It's probably generally faster if you just bulk add points once you're in an interior quad, right? As at https://observablehq.com/@bmschmidt/quadtree-brush-optimization

I think you're right! (But I disagree on the choice of pink 😅)

Wouldn't this be easier if quadtree.visit accepted a starting node? as in https://observablehq.com/d/312fcfaca223e27f

I’m also wondering if quads should be iterable over the contained data.

Yes that would be rad. Some working code based on the previous visit(callback, startNode), to test the API: node[Symbol.iterator] = function*() { const nodes = []; visit.apply(quadtree, [ node => void (node.data && nodes.push(node)), node ]); yield* nodes; }; Usage: > for (const { data } of node) data.immediate = true; (the actual implementation would not store the nodes but yield them immediately)

Here’s a prototype: https://observablehq.com/d/526b5aaee6bbcf5b

Suggest to add ISC License please. Thanks!