don't nil-out the recheck list, just empty it.

since nothing much is normally found outside that range anyway

only enqueue blocks that are within that range, or within
the range specfied by all of the mods that make generate_plant() calls,
whichever covers more volume.

API.txt

@@ -112,9 +112,9 @@ biome = {
 	depth_max = num,	-- If the object spawns on top of a water source, the
 						-- water must be at most this deep.  Defaults to 1.
 	min_elevation = num, -- Surface must be at this altitude or higher to
-						-- spawn at all.  Defaults to -31000...
+						 -- spawn at all.  Defaults to -16 meters.
-	max_elevation = num, -- ...but must be no higher than this altitude.
+	max_elevation = num, -- Surface must be no higher than this altitude.
-						-- Defaults to +31000.
+						 -- Defaults to +48.
 	near_nodes = {table}, -- List of nodes that must be somewhere in the
 						-- vicinity in order for the plant to spawn. Can also
 						-- be a string with a single node name.  If not
@@ -270,8 +270,8 @@ biome = {
 	depth = num,		-- How deep/thick of a layer the spawned-on node must
 						-- be.  Typically used for water.
 	min_elevation = num, -- Minimum elevation in meters/nodes.  Defaults to
-						-- -31000 (unlimited).
+						-- -16 meters.
-	max_elevation = num, -- Max elevation.  Defaults to +31000 (unlimited).
+	max_elevation = num, -- Max elevation.  Defaults to +48m.
 	near_nodes = {table}, -- what nodes must be in the general vicinity of the
 						-- object being spawned.
 	near_nodes_size = num, -- how wide of a search area to look for the nodes
@@ -446,12 +446,22 @@ question is already loaded, or false if not.
 
 
 =====
-dbg(string)
+dbg(string, level)
 
 This is a simple debug output function which takes one string parameter.  It
 just checks if DEBUG is true and outputs the phrase "[Plantlife] " followed by
 the supplied string, via the print() function, if so.
 
+'level' is a number that, if supplied, dictates the lowest 'biome_lib_debug'
+can be set to in minetest.conf for this message to be displayed.  Both the
+default log level and the default message level are 0, thus always showing the
+supplied message.
+
+Although it's not set in stone, a good practice is to use a level of 0 (or
+just omit the value) for anything that generally important enough that it
+ought always be shown, 1 for errors, 2 for warnings, 3 for info, 4 for verbose
+spammy stuff.
+
 =====
 biome_lib:generate_tree(pos, treemodel)
 biome_lib:grow_tree(pos, treemodel)
@@ -597,34 +607,7 @@ Although this project was intended to be used with minetest_game, it can be
 configured to work with something else instead.  All you need to do is provide
 the names of the nodes in your game you want biome_lib's internals to use.
 
-Put these settings in your game's minetest.conf (or your client's own config,
+See settingtypes.txt for a list.  Any item listed there can be changed either
-if desired).  You'll need to set all of them.
+by adding it to your minetest.conf, or by using the "all settings" menu in
+Minetest, whatever's appropriate for your particular setup.
 
-biome_lib_default_grow_through_nodes
-	Comma-separated list of things that a spawned node is allowed to grow
-	through.  Air is always added to whatever you specify.
-	Default:  air, default:snow
-
-biome_lib_default_water_nodes
-	Comma-separated list of nodes that should be treated as water for the sake
-	of looking for neighboring "wet" ground.
-	Default: default:water_source, default:water_flowing,
-		default:river_water_source, default:river_water_flowing
-
-biome_lib_default_wet_surfaces
-	Comma-separated list of nodes that should be considered "wet" if one of
-	the aforementioned water nodes is nearby.
-	Default: default:dirt, default:dirt_with_grass, default:sand
-
-biome_lib_default_grow_nodes
-	Comma-separated list of nodes that something must be sitting on to be
-	able to actively change from one thing to another (such as a sapling
-	growing into a tree), to be used for ALL growable nodes, if the calling
-	mod doesn't provide its own lists.
-	Default: "default:dirt_with_grass"
-
-biome_lib_default_ground_nodes
-	Comma-separated list of nodes to use as the "root" of something that can
-	gradually climb up a wall, to be used for ALL such nodes, if the calling
-	mod doesn't provide its own lists.
-	Default: "default:dirt_with_grass"

