scale node pivot point?

Hi everyone!

Is there any way of changing the scale node’s pivot point? I found that if I want to scale something in the compositor with the scale node, the center of the scaling will be the center of the whole image. That is not a problem if the object is in the dead center, but if it’s not, then it will move away if scaled.

I made a four corner pin tracking to change the screen of a tv with a plane with some other footage on it. The plane is hooked to empties, I can’t scale the plane, so I thought I should do it in the compositor. The problem is, the TV is not in the center, so it is being scaled around the image center, not the tv’s own center.

I thought maybe add a translate node and drivers to it, determine the slide of the pivot point, put it in a variable and feed it back to the drivers, pretty much compensating for the shift.
As for now I couldn’t figure out how to determine that difference.

Do you guys have any idea?
Thanks!

Good luck getting drivers to work in the compositor.

you mean they don’t work? at all?