While trying to figure out this:
I discovered a problem in how the editor handles foliage painting.
As you paint, foliage instances are distributed throughout the radius of the brush, but as part of the brush moves over un-painted territory, the brush continues to paint throughout the full radius. This means that you are multiplying the max density anywhere the brush overlaps previously painted foliage.
Erase Density doesn’t solve this because it also erases at a fixed intensity rather than reducing instances to a fixed density.
I guess what we need is a “Flatten Density” brush.
