Highlight elements on table in revealJS Quarto

Question

I have a table in a revealjs Quarto slide. I would like to .fade-in and highlight a value of the table. For example, I would like to highlight the value 3.2 of Sepal.Width in the example below:

---
title: "Highlight elements on table"
format: revealjs
---

## Slide

I would like to fade-in a highlight (color) a piece of text.

```{r}
library(knitr)
kable(head(iris))
```

Output:

Ideally it would look like something like this (created in paint):

As @Julian already suggested, we may use the roughnotation extension, but this can only highlight words in your slide and not anything you want on a slide. So I was wondering if anyone knows how to highlight a value like in the example above in revealjs Quarto?

Answer 1

you can restore the highlighted drawings after you have highlighted things on the revealjs slides.

• Suppose, at first render the following document,

  ---
  title: "Using Chalkboard"
  format: 
    revealjs:
      chalkboard: true
  ---
  
  ## Quarto
  
  Quarto enables you to weave together content and executable code into a finished presentation.
  
  

• And then highlight lines as you want.

• Once you are done highlighting, press D key to download the drawings in a JSON file.

• Now you can refer to this JSON file via the src option under chalkboard key to get those previously done highlights every time you render the document.

  ---
  title: "Using Chalkboard"
  format: 
    revealjs:
      chalkboard: 
        src: chalkboard.json
  ---
  
  ## Quarto
  
  Quarto enables you to weave together content and executable code into a finished presentation.