The drop zones are defined by typing coordinates. As you type, the preview above is immediately updated, so you can position things by trial and improvement.

* Circle: centre_x, centre_y; radius<br>for example: <code>80, 100; 50</code>
* Polygon: x1, y1; x2, y2; ...; xn, yn<br>for example: <code>20, 60; 100, 60; 20, 100</code>
* Rectangle: top_left_x, top_left_y; width, height<br>for example: <code>20, 60; 80, 40</code>