I’d been seeing two-dimensional tonality grids for years; it occurred to me that I could add the idea of having tonal motion cause visual motion to that kind of representation. In V19, the pitch names light up when a note is sounding, and all the triadic connections between sounding pitches appear.

One thing I liked about this display was that it showed how some chord progressions “came back the same way they left” (meaning that they returned to the same point they started) and some “went into another universe” (for example, started in C and ended in D-double-flat — the same note on the piano, but a different note conceptually).