Smooth scrolling on dynamically loaded textfield?

I’ve got a textfield with externally loaded text, that I’m scrolling using the usual scroll++ method, and invisible buttons… (

Is it possible to add a smooth friction effect to this, like on Claudio’s scroller at

I’m thinking it might not be possible, as this would require you to know the height of the text area, which is hard when using dynamically loaded text…

Is there a clever way to do this though???