How to generate all equations as images in Word format

[Pakillo]

Description

What is the best/easiest way to generate all equations within a Quarto document as images when rendering in Word (docx) format? We want to avoid them being formatted as Microsoft equations, just want plain images.

I found this old thread (https://forum.posit.co/t/rendering-equations-as-images-for-microsoft-output/13862/6) and wondered if there are new ways to do so nowadays. Is there a Quarto option to render all equations as images? Maybe an R package?

Thank you very much in advance

[mcanouil]

I would say to write a Lua filter that:

1. process equations
2. use some third party tool to make them as image ("screenshot")
3. replace equation with image

Something like:

local function math_to_image(math_node)
  if math_node.mathtype ~= 'DisplayMath' then
    return math_node
  end

  local tex_content = math_node.text
  if not tex_content or tex_content == '' then
    return math_node
  end

  -- Generate a unique filename based on the equation content
  local hash = pandoc.sha256(tex_content)
  local image_path = 'math-images/' .. hash .. '.png'

  -- TODO: Implement actual equation rendering

  -- For now, return an Image node pointing to the generated path
  return pandoc.Image(
    { pandoc.Str('LaTeX Equation') },
    image_path,
    'fig:equation',
    {
      ['data-equation'] = tex_content,
      class = 'math-equation-image'
    }
  )
end

return {
  {
    Math = math_to_image
  }
}

[mcanouil]

The following is not at all production-ready and should be used with caution, as it can be broken at any moments. It's only an experiment.
Here is one attempt at using Typst to transform some object (here equations) into images and reuse those images.

• https://github.com/mcanouil/quarto-issues-experiments/tree/main/test-math-to-image-typst

(cc. @cderv FYI, one of my experiment that lead to the PR about exposing Typst)

[cderv]

I though he easiest way would be to leverage the math-method provided by Pandoc which is leveraged in Quarto, but it does not work yet for other than HTML:

• Make --webtex work with all formats jgm/pandoc#7772

(webtex being a service that takes a TeX equation and returns an image. Example of deployed service: https://latex.codecogs.com/)

Other ways to not go through Lua are to leverage the computation engine also.

For example, in knitr ecosystem there is:

• https://yonicd.github.io/texPreview/ that allows to have cells with LaTeX math and output an image. They have a custom engine.
• https://christophertkenny.com/typr/ that allows to have cells with typst and output as image. No custom engine yet.

This is the same idea as with Lua filter but using R code. Probably there is equivalent in Python ecosystem.

We want to avoid them being formatted as Microsoft equations, just want plain images.

Essentially, you need to devise your own solution for the conversion. If you go Lua filter road, it can become a Quarto extension, independant of engine.

[Pakillo]

Thank you both! I'll investigate the strategies you have proposed

Cheers!