Dragging/dropping elements onto designated area then outputting coordinates

Dragging/dropping elements onto designated area then outputting coordinates

I'm working on an AngularJS app which will allow a user to drag HTML
elements onto a designated area. I then need to be able to output the
coordinates of the elements dropped onto the designated area.
The UI will look something like this:

So the user drags objects from the panel on the left onto the designated
area on the right. They will then be able to set a number of properties
for that element as shown in the bottom panel (however this is something
I'm confident in doing). What I'm unsure about is how I can create the
functionality to allow objects to be dropped at a certain position on the
designated area, then have the web app output the coordinates of all the
objects.
Any ideas on how to accomplish this functionality?