656 lines
29 KiB
Text
656 lines
29 KiB
Text
This document describes the Plantlife mod API.
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Last revision: 2021-04-20
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=========
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Functions
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=========
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There are two main functions defined by this mod:
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biome_lib.register_active_spawner()
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biome_lib.register_on_generate()
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There are also several internal, helper functions that can be called if so
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desired, but they are not really intended for use by other mods and may change
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at any time. They are briefly described below these main functions, but see
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init.lua for details.
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Most functions in biome_lib are either declared locally or kept within its
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own namespace to avoid collisions/conflicts with other mods.
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=====
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biome_lib.register_active_spawner(biome)
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biome_lib.register_active_spawner(sdelay, splant, sradius, schance, ssurface, savoid)
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This first function is an ABM-based spawner function originally created as
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part of Ironzorg's flowers mod. It has since been largely extended and
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expanded. There are two ways to call this function: You can either pass it
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several individual string and number parameters to use the legacy interface,
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or you can pass a single biome definition as a table, with all of your options
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spelled out nicely. This is the preferred method.
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When used with the legacy interface, you must specify the parameters exactly
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in order, with the first five being mandatory (even if some are set to nil),
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and the last one being optional:
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sdelay: The value passed to the ABM's interval parameter, in seconds.
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splant: The node name of the item to spawn (e.g.
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"flowers:flower_rose"). A plant will of course only be
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spawned if the node about to be replaced is air.
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sradius: Don't spawn within this many nodes of the avoid items
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mentioned below. If set to nil, this check is skipped.
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schance: The value passed to the ABM's chance parameter, normally in
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the 10-100 range (1-in-X chance of operating on a given node)
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ssurface: String with the name of the node on which to spawn the plant
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in question, such as "default:sand" or
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"default:dirt_with_grass". It is not recommended to put air,
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stone, or plain dirt here if you can use some other node, as
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doing so will cause the engine to process potentially large
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numbers of such nodes when deciding when to execute the ABM
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and where it should operate.
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savoid: Table with a list of groups and/or node names to avoid when
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spawning the plant, such as {"group:flowers", "default:tree"}.
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When passed a table as the argument, and thus using the modern calling method,
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you must pass a number of arguments in the form of an ordinary keyed-value
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table. Below is a list of everything supported by this function:
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biome = {
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spawn_plants = something, -- [*] String or table; see below.
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spawn_delay = number, -- same as sdelay, above.
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spawn_chance = number, -- same as schance, above.
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spawn_surfaces = {table}, -- List of node names on which the plants
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-- should be spawned. As with the single-node "ssurface"
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-- option in the legacy API, you should not put stone, air,
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-- etc. here.
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---- From here down are a number of optional parameters. You will
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---- most likely want to use at least some of these to limit how and
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---- where your objects are spawned.
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label = string, -- set this to identify the ABM for Minetest's profiler
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avoid_nodes = {table}, -- same meaning as savoid, above
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avoid_radius = num, -- same as sradius
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seed_diff = num, -- The Perlin seed difference value passed to the
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-- minetest.get_perlin() function. Used along with
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-- the global Perlin controls below to create the
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-- "biome" in which the plants will spawn. Defaults
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-- to 0 if not provided.
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light_min = num, -- Minimum amount of light necessary to make a plant
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-- spawn. Defaults to 0.
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light_max = num, -- Maximum amount of light needed to spawn. Defaults
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-- to the engine's MAX_LIGHT value of 14.
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neighbors = {table}, -- List of neighboring nodes that need to be
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-- immediately next to the node the plant is about to
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-- spawn on. Can also be a string with a single node
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-- name. It is both passed to the ABM as the
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-- "neighbors" parameter, and is used to manually
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-- check the adjacent nodes. It only takes one of
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-- these for the spawn routine to mark the target as
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-- spawnable. Defaults to nil (ignored).
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ncount = num, -- There must be at least this many of the above
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-- neighbors in the eight spaces immediately
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-- surrounding the node the plant is about to spawn on
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-- for it to happen. If not provided, this check is
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-- disabled.
