This is my first post here.
I have made an animated choropleth (with a tooltip) as a visualization for some academic colleagues: https://observablehq.com/@theohonohan/birthright-indicators-2000-2020
A similar map was shared on Twitter a few weeks ago, although I can’t find it now. It had the same performance problems as mine.
Although the animation runs at an acceptable speed when the “Play” button is pressed, if I drag the time slider back and forth, the updates to the map are a bit slow. I suspect that this is because the data is somehow being recomputed for each year (rather than being some SVG rendering problem).
Is there an easy fix for this, perhaps involving some kind of caching/memoization of the data?