Definition tables¶

{
    hp_max = 10,
    -- Defines the maximum and default HP of the object.
    -- For Lua entities, the maximum is not enforced.
    -- For players, this defaults to `core.PLAYER_MAX_HP_DEFAULT` (20).
    -- For Lua entities, the default is 10.

    breath_max = 0,
    -- For players only. Defines the maximum amount of "breath" for the player.
    -- Defaults to `core.PLAYER_MAX_BREATH_DEFAULT` (10).

    zoom_fov = 0.0,
    -- For players only. Zoom FOV in degrees.
    -- Note that zoom loads and/or generates world beyond the server's
    -- maximum send and generate distances, so acts like a telescope.
    -- Smaller zoom_fov values increase the distance loaded/generated.
    -- Defaults to 15 in creative mode, 0 in survival mode.
    -- zoom_fov = 0 disables zooming for the player.

    eye_height = 1.625,
    -- For players only. Camera height above feet position in nodes.

    physical = false,
    -- Collide with `walkable` nodes.

    collide_with_objects = true,
    -- Collide with other objects if physical = true

    collisionbox = { -0.5, -0.5, -0.5, 0.5, 0.5, 0.5 },  -- default
    selectionbox = { -0.5, -0.5, -0.5, 0.5, 0.5, 0.5, rotate = false },
    -- { xmin, ymin, zmin, xmax, ymax, zmax } in nodes from object position.
    -- Collision boxes cannot rotate, setting `rotate = true` on it has no effect.
    -- If not set, the selection box copies the collision box, and will also not rotate.
    -- If `rotate = false`, the selection box will not rotate with the object itself, remaining fixed to the axes.
    -- If `rotate = true`, it will match the object's rotation and any attachment rotations.
    -- Raycasts use the selection box and object's rotation, but do *not* obey attachment rotations.
    -- For server-side raycasts to work correctly,
    -- the selection box should extend at most 5 units in each direction.


    pointable = true,
    -- Can be `true` if it is pointable, `false` if it can be pointed through,
    -- or `"blocking"` if it is pointable but not selectable.
    -- Clients older than 5.9.0 interpret `pointable = "blocking"` as `pointable = true`.
    -- Can be overridden by the `pointabilities` of the held item.

    visual = "cube" / "sprite" / "upright_sprite" / "mesh" / "wielditem" / "item",
    -- "cube" is a node-sized cube.
    -- "sprite" is a flat texture always facing the player.
    -- "upright_sprite" is a vertical flat texture.
    -- "mesh" uses the defined mesh model.
    -- "wielditem" is used for dropped items.
    --   (see builtin/game/item_entity.lua).
    --   For this use 'wield_item = itemname'.
    --   Setting 'textures = {itemname}' has the same effect, but is deprecated.
    --   If the item has a 'wield_image' the object will be an extrusion of
    --   that, otherwise:
    --   If 'itemname' is a cubic node or nodebox the object will appear
    --   identical to 'itemname'.
    --   If 'itemname' is a plantlike node the object will be an extrusion
    --   of its texture.
    --   Otherwise for non-node items, the object will be an extrusion of
    --   'inventory_image'.
    --   If 'itemname' contains a ColorString or palette index (e.g. from
    --   `core.itemstring_with_palette()`), the entity will inherit the color.
    --   Wielditems are scaled a bit. If you want a wielditem to appear
    --   to be as large as a node, use `0.667` in `visual_size`
    -- "item" is similar to "wielditem" but ignores the 'wield_image' parameter.

    visual_size = {x = 1, y = 1, z = 1},
    -- Multipliers for the visual size. If `z` is not specified, `x` will be used
    -- to scale the entity along both horizontal axes.

    mesh = "model.obj",
    -- File name of mesh when using "mesh" visual

    textures = {},
    -- Number of required textures depends on visual.
    -- "cube" uses 6 textures just like a node, but all 6 must be defined.
    -- "sprite" uses 1 texture.
    -- "upright_sprite" uses 2 textures: {front, back}.
    -- "mesh" requires one texture for each mesh buffer/material (in order)
    -- Deprecated usage of "wielditem" expects 'textures = {itemname}' (see 'visual' above).

    colors = {},
    -- Number of required colors depends on visual

    use_texture_alpha = false,
    -- Use texture's alpha channel.
    -- Excludes "upright_sprite" and "wielditem".
    -- Note: currently causes visual issues when viewed through other
    -- semi-transparent materials such as water.

    spritediv = {x = 1, y = 1},
    -- Used with spritesheet textures for animation and/or frame selection
    -- according to position relative to player.
    -- Defines the number of columns and rows in the spritesheet:
    -- {columns, rows}.

    initial_sprite_basepos = {x = 0, y = 0},
    -- Used with spritesheet textures.
    -- Defines the {column, row} position of the initially used frame in the
    -- spritesheet.

    is_visible = true,
    -- If false, object is invisible and can't be pointed.

    makes_footstep_sound = false,
    -- If true, is able to make footstep sounds of nodes
    -- (see node sound definition for details).

    automatic_rotate = 0,
    -- Set constant rotation in radians per second, positive or negative.
    -- Object rotates along the local Y-axis, and works with set_rotation.
    -- Set to 0 to disable constant rotation.

    stepheight = 0,
    -- If positive number, object will climb upwards when it moves
    -- horizontally against a `walkable` node, if the height difference
    -- is within `stepheight`.

    automatic_face_movement_dir = 0.0,
    -- Automatically set yaw to movement direction, offset in degrees.
    -- 'false' to disable.

    automatic_face_movement_max_rotation_per_sec = -1,
    -- Limit automatic rotation to this value in degrees per second.
    -- No limit if value <= 0.

    backface_culling = true,
    -- Set to false to disable backface_culling for model

    glow = 0,
    -- Add this much extra lighting when calculating texture color.
    -- Value < 0 disables light's effect on texture color.
    -- For faking self-lighting, UI style entities, or programmatic coloring
    -- in mods.

    nametag = "",
    -- The name to display on the head of the object. By default empty.
    -- If the object is a player, a nil or empty nametag is replaced by the player's name.
    -- For all other objects, a nil or empty string removes the nametag.
    -- To hide a nametag, set its color alpha to zero. That will disable it entirely.

    nametag_color = <ColorSpec>,
    -- Sets text color of nametag

    nametag_bgcolor = <ColorSpec>,
    -- Sets background color of nametag
    -- `false` will cause the background to be set automatically based on user settings.
    -- Default: false

    infotext = "",
    -- Same as infotext for nodes. Empty by default

    static_save = true,
    -- If false, never save this object statically. It will simply be
    -- deleted when the block gets unloaded.
    -- The get_staticdata() callback is never called then.
    -- Defaults to 'true'.

    damage_texture_modifier = "^[brighten",
    -- Texture modifier to be applied for a short duration when object is hit

    shaded = true,
    -- Setting this to 'false' disables diffuse lighting of entity

    show_on_minimap = false,
    -- Defaults to true for players, false for other entities.
    -- If set to true the entity will show as a marker on the minimap.
}

{
    initial_properties = {
        visual = "mesh",
        mesh = "boats_boat.obj",
        ...,
    },
    -- A table of object properties, see the `Object properties` section.
    -- The properties in this table are applied to the object
    -- once when it is spawned.

    -- Refer to the "Registered entities" section for explanations
    on_activate = function(self, staticdata, dtime_s) end,
    on_deactivate = function(self, removal) end,
    on_step = function(self, dtime, moveresult) end,
    on_punch = function(self, puncher, time_from_last_punch, tool_capabilities, dir, damage) end,
    on_death = function(self, killer) end,
    on_rightclick = function(self, clicker) end,
    on_attach_child = function(self, child) end,
    on_detach_child = function(self, child) end,
    on_detach = function(self, parent) end,
    get_staticdata = function(self) end,

    _custom_field = whatever,
    -- You can define arbitrary member variables here (see Item definition
    -- for more info) by using a '_' prefix
}

{
    label = "Lava cooling",
    -- Descriptive label for profiling purposes (optional).
    -- Definitions with identical labels will be listed as one.

    nodenames = {"default:lava_source"},
    -- Apply `action` function to these nodes.
    -- `group:groupname` can also be used here.

    neighbors = {"default:water_source", "default:water_flowing"},
    -- Only apply `action` to nodes that have one of, or any
    -- combination of, these neighbors.
    -- If left out or empty, any neighbor will do.
    -- `group:groupname` can also be used here.

    without_neighbors = {"default:lava_source", "default:lava_flowing"},
    -- Only apply `action` to nodes that have no one of these neighbors.
    -- If left out or empty, it has no effect.
    -- `group:groupname` can also be used here.