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facedir = num, -- The value passed to the param2 variable when adding
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-- the node to the map. Defaults to 0. Be sure that
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-- the value you use here (and the range thereof) is
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-- appropriate for the type of node you're spawning.
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random_facedir = {table}, -- If set, the table should contain two values.
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-- If they're both provided, the spawned plant will be
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-- given a random facedir value in the range specified
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-- by these two numbers. Overrides the facedir
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-- parameter above, if it exists. Use {0,3} if you
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-- want the full range for wallmounted nodes, or {2,5}
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-- for most everything else, or any other pair of
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-- numbers appropriate for the node you want to spawn.
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depth_max = num, -- If the object spawns on top of a water source, the
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-- water must be at most this deep. Defaults to 1.
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min_elevation = num, -- Surface must be at this altitude or higher to
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-- spawn at all. Defaults to -16 meters.
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max_elevation = num, -- Surface must be no higher than this altitude.
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-- Defaults to +48.
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near_nodes = {table}, -- List of nodes that must be somewhere in the
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-- vicinity in order for the plant to spawn. Can also
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-- be a string with a single node name. If not
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-- provided, this check is disabled.
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near_nodes_size = num, -- How large of an area to check for the above
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-- node. Specifically, this checks a flat, horizontal
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-- area centered on the node to be spawned on.
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-- Defaults to 0, but is ignored if the above
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-- near_nodes value is not set.
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near_nodes_vertical = num, -- Used with the size value above, this extends
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-- the vertical range of the near nodes search.
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-- Basically, this turns the flat region described
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-- above into a cuboid region. The area to be checked
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-- will extend this high and this low above/below the
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-- target node, centered thereon. Defaults to 1 (only
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-- check the layer above, the layer at, and the layer
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-- below the target node), but is ignored if
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-- near_nodes is not set.
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near_nodes_count = num, -- How many of the above nodes must be within that
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-- radius. Defaults to 1 but is ignored if near_nodes
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-- isn't set. Bear in mind that the total area to be
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-- checked is equal to:
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-- (near_nodes_size^2)*near_nodes_vertical*2
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-- For example, if size is 10 and vertical is 4, then
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-- the area is (10^2)*8 = 800 nodes in size, so you'll
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-- want to make sure you specify a value appropriate
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-- for the size of the area being tested.
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air_size = num, -- How large of an area to check for air above and
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-- around the target. If omitted, only the space
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-- above the target is checked. This does not check
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-- for air at the sides or below the target.
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air_count = num, -- How many of the surrounding nodes need to be air
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-- for the above check to return true. If omitted,
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-- only the space above the target is checked.
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plantlife_limit = num, -- The value compared against the generic "plants
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-- can grow here" Perlin noise layer. Smaller numbers
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-- result in more abundant plants. Range of -1 to +1,
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-- with values in the range of about 0 to 0.5 being
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-- most useful. Defaults to 0.1.
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temp_min = num, -- Minimum temperature needed for the desired object
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-- to spawn. This is a 2d Perlin value, which has an
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-- inverted range of +1 to -1. Larger values
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-- represent *colder* temperatures, so this value is
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-- actually the upper end of the desired Perlin range.
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-- See the temperature map section at the bottom of
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-- this document for details on how these values work.
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-- Defaults to +1 (unlimited coldness).
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temp_max = num, -- Maximum temperature/lower end of the Perlin range.
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-- Defaults to -1 (unlimited heat).
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humidity_min = num, -- Minimum humidity for the plant to spawn in. Like
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-- the temperature map, this is a Perlin value where
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-- lower numbers mean more humidity in the area.
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-- Defaults to +1 (0% humidity).
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humidity_max = num, -- Maximum humidity for the plant to spawn at.
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-- Defaults to -1 (100% humidity).
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verticals_list = {table}, -- List of nodes that should be considered to be
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-- natural walls.
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alt_wallnode = "string", -- If specified, this node will be substituted in
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-- place of the plant(s) defined by spawn_plants
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-- above, if the spawn target has one or more adjacent
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-- walls. In such a case, the two above facedir
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-- parameters will be ignored.
