How to grab screen coordinates of a PDF page file?

I need to dynamically obtain the screen coordinates of a PDF page. For example, if I select a particular region with a tool it will give me the coordinates of the selected region, furthermore, if i select a different region in the same page, I should get different coordinate points, x, y,z height etc.

Thus far, I have tried the Get Position activity but haven’t had any luck( returns the same coordinate points regardless where I select).