copy all standard Dreambuilder mods in from the old subgame

(exactly as last supplied there, updates to these mods will follow later)

1 files changed, 737 insertions, 0 deletions

diff --git a/biome_lib/init.lua b/biome_lib/init.lua
new file mode 100644
index 0000000..01a17d2
--- /dev/null
+++ b/biome_lib/init.lua
@@ -0,0 +1,737 @@
+-- Plantlife library mod by Vanessa Ezekowitz
+--
+-- License:  WTFPL
+--
+-- I got the temperature map idea from "hmmmm", values used for it came from
+-- Splizard's snow mod.
+--
+
+-- Various settings - most of these probably won't need to be changed
+
+biome_lib = {}
+
+plantslib = setmetatable({}, { __index=function(t,k) print("Use of deprecated function:", k) return biome_lib[k] end })
+
+biome_lib.blocklist_aircheck = {}
+biome_lib.blocklist_no_aircheck = {}
+
+biome_lib.surface_nodes_aircheck = {}
+biome_lib.surface_nodes_no_aircheck = {}
+
+biome_lib.surfaceslist_aircheck = {}
+biome_lib.surfaceslist_no_aircheck = {}
+
+biome_lib.actioncount_aircheck = {}
+biome_lib.actioncount_no_aircheck = {}
+
+biome_lib.actionslist_aircheck = {}
+biome_lib.actionslist_no_aircheck = {}
+
+biome_lib.modpath = minetest.get_modpath("biome_lib")
+
+biome_lib.total_no_aircheck_calls = 0
+
+-- Boilerplate to support localized strings if intllib mod is installed.
+local S
+if minetest.get_modpath("intllib") then
+	S = intllib.Getter()
+else
+	S = function(s) return s end
+end
+biome_lib.intllib = S
+
+local DEBUG = false --... except if you want to spam the console with debugging info :-)
+
+function biome_lib:dbg(msg)
+	if DEBUG then
+		print("[Plantlife] "..msg)
+		minetest.log("verbose", "[Plantlife] "..msg)
+	end
+end
+
+biome_lib.plantlife_seed_diff = 329	-- needs to be global so other mods can see it
+
+local perlin_octaves = 3
+local perlin_persistence = 0.6
+local perlin_scale = 100
+
+local temperature_seeddiff = 112
+local temperature_octaves = 3
+local temperature_persistence = 0.5
+local temperature_scale = 150
+
+local humidity_seeddiff = 9130
+local humidity_octaves = 3
+local humidity_persistence = 0.5
+local humidity_scale = 250
+
+local time_scale = 1
+local time_speed = tonumber(minetest.setting_get("time_speed"))
+
+if time_speed and time_speed > 0 then
+	time_scale = 72 / time_speed
+end
+
+--PerlinNoise(seed, octaves, persistence, scale)
+
+biome_lib.perlin_temperature = PerlinNoise(temperature_seeddiff, temperature_octaves, temperature_persistence, temperature_scale)
+biome_lib.perlin_humidity = PerlinNoise(humidity_seeddiff, humidity_octaves, humidity_persistence, humidity_scale)
+
+-- Local functions
+
+function biome_lib:is_node_loaded(node_pos)
+	local n = minetest.get_node_or_nil(node_pos)
+	if (not n) or (n.name == "ignore") then
+		return false
+	end
+	return true
+end
+
+function biome_lib:set_defaults(biome)
+	biome.seed_diff = biome.seed_diff or 0
+	biome.min_elevation = biome.min_elevation or -31000
+	biome.max_elevation = biome.max_elevation or 31000
+	biome.temp_min = biome.temp_min or 1
+	biome.temp_max = biome.temp_max or -1
+	biome.humidity_min = biome.humidity_min or 1
+	biome.humidity_max = biome.humidity_max or -1
+	biome.plantlife_limit = biome.plantlife_limit or 0.1
+	biome.near_nodes_vertical = biome.near_nodes_vertical or 1
+
+-- specific to on-generate
+
+	biome.neighbors = biome.neighbors or biome.surface
+	biome.near_nodes_size = biome.near_nodes_size or 0
+	biome.near_nodes_count = biome.near_nodes_count or 1
+	biome.rarity = biome.rarity or 50
+	biome.max_count = biome.max_count or 5
+	if biome.check_air ~= false then biome.check_air = true end
+
+-- specific to abm spawner
+	biome.seed_diff = biome.seed_diff or 0
+	biome.light_min = biome.light_min or 0
+	biome.light_max = biome.light_max or 15
+	biome.depth_max = biome.depth_max or 1
+	biome.facedir = biome.facedir or 0
+end
+
+local function search_table(t, s)
+	for i = 1, #t do
+		if t[i] == s then return true end
+	end
+	return false
+end
+
+-- register the list of surfaces to spawn stuff on, filtering out all duplicates.
