Playtime: Interactive auto-accompaniment mode (aka Style player)

[askoriy]

I would like to have an interactive auto-accompaniment feature, similar to those in Yamaha PSR, One Man Band, vArranger, Giglad, etc.

One of the problems with cell-based playsets is the need to record separate cells for different chord progressions and manage them individually. Launching a cell with a non-complementary chord progression can suddenly ruin the entire groove. This feature would significantly improve productivity during live performances as well as during the early stages of song design.

In my opinion, two additional features for cells are needed:

• Auto-transpose Mode: If enabled, the MIDI notes in the cell would be transposed on the fly based on the chord being played on the MIDI keyboard.
• Fill-In Mode: Instead of starting the cell from the beginning at the next measure, it would play immediately but from the time remaining until the end of the current measure (or possibly until the current cell finishes - needs further consideration). In result the Fill-in cell would synchronize with other cells. By default Fill-in cells should play only once and switch to the next (non Fill-In) or current cell after finish.

For Auto-transpose Mode, additional parameters are needed: the original chord recorded in the cell, the range of the lowest and highest notes to transpose, and retrigger behaviour on chord change .

Of course, there are many technical questions to discuss, such as chord recognition, quantization, how to handle late chord changes, etc., but even a limited version of this feature in Playtime would be amazing.