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spawn_on_side = bool, -- Set this to true to immediately spawn the node on
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-- one side of the target node rather than the top.
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-- The code will search for an airspace to the side of
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-- the target, then spawn the plant at the first one
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-- found. The above facedir and random_facedir
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-- parameters are ignored in this case. If the above
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-- parameters for selecting generic wall nodes are
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-- provided, this option is ignored. Important note:
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-- the facedir values assigned by this option only
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-- make sense with wallmounted nodes (nodes which
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-- don't use facedir won't be affected).
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choose_random_wall = bool, -- if set to true, and searching for walls is
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-- being done, just pick any random wall if there is
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-- one, rather than returning the first one.
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spawn_on_bottom = bool, -- If set to true, spawn the object below the
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-- target node instead of above it. The above
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-- spawn_on_side variable takes precedence over this
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-- one if both happen to be true. When using this
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-- option with the random facedir function above, the
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-- values given to the facedir parameter are for
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-- regular nodes, not wallmounted.
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spawn_replace_node = bool, -- If set to true, the target node itself is
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-- replaced by the spawned object. Overrides the
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-- spawn_on_bottom and spawn_on_side settings.
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}
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[*] spawn_plants must be either a table or a string. If it's a table, the
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values therein are treated as a list of nodenames to pick from randomly on
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each application of the ABM code. The more nodes you can pack into this
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parameter to avoid making too many calls to this function, the lower the CPU
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load will likely be.
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You can also specify a string containing the name of a function to execute.
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In this case, the function will be passed a single position parameter
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indicating where the function should place the desired object, and the checks
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for spawning on top vs. sides vs. bottom vs. replacing the target node will be
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skipped.
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By default, if a biome node, size, and count are not defined, the biome
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checking is disabled. Same holds true for the nneighbors bit above that.
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=====
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biome_lib.register_on_generate(biome, nodes_or_function_or_treedef)
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To register an object to be spawned at mapgen time rather than via an ABM,
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call this function with two parameters: a table with your object's biome
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information, and a string, function, or table describing what to do if the
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engine finds a suitable surface node (see below).
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The biome table contains quite a number of options, though there are fewer
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here than are available in the ABM-based spawner, as some stuff doesn't make
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sense at map-generation time.
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biome = {
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surface = something, -- What node(s). May be a string such as
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-- "default:dirt_with_grass" or a table with
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-- multiple such entries.
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---- Everything else is optional, but you'll definitely want to use
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---- some of these other fields to limit where and under what
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---- conditions the objects are spawned.
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below_nodes = {table}, -- List of nodes that must be below the target
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-- node. Useful in snow biomes to keep objects from
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-- spawning in snow that's on the wrong surface for
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-- that object.
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avoid_nodes = {table}, -- List of nodes to avoid when spawning. Groups are
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-- not supported here.
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avoid_radius = num, -- How much distance to leave between the object to be
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-- added and the objects to be avoided. If this or
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-- the avoid_nodes value is nil/omitted, this check is
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-- skipped. Avoid using excessively large radii.
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rarity = num, -- How rare should this object be in its biome? Larger
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-- values make objects more rare, via:
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-- math.random(1,100) > this
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max_count = num, -- The absolute maximum number of your object that
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-- should be allowed to spawn in a 5x5x5 mapblock area
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-- (80x80x80 nodes). Defaults to 5, but be sure you
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-- set this to some reasonable value depending on your
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-- object and its size if 5 is insufficient.
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seed_diff = num, -- Perlin seed-diff value. Defaults to 0, which
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-- causes the function to inherit the global value of
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-- 329.
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neighbors = {table}, -- What ground nodes must be right next to and at the
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-- same elevation as the node to be spawned on.
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ncount = num, -- At least this many of the above nodes must be next
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-- to the node to spawn on. Any value greater than 8
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-- will probably cause the code to never spawn
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-- anything. Defaults to 0.
