Themes

[mkfreeman]

To support different styles, we could create a set of plot themes (e.g., dark, light, etc.). As a comparison, the ggthemes package has default styles to emulate popular styles like the Wallstreet Journal, FiveThirtyEight, etc.

Perhaps a simple approach would be to define a set of styles in Plot.themes that could be set as the style property in a Plot:

Plot.plot({
    style: Plot.themes.dark
})

Where Plot.themes.dark has a set of key/value pairs describing the style: {background: "black", color: "white",...}

[Fil]

related: #6 #7 #114 #253 #397 #662

[awiederkehr]

Would love to help work on this however I can!

[mbostock]

The new axis mark #1197 will help with this, for example you could have a ggplot2 theme #1197 (comment).

[Fil]

Also relevant: https://observablehq.com/@observablehq/custom-plot-themes

[Fil]

Here's a handy response from Mike on the user forum:
https://talk.observablehq.com/t/set-global-plot-defaults-for-observable-plot/7797/3

[martindaniel4]

As a Plot user, that feature would be very useful! Here is also another R package that was relevant to style graphs from a former Airbnb DS - https://github.com/ricardo-bion/ggtech

[Fil]

Textures #903

[tophtucker]

I like Mike’s nice style: Plot.themes.dark suggestion. And it could be prototyped as an ongoing notebook.

It gets trickier when you want to set a default theme across many plots. One can also imagine wanting to set default categorical/sequential/diverging color schemes, etc.

Maybe there could be something like

Plot.defaults({
  style: Plot.themes.dark,
  color: {scheme: {sequential: "blues"}}
})

which would return a new instance of Plot with those defaults? There’d be various difficulties. What’s that object syntax? (Note that I abused the color scheme option.) To name your version Plot in a notebook, would you have to do something like Plot = (await require("@observablehq/plot")).defaults({style: Plot.themes.dark}), or could you take advantage of the built-in Plot?

• https://ggplot2.tidyverse.org/reference/theme_get.html
• https://vega.github.io/vega-lite/docs/config.html
• For the Observable context, also related to the idea of custom stdlibs

[mbostock]

Yes, exactly Toph. On Observable, my hope is that you can configure Plot for your workspace and it automatically applies the theme to notebooks in your workspace without you having to edit them. And likewise in vanilla JavaScript, you could call export default Plot.defaults(…) or whatever and import that instead of Plot.