Initial commit

builtin/game/async.lua

@@ -0,0 +1,22 @@
+
+core.async_jobs = {}
+
+function core.async_event_handler(jobid, retval)
+	local callback = core.async_jobs[jobid]
+	assert(type(callback) == "function")
+	callback(unpack(retval, 1, retval.n))
+	core.async_jobs[jobid] = nil
+end
+
+function core.handle_async(func, callback, ...)
+	assert(type(func) == "function" and type(callback) == "function",
+		"Invalid minetest.handle_async invocation")
+	local args = {n = select("#", ...), ...}
+	local mod_origin = core.get_last_run_mod()
+
+	local jobid = core.do_async_callback(func, args, mod_origin)
+	core.async_jobs[jobid] = callback
+
+	return true
+end
+

builtin/game/auth.lua

@@ -0,0 +1,185 @@
+-- Minetest: builtin/auth.lua
+
+--
+-- Builtin authentication handler
+--
+
+-- Make the auth object private, deny access to mods
+local core_auth = core.auth
+core.auth = nil
+
+core.builtin_auth_handler = {
+	get_auth = function(name)
+		assert(type(name) == "string")
+		local auth_entry = core_auth.read(name)
+		-- If no such auth found, return nil
+		if not auth_entry then
+			return nil
+		end
+		-- Figure out what privileges the player should have.
+		-- Take a copy of the privilege table
+		local privileges = {}
+		for priv, _ in pairs(auth_entry.privileges) do
+			privileges[priv] = true
+		end
+		-- If singleplayer, give all privileges except those marked as give_to_singleplayer = false
+		if core.is_singleplayer() then
+			for priv, def in pairs(core.registered_privileges) do
+				if def.give_to_singleplayer then
+					privileges[priv] = true
+				end
+			end
+		-- For the admin, give everything
+		elseif name == core.settings:get("name") then
+			for priv, def in pairs(core.registered_privileges) do
+				if def.give_to_admin then
+					privileges[priv] = true
+				end
+			end
+		end
+		-- All done
+		return {
+			password = auth_entry.password,
+			privileges = privileges,
+			last_login = auth_entry.last_login,
+		}
+	end,
+	create_auth = function(name, password)
+		assert(type(name) == "string")
+		assert(type(password) == "string")
+		core.log('info', "Built-in authentication handler adding player '"..name.."'")
+		return core_auth.create({
+			name = name,
+			password = password,
+			privileges = core.string_to_privs(core.settings:get("default_privs")),
+			last_login = -1,  -- Defer login time calculation until record_login (called by on_joinplayer)
+		})
+	end,
+	delete_auth = function(name)
+		assert(type(name) == "string")
+		local auth_entry = core_auth.read(name)
+		if not auth_entry then
+			return false
+		end
+		core.log('info', "Built-in authentication handler deleting player '"..name.."'")
+		return core_auth.delete(name)
+	end,
+	set_password = function(name, password)
+		assert(type(name) == "string")
+		assert(type(password) == "string")
+		local auth_entry = core_auth.read(name)
+		if not auth_entry then
+			core.builtin_auth_handler.create_auth(name, password)
+		else
+			core.log('info', "Built-in authentication handler setting password of player '"..name.."'")
+			auth_entry.password = password
+			core_auth.save(auth_entry)
+		end
+		return true
+	end,
+	set_privileges = function(name, privileges)
+		assert(type(name) == "string")
+		assert(type(privileges) == "table")
+		local auth_entry = core_auth.read(name)
+		if not auth_entry then
+			auth_entry = core.builtin_auth_handler.create_auth(name,
+				core.get_password_hash(name,
+					core.settings:get("default_password")))
+		end
+
+		auth_entry.privileges = privileges
+
+		core_auth.save(auth_entry)
+
+		-- Run grant callbacks
+		for priv, _ in pairs(privileges) do
+			if not auth_entry.privileges[priv] then
+				core.run_priv_callbacks(name, priv, nil, "grant")
+			end
+		end
+
+		-- Run revoke callbacks
+		for priv, _ in pairs(auth_entry.privileges) do
+			if not privileges[priv] then
+				core.run_priv_callbacks(name, priv, nil, "revoke")
+			end
+		end
+		core.notify_authentication_modified(name)
+	end,
+	reload = function()
+		core_auth.reload()
+		return true
+	end,
+	record_login = function(name)
+		assert(type(name) == "string")
+		local auth_entry = core_auth.read(name)
+		assert(auth_entry)
+		auth_entry.last_login = os.time()
+		core_auth.save(auth_entry)
+	end,
+	iterate = function()
+		local names = {}
+		local nameslist = core_auth.list_names()
+		for k,v in pairs(nameslist) do
+			names[v] = true
+		end
+		return pairs(names)
+	end,
+}
+
+core.register_on_prejoinplayer(function(name, ip)
+	if core.registered_auth_handler ~= nil then
+		return -- Don't do anything if custom auth handler registered
+	end
+	local auth_entry = core_auth.read(name)
+	if auth_entry ~= nil then
+		return
+	end
+
+	local name_lower = name:lower()
+	for k in core.builtin_auth_handler.iterate() do
+		if k:lower() == name_lower then
+			return string.format("\nCannot create new player called '%s'. "..
+					"Another account called '%s' is already registered. "..
+					"Please check the spelling if it's your account "..
+					"or use a different nickname.", name, k)
+		end
+	end
+end)
+
+--
+-- Authentication API
+--
+
+function core.register_authentication_handler(handler)
+	if core.registered_auth_handler then
+		error("Add-on authentication handler already registered by "..core.registered_auth_handler_modname)
+	end
+	core.registered_auth_handler = handler
+	core.registered_auth_handler_modname = core.get_current_modname()
+	handler.mod_origin = core.registered_auth_handler_modname
+end
+
+function core.get_auth_handler()
+	return core.registered_auth_handler or core.builtin_auth_handler
+end
+
+local function auth_pass(name)
+	return function(...)
+		local auth_handler = core.get_auth_handler()
+		if auth_handler[name] then
+			return auth_handler[name](...)
+		end
+		return false
+	end
+end
+
+core.set_player_password = auth_pass("set_password")
+core.set_player_privs    = auth_pass("set_privileges")
+core.remove_player_auth  = auth_pass("delete_auth")
+core.auth_reload         = auth_pass("reload")
+
+local record_login = auth_pass("record_login")
+core.register_on_joinplayer(function(player)
+	record_login(player:get_player_name())
+end)

builtin/game/constants.lua

@@ -0,0 +1,31 @@
+-- Minetest: builtin/constants.lua
+
+--
+-- Constants values for use with the Lua API
+--
+
+-- mapnode.h
+-- Built-in Content IDs (for use with VoxelManip API)
+core.CONTENT_UNKNOWN = 125
+core.CONTENT_AIR     = 126
+core.CONTENT_IGNORE  = 127
+
+-- emerge.h
+-- Block emerge status constants (for use with core.emerge_area)
+core.EMERGE_CANCELLED   = 0
+core.EMERGE_ERRORED     = 1
+core.EMERGE_FROM_MEMORY = 2
+core.EMERGE_FROM_DISK   = 3
+core.EMERGE_GENERATED   = 4
+
+-- constants.h
+-- Size of mapblocks in nodes
+core.MAP_BLOCKSIZE = 16
+-- Default maximal HP of a player
+core.PLAYER_MAX_HP_DEFAULT = 20
+-- Default maximal breath of a player
+core.PLAYER_MAX_BREATH_DEFAULT = 10
+
+-- light.h
+-- Maximum value for node 'light_source' parameter
+core.LIGHT_MAX = 14

builtin/game/deprecated.lua

@@ -0,0 +1,65 @@
+-- Minetest: builtin/deprecated.lua
+
+--
+-- EnvRef
+--
+core.env = {}
+local envref_deprecation_message_printed = false
+setmetatable(core.env, {
+	__index = function(table, key)
+		if not envref_deprecation_message_printed then
+			core.log("deprecated", "core.env:[...] is deprecated and should be replaced with core.[...]")
+			envref_deprecation_message_printed = true
+		end
+		local func = core[key]
+		if type(func) == "function" then
+			rawset(table, key, function(self, ...)
+				return func(...)
+			end)
+		else
+			rawset(table, key, nil)
+		end
+		return rawget(table, key)
+	end
+})
+
+function core.rollback_get_last_node_actor(pos, range, seconds)
+	return core.rollback_get_node_actions(pos, range, seconds, 1)[1]
+end
+
+--
+-- core.setting_*
+--
+
+local settings = core.settings
+
+local function setting_proxy(name)
+	return function(...)
+		core.log("deprecated", "WARNING: minetest.setting_* "..
+			"functions are deprecated.  "..
+			"Use methods on the minetest.settings object.")
+		return settings[name](settings, ...)
+	end
+end
+
+core.setting_set = setting_proxy("set")
+core.setting_get = setting_proxy("get")
+core.setting_setbool = setting_proxy("set_bool")
+core.setting_getbool = setting_proxy("get_bool")
+core.setting_save = setting_proxy("write")
+
+--
+-- core.register_on_auth_fail
+--
+
+function core.register_on_auth_fail(func)
+	core.log("deprecated", "core.register_on_auth_fail " ..
+		"is deprecated and should be replaced by " ..
+		"core.register_on_authplayer instead.")
+
+	core.register_on_authplayer(function (player_name, ip, is_success)
+		if not is_success then
+			func(player_name, ip)
+		end
+	end)
+end

builtin/game/detached_inventory.lua

@@ -0,0 +1,24 @@
+-- Minetest: builtin/detached_inventory.lua
+
+core.detached_inventories = {}
+
+function core.create_detached_inventory(name, callbacks, player_name)
+	local stuff = {}
+	stuff.name = name
+	if callbacks then
+		stuff.allow_move = callbacks.allow_move
+		stuff.allow_put = callbacks.allow_put
+		stuff.allow_take = callbacks.allow_take
+		stuff.on_move = callbacks.on_move
+		stuff.on_put = callbacks.on_put
+		stuff.on_take = callbacks.on_take
+	end
+	stuff.mod_origin = core.get_current_modname() or "??"
+	core.detached_inventories[name] = stuff
+	return core.create_detached_inventory_raw(name, player_name)
+end
+
+function core.remove_detached_inventory(name)
+	core.detached_inventories[name] = nil
+	return core.remove_detached_inventory_raw(name)
+end

