Opensource motto is: not reinvent the wheel.

We suggest to use qtpfsgui for tonemapping as it is opensource project doing it very good.

By the way feature request should be more detailed to help developers solving your issues.

e.g. you cannot ask Ferrari: make a good looking car! It's pretty obvious. You cannot ask neither: make a car looking as Lamborgini! This is pretty useless because it will not be taken into consideration.

I close this request due to non sense hoping for better focused requests.