    interval = 10.0,
    -- Operation interval in seconds

    chance = 50,
    -- Probability of triggering `action` per-node per-interval is 1.0 / chance (integers only)

    min_y = -32768,
    max_y = 32767,
    -- min and max height levels where ABM will be processed (inclusive)
    -- can be used to reduce CPU usage

    catch_up = true,
    -- If true, catch-up behavior is enabled: The `chance` value is
    -- temporarily reduced when returning to an area to simulate time lost
    -- by the area being unattended. Note that the `chance` value can often
    -- be reduced to 1.

    action = function(pos, node, active_object_count, active_object_count_wider),
    -- Function triggered for each qualifying node.
    -- `active_object_count` is number of active objects in the node's
    -- mapblock.
    -- `active_object_count_wider` is number of active objects in the node's
    -- mapblock plus all 26 neighboring mapblocks. If any neighboring
    -- mapblocks are unloaded an estimate is calculated for them based on
    -- loaded mapblocks.
}

{
    label = "Upgrade legacy doors",
    -- Descriptive label for profiling purposes (optional).
    -- Definitions with identical labels will be listed as one.

    name = "modname:replace_legacy_door",
    -- Identifier of the LBM, should follow the modname:<whatever> convention

    nodenames = {"default:lava_source"},
    -- List of node names to trigger the LBM on.
    -- Names of non-registered nodes and groups (as group:groupname)
    -- will work as well.

    run_at_every_load = false,
    -- Whether to run the LBM's action every time a block gets activated,
    -- and not only the first time the block gets activated after the LBM
    -- was introduced.

    action = function(pos, node, dtime_s) end,
    -- Function triggered for each qualifying node.
    -- `dtime_s` is the in-game time (in seconds) elapsed since the block
    -- was last active.

    bulk_action = function(pos_list, dtime_s) end,
    -- Function triggered with a list of all applicable node positions at once.
    -- This can be provided as an alternative to `action` (not both).
    -- Available since `core.features.bulk_lbms` (5.10.0)
    -- `dtime_s`: as above
}

{
    type = "vertical_frames",

    aspect_w = 16,
    -- Width of a frame in pixels

    aspect_h = 16,
    -- Height of a frame in pixels

    length = 3.0,
    -- Full loop length
}

{
    type = "sheet_2d",

    frames_w = 5,
    -- Width in number of frames

    frames_h = 3,
    -- Height in number of frames

    frame_length = 0.5,
    -- Length of a single frame
}

{
    description = "",
    -- Can contain new lines. "\n" has to be used as new line character.
    -- See also: `get_description` in [`ItemStack`]

    short_description = "",
    -- Must not contain new lines.
    -- Defaults to nil.
    -- Use an [`ItemStack`] to get the short description, e.g.:
    --   ItemStack(itemname):get_short_description()

    groups = {},
    -- key = name, value = rating; rating = <number>.
    -- If rating not applicable, use 1.
    -- e.g. {wool = 1, fluffy = 3}
    --      {soil = 2, outerspace = 1, crumbly = 1}
    --      {bendy = 2, snappy = 1},
    --      {hard = 1, metal = 1, spikes = 1}

    inventory_image = "",
    -- Texture shown in the inventory GUI
    -- Defaults to a 3D rendering of the node if left empty.

    inventory_overlay = "",
    -- An overlay texture which is not affected by colorization

    wield_image = "",
    -- Texture shown when item is held in hand
    -- Defaults to a 3D rendering of the node if left empty.

    wield_overlay = "",
    -- Like inventory_overlay but only used in the same situation as wield_image

    wield_scale = {x = 1, y = 1, z = 1},
    -- Scale for the item when held in hand

    palette = "",
    -- An image file containing the palette of a node.
    -- You can set the currently used color as the "palette_index" field of
    -- the item stack metadata.
    -- The palette is always stretched to fit indices between 0 and 255, to
    -- ensure compatibility with "colorfacedir" (and similar) nodes.

    color = "#ffffffff",
    -- Color the item is colorized with. The palette overrides this.

    stack_max = 99,
    -- Maximum amount of items that can be in a single stack.
    -- The default can be changed by the setting `default_stack_max`

    range = 4.0,
    -- Range of node and object pointing that is possible with this item held
    -- Can be overridden with itemstack meta.

    liquids_pointable = false,
    -- If true, item can point to all liquid nodes (`liquidtype ~= "none"`),
    -- even those for which `pointable = false`

    pointabilities = {
        nodes = {
            ["default:stone"] = "blocking",
            ["group:leaves"] = false,
        },
        objects = {
            ["modname:entityname"] = true,
            ["group:ghosty"] = true, -- (an armor group)
        },
    },
    -- Contains lists to override the `pointable` property of nodes and objects.
    -- The index can be a node/entity name or a group with the prefix `"group:"`.
    -- (For objects `armor_groups` are used and for players the entity name is irrelevant.)
    -- If multiple fields fit, the following priority order is applied:
    -- 1. value of matching node/entity name
    -- 2. `true` for any group
    -- 3. `false` for any group
    -- 4. `"blocking"` for any group
    -- 5. `liquids_pointable` if it is a liquid node
    -- 6. `pointable` property of the node or object

    light_source = 0,
    -- When used for nodes: Defines amount of light emitted by node.
    -- Otherwise: Defines texture glow when viewed as a dropped item
    -- To set the maximum (14), use the value 'core.LIGHT_MAX'.
    -- A value outside the range 0 to core.LIGHT_MAX causes undefined
    -- behavior.

    -- See "Tool Capabilities" section for an example including explanation
    tool_capabilities = {
        full_punch_interval = 1.0,
        max_drop_level = 0,
        groupcaps = {
            -- For example:
            choppy = {times = {2.50, 1.40, 1.00}, uses = 20, maxlevel = 2},
        },
        damage_groups = {groupname = damage},
        -- Damage values must be between -32768 and 32767 (2^15)

        punch_attack_uses = nil,
        -- Amount of uses this tool has for attacking players and entities
        -- by punching them (0 = infinite uses).
        -- For compatibility, this is automatically set from the first
        -- suitable groupcap using the formula "uses * 3^(maxlevel - 1)".
        -- It is recommend to set this explicitly instead of relying on the
        -- fallback behavior.
    },

    -- Set wear bar color of the tool by setting color stops and blend mode
    -- See "Wear Bar Color" section for further explanation including an example
    wear_color = {
        -- interpolation mode: 'constant' or 'linear'
        -- (nil defaults to 'constant')
        blend = "linear",
        color_stops = {
            [0.0] = "#ff0000",
            [0.5] = "#ffff00",
            [1.0] = "#00ff00",
        }
    },

    node_placement_prediction = nil,
    -- If nil and item is node, prediction is made automatically.
    -- If nil and item is not a node, no prediction is made.
    -- If "" and item is anything, no prediction is made.
    -- Otherwise should be name of node which the client immediately places
    -- on ground when the player places the item. Server will always update
    -- with actual result shortly.

    node_dig_prediction = "air",
    -- if "", no prediction is made.
    -- if "air", node is removed.
    -- Otherwise should be name of node which the client immediately places
    -- upon digging. Server will always update with actual result shortly.

    touch_interaction = <TouchInteractionMode> OR {
        pointed_nothing = <TouchInteractionMode>,
        pointed_node    = <TouchInteractionMode>,
        pointed_object  = <TouchInteractionMode>,
    },
      -- Only affects touchscreen clients.
      -- Defines the meaning of short and long taps with the item in hand.
      -- If specified as a table, the field to be used is selected according to
      -- the current `pointed_thing`.
      -- There are three possible TouchInteractionMode values:
      -- * "long_dig_short_place" (long tap  = dig, short tap = place)
      -- * "short_dig_long_place" (short tap = dig, long tap  = place)
      -- * "user":
      --   * For `pointed_object`: Equivalent to "short_dig_long_place" if the
      --     client-side setting "touch_punch_gesture" is "short_tap" (the
      --     default value) and the item is able to punch (i.e. has no on_use
      --     callback defined).
      --     Equivalent to "long_dig_short_place" otherwise.
      --   * For `pointed_node` and `pointed_nothing`:
      --     Equivalent to "long_dig_short_place".
      --   * The behavior of "user" may change in the future.
      -- The default value is "user".

    sound = {
        -- Definition of item sounds to be played at various events.
        -- All fields in this table are optional.

