FWIW, a “long” time ago, I proposed
[#8048](https://github.com/matplotlib/matplotlib/pull/8048), which was
actually inspired by the example that you cited. However, I did not
manage to pursue the work in order to get significant traction on that
very proposal (which is likely to be a tricky one, as it may induce many
corner-cases that I did not think of…). Unfortunately, I do not expect
to have time resuming on that proposal any time soon.
As Elan wrote, please feel free to contribute on this topic :).