Spacing out regions (yet another one), need a little help

Getting Stuff Done Lua Scripting
#1

Hi there!

I recently encountered the problem that I needed to put space in between many regions. Like fanning them up in time. So I used a mean LLM, because I never had coded LUA before… (Back in the day I was a skilled Java programmer, long time ago, so I’m not a complete idiot, yet the LLM made a fool out of me eventually. It got only about 50% right and behaved like a mean person when being told so, so I spent a lot of time repairing broken generated code…)

So, this is what I came up with: ardour-lua-hacks/space-out-regions.lua at main · DrNI/ardour-lua-hacks · GitHub

It does work quite well, I think. The undo/redo also does work.

However, what doesn’t work is that it operates on regions on multiple tracks successfully. It has this current_shift variable, and this actually should depend on the track the region lives in, then it would be fine.

So, I would want something like this (not on GitHub, since it doesn’t work):

    -- iterate over selected regions
    for i, r in ipairs(region_table) do

        local pos = r:position()
        local track = r:track()

        -- seeing this region on this track first time, so shift is initialized to 0
        if trackShiftMap[track] == nil then
            trackShiftMap[track] = 0
        end

        -- Undo system needs this
        r:to_stateful():clear_changes()

        -- Do the thing! Move the region!
        r:set_position(pos + Temporal.timecnt_t(trackShiftMap[track]))

        -- Feed undo system with this change
        Session:add_stateful_diff_command(r:to_statefuldestructible ())

        -- Re-compute shift for next region
        trackShiftMap[track] = trackShiftMap[track] + base_shift
    end

However, Region:track() does not exist, it’s a mere fantasy of AI.

So, how could I find the track a region belongs to?

Having reached that point I found that there is another script already doing this, yet it’s undo/redo apparently seems broken and it also is for single tracks only: ardour-scripts/A7/space regions single track.lua at master · davidhealey/ardour-scripts · GitHub

Use cases for this include beats that do not live on a grid, and that you separated into regions using the Rhythm Ferret… and then you want these slower or faster.

Any hints are appreciated.

Best
Niels

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#2

tl;dr: look at some example-code find_track_for_region.

In Ardour every Track has-a Playlist, and the Playlist contains Regions.

But since playlists can be shared on many tracks, and playlists can be nested, there may not be a unique answer on which track(s) a given region is played.

So the only way to find out on which track(s) a given region is used, is to iterate over all tracks, all the track’s playlists. For a large session, your script could do this first and cache the result.

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