        breaks = <SimpleSoundSpec>,
        -- When tool breaks due to wear. Ignored for non-tools

        eat = <SimpleSoundSpec>,
        -- When item is eaten with `core.do_item_eat`

        punch_use = <SimpleSoundSpec>,
        -- When item is used with the 'punch/mine' key pointing at a node or entity

        punch_use_air = <SimpleSoundSpec>,
        -- When item is used with the 'punch/mine' key pointing at nothing (air)
    },

    on_place = function(itemstack, placer, pointed_thing),
    -- When the 'place' key was pressed with the item in hand
    -- and a node was pointed at.
    -- Shall place item and return the leftover itemstack
    -- or nil to not modify the inventory.
    -- The placer may be any ObjectRef or nil.
    -- default: core.item_place

    on_secondary_use = function(itemstack, user, pointed_thing),
    -- Same as on_place but called when not pointing at a node.
    -- Function must return either nil if inventory shall not be modified,
    -- or an itemstack to replace the original itemstack.
    -- The user may be any ObjectRef or nil.
    -- default: nil

    on_drop = function(itemstack, dropper, pos),
    -- Shall drop item and return the leftover itemstack.
    -- The dropper may be any ObjectRef or nil.
    -- default: core.item_drop

    on_pickup = function(itemstack, picker, pointed_thing, time_from_last_punch, ...),
    -- Called when a dropped item is punched by a player.
    -- Shall pick-up the item and return the leftover itemstack or nil to not
    -- modify the dropped item.
    -- Parameters:
    -- * `itemstack`: The `ItemStack` to be picked up.
    -- * `picker`: Any `ObjectRef` or `nil`.
    -- * `pointed_thing` (optional): The dropped item (a `"__builtin:item"`
    --   luaentity) as `type="object"` `pointed_thing`.
    -- * `time_from_last_punch, ...` (optional): Other parameters from
    --   `luaentity:on_punch`.
    -- default: `core.item_pickup`

    on_use = function(itemstack, user, pointed_thing),
    -- default: nil
    -- When user pressed the 'punch/mine' key with the item in hand.
    -- Function must return either nil if inventory shall not be modified,
    -- or an itemstack to replace the original itemstack.
    -- e.g. itemstack:take_item(); return itemstack
    -- Otherwise, the function is free to do what it wants.
    -- The user may be any ObjectRef or nil.
    -- The default functions handle regular use cases.

    after_use = function(itemstack, user, node, digparams),
    -- default: nil
    -- If defined, should return an itemstack and will be called instead of
    -- wearing out the item (if tool). If returns nil, does nothing.
    -- If after_use doesn't exist, it is the same as:
    --   function(itemstack, user, node, digparams)
    --     itemstack:add_wear(digparams.wear)
    --     return itemstack
    --   end
    -- The user may be any ObjectRef or nil.

    _custom_field = whatever,
    -- Add your own custom fields. By convention, all custom field names
    -- should start with `_` to avoid naming collisions with future engine
    -- usage.
}

{
    -- <all fields allowed in item definitions>

    drawtype = "normal",  -- See "Node drawtypes"

    visual_scale = 1.0,
    -- Supported for drawtypes "plantlike", "signlike", "torchlike",
    -- "firelike", "mesh", "nodebox", "allfaces".
    -- For plantlike and firelike, the image will start at the bottom of the
    -- node. For torchlike, the image will start at the surface to which the
    -- node "attaches". For the other drawtypes the image will be centered
    -- on the node.

    tiles = {tile definition 1, def2, def3, def4, def5, def6},
    -- Textures of node; +Y, -Y, +X, -X, +Z, -Z
    -- List can be shortened to needed length.

    overlay_tiles = {tile definition 1, def2, def3, def4, def5, def6},
    -- Same as `tiles`, but these textures are drawn on top of the base
    -- tiles. You can use this to colorize only specific parts of your
    -- texture. If the texture name is an empty string, that overlay is not
    -- drawn. Since such tiles are drawn twice, it is not recommended to use
    -- overlays on very common nodes.

    special_tiles = {tile definition 1, Tile definition 2},
    -- Special textures of node; used rarely.
    -- List can be shortened to needed length.

    color = ColorSpec,
    -- The node's original color will be multiplied with this color.
    -- If the node has a palette, then this setting only has an effect in
    -- the inventory and on the wield item.

    use_texture_alpha = ...,
    -- Specifies how the texture's alpha channel will be used for rendering.
    -- Possible values:
    -- * "opaque":
    --   Node is rendered opaque regardless of alpha channel.
    -- * "clip":
    --   A given pixel is either fully see-through or opaque
    --   depending on the alpha channel being below/above 50% in value.
    --   Use this for nodes with fully transparent and fully opaque areas.
    -- * "blend":
    --   The alpha channel specifies how transparent a given pixel
    --   of the rendered node is. This comes at a performance cost.
    --   Only use this when correct rendering
    --   among semitransparent nodes is necessary.
    -- The default is "opaque" for drawtypes normal, liquid and flowingliquid,
    -- mesh and nodebox or "clip" otherwise.
    -- If set to a boolean value (deprecated): true either sets it to blend
    -- or clip, false sets it to clip or opaque mode depending on the drawtype.

    palette = "",
    -- The node's `param2` is used to select a pixel from the image.
    -- Pixels are arranged from left to right and from top to bottom.
    -- The node's color will be multiplied with the selected pixel's color.
    -- Tiles can override this behavior.
    -- Only when `paramtype2` supports palettes.

    post_effect_color = "#00000000",
    -- Screen tint if a player is inside this node, see `ColorSpec`.
    -- Color is alpha-blended over the screen.

    post_effect_color_shaded = false,
    -- Determines whether `post_effect_color` is affected by lighting.

    paramtype = "none",  -- See "Nodes"

    paramtype2 = "none",  -- See "Nodes"

    place_param2 = 0,
    -- Value for param2 that is set when player places node

    wallmounted_rotate_vertical = false,
    -- If true, place_param2 is nil, and this is a wallmounted node,
    -- this node might use the special 90° rotation when placed
    -- on the floor or ceiling, depending on the direction.
    -- See the explanation about wallmounted for details.
    -- Otherwise, the rotation is always the same on vertical placement.

    is_ground_content = true,
    -- If false, the cave generator and dungeon generator will not carve
    -- through this node.
    -- Specifically, this stops mod-added nodes being removed by caves and
    -- dungeons when those generate in a neighbor mapchunk and extend out
    -- beyond the edge of that mapchunk.

    sunlight_propagates = false,
    -- If true, sunlight will go infinitely through this node

    walkable = true,  -- If true, objects collide with node

    pointable = true,
    -- Can be `true` if it is pointable, `false` if it can be pointed through,
    -- or `"blocking"` if it is pointable but not selectable.
    -- Clients older than 5.9.0 interpret `pointable = "blocking"` as `pointable = true`.
    -- Can be overridden by the `pointabilities` of the held item.
    -- A client may be able to point non-pointable nodes, since it isn't checked server-side.

    diggable = true,  -- If false, can never be dug

    climbable = false,  -- If true, can be climbed on like a ladder

    move_resistance = 0,
    -- Slows down movement of players through this node (max. 7).
    -- If this is nil, it will be equal to liquid_viscosity.
    -- Note: If liquid movement physics apply to the node
    -- (see `liquid_move_physics`), the movement speed will also be
    -- affected by the `movement_liquid_*` settings.

    buildable_to = false,  -- If true, placed nodes can replace this node

    floodable = false,
    -- If true, liquids flow into and replace this node.
    -- Warning: making a liquid node 'floodable' will cause problems.

    liquidtype = "none",  -- specifies liquid flowing physics
    -- * "none":    no liquid flowing physics
    -- * "source":  spawns flowing liquid nodes at all 4 sides and below;
    --              recommended drawtype: "liquid".
    -- * "flowing": spawned from source, spawns more flowing liquid nodes
    --              around it until `liquid_range` is reached;
    --              will drain out without a source;
    --              recommended drawtype: "flowingliquid".
    -- If it's "source" or "flowing", then the
    -- `liquid_alternative_*` fields _must_ be specified

    liquid_alternative_flowing = "",
    liquid_alternative_source = "",
    -- These fields may contain node names that represent the
    -- flowing version (`liquid_alternative_flowing`) and
    -- source version (`liquid_alternative_source`) of a liquid.
    --
    -- Specifically, these fields are required if `liquidtype ~= "none"` or
    -- `drawtype == "flowingliquid"`.
    --
    -- Liquids consist of up to two nodes: source and flowing.
    --
    -- There are two ways to define a liquid:
    -- 1) Source node and flowing node. This requires both fields to be
    --    specified for both nodes.
    -- 2) Standalone source node (cannot flow). `liquid_alternative_source`
    --    must be specified and `liquid_range` must be set to 0.
    --
    -- Example:
    --     liquid_alternative_flowing = "example:water_flowing",
    --     liquid_alternative_source = "example:water_source",

    liquid_viscosity = 0,
    -- Controls speed at which the liquid spreads/flows (max. 7).
    -- 0 is fastest, 7 is slowest.
    -- By default, this also slows down movement of players inside the node
    -- (can be overridden using `move_resistance`)

    liquid_renewable = true,
    -- If true, a new liquid source can be created by placing two or more
    -- sources nearby

    liquid_move_physics = nil, -- specifies movement physics if inside node
    -- * false: No liquid movement physics apply.
    -- * true: Enables liquid movement physics. Enables things like
    --   ability to "swim" up/down, sinking slowly if not moving,
    --   smoother speed change when falling into, etc. The `movement_liquid_*`
    --   settings apply.
    -- * nil: Will be treated as true if `liquidtype ~= "none"`
    --   and as false otherwise.

