I have a grid on which boxes can be placed like in the image below.
The main constraint is that two boxes **must not overlap**. Box X is not allowed to be on top of box E.

![elements on a 2d grid][2]

Now given each box should be allowed to be copied and pasted, what would be a good way to determine the target position for the pasted box?

In other 2D applications like Photoshop pasted elements overlap the original element or just are placed in the center of the screen. ([As already discussed over there][1])

But if there is no space for the element to fit in the center of the screen, what would a user expect where the element appears? 

Are there any applications which have already solved this? 

Would it be a good idea to expand the paste operation by one step, allowing the user to select a suitable position by them self? 

 - pressing ctrl+v to enter pasting mode
 - demand clicking on a point giving feedback if the position is allowed
 - if yes then inserting the element

I think this could be to complicated compared to copy/paste in other applications.

  [1]: http://ux.stackexchange.com/questions/41298/where-should-pasted-objects-in-a-drawing-application-be-placed
  [2]: https://i.sstatic.net/4sWHL.png