builtin/game/falling.lua

@@ -0,0 +1,608 @@
+-- Minetest: builtin/item.lua
+
+local builtin_shared = ...
+local SCALE = 0.667
+
+local facedir_to_euler = {
+	{y = 0, x = 0, z = 0},
+	{y = -math.pi/2, x = 0, z = 0},
+	{y = math.pi, x = 0, z = 0},
+	{y = math.pi/2, x = 0, z = 0},
+	{y = math.pi/2, x = -math.pi/2, z = math.pi/2},
+	{y = math.pi/2, x = math.pi, z = math.pi/2},
+	{y = math.pi/2, x = math.pi/2, z = math.pi/2},
+	{y = math.pi/2, x = 0, z = math.pi/2},
+	{y = -math.pi/2, x = math.pi/2, z = math.pi/2},
+	{y = -math.pi/2, x = 0, z = math.pi/2},
+	{y = -math.pi/2, x = -math.pi/2, z = math.pi/2},
+	{y = -math.pi/2, x = math.pi, z = math.pi/2},
+	{y = 0, x = 0, z = math.pi/2},
+	{y = 0, x = -math.pi/2, z = math.pi/2},
+	{y = 0, x = math.pi, z = math.pi/2},
+	{y = 0, x = math.pi/2, z = math.pi/2},
+	{y = math.pi, x = math.pi, z = math.pi/2},
+	{y = math.pi, x = math.pi/2, z = math.pi/2},
+	{y = math.pi, x = 0, z = math.pi/2},
+	{y = math.pi, x = -math.pi/2, z = math.pi/2},
+	{y = math.pi, x = math.pi, z = 0},
+	{y = -math.pi/2, x = math.pi, z = 0},
+	{y = 0, x = math.pi, z = 0},
+	{y = math.pi/2, x = math.pi, z = 0}
+}
+
+local gravity = tonumber(core.settings:get("movement_gravity")) or 9.81
+
+--
+-- Falling stuff
+--
+
+core.register_entity(":__builtin:falling_node", {
+	initial_properties = {
+		visual = "item",
+		visual_size = vector.new(SCALE, SCALE, SCALE),
+		textures = {},
+		physical = true,
+		is_visible = false,
+		collide_with_objects = true,
+		collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
+	},
+
+	node = {},
+	meta = {},
+	floats = false,
+
+	set_node = function(self, node, meta)
+		node.param2 = node.param2 or 0
+		self.node = node
+		meta = meta or {}
+		if type(meta.to_table) == "function" then
+			meta = meta:to_table()
+		end
+		for _, list in pairs(meta.inventory or {}) do
+			for i, stack in pairs(list) do
+				if type(stack) == "userdata" then
+					list[i] = stack:to_string()
+				end
+			end
+		end
+		local def = core.registered_nodes[node.name]
+		if not def then
+			-- Don't allow unknown nodes to fall
+			core.log("info",
+				"Unknown falling node removed at "..
+				core.pos_to_string(self.object:get_pos()))
+			self.object:remove()
+			return
+		end
+		self.meta = meta
+
+		-- Cache whether we're supposed to float on water
+		self.floats = core.get_item_group(node.name, "float") ~= 0
+
+		-- Set entity visuals
+		if def.drawtype == "torchlike" or def.drawtype == "signlike" then
+			local textures
+			if def.tiles and def.tiles[1] then
+				local tile = def.tiles[1]
+				if type(tile) == "table" then
+					tile = tile.name
+				end
+				if def.drawtype == "torchlike" then
+					textures = { "("..tile..")^[transformFX", tile }
+				else
+					textures = { tile, "("..tile..")^[transformFX" }
+				end
+			end
+			local vsize
+			if def.visual_scale then
+				local s = def.visual_scale
+				vsize = vector.new(s, s, s)
+			end
+			self.object:set_properties({
+				is_visible = true,
+				visual = "upright_sprite",
+				visual_size = vsize,
+				textures = textures,
+				glow = def.light_source,
+			})
+		elseif def.drawtype ~= "airlike" then
+			local itemstring = node.name
+			if core.is_colored_paramtype(def.paramtype2) then
+				itemstring = core.itemstring_with_palette(itemstring, node.param2)
+			end
+			-- FIXME: solution needed for paramtype2 == "leveled"
+			-- Calculate size of falling node
+			local s = {}
+			s.x = (def.visual_scale or 1) * SCALE
+			s.y = s.x
+			s.z = s.x
+			-- Compensate for wield_scale
+			if def.wield_scale then
+				s.x = s.x / def.wield_scale.x
+				s.y = s.y / def.wield_scale.y
+				s.z = s.z / def.wield_scale.z
+			end
+			self.object:set_properties({
+				is_visible = true,
+				wield_item = itemstring,
+				visual_size = s,
+				glow = def.light_source,
+			})
+		end
+
+		-- Set collision box (certain nodeboxes only for now)
+		local nb_types = {fixed=true, leveled=true, connected=true}
+		if def.drawtype == "nodebox" and def.node_box and
+			nb_types[def.node_box.type] and def.node_box.fixed then
+			local box = table.copy(def.node_box.fixed)
+			if type(box[1]) == "table" then
+				box = #box == 1 and box[1] or nil -- We can only use a single box
+			end
+			if box then
+				if def.paramtype2 == "leveled" and (self.node.level or 0) > 0 then
+					box[5] = -0.5 + self.node.level / 64
+				end
+				self.object:set_properties({
+					collisionbox = box
+				})
+			end
+		end
+
+		-- Rotate entity
+		if def.drawtype == "torchlike" then
+			self.object:set_yaw(math.pi*0.25)
+		elseif ((node.param2 ~= 0 or def.drawtype == "nodebox" or def.drawtype == "mesh")
+				and (def.wield_image == "" or def.wield_image == nil))
+				or def.drawtype == "signlike"
+				or def.drawtype == "mesh"
+				or def.drawtype == "normal"
+				or def.drawtype == "nodebox" then
+			if (def.paramtype2 == "facedir" or def.paramtype2 == "colorfacedir") then
+				local fdir = node.param2 % 32 % 24
+				-- Get rotation from a precalculated lookup table
+				local euler = facedir_to_euler[fdir + 1]
+				self.object:set_rotation(euler)
+			elseif (def.drawtype ~= "plantlike" and def.drawtype ~= "plantlike_rooted" and
+					(def.paramtype2 == "wallmounted" or def.paramtype2 == "colorwallmounted" or def.drawtype == "signlike")) then
+				local rot = node.param2 % 8
+				if (def.drawtype == "signlike" and def.paramtype2 ~= "wallmounted" and def.paramtype2 ~= "colorwallmounted") then
+					-- Change rotation to "floor" by default for non-wallmounted paramtype2
+					rot = 1
+				end
+				local pitch, yaw, roll = 0, 0, 0
+				if def.drawtype == "nodebox" or def.drawtype == "mesh" then
+					if rot == 0 then
+						pitch, yaw = math.pi/2, 0
+					elseif rot == 1 then
+						pitch, yaw = -math.pi/2, math.pi
+					elseif rot == 2 then
+						pitch, yaw = 0, math.pi/2
+					elseif rot == 3 then
+						pitch, yaw = 0, -math.pi/2
+					elseif rot == 4 then
+						pitch, yaw = 0, math.pi
+					end
+				else
+					if rot == 1 then
+						pitch, yaw = math.pi, math.pi
+					elseif rot == 2 then
+						pitch, yaw = math.pi/2, math.pi/2
+					elseif rot == 3 then
+						pitch, yaw = math.pi/2, -math.pi/2
+					elseif rot == 4 then
+						pitch, yaw = math.pi/2, math.pi
+					elseif rot == 5 then
+						pitch, yaw = math.pi/2, 0
+					end
+				end
+				if def.drawtype == "signlike" then
+					pitch = pitch - math.pi/2
+					if rot == 0 then
+						yaw = yaw + math.pi/2
+					elseif rot == 1 then
+						yaw = yaw - math.pi/2
+					end
+				elseif def.drawtype == "mesh" or def.drawtype == "normal" or def.drawtype == "nodebox" then
+					if rot >= 0 and rot <= 1 then
+						roll = roll + math.pi
+					else
+						yaw = yaw + math.pi
+					end
+				end
+				self.object:set_rotation({x=pitch, y=yaw, z=roll})
+			elseif (def.drawtype == "mesh" and def.paramtype2 == "degrotate") then
+				local p2 = (node.param2 - (def.place_param2 or 0)) % 240
+				local yaw = (p2 / 240) * (math.pi * 2)
+				self.object:set_yaw(yaw)
+			elseif (def.drawtype == "mesh" and def.paramtype2 == "colordegrotate") then
+				local p2 = (node.param2 % 32 - (def.place_param2 or 0) % 32) % 24
+				local yaw = (p2 / 24) * (math.pi * 2)
+				self.object:set_yaw(yaw)
+			end
+		end
+	end,
+
+	get_staticdata = function(self)
+		local ds = {
+			node = self.node,
+			meta = self.meta,
+		}
+		return core.serialize(ds)
+	end,
+
+	on_activate = function(self, staticdata)
+		self.object:set_armor_groups({immortal = 1})
+		self.object:set_acceleration(vector.new(0, -gravity, 0))
+
+		local ds = core.deserialize(staticdata)
+		if ds and ds.node then
+			self:set_node(ds.node, ds.meta)
+		elseif ds then
+			self:set_node(ds)
+		elseif staticdata ~= "" then
+			self:set_node({name = staticdata})
+		end
+	end,
+
+	try_place = function(self, bcp, bcn)
+		local bcd = core.registered_nodes[bcn.name]
+		-- Add levels if dropped on same leveled node
+		if bcd and bcd.paramtype2 == "leveled" and
+				bcn.name == self.node.name then
+			local addlevel = self.node.level
+			if (addlevel or 0) <= 0 then
+				addlevel = bcd.leveled
+			end
+			if core.add_node_level(bcp, addlevel) < addlevel then
+				return true
+			elseif bcd.buildable_to then
+				-- Node level has already reached max, don't place anything
+				return true
+			end
+		end
+
+		-- Decide if we're replacing the node or placing on top
+		local np = vector.copy(bcp)
+		if bcd and bcd.buildable_to and
+				(not self.floats or bcd.liquidtype == "none") then
+			core.remove_node(bcp)
+		else
+			np.y = np.y + 1
+		end
+
+		-- Check what's here
+		local n2 = core.get_node(np)
+		local nd = core.registered_nodes[n2.name]
+		-- If it's not air or liquid, remove node and replace it with
+		-- it's drops
+		if n2.name ~= "air" and (not nd or nd.liquidtype == "none") then
+			if nd and nd.buildable_to == false then
+				nd.on_dig(np, n2, nil)
+				-- If it's still there, it might be protected
+				if core.get_node(np).name == n2.name then
+					return false
+				end
+			else
+				core.remove_node(np)
+			end
+		end
+
+		-- Create node
+		local def = core.registered_nodes[self.node.name]
+		if def then
+			core.add_node(np, self.node)
+			if self.meta then
+				core.get_meta(np):from_table(self.meta)
+			end
+			if def.sounds and def.sounds.place then
+				core.sound_play(def.sounds.place, {pos = np}, true)
+			end
+		end
+		core.check_for_falling(np)
+		return true
+	end,
+
+	on_step = function(self, dtime, moveresult)
+		-- Fallback code since collision detection can't tell us
+		-- about liquids (which do not collide)
+		if self.floats then
+			local pos = self.object:get_pos()
+
+			local bcp = pos:offset(0, -0.7, 0):round()
+			local bcn = core.get_node(bcp)
+
+			local bcd = core.registered_nodes[bcn.name]
+			if bcd and bcd.liquidtype ~= "none" then
+				if self:try_place(bcp, bcn) then
+					self.object:remove()
+					return
+				end
+			end
+		end
+
+		assert(moveresult)
+		if not moveresult.collides then
+			return -- Nothing to do :)
+		end
+
+		local bcp, bcn
+		local player_collision
+		if moveresult.touching_ground then
+			for _, info in ipairs(moveresult.collisions) do
+				if info.type == "object" then
+					if info.axis == "y" and info.object:is_player() then
+						player_collision = info
+					end
+				elseif info.axis == "y" then
+					bcp = info.node_pos
+					bcn = core.get_node(bcp)
+					break
+				end
+			end
+		end
+
+		if not bcp then
+			-- We're colliding with something, but not the ground. Irrelevant to us.
+			if player_collision then
+				-- Continue falling through players by moving a little into
+				-- their collision box
+				-- TODO: this hack could be avoided in the future if objects
+				--       could choose who to collide with
+				local vel = self.object:get_velocity()
+				self.object:set_velocity(vector.new(
+					vel.x,
+					player_collision.old_velocity.y,
+					vel.z
+				))
+				self.object:set_pos(self.object:get_pos():offset(0, -0.5, 0))
+			end
+			return
+		elseif bcn.name == "ignore" then
+			-- Delete on contact with ignore at world edges
+			self.object:remove()
+			return
+		end
+
+		local failure = false
+
+		local pos = self.object:get_pos()
+		local distance = vector.apply(vector.subtract(pos, bcp), math.abs)
+		if distance.x >= 1 or distance.z >= 1 then
+			-- We're colliding with some part of a node that's sticking out
+			-- Since we don't want to visually teleport, drop as item
+			failure = true
+		elseif distance.y >= 2 then
+			-- Doors consist of a hidden top node and a bottom node that is
+			-- the actual door. Despite the top node being solid, the moveresult
+			-- almost always indicates collision with the bottom node.
+			-- Compensate for this by checking the top node
+			bcp.y = bcp.y + 1
+			bcn = core.get_node(bcp)
+			local def = core.registered_nodes[bcn.name]
+			if not (def and def.walkable) then
+				failure = true -- This is unexpected, fail
+			end
+		end
+
+		-- Try to actually place ourselves
+		if not failure then
+			failure = not self:try_place(bcp, bcn)
+		end
+
+		if failure then
+			local drops = core.get_node_drops(self.node, "")
+			for _, item in pairs(drops) do
+				core.add_item(pos, item)
+			end
+		end
+		self.object:remove()
+	end
+})
+
+local function convert_to_falling_node(pos, node)
+	local obj = core.add_entity(pos, "__builtin:falling_node")
+	if not obj then
+		return false
+	end
+	-- remember node level, the entities' set_node() uses this
+	node.level = core.get_node_level(pos)
+	local meta = core.get_meta(pos)
+	local metatable = meta and meta:to_table() or {}
+
+	local def = core.registered_nodes[node.name]
+	if def and def.sounds and def.sounds.fall then
+		core.sound_play(def.sounds.fall, {pos = pos}, true)
+	end
+
+	obj:get_luaentity():set_node(node, metatable)
+	core.remove_node(pos)
+	return true, obj
+end
+
+function core.spawn_falling_node(pos)
+	local node = core.get_node(pos)
+	if node.name == "air" or node.name == "ignore" then
+		return false
+	end
+	return convert_to_falling_node(pos, node)
+end
+
+local function drop_attached_node(p)
+	local n = core.get_node(p)
+	local drops = core.get_node_drops(n, "")
+	local def = core.registered_items[n.name]
+	if def and def.preserve_metadata then
+		local oldmeta = core.get_meta(p):to_table().fields
+		-- Copy pos and node because the callback can modify them.
+		local pos_copy = vector.copy(p)
+		local node_copy = {name=n.name, param1=n.param1, param2=n.param2}
+		local drop_stacks = {}
+		for k, v in pairs(drops) do
+			drop_stacks[k] = ItemStack(v)
+		end
+		drops = drop_stacks
+		def.preserve_metadata(pos_copy, node_copy, oldmeta, drops)
+	end
+	if def and def.sounds and def.sounds.fall then
+		core.sound_play(def.sounds.fall, {pos = p}, true)
+	end
+	core.remove_node(p)
+	for _, item in pairs(drops) do
+		local pos = {
+			x = p.x + math.random()/2 - 0.25,
+			y = p.y + math.random()/2 - 0.25,
+			z = p.z + math.random()/2 - 0.25,
+		}
+		core.add_item(pos, item)
+	end
+end
+
+function builtin_shared.check_attached_node(p, n)
+	local def = core.registered_nodes[n.name]
+	local d = vector.zero()
+	if def.paramtype2 == "wallmounted" or
+			def.paramtype2 == "colorwallmounted" then
+		-- The fallback vector here is in case 'wallmounted to dir' is nil due
+		-- to voxelmanip placing a wallmounted node without resetting a
+		-- pre-existing param2 value that is out-of-range for wallmounted.
+		-- The fallback vector corresponds to param2 = 0.
+		d = core.wallmounted_to_dir(n.param2) or vector.new(0, 1, 0)
+	else
+		d.y = -1
+	end
+	local p2 = vector.add(p, d)
+	local nn = core.get_node(p2).name
+	local def2 = core.registered_nodes[nn]
+	if def2 and not def2.walkable then
+		return false
+	end
+	return true
+end
+
+--
+-- Some common functions
+--
+
+function core.check_single_for_falling(p)
+	local n = core.get_node(p)
+	if core.get_item_group(n.name, "falling_node") ~= 0 then
+		local p_bottom = vector.offset(p, 0, -1, 0)
+		-- Only spawn falling node if node below is loaded
+		local n_bottom = core.get_node_or_nil(p_bottom)
+		local d_bottom = n_bottom and core.registered_nodes[n_bottom.name]
+		if d_bottom then
+			local same = n.name == n_bottom.name
+			-- Let leveled nodes fall if it can merge with the bottom node
+			if same and d_bottom.paramtype2 == "leveled" and
+					core.get_node_level(p_bottom) <
+					core.get_node_max_level(p_bottom) then
+				convert_to_falling_node(p, n)
+				return true
+			end
+			-- Otherwise only if the bottom node is considered "fall through"
+			if not same and
+					(not d_bottom.walkable or d_bottom.buildable_to) and
+					(core.get_item_group(n.name, "float") == 0 or
+					d_bottom.liquidtype == "none") then
+				convert_to_falling_node(p, n)
+				return true
+			end
+		end
+	end
+
+	if core.get_item_group(n.name, "attached_node") ~= 0 then
+		if not builtin_shared.check_attached_node(p, n) then
+			drop_attached_node(p)
+			return true
+		end
+	end
+
+	return false
+end
+
+-- This table is specifically ordered.
+-- We don't walk diagonals, only our direct neighbors, and self.
+-- Down first as likely case, but always before self. The same with sides.
+-- Up must come last, so that things above self will also fall all at once.
+local check_for_falling_neighbors = {
+	vector.new(-1, -1,  0),
+	vector.new( 1, -1,  0),
+	vector.new( 0, -1, -1),
+	vector.new( 0, -1,  1),
+	vector.new( 0, -1,  0),
+	vector.new(-1,  0,  0),
+	vector.new( 1,  0,  0),
+	vector.new( 0,  0,  1),
+	vector.new( 0,  0, -1),
+	vector.new( 0,  0,  0),
+	vector.new( 0,  1,  0),
+}
+
+function core.check_for_falling(p)
+	-- Round p to prevent falling entities to get stuck.
+	p = vector.round(p)
+
+	-- We make a stack, and manually maintain size for performance.
+	-- Stored in the stack, we will maintain tables with pos, and
+	-- last neighbor visited. This way, when we get back to each
+	-- node, we know which directions we have already walked, and
+	-- which direction is the next to walk.
+	local s = {}
+	local n = 0
+	-- The neighbor order we will visit from our table.
+	local v = 1
+
+	while true do
+		-- Push current pos onto the stack.
+		n = n + 1
+		s[n] = {p = p, v = v}
+		-- Select next node from neighbor list.
+		p = vector.add(p, check_for_falling_neighbors[v])
+		-- Now we check out the node. If it is in need of an update,
+		-- it will let us know in the return value (true = updated).
+		if not core.check_single_for_falling(p) then
+			-- If we don't need to "recurse" (walk) to it then pop
+			-- our previous pos off the stack and continue from there,
+			-- with the v value we were at when we last were at that
+			-- node
+			repeat
+				local pop = s[n]
+				p = pop.p
+				v = pop.v
+				s[n] = nil
+				n = n - 1
+				-- If there's nothing left on the stack, and no
+				-- more sides to walk to, we're done and can exit
+				if n == 0 and v == 11 then
+					return
+				end
+			until v < 11
+			-- The next round walk the next neighbor in list.
+			v = v + 1
+		else
+			-- If we did need to walk the neighbor, then
+			-- start walking it from the walk order start (1),
+			-- and not the order we just pushed up the stack.
+			v = 1
+		end
+	end
+end
+
+--
+-- Global callbacks
+--
+
+local function on_placenode(p, node)
+	core.check_for_falling(p)
+end
+core.register_on_placenode(on_placenode)
+
+local function on_dignode(p, node)
+	core.check_for_falling(p)
+end
+core.register_on_dignode(on_dignode)
+
+local function on_punchnode(p, node)
+	core.check_for_falling(p)
+end
+core.register_on_punchnode(on_punchnode)

