Hi,
That's easily feasible by using the
Areas -
Falloff feature in a following way:
(1) Add the "trees" Forest object as excluding area inside of the "rocks" one
(2) Optionally, under Properties lower the
Scale (like in attached screen-shot to 10%)
(3) Enable the
Falloff -
Density and adjust the
Exclude amount as needed
(4) Mark the
Invert Curve check-box to apply it around this Exclude Area
Hope that helps. Feel free to check our on-line reference guide - how to "
To add scatter items around the perimeter of an exclude object" for more detailed info.
Best regards,