+-- separate the items by air-checking or non-air-checking map eval methods
+
+function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
+
+	-- if calling code passes an undefined node for a surface or 
+	-- as a node to be spawned, don't register an action for it.
+
+	if type(nodes_or_function_or_model) == "string"
+	  and string.find(nodes_or_function_or_model, ":")
+	  and not minetest.registered_nodes[nodes_or_function_or_model] then
+		biome_lib:dbg("Warning: Ignored registration for undefined spawn node: "..dump(nodes_or_function_or_model))
+		return
+	end
+
+	if type(nodes_or_function_or_model) == "string"
+	  and not string.find(nodes_or_function_or_model, ":") then
+		biome_lib:dbg("Warning: Registered function call using deprecated string method: "..dump(nodes_or_function_or_model))
+	end
+
+	if biomedef.check_air == false then 
+		biome_lib:dbg("Register no-air-check mapgen hook: "..dump(nodes_or_function_or_model))
+		biome_lib.actionslist_no_aircheck[#biome_lib.actionslist_no_aircheck + 1] = { biomedef, nodes_or_function_or_model }
+		local s = biomedef.surface
+		if type(s) == "string" then
+			if s and (string.find(s, "^group:") or minetest.registered_nodes[s]) then
+				if not search_table(biome_lib.surfaceslist_no_aircheck, s) then
+					biome_lib.surfaceslist_no_aircheck[#biome_lib.surfaceslist_no_aircheck + 1] = s
+				end
+			else
+				biome_lib:dbg("Warning: Ignored no-air-check registration for undefined surface node: "..dump(s))
+			end
+		else
+			for i = 1, #biomedef.surface do
+				local s = biomedef.surface[i]
+				if s and (string.find(s, "^group:") or minetest.registered_nodes[s]) then
+					if not search_table(biome_lib.surfaceslist_no_aircheck, s) then
+						biome_lib.surfaceslist_no_aircheck[#biome_lib.surfaceslist_no_aircheck + 1] = s
+					end
+				else
+					biome_lib:dbg("Warning: Ignored no-air-check registration for undefined surface node: "..dump(s))
+				end
+			end
+		end
+	else
+		biome_lib:dbg("Register with-air-checking mapgen hook: "..dump(nodes_or_function_or_model))
+		biome_lib.actionslist_aircheck[#biome_lib.actionslist_aircheck + 1] = { biomedef, nodes_or_function_or_model }
+		local s = biomedef.surface
+		if type(s) == "string" then
+			if s and (string.find(s, "^group:") or minetest.registered_nodes[s]) then
+				if not search_table(biome_lib.surfaceslist_aircheck, s) then
+					biome_lib.surfaceslist_aircheck[#biome_lib.surfaceslist_aircheck + 1] = s
+				end
+			else
+				biome_lib:dbg("Warning: Ignored with-air-checking registration for undefined surface node: "..dump(s))
+			end
+		else
+			for i = 1, #biomedef.surface do
+				local s = biomedef.surface[i]
+				if s and (string.find(s, "^group:") or minetest.registered_nodes[s]) then
+					if not search_table(biome_lib.surfaceslist_aircheck, s) then
+						biome_lib.surfaceslist_aircheck[#biome_lib.surfaceslist_aircheck + 1] = s
+					end
+				else
+					biome_lib:dbg("Warning: Ignored with-air-checking registration for undefined surface node: "..dump(s))
+				end
+			end
+		end
+	end
+end
+
+function biome_lib:populate_surfaces(biome, nodes_or_function_or_model, snodes, checkair)
+
+	biome_lib:set_defaults(biome)
+
+	-- filter stage 1 - find nodes from the supplied surfaces that are within the current biome.
