I loved this game! Gave you some feedback and ideas for fixing delay problems on the Ludum Dare site. I'll also copy it here just in case.
Amazing little gem of a game. I’m a drummer so I love rhythm games. I played the linux version.
I had a problem with delay, I tried mouse and keyboard separately, ended up using keyboard but the delay seemed to be the same. Trying very low latency on different platforms, using Unity, would have been impossible, so I don’t blame you, it’s a hard problem. In my case the clicks “hit” when I released the spacebar. By this I mean, the game registered the key down, but the delay made it feel like it was the key up that made the hit register.
Having played rhythm games before, and being a drummer, I adapted quickly to the delay, so after a couple of rounds of the same rhythm I just got the groove and could finish the rhythm without issues.
As a programmer, the way I’d solve it is by having some kind of calibration step beforehand. I just happen to have thought about this for a while because I was thinking of developing some software that would have these same issues with delay. My idea was to have like a “sync” step where a metronome is beating, and you’re supposed to hit the key at the same time as the metornome. You don’t get any audio feedback from your hits, but the game tells you that it’s registering them (so that you know that they’re not lost), with like a progress bar or something. But you don’t hear a sound when you hit, because that could throw you off. The first few beats are ignored (they probably aren’t very accurate), and then you save a list of the delays between each beat timestamp and when the user key events are registered. If everything goes well, and you average them out (also removing some outliers), that gives you the offset that you should apply to the game detection. If you repeat this process with different metronome BPMs, I think you’d get very reliable delay correction without the user having to input random numeric values via trial and error.
That’s what I always had in mind which could work while being pretty user friendly. With good user experience tweaks the calibration step could be a mix of tutorial and calibration, making it seamless for the user.
In any case, I loved the game, the way the music builds up as you nail the rhythm is very satisfying. I wish it was longer, but it’s a jam game!