builtin/game/features.lua

@@ -0,0 +1,46 @@
+-- Minetest: builtin/features.lua
+
+core.features = {
+	glasslike_framed = true,
+	nodebox_as_selectionbox = true,
+	get_all_craft_recipes_works = true,
+	use_texture_alpha = true,
+	no_legacy_abms = true,
+	texture_names_parens = true,
+	area_store_custom_ids = true,
+	add_entity_with_staticdata = true,
+	no_chat_message_prediction = true,
+	object_use_texture_alpha = true,
+	object_independent_selectionbox = true,
+	httpfetch_binary_data = true,
+	formspec_version_element = true,
+	area_store_persistent_ids = true,
+	pathfinder_works = true,
+	object_step_has_moveresult = true,
+	direct_velocity_on_players = true,
+	use_texture_alpha_string_modes = true,
+	degrotate_240_steps = true,
+	abm_min_max_y = true,
+	particlespawner_tweenable = true,
+	dynamic_add_media_table = true,
+	get_sky_as_table = true,
+}
+
+function core.has_feature(arg)
+	if type(arg) == "table" then
+		local missing_features = {}
+		local result = true
+		for ftr in pairs(arg) do
+			if not core.features[ftr] then
+				missing_features[ftr] = true
+				result = false
+			end
+		end
+		return result, missing_features
+	elseif type(arg) == "string" then
+		if not core.features[arg] then
+			return false, {[arg]=true}
+		end
+		return true, {}
+	end
+end

builtin/game/forceloading.lua

@@ -0,0 +1,126 @@
+-- Prevent anyone else accessing those functions
+local forceload_block = core.forceload_block
+local forceload_free_block = core.forceload_free_block
+core.forceload_block = nil
+core.forceload_free_block = nil
+
+local blocks_forceloaded
+local blocks_temploaded = {}
+local total_forceloaded = 0
+
+-- true, if the forceloaded blocks got changed (flag for persistence on-disk)
+local forceload_blocks_changed = false
+
+local BLOCKSIZE = core.MAP_BLOCKSIZE
+local function get_blockpos(pos)
+	return {
+		x = math.floor(pos.x/BLOCKSIZE),
+		y = math.floor(pos.y/BLOCKSIZE),
+		z = math.floor(pos.z/BLOCKSIZE)}
+end
+
+-- When we create/free a forceload, it's either transient or persistent. We want
+-- to add to/remove from the table that corresponds to the type of forceload, but
+-- we also need the other table because whether we forceload a block depends on
+-- both tables.
+-- This function returns the "primary" table we are adding to/removing from, and
+-- the other table.
+local function get_relevant_tables(transient)
+	if transient then
+		return blocks_temploaded, blocks_forceloaded
+	else
+		return blocks_forceloaded, blocks_temploaded
+	end
+end
+
+function core.forceload_block(pos, transient)
+	-- set changed flag
+	forceload_blocks_changed = true
+
+	local blockpos = get_blockpos(pos)
+	local hash = core.hash_node_position(blockpos)
+	local relevant_table, other_table = get_relevant_tables(transient)
+	if relevant_table[hash] ~= nil then
+		relevant_table[hash] = relevant_table[hash] + 1
+		return true
+	elseif other_table[hash] ~= nil then
+		relevant_table[hash] = 1
+	else
+		if total_forceloaded >= (tonumber(core.settings:get("max_forceloaded_blocks")) or 16) then
+			return false
+		end
+		total_forceloaded = total_forceloaded+1
+		relevant_table[hash] = 1
+		forceload_block(blockpos)
+		return true
+	end
+end
+
+function core.forceload_free_block(pos, transient)
+	-- set changed flag
+	forceload_blocks_changed = true
+
+	local blockpos = get_blockpos(pos)
+	local hash = core.hash_node_position(blockpos)
+	local relevant_table, other_table = get_relevant_tables(transient)
+	if relevant_table[hash] == nil then return end
+	if relevant_table[hash] > 1 then
+		relevant_table[hash] = relevant_table[hash] - 1
+	elseif other_table[hash] ~= nil then
+		relevant_table[hash] = nil
+	else
+		total_forceloaded = total_forceloaded-1
+		relevant_table[hash] = nil
+		forceload_free_block(blockpos)
+	end
+end
+
+-- Keep the forceloaded areas after restart
+local wpath = core.get_worldpath()
+local function read_file(filename)
+	local f = io.open(filename, "r")
+	if f==nil then return {} end
+	local t = f:read("*all")
+	f:close()
+	if t=="" or t==nil then return {} end
+	return core.deserialize(t) or {}
+end
+
+blocks_forceloaded = read_file(wpath.."/force_loaded.txt")
+for _, __ in pairs(blocks_forceloaded) do
+	total_forceloaded = total_forceloaded + 1
+end
+
+core.after(5, function()
+	for hash, _ in pairs(blocks_forceloaded) do
+		local blockpos = core.get_position_from_hash(hash)
+		forceload_block(blockpos)
+	end
+end)
+
+-- persists the currently forceloaded blocks to disk
+local function persist_forceloaded_blocks()
+	local data = core.serialize(blocks_forceloaded)
+	core.safe_file_write(wpath.."/force_loaded.txt", data)
+end
+
+-- periodical forceload persistence
+local function periodically_persist_forceloaded_blocks()
+
+	-- only persist if the blocks actually changed
+	if forceload_blocks_changed then
+		persist_forceloaded_blocks()
+
+		-- reset changed flag
+		forceload_blocks_changed = false
+	end
+
+	-- recheck after some time
+	core.after(10, periodically_persist_forceloaded_blocks)
+end
+
+-- persist periodically
+core.after(5, periodically_persist_forceloaded_blocks)
+
+-- persist on shutdown
+core.register_on_shutdown(persist_forceloaded_blocks)

