Pressing down more than 4 keys at the same time is unreliable about react-piano

[kevinsqi]

Yeah, this is an open issue. I investigated this way back and I recall, at least on mac, an issue with the "ctrl" key being registered as pressed when a lot of keys are pressed down at once, which causes notes to not register due to this line of code, and potentially also just keydown events not firing as expected.

I'll have to dig into it again. Any help on investigating this is welcome!

[kevinsqi]

I noticed this also happens when attempting to press down any 3 keys corresponding to sequential half steps (e.g. D, D#, E).

[kevinsqi]

This appears to not be specific to this component or to React - I created a codepen that demonstrates the issue for vanilla JS: https://codepen.io/kevinqi/pen/ZPxGoa

[kevinsqi]

ahh, it appears that this could be an issue with key rollover (a property of the keyboard), not anything JS related. See https://apple.stackexchange.com/a/70430/149027. If this is the issue, then it can't be fixed - it's an inherent limitation of the keyboard you use.

Both my macbook pro keyboard and mac magic keyboard, for example, are unable to register "s" + "e" + "d" when pressed down simultaneously. However, when I tested with a Das keyboard, it was able to register all 3 simultaneously.

@SeunghunSunmoonLee you mentioned that "I found other piano examples be able to do [6 keys at the same time]". Could you link me to an example piano where that works?

[kevinsqi]

Going to close this given that I think this is a hardware keyboard rollover issue and not related to the library, but if anyone can demonstrate otherwise, don't hesitate to reopen the issue.