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depth = num, -- How deep/thick of a layer the spawned-on node must
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-- be. Typically used for water.
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min_elevation = num, -- Minimum elevation in meters/nodes. Defaults to
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-- -16 meters.
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max_elevation = num, -- Max elevation. Defaults to +48m.
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near_nodes = {table}, -- what nodes must be in the general vicinity of the
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-- object being spawned.
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near_nodes_size = num, -- how wide of a search area to look for the nodes
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-- in that list.
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near_nodes_vertical = num, -- How high/low of an area to search from the
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-- target node.
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near_nodes_count = num, -- at least this many of those nodes must be in
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-- the area.
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plantlife_limit = num, -- The value compared against the generic "plants
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-- can grow here" Perlin noise layer. Smaller numbers
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-- result in more abundant plants. Range of -1 to +1,
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-- with values in the range of about 0 to 0.5 being
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-- most useful. Defaults to 0.1.
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temp_min = num, -- Coldest allowable temperature for a plant to spawn
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-- (that is, the largest Perlin value).
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temp_max = num, -- warmest allowable temperature to spawn a plant
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-- (lowest Perlin value).
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verticals_list = {table}, -- Same as with the spawn_on_surfaces function.
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check_air = bool, -- Flag to tell the mapgen code to check for air above
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-- the spawn target. Defaults to true if not
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-- explicitly set to false. Set this to false VERY
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-- SPARINGLY, as it will slow the map generator down.
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delete_above = bool, -- Flag to tell the mapgen code to delete the two
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-- nodes directly above the spawn target just before
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-- adding the plant or tree. Useful when generating
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-- in snow biomes. Defaults to false.
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delete_above_surround = bool, -- Flag to tell the mapgen code to also
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-- delete the five nodes surrounding the above space,
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-- and the five nodes above those, resulting in a two-
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-- node-deep cross-shaped empty region above/around
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-- the spawn target. Useful when adding trees to snow
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-- biomes. Defaults to false.
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spawn_replace_node = bool, -- same as with the ABM spawner.
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random_facedir = {table}, -- same as with the ABM spawner.
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}
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Regarding nodes_or_function_or_treedef, this must either be a string naming
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a node to spawn, a table with a list of nodes to choose from, a table with an
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L-Systems tree definition, or a function.
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If you specified a string, the code will attempt to determine whether that
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string specifies a valid node name. If it does, that node will be placed on
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top of the target position directly (unless one of the other mapgen options
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directs the code to do otherwise).
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If you specified a table and there is no "axiom" field, the code assumes that
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it is a list of nodes. Simply name one node per entry in the list, e.g.
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{"default:junglegrass", "default:dry_shrub"} and so on, for as many nodes as
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you want to list. A random node from the list will be chosen each time the
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code goes to place a node.
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If you specified a table, and there *is* an "axiom" field, the code assumes
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that this table contains an L-Systems tree definition, which will be passed
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directly to the engine's spawn_tree() function along with the position on
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which to spawn the tree.
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You can also supply a function to be directly executed, which is given the
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current node position (the usual "pos" table format) as its sole argument. It
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will be called in the form:
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somefunction(pos)
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=====
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biome_lib.update_plant(options)
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This third function is used to turn the spawned nodes above into something
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else over time. This function has no return value, and accepts a biome
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definition table as the only parameter. These are defined like so:
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options = {
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label = string, -- set this to identify the ABM for Minetest's
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-- profiler. If not set, biome_lib will set it to
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-- "biome_lib.update_plant(): " appended with the node
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-- in grow_plant (or the first item if it's a table)
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grow_plant = "string" or {table}, -- Name(s) of the node(s) to be grown
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-- into something else. This value is passed to the
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-- ABM as the "nodenames" parameter, so the plants
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-- themselves are the ABM trigger, rather than
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-- the ground they spawned on. A plant will only grow
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-- if the node above it is air. If you use a table,
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-- note that all nodes referenced therein will be
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-- grown into the same final object.
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grow_delay = num, -- Passed as the ABM "interval" parameter, as with
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-- spawning.