README.md

@@ -25,4 +25,6 @@ It is primarily intended for mapgen v6, but it should work fine when used with m
 * biome_lib:find_valid_wall()
 * biome_lib:is_node_loaded()
 
-For a complete description of these functions as well as several of the internal variables within the mod, [read the API.txt document](https://raw.githubusercontent.com/minetest-mods/biome_lib/master/API.txt) included in this package.
+For a complete description of these functions as well as several of the internal variables within the mod, see `API.txt`.
+
+**Configuration:** This mod has several variables you can set in your `minetest.conf` to change things a bit, from the default nodes it uses, to the debug log level and the block queue behavior.  For a list with complete descriptions, see `settingtypes.txt`.

init.lua

@@ -4,12 +4,28 @@
 -- Splizard's snow mod.
 --
 
+biome_lib = {}
+
+-- Boilerplate to support localized strings if intllib mod is installed.
+local S
+if minetest.global_exists("intllib") then
+	if intllib.make_gettext_pair then
+		S = intllib.make_gettext_pair()
+	else
+		S = intllib.Getter()
+	end
+else
+	S = function(s) return s end
+end
+biome_lib.intllib = S
+
 -- Various settings - most of these probably won't need to be changed
 
-biome_lib = {}
 biome_lib.air = {name = "air"}
 
 biome_lib.block_log = {}
+biome_lib.block_recheck_list = {}
+biome_lib.run_block_recheck_list = false
 
 biome_lib.actionslist_aircheck = {}
 biome_lib.actionslist_no_aircheck = {}
@@ -17,6 +33,10 @@ biome_lib.actionslist_no_aircheck = {}
 biome_lib.surfaceslist_aircheck = {}
 biome_lib.surfaceslist_no_aircheck = {}
 
+-- the mapgen rarely creates useful surfaces outside this range, but mods can
+-- still specify a wider range if needed.
+biome_lib.mapgen_elevation_limit = { ["min"] = -16, ["max"] = 48 } 
+
 biome_lib.modpath = minetest.get_modpath("biome_lib")
 
 local function tableize(s)
@@ -54,27 +74,25 @@ biome_lib.default_wet_surfaces = c3 and tableize(c3) or {"default:dirt", "defaul
 biome_lib.default_ground_nodes = c4 and tableize(c4) or {"default:dirt_with_grass"}
 biome_lib.default_grow_nodes =   c5 and tableize(c5) or {"default:dirt_with_grass"}
 
--- Boilerplate to support localized strings if intllib mod is installed.
+biome_lib.debug_log_level = tonumber(minetest.settings:get("biome_lib_debug_log_level")) or 0
-local S
-if minetest.global_exists("intllib") then
-	if intllib.make_gettext_pair then
-		S = intllib.make_gettext_pair()
-	else
-		S = intllib.Getter()
-	end
-else
-	S = function(s) return s end
-end
-biome_lib.intllib = S
 
-local DEBUG = minetest.settings:get_bool("biome_lib_debug", false)
+local rr = tonumber(minetest.settings:get("biome_lib_queue_ratio")) or -200
+biome_lib.queue_ratio = 100 - rr
+biome_lib.entries_per_step = math.max(-rr, 1)
 
-function biome_lib:dbg(msg)
+-- the timer that manages the block timeout is in microseconds, but the timer
-	if DEBUG then
+-- that manages the queue wakeup call has to be in seconds, and works best if
-		print("[Biome Lib] "..msg)
+-- it takes a fraction of the block timeout interval.
-		minetest.log("verbose", "[Biome Lib] "..msg)
+
-	end
+local t = tonumber(minetest.settings:get("biome_lib_block_timeout")) or 300
-end
+
+biome_lib.block_timeout = t * 1000000
+
+-- we don't want the wakeup function to trigger TOO often,
+-- in case the user's block timeout setting is really low
+biome_lib.block_queue_wakeup_time = math.min(t/2, math.max(20, t/10))
+
+local time_speed = tonumber(minetest.settings:get("time_speed"))
 
 biome_lib.plantlife_seed_diff = 329 -- needs to be global so other mods can see it
 
@@ -93,7 +111,6 @@ local humidity_persistence = 0.5
 local humidity_scale = 250
 
 local time_scale = 1
-local time_speed = tonumber(minetest.settings:get("time_speed"))
 
 if time_speed and time_speed > 0 then
 	time_scale = 72 / time_speed
@@ -106,6 +123,14 @@ biome_lib.perlin_humidity = PerlinNoise(humidity_seeddiff, humidity_octaves, hum
 
