Despite the near-mythical power of D3 layouts, they turn out to be nothing more than helpers that turn your data into a collection of coordinates.
After going all-out with these examples, we used almost every trick we've explained so far. We even wrote so much code that we had to make a separate library! With a bit of generalization, some of those functions could be layouts of their own. There's a whole world of community-developed layouts for various types of charts. The
d3-plugins repository on GitHub (https://github.com/d3/d3-plugins) is a good place to start exploring.
You now understand what all the default layouts are up to, and I hope you're already thinking about using them for purposes beyond the original developers' wildest dreams. ...