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grow_chance = num, -- Passed as the ABM "chance" parameter.
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grow_result = "string", -- Name of the node into which the grow_plant
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-- node(s) should transform when the ABM executes.
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---- Everything from here down is optional.
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dry_early_node = "string", -- This value is ignored except for jungle
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-- grass (a corner case needed by that mod), where it
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-- indicates which node the grass must be on in order
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-- for it to turn from the short size to
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-- "default:dry_shrub" instead of the medium size.
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grow_nodes = {table}, -- One of these nodes must be under the plant in
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-- order for it to grow at all. Normally this should
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-- be the same as the list of surfaces passed to the
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-- spawning ABM as the "nodenames" parameter. This is
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-- so that the plant can be manually placed on
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-- something like a flower pot or something without it
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-- necessarily growing and perhaps dieing. Defaults
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-- to "default:dirt_with_grass".
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facedir = num, -- Same as with spawning a plant.
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need_wall = bool, -- Set this to true if you the plant needs to grow
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-- against a wall. Defaults to false.
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verticals_list = {table}, -- same as with spawning a plant.
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choose_random_wall = bool, -- same as with spawning a plant.
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grow_vertically = bool, -- Set this to true if the plant needs to grow
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-- vertically, as in climbing poison ivy. Defaults to
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-- false.
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height_limit = num, -- Set this to limit how tall the desired node can
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-- grow. The mod will search straight down from the
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-- position being spawned at to find a ground node,
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-- set via the field below. Defaults to 5 nodes.
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ground_nodes = {table}, -- What nodes should be treated as "the ground"
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-- below a vertically-growing plant. Usually this
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-- should be the same as the grow_nodes table, but
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-- might also include, for example, water or some
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-- other surrounding material. Defaults to
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-- "default:dirt_with_grass".
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grow_function = something, -- [*] see below.
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seed_diff = num, -- [*] see below.
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}
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[*] grow_function can take one of three possible settings: it can be nil (or
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not provided), a string, or a table.
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If it is not provided or it's set to nil, all of the regular growing code is
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executed normally, the value of seed_diff, if any, is ignored, and the node to
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be placed is assumed to be specified in the grow_result variable.
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If this value is set to a simple string, this is treated as the name of the
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function to use to grow the plant. In this case, all of the usual growing
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code is executeed, but then instead of a plant being simply added to the
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world, grow_result is ignored and the named function is executed and passed a
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few parmeters in the following general form:
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somefunction(pos, perlin1, perlin2)
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These values represent the current position (the usual table), the Perlin
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noise value for that spot in the generic "plants can grow here" map for the
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seed_diff value above, the Perlin value for that same spot from the
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temperature map, and the detected neighboring wall face, if there was one (or
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nil if not). If seed_diff is not provided, it defaults to 0.
|
|
|
|
If this variable is instead set to a table, it is treated an an L-Systems tree
|
|
definition. All of the growing code is executed in the usual manner, then the
|
|
tree described by that definition is spawned at the current position instead,
|
|
and grow_result is ignored.
|
|
|
|
|
|
=====
|
|
biome_lib.find_adjacent_wall(pos, verticals, randomflag)
|
|
|
|
Of the few helper functions, this one expects a position parameter and a table
|
|
with the list of nodes that should be considered as walls. The code will
|
|
search around the given position for a neighboring wall, returning the first
|
|
one it finds as a facedir value, or nil if there are no adjacent walls.
|
|
|
|
If randomflag is set to true, the function will just return the facedir of any
|
|
random wall it finds adjacent to the target position. Defaults to false if
|
|
not specified.
|
|
|
|
=====
|
|
biome_lib.is_node_loaded(pos)
|
|
|
|
This acts as a wrapper for the minetest.get_node_or_nil(node_pos)
|
|
function and accepts a single position parameter. Returns true if the node in
|
|
question is already loaded, or false if not.
