voronoi.find radius? about d3-delaunay

[Fil]

The third argument is currently i, a starting node (default: 0). It helps speed up the search a bit when you start close to the solution (e.g. when you track a mouse's movements).

In d3-voronoi this is an internal value, that is updated after each search. I can't think of a use-case where it would be useful to have it in the API.

[martgnz]

My doubt was in regards implementing something like your block but with a distance-limited interaction. Using d3-voronoi you can just a third argument for the radius.

How would you do something like that with this library? For example, by passing a number close to the current index?

[Fil]

You can always check the distance between your point and the site found, something like (pseudocode):

v.find_with_radius = function(x,y, radius) {
  n = v.find(x,y);
  if (n !== null && distance(site[n], [x,y]) < radius) return n;
}

But I wonder if it should not be put into the API in lieu of [site]. @mbostock we can prepare a PR if you agree with this change.

[mbostock]

The radius (distance) test happens after finding the closest site; it doesn’t optimize the search. So, you should perform your radius test after calling find, as @Fil suggests.

The reason that find takes a starting index is that I don’t want find to mutate the internal state of the delaunay instance (as d3-voronoi does). By keeping the internal state immutable, you have greater flexibility in employing your search optimizations.