radius legends
It's just one possibility among several
(I've based this on mbostock/arrow since it involves quite a few changes in the legends section)
related: https://github.com/observablehq/plot/pull/539 https://github.com/observablehq/plot/pull/432 https://github.com/observablehq/plot/pull/583
todo:
- [ ] fix circular dependency (maybe rewrite as pure d3?)
I've fixed the conflict but I now have a circular dependency which I don't know how to fix. Should I rewrite this legend as "pure d3" rather than using Plot?
As an alternative here's an independent implementation https://observablehq.com/@recifs/a-radius-legend-for-plot-665
See also discussion https://github.com/observablehq/plot/discussions/1106