Next up, we kept the same data, but added a few interesting things. First, a new section, i.e., continent. And also, another ring, i.e., style of government. For the new ring, we could have let the library pick the right shade of grey, but instead, we overrode the colour with our own hideous choice. We also added some fictitious, comic-book countries (and no, they're not always "accurate"). We also changed the opacity for these fictional countries.

Features to watch out for:

• Sections and rings are linked to data points by reference (an id), not number, which is why introducing new sections or rings does not affect the placement of prior data points.
• Rings can be given colours, overriding the default shade of grey.
• Sections can be, and should be given colours, though if you don't, the library will pick some anodyne colour that is bound to be unsatisfying.
• Data points can be given an opacity between [0, 1], with the default being 1. If you can map another dimension of data to opacity, go for it.
• All features explained so far work as expected in all combinations.

Play around with these widgets to change the layout. View source to see how to configure the JSON object to invoke the library. And when you're ready, move on to the next demo. Or for a refresher, go back to the previous demo. Or click on: Start, Demo 1, Demo 2, Demo 3, Demo 4, Demo 5, Demo 6.