The inspiration behind this project is largely from John Nelson’s firefly cartography blog posts and maps, and Jonni Walker's cool Fires on Federal Land map on Tableau Public. The motivation to actually do it and write it up, however, was seeing Kent Marten eyes light up last week when I said the magic words: ‘firefly map.’
So…let me introduce a new Tableau point symbol set that I’ve created to make glow-y, firefly-esque maps easier to make in Tableau.
If you want to just jump to making some maps, go ahead and just grab the point symbol sets that you can drop straight into My Tableau Repository/Shapes. There are two folders of data – Firefly and Firefly_Sparkle (think of these as the official Kent Marten Firefly Sparkles™ because Kent, and I’m sure others, deserve extra sparkly symbols for mapping). These are not subtle mapping styles, so why not go the extra mile and add some weird sparkly bling? And, actually, these might be pretty cool shapes to use for a solar system map...
If you want to know how I made these styles so that you can make your own or want edit the styles to meet your special mappy needs, read on.
What is a ‘firefly’ map?
The best, detailed, description comes from John Nelson’s blog post on the topic (Firefly Cartography), so I won't go into a lot of detail. The short story is that for this type of map we want:
- Dark base map
- Bright, glow-y symbols
The contrasts between base map and the high-contrast, bright symbols draws the reader’s eye (because it looks really awesome)!
When is this type of symbol appropriate?
These symbols are more for display / communication than for data exploration. I think of them mostly as eye catching bling to liven up your map. They will make your dashboard look way hipper than you ever imagined.
How do you use these symbols in Tableau?
As of now we don’t have a way to add a transparent gradient colored halo around point symbols natively, so my work around was to create a set of point shapes in bright colors that can be used to symbolize your map data.
Because each of these are little .png graphics, you will use them on the shape shelf instead of the color shelf.
Once you download the zipped set of shapes that I have attached to this post (FireflyTableau.zip), unzip them, and move the folders of shapes in your Tableau Repository folder you should be good to go. Here is where you can find the folder on a Windows machine. I have no clue how Macs work or where you’ll find the folder, but I’m sure a search can unearth it (or someone with a Mac will just send me a screen capture of where My Tableau Repository lives...):
Open up Tableau, drop some point data on your map.
Change the base map to the dark style and remove most of the layers – you want a nice, clean, dark base map with minimal clutter so your points can shine.
Change the mark type for your map to ‘Shape’
Click on the Shape shelf to update the symbol used and in the Shape editor, select the folder with the symbols you want (Firefly or Firefly Sparkle):
Assign the symbols to your points.
Resize on the map until they look awesome.
If you didn't see the symbols showing up as an option, try hitting the Reload Shapes button.
If that doesn’t work, check that you dropped the folders in the right place in My Tableau Repository.
If that still doesn’t work, check if you have a My Tableau Repository (Beta) folder, and drop the shapes there…because you may be Beta testing and want the symbols to be usable in your Beta version.
Additional styling suggestion: Color + the glow-y symbols (and maybe Size if you want to get all super fancy).
You can also put color and/or size on top of the point symbols. With color, the bright white center will be replaced with color, but it is still pretty cool. Here is what they look like with the “Jewel Bright” colors assigned to the shapes:
How do you make your own?
Maybe these aren’t quite what you needed, so you want to fix up your own set of colors or shapes or change the gradient or…. I’ve attached my Adobe Illustrator file to use as a starter. The way that I approached the problem is to pick some nice, bright colors and use a radial gradient with transparency to add a nice glow.
There are probably many other ways to tackle this problem, but hopefully this information has given you some good ideas on how to get started with Firefly-style mapping in Tableau.