+
+	local in_biome_nodes = {}
+	local perlin_fertile_area = minetest.get_perlin(biome.seed_diff, perlin_octaves, perlin_persistence, perlin_scale)
+
+	for i = 1, #snodes do
+		local pos = snodes[i]
+		local p_top = { x = pos.x, y = pos.y + 1, z = pos.z }
+		local noise1 = perlin_fertile_area:get2d({x=pos.x, y=pos.z})
+		local noise2 = biome_lib.perlin_temperature:get2d({x=pos.x, y=pos.z})
+		local noise3 = biome_lib.perlin_humidity:get2d({x=pos.x+150, y=pos.z+50})
+		local biome_surfaces_string = dump(biome.surface)
+		local surface_ok = false
+
+		if not biome.depth then
+			local dest_node = minetest.get_node(pos)
+			if string.find(biome_surfaces_string, dest_node.name) then
+				surface_ok = true
+			else
+				if string.find(biome_surfaces_string, "group:") then
+					for j = 1, #biome.surface do
+						if string.find(biome.surface[j], "^group:") 
+						  and minetest.get_item_group(dest_node.name, biome.surface[j]) then
+							surface_ok = true
+							break
+						end
+					end
+				end
+			end
+		elseif not string.find(biome_surfaces_string, minetest.get_node({ x = pos.x, y = pos.y-biome.depth-1, z = pos.z }).name) then
+			surface_ok = true
+		end
+
+		if surface_ok
+		  and (not checkair or minetest.get_node(p_top).name == "air")
+		  and pos.y >= biome.min_elevation
+		  and pos.y <= biome.max_elevation
+		  and noise1 > biome.plantlife_limit
+		  and noise2 <= biome.temp_min
+		  and noise2 >= biome.temp_max
+		  and noise3 <= biome.humidity_min
+		  and noise3 >= biome.humidity_max
+		  and (not biome.ncount or #(minetest.find_nodes_in_area({x=pos.x-1, y=pos.y, z=pos.z-1}, {x=pos.x+1, y=pos.y, z=pos.z+1}, biome.neighbors)) > biome.ncount)
+		  and (not biome.near_nodes or #(minetest.find_nodes_in_area({x=pos.x-biome.near_nodes_size, y=pos.y-biome.near_nodes_vertical, z=pos.z-biome.near_nodes_size}, {x=pos.x+biome.near_nodes_size, y=pos.y+biome.near_nodes_vertical, z=pos.z+biome.near_nodes_size}, biome.near_nodes)) >= biome.near_nodes_count)
+		  and math.random(1,100) > biome.rarity
+		  and (not biome.below_nodes or string.find(dump(biome.below_nodes), minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z}).name) )
+		  then
+			in_biome_nodes[#in_biome_nodes + 1] = pos
+		end
+	end
+
+	-- filter stage 2 - find places within that biome area to place the plants.
+
+	local num_in_biome_nodes = #in_biome_nodes
+
+	if num_in_biome_nodes > 0 then
+		for i = 1, math.min(biome.max_count, num_in_biome_nodes) do
+			local tries = 0
+			local spawned = false
+			while tries < 2 and not spawned do
+				local pos = in_biome_nodes[math.random(1, num_in_biome_nodes)]
+				if biome.spawn_replace_node then
+					pos.y = pos.y-1
+				end
+				local p_top = { x = pos.x, y = pos.y + 1, z = pos.z }
+
+				if not (biome.avoid_nodes and biome.avoid_radius and minetest.find_node_near(p_top, biome.avoid_radius + math.random(-1.5,2), biome.avoid_nodes)) then
+					if biome.delete_above then
+						minetest.remove_node(p_top)
+						minetest.remove_node({x=p_top.x, y=p_top.y+1, z=p_top.z})
+					end
+
+					if biome.delete_above_surround then
+						minetest.remove_node({x=p_top.x-1, y=p_top.y, z=p_top.z})
+						minetest.remove_node({x=p_top.x+1, y=p_top.y, z=p_top.z})
+						minetest.remove_node({x=p_top.x,   y=p_top.y, z=p_top.z-1})
+						minetest.remove_node({x=p_top.x,   y=p_top.y, z=p_top.z+1})
+
+						minetest.remove_node({x=p_top.x-1, y=p_top.y+1, z=p_top.z})
+						minetest.remove_node({x=p_top.x+1, y=p_top.y+1, z=p_top.z})
+						minetest.remove_node({x=p_top.x,   y=p_top.y+1, z=p_top.z-1})
+						minetest.remove_node({x=p_top.x,   y=p_top.y+1, z=p_top.z+1})
+					end
+
+					if biome.spawn_replace_node then