 -- Local functions
 
+function biome_lib.dbg(msg, level)
+	local l = tonumber(level) or 0
+	if biome_lib.debug_log_level >= l then
+		print("[Biome Lib] "..msg)
+		minetest.log("verbose", "[Biome Lib] "..msg)
+	end
+end
+
 local function get_biome_data(pos, perlin_fertile)
 	local fertility = perlin_fertile:get_2d({x=pos.x, y=pos.z})
 
@@ -132,8 +157,8 @@ end
 
 function biome_lib:set_defaults(biome)
 	biome.seed_diff = biome.seed_diff or 0
-	biome.min_elevation = biome.min_elevation or -31000
+	biome.min_elevation = biome.min_elevation or biome_lib.mapgen_elevation_limit.min
-	biome.max_elevation = biome.max_elevation or 31000
+	biome.max_elevation = biome.max_elevation or biome_lib.mapgen_elevation_limit.max
 	biome.temp_min = biome.temp_min or 1
 	biome.temp_max = biome.temp_max or -1
 	biome.humidity_min = biome.humidity_min or 1
@@ -176,17 +201,20 @@ function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
 	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))
+		biome_lib.dbg("Warning: Ignored registration for undefined spawn node: "..dump(nodes_or_function_or_model), 2)
 		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))
+		biome_lib.dbg("Warning: Registered function call using deprecated string method: "..dump(nodes_or_function_or_model), 2)
 	end
 
+	biome_lib.mapgen_elevation_limit.min = math.min(biomedef.min_elevation or 0, biome_lib.mapgen_elevation_limit.min)
+	biome_lib.mapgen_elevation_limit.max = math.max(biomedef.max_elevation or 0, biome_lib.mapgen_elevation_limit.max)
+
 	if biomedef.check_air == false then 
-		biome_lib:dbg("Register no-air-check mapgen hook: "..dump(nodes_or_function_or_model))
+		biome_lib.dbg("Register no-air-check mapgen hook: "..dump(nodes_or_function_or_model), 3)
 		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
@@ -195,7 +223,7 @@ function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
 					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))
+				biome_lib.dbg("Warning: Ignored no-air-check registration for undefined surface node: "..dump(s), 2)
 			end
 		else
 			for i = 1, #biomedef.surface do
@@ -205,12 +233,12 @@ function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
 						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))
+					biome_lib.dbg("Warning: Ignored no-air-check registration for undefined surface node: "..dump(s), 2)
 				end
 			end
 		end
 	else
-		biome_lib:dbg("Register with-air-checking mapgen hook: "..dump(nodes_or_function_or_model))
+		biome_lib.dbg("Register with-air-checking mapgen hook: "..dump(nodes_or_function_or_model), 3)
 		biome_lib.actionslist_aircheck[#biome_lib.actionslist_aircheck + 1] = { biomedef, nodes_or_function_or_model }
 		local s = biomedef.surface
 		if type(s) == "string" then
@@ -219,7 +247,7 @@ function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
 					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))
+				biome_lib.dbg("Warning: Ignored with-air-checking registration for undefined surface node: "..dump(s), 2)
 			end
 		else
 			for i = 1, #biomedef.surface do
@@ -229,7 +257,7 @@ function biome_lib:register_generate_plant(biomedef, nodes_or_function_or_model)
 						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))
+					biome_lib.dbg("Warning: Ignored with-air-checking registration for undefined surface node: "..dump(s), 2)
 				end
 			end
 		end
@@ -381,7 +409,7 @@ function biome_lib.populate_surfaces(biome, nodes_or_function_or_model, snodes,
 				if objtype == "table" then
 					if nodes_or_function_or_model.axiom then
 						biome_lib:generate_tree(p_top, nodes_or_function_or_model)
-						biome_lib:dbg("An L-tree was spawned at "..minetest.pos_to_string(p_top))
+						biome_lib.dbg("An L-tree was spawned at "..minetest.pos_to_string(p_top), 4)
 						spawned = true
 					else
 						local fdir = nil
@@ -390,7 +418,7 @@ function biome_lib.populate_surfaces(biome, nodes_or_function_or_model, snodes,
 						end
 						local n=nodes_or_function_or_model[math.random(#nodes_or_function_or_model)]
 						minetest.swap_node(p_top, { name = n, param2 = fdir })
-						biome_lib:dbg("Node \""..n.."\" was randomly picked from a list and placed at "..minetest.pos_to_string(p_top))
+						biome_lib.dbg("Node \""..n.."\" was randomly picked from a list and placed at "..minetest.pos_to_string(p_top), 4)
 						spawned = true
 					end
 				elseif objtype == "string" and
@@ -400,18 +428,18 @@ function biome_lib.populate_surfaces(biome, nodes_or_function_or_model, snodes,
 						fdir = math.random(biome.random_facedir[1], biome.random_facedir[2])
 					end
 					minetest.swap_node(p_top, { name = nodes_or_function_or_model, param2 = fdir })
-					biome_lib:dbg("Node \""..nodes_or_function_or_model.."\" was placed at "..minetest.pos_to_string(p_top))
+					biome_lib.dbg("Node \""..nodes_or_function_or_model.."\" was placed at "..minetest.pos_to_string(p_top), 4)
 					spawned = true
 				elseif objtype == "function" then
 					nodes_or_function_or_model(pos)
-					biome_lib:dbg("A function was run on surface node at "..minetest.pos_to_string(pos))
+					biome_lib.dbg("A function was run on surface node at "..minetest.pos_to_string(pos), 4)
 					spawned = true
 				elseif objtype == "string" and pcall(loadstring(("return %s(...)"):
 					format(nodes_or_function_or_model)),pos) then
 					spawned = true
-					biome_lib:dbg("An obsolete string-specified function was run on surface node at "..minetest.pos_to_string(p_top))
+					biome_lib.dbg("An obsolete string-specified function was run on surface node at "..minetest.pos_to_string(p_top), 4)
 				else
-					biome_lib:dbg("Warning: Ignored invalid definition for object "..dump(nodes_or_function_or_model).." that was pointed at {"..dump(pos).."}")
+					biome_lib.dbg("Warning: Ignored invalid definition for object "..dump(nodes_or_function_or_model).." that was pointed at {"..dump(pos).."}", 2)
 				end
 			else
 				tries = tries + 1
@@ -439,9 +467,6 @@ local function confirm_block_surroundings(p)
 	return true
 end
 
