Drawing an hp / lp / cut filter curves with JS

Just Evan's icon

Need help creating a similar filter slider.

But I'm completely new to JS. Perhaps someone can help me?

TFL's icon

It's a M4L device. Open it and see how it's done there?

Just Evan's icon

I don't have this device, it looks like it's a concept, or the author's personal device. I also searched the entire Internet and didn't find anything similar.

Just Evan's icon

I also tried to do this using [function]