ADSR envelope generator

[codeninja-ru]

I've read the documentation, but I'm still struggling to figure out the best way to implement an ADSR envelope generator. 🤔
I came across the concept of an ADSR envelope while researching music envelopes on Wikipedia (https://en.wikipedia.org/wiki/Envelope_(music)). It seems like using an ADSR envelope would be ideal for what I want to achieve.

To give you some context, my goal is to divide a sine wave into multiple shorter sounds, each with its own frequency. I would like these sounds to have distinctive attack, decay, sustain, and release characteristics. However, I'm not sure how to go about implementing this.

I would greatly appreciate any guidance or examples on how to create an ADSR envelope generator in my implementation.

Thank you in advance!