This is a reusable dex.js radar chart composed of treemaps based upon Nadieh Bremer’s example.
The radar chart is sometims called the spider chart. Interestingly, it is a variant of parallel coordinates mapped on to polar coordinates.
In dex.js, legends are a separate component and populated via intra-chart communication. It frees individual chart implementations of the burden of drawing a legend. It also enables us to provide a single, robust and full featured implementation instead of re-implementing the same old thing over and over again for each individual chart. More on this in a later block.