    air_equivalent = nil,
    -- unclear meaning, the engine sets this to true for 'air' and 'ignore'
    -- deprecated.

    leveled = 0,
    -- Only valid for "nodebox" drawtype with 'type = "leveled"'.
    -- Allows defining the nodebox height without using param2.
    -- The nodebox height is 'leveled' / 64 nodes.
    -- The maximum value of 'leveled' is `leveled_max`.

    leveled_max = 127,
    -- Maximum value for `leveled` (0-127), enforced in
    -- `core.set_node_level` and `core.add_node_level`.
    -- Values above 124 might causes collision detection issues.

    liquid_range = 8,
    -- Maximum distance that flowing liquid nodes can spread around
    -- source on flat land;
    -- maximum = 8; set to 0 to disable liquid flow

    drowning = 0,
    -- Player will take this amount of damage if no bubbles are left

    damage_per_second = 0,
    -- If player is inside node, this damage is caused

    node_box = {type = "regular"},  -- See "Node boxes"

    connects_to = {},
    -- Used for nodebox nodes with the type == "connected".
    -- Specifies to what neighboring nodes connections will be drawn.
    -- e.g. `{"group:fence", "default:wood"}` or `"default:stone"`

    connect_sides = {},
    -- Tells connected nodebox nodes to connect only to these sides of this
    -- node. possible: "top", "bottom", "front", "left", "back", "right"

    mesh = "",
    -- File name of mesh when using "mesh" drawtype

    selection_box = {
        -- see [Node boxes] for possibilities
    },
    -- Custom selection box definition. Multiple boxes can be defined.
    -- If "nodebox" drawtype is used and selection_box is nil, then node_box
    -- definition is used for the selection box.

    collision_box = {
        -- see [Node boxes] for possibilities
    },
    -- Custom collision box definition. Multiple boxes can be defined.
    -- If "nodebox" drawtype is used and collision_box is nil, then node_box
    -- definition is used for the collision box.

    -- Support maps made in and before January 2012
    legacy_facedir_simple = false,
    legacy_wallmounted = false,

    waving = 0,
    -- Valid for drawtypes:
    -- mesh, nodebox, plantlike, allfaces_optional, liquid, flowingliquid.
    -- 1 - wave node like plants (node top moves side-to-side, bottom is fixed)
    -- 2 - wave node like leaves (whole node moves side-to-side)
    -- 3 - wave node like liquids (whole node moves up and down)
    -- Not all models will properly wave.
    -- plantlike drawtype can only wave like plants.
    -- allfaces_optional drawtype can only wave like leaves.
    -- liquid, flowingliquid drawtypes can only wave like liquids.

    sounds = {
        -- Definition of node sounds to be played at various events.
        -- All fields in this table are optional.

        footstep = <SimpleSoundSpec>,
        -- If walkable, played when object walks on it. If node is
        -- climbable or a liquid, played when object moves through it.
        -- Sound is played at the base of the object's collision-box.
        -- Gain is multiplied by `0.6`.
        -- For local player, it's played position-less, with normal gain.

        dig = <SimpleSoundSpec> or "__group",
        -- While digging node.
        -- If `"__group"`, then the sound will be
        -- `{name = "default_dig_<groupname>", gain = 0.5}` , where `<groupname>` is the
        -- name of the item's digging group with the fastest digging time.
        -- In case of a tie, one of the sounds will be played (but we
        -- cannot predict which one)
        -- Default value: `"__group"`

        dug = <SimpleSoundSpec>,
        -- Node was dug

        place = <SimpleSoundSpec>,
        -- Node was placed. Also played after falling

        place_failed = <SimpleSoundSpec>,
        -- When node placement failed.
        -- Note: This happens if the _built-in_ node placement failed.
        -- This sound will still be played if the node is placed in the
        -- `on_place` callback manually.

        fall = <SimpleSoundSpec>,
        -- When node starts to fall or is detached
    },

    drop = "",
    -- Name of dropped item when dug.
    -- Default dropped item is the node itself.

    -- Using a table allows multiple items, drop chances and item filtering:
    drop = {
        max_items = 1,
        -- Maximum number of item lists to drop.
        -- The entries in 'items' are processed in order. For each:
        -- Item filtering is applied, chance of drop is applied, if both are
        -- successful the entire item list is dropped.
        -- Entry processing continues until the number of dropped item lists
        -- equals 'max_items'.
        -- Therefore, entries should progress from low to high drop chance.
        items = {
            -- Examples:
            {
                -- 1 in 1000 chance of dropping a diamond.
                -- Default rarity is '1'.
                rarity = 1000,
                items = {"default:diamond"},
            },
            {
                -- Only drop if using an item whose name is identical to one
                -- of these.
                tools = {"default:shovel_mese", "default:shovel_diamond"},
                rarity = 5,
                items = {"default:dirt"},
                -- Whether all items in the dropped item list inherit the
                -- hardware coloring palette color from the dug node.
                -- Default is 'false'.
                inherit_color = true,
            },
            {
                -- Only drop if using an item whose name contains
                -- "default:shovel_" (this item filtering by string matching
                -- is deprecated, use tool_groups instead).
                tools = {"~default:shovel_"},
                rarity = 2,
                -- The item list dropped.
                items = {"default:sand", "default:desert_sand"},
            },
            {
                -- Only drop if using an item in the "magicwand" group, or
                -- an item that is in both the "pickaxe" and the "lucky"
                -- groups.
                tool_groups = {
                    "magicwand",
                    {"pickaxe", "lucky"}
                },
                items = {"default:coal_lump"},
            },
        },
    },

    on_construct = function(pos),
    -- Node constructor; called after adding node.
    -- Can set up metadata and stuff like that.
    -- Not called for bulk node placement (i.e. schematics and VoxelManip).
    -- Note: Within an on_construct callback, core.set_node can cause an
    -- infinite loop if it invokes the same callback.
    --  Consider using core.swap_node instead.
    -- default: nil

    on_destruct = function(pos),
    -- Node destructor; called before removing node.
    -- Not called for bulk node placement.
    -- default: nil

    after_destruct = function(pos, oldnode),
    -- Node destructor; called after removing node.
    -- Not called for bulk node placement.
    -- default: nil

    on_flood = function(pos, oldnode, newnode),
    -- Called when a liquid (newnode) is about to flood oldnode, if it has
    -- `floodable = true` in the nodedef. Not called for bulk node placement
    -- (i.e. schematics and VoxelManip) or air nodes. If return true the
    -- node is not flooded, but on_flood callback will most likely be called
    -- over and over again every liquid update interval.
    -- Default: nil
    -- Warning: making a liquid node 'floodable' will cause problems.

    preserve_metadata = function(pos, oldnode, oldmeta, drops),
    -- Called when `oldnode` is about be converted to an item, but before the
    -- node is deleted from the world or the drops are added. This is
    -- generally the result of either the node being dug or an attached node
    -- becoming detached.
    -- * `pos`: node position
    -- * `oldnode`: node table of node before it was deleted
    -- * `oldmeta`: metadata of node before it was deleted, as a metadata table
    -- * `drops`: a table of `ItemStack`s, so any metadata to be preserved can
    --   be added directly to one or more of the dropped items. See
    --   "ItemStackMetaRef".
    -- default: `nil`

    after_place_node = function(pos, placer, itemstack, pointed_thing),
    -- Called after constructing node when node was placed using
    -- core.item_place_node / core.place_node.
    -- If return true no item is taken from itemstack.
    -- `placer` may be any valid ObjectRef or nil.
    -- default: nil

    after_dig_node = function(pos, oldnode, oldmetadata, digger),
    -- Called after destructing the node when node was dug using
    -- `core.node_dig` / `core.dig_node`.
    -- * `pos`: node position
    -- * `oldnode`: node table of node before it was dug
    -- * `oldmetadata`: metadata of node before it was dug,
    --                  as a metadata table
    -- * `digger`: ObjectRef of digger
    -- default: nil

    can_dig = function(pos, [player]),
    -- Returns true if node can be dug, or false if not.
    -- default: nil

    on_punch = function(pos, node, puncher, pointed_thing),
    -- default: core.node_punch
    -- Called when puncher (an ObjectRef) punches the node at pos.
    -- By default calls core.register_on_punchnode callbacks.

