overlay sample

{
    "type": "region_overlay",
    "id": "field_contents",
    "regions": [ "all" ],
    "field_coverage": {
      "percent_coverage": 20,
      "default_ter": "t_shrub",
      "other": {
        "t_tree_young": 0.2,
        "t_tree": 0.1,
        "t_tree_birch": 0.05,
        "t_tree_elm": 0.05,
        "t_tree_cottonwood": 0.05,
        "t_tree_pine": 0.1,
        "t_tree_maple": 0.1,
        "t_tree_willow": 0.1,
        "t_tree_hickory": 0.1,
        "t_tree_walnut": 0.05,
        "t_tree_chestnut": 0.05,
        "t_tree_hazelnut": 0.02,
        "t_tree_beech": 0.02,
        "t_tree_blackjack": 0.05,
        "t_tree_coffee": 0.02,
        "t_tree_apple": 0.02,
        "t_tree_apricot": 0.02,
        "t_tree_cherry": 0.02,
        "t_tree_peach": 0.02,
        "t_tree_pear": 0.02,
        "t_tree_plum": 0.02,
        "t_tree_elderberry": 0.02,
        "t_tree_mulberry": 0.02,
        "t_tree_deadpine": 0.05,
        "t_tree_hickory_dead": 0.05,
        "t_tree_dead": 0.05,
        "t_shrub_blueberry": 0.4166,
        "t_shrub_strawberry": 0.4166,
        "t_shrub_blackberry": 0.4166,
        "t_shrub_raspberry": 0.4166,
        "t_shrub_huckleberry": 0.4166,
        "t_shrub_grape": 0.2066,
        "t_shrub_rose": 4.3333,
        "t_shrub_hydrangea": 4.3333,
        "t_shrub_lilac": 4.3333,
        "f_black_eyed_susan": 4.3333,
        "f_lily": 4.3333,
        "f_flower_tulip": 8.3333,
        "f_flower_spurge": 8.3333,
        "f_chamomile": 8.3333,
        "f_mutpoppy": 8.3333,
        "f_bluebell": 8.3333,
        "f_dahlia": 8.3333,
        "f_datura": 4.3333,
        "f_dandelion": 8.3333,
        "f_boulder_small": 1,
        "f_boulder_medium": 0.6666,
        "f_boulder_large": 0.3333
      },
      "boost_chance": 0.833,
      "boosted_percent_coverage": 2.5,
      "boosted_other": {
        "t_tree_young": 0.2,
        "t_tree": 0.1,
        "t_tree_birch": 0.05,
        "t_tree_elm": 0.05,
        "t_tree_cottonwood": 0.05,
        "t_tree_pine": 0.1,
        "t_tree_maple": 0.1,
        "t_tree_willow": 0.1,
        "t_tree_hickory": 0.1,
        "t_tree_walnut": 0.05,
        "t_tree_chestnut": 0.05,
        "t_tree_hazelnut": 0.02,
        "t_tree_beech": 0.02,
        "t_tree_blackjack": 0.05,
        "t_tree_coffee": 0.02,
        "t_tree_apple": 0.02,
        "t_tree_apricot": 0.02,
        "t_tree_cherry": 0.02,
        "t_tree_peach": 0.02,
        "t_tree_pear": 0.02,
        "t_tree_plum": 0.02,
        "t_tree_elderberry": 0.02,
        "t_tree_mulberry": 0.02,
        "t_tree_deadpine": 0.05,
        "t_tree_hickory_dead": 0.05,
        "t_tree_dead": 0.05,
        "t_shrub_blueberry": 8.0,
        "t_shrub_strawberry": 5.0,
        "t_shrub_blackberry": 5.0,
        "t_shrub_raspberry": 8.0,
        "t_shrub_huckleberry": 5.0,
        "t_shrub_grape": 5.0,
        "t_shrub_rose": 3.5,
        "t_shrub_hydrangea": 3.5,
        "t_shrub_lilac": 3.5,
        "f_black_eyed_susan": 3.5,
        "f_lily": 3.5,
        "f_flower_tulip": 3.5,
        "f_flower_spurge": 3.5,
        "f_mutpoppy": 3.5,
        "f_bluebell": 3.5,
        "f_dahlia": 3.5,
        "f_datura": 0.2,
        "f_dandelion": 5.0
      },
      "boosted_other_percent": 50.0
    }
  },