Re: MIDI rendition of things like rall./acc./rit./fermata

[Dan Eble]

On Jun 12, 2021, at 18:48, David Kastrup <dak@gnu.org> wrote:
> 
> So how robust (or not) would be the following approach?  Make it
> possible to write in the timing track something like
> 
> \rit 2/3 { \skip 1*2 }
> 
> with the effect that some run-always translator keeps adjusting
> tempoWholesPerMinute during the \skip (in proportion to where the time
> is) until it is at 2/3 the speed at the end when it gets reset.

As a user, I think I would rather specify the tempo at the endpoint.  Is there 
any hope of handling tempo adjustments like dynamic adjustments?

    \mf … \< … \f

    \tempo 4 = 90 … \startLinearTempoChange … \tempo 4 = 60

I don't remember very clearly how the dynamic performance looks ahead to manage 
as it does, but I think it might be that the MIDI generation occurs in a second 
pass, and a velocity value isn't actually needed until then.  It might be 
possible to record a piecewise function for the tempo during normal iteration, 
and then use that to stretch or compress MIDI time as the raw MIDI events are 
being generated.

I would love to have this feature.  I'm glad you're considering it.
— 
Dan