For discussion: Ideas for generating category colors that go beyond our max

[makella]

As we all know, there are times when people want to symbolize more than 10 or 11 categories on their maps.

Here are a few ideas for how we might be able to make this happen:

One CARTOColor palette to support a wider range of colors

• Create a CARTOColor palette with 50 colors (for example) and use if we detect more than 11 categories.
  • In this example, @ramiroaznar used a set of 50 category colors that I had generated using an online tool: https://team.carto.com/u/ramirocartodb/builder/02390d48-d19c-11e6-af17-0ecd1babdde5/embed

CartoCSS Spin

• Take advantage of the CartoCSS spin function. If we could use color functions inside of TurboCARTO we could allow a user to use something like spin.
  • For example, syntax could look something like: marker-fill: ramp([attribute],(#ff0000),spin(0,360),category(20)); Ideally, what would happen here is that we would use the starting color #ff0000 and take the entire spectrum of the color wheel 0,360 and make 20 stops.
  • Alternatively, if someone wanted to limit a particular color range, they could write something like: marker-fill: ramp([attribute],spin(30,120),category(20));

Implement existing online tools

• There are a couple of tools that generate category palettes using smart thinking around perceptual color spaces:
  • https://github.com/medialab/iwanthue
  • https://github.com/connorgr/colorgorical

Other ideas??

cc @saleiva

[makella]

Or the spin syntax is more inline with current implementation if it was like this:

marker-fill: ramp([attribute],spin(#ff0000,5),category(20));

What would happen here is that the starting color would be #ff0000 and we would generate another color in 5 degree increments around the color wheel for 20 categories.

This could be tricky, for distinguishable colors, but I think it would be really neat to try!

here are a couple of examples with longhand CartoCSS:

• for colors that are more similar, using smaller spins:

  

• using larger spin intervals for colors that are less similar:

  

[ramiroaznar]

Totally agree. But on the other hand, it is going to be a conflict when generating legends.