-biome_lib.block_recheck_list = {}
-biome_lib.run_block_recheck_list = false
-
 function biome_lib.generate_block(shutting_down)
 
 	if shutting_down then
@@ -471,9 +496,12 @@ function biome_lib.generate_block(shutting_down)
 	local pos_hash = 	minetest.hash_node_position(minp)
 
 	if not biome_lib.pos_hash then -- we need to read the maplock and get the surfaces list
+		local now = minetest.get_us_time()
 		biome_lib.pos_hash = {}
+		minetest.load_area(minp)
 		if not confirm_block_surroundings(minp)
-		  and not shutting_down then -- if any neighbors appear not to be loaded, skip this block for now
+		  and not shutting_down
+		  and (blocklog[1][4] + biome_lib.block_timeout) > now then -- if any neighbors appear not to be loaded and the block hasn't expired yet, defer it
 
 			if biome_lib.run_block_recheck_list then
 				biome_lib.block_log[#biome_lib.block_log + 1] = table.copy(biome_lib.block_recheck_list[1])
@@ -483,25 +511,30 @@ function biome_lib.generate_block(shutting_down)
 				table.remove(biome_lib.block_log, 1)
 			end
 			biome_lib.pos_hash = nil
-				biome_lib:dbg("Mapblock at "..minetest.pos_to_string(minp)..
+				biome_lib.dbg("Mapblock at "..minetest.pos_to_string(minp)..
-					" had a neighbor not fully emerged, skipped it for now.")
+					" had a neighbor not fully emerged, skipped it for now.", 4)
 			return
 		else
 			biome_lib.pos_hash.surface_node_list = airflag
 				and minetest.find_nodes_in_area_under_air(minp, maxp, biome_lib.surfaceslist_aircheck)
 				or minetest.find_nodes_in_area(minp, maxp, biome_lib.surfaceslist_no_aircheck)
+			if #biome_lib.pos_hash.surface_node_list == 0 then
+				biome_lib.dbg("Mapblock at "..minetest.pos_to_string(minp).." dequeued:  no detected surfaces.", 4)
+				table.remove(blocklog, 1)
+				biome_lib.pos_hash = nil
+				return
+			else
 				biome_lib.pos_hash.action_index = 1
-			if #biome_lib.pos_hash.surface_node_list > 0 then
+				biome_lib.dbg("Mapblock at "..minetest.pos_to_string(minp)..
-				biome_lib:dbg("Mapblock at "..minetest.pos_to_string(minp)..
 					" has "..#biome_lib.pos_hash.surface_node_list..
-					" surface nodes to work on (airflag="..dump(airflag)..")")
+					" surface nodes to work on (airflag="..dump(airflag)..")", 4)
 			end
 		end
 	elseif not (airflag and biome_lib.actionslist_aircheck[biome_lib.pos_hash.action_index])
 	  and not (not airflag and biome_lib.actionslist_no_aircheck[biome_lib.pos_hash.action_index]) then
 		-- the block is finished, remove it
 		if #biome_lib.pos_hash.surface_node_list > 0 then
-			biome_lib:dbg("Deleted mapblock "..minetest.pos_to_string(minp).." from the block log")
+			biome_lib.dbg("Deleted mapblock "..minetest.pos_to_string(minp).." from the block log", 4)
 		end
 		table.remove(blocklog, 1)
 		biome_lib.pos_hash = nil
@@ -526,49 +559,93 @@ function biome_lib.generate_block(shutting_down)
 			end
 		end
 		if added > 0 then