builtin/game/init.lua

@@ -0,0 +1,40 @@
+
+local scriptpath = core.get_builtin_path()
+local commonpath = scriptpath .. "common" .. DIR_DELIM
+local gamepath   = scriptpath .. "game".. DIR_DELIM
+
+-- Shared between builtin files, but
+-- not exposed to outer context
+local builtin_shared = {}
+
+dofile(gamepath .. "constants.lua")
+dofile(gamepath .. "item_s.lua")
+assert(loadfile(gamepath .. "item.lua"))(builtin_shared)
+dofile(gamepath .. "register.lua")
+
+if core.settings:get_bool("profiler.load") then
+	profiler = dofile(scriptpath .. "profiler" .. DIR_DELIM .. "init.lua")
+end
+
+dofile(commonpath .. "after.lua")
+dofile(commonpath .. "mod_storage.lua")
+dofile(gamepath .. "item_entity.lua")
+dofile(gamepath .. "deprecated.lua")
+dofile(gamepath .. "misc_s.lua")
+dofile(gamepath .. "misc.lua")
+dofile(gamepath .. "privileges.lua")
+dofile(gamepath .. "auth.lua")
+dofile(commonpath .. "chatcommands.lua")
+dofile(gamepath .. "chat.lua")
+dofile(commonpath .. "information_formspecs.lua")
+dofile(gamepath .. "static_spawn.lua")
+dofile(gamepath .. "detached_inventory.lua")
+assert(loadfile(gamepath .. "falling.lua"))(builtin_shared)
+dofile(gamepath .. "features.lua")
+dofile(gamepath .. "voxelarea.lua")
+dofile(gamepath .. "forceloading.lua")
+dofile(gamepath .. "statbars.lua")
+dofile(gamepath .. "knockback.lua")
+dofile(gamepath .. "async.lua")
+
+profiler = nil

