Thanks to Karbiner for help in testing, I had a lot of things to fix. :)
I need at least one more person who wants to test the program, before I publish it.
For now program can generate object placement by 3 layers: Emergent layer; Edge of the forest layer; Undergrowth layer.
Emergent layer: base layer for forest, random placing object is selected color area except (default) 1m from color border.
Edge of the forest: random placing object on border of selected color area
Undergrowth layer: Places objects inside "Emergent layer", where is free space is min. 1m( by default 1m, can be changed in layer size value) between objects of "Emergent layer".
Emergent layer + Edge of the forest
Emergent layer + Edge of the forest + Undergrowth layer