-			biome_lib:dbg("biome_lib.populate_surfaces ran on mapblock at "..
+			biome_lib.dbg("biome_lib.populate_surfaces ran on mapblock at "..
 				minetest.pos_to_string(minp)..".  Entry #"..
-				(biome_lib.pos_hash.action_index-1).." added "..added.." items.")
+				(biome_lib.pos_hash.action_index-1).." added "..added.." items.", 4)
 		end
 	end
 end
 
 -- "Play" them back, populating them with new stuff in the process
 
-local rr = tonumber(minetest.settings:get("biome_lib_queue_run_ratio")) or -100
-
-biome_lib.queue_run_ratio = 100 - rr
-biome_lib.entries_per_step = math.max(-rr, 1)
-
 minetest.register_globalstep(function(dtime)
 	if not biome_lib.block_log[1] then return end -- the block log is empty
 
-	if math.random(100) > biome_lib.queue_run_ratio then return end
+	if math.random(100) > biome_lib.queue_ratio then return end
 	for s = 1, biome_lib.entries_per_step do
 		biome_lib.generate_block()
 	end
 end)
 
+-- Periodically wake-up the queue to give old blocks a chance to time-out
+-- if the player isn't currently exploring (i.e. they're just playing in one area)
+
+function biome_lib.wake_up_queue()
+	if #biome_lib.block_recheck_list > 1
+	  and #biome_lib.block_log == 0 then
+		biome_lib.block_log[#biome_lib.block_log + 1] =
+			table.copy(biome_lib.block_recheck_list[#biome_lib.block_recheck_list])
+		biome_lib.block_recheck_list[#biome_lib.block_recheck_list] = nil
+		biome_lib.run_block_recheck_list = true
+		biome_lib.dbg("Woke-up the map queue to give old blocks a chance to time-out.", 3)
+	end
+	minetest.after(biome_lib.block_queue_wakeup_time, biome_lib.wake_up_queue)
+end
+
+biome_lib.wake_up_queue()
+
 -- Play out the entire log all at once on shutdown
 -- to prevent unpopulated map areas
 
+local function format_time(t)
+	if t > 59999999 then
+		return os.date("!%M minutes and %S seconds", math.ceil(t/1000000))
+	else
+		return os.date("!%S seconds", math.ceil(t/1000000))
+	end
+end
+
+function biome_lib.check_remaining_time()
+	if minetest.get_us_time() > (biome_lib.shutdown_last_timestamp + 10000000) then -- report progress every 10s
+		biome_lib.shutdown_last_timestamp = minetest.get_us_time()
+
+		local entries_remaining = #biome_lib.block_log + #biome_lib.block_recheck_list
+
+		local total_purged = biome_lib.starting_count - entries_remaining
+		local elapsed_time = biome_lib.shutdown_last_timestamp - biome_lib.shutdown_start_time
+		biome_lib.dbg(string.format("%i entries, approximately %s remaining.",
+			entries_remaining, format_time(elapsed_time/total_purged * entries_remaining)))
+	end
+end
+
 minetest.register_on_shutdown(function()
-	if #biome_lib.block_log + #biome_lib.block_recheck_list == 0 then
+	biome_lib.shutdown_start_time = minetest.get_us_time()
+	biome_lib.shutdown_last_timestamp = minetest.get_us_time()+1
+
+	biome_lib.starting_count = #biome_lib.block_log + #biome_lib.block_recheck_list
+
+	if biome_lib.starting_count == 0 then
 		return
 	end
 
