Re: midi volume single note

[Gianmaria Lari]

On 14 November 2017 at 11:30, David Kastrup <address@hidden> wrote:

Gianmaria Lari <address@hidden> writes:

> On 13 November 2017 at 13:31, Caagr98 <address@hidden> wrote:
>
>> I was thinking of something like this:
>>
>> <<
>>   { c'1 }
>>   { s8 \set Voice.midiExpression=#0.5 s2.. Voice.midiExpression=#1 }
>> >> c'1
>>
>> That is, simultaneously: a) play a note, b) wait a short while, reduce
>> volume, wait until rest of the note is finished (2.. is 7/8 of a measure),
>> then reset to normal.
>>
>
> Thank you, perfect!!!!
>
> In case other people need it, here it is a complete example where c1 note
> is played reducing volume from maximum to minimum in step of 1/32.
>
> \version "2.19.80"
> right = \fixed c'' { c1 }
>
> dynamics = {
> s32 \set Voice.midiExpression=#1
> s32 \set Voice.midiExpression=#0.96774
> s32 \set Voice.midiExpression=#0.93548
> s32 \set Voice.midiExpression=#0.90323
[...]
> }
>
> \score {
>   \new Staff \with { midiInstrument = "accordion"}
>   \new Voice <<\right \dynamics>>
>   \midi {}
>   \layout {}
> }

Well, that calls for something programmatic I think.

Well, I was hoping that a nice guy pop up with your nice lily/scheme code:)  Thanks !!!

P.S.

I didn't wrote the long list of "s32 \set Voice.midiExpression=#xxxxx" by hand; I wrote some lines of code to generate them programmatically (much less practical then your code but better than write them by hand). Here it is the function I used:

        public string setVolume(float duration, int resolution, float volumeStart, float volumeEnd)

        {

            int steps = (int)((1 / duration) / (1 / (float)resolution));

            float val = (volumeStart - volumeEnd) / (steps - 1);

            string s = "";

            for (int i = 1; i <= steps; i++)

            {

                s += "s" + resolution.ToString()+ " " + "\\set Voice.midiExpression=#";

                s += Math.Round(volumeStart, 5).ToString() + "\n";

                volumeStart -= val;

            }

            return s;

        }