    on_rightclick = function(pos, node, clicker, itemstack, pointed_thing),
    -- default: nil
    -- Called when clicker (an ObjectRef) used the 'place/build' key
    -- (not necessarily an actual rightclick)
    -- while pointing at the node at pos with 'node' being the node table.
    -- itemstack will hold clicker's wielded item.
    -- Shall return the leftover itemstack.
    -- Note: pointed_thing can be nil, if a mod calls this function.
    -- This function does not get triggered by clients <=0.4.16 if the
    -- "formspec" node metadata field is set.

    on_dig = function(pos, node, digger),
    -- default: core.node_dig
    -- By default checks privileges, wears out item (if tool) and removes node.
    -- return true if the node was dug successfully, false otherwise.
    -- Deprecated: returning nil is the same as returning true.

    on_timer = function(pos, elapsed),
    -- default: nil
    -- called by NodeTimers, see core.get_node_timer and NodeTimerRef.
    -- elapsed is the total time passed since the timer was started.
    -- return true to run the timer for another cycle with the same timeout
    -- value.

    on_receive_fields = function(pos, formname, fields, sender),
    -- fields = {name1 = value1, name2 = value2, ...}
    -- formname should be the empty string; you **must not** use formname.
    -- Called when an UI form (e.g. sign text input) returns data.
    -- See core.register_on_player_receive_fields for more info.
    -- default: nil

    allow_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player),
    -- Called when a player wants to move items inside the inventory.
    -- Return value: number of items allowed to move.

    allow_metadata_inventory_put = function(pos, listname, index, stack, player),
    -- Called when a player wants to put something into the inventory.
    -- Return value: number of items allowed to put.
    -- Return value -1: Allow and don't modify item count in inventory.

    allow_metadata_inventory_take = function(pos, listname, index, stack, player),
    -- Called when a player wants to take something out of the inventory.
    -- Return value: number of items allowed to take.
    -- Return value -1: Allow and don't modify item count in inventory.

    on_metadata_inventory_move = function(pos, from_list, from_index, to_list, to_index, count, player),
    on_metadata_inventory_put = function(pos, listname, index, stack, player),
    on_metadata_inventory_take = function(pos, listname, index, stack, player),
    -- Called after the actual action has happened, according to what was
    -- allowed.
    -- No return value.

    on_blast = function(pos, intensity),
    -- intensity: 1.0 = mid range of regular TNT.
    -- If defined, called when an explosion touches the node, instead of
    -- removing the node.

    mod_origin = "modname",
    -- stores which mod actually registered a node
    -- If the source could not be determined it contains "??"
    -- Useful for getting which mod truly registered something
    -- example: if a node is registered as ":othermodname:nodename",
    -- nodename will show "othermodname", but mod_origin will say "modname"
}

{
    -- 'constant' or 'linear'
    -- (nil defaults to 'constant')
    blend = "linear",
    color_stops = {
        [0.0] = "#ff0000",
        [0.5] = "slateblue",
        [1.0] = {r=0, g=255, b=0, a=150},
    }
}

-- Stone pickaxe
{
    output = "example:stone_pickaxe",
    -- A 3x3 recipe which needs 3 stone in the 1st row,
    -- and 1 stick in the horizontal middle in each of the 2nd and 3nd row.
    -- The 4 remaining slots have to be empty.
    recipe = {
        {"example:stone", "example:stone", "example:stone"}, -- row 1
        {"",              "example:stick", ""             }, -- row 2
        {"",              "example:stick", ""             }, -- row 3
    --   ^ column 1       ^ column 2       ^ column 3
    },
    -- There is no replacements table, so every input item
    -- will be consumed.
}

-- Wet sponge
{
    output = "example:wet_sponge",
    -- 1x2 recipe with a water bucket above a dry sponge
    recipe = {
        {"example:water_bucket"},
        {"example:dry_sponge"},
    },
    -- When the wet sponge is crafted, the water bucket
    -- in the input slot is replaced with an empty
    -- bucket
    replacements = {
        {"example:water_bucket", "example:empty_bucket"},
    },
}

-- Very wet sponge
{
    output = "example:very_wet_sponge",
    -- 3x3 recipe with a wet sponge in the center
    -- and 4 water buckets around it
    recipe = {
        {"","example:water_bucket",""},
        {"example:water_bucket","example:wet_sponge","example:water_bucket"},
        {"","example:water_bucket",""},
    },
    -- When the wet sponge is crafted, all water buckets
    -- in the input slot become empty
    replacements = {
        -- Without these repetitions, only the first
        -- water bucket would be replaced.
        {"example:water_bucket", "example:empty_bucket"},
        {"example:water_bucket", "example:empty_bucket"},
        {"example:water_bucket", "example:empty_bucket"},
        {"example:water_bucket", "example:empty_bucket"},
    },
}

-- Magic book:
-- 3 magic orbs + 1 book crafts a magic book,
-- and the orbs will be replaced with 3 different runes.
{
    output = "example:magic_book",
    -- 3x2 recipe
    recipe = {
        -- 3 items in the group `magic_orb` on top of a book in the middle
        {"group:magic_orb", "group:magic_orb", "group:magic_orb"},
        {"", "example:book", ""},
    },
    -- When the book is crafted, the 3 magic orbs will be turned into
    -- 3 runes: ice rune, earth rune and fire rune (from left to right)
    replacements = {
        {"group:magic_orb", "example:ice_rune"},
        {"group:magic_orb", "example:earth_rune"},
        {"group:magic_orb", "example:fire_rune"},
    },
}

{
    -- Craft a mushroom stew from a bowl, a brown mushroom and a red mushroom
    -- (no matter where in the input grid the items are placed)
    type = "shapeless",
    output = "example:mushroom_stew",
    recipe = {
        "example:bowl",
        "example:mushroom_brown",
        "example:mushroom_red",
    },
}

{
    type = "toolrepair",
    additional_wear = -0.02, -- multiplier of 65536
}

65536 * (1 - ( (1 - tool_1_wear) + (1 - tool_2_wear) + additional_wear))

{
    type = "cooking",
    output = "example:glass",
    recipe = "example:sand",
    cooktime = 3.0,
}

{
    type = "fuel",
    recipe = "example:coal_lump",
    burntime = 20.0,
}

{
    type = "fuel",
    recipe = "example:lava_bucket",
    burntime = 60.0,
    replacements = {{"example:lava_bucket", "example:empty_bucket"}},
}

{
    ore_type = "",
    -- Supported: "scatter", "sheet", "puff", "blob", "vein", "stratum"

    ore = "",
    -- Ore node to place

    ore_param2 = 0,
    -- Param2 to set for ore (e.g. facedir rotation)

    wherein = "",
    -- Node to place ore in. Multiple are possible by passing a list.

    clust_scarcity = 8 * 8 * 8,
    -- Ore has a 1 out of clust_scarcity chance of spawning in a node.
    -- If the desired average distance between ores is 'd', set this to
    -- d * d * d.

    clust_num_ores = 8,
    -- Number of ores in a cluster

    clust_size = 3,
    -- Size of the bounding box of the cluster.
    -- In this example, there is a 3 * 3 * 3 cluster where 8 out of the 27
    -- nodes are coal ore.

    y_min = -31000,
    y_max = 31000,
    -- Lower and upper limits for ore (inclusive)

    flags = "",
    -- Attributes for the ore generation, see 'Ore attributes' section above

    noise_threshold = 0,
    -- If noise is above this threshold, ore is placed. Not needed for a
    -- uniform distribution.

    noise_params = {
        offset = 0,
        scale = 1,
        spread = {x = 100, y = 100, z = 100},
        seed = 23,
        octaves = 3,
        persistence = 0.7
    },
    -- NoiseParams structure describing one of the perlin noises used for
    -- ore distribution.
    -- Needed by "sheet", "puff", "blob" and "vein" ores.
    -- Omit from "scatter" ore for a uniform ore distribution.
    -- Omit from "stratum" ore for a simple horizontal strata from y_min to
    -- y_max.

    biomes = {"desert", "rainforest"},
    -- List of biomes in which this ore occurs.
    -- Occurs in all biomes if this is omitted, and ignored if the Mapgen
    -- being used does not support biomes.
    -- Can be a list of (or a single) biome names, IDs, or definitions.

