That gives more background, so we changed the URL to that from https://www.clicktorelease.com/code/bumpy-metaballs/. People who are interested should look at both.

I was confused at first, because the authors are different for these two things.

The current link, fake and cheap metaballs, references the original bumpy metaballs, but only to compare the fast-but-fake version to a slow and complete version.

I didn't realize that. So what's the best URL?

I can't comment on that directly, except to say that both are very interesting and that I enjoyed the blog post more.

One is a beautiful demonstration of metaballs, and the other is a technical description of how to get a similar result without the same cost.

I guess ideally they would have separate threads, but that horse has probably bolted. HN doesn't really have the capability to have a post that says: here are a collection of interesting posts by different people about this interesting subject, beyond the comments like we have here or a self-post with some discussion. That's probably ok.