|
|
|
|
|
|
=====
|
|
biome_lib.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_ltree(pos, treemodel)
|
|
biome_lib.grow_ltree(pos, treemodel)
|
|
|
|
In the case of the growing code and the mapgen-based tree generator code,
|
|
generating a tree is done via the above two calls, which in turn immediately
|
|
call the usual spawn_tree() functions. This rerouting exists as a way for
|
|
other mods to hook into biome_lib's tree-growing functions in general,
|
|
perhaps to execute something extra whenever a tree is spawned.
|
|
|
|
biome_lib.generate_ltree(pos, treemodel) is called any time a tree is spawned
|
|
at map generation time. 'pos' is the position of the block on which the tree
|
|
is to be placed. 'treemodel' is the standard L-Systems tree definition table
|
|
expected by the spawn_tree() function. Refer to the 'trunk' field in that
|
|
table to derive the name of the tree being spawned.
|
|
|
|
biome_lib.grow_ltree(pos, treemodel) does the same sort of thing whenever a
|
|
tree is spawned within the abm-based growing code, for example when growing a
|
|
sapling into a tree.
|
|
|
|
|
|
=====
|
|
There are other, internal helper functions that are not meant for use by other
|
|
mods. Don't rely on them, as they are subject to change without notice.
|
|
|
|
======================
|
|
Fertile Ground Mapping
|
|
======================
|
|
|
|
The mod uses Perlin noise to create "biomes" of the various plants, via the
|
|
minetest.get_perlin() function. At present, there are three layers of
|
|
Perlin noise used.
|
|
|
|
The first one is for a "fertile ground" layer, which I tend to refer to as the
|
|
generic "stuff can potentially grow here" layer. Its values are hard-coded:
|
|
|
|
perlin_octaves = 3
|
|
perlin_persistence = 0.6
|
|
perlin_scale = 100
|
|
|
|
For more information on how Perlin noise is generated, you will need to search
|
|
the web, as these default values were from that which is used by minetest_game
|
|
to spawn jungle grass at mapgen time, and I'm still learning how Perlin noise
|
|
works. ;-)
|
|
|
|
|
|
===================
|
|
Temperature Mapping
|
|
===================
|
|
|
|
The second Perlin layer is a temperature map, with values taken from
|
|
SPlizard's Snow Biomes mod so that the two will be compatible, since that mod
|
|
appears to be the standard now. Those values are:
|
|
|
|
temperature_seeddiff = 112
|
|
temperature_octaves = 3
|
|
temperature_persistence = 0.5
|
|
temperature_scale = 150
|
|
|
|
The way Perlin values are used by this mod, in keeping with the snow mod's
|
|
apparent methods, larger values returned by the Perlin function represent
|
|
*colder* temperatures. In this mod, the following table gives a rough
|
|
approximation of how temperature maps to these values, normalized to
|
|
0.53 = 0 °C and +1.0 = -25 °C.
|
|
|
|
Perlin Approx. Temperature
|
|
-1.0 81 °C ( 178 °F)
|
|
-0.75 68 °C ( 155 °F)
|
|
-0.56 58 °C ( 136 °F)
|
|
-0.5 55 °C ( 131 °F)
|
|
-0.25 41 °C ( 107 °F)
|
|
-0.18 38 °C ( 100 °F)
|
|
0 28 °C ( 83 °F)
|
|
0.13 21 °C ( 70 °F)
|
|
0.25 15 °C ( 59 °F)
|
|
0.5 2 °C ( 35 °F)
|
|
0.53 0 °C ( 32 °F)
|
|
0.75 -12 °C ( 11 °F)
|
|
0.86 -18 °C ( 0 °F)
|
|
1.0 -25 °C (- 13 °F)
|
|
|
|
Included in this table are even 0.25 steps in Perlin values along with some
|
|
common temperatures on both the Centigrade and Fahrenheit scales. Note that
|
|
unless you're trying to model the Moon or perhaps Mercury in your mods/maps,
|
|
you probably won't need to bother with Perlin values of less than -0.56 or so.
|
|
|
|
|
|
================
|
|
Humidity Mapping
|
|
================
|
|
|
|
Last but not least is a moisture/humidity map. Like the temperature map
|
|
above, Perlin values can be tested to determine the approximate humidity of
|
|
the *air* in the area. This humidity map is basically the perlin layer used
|
|
for deserts.