+						minetest.remove_node(pos)
+					end
+
+					local objtype = type(nodes_or_function_or_model)
+
+					if objtype == "table" then
+						if nodes_or_function_or_model.axiom then
+							biome_lib:generate_tree(pos, nodes_or_function_or_model)
+							spawned = true
+						else
+							local fdir = nil
+							if biome.random_facedir then
+								fdir = math.random(biome.random_facedir[1], biome.random_facedir[2])
+							end
+							minetest.set_node(p_top, { name = nodes_or_function_or_model[math.random(#nodes_or_function_or_model)], param2 = fdir })
+							spawned = true
+						end
+					elseif objtype == "string" and
+					  minetest.registered_nodes[nodes_or_function_or_model] then
+						local fdir = nil
+						if biome.random_facedir then
+							fdir = math.random(biome.random_facedir[1], biome.random_facedir[2])
+						end
+						minetest.set_node(p_top, { name = nodes_or_function_or_model, param2 = fdir })
+						spawned = true
+					elseif objtype == "function" then
+						nodes_or_function_or_model(pos)
+						spawned = true
+					elseif objtype == "string" and pcall(loadstring(("return %s(...)"):
+						format(nodes_or_function_or_model)),pos) then
+						spawned = true
+					else
+						biome_lib:dbg("Warning: Ignored invalid definition for object "..dump(nodes_or_function_or_model).." that was pointed at {"..dump(pos).."}")
+					end
+				else
+					tries = tries + 1
+				end
+			end
+		end
+	end
+end
+
+-- Primary mapgen spawner, for mods that can work with air checking enabled on
+-- a surface during the initial map read stage.
+
+function biome_lib:generate_block_with_air_checking()
+	if #biome_lib.blocklist_aircheck > 0 then
+
+		local minp =		biome_lib.blocklist_aircheck[1][1]
+		local maxp =		biome_lib.blocklist_aircheck[1][2]
+
+		-- use the block hash as a unique key into the surface nodes
+		-- tables, so that we can write the tables thread-safely.
+
+		local blockhash =	minetest.hash_node_position(minp)
+
+		if not biome_lib.surface_nodes_aircheck.blockhash then
+
+			if type(minetest.find_nodes_in_area_under_air) == "function" then -- use newer API call
+				biome_lib.surface_nodes_aircheck.blockhash =
+					minetest.find_nodes_in_area_under_air(minp, maxp, biome_lib.surfaceslist_aircheck)
+			else
+				local search_area = minetest.find_nodes_in_area(minp, maxp, biome_lib.surfaceslist_aircheck)
+
+				-- search the generated block for air-bounded surfaces the slow way.
+
+				biome_lib.surface_nodes_aircheck.blockhash = {}
+
+				for i = 1, #search_area do
+				local pos = search_area[i]
+					local p_top = { x=pos.x, y=pos.y+1, z=pos.z }
+					if minetest.get_node(p_top).name == "air" then
+						biome_lib.surface_nodes_aircheck.blockhash[#biome_lib.surface_nodes_aircheck.blockhash + 1] = pos
+					end
+				end
+			end
+			biome_lib.actioncount_aircheck.blockhash = 1
+
+		else
+			if biome_lib.actioncount_aircheck.blockhash <= #biome_lib.actionslist_aircheck then
+				-- [1] is biome, [2] is node/function/model
+				biome_lib:populate_surfaces(
+					biome_lib.actionslist_aircheck[biome_lib.actioncount_aircheck.blockhash][1],
+					biome_lib.actionslist_aircheck[biome_lib.actioncount_aircheck.blockhash][2],
+					biome_lib.surface_nodes_aircheck.blockhash, true)
+				biome_lib.actioncount_aircheck.blockhash = biome_lib.actioncount_aircheck.blockhash + 1
+			else
+				if biome_lib.surface_nodes_aircheck.blockhash then
+					table.remove(biome_lib.blocklist_aircheck, 1)
+					biome_lib.surface_nodes_aircheck.blockhash = nil
+				end
+			end
+		end
+	end
+end
+
+-- Secondary mapgen spawner, for mods that require disabling of
+-- checking for air during the initial map read stage.
