How to stop overlapping?

[fishrod]

How can you stop the overlapping of objects?
When I hold my mouse button it creates grass tiles works fine.
But the event keeps placing tiles even when there is already one placed.
How I can I fix this?

Example mfa (Look in the debug bar to see how many objects are placed):
http://download948.mediafire.com/y7r...mc/Example.mfa

I hope you can help me with this.
Thanks!

[King_Cool]

In short, create an invisible Detection Object which allways positions to the Mouse Cursor coordinates.
Then only create Tiles when the Detection Object is NOT overlapping other Tiles.

[fishrod]

Thanks got it working.