|
|
|
|
A value of +1.0 is very moist (basically a thick fog, if it could be seen), a
|
|
value of roughly +0.25 represents the edge of a desert as usually seen in the
|
|
game, and a value of -1.0 is as dry as a bone.
|
|
|
|
This does not check for nearby water, just general air humidity, and that
|
|
being the case, nearby ground does not affect the reported humidity of a
|
|
region (because this isn't yet possible to calculate yet). Use the near_nodes
|
|
and avoid_nodes parameters and their related options to check for water and
|
|
such.
|
|
|
|
The Perlin values use for this layer are:
|
|
|
|
humidity_seeddiff = 9130
|
|
humidity_octaves = 3
|
|
humidity_persistence = 0.5
|
|
humidity_scale = 250
|
|
|
|
And this particular one is mapped slightly differently from the others:
|
|
|
|
noise3 = perlin3:get2d({x=p_top.x+150, y=p_top.z+50})
|
|
|
|
(Note the +150 and +50 offsets)
|
|
|
|
|
|
==================
|
|
Default game nodes
|
|
==================
|
|
|
|
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.
|
|
|
|
See settingtypes.txt for a list. Any item listed there can be changed either
|
|
by adding it to your minetest.conf, or by using the "all settings" menu in
|
|
Minetest, whatever's appropriate for your particular setup.
|
|
|
|
==================
|
|
Engine Decorations
|
|
==================
|
|
|
|
If a call to biome_lib.register_on_generate() contains items and biome
|
|
definition settings that are suitable, biome_lib will pass that call on to the
|
|
engine instead, to use its built-in decorations feature, since it'll be much
|
|
faster than Lua.
|
|
|
|
For this to work, first the item to be added must either be a node, or a
|
|
table with a list of nodes that biome_lib would normally pick from randomly.
|
|
That is to say, you cannot specify an L-tree or a function here, as the engine
|
|
does not support that sort of thing (biome_lib will just switch to its normal
|
|
handling if you do).
|
|
|
|
Second, these biome definition items must not be present:
|
|
|
|
* below_nodes
|
|
* avoid_nodes
|
|
* avoid_radius
|
|
* neighbors
|
|
* ncount
|
|
* depth
|
|
* near_nodes_size
|
|
* near_nodes_vertical
|
|
* temp_min
|
|
* temp_max
|
|
* verticals_list
|
|
* delete_above
|
|
* delete_above_surround
|
|
|
|
The plantlife_limit definition item is ignored when checking if a particular
|
|
call can be routed to the engine.
|
|
|
|
The call given to the engine will use the remaining biome definition items in
|
|
the following manner:
|
|
|
|
deco_type = "simple",
|
|
flags = "all_floors"
|
|
decoration = node or table with node list
|
|
place_on = surface
|
|
y_min = min_elevation
|
|
y_max = max_elevation
|
|
spawn_by = near_nodes
|
|
num_spawn_by = near_nodes_count
|
|
param2 = \_ set to the range specified by the biome definition's
|
|
param2_max = / random_facedir table, if present, otherwise omitted
|
|
noise_params = {
|
|
octaves = biome_lib.fertile_perlin_octaves,
|
|
persist = biome_lib.fertile_perlin_persistence * (250/biome_lib.fertile_perlin_scale),
|
|
scale = ((100-biome.rarity)/100) * (math.min(biome.max_count, 6400)/6400),
|
|
seed = biome.seed_diff,
|
|
offset = 0,
|
|
spread = {x = 100, y = 100, z = 100},
|
|
lacunarity = 2,
|
|
flags = "absvalue"
|
|
}
|
|
|
|
If the biome definition's check_air setting is false, "force_placement" is
|
|
added to the decoration's flags setting.
|
|
|
|
If the biome def's spawn_replace_node is set to true, the decoration's
|
|
place_offset_y is set to -1 (otherwise it is omitted).
|