How to set a global width for Figures (non generated)?

[kompre]

Description

Hello,

Is there a way to define the max width for figures non generated by code as a global option?

For the generated content there is a fig-width I can define, but it doesn't seems to affect images I insert in the document by myself.

Let's say I want the images to be 75% of the linewidth; I can always do this:

![](img/12354.png){width="75%"}

but this needs to be applied to each image in the document, and also if later I want to change the value (e.g. 80%), I would need to change for each image.

What I would like to do is set a global option in the yaml section, easily modifiable, to act as the default width for all the figures in the document, unless otherwise specified at the local level like in the above example.

This should work both for html and pdf output (probably others too).

I am doing a images report, which contains a lot of figures, so being able to set a global width for the whole documents is quite handy, also because I can then regulate the width to have at least 2 figures per page in the pdf output.

[mcanouil]

Could you share a small self-contained "working" (reproducible) example to work with, i.e., a complete Quarto document or a Git repository? Thanks.

You can share a Quarto document using the following syntax, i.e., using more backticks than you have in your document (usually four ````).

````qmd
---
title: "Reproducible Quarto Document"
format: html
---

This is a reproducible Quarto document using `format: html`.
It is written in Markdown and contains embedded R code.
When you run the code, it will produce a plot.

```{r}
plot(cars)
```

The end.
````

[cderv]

For the generated content there is a fig-width I can define, but it doesn't seems to affect images I insert in the document by myself.

fig-width only works for figures generated by computations as we document at https://quarto.org/docs/reference/formats/html.html#figures

You need to apply attributes on figures individually using Markdown syntax as explained in https://quarto.org/docs/authoring/figures.html#figure-sizing

If you want to apply an attributes on all items in a document, you may leverage Lua filters for that as it would allow you to tweak the document programatically (https://quarto.org/docs/extensions/filters.html)

You would target for example all Image element, and add a width attributes to it. It may work.

Otherwise, know that you could do that globally with other tech. For example if you target HTML output, you could use CSS to change size of all <img> or <figure>

Anyhow, you can't do that using a Quarto option for now.

[mcanouil]

FYI, a quick and dirty JavaScript script:

---
include-in-header:
  - text: |
      <script type="text/javascript">
        window.addEventListener('load', function() {
          const figures = document.querySelectorAll('figure');
          const images = document.querySelectorAll('img');

          figures.forEach(figure => {
            figure.style.width = '75%';
          });

          images.forEach(image => {
            image.style.width = '75%';
          });
        });
      </script>
---

![Logo](https://quarto.org/quarto.png)

[kompre]

Thanks, that useful to know.

To achieve this for the pdf output I've used the include-in-header option like so (it works):

format: 
    pdf:
        include-in-header:
            text: \setkeys{Gin}{width=0.75\linewidth}

I would say though that the fig- keys family could be ambiguous because while some keys like fig-width apply only to generated graphics, others like fig-align apply to all of them.

[mcanouil]

Maybe a little, although having fig-width behaved globally would cause headaches as small images would be upscale leading to poor document quality, whilst fig-align will be harmless on any type of figures.