So i have task to create automatic lakes in area covered by mask and it not impact the lakes spawn area, only rivers (if they will be turned on)
this thing is important, because i want to receive proper mask of all lakes inside - if i will apply mask after lakes already summoned on all map - i have risk to cut some of them and have water walls in-game 
cutted lakes mask on third output is those future water-walls:
non-automatic hand-placing is only available option as i understand