builtin/game/item.lua

@@ -0,0 +1,680 @@
+-- Minetest: builtin/item.lua
+
+local builtin_shared = ...
+
+local function copy_pointed_thing(pointed_thing)
+	return {
+		type  = pointed_thing.type,
+		above = pointed_thing.above and vector.copy(pointed_thing.above),
+		under = pointed_thing.under and vector.copy(pointed_thing.under),
+		ref   = pointed_thing.ref,
+	}
+end
+
+--
+-- Item definition helpers
+--
+
+function core.get_pointed_thing_position(pointed_thing, above)
+	if pointed_thing.type == "node" then
+		if above then
+			-- The position where a node would be placed
+			return pointed_thing.above
+		end
+		-- The position where a node would be dug
+		return pointed_thing.under
+	elseif pointed_thing.type == "object" then
+		return pointed_thing.ref and pointed_thing.ref:get_pos()
+	end
+end
+
+local function has_all_groups(tbl, required_groups)
+	if type(required_groups) == "string" then
+		return (tbl[required_groups] or 0) ~= 0
+	end
+	for _, group in ipairs(required_groups) do
+		if (tbl[group] or 0) == 0 then
+			return false
+		end
+	end
+	return true
+end
+
+function core.get_node_drops(node, toolname)
+	-- Compatibility, if node is string
+	local nodename = node
+	local param2 = 0
+	-- New format, if node is table
+	if (type(node) == "table") then
+		nodename = node.name
+		param2 = node.param2
+	end
+	local def = core.registered_nodes[nodename]
+	local drop = def and def.drop
+	local ptype = def and def.paramtype2
+	-- get color, if there is color (otherwise nil)
+	local palette_index = core.strip_param2_color(param2, ptype)
+	if drop == nil then
+		-- default drop
+		if palette_index then
+			local stack = ItemStack(nodename)
+			stack:get_meta():set_int("palette_index", palette_index)
+			return {stack:to_string()}
+		end
+		return {nodename}
+	elseif type(drop) == "string" then
+		-- itemstring drop
+		return drop ~= "" and {drop} or {}
+	elseif drop.items == nil then
+		-- drop = {} to disable default drop
+		return {}
+	end
+
+	-- Extended drop table
+	local got_items = {}
+	local got_count = 0
+	for _, item in ipairs(drop.items) do
+		local good_rarity = true
+		local good_tool = true
+		if item.rarity ~= nil then
+			good_rarity = item.rarity < 1 or math.random(item.rarity) == 1
+		end
+		if item.tools ~= nil or item.tool_groups ~= nil then
+			good_tool = false
+		end
+		if item.tools ~= nil and toolname then
+			for _, tool in ipairs(item.tools) do
+				if tool:sub(1, 1) == '~' then
+					good_tool = toolname:find(tool:sub(2)) ~= nil
+				else
+					good_tool = toolname == tool
+				end
+				if good_tool then
+					break
+				end
+			end
+		end
+		if item.tool_groups ~= nil and toolname then
+			local tooldef = core.registered_items[toolname]
+			if tooldef ~= nil and type(tooldef.groups) == "table" then
+				if type(item.tool_groups) == "string" then
+					-- tool_groups can be a string which specifies the required group
+					good_tool = core.get_item_group(toolname, item.tool_groups) ~= 0
+				else
+					-- tool_groups can be a list of sufficient requirements.
+					-- i.e. if any item in the list can be satisfied then the tool is good
+					assert(type(item.tool_groups) == "table")
+					for _, required_groups in ipairs(item.tool_groups) do
+						-- required_groups can be either a string (a single group),
+						-- or an array of strings where all must be in tooldef.groups
+						good_tool = has_all_groups(tooldef.groups, required_groups)
+						if good_tool then
+							break
+						end
+					end
+				end
+			end
+		end
+		if good_rarity and good_tool then
+			got_count = got_count + 1
+			for _, add_item in ipairs(item.items) do
+				-- add color, if necessary
+				if item.inherit_color and palette_index then
+					local stack = ItemStack(add_item)
+					stack:get_meta():set_int("palette_index", palette_index)
+					add_item = stack:to_string()
+				end
+				got_items[#got_items+1] = add_item
+			end
+			if drop.max_items ~= nil and got_count == drop.max_items then
+				break
+			end
+		end
+	end
+	return got_items
+end
+
+local function user_name(user)
+	return user and user:get_player_name() or ""
+end
+
+-- Returns a logging function. For empty names, does not log.
+local function make_log(name)
+	return name ~= "" and core.log or function() end
+end
+
+function core.item_place_node(itemstack, placer, pointed_thing, param2,
+		prevent_after_place)
+	local def = itemstack:get_definition()
+	if def.type ~= "node" or pointed_thing.type ~= "node" then
+		return itemstack, nil
+	end
+
+	local under = pointed_thing.under
+	local oldnode_under = core.get_node_or_nil(under)
+	local above = pointed_thing.above
+	local oldnode_above = core.get_node_or_nil(above)
+	local playername = user_name(placer)
+	local log = make_log(playername)
+
+	if not oldnode_under or not oldnode_above then
+		log("info", playername .. " tried to place"
+			.. " node in unloaded position " .. core.pos_to_string(above))
+		return itemstack, nil
+	end
+
+	local olddef_under = core.registered_nodes[oldnode_under.name]
+	olddef_under = olddef_under or core.nodedef_default
+	local olddef_above = core.registered_nodes[oldnode_above.name]
+	olddef_above = olddef_above or core.nodedef_default
+
+	if not olddef_above.buildable_to and not olddef_under.buildable_to then
+		log("info", playername .. " tried to place"
+			.. " node in invalid position " .. core.pos_to_string(above)
+			.. ", replacing " .. oldnode_above.name)
+		return itemstack, nil
+	end
+
+	-- Place above pointed node
+	local place_to = vector.copy(above)
+
+	-- If node under is buildable_to, place into it instead (eg. snow)
+	if olddef_under.buildable_to then
+		log("info", "node under is buildable to")
+		place_to = vector.copy(under)
+	end
+
+	if core.is_protected(place_to, playername) then
+		log("action", playername
+				.. " tried to place " .. def.name
+				.. " at protected position "
+				.. core.pos_to_string(place_to))
+		core.record_protection_violation(place_to, playername)
+		return itemstack, nil
+	end
+
+	local oldnode = core.get_node(place_to)
+	local newnode = {name = def.name, param1 = 0, param2 = param2 or 0}
+
+	-- Calculate direction for wall mounted stuff like torches and signs
+	if def.place_param2 ~= nil then
+		newnode.param2 = def.place_param2
+	elseif (def.paramtype2 == "wallmounted" or
+			def.paramtype2 == "colorwallmounted") and not param2 then
+		local dir = vector.subtract(under, above)
+		newnode.param2 = core.dir_to_wallmounted(dir)
+	-- Calculate the direction for furnaces and chests and stuff
+	elseif (def.paramtype2 == "facedir" or
+			def.paramtype2 == "colorfacedir") and not param2 then
+		local placer_pos = placer and placer:get_pos()
+		if placer_pos then
+			local dir = vector.subtract(above, placer_pos)
+			newnode.param2 = core.dir_to_facedir(dir)
+			log("info", "facedir: " .. newnode.param2)
+		end
+	end
+
+	local metatable = itemstack:get_meta():to_table().fields
+
+	-- Transfer color information
+	if metatable.palette_index and not def.place_param2 then
+		local color_divisor = nil
+		if def.paramtype2 == "color" then
+			color_divisor = 1
+		elseif def.paramtype2 == "colorwallmounted" then
+			color_divisor = 8
+		elseif def.paramtype2 == "colorfacedir" then
+			color_divisor = 32
+		elseif def.paramtype2 == "colordegrotate" then
+			color_divisor = 32
+		end
+		if color_divisor then
+			local color = math.floor(metatable.palette_index / color_divisor)
+			local other = newnode.param2 % color_divisor
+			newnode.param2 = color * color_divisor + other
+		end
+	end
+
+	-- Check if the node is attached and if it can be placed there
+	if core.get_item_group(def.name, "attached_node") ~= 0 and
+		not builtin_shared.check_attached_node(place_to, newnode) then
+		log("action", "attached node " .. def.name ..
+			" can not be placed at " .. core.pos_to_string(place_to))
+		return itemstack, nil
+	end
+
+	log("action", playername .. " places node "
+		.. def.name .. " at " .. core.pos_to_string(place_to))
+
+	-- Add node and update
+	core.add_node(place_to, newnode)
+
+	-- Play sound if it was done by a player
+	if playername ~= "" and def.sounds and def.sounds.place then
+		core.sound_play(def.sounds.place, {
+			pos = place_to,
+			exclude_player = playername,
+		}, true)
+	end
+
+	local take_item = true
+
+	-- Run callback
+	if def.after_place_node and not prevent_after_place then
+		-- Deepcopy place_to and pointed_thing because callback can modify it
+		local place_to_copy = vector.copy(place_to)
+		local pointed_thing_copy = copy_pointed_thing(pointed_thing)
+		if def.after_place_node(place_to_copy, placer, itemstack,
+				pointed_thing_copy) then
+			take_item = false
+		end
+	end
+
+	-- Run script hook
+	for _, callback in ipairs(core.registered_on_placenodes) do
+		-- Deepcopy pos, node and pointed_thing because callback can modify them
+		local place_to_copy = vector.copy(place_to)
+		local newnode_copy = {name=newnode.name, param1=newnode.param1, param2=newnode.param2}
+		local oldnode_copy = {name=oldnode.name, param1=oldnode.param1, param2=oldnode.param2}
+		local pointed_thing_copy = copy_pointed_thing(pointed_thing)
+		if callback(place_to_copy, newnode_copy, placer, oldnode_copy, itemstack, pointed_thing_copy) then
+			take_item = false
+		end
+	end
+
+	if take_item then
+		itemstack:take_item()
+	end
+	return itemstack, place_to
+end
+
+-- deprecated, item_place does not call this
+function core.item_place_object(itemstack, placer, pointed_thing)
+	local pos = core.get_pointed_thing_position(pointed_thing, true)
+	if pos ~= nil then
+		local item = itemstack:take_item()
+		core.add_item(pos, item)
+	end
+	return itemstack
+end
+
+function core.item_place(itemstack, placer, pointed_thing, param2)
+	-- Call on_rightclick if the pointed node defines it
+	if pointed_thing.type == "node" and placer and
+			not placer:get_player_control().sneak then
+		local n = core.get_node(pointed_thing.under)
+		local nn = n.name
+		if core.registered_nodes[nn] and core.registered_nodes[nn].on_rightclick then
+			return core.registered_nodes[nn].on_rightclick(pointed_thing.under, n,
+					placer, itemstack, pointed_thing) or itemstack, nil
+		end
+	end
+
+	-- Place if node, otherwise do nothing
+	if itemstack:get_definition().type == "node" then
+		return core.item_place_node(itemstack, placer, pointed_thing, param2)
+	end
+	return itemstack, nil
+end
+
+function core.item_secondary_use(itemstack, placer)
+	return itemstack
+end
+
+function core.item_drop(itemstack, dropper, pos)
+	local dropper_is_player = dropper and dropper:is_player()
+	local p = table.copy(pos)
+	local cnt = itemstack:get_count()
+	if dropper_is_player then
+		p.y = p.y + 1.2
+	end
+	local item = itemstack:take_item(cnt)
+	local obj = core.add_item(p, item)
+	if obj then
+		if dropper_is_player then
+			local dir = dropper:get_look_dir()
+			dir.x = dir.x * 2.9
+			dir.y = dir.y * 2.9 + 2
+			dir.z = dir.z * 2.9
+			obj:set_velocity(dir)
+			obj:get_luaentity().dropped_by = dropper:get_player_name()
+		end
+		return itemstack
+	end
+	-- If we reach this, adding the object to the
+	-- environment failed
+end
+
+function core.do_item_eat(hp_change, replace_with_item, itemstack, user, pointed_thing)
+	for _, callback in pairs(core.registered_on_item_eats) do
+		local result = callback(hp_change, replace_with_item, itemstack, user, pointed_thing)
+		if result then
+			return result
+		end
+	end
+	-- read definition before potentially emptying the stack
+	local def = itemstack:get_definition()
+	if itemstack:take_item():is_empty() then
+		return itemstack
+	end
+
+	if def and def.sound and def.sound.eat then
+		core.sound_play(def.sound.eat, {
+			pos = user:get_pos(),
+			max_hear_distance = 16
+		}, true)
+	end
+
+	-- Changing hp might kill the player causing mods to do who-knows-what to the
+	-- inventory, so do this before set_hp().
+	if replace_with_item then
+		if itemstack:is_empty() then
+			itemstack:add_item(replace_with_item)
+		else
+			local inv = user:get_inventory()
+			-- Check if inv is null, since non-players don't have one
+			if inv and inv:room_for_item("main", {name=replace_with_item}) then
+				inv:add_item("main", replace_with_item)
+			else
+				local pos = user:get_pos()
+				pos.y = math.floor(pos.y + 0.5)
+				core.add_item(pos, replace_with_item)
+			end
+		end
+	end
+	user:set_wielded_item(itemstack)
+
+	user:set_hp(user:get_hp() + hp_change)
+
+	return nil -- don't overwrite wield item a second time
+end
+
+function core.item_eat(hp_change, replace_with_item)
+	return function(itemstack, user, pointed_thing)  -- closure
+		if user then
+			return core.do_item_eat(hp_change, replace_with_item, itemstack, user, pointed_thing)
+		end
+	end
+end
+
+function core.node_punch(pos, node, puncher, pointed_thing)
+	-- Run script hook
+	for _, callback in ipairs(core.registered_on_punchnodes) do
+		-- Copy pos and node because callback can modify them
+		local pos_copy = vector.copy(pos)
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		local pointed_thing_copy = pointed_thing and copy_pointed_thing(pointed_thing) or nil
+		callback(pos_copy, node_copy, puncher, pointed_thing_copy)
+	end
+end
+
+function core.handle_node_drops(pos, drops, digger)
+	-- Add dropped items to object's inventory
+	local inv = digger and digger:get_inventory()
+	local give_item
+	if inv then
+		give_item = function(item)
+			return inv:add_item("main", item)
+		end
+	else
+		give_item = function(item)
+			-- itemstring to ItemStack for left:is_empty()
+			return ItemStack(item)
+		end
+	end
+
+	for _, dropped_item in pairs(drops) do
+		local left = give_item(dropped_item)
+		if not left:is_empty() then
+			local p = vector.offset(pos,
+				math.random()/2-0.25,
+				math.random()/2-0.25,
+				math.random()/2-0.25
+			)
+			core.add_item(p, left)
+		end
+	end
+end
+
+function core.node_dig(pos, node, digger)
+	local diggername = user_name(digger)
+	local log = make_log(diggername)
+	local def = core.registered_nodes[node.name]
+	-- Copy pos because the callback could modify it
+	if def and (not def.diggable or
+			(def.can_dig and not def.can_dig(vector.copy(pos), digger))) then
+		log("info", diggername .. " tried to dig "
+			.. node.name .. " which is not diggable "
+			.. core.pos_to_string(pos))
+		return false
+	end
+
+	if core.is_protected(pos, diggername) then
+		log("action", diggername
+				.. " tried to dig " .. node.name
+				.. " at protected position "
+				.. core.pos_to_string(pos))
+		core.record_protection_violation(pos, diggername)
+		return false
+	end
+
+	log('action', diggername .. " digs "
+		.. node.name .. " at " .. core.pos_to_string(pos))
+
+	local wielded = digger and digger:get_wielded_item()
+	local drops = core.get_node_drops(node, wielded and wielded:get_name())
+
+	if wielded then
+		local wdef = wielded:get_definition()
+		local tp = wielded:get_tool_capabilities()
+		local dp = core.get_dig_params(def and def.groups, tp, wielded:get_wear())
+		if wdef and wdef.after_use then
+			wielded = wdef.after_use(wielded, digger, node, dp) or wielded
+		else
+			-- Wear out tool
+			if not core.is_creative_enabled(diggername) then
+				wielded:add_wear(dp.wear)
+				if wielded:get_count() == 0 and wdef.sound and wdef.sound.breaks then
+					core.sound_play(wdef.sound.breaks, {
+						pos = pos,
+						gain = 0.5
+					}, true)
+				end
+			end
+		end
+		digger:set_wielded_item(wielded)
+	end
+
+	-- Check to see if metadata should be preserved.
+	if def and def.preserve_metadata then
+		local oldmeta = core.get_meta(pos):to_table().fields
+		-- Copy pos and node because the callback can modify them.
+		local pos_copy = vector.copy(pos)
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		local drop_stacks = {}
+		for k, v in pairs(drops) do
+			drop_stacks[k] = ItemStack(v)
+		end
+		drops = drop_stacks
+		def.preserve_metadata(pos_copy, node_copy, oldmeta, drops)
+	end
+
+	-- Handle drops
+	core.handle_node_drops(pos, drops, digger)
+
+	local oldmetadata = nil
+	if def and def.after_dig_node then
+		oldmetadata = core.get_meta(pos):to_table()
+	end
+
+	-- Remove node and update
+	core.remove_node(pos)
+
+	-- Play sound if it was done by a player
+	if diggername ~= "" and def and def.sounds and def.sounds.dug then
+		core.sound_play(def.sounds.dug, {
+			pos = pos,
+			exclude_player = diggername,
+		}, true)
+	end
+
+	-- Run callback
+	if def and def.after_dig_node then
+		-- Copy pos and node because callback can modify them
+		local pos_copy = vector.copy(pos)
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		def.after_dig_node(pos_copy, node_copy, oldmetadata, digger)
+	end
+
+	-- Run script hook
+	for _, callback in ipairs(core.registered_on_dignodes) do
+		local origin = core.callback_origins[callback]
+		core.set_last_run_mod(origin.mod)
+
+		-- Copy pos and node because callback can modify them
+		local pos_copy = vector.copy(pos)
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		callback(pos_copy, node_copy, digger)
+	end
+
+	return true
+end
+
+function core.itemstring_with_palette(item, palette_index)
+	local stack = ItemStack(item) -- convert to ItemStack
+	stack:get_meta():set_int("palette_index", palette_index)
+	return stack:to_string()
+end
+
+function core.itemstring_with_color(item, colorstring)
+	local stack = ItemStack(item) -- convert to ItemStack
+	stack:get_meta():set_string("color", colorstring)
+	return stack:to_string()
+end
+
+-- This is used to allow mods to redefine core.item_place and so on
+-- NOTE: This is not the preferred way. Preferred way is to provide enough
+--       callbacks to not require redefining global functions. -celeron55
+local function redef_wrapper(table, name)
+	return function(...)
+		return table[name](...)
+	end
+end
+
+--
+-- Item definition defaults
+--
+
+local default_stack_max = tonumber(core.settings:get("default_stack_max")) or 99
+
+core.nodedef_default = {
+	-- Item properties
+	type="node",
+	-- name intentionally not defined here
+	description = "",
+	groups = {},
+	inventory_image = "",
+	wield_image = "",
+	wield_scale = vector.new(1, 1, 1),
+	stack_max = default_stack_max,
+	usable = false,
+	liquids_pointable = false,
+	tool_capabilities = nil,
+	node_placement_prediction = nil,
+
+	-- Interaction callbacks
+	on_place = redef_wrapper(core, 'item_place'), -- core.item_place
+	on_drop = redef_wrapper(core, 'item_drop'), -- core.item_drop
+	on_use = nil,
+	can_dig = nil,
+
+	on_punch = redef_wrapper(core, 'node_punch'), -- core.node_punch
+	on_rightclick = nil,
+	on_dig = redef_wrapper(core, 'node_dig'), -- core.node_dig
+
+	on_receive_fields = nil,
+
+	-- Node properties
+	drawtype = "normal",
+	visual_scale = 1.0,
+	tiles = nil,
+	special_tiles = nil,
+	post_effect_color = {a=0, r=0, g=0, b=0},
+	paramtype = "none",
+	paramtype2 = "none",
+	is_ground_content = true,
+	sunlight_propagates = false,
+	walkable = true,
+	pointable = true,
+	diggable = true,
+	climbable = false,
+	buildable_to = false,
+	floodable = false,
+	liquidtype = "none",
+	liquid_alternative_flowing = "",
+	liquid_alternative_source = "",
+	liquid_viscosity = 0,
+	drowning = 0,
+	light_source = 0,
+	damage_per_second = 0,
+	selection_box = {type="regular"},
+	legacy_facedir_simple = false,
+	legacy_wallmounted = false,
+}
+
+core.craftitemdef_default = {
+	type="craft",
+	-- name intentionally not defined here
+	description = "",
+	groups = {},
+	inventory_image = "",
+	wield_image = "",
+	wield_scale = vector.new(1, 1, 1),
+	stack_max = default_stack_max,
+	liquids_pointable = false,
+	tool_capabilities = nil,
+
+	-- Interaction callbacks
+	on_place = redef_wrapper(core, 'item_place'), -- core.item_place
+	on_drop = redef_wrapper(core, 'item_drop'), -- core.item_drop
+	on_secondary_use = redef_wrapper(core, 'item_secondary_use'),
+	on_use = nil,
+}
+
+core.tooldef_default = {
+	type="tool",
+	-- name intentionally not defined here
+	description = "",
+	groups = {},
+	inventory_image = "",
+	wield_image = "",
+	wield_scale = vector.new(1, 1, 1),
+	stack_max = 1,
+	liquids_pointable = false,
+	tool_capabilities = nil,
+
+	-- Interaction callbacks
+	on_place = redef_wrapper(core, 'item_place'), -- core.item_place
+	on_secondary_use = redef_wrapper(core, 'item_secondary_use'),
+	on_drop = redef_wrapper(core, 'item_drop'), -- core.item_drop
+	on_use = nil,
+}
+
+core.noneitemdef_default = {  -- This is used for the hand and unknown items
+	type="none",
+	-- name intentionally not defined here
+	description = "",
+	groups = {},
+	inventory_image = "",
+	wield_image = "",
+	wield_scale = vector.new(1, 1, 1),
+	stack_max = default_stack_max,
+	liquids_pointable = false,
+	tool_capabilities = nil,
+
+	-- Interaction callbacks
+	on_place = redef_wrapper(core, 'item_place'),
+	on_secondary_use = redef_wrapper(core, 'item_secondary_use'),
+	on_drop = nil,
+	on_use = nil,
+}