+
+function biome_lib:generate_block_no_aircheck()
+	if #biome_lib.blocklist_no_aircheck > 0 then
+
+		local minp =		biome_lib.blocklist_no_aircheck[1][1]
+		local maxp =		biome_lib.blocklist_no_aircheck[1][2]
+
+		local blockhash =	minetest.hash_node_position(minp)
+
+		if not biome_lib.surface_nodes_no_aircheck.blockhash then
+
+			-- directly read the block to be searched into the chunk cache
+
+			biome_lib.surface_nodes_no_aircheck.blockhash =
+				minetest.find_nodes_in_area(minp, maxp, biome_lib.surfaceslist_no_aircheck)
+			biome_lib.actioncount_no_aircheck.blockhash = 1
+
+		else
+			if biome_lib.actioncount_no_aircheck.blockhash <= #biome_lib.actionslist_no_aircheck then
+				biome_lib:populate_surfaces(
+					biome_lib.actionslist_no_aircheck[biome_lib.actioncount_no_aircheck.blockhash][1],
+					biome_lib.actionslist_no_aircheck[biome_lib.actioncount_no_aircheck.blockhash][2],
+					biome_lib.surface_nodes_no_aircheck.blockhash, false)
+				biome_lib.actioncount_no_aircheck.blockhash = biome_lib.actioncount_no_aircheck.blockhash + 1
+			else
+				if biome_lib.surface_nodes_no_aircheck.blockhash then
+					table.remove(biome_lib.blocklist_no_aircheck, 1)
+					biome_lib.surface_nodes_no_aircheck.blockhash = nil
+				end
+			end
+		end
+	end
+end
+
+-- "Record" the chunks being generated by the core mapgen
+
+minetest.register_on_generated(function(minp, maxp, blockseed)
+	biome_lib.blocklist_aircheck[#biome_lib.blocklist_aircheck + 1] = { minp, maxp }
+end)
+
+minetest.register_on_generated(function(minp, maxp, blockseed)
+	biome_lib.blocklist_no_aircheck[#biome_lib.blocklist_no_aircheck + 1] = { minp, maxp }
+end)
+
+-- "Play" them back, populating them with new stuff in the process
+
+minetest.register_globalstep(function(dtime)
+	if dtime < 0.2 and    -- don't attempt to populate if lag is already too high
+	  (#biome_lib.blocklist_aircheck > 0 or #biome_lib.blocklist_no_aircheck > 0) then
+		biome_lib.globalstep_start_time = minetest.get_us_time()
+		biome_lib.globalstep_runtime = 0
+		while (#biome_lib.blocklist_aircheck > 0 or #biome_lib.blocklist_no_aircheck > 0)
+		  and biome_lib.globalstep_runtime < 200000 do  -- 0.2 seconds, in uS.
+			if #biome_lib.blocklist_aircheck > 0 then
+				biome_lib:generate_block_with_air_checking()
+			end
+			if #biome_lib.blocklist_no_aircheck > 0 then
+				biome_lib:generate_block_no_aircheck()
+			end
+			biome_lib.globalstep_runtime = minetest.get_us_time() - biome_lib.globalstep_start_time
+		end
+	end
+end)
+
+-- Play out the entire log all at once on shutdown
+-- to prevent unpopulated map areas
+
+minetest.register_on_shutdown(function()
+	print("[biome_lib] Stand by, playing out the rest of the aircheck mapblock log")
+	print("(there are "..#biome_lib.blocklist_aircheck.." entries)...")
+	while true do
+		biome_lib:generate_block_with_air_checking(0.1)
+		if #biome_lib.blocklist_aircheck == 0 then return end
+	end
+end)
+
+minetest.register_on_shutdown(function()
+	print("[biome_lib] Stand by, playing out the rest of the no-aircheck mapblock log")
+	print("(there are "..#biome_lib.blocklist_aircheck.." entries)...")
+	while true do
+		biome_lib:generate_block_no_aircheck(0.1)
+		if #biome_lib.blocklist_no_aircheck == 0 then return end
+	end
+end)
+
+-- The spawning ABM
+
+function biome_lib:spawn_on_surfaces(sd,sp,sr,sc,ss,sa)
+
+	local biome = {}
+
+	if type(sd) ~= "table" then
+		biome.spawn_delay = sd	-- old api expects ABM interval param here.