-	print("[biome_lib] Stand by, playing out the rest of the mapblock log")
+	biome_lib.dbg("Stand by, purging the mapblock log "..
-	print("(there are "..(#biome_lib.block_log + #biome_lib.block_recheck_list).." entries)...")
+		"(there are "..biome_lib.starting_count.." entries) ...", 0)
+
 	while #biome_lib.block_log > 0 do
 		biome_lib.generate_block(true)
+		biome_lib.check_remaining_time()
 	end
 
 	if #biome_lib.block_recheck_list > 0 then
 		biome_lib.block_log = table.copy(biome_lib.block_recheck_list)
+		biome_lib.block_recheck_list = {}
 		while #biome_lib.block_log > 0 do
 			biome_lib.generate_block(true)
+			biome_lib.check_remaining_time()
 		end
 	end
+	biome_lib.dbg("Log purge completed after "..
+		format_time(minetest.get_us_time() - biome_lib.shutdown_start_time)..".", 0)
 end)
 
 -- The spawning ABM
@@ -761,24 +838,36 @@ function biome_lib:get_nodedef_field(nodename, fieldname)
 	return minetest.registered_nodes[nodename][fieldname]
 end
 
-if DEBUG then
+if biome_lib.debug_log_level >= 3 then
 	biome_lib.last_count = 0
 
 	function biome_lib.show_pending_block_count()
 		if biome_lib.last_count ~= #biome_lib.block_log then
-			biome_lib:dbg("Pending block count: "..(#biome_lib.block_log + #biome_lib.block_recheck_list))
+			biome_lib.dbg(string.format("Pending block counts - ready to process: %-8icurrently deferred: %i",
+				#biome_lib.block_log, #biome_lib.block_recheck_list), 3)
 			biome_lib.last_count = #biome_lib.block_log
+			biome_lib.queue_idle_flag = false
+		elseif not biome_lib.queue_idle_flag then
+			if #biome_lib.block_recheck_list > 0 then
+				biome_lib.dbg("Mapblock queue only contains blocks that can't yet be processed.",  3)
+				biome_lib.dbg("Idling the queue until new blocks arrive or the next wake-up call occurs.",  3)
+			else
+				biome_lib.dbg("Mapblock queue has run dry.",  3)
+				biome_lib.dbg("Idling the queue until new blocks arrive.",  3)
+			end
+			biome_lib.queue_idle_flag = true
 		end
 		minetest.after(1, biome_lib.show_pending_block_count)
 	end
 
 	biome_lib.show_pending_block_count()
-
-	minetest.after(0, function()
-		print("Registered a total of "..(#biome_lib.surfaceslist_aircheck)+(#biome_lib.surfaceslist_no_aircheck).." surface types to be evaluated, spread")
-		print("across "..#biome_lib.actionslist_aircheck.." actions with air-checking and "..#biome_lib.actionslist_no_aircheck.." actions without.")
-	end)
-
 end
 
-print("[Biome Lib] Loaded")
+minetest.after(0, function()
+	biome_lib.dbg("Registered a total of "..(#biome_lib.surfaceslist_aircheck)+(#biome_lib.surfaceslist_no_aircheck).." surface types to be evaluated, spread", 0)
+	biome_lib.dbg("across "..#biome_lib.actionslist_aircheck.." actions with air-checking and "..#biome_lib.actionslist_no_aircheck.." actions without.", 0)
+	biome_lib.dbg("within an elevation range of "..biome_lib.mapgen_elevation_limit.min.." and "..biome_lib.mapgen_elevation_limit.max.." meters.", 0)
+
+end)
+
+biome_lib.dbg("[Biome Lib] Loaded", 0)

