmd)

we can render almost any expression as its LaTex representation in the console:

The function can be included into the startup file (.fricas.input), then the usage is: sixel expression.

Another example is Pure:

For details consult the sample file sixel.pure in the samplefolder.

GnuPlot

GnuPlot is a portable command-line driven graphing utility for Linux, OS/2, MS Windows, OSX, VMS, and many other platforms. It can produce sixel output. It also provides an easy mean to check if your terminal is capable to display sixel output: gnuplot> test

Calibration

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