builtin/game/item_entity.lua

@@ -0,0 +1,333 @@
+-- Minetest: builtin/item_entity.lua
+
+function core.spawn_item(pos, item)
+	-- Take item in any format
+	local stack = ItemStack(item)
+	local obj = core.add_entity(pos, "__builtin:item")
+	-- Don't use obj if it couldn't be added to the map.
+	if obj then
+		obj:get_luaentity():set_item(stack:to_string())
+	end
+	return obj
+end
+
+-- If item_entity_ttl is not set, enity will have default life time
+-- Setting it to -1 disables the feature
+
+local time_to_live = tonumber(core.settings:get("item_entity_ttl")) or 900
+local gravity = tonumber(core.settings:get("movement_gravity")) or 9.81
+
+
+core.register_entity(":__builtin:item", {
+	initial_properties = {
+		hp_max = 1,
+		physical = true,
+		collide_with_objects = false,
+		collisionbox = {-0.3, -0.3, -0.3, 0.3, 0.3, 0.3},
+		visual = "wielditem",
+		visual_size = {x = 0.4, y = 0.4},
+		textures = {""},
+		is_visible = false,
+	},
+
+	itemstring = "",
+	moving_state = true,
+	physical_state = true,
+	-- Item expiry
+	age = 0,
+	-- Pushing item out of solid nodes
+	force_out = nil,
+	force_out_start = nil,
+
+	set_item = function(self, item)
+		local stack = ItemStack(item or self.itemstring)
+		self.itemstring = stack:to_string()
+		if self.itemstring == "" then
+			-- item not yet known
+			return
+		end
+
+		-- Backwards compatibility: old clients use the texture
+		-- to get the type of the item
+		local itemname = stack:is_known() and stack:get_name() or "unknown"
+
+		local max_count = stack:get_stack_max()
+		local count = math.min(stack:get_count(), max_count)
+		local size = 0.2 + 0.1 * (count / max_count) ^ (1 / 3)
+		local def = core.registered_items[itemname]
+		local glow = def and def.light_source and
+			math.floor(def.light_source / 2 + 0.5)
+
+		local size_bias = 1e-3 * math.random() -- small random bias to counter Z-fighting
+		local c = {-size, -size, -size, size, size, size}
+		self.object:set_properties({
+			is_visible = true,
+			visual = "wielditem",
+			textures = {itemname},
+			visual_size = {x = size + size_bias, y = size + size_bias},
+			collisionbox = c,
+			automatic_rotate = math.pi * 0.5 * 0.2 / size,
+			wield_item = self.itemstring,
+			glow = glow,
+		})
+
+		-- cache for usage in on_step
+		self._collisionbox = c
+	end,
+
+	get_staticdata = function(self)
+		return core.serialize({
+			itemstring = self.itemstring,
+			age = self.age,
+			dropped_by = self.dropped_by
+		})
+	end,
+
+	on_activate = function(self, staticdata, dtime_s)
+		if string.sub(staticdata, 1, string.len("return")) == "return" then
+			local data = core.deserialize(staticdata)
+			if data and type(data) == "table" then
+				self.itemstring = data.itemstring
+				self.age = (data.age or 0) + dtime_s
+				self.dropped_by = data.dropped_by
+			end
+		else
+			self.itemstring = staticdata
+		end
+		self.object:set_armor_groups({immortal = 1})
+		self.object:set_velocity({x = 0, y = 2, z = 0})
+		self.object:set_acceleration({x = 0, y = -gravity, z = 0})
+		self._collisionbox = self.initial_properties.collisionbox
+		self:set_item()
+	end,
+
+	try_merge_with = function(self, own_stack, object, entity)
+		if self.age == entity.age then
+			-- Can not merge with itself
+			return false
+		end
+
+		local stack = ItemStack(entity.itemstring)
+		local name = stack:get_name()
+		if own_stack:get_name() ~= name or
+				own_stack:get_meta() ~= stack:get_meta() or
+				own_stack:get_wear() ~= stack:get_wear() or
+				own_stack:get_free_space() == 0 then
+			-- Can not merge different or full stack
+			return false
+		end
+
+		local count = own_stack:get_count()
+		local total_count = stack:get_count() + count
+		local max_count = stack:get_stack_max()
+
+		if total_count > max_count then
+			return false
+		end
+		-- Merge the remote stack into this one
+
+		local pos = object:get_pos()
+		pos.y = pos.y + ((total_count - count) / max_count) * 0.15
+		self.object:move_to(pos)
+
+		self.age = 0 -- Handle as new entity
+		own_stack:set_count(total_count)
+		self:set_item(own_stack)
+
+		entity.itemstring = ""
+		object:remove()
+		return true
+	end,
+
+	enable_physics = function(self)
+		if not self.physical_state then
+			self.physical_state = true
+			self.object:set_properties({physical = true})
+			self.object:set_velocity({x=0, y=0, z=0})
+			self.object:set_acceleration({x=0, y=-gravity, z=0})
+		end
+	end,
+
+	disable_physics = function(self)
+		if self.physical_state then
+			self.physical_state = false
+			self.object:set_properties({physical = false})
+			self.object:set_velocity({x=0, y=0, z=0})
+			self.object:set_acceleration({x=0, y=0, z=0})
+		end
+	end,
+
+	on_step = function(self, dtime, moveresult)
+		self.age = self.age + dtime
+		if time_to_live > 0 and self.age > time_to_live then
+			self.itemstring = ""
+			self.object:remove()
+			return
+		end
+
+		local pos = self.object:get_pos()
+		local node = core.get_node_or_nil({
+			x = pos.x,
+			y = pos.y + self._collisionbox[2] - 0.05,
+			z = pos.z
+		})
+		-- Delete in 'ignore' nodes
+		if node and node.name == "ignore" then
+			self.itemstring = ""
+			self.object:remove()
+			return
+		end
+
+		if self.force_out then
+			-- This code runs after the entity got a push from the is_stuck code.
+			-- It makes sure the entity is entirely outside the solid node
+			local c = self._collisionbox
+			local s = self.force_out_start
+			local f = self.force_out
+			local ok = (f.x > 0 and pos.x + c[1] > s.x + 0.5) or
+				(f.y > 0 and pos.y + c[2] > s.y + 0.5) or
+				(f.z > 0 and pos.z + c[3] > s.z + 0.5) or
+				(f.x < 0 and pos.x + c[4] < s.x - 0.5) or
+				(f.z < 0 and pos.z + c[6] < s.z - 0.5)
+			if ok then
+				-- Item was successfully forced out
+				self.force_out = nil
+				self:enable_physics()
+				return
+			end
+		end
+
+		if not self.physical_state then
+			return -- Don't do anything
+		end
+
+		assert(moveresult,
+			"Collision info missing, this is caused by an out-of-date/buggy mod or game")
+
+		if not moveresult.collides then
+			-- future TODO: items should probably decelerate in air
+			return
+		end
+
+		-- Push item out when stuck inside solid node
+		local is_stuck = false
+		local snode = core.get_node_or_nil(pos)
+		if snode then
+			local sdef = core.registered_nodes[snode.name] or {}
+			is_stuck = (sdef.walkable == nil or sdef.walkable == true)
+				and (sdef.collision_box == nil or sdef.collision_box.type == "regular")
+				and (sdef.node_box == nil or sdef.node_box.type == "regular")
+		end
+
+		if is_stuck then
+			local shootdir
+			local order = {
+				{x=1, y=0, z=0}, {x=-1, y=0, z= 0},
+				{x=0, y=0, z=1}, {x= 0, y=0, z=-1},
+			}
+
+			-- Check which one of the 4 sides is free
+			for o = 1, #order do
+				local cnode = core.get_node(vector.add(pos, order[o])).name
+				local cdef = core.registered_nodes[cnode] or {}
+				if cnode ~= "ignore" and cdef.walkable == false then
+					shootdir = order[o]
+					break
+				end
+			end
+			-- If none of the 4 sides is free, check upwards
+			if not shootdir then
+				shootdir = {x=0, y=1, z=0}
+				local cnode = core.get_node(vector.add(pos, shootdir)).name
+				if cnode == "ignore" then
+					shootdir = nil -- Do not push into ignore
+				end
+			end
+
+			if shootdir then
+				-- Set new item moving speed accordingly
+				local newv = vector.multiply(shootdir, 3)
+				self:disable_physics()
+				self.object:set_velocity(newv)
+
+				self.force_out = newv
+				self.force_out_start = vector.round(pos)
+				return
+			end
+		end
+
+		node = nil -- ground node we're colliding with
+		if moveresult.touching_ground then
+			for _, info in ipairs(moveresult.collisions) do
+				if info.axis == "y" then
+					node = core.get_node(info.node_pos)
+					break
+				end
+			end
+		end
+
+		-- Slide on slippery nodes
+		local def = node and core.registered_nodes[node.name]
+		local keep_movement = false
+
+		if def then
+			local slippery = core.get_item_group(node.name, "slippery")
+			local vel = self.object:get_velocity()
+			if slippery ~= 0 and (math.abs(vel.x) > 0.1 or math.abs(vel.z) > 0.1) then
+				-- Horizontal deceleration
+				local factor = math.min(4 / (slippery + 4) * dtime, 1)
+				self.object:set_velocity({
+					x = vel.x * (1 - factor),
+					y = 0,
+					z = vel.z * (1 - factor)
+				})
+				keep_movement = true
+			end
+		end
+
+		if not keep_movement then
+			self.object:set_velocity({x=0, y=0, z=0})
+		end
+
+		if self.moving_state == keep_movement then
+			-- Do not update anything until the moving state changes
+			return
+		end
+		self.moving_state = keep_movement
+
+		-- Only collect items if not moving
+		if self.moving_state then
+			return
+		end
+		-- Collect the items around to merge with
+		local own_stack = ItemStack(self.itemstring)
+		if own_stack:get_free_space() == 0 then
+			return
+		end
+		local objects = core.get_objects_inside_radius(pos, 1.0)
+		for k, obj in pairs(objects) do
+			local entity = obj:get_luaentity()
+			if entity and entity.name == "__builtin:item" then
+				if self:try_merge_with(own_stack, obj, entity) then
+					own_stack = ItemStack(self.itemstring)
+					if own_stack:get_free_space() == 0 then
+						return
+					end
+				end
+			end
+		end
+	end,
+
+	on_punch = function(self, hitter)
+		local inv = hitter:get_inventory()
+		if inv and self.itemstring ~= "" then
+			local left = inv:add_item("main", self.itemstring)
+			if left and not left:is_empty() then
+				self:set_item(left)
+				return
+			end
+		end
+		self.itemstring = ""
+		self.object:remove()
+	end,
+})