search_functions.lua

@@ -56,19 +56,28 @@ end
 -- split into individual mapblocks to reduce lag
 
 minetest.register_on_generated(function(minp, maxp, blockseed)
-	for x = 0, 4 do
+	local timestamp = minetest.get_us_time()
-		local minx = minp.x + x*16
 	for y = 0, 4 do
 		local miny = minp.y + y*16
+
+		if miny >= biome_lib.mapgen_elevation_limit.min
+		  and (miny + 15) <= biome_lib.mapgen_elevation_limit.max then
+
+			for x = 0, 4 do
+				local minx = minp.x + x*16
+
 				for z = 0, 4 do
 					local minz = minp.z + z*16
 
 					local bmin = {x=minx, y=miny, z=minz}
 					local bmax = {x=minx + 15, y=miny + 15, z=minz + 15}
-				biome_lib.block_log[#biome_lib.block_log + 1] = { bmin, bmax, true }
+					biome_lib.block_log[#biome_lib.block_log + 1] = { bmin, bmax, true, timestamp }
-				biome_lib.block_log[#biome_lib.block_log + 1] = { bmin, bmax, false }
+					biome_lib.block_log[#biome_lib.block_log + 1] = { bmin, bmax, false, timestamp }
 				end
 			end
+		else
+			biome_lib.dbg("Did not enqueue mapblocks at elevation "..miny.."m, they're out of range of any generate_plant() calls.", 4)
+		end
 	end
 	biome_lib.run_block_recheck_list = true
 end)

settingtypes.txt

@@ -0,0 +1,48 @@
+# Comma-separated list of things that a spawned node is allowed to grow
+# through.  Air is always added to whatever else you specify here.
+biome_lib_default_grow_through_nodes (List of things a plant can grow through) string default:snow
+
+# Comma-separated list of nodes that should be treated as water or water-like
+# for the sake of looking for neighboring wet ground.
+biome_lib_default_water_nodes (List of "water-like" sources) string default:water_source,default:water_flowing,default:river_water_source,default:river_water_flowing
+
+# Comma-separated list of nodes that should be considered "wet" if one of
+# the configured "water-like" sources is nearby.
+biome_lib_default_wet_surfaces (List of "wet" nodes) string default:dirt,default:dirt_with_grass,default:sand
+
+# Comma-separated list of nodes that something must be sitting on to be
+# able to actively change from one thing to another (such as a sapling
+# growing into a tree), to be used if the mod that added that growable
+# thing didn't provide its own list of suitable surfaces.
+biome_lib_default_grow_nodes (List of default surfaces a plant can thrive on) string default:dirt_with_grass
+
+# Comma-separated list of nodes to use as the "root" of something that can
+# gradually climb up a wall (such as ivy), to be used if the mod that added
+# the climing thing didn't provide its own list.
+biome_lib_default_ground_nodes (List of default root nodes) string default:dirt_with_grass
+
+# biome_lib divides its workload into "actions", as dictated by the sum
+# total of all mods that use it, and this sets how much of that work is done
+# per globalstep tick.  If positive, a single action is executed on that
+# percentage of ticks, on average. If negative, it becomes positive, and
+# that many actions are executed on every single tick, skipping none.
+# More negative means more throughput, at the expense of lag.  On fast PC's,
+# a setting of between -500 and -2000 might be good.
+biome_lib_queue_ratio (Queue run ratio) int -200
+
+# Minetest's map generator allows neighboring areas to overflow into one
+# another, to create smooth terrain, but it often hands the map blocks that
+# comprise those areas to Lua (and hence, to biome_lib) before that overflow
+# function happens, which causes the mapgen to overwrite whatever Lua does
+# to them.  This setting (in seconds) makes biome_lib wait before adding its
+# normal output to those map blocks, to give the engine plenty of time to
+# run that overflow feature first.
+biome_lib_block_timeout (Deferred block timeout) int 300
+
+# This does just what it sounds like - it shows all debug output that's sent
+# with a level equal to or greater than this value.  A setting of 0 shows only
+# the bare necessities, such as the startup and shutdown messages, 1 adds
+# internal non-fatal errors to what's shown, 2 adds warnings, 3 adds other
+# basic info, 4 adds all the verbose debugging spew. 3 is perhaps the most
+# useful setting.
+biome_lib_debug_log_level (Debug log level) int 0