Originally Posted by Jim Fogle
Musocity, the above is one of the best tip descriptions you have made. Great visual step-by-step instructions.
That's from another post but I will try and do a simplified easy to understand version here.

When you choose a Style in Biab and generate it will read all the XT2 ST2 files for the RTs in that Style from the Soloists folder.
These contain all the solo and chord data for the RC, SMT & RT source files in the RealTracks folder.

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The Live Arranger will work the same way, you set the Style, tempo and Key, you can also change these during the performance with keyswitches from the presets (Style Key Tempo),
when the user inputs a C chord and is in the Play Mode it will scan the data for a C chord section in the source files and start playing the file from the position "value" of the C chord in the source file, when the bars of that chord have played out it will have another from another section of the files lined up to play.
reaper.CF_Preview_SetValue(track1, "D_POSITION", 4)

If the source file is transposed 2 semitones
reaper.CF_Preview_SetValue(track1, "D_PITCH", 2)

If the source file bpm is 110 and it needs to playback @ 120 then the playrate is changed
reaper.CF_Preview_SetValue(track1, "D_PLAYRATE", 1.090909)

Once the values are set that file section is played
reaper.CF_Preview_Play(track1)

It's doing this at the same time for each track in the Style as I showed in the video above playing different sections with the Bass and Drums.

So as the user changes a chord it will instantly play all tracks from their required section from within the RT source files.
The Drums will follow the part A or B inputted by the user, this will say whether to play an A or B or A ending or B ending section of a RT.

I could make this all up myself to use Biab RTs RDs with Reaper but I would have to map out all the RTs to chord data file.
I would rather see PG do this as they already have all this data mapped out in the XT2 ST2.
Reaper will playback the Win Mac compressed formats wma & m4a the same with the BBPlugin now works in Reaper playing the source files direct.

Please post any feedback how you think it should work and any keyswitches you think it would need to perform Live.
I don't play keyboard, I'm not a musician so I'm at a lost to know exactly what you would need ?

This is an old one I made for Reaper that used the existing track regions to access different chord sections :
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