docs/features.dot has a more up-to-date source. The image should be generated when building the documentation, if possible, instead of being static in the repository.

Perhaps some text to note that this is just an approximate and not how shaping is fully done.

Maybe also link to https://prezi.com/view/THNPJGFVDUCWoM20syev/ as well

Perhaps some text to note that this is just an approximate and not how shaping is fully done.

Is it feasible to have it be correct? Failing that, to note where it is not?

Perhaps some text to note that this is just an approximate and not how shaping is fully done.

Is it feasible to have it be correct? Failing that, to note where it is not?

HB individual shapers do a lot of logic. That's not reflected in the graph. Also, just for example, recent versions of HB, to match Windows, apply rclt only if calt feature was NOT found in the font.