@aaronventure
But to gather all tempo changes one will have to play once through whole track/project, store changes and than eventualy construct tempo map. One that is allready created by host (or, reather Melodyne) if you just drag audio to timeline (at least, this is how it works in Studio one and Sonar, probbably Pro Tools and some others). And since the tempo map already exists, I was hoping to be able to pull it in at the plugin initialization and use the data to plot the bars inside the piano roll. If the tempo map is not created at the time of plugin initialization, the BPM is sufficient, obviously. But at some point, the tempo map will be created and then the plugin would have to update the entire grid. And move all notes along with it. So, it cannot be achieved through a stream/realtime mechanics you are suggesting.

@d-healey
Yes, but in order to draw grid of piano roll that will reflect all tempo fluctuations throughout project/track I will need tempo map. I guess this is what Im asking actualy, is it possible to get tempo map of a project, not just average BPM?

Allright, hopefully last question. Engine.getHostBpm() will return global project tempo. But what about variable tempo extracted from live recordings and imposed on host timeline as tempo map?

@d-healey
Thanks again. Is there an official channel for feature requests?

Eh, sorry for the bother, some additional questions pop up by themselves... is it possible to at least get a tempo map from the host? How else can I sync my piano roll with the host? After a day of research, it seems trivial to achieve this with ARA, but almost impossible with vanilla VST? HISE + ARA? Possible? In the future?

@karlito31
Thank you.

@karlito31
Actually, if it can't be done like that, would it be possible to implement whole piano roll in plugin and sand midi messages created in it to host (or other VST Instruments)?

@d-healey
I sure will, thanks.

@d-healey
That's exactly what I'm trying to avoid. :)

are there any callbacks on note duration, position or velocity changes from host that plugin can react to?