+		biome.spawn_plants = {sp}
+		biome.avoid_radius = sr
+		biome.spawn_chance = sc
+		biome.spawn_surfaces = {ss}
+		biome.avoid_nodes = sa
+	else
+		biome = sd
+	end
+
+	if biome.spawn_delay*time_scale >= 1 then
+		biome.interval = biome.spawn_delay*time_scale
+	else
+		biome.interval = 1
+	end
+
+	biome_lib:set_defaults(biome)
+	biome.spawn_plants_count = #(biome.spawn_plants)
+
+	minetest.register_abm({
+		nodenames = biome.spawn_surfaces,
+		interval = biome.interval,
+		chance = biome.spawn_chance,
+		neighbors = biome.neighbors,
+		action = function(pos, node, active_object_count, active_object_count_wider)
+			local p_top = { x = pos.x, y = pos.y + 1, z = pos.z }	
+			local n_top = minetest.get_node(p_top)
+			local perlin_fertile_area = minetest.get_perlin(biome.seed_diff, perlin_octaves, perlin_persistence, perlin_scale)
+			local noise1 = perlin_fertile_area:get2d({x=p_top.x, y=p_top.z})
+			local noise2 = biome_lib.perlin_temperature:get2d({x=p_top.x, y=p_top.z})
+			local noise3 = biome_lib.perlin_humidity:get2d({x=p_top.x+150, y=p_top.z+50})
+			if noise1 > biome.plantlife_limit 
+			  and noise2 <= biome.temp_min
+			  and noise2 >= biome.temp_max
+			  and noise3 <= biome.humidity_min
+			  and noise3 >= biome.humidity_max
+			  and biome_lib:is_node_loaded(p_top) then
+				local n_light = minetest.get_node_light(p_top, nil)
+				if not (biome.avoid_nodes and biome.avoid_radius and minetest.find_node_near(p_top, biome.avoid_radius + math.random(-1.5,2), biome.avoid_nodes))
+				  and n_light >= biome.light_min
+				  and n_light <= biome.light_max
+				  and (not(biome.neighbors and biome.ncount) or #(minetest.find_nodes_in_area({x=pos.x-1, y=pos.y, z=pos.z-1}, {x=pos.x+1, y=pos.y, z=pos.z+1}, biome.neighbors)) > biome.ncount )
+				  and (not(biome.near_nodes and biome.near_nodes_count and biome.near_nodes_size) or #(minetest.find_nodes_in_area({x=pos.x-biome.near_nodes_size, y=pos.y-biome.near_nodes_vertical, z=pos.z-biome.near_nodes_size}, {x=pos.x+biome.near_nodes_size, y=pos.y+biome.near_nodes_vertical, z=pos.z+biome.near_nodes_size}, biome.near_nodes)) >= biome.near_nodes_count)
+				  and (not(biome.air_count and biome.air_size) or #(minetest.find_nodes_in_area({x=p_top.x-biome.air_size, y=p_top.y, z=p_top.z-biome.air_size}, {x=p_top.x+biome.air_size, y=p_top.y, z=p_top.z+biome.air_size}, "air")) >= biome.air_count)
+				  and pos.y >= biome.min_elevation
+				  and pos.y <= biome.max_elevation
+				  then
+					local walldir = biome_lib:find_adjacent_wall(p_top, biome.verticals_list, biome.choose_random_wall)
+					if biome.alt_wallnode and walldir then
+						if n_top.name == "air" then
+							minetest.set_node(p_top, { name = biome.alt_wallnode, param2 = walldir })
+						end
+					else
+						local currentsurface = minetest.get_node(pos).name
+						if currentsurface ~= "default:water_source"
+						  or (currentsurface == "default:water_source" and #(minetest.find_nodes_in_area({x=pos.x, y=pos.y-biome.depth_max-1, z=pos.z}, {x=pos.x, y=pos.y, z=pos.z}, {"default:dirt", "default:dirt_with_grass", "default:sand"})) > 0 )
+						  then
+							local rnd = math.random(1, biome.spawn_plants_count)
+							local plant_to_spawn = biome.spawn_plants[rnd]
+							local fdir = biome.facedir
+							if biome.random_facedir then
+								fdir = math.random(biome.random_facedir[1],biome.random_facedir[2])
+							end
+							if type(biome.spawn_plants) == "string" then
+								assert(loadstring(biome.spawn_plants.."(...)"))(pos)
+							elseif not biome.spawn_on_side and not biome.spawn_on_bottom and not biome.spawn_replace_node then
+								if n_top.name == "air" then
+									minetest.set_node(p_top, { name = plant_to_spawn, param2 = fdir })
+								end
+							elseif biome.spawn_replace_node then
+								minetest.set_node(pos, { name = plant_to_spawn, param2 = fdir })
+
+							elseif biome.spawn_on_side then
+								local onside = biome_lib:find_open_side(pos)
