how to make Half Pedal action?

[It_Used]

Hello, I want to create a Half-Pedal action, but I don't know where to start, moreover, I don't even understand its essence, that's why I want to create it, I need a kick that will let me know where to start.
Thanks advance! ️

[d.healey]

@It_Used what do you want it to do, from the user's point of view?

[It_Used]

@d-healey I don’t know, I thought there were people here who understand the essence of how it works, and they would surely explain to me what functions it performs. Here’s what I found on the internet:

“Starting at a certain pedal position, the notes are slightly extended until they resonate completely when the pedal is fully depressed. Half-pedaling simulates the slow release of the dampers, with the dampers still resting lightly on the strings, limiting the string vibration. Accordingly, this only lightly extends the decay.

On some digital pianos, you can adjust the ‘half-pedal point’. This determines at what point in the pedal travel the half-pedal function begins to take effect.”

Is it really just a longer Release phase in AHDSR?
What makes it hard for me to grasp the essence is that the descriptions of this function are different everywhere :(

[HISEnberg]

@It_Used You will need to search academic journals to find the precise answer. The field you're looking for is Physical Modelling: IEEE and Julius Smith's work is always a good place to start: https://ccrma.stanford.edu/~jos/pasp/Literature_Piano_Acoustics_Synthesis.html#33543

I don't know much about acoustic modelling so I can't help you past saying that the the dampers in this context are usually coefficients within the string equation (not really an option with samplers). It get's complex with a lot of things to consider, but for a quicker and easy ansewr:

Option 1
The closest you could maybe get implies that high frequencies will fade faster than lows, i.e. a low pass filter whose cutoff is modulated by the pedal position.

Option 2
Map sustain-pedal positions to the release time of your AHDSR.
Midi 0 = pedal down, short release
127 = pedal up, long release

Option 3
Alternatively, a better method would be to load up a second sampler and crossfade between a regular and half pedal recording.

You can also mix some of these options together.

[It_Used]

@HISEnberg Thanks ️