    -- Type-specific parameters

    -- "sheet"
    column_height_min = 1,
    column_height_max = 16,
    column_midpoint_factor = 0.5,

    -- "puff"
    np_puff_top = {
        offset = 4,
        scale = 2,
        spread = {x = 100, y = 100, z = 100},
        seed = 47,
        octaves = 3,
        persistence = 0.7
    },
    np_puff_bottom = {
        offset = 4,
        scale = 2,
        spread = {x = 100, y = 100, z = 100},
        seed = 11,
        octaves = 3,
        persistence = 0.7
    },

    -- "vein"
    random_factor = 1.0,

    -- "stratum"
    np_stratum_thickness = {
        offset = 8,
        scale = 4,
        spread = {x = 100, y = 100, z = 100},
        seed = 17,
        octaves = 3,
        persistence = 0.7
    },
    stratum_thickness = 8, -- only used if no noise defined
}

{
    name = "tundra",

    node_dust = "default:snow",
    -- Node dropped onto upper surface after all else is generated

    node_top = "default:dirt_with_snow",
    depth_top = 1,
    -- Node forming surface layer of biome and thickness of this layer

    node_filler = "default:permafrost",
    depth_filler = 3,
    -- Node forming lower layer of biome and thickness of this layer

    node_stone = "default:bluestone",
    -- Node that replaces all stone nodes between roughly y_min and y_max.

    node_water_top = "default:ice",
    depth_water_top = 10,
    -- Node forming a surface layer in seawater with the defined thickness

    node_water = "",
    -- Node that replaces all seawater nodes not in the surface layer

    node_river_water = "default:ice",
    -- Node that replaces river water in mapgens that use
    -- default:river_water

    node_riverbed = "default:gravel",
    depth_riverbed = 2,
    -- Node placed under river water and thickness of this layer

    node_cave_liquid = "default:lava_source",
    node_cave_liquid = {"default:water_source", "default:lava_source"},
    -- Nodes placed inside 50% of the medium size caves.
    -- Multiple nodes can be specified, each cave will use a randomly
    -- chosen node from the list.
    -- If this field is left out or 'nil', cave liquids fall back to
    -- classic behavior of lava and water distributed using 3D noise.
    -- For no cave liquid, specify "air".

    node_dungeon = "default:cobble",
    -- Node used for primary dungeon structure.
    -- If absent, dungeon nodes fall back to the 'mapgen_cobble' mapgen
    -- alias, if that is also absent, dungeon nodes fall back to the biome
    -- 'node_stone'.
    -- If present, the following two nodes are also used.

    node_dungeon_alt = "default:mossycobble",
    -- Node used for randomly-distributed alternative structure nodes.
    -- If alternative structure nodes are not wanted leave this absent.

    node_dungeon_stair = "stairs:stair_cobble",
    -- Node used for dungeon stairs.
    -- If absent, stairs fall back to 'node_dungeon'.

    y_max = 31000,
    y_min = 1,
    -- Upper and lower limits for biome.
    -- Alternatively you can use xyz limits as shown below.

    max_pos = {x = 31000, y = 128, z = 31000},
    min_pos = {x = -31000, y = 9, z = -31000},
    -- xyz limits for biome, an alternative to using 'y_min' and 'y_max'.
    -- Biome is limited to a cuboid defined by these positions.
    -- Any x, y or z field left undefined defaults to -31000 in 'min_pos' or
    -- 31000 in 'max_pos'.

    vertical_blend = 8,
    -- Vertical distance in nodes above 'y_max' over which the biome will
    -- blend with the biome above.
    -- Set to 0 for no vertical blend. Defaults to 0.

    heat_point = 0,
    humidity_point = 50,
    -- Characteristic temperature and humidity for the biome.
    -- These values create 'biome points' on a voronoi diagram with heat and
    -- humidity as axes. The resulting voronoi cells determine the
    -- distribution of the biomes.
    -- Heat and humidity have average values of 50, vary mostly between
    -- 0 and 100 but can exceed these values.

    weight = 1.0,
    -- Relative weight of the biome in the Voronoi diagram.
    -- A value of 0 (or less) is ignored and equivalent to 1.0.
}

{
    deco_type = "simple",
    -- Type. "simple", "schematic" or "lsystem" supported

    place_on = "default:dirt_with_grass",
    -- Node (or list of nodes) that the decoration can be placed on

    sidelen = 8,
    -- Size of the square (X / Z) divisions of the mapchunk being generated.
    -- Determines the resolution of noise variation if used.
    -- If the chunk size is not evenly divisible by sidelen, sidelen is made
    -- equal to the chunk size.

    fill_ratio = 0.02,
    -- The value determines 'decorations per surface node'.
    -- Used only if noise_params is not specified.
    -- If >= 10.0 complete coverage is enabled and decoration placement uses
    -- a different and much faster method.

    noise_params = {
        offset = 0,
        scale = 0.45,
        spread = {x = 100, y = 100, z = 100},
        seed = 354,
        octaves = 3,
        persistence = 0.7,
        lacunarity = 2.0,
        flags = "absvalue"
    },
    -- NoiseParams structure describing the perlin noise used for decoration
    -- distribution.
    -- A noise value is calculated for each square division and determines
    -- 'decorations per surface node' within each division.
    -- If the noise value >= 10.0 complete coverage is enabled and
    -- decoration placement uses a different and much faster method.

    biomes = {"Oceanside", "Hills", "Plains"},
    -- List of biomes in which this decoration occurs. Occurs in all biomes
    -- if this is omitted, and ignored if the Mapgen being used does not
    -- support biomes.
    -- Can be a list of (or a single) biome names, IDs, or definitions.

    y_min = -31000,
    y_max = 31000,
    -- Lower and upper limits for decoration (inclusive).
    -- These parameters refer to the Y coordinate of the 'place_on' node.

    spawn_by = "default:water",
    -- Node (or list of nodes) that the decoration only spawns next to.
    -- Checks the 8 neighboring nodes on the same height,
    -- and also the ones at the height plus the check_offset, excluding both center nodes.

    check_offset = -1,
    -- Specifies the offset that spawn_by should also check
    -- The default value of -1 is useful to e.g check for water next to the base node.
    -- 0 disables additional checks, valid values: {-1, 0, 1}

    num_spawn_by = 1,
    -- Number of spawn_by nodes that must be surrounding the decoration
    -- position to occur.
    -- If absent or -1, decorations occur next to any nodes.

    flags = "liquid_surface, force_placement, all_floors, all_ceilings",
    -- Flags for all decoration types.
    -- "liquid_surface": Find the highest liquid (not solid) surface under
    --   open air. Search stops and fails on the first solid node.
    --   Cannot be used with "all_floors" or "all_ceilings" below.
    -- "force_placement": Nodes other than "air" and "ignore" are replaced
    --   by the decoration.
    -- "all_floors", "all_ceilings": Instead of placement on the highest
    --   surface in a mapchunk the decoration is placed on all floor and/or
    --   ceiling surfaces, for example in caves and dungeons.
    --   Ceiling decorations act as an inversion of floor decorations so the
    --   effect of 'place_offset_y' is inverted.
    --   Y-slice probabilities do not function correctly for ceiling
    --   schematic decorations as the behavior is unchanged.
    --   If a single decoration registration has both flags the floor and
    --   ceiling decorations will be aligned vertically.

    ----- Simple-type parameters

    decoration = "default:grass",
    -- The node name used as the decoration.
    -- If instead a list of strings, a randomly selected node from the list
    -- is placed as the decoration.

    height = 1,
    -- Decoration height in nodes.
    -- If height_max is not 0, this is the lower limit of a randomly
    -- selected height.

    height_max = 0,
    -- Upper limit of the randomly selected height.
    -- If absent, the parameter 'height' is used as a constant.

    param2 = 0,
    -- Param2 value of decoration nodes.
    -- If param2_max is not 0, this is the lower limit of a randomly
    -- selected param2.

    param2_max = 0,
    -- Upper limit of the randomly selected param2.
    -- If absent, the parameter 'param2' is used as a constant.

    place_offset_y = 0,
    -- Y offset of the decoration base node relative to the standard base
    -- node position.
    -- Can be positive or negative. Default is 0.
    -- Effect is inverted for "all_ceilings" decorations.
    -- Ignored by 'y_min', 'y_max' and 'spawn_by' checks, which always refer
    -- to the 'place_on' node.

