Pan / zoom fix

Little sample of what I’m needing to do - I have a bitmap as a child that is masked. User can zoom into, and then pan the image as shown in the lower sample. I ned the image to zoom always from the mask center, or possibly any point. So when the user zooms in, pans over, and then zooms out, the image zooms from where they’re at, not top left…

I am close to getting this working - trying with a matrix - but not there and am hoping someone has a bit of code handy.