Hi there,
I was just thinking: Would a groove tool, like the one for Reaper be possible in Renoise? I am not sure if the API will fully allow for this.
What do you think?
Have you seen?
I think finding out should be your new Lua coding project Fladd 
, the Reaper thing looks interesting!
Yes, I know those tools, but what I had in mind is something entirely different. The idea is to extract the groove out of other beats (audio, midi) and apply this groove to a track in Renoise.
In Reaper such tool exists, and it comes with a long list of groove files that, for instance, are recorded from an MPC.
Maybe Renoises slicer functionality could be used for this? Analyze and extract ‘groove templates’ (= slice marker positions) from beats and apply these on pattern content by inserting values in the delay column.
Yes, I also had something like this in mind. Actually the idea came to me when looking at the slices-to-pattern tool, because I thought this is already half the work 
The question is how to apply these to already filled patterns then…
Globally (rather than per track) by using BPM changes. Something I have suggested in the past but think the calculations might be more than just a little bit harder than delay column!
the amount of ‘beats’ in the extracted groove template from a sample should correspond to the amount of ‘beats’ in the pattern and be repeated if necessary.
So if you’re analyzing/slicing a 1 bar drum loop fitting in 16 lines at a lbp of 4, the groove gets repeated 4 times in a pattern of 64, or something? 
lol ableton live feature. 
The groove should certainly be applied to specific individual track, and not globally…