    ----- Schematic-type parameters

    schematic = "foobar.mts",
    -- If schematic is a string, it is the filepath relative to the current
    -- working directory of the specified Luanti schematic file.
    -- Could also be the ID of a previously registered schematic.

    schematic = {
        size = {x = 4, y = 6, z = 4},
        data = {
            {name = "default:cobble", param1 = 255, param2 = 0},
            {name = "default:dirt_with_grass", param1 = 255, param2 = 0},
            {name = "air", param1 = 255, param2 = 0},
              ...
        },
        yslice_prob = {
            {ypos = 2, prob = 128},
            {ypos = 5, prob = 64},
              ...
        },
    },
    -- Alternative schematic specification by supplying a table. The fields
    -- size and data are mandatory whereas yslice_prob is optional.
    -- See 'Schematic specifier' for details.

    replacements = {["oldname"] = "convert_to", ...},
    -- Map of node names to replace in the schematic after reading it.

    flags = "place_center_x, place_center_y, place_center_z",
    -- Flags for schematic decorations. See 'Schematic attributes'.

    rotation = "90",
    -- Rotation can be "0", "90", "180", "270", or "random"

    place_offset_y = 0,
    -- If the flag 'place_center_y' is set this parameter is ignored.
    -- Y offset of the schematic base node layer relative to the 'place_on'
    -- node.
    -- Can be positive or negative. Default is 0.
    -- Effect is inverted for "all_ceilings" decorations.
    -- Ignored by 'y_min', 'y_max' and 'spawn_by' checks, which always refer
    -- to the 'place_on' node.

    ----- L-system-type parameters

    treedef = {},
    -- Same as for `core.spawn_tree`.
    -- See section [L-system trees] for more details.
}

{
    params = "",
    -- Short parameter description.  See the below note.

    description = "",
    -- General description of the command's purpose.

    privs = {},
    -- Required privileges to run. See `core.check_player_privs()` for
    -- the format and see [Privileges] for an overview of privileges.

    func = function(name, param),
    -- Called when command is run.
    -- * `name` is the name of the player who issued the command.
    -- * `param` is a string with the full arguments to the command.
    -- Returns a boolean for success and a string value.
    -- The string is shown to the issuing player upon exit of `func` or,
    -- if `func` returns `false` and no string, the help message is shown.
}

{
    params = "<name> <privilege>",

    description = "Remove privilege from player",

    privs = {privs=true},  -- Require the "privs" privilege to run

    func = function(name, param),
}

{
    description = "",
    -- Privilege description

    give_to_singleplayer = true,
    -- Whether to grant the privilege to singleplayer.

    give_to_admin = true,
    -- Whether to grant the privilege to the server admin.
    -- Uses value of 'give_to_singleplayer' by default.

    on_grant = function(name, granter_name),
    -- Called when given to player 'name' by 'granter_name'.
    -- 'granter_name' will be nil if the priv was granted by a mod.

    on_revoke = function(name, revoker_name),
    -- Called when taken from player 'name' by 'revoker_name'.
    -- 'revoker_name' will be nil if the priv was revoked by a mod.

    -- Note that the above two callbacks will be called twice if a player is
    -- responsible, once with the player name, and then with a nil player
    -- name.
    -- Return true in the above callbacks to stop register_on_priv_grant or
    -- revoke being called.
}

{
    allow_move = function(inv, from_list, from_index, to_list, to_index, count, player),
    -- Called when a player wants to move items inside the inventory.
    -- Return value: number of items allowed to move.

    allow_put = function(inv, listname, index, stack, player),
    -- Called when a player wants to put something into the inventory.
    -- Return value: number of items allowed to put.
    -- Return value -1: Allow and don't modify item count in inventory.

    allow_take = function(inv, listname, index, stack, player),
    -- Called when a player wants to take something out of the inventory.
    -- Return value: number of items allowed to take.
    -- Return value -1: Allow and don't modify item count in inventory.

    on_move = function(inv, from_list, from_index, to_list, to_index, count, player),
    on_put = function(inv, listname, index, stack, player),
    on_take = function(inv, listname, index, stack, player),
    -- Called after the actual action has happened, according to what was
    -- allowed.
    -- No return value.
}

{
    type = "image",
    -- Type of element, can be "compass", "hotbar" (46 ¹), "image", "image_waypoint",
    -- "inventory", "minimap" (44 ¹), "statbar", "text" or "waypoint"
    -- ¹: minimal protocol version for client-side support
    -- If undefined "text" will be used.

    hud_elem_type = "image",
    -- Deprecated, same as `type`.
    -- In case both are specified `type` will be used.

    position = {x=0.5, y=0.5},
    -- Top left corner position of element

    name = "<name>",

    scale = {x = 1, y = 1},

    text = "<text>",

    text2 = "<text>",

    number = 0,

    item = 0,

    direction = 0,
    -- Direction: 0: left-right, 1: right-left, 2: top-bottom, 3: bottom-top

    alignment = {x=0, y=0},

    offset = {x=0, y=0},

    world_pos = {x=0, y=0, z=0},

    size = {x=0, y=0},

    z_index = 0,
    -- Z index: lower z-index HUDs are displayed behind higher z-index HUDs

    style = 0,
}

{
    pos = {x=0, y=0, z=0},
    velocity = {x=0, y=0, z=0},
    acceleration = {x=0, y=0, z=0},
    -- Spawn particle at pos with velocity and acceleration

    expirationtime = 1,
    -- Disappears after expirationtime seconds

    size = 1,
    -- Scales the visual size of the particle texture.
    -- If `node` is set, size can be set to 0 to spawn a randomly-sized
    -- particle (just like actual node dig particles).

    collisiondetection = false,
    -- If true collides with `walkable` nodes and, depending on the
    -- `object_collision` field, objects too.

    collision_removal = false,
    -- If true particle is removed when it collides.
    -- Requires collisiondetection = true to have any effect.

    object_collision = false,
    -- If true particle collides with objects that are defined as
    -- `physical = true,` and `collide_with_objects = true,`.
    -- Requires collisiondetection = true to have any effect.

    vertical = false,
    -- If true faces player using y axis only

    texture = "image.png",
    -- The texture of the particle
    -- v5.6.0 and later: also supports the table format described in the
    -- following section, but due to a bug this did not take effect
    -- (beyond the texture name).
    -- v5.9.0 and later: fixes the bug.
    -- Note: "texture.animation" is ignored here. Use "animation" below instead.

    playername = "singleplayer",
    -- Optional, if specified spawns particle only on the player's client

    animation = {Tile Animation definition},
    -- Optional, specifies how to animate the particle texture

    glow = 0
    -- Optional, specify particle self-luminescence in darkness.
    -- Values 0-14.

    node = {name = "ignore", param2 = 0},
    -- Optional, if specified the particle will have the same appearance as
    -- node dig particles for the given node.
    -- `texture` and `animation` will be ignored if this is set.

    node_tile = 0,
    -- Optional, only valid in combination with `node`
    -- If set to a valid number 1-6, specifies the tile from which the
    -- particle texture is picked.
    -- Otherwise, the default behavior is used. (currently: any random tile)

    drag = {x=0, y=0, z=0},
    -- v5.6.0 and later: Optional drag value, consult the following section
    -- Note: Only a vector is supported here. Alternative forms like a single
    -- number are not supported.

    jitter = {min = ..., max = ..., bias = 0},
    -- v5.6.0 and later: Optional jitter range, consult the following section

    bounce = {min = ..., max = ..., bias = 0},
    -- v5.6.0 and later: Optional bounce range, consult the following section
}

{
    -------------------
    -- Common fields --
    -------------------
    -- (same name and meaning in both new and legacy syntax)

    amount = 1,
    -- Number of particles spawned over the time period `time`.

    time = 1,
    -- Lifespan of spawner in seconds.
    -- If time is 0 spawner has infinite lifespan and spawns the `amount` on
    -- a per-second basis.

    collisiondetection = false,
    -- If true collide with `walkable` nodes and, depending on the
    -- `object_collision` field, objects too.

    collision_removal = false,
    -- If true particles are removed when they collide.
    -- Requires collisiondetection = true to have any effect.

    object_collision = false,
    -- If true particles collide with objects that are defined as
    -- `physical = true,` and `collide_with_objects = true,`.
    -- Requires collisiondetection = true to have any effect.

    attached = ObjectRef,
    -- If defined, particle positions, velocities and accelerations are
    -- relative to this object's position and yaw

    vertical = false,
    -- If true face player using y axis only

    texture = "image.png",
    -- The texture of the particle
    -- v5.6.0 and later: also supports the table format described in the
    -- following section.

    playername = "singleplayer",
    -- Optional, if specified spawns particles only on the player's client

    animation = {Tile Animation definition},
    -- Optional, specifies how to animate the particles' texture
    -- v5.6.0 and later: set length to -1 to synchronize the length
    -- of the animation with the expiration time of individual particles.
    -- (-2 causes the animation to be played twice, and so on)

    glow = 0,
    -- Optional, specify particle self-luminescence in darkness.
    -- Values 0-14.

    node = {name = "ignore", param2 = 0},
    -- Optional, if specified the particles will have the same appearance as
    -- node dig particles for the given node.
    -- `texture` and `animation` will be ignored if this is set.

    node_tile = 0,
    -- Optional, only valid in combination with `node`
    -- If set to a valid number 1-6, specifies the tile from which the
    -- particle texture is picked.
    -- Otherwise, the default behavior is used. (currently: any random tile)