builtin/game/item_s.lua

@@ -0,0 +1,156 @@
+-- Minetest: builtin/item_s.lua
+-- The distinction of what goes here is a bit tricky, basically it's everything
+-- that does not (directly or indirectly) need access to ServerEnvironment,
+-- Server or writable access to IGameDef on the engine side.
+-- (The '_s' stands for standalone.)
+
+--
+-- Item definition helpers
+--
+
+function core.inventorycube(img1, img2, img3)
+	img2 = img2 or img1
+	img3 = img3 or img1
+	return "[inventorycube"
+			.. "{" .. img1:gsub("%^", "&")
+			.. "{" .. img2:gsub("%^", "&")
+			.. "{" .. img3:gsub("%^", "&")
+end
+
+function core.dir_to_facedir(dir, is6d)
+	--account for y if requested
+	if is6d and math.abs(dir.y) > math.abs(dir.x) and math.abs(dir.y) > math.abs(dir.z) then
+
+		--from above
+		if dir.y < 0 then
+			if math.abs(dir.x) > math.abs(dir.z) then
+				if dir.x < 0 then
+					return 19
+				else
+					return 13
+				end
+			else
+				if dir.z < 0 then
+					return 10
+				else
+					return 4
+				end
+			end
+
+		--from below
+		else
+			if math.abs(dir.x) > math.abs(dir.z) then
+				if dir.x < 0 then
+					return 15
+				else
+					return 17
+				end
+			else
+				if dir.z < 0 then
+					return 6
+				else
+					return 8
+				end
+			end
+		end
+
+	--otherwise, place horizontally
+	elseif math.abs(dir.x) > math.abs(dir.z) then
+		if dir.x < 0 then
+			return 3
+		else
+			return 1
+		end
+	else
+		if dir.z < 0 then
+			return 2
+		else
+			return 0
+		end
+	end
+end
+
+-- Table of possible dirs
+local facedir_to_dir = {
+	vector.new( 0,  0,  1),
+	vector.new( 1,  0,  0),
+	vector.new( 0,  0, -1),
+	vector.new(-1,  0,  0),
+	vector.new( 0, -1,  0),
+	vector.new( 0,  1,  0),
+}
+-- Mapping from facedir value to index in facedir_to_dir.
+local facedir_to_dir_map = {
+	[0]=1, 2, 3, 4,
+	5, 2, 6, 4,
+	6, 2, 5, 4,
+	1, 5, 3, 6,
+	1, 6, 3, 5,
+	1, 4, 3, 2,
+}
+function core.facedir_to_dir(facedir)
+	return facedir_to_dir[facedir_to_dir_map[facedir % 32]]
+end
+
+function core.dir_to_wallmounted(dir)
+	if math.abs(dir.y) > math.max(math.abs(dir.x), math.abs(dir.z)) then
+		if dir.y < 0 then
+			return 1
+		else
+			return 0
+		end
+	elseif math.abs(dir.x) > math.abs(dir.z) then
+		if dir.x < 0 then
+			return 3
+		else
+			return 2
+		end
+	else
+		if dir.z < 0 then
+			return 5
+		else
+			return 4
+		end
+	end
+end
+
+-- table of dirs in wallmounted order
+local wallmounted_to_dir = {
+	[0] = vector.new( 0,  1,  0),
+	vector.new( 0, -1,  0),
+	vector.new( 1,  0,  0),
+	vector.new(-1,  0,  0),
+	vector.new( 0,  0,  1),
+	vector.new( 0,  0, -1),
+}
+function core.wallmounted_to_dir(wallmounted)
+	return wallmounted_to_dir[wallmounted % 8]
+end
+
+function core.dir_to_yaw(dir)
+	return -math.atan2(dir.x, dir.z)
+end
+
+function core.yaw_to_dir(yaw)
+	return vector.new(-math.sin(yaw), 0, math.cos(yaw))
+end
+
+function core.is_colored_paramtype(ptype)
+	return (ptype == "color") or (ptype == "colorfacedir") or
+		(ptype == "colorwallmounted") or (ptype == "colordegrotate")
+end
+
+function core.strip_param2_color(param2, paramtype2)
+	if not core.is_colored_paramtype(paramtype2) then
+		return nil
+	end
+	if paramtype2 == "colorfacedir" then
+		param2 = math.floor(param2 / 32) * 32
+	elseif paramtype2 == "colorwallmounted" then
+		param2 = math.floor(param2 / 8) * 8
+	elseif paramtype2 == "colordegrotate" then
+		param2 = math.floor(param2 / 32) * 32
+	end
+	-- paramtype2 == "color" requires no modification.
+	return param2
+end

builtin/game/knockback.lua

@@ -0,0 +1,46 @@
+-- can be overriden by mods
+function core.calculate_knockback(player, hitter, time_from_last_punch, tool_capabilities, dir, distance, damage)
+	if damage == 0 or player:get_armor_groups().immortal then
+		return 0.0
+	end
+
+	local m = 8
+	-- solve m - m*e^(k*4) = 4 for k
+	local k = -0.17328
+	local res = m - m * math.exp(k * damage)
+
+	if distance < 2.0 then
+		res = res * 1.1 -- more knockback when closer
+	elseif distance > 4.0 then
+		res = res * 0.9 -- less when far away
+	end
+	return res
+end
+
+local function vector_absmax(v)
+	local max, abs = math.max, math.abs
+	return max(max(abs(v.x), abs(v.y)), abs(v.z))
+end
+
+core.register_on_punchplayer(function(player, hitter, time_from_last_punch, tool_capabilities, unused_dir, damage)
+	if player:get_hp() == 0 then
+		return -- RIP
+	end
+
+	-- Server::handleCommand_Interact() adds eye offset to one but not the other
+	-- so the direction is slightly off, calculate it ourselves
+	local dir = vector.subtract(player:get_pos(), hitter:get_pos())
+	local d = vector.length(dir)
+	if d ~= 0.0 then
+		dir = vector.divide(dir, d)
+	end
+
+	local k = core.calculate_knockback(player, hitter, time_from_last_punch, tool_capabilities, dir, d, damage)
+
+	local kdir = vector.multiply(dir, k)
+	if vector_absmax(kdir) < 1.0 then
+		return -- barely noticeable, so don't even send
+	end
+
+	player:add_velocity(kdir)
+end)

builtin/game/misc.lua

@@ -0,0 +1,266 @@
+-- Minetest: builtin/misc.lua
+
+local S = core.get_translator("__builtin")
+
+--
+-- Misc. API functions
+--
+
+-- @spec core.kick_player(String, String) :: Boolean
+function core.kick_player(player_name, reason)
+	if type(reason) == "string" then
+		reason = "Kicked: " .. reason
+	else
+		reason = "Kicked."
+	end
+	return core.disconnect_player(player_name, reason)
+end
+
+function core.check_player_privs(name, ...)
+	if core.is_player(name) then
+		name = name:get_player_name()
+	elseif type(name) ~= "string" then
+		error("core.check_player_privs expects a player or playername as " ..
+			"argument.", 2)
+	end
+
+	local requested_privs = {...}
+	local player_privs = core.get_player_privs(name)
+	local missing_privileges = {}
+
+	if type(requested_privs[1]) == "table" then
+		-- We were provided with a table like { privA = true, privB = true }.
+		for priv, value in pairs(requested_privs[1]) do
+			if value and not player_privs[priv] then
+				missing_privileges[#missing_privileges + 1] = priv
+			end
+		end
+	else
+		-- Only a list, we can process it directly.
+		for key, priv in pairs(requested_privs) do
+			if not player_privs[priv] then
+				missing_privileges[#missing_privileges + 1] = priv
+			end
+		end
+	end
+
+	if #missing_privileges > 0 then
+		return false, missing_privileges
+	end
+
+	return true, ""
+end
+
+
+function core.send_join_message(player_name)
+	if not core.is_singleplayer() then
+		core.chat_send_all("*** " .. S("@1 joined the game.", player_name))
+	end
+end
+
+
+function core.send_leave_message(player_name, timed_out)
+	local announcement = "*** " .. S("@1 left the game.", player_name)
+	if timed_out then
+		announcement = "*** " .. S("@1 left the game (timed out).", player_name)
+	end
+	core.chat_send_all(announcement)
+end
+
+
+core.register_on_joinplayer(function(player)
+	local player_name = player:get_player_name()
+	if not core.is_singleplayer() then
+		local status = core.get_server_status(player_name, true)
+		if status and status ~= "" then
+			core.chat_send_player(player_name, status)
+		end
+	end
+	core.send_join_message(player_name)
+end)
+
+
+core.register_on_leaveplayer(function(player, timed_out)
+	local player_name = player:get_player_name()
+	core.send_leave_message(player_name, timed_out)
+end)
+
+
+function core.is_player(player)
+	-- a table being a player is also supported because it quacks sufficiently
+	-- like a player if it has the is_player function
+	local t = type(player)
+	return (t == "userdata" or t == "table") and
+		type(player.is_player) == "function" and player:is_player()
+end
+
+
+function core.player_exists(name)
+	return core.get_auth_handler().get_auth(name) ~= nil
+end
+
+
+-- Returns two position vectors representing a box of `radius` in each
+-- direction centered around the player corresponding to `player_name`
+
+function core.get_player_radius_area(player_name, radius)
+	local player = core.get_player_by_name(player_name)
+	if player == nil then
+		return nil
+	end
+
+	local p1 = player:get_pos()
+	local p2 = p1
+
+	if radius then
+		p1 = vector.subtract(p1, radius)
+		p2 = vector.add(p2, radius)
+	end
+
+	return p1, p2
+end
+
+
+-- To be overriden by protection mods
+
+function core.is_protected(pos, name)
+	return false
+end
+
+
+function core.record_protection_violation(pos, name)
+	for _, func in pairs(core.registered_on_protection_violation) do
+		func(pos, name)
+	end
+end
+
+-- To be overridden by Creative mods
+
+local creative_mode_cache = core.settings:get_bool("creative_mode")
+function core.is_creative_enabled(name)
+	return creative_mode_cache
+end
+
+-- Checks if specified volume intersects a protected volume
+
+function core.is_area_protected(minp, maxp, player_name, interval)
+	-- 'interval' is the largest allowed interval for the 3D lattice of checks.
+
+	-- Compute the optimal float step 'd' for each axis so that all corners and
+	-- borders are checked. 'd' will be smaller or equal to 'interval'.
+	-- Subtracting 1e-4 ensures that the max co-ordinate will be reached by the
+	-- for loop (which might otherwise not be the case due to rounding errors).
+
+	-- Default to 4
+	interval = interval or 4
+	local d = {}
+
+	for _, c in pairs({"x", "y", "z"}) do
+		if minp[c] > maxp[c] then
+			-- Repair positions: 'minp' > 'maxp'
+			local tmp = maxp[c]
+			maxp[c] = minp[c]
+			minp[c] = tmp
+		end
+
+		if maxp[c] > minp[c] then
+			d[c] = (maxp[c] - minp[c]) /
+				math.ceil((maxp[c] - minp[c]) / interval) - 1e-4
+		else
+			d[c] = 1 -- Any value larger than 0 to avoid division by zero
+		end
+	end
+
+	for zf = minp.z, maxp.z, d.z do
+		local z = math.floor(zf + 0.5)
+		for yf = minp.y, maxp.y, d.y do
+			local y = math.floor(yf + 0.5)
+			for xf = minp.x, maxp.x, d.x do
+				local x = math.floor(xf + 0.5)
+				local pos = vector.new(x, y, z)
+				if core.is_protected(pos, player_name) then
+					return pos
+				end
+			end
+		end
+	end
+	return false
+end
+
+
+local raillike_ids = {}
+local raillike_cur_id = 0
+function core.raillike_group(name)
+	local id = raillike_ids[name]
+	if not id then
+		raillike_cur_id = raillike_cur_id + 1
+		raillike_ids[name] = raillike_cur_id
+		id = raillike_cur_id
+	end
+	return id
+end
+
+
+-- HTTP callback interface
+
+core.set_http_api_lua(function(httpenv)
+	httpenv.fetch = function(req, callback)
+		local handle = httpenv.fetch_async(req)
+
+		local function update_http_status()
+			local res = httpenv.fetch_async_get(handle)
+			if res.completed then
+				callback(res)
+			else
+				core.after(0, update_http_status)
+			end
+		end
+		core.after(0, update_http_status)
+	end
+
+	return httpenv
+end)
+core.set_http_api_lua = nil
+
+
+function core.close_formspec(player_name, formname)
+	return core.show_formspec(player_name, formname, "")
+end
+
+
+function core.cancel_shutdown_requests()
+	core.request_shutdown("", false, -1)
+end
+
+
+-- Used for callback handling with dynamic_add_media
+core.dynamic_media_callbacks = {}
+
+
+-- Transfer of certain globals into async environment
+-- see builtin/async/game.lua for the other side
+
+local function copy_filtering(t, seen)
+	if type(t) == "userdata" or type(t) == "function" then
+		return true -- don't use nil so presence can still be detected
+	elseif type(t) ~= "table" then
+		return t
+	end
+	local n = {}
+	seen = seen or {}
+	seen[t] = n
+	for k, v in pairs(t) do
+		local k_ = seen[k] or copy_filtering(k, seen)
+		local v_ = seen[v] or copy_filtering(v, seen)
+		n[k_] = v_
+	end
+	return n
+end
+
+function core.get_globals_to_transfer()
+	local all = {
+		registered_items = copy_filtering(core.registered_items),
+		registered_aliases = core.registered_aliases,
+	}
+	return all
+end

