In dreamRs/gfonts: Offline 'Google' Fonts for 'Markdown' and 'Shiny'

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>", 
  eval = FALSE
)

library(gfonts)

{gfonts} allow you to use a Google font to use it offline in a Shiny application or a R Markdown document. You can download a font via google-webfonts-helper and generate appropriate CSS to use it.

Setup a font to use in your project

In your project directory, use setup_font once to download a font and generate CSS code. For example to use the Roboto font, you can do :

setup_font(
  id = "roboto",
  output_dir = "www",
  variants = "regular"
)

In a Shiny application you can use www/ folder, for R Markdown, create a sub-folder at the same level as your .Rmd file.

setup_font() will create two sub-folders, containing the following files :

www
+-- css
|   \-- roboto.css
\-- fonts
    +-- roboto-v20-latin-regular.eot
    +-- roboto-v20-latin-regular.svg
    +-- roboto-v20-latin-regular.ttf
    +-- roboto-v20-latin-regular.woff
    \-- roboto-v20-latin-regular.woff2

To know all fonts and their ids, you can use get_all_fonts() :

head(get_all_fonts())

Use a font

To use a downloaded font, you can use in your UI or in a chunk :

use_font("roboto", "www/css/roboto.css")

First argument is the id of font downloaded, second is path to CSS file generated.

An other solution in Shiny application is to import the CSS file in a link tag and add a style tag:

fluidPage(

  tags$link(rel = "stylesheet", type = "text/css", href = "css/roboto.css"),
  tags$style("body {font-family: 'Roboto', sans-serif;}")

)

In Markdown, import CSS file in yaml header, and add a CSS chunk :

---
output: 
  html_document:
    css: assets/css/roboto.css
---

```{css}
body {font-family: 'Roboto', sans-serif;}
```

Download a font

If you only want to download a font, you can use:

download_font(
  id = "roboto",
  output_dir = "azerty",
  variants = c("regular", "300italic", "700")
)

Generate CSS

To download CSS code to import a font in HTML, you can use:

generate_css("roboto", "regular", font_dir = "path/to/font")

cat(generate_css("roboto", "regular", font_dir = "path/to/"))

The path must be relative to the one were this code is saved.

dreamRs/gfonts documentation built on Jan. 25, 2023, 7:48 p.m.