    -------------------
    -- Legacy fields --
    -------------------

    minpos = {x=0, y=0, z=0},
    maxpos = {x=0, y=0, z=0},
    minvel = {x=0, y=0, z=0},
    maxvel = {x=0, y=0, z=0},
    minacc = {x=0, y=0, z=0},
    maxacc = {x=0, y=0, z=0},
    minexptime = 1,
    maxexptime = 1,
    minsize = 1,
    maxsize = 1,
    -- The particles' properties are random values between the min and max
    -- values.
    -- applies to: pos, velocity, acceleration, expirationtime, size
    -- If `node` is set, min and maxsize can be set to 0 to spawn
    -- randomly-sized particles (just like actual node dig particles).
}

{
  -- old syntax
  maxpos = {x = 0, y = 0, z = 0},
  minpos = {x = 0, y = 0, z = 0},

  -- absolute value
  pos = 0,
  -- all components of every particle's position vector will be set to this
  -- value

  -- vec3
  pos = vector.new(0,0,0),
  -- all particles will appear at this exact position throughout the lifetime
  -- of the particlespawner

  -- vec3 range
  pos = {
        -- the particle will appear at a position that is picked at random from
        -- within a cubic range

        min = vector.new(0,0,0),
        -- `min` is the minimum value this property will be set to in particles
        -- spawned by the generator

        max = vector.new(0,0,0),
        -- `max` is the minimum value this property will be set to in particles
        -- spawned by the generator

        bias = 0,
        -- when `bias` is 0, all random values are exactly as likely as any
        -- other. when it is positive, the higher it is, the more likely values
        -- will appear towards the minimum end of the allowed spectrum. when
        -- it is negative, the lower it is, the more likely values will appear
        -- towards the maximum end of the allowed spectrum. the curve is
        -- exponential and there is no particular maximum or minimum value
    },

    -- tween table
    pos_tween = {...},
    -- a tween table should consist of a list of frames in the same form as the
    -- untweened pos property above, which the engine will interpolate between,
    -- and optionally a number of properties that control how the interpolation
    -- takes place. currently **only two frames**, the first and the last, are
    -- used, but extra frames are accepted for the sake of forward compatibility.
    -- any of the above definition styles can be used here as well in any combination
    -- supported by the property type

    pos_tween = {
        style = "fwd",
        -- linear animation from first to last frame (default)
        style = "rev",
        -- linear animation from last to first frame
        style = "pulse",
        -- linear animation from first to last then back to first again
        style = "flicker",
        -- like "pulse", but slightly randomized to add a bit of stutter

        reps = 1,
        -- number of times the animation is played over the particle's lifespan

        start = 0.0,
        -- point in the spawner's lifespan at which the animation begins. 0 is
        -- the very beginning, 1 is the very end

        -- frames can be defined in a number of different ways, depending on the
        -- underlying type of the property. for now, all but the first and last
        -- frame are ignored

        -- frames

            -- floats
            0, 0,

            -- vec3s
            vector.new(0,0,0),
            vector.new(0,0,0),

            -- vec3 ranges
            { min = vector.new(0,0,0), max = vector.new(0,0,0), bias = 0 },
            { min = vector.new(0,0,0), max = vector.new(0,0,0), bias = 0 },

            -- mixed
            0, { min = vector.new(0,0,0), max = vector.new(0,0,0), bias = 0 },
    },
}

texture = {
    name = "mymod_particle_texture.png",
    -- the texture specification string

    alpha = 1.0,
    -- controls how visible the particle is; at 1.0 the particle is fully
    -- visible, at 0, it is completely invisible.

    alpha_tween = {1, 0},
    -- can be used instead of `alpha` to animate the alpha value over the
    -- particle's lifetime. these tween tables work identically to the tween
    -- tables used in particlespawner properties, except that time references
    -- are understood with respect to the particle's lifetime, not the
    -- spawner's. {1,0} fades the particle out over its lifetime.

    scale = 1,
    scale = {x = 1, y = 1},
    -- scales the texture onscreen

    scale_tween = {
        {x = 1, y = 1},
        {x = 0, y = 1},
    },
    -- animates the scale over the particle's lifetime. works like the
    -- alpha_tween table, but can accept two-dimensional vectors as well as
    -- integer values. the example value would cause the particle to shrink
    -- in one dimension over the course of its life until it disappears

    blend = "alpha",
    -- (default) blends transparent pixels with those they are drawn atop
    -- according to the alpha channel of the source texture. useful for
    -- e.g. material objects like rocks, dirt, smoke, or node chunks
    -- note: there will be rendering bugs when particles interact with
    -- translucent nodes. particles are also not transparency-sorted
    -- relative to each other.
    blend = "clip",
    -- pixels are either fully opaque or fully transparent,
    -- depending on whether alpha is greater than or less than 50%
    -- (just like `use_texture_alpha = "clip"` for nodes).
    -- you should prefer this if you don't need semi-transparency, as it's faster.
    blend = "add",
    -- adds the value of pixels to those underneath them, modulo the sources
    -- alpha channel. useful for e.g. bright light effects like sparks or fire
    blend = "screen",
    -- like "add" but less bright. useful for subtler light effects. note that
    -- this is NOT formally equivalent to the "screen" effect used in image
    -- editors and compositors, as it does not respect the alpha channel of
    -- of the image being blended
    blend = "sub",
    -- the inverse of "add"; the value of the source pixel is subtracted from
    -- the pixel underneath it. a white pixel will turn whatever is underneath
    -- it black; a black pixel will be "transparent". useful for creating
    -- darkening effects

    animation = {Tile Animation definition},
    -- overrides the particlespawner's global animation property for a single
    -- specific texture
}

texpool = {
    "mymod_particle_texture.png";
    { name = "mymod_spark.png", alpha_tween = {1, 0} },
    {
      name = "mymod_dust.png",
      alpha = 0.3,
      scale = 1.5,
      animation = {
            type = "vertical_frames",
            aspect_w = 16, aspect_h = 16,

            length = 3,
            -- the animation lasts for 3s and then repeats
            length = -3,
            -- repeat the animation three times over the particle's lifetime
            -- (post-v5.6.0 clients only)
      },
    },
}

alpha_tween = {
    0.0, 1.0,
    style = "pulse",
    reps = 4,
}

{
    url = "http://example.org",

    timeout = 10,
    -- Timeout for request to be completed in seconds. Default depends on engine settings.

    method = "GET", "POST", "PUT" or "DELETE"
    -- The http method to use. Defaults to "GET".

    data = "Raw request data string" OR {field1 = "data1", field2 = "data2"},
    -- Data for the POST, PUT or DELETE request.
    -- Accepts both a string and a table. If a table is specified, encodes
    -- table as x-www-form-urlencoded key-value pairs.

    user_agent = "ExampleUserAgent",
    -- Optional, if specified replaces the default Luanti user agent with
    -- given string

    extra_headers = { "Accept-Language: en-us", "Accept-Charset: utf-8" },
    -- Optional, if specified adds additional headers to the HTTP request.
    -- You must make sure that the header strings follow HTTP specification
    -- ("Key: Value").

    multipart = boolean
    -- Optional, if true performs a multipart HTTP request.
    -- Default is false.
    -- Post only, data must be array

    post_data = "Raw POST request data string" OR {field1 = "data1", field2 = "data2"},
    -- Deprecated, use `data` instead. Forces `method = "POST"`.
}

{
    completed = true,
    -- If true, the request has finished (either succeeded, failed or timed
    -- out)

    succeeded = true,
    -- If true, the request was successful

    timeout = false,
    -- If true, the request timed out

    code = 200,
    -- HTTP status code

    data = "response"
}

{
    get_auth = function(name),
    -- Get authentication data for existing player `name` (`nil` if player
    -- doesn't exist).
    -- Returns following structure:
    -- `{password=<string>, privileges=<table>, last_login=<number or nil>}`

    create_auth = function(name, password),
    -- Create new auth data for player `name`.
    -- Note that `password` is not plain-text but an arbitrary
    -- representation decided by the engine.

    delete_auth = function(name),
    -- Delete auth data of player `name`.
    -- Returns boolean indicating success (false if player is nonexistent).

    set_password = function(name, password),
    -- Set password of player `name` to `password`.
    -- Auth data should be created if not present.

    set_privileges = function(name, privileges),
    -- Set privileges of player `name`.
    -- `privileges` is in table form: keys are privilege names, values are `true`;
    -- auth data should be created if not present.

    reload = function(),
    -- Reload authentication data from the storage location.
    -- Returns boolean indicating success.

    record_login = function(name),
    -- Called when player joins, used for keeping track of last_login

    iterate = function(),
    -- Returns an iterator (use with `for` loops) for all player names
    -- currently in the auth database
}