+								if onside then 
+									minetest.set_node(onside.newpos, { name = plant_to_spawn, param2 = onside.facedir })
+								end
+							elseif biome.spawn_on_bottom then
+								if minetest.get_node({x=pos.x, y=pos.y-1, z=pos.z}).name == "air" then
+									minetest.set_node({x=pos.x, y=pos.y-1, z=pos.z}, { name = plant_to_spawn, param2 = fdir} )
+								end
+							end
+						end
+					end
+				end
+			end
+		end
+	})
+end
+
+-- The growing ABM
+
+function biome_lib:grow_plants(opts)
+
+	local options = opts
+
+	options.height_limit = options.height_limit or 5
+	options.ground_nodes = options.ground_nodes or { "default:dirt_with_grass" }
+	options.grow_nodes = options.grow_nodes or { "default:dirt_with_grass" }
+	options.seed_diff = options.seed_diff or 0
+
+	if options.grow_delay*time_scale >= 1 then
+		options.interval = options.grow_delay*time_scale
+	else
+		options.interval = 1
+	end
+
+	minetest.register_abm({
+		nodenames = { options.grow_plant },
+		interval = options.interval,
+		chance = options.grow_chance,
+		action = function(pos, node, active_object_count, active_object_count_wider)
+			local p_top = {x=pos.x, y=pos.y+1, z=pos.z}
+			local p_bot = {x=pos.x, y=pos.y-1, z=pos.z}
+			local n_top = minetest.get_node(p_top)
+			local n_bot = minetest.get_node(p_bot)
+			local root_node = minetest.get_node({x=pos.x, y=pos.y-options.height_limit, z=pos.z})
+			local walldir = nil
+			if options.need_wall and options.verticals_list then
+				walldir = biome_lib:find_adjacent_wall(p_top, options.verticals_list, options.choose_random_wall)
+			end
+			if (n_top.name == "air" or n_top.name == "default:snow")
+			  and (not options.need_wall or (options.need_wall and walldir)) then
+				-- corner case for changing short junglegrass
+				-- to dry shrub in desert
+				if n_bot.name == options.dry_early_node and options.grow_plant == "junglegrass:short" then
+					minetest.set_node(pos, { name = "default:dry_shrub" })
+
+				elseif options.grow_vertically and walldir then
+					if biome_lib:search_downward(pos, options.height_limit, options.ground_nodes) then
+						minetest.set_node(p_top, { name = options.grow_plant, param2 = walldir})
+					end
+
+				elseif not options.grow_result and not options.grow_function then
+					minetest.remove_node(pos)
+
+				else
+					biome_lib:replace_object(pos, options.grow_result, options.grow_function, options.facedir, options.seed_diff)
+				end
+			end
+		end
+	})
+end
+
+-- Function to decide how to replace a plant - either grow it, replace it with
+-- a tree, run a function, or die with an error.
+
+function biome_lib:replace_object(pos, replacement, grow_function, walldir, seeddiff)
+	local growtype = type(grow_function)
+	if growtype == "table" then
+		minetest.remove_node(pos)
+		biome_lib:grow_tree(pos, grow_function)
+		return
+	elseif growtype == "function" then
+		local perlin_fertile_area = minetest.get_perlin(seeddiff, perlin_octaves, perlin_persistence, perlin_scale)
+		local noise1 = perlin_fertile_area:get2d({x=pos.x, y=pos.z})
+		local noise2 = biome_lib.perlin_temperature:get2d({x=pos.x, y=pos.z})
+		grow_function(pos,noise1,noise2,walldir)
+		return
+	elseif growtype == "string" then
+		local perlin_fertile_area = minetest.get_perlin(seeddiff, perlin_octaves, perlin_persistence, perlin_scale)
+		local noise1 = perlin_fertile_area:get2d({x=pos.x, y=pos.z})
+		local noise2 = biome_lib.perlin_temperature:get2d({x=pos.x, y=pos.z})
+		assert(loadstring(grow_function.."(...)"))(pos,noise1,noise2,walldir)
+		return
+	elseif growtype == "nil" then
+		minetest.set_node(pos, { name = replacement, param2 = walldir})
+		return
+	elseif growtype ~= "nil" and growtype ~= "string" and growtype ~= "table" then
+		error("Invalid grow function "..dump(grow_function).." used on object at ("..dump(pos)..")")
+	end
+end
+
+-- function to decide if a node has a wall that's in verticals_list{}
+-- returns wall direction of valid node, or nil if invalid.
