Prettier R Graphs and Documents

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# Prettier R Graphs and Documents
## with <code>showtext</code> + <code>prettydoc</code>
### Yixuan Qiu
### Greater Cleveland R Group
### 2020/10/28

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# Get Started

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# A Typical Data Visualization

.center[![](images/horror.png)]

???

Code derived from http://gradientdescending.com/adding-custom-fonts-to-ggplot-in-r/

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# Let's Change the Fonts

.center[![](images/horror-showtext.png)]

http://gradientdescending.com/adding-custom-fonts-to-ggplot-in-r/

---

# Why Changing Fonts was Hard in R

- Device dependent

- `windowsFonts()` for `windows()` devices
  - `X11Fonts()` for `X11()` devices
  - `quartzFonts()` for `quartz()` devices
  - `postscriptFonts()`, `pdfFonts()`, etc.

- Many difficulties for the PDF device

- Limited choices, `names(pdfFonts())`
  - Does not support TTF/OTF fonts
  - Needs to embed fonts using Ghostscript

- Ambiguity of font names

- Reproducibility

- Other people need to install the same fonts to use your code

---

# Hello, World

```r
library(showtext)
# download.file("http://simonsoftware.se/other/xkcd.ttf",
#               "fonts/xkcd.ttf", mode = "wb")
*font_add(family = "xkcd", regular = "fonts/xkcd.ttf")
*font_add_google(name = "Turret Road")
*showtext_auto()

pie(c(0.9, 0.1), col = c("#F8766D", "#00BFC4"), radius = 1, border = NA,
    labels = c("Test Internet connection", "Find useful information"),
    family = "xkcd", cex = 2)
title("When you visit google.com", family = "Turret Road", cex.main = 2.5)
```

???

https://www.pinterest.com/pin/127719339412665422/

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# What's Happening Here?

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# Core Functions

- `font_add()`: Register a font file

- `family`: The family name you want to use in R
  - `regular`: Font file for the "regular" font face
  - `bold`: Font file for the "bold" font face
  - ...

- `font_add_google()`: Register a font from [Google Fonts](https://fonts.google.com/)

- `name`: The font name in the Google Fonts database
  - `family`: The family name you want to use in R

- `showtext_auto()`: Enable `showtext`. **That's it!**

- `showtext_opts(dpi = 200)`: If you need to adjust the DPI

---

# How showtext works

- .warning[Caveat: text is no longer searchable in `showtext`-enabled plots]

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# Fantastic Fonts

### and Where to Find Them

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# Font Resources (for free)

- Explore your local machine using `font_files()`

- Google Fonts (https://fonts.google.com/)

- Font Squirrel (https://www.fontsquirrel.com/)

- DaFont (https://www.dafont.com/)

- 1001 Fonts (https://www.1001fonts.com/)

- Many others

---

# Useful Utilities

- `font_families()`: List registered font families

```
## [1] "sans"         "serif"        "mono"         "wqy-microhei" "Open Sans"   
## [6] "xkcd"         "Turret Road"
```

- `font_files()`: List font files that are available in the system

```
##               path         file       family        face      version
## 1 C:/Windows/Fonts  AGENCYB.TTF    Agency FB        Bold Version 1.01
## 2 C:/Windows/Fonts  AGENCYR.TTF    Agency FB     Regular Version 1.01
## 3 C:/Windows/Fonts    ALGER.TTF     Algerian     Regular Version 1.57
## 4 C:/Windows/Fonts  ANTQUAB.TTF Book Antiqua        Bold Version 2.35
## 5 C:/Windows/Fonts ANTQUABI.TTF Book Antiqua Bold Italic Version 2.35
## 6 C:/Windows/Fonts  ANTQUAI.TTF Book Antiqua      Italic Version 2.35
```

- `font_install()`: Install fonts to the local machine (more details later)

---

# Save Frequently Used Fonts

- Suppose you have a Google font that is used frequently

- You don't want to download it every time you use it

- `showtext` allows you to install it to the `showtextdb` package

```r
opensans = google_fonts("Open Sans")
font_install(opensans)
list.files(system.file("fonts", package = "showtextdb"))
```

```
## [1] "AUTHORS.txt.tar.gz"   "LICENSE_Apache2.txt"  "Open Sans"           
## [4] "wqy-microhei.ttc.zip"
```

```r
font_families()
```

```
## [1] "sans"         "serif"        "mono"         "wqy-microhei" "Open Sans"   
## [6] "xkcd"         "Turret Road"
```

---

# Save Frequently Used Fonts - cont.

- You can put any local fonts under the `fonts` folder of the `showtextdb` package

