Widget to edit envelope profile

[mastupristi]

Hi

I need a Widget similar to this:
widget-example.png

You can find it in audacity, Equalizer dialog.

There is something similar online? Or I have to write it from scratch? In this case what is the starting point?

best regards
Max

[ChrisW67]

You may be able to build something like this on top of a Qwt graph widget.