+
+function biome_lib:find_adjacent_wall(pos, verticals, randomflag)
+	local verts = dump(verticals)
+	if randomflag then
+		local walltab = {}
+		
+		if string.find(verts, minetest.get_node({ x=pos.x-1, y=pos.y, z=pos.z   }).name) then walltab[#walltab + 1] = 3 end
+		if string.find(verts, minetest.get_node({ x=pos.x+1, y=pos.y, z=pos.z   }).name) then walltab[#walltab + 1] = 2 end
+		if string.find(verts, minetest.get_node({ x=pos.x  , y=pos.y, z=pos.z-1 }).name) then walltab[#walltab + 1] = 5 end
+		if string.find(verts, minetest.get_node({ x=pos.x  , y=pos.y, z=pos.z+1 }).name) then walltab[#walltab + 1] = 4 end
+
+		if #walltab > 0 then return walltab[math.random(1, #walltab)] end
+
+	else
+		if string.find(verts, minetest.get_node({ x=pos.x-1, y=pos.y, z=pos.z   }).name) then return 3 end
+		if string.find(verts, minetest.get_node({ x=pos.x+1, y=pos.y, z=pos.z   }).name) then return 2 end
+		if string.find(verts, minetest.get_node({ x=pos.x  , y=pos.y, z=pos.z-1 }).name) then return 5 end
+		if string.find(verts, minetest.get_node({ x=pos.x  , y=pos.y, z=pos.z+1 }).name) then return 4 end
+	end
+	return nil
+end
+
+-- Function to search downward from the given position, looking for the first
+-- node that matches the ground table.  Returns the new position, or nil if
+-- height limit is exceeded before finding it.
+
+function biome_lib:search_downward(pos, heightlimit, ground)
+	for i = 0, heightlimit do
+		if string.find(dump(ground), minetest.get_node({x=pos.x, y=pos.y-i, z = pos.z}).name) then
+			return {x=pos.x, y=pos.y-i, z = pos.z}
+		end
+	end
+	return false
+end
+
+function biome_lib:find_open_side(pos)
+	if minetest.get_node({ x=pos.x-1, y=pos.y, z=pos.z }).name == "air" then
+		return {newpos = { x=pos.x-1, y=pos.y, z=pos.z }, facedir = 2}
+	end
+	if minetest.get_node({ x=pos.x+1, y=pos.y, z=pos.z }).name == "air" then
+		return {newpos = { x=pos.x+1, y=pos.y, z=pos.z }, facedir = 3}
+	end
+	if minetest.get_node({ x=pos.x, y=pos.y, z=pos.z-1 }).name == "air" then
+		return {newpos = { x=pos.x, y=pos.y, z=pos.z-1 }, facedir = 4}
+	end
+	if minetest.get_node({ x=pos.x, y=pos.y, z=pos.z+1 }).name == "air" then
+		return {newpos = { x=pos.x, y=pos.y, z=pos.z+1 }, facedir = 5}
+	end
+	return nil
+end
+
+-- spawn_tree() on generate is routed through here so that other mods can hook
+-- into it.
+
+function biome_lib:generate_tree(pos, nodes_or_function_or_model)
+	minetest.spawn_tree(pos, nodes_or_function_or_model)
+end
+
+-- and this one's for the call used in the growing code
+
+function biome_lib:grow_tree(pos, nodes_or_function_or_model)
+	minetest.spawn_tree(pos, nodes_or_function_or_model)
+end
+
+-- Check for infinite stacks
+
+if minetest.get_modpath("unified_inventory") or not minetest.setting_getbool("creative_mode") then
+	biome_lib.expect_infinite_stacks = false
+else
+	biome_lib.expect_infinite_stacks = true
+end
+
+-- read a field from a node's definition
+
+function biome_lib:get_nodedef_field(nodename, fieldname)
+	if not minetest.registered_nodes[nodename] then
+		return nil
+	end
+	return minetest.registered_nodes[nodename][fieldname]
+end
+
+print("[Biome Lib] Loaded")
+
+minetest.after(0, function()
+	print("[Biome Lib] Registered a total of "..(#biome_lib.surfaceslist_aircheck)+(#biome_lib.surfaceslist_no_aircheck).." surface types to be evaluated, spread")
+	print("[Biome Lib] across "..#biome_lib.actionslist_aircheck.." actions with air-checking and "..#biome_lib.actionslist_no_aircheck.." actions without.")
+end)
+