- They will be automatically loaded by `showtext`

- The directory name is the font family, with `regular.ttf`, `bold.ttf` etc. files inside the directory

```r
list.files(system.file("fonts", "Open Sans", package = "showtextdb"))
```

```
## [1] "bold.ttf"       "bolditalic.ttf" "italic.ttf"     "regular.ttf"
```

- .warning[Warning: The local fonts will be deleted if you upgrade/reinstall
the `showtextdb` package]

---

# Use showtext in R Markdown

- One option does it all: `fig.showtext = TRUE`

``````yaml
---
title: "Title"
author: "Author"
output: html_document
---

```{r setup, include=FALSE}
library(showtext)
font_add_google("Lobster", "lobster")
```

```{r fig.showtext=TRUE}
plot(1, pch = 16, cex = 3)
text(1, 1.1, "A fancy dot", family = "lobster", col = "steelblue", cex = 3)
```
``````

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# .comic[Be Cautious with Fonts!]

- .comic[You probably don't want to use Comic Sans]...

???

https://blog.hitbtc.com/dogecoin-such-wow-cryptocurrency-that-aims-to-help/

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# Showcase

.pull-left[

`emojifont` (https://github.com/GuangchuangYu/emojifont)

![](images/emojifont.png)

]

.pull-right[

`meme` (https://github.com/GuangchuangYu/meme/)

![](images/meme.png)

]

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# Showcase - cont.

`trekfont` (https://github.com/leonawicz/trekfont)

![](images/trekfont.png)

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# Showcase - cont.

`thematic` (https://github.com/rstudio/thematic)

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# Showcase - cont.

`ggcharts` (https://github.com/thomas-neitmann/ggcharts)

.pull-left[

![](images/ggcharts-1.png)

]

.pull-right[

![](images/ggcharts-2.png)

]

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# Other Solutions

- `extrafont`: TTF fonts + PDF device

- `systemfonts`: Provides system native access to the font catalogue, nice combination with the `ragg` graphic device

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# Special Thanks

.pull-left[

- Yihui Xie [@yihui](https://github.com/yihui), who kindly added `showtext` support to his fantastic [knitr](https://yihui.org/knitr/) package

]

.pull-right[

- Carson Sievert [@cpsievert](https://github.com/cpsievert), who gave me numerous bug reports and suggestions, and helped me fix an issue that bothered me for years

]

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# What's Next?

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# Pretty Documents

- Now you have a pretty plot using some fancy fonts

- You also want to include it in a nice-looking document

- The built-in `html_document()` format in the `rmarkdown` package already has a `theme` option to support different styles

- The `prettydoc` package provides more choices

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# Overview of Themes

.pull-left[

Architect

]

.pull-right[

Cayman

]

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# Overview of Themes - cont.

.pull-left[

HPSTR

]

.pull-right[

Tactile

]

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# Overview of Themes - cont.

Leonids

[![](images/leonids.png)](https://cran.r-project.org/web/packages/prettydoc/vignettes/leonids.html)

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# Quick Start

.left27[

Step 1

![](images/step1.png)

]

.right70[

Step 2

![](images/step2.png)

]

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# What's Special about prettydoc?

- Provides more stylish themes if you are bored with the default ones

- Small in size, no Bootstrap or other heavy libraries

- A good choice for package vignettes

- Some unique features

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# Options

- Specify options similar to the default `html_document()` format

```yaml
---
title: "Title"
author: "Author"
output:
  prettydoc::html_pretty:
    theme: cayman
    highlight: github
    toc: true
toc-title: "Table of Contents"
---
```
--

- `themes`: architect, cayman, hpstr, tactile, leonids

- `highlight`: github, vignette, null

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# Offline Math Expressions

- Unique in `prettydoc`

- Option to use the lightweight [KaTeX](https://katex.org/) library to render math expressions

```yaml
---
output:
  prettydoc::html_pretty:
    theme: cayman
    highlight: github
    math: katex
---
```

- Documents can be viewed without Internet connections

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# What's Missing in prettydoc :(

- No float table of contents

- No tabbed sections

- .warning[Help needed!]

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# Other Templates

- `rmdformats` (https://github.com/juba/rmdformats)

- `minidown` (https://github.com/atusy/minidown)

- `tufte` (https://github.com/rstudio/tufte)

- `BiocStyle` (https://github.com/Bioconductor/BiocStyle)

- `markdowntemplates` (https://github.com/hrbrmstr/markdowntemplates)

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background-image: url(images/github.png)
background-size: 128px
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# Links

- `showtext`: https://github.com/yixuan/showtext

- `prettydoc`: https://github.com/yixuan/prettydoc

- Personal website: https://statr.me

- Email: yixuanq@gmail.com

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# Thanks!