builtin/game/misc_s.lua

@@ -0,0 +1,93 @@
+-- Minetest: builtin/misc_s.lua
+-- The distinction of what goes here is a bit tricky, basically it's everything
+-- that does not (directly or indirectly) need access to ServerEnvironment,
+-- Server or writable access to IGameDef on the engine side.
+-- (The '_s' stands for standalone.)
+
+--
+-- Misc. API functions
+--
+
+function core.hash_node_position(pos)
+	return (pos.z + 32768) * 65536 * 65536
+		 + (pos.y + 32768) * 65536
+		 +  pos.x + 32768
+end
+
+
+function core.get_position_from_hash(hash)
+	local x = (hash % 65536) - 32768
+	hash  = math.floor(hash / 65536)
+	local y = (hash % 65536) - 32768
+	hash  = math.floor(hash / 65536)
+	local z = (hash % 65536) - 32768
+	return vector.new(x, y, z)
+end
+
+
+function core.get_item_group(name, group)
+	if not core.registered_items[name] or not
+			core.registered_items[name].groups[group] then
+		return 0
+	end
+	return core.registered_items[name].groups[group]
+end
+
+
+function core.get_node_group(name, group)
+	core.log("deprecated", "Deprecated usage of get_node_group, use get_item_group instead")
+	return core.get_item_group(name, group)
+end
+
+
+function core.setting_get_pos(name)
+	local value = core.settings:get(name)
+	if not value then
+		return nil
+	end
+	return core.string_to_pos(value)
+end
+
+
+-- See l_env.cpp for the other functions
+function core.get_artificial_light(param1)
+	return math.floor(param1 / 16)
+end
+
+-- PNG encoder safety wrapper
+
+local o_encode_png = core.encode_png
+function core.encode_png(width, height, data, compression)
+	if type(width) ~= "number" then
+		error("Incorrect type for 'width', expected number, got " .. type(width))
+	end
+	if type(height) ~= "number" then
+		error("Incorrect type for 'height', expected number, got " .. type(height))
+	end
+
+	local expected_byte_count = width * height * 4
+
+	if type(data) ~= "table" and type(data) ~= "string" then
+		error("Incorrect type for 'data', expected table or string, got " .. type(data))
+	end
+
+	local data_length = type(data) == "table" and #data * 4 or string.len(data)
+
+	if data_length ~= expected_byte_count then
+		error(string.format(
+			"Incorrect length of 'data', width and height imply %d bytes but %d were provided",
+			expected_byte_count,
+			data_length
+		))
+	end
+
+	if type(data) == "table" then
+		local dataBuf = {}
+		for i = 1, #data do
+			dataBuf[i] = core.colorspec_to_bytes(data[i])
+		end
+		data = table.concat(dataBuf)
+	end
+
+	return o_encode_png(width, height, data, compression or 6)
+end

builtin/game/privileges.lua

@@ -0,0 +1,108 @@
+-- Minetest: builtin/privileges.lua
+
+local S = core.get_translator("__builtin")
+
+--
+-- Privileges
+--
+
+core.registered_privileges = {}
+
+function core.register_privilege(name, param)
+	local function fill_defaults(def)
+		if def.give_to_singleplayer == nil then
+			def.give_to_singleplayer = true
+		end
+		if def.give_to_admin == nil then
+			def.give_to_admin = def.give_to_singleplayer
+		end
+		if def.description == nil then
+			def.description = S("(no description)")
+		end
+	end
+	local def
+	if type(param) == "table" then
+		def = param
+	else
+		def = {description = param}
+	end
+	fill_defaults(def)
+	core.registered_privileges[name] = def
+end
+
+core.register_privilege("interact", S("Can interact with things and modify the world"))
+core.register_privilege("shout", S("Can speak in chat"))
+
+local basic_privs =
+	core.string_to_privs((core.settings:get("basic_privs") or "shout,interact"))
+local basic_privs_desc = S("Can modify basic privileges (@1)",
+	core.privs_to_string(basic_privs, ', '))
+core.register_privilege("basic_privs", basic_privs_desc)
+
+core.register_privilege("privs", S("Can modify privileges"))
+
+core.register_privilege("teleport", {
+	description = S("Can teleport self"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("bring", {
+	description = S("Can teleport other players"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("settime", {
+	description = S("Can set the time of day using /time"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("server", {
+	description = S("Can do server maintenance stuff"),
+	give_to_singleplayer = false,
+	give_to_admin = true,
+})
+core.register_privilege("protection_bypass", {
+	description = S("Can bypass node protection in the world"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("ban", {
+	description = S("Can ban and unban players"),
+	give_to_singleplayer = false,
+	give_to_admin = true,
+})
+core.register_privilege("kick", {
+	description = S("Can kick players"),
+	give_to_singleplayer = false,
+	give_to_admin = true,
+})
+core.register_privilege("give", {
+	description = S("Can use /give and /giveme"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("password", {
+	description = S("Can use /setpassword and /clearpassword"),
+	give_to_singleplayer = false,
+	give_to_admin = true,
+})
+core.register_privilege("fly", {
+	description = S("Can use fly mode"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("fast", {
+	description = S("Can use fast mode"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("noclip", {
+	description = S("Can fly through solid nodes using noclip mode"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("rollback", {
+	description = S("Can use the rollback functionality"),
+	give_to_singleplayer = false,
+})
+core.register_privilege("debug", {
+	description = S("Can enable wireframe"),
+	give_to_singleplayer = false,
+})
+
+core.register_can_bypass_userlimit(function(name, ip)
+	local privs = core.get_player_privs(name)
+	return privs["server"] or privs["ban"] or privs["privs"] or privs["password"]
+end)

builtin/game/register.lua

@@ -0,0 +1,625 @@
+-- Minetest: builtin/register.lua
+
+local S = core.get_translator("__builtin")
+
+--
+-- Make raw registration functions inaccessible to anyone except this file
+--
+
+local register_item_raw = core.register_item_raw
+core.register_item_raw = nil
+
+local unregister_item_raw = core.unregister_item_raw
+core.unregister_item_raw = nil
+
+local register_alias_raw = core.register_alias_raw
+core.register_alias_raw = nil
+
+--
+-- Item / entity / ABM / LBM registration functions
+--
+
+core.registered_abms = {}
+core.registered_lbms = {}
+core.registered_entities = {}
+core.registered_items = {}
+core.registered_nodes = {}
+core.registered_craftitems = {}
+core.registered_tools = {}
+core.registered_aliases = {}
+
+-- For tables that are indexed by item name:
+-- If table[X] does not exist, default to table[core.registered_aliases[X]]
+local alias_metatable = {
+	__index = function(t, name)
+		return rawget(t, core.registered_aliases[name])
+	end
+}
+setmetatable(core.registered_items, alias_metatable)
+setmetatable(core.registered_nodes, alias_metatable)
+setmetatable(core.registered_craftitems, alias_metatable)
+setmetatable(core.registered_tools, alias_metatable)
+
+-- These item names may not be used because they would interfere
+-- with legacy itemstrings
+local forbidden_item_names = {
+	MaterialItem = true,
+	MaterialItem2 = true,
+	MaterialItem3 = true,
+	NodeItem = true,
+	node = true,
+	CraftItem = true,
+	craft = true,
+	MBOItem = true,
+	ToolItem = true,
+	tool = true,
+}
+
+local function check_modname_prefix(name)
+	if name:sub(1,1) == ":" then
+		-- If the name starts with a colon, we can skip the modname prefix
+		-- mechanism.
+		return name:sub(2)
+	else
+		-- Enforce that the name starts with the correct mod name.
+		local expected_prefix = core.get_current_modname() .. ":"
+		if name:sub(1, #expected_prefix) ~= expected_prefix then
+			error("Name " .. name .. " does not follow naming conventions: " ..
+				"\"" .. expected_prefix .. "\" or \":\" prefix required")
+		end
+
+		-- Enforce that the name only contains letters, numbers and underscores.
+		local subname = name:sub(#expected_prefix+1)
+		if subname:find("[^%w_]") then
+			error("Name " .. name .. " does not follow naming conventions: " ..
+				"contains unallowed characters")
+		end
+
+		return name
+	end
+end
+
+function core.register_abm(spec)
+	-- Add to core.registered_abms
+	assert(type(spec.action) == "function", "Required field 'action' of type function")
+	core.registered_abms[#core.registered_abms + 1] = spec
+	spec.mod_origin = core.get_current_modname() or "??"
+end
+
+function core.register_lbm(spec)
+	-- Add to core.registered_lbms
+	check_modname_prefix(spec.name)
+	assert(type(spec.action) == "function", "Required field 'action' of type function")
+	core.registered_lbms[#core.registered_lbms + 1] = spec
+	spec.mod_origin = core.get_current_modname() or "??"
+end
+
+function core.register_entity(name, prototype)
+	-- Check name
+	if name == nil then
+		error("Unable to register entity: Name is nil")
+	end
+	name = check_modname_prefix(tostring(name))
+
+	prototype.name = name
+	prototype.__index = prototype  -- so that it can be used as a metatable
+
+	-- Add to core.registered_entities
+	core.registered_entities[name] = prototype
+	prototype.mod_origin = core.get_current_modname() or "??"
+end
+
+function core.register_item(name, itemdef)
+	-- Check name
+	if name == nil then
+		error("Unable to register item: Name is nil")
+	end
+	name = check_modname_prefix(tostring(name))
+	if forbidden_item_names[name] then
+		error("Unable to register item: Name is forbidden: " .. name)
+	end
+	itemdef.name = name
+
+	-- Apply defaults and add to registered_* table
+	if itemdef.type == "node" then
+		-- Use the nodebox as selection box if it's not set manually
+		if itemdef.drawtype == "nodebox" and not itemdef.selection_box then
+			itemdef.selection_box = itemdef.node_box
+		elseif itemdef.drawtype == "fencelike" and not itemdef.selection_box then
+			itemdef.selection_box = {
+				type = "fixed",
+				fixed = {-1/8, -1/2, -1/8, 1/8, 1/2, 1/8},
+			}
+		end
+		if itemdef.light_source and itemdef.light_source > core.LIGHT_MAX then
+			itemdef.light_source = core.LIGHT_MAX
+			core.log("warning", "Node 'light_source' value exceeds maximum," ..
+				" limiting to maximum: " ..name)
+		end
+		setmetatable(itemdef, {__index = core.nodedef_default})
+		core.registered_nodes[itemdef.name] = itemdef
+	elseif itemdef.type == "craft" then
+		setmetatable(itemdef, {__index = core.craftitemdef_default})
+		core.registered_craftitems[itemdef.name] = itemdef
+	elseif itemdef.type == "tool" then
+		setmetatable(itemdef, {__index = core.tooldef_default})
+		core.registered_tools[itemdef.name] = itemdef
+	elseif itemdef.type == "none" then
+		setmetatable(itemdef, {__index = core.noneitemdef_default})
+	else
+		error("Unable to register item: Type is invalid: " .. dump(itemdef))
+	end
+
+	-- Flowing liquid uses param2
+	if itemdef.type == "node" and itemdef.liquidtype == "flowing" then
+		itemdef.paramtype2 = "flowingliquid"
+	end
+
+	-- BEGIN Legacy stuff
+	if itemdef.cookresult_itemstring ~= nil and itemdef.cookresult_itemstring ~= "" then
+		core.register_craft({
+			type="cooking",
+			output=itemdef.cookresult_itemstring,
+			recipe=itemdef.name,
+			cooktime=itemdef.furnace_cooktime
+		})
+	end
+	if itemdef.furnace_burntime ~= nil and itemdef.furnace_burntime >= 0 then
+		core.register_craft({
+			type="fuel",
+			recipe=itemdef.name,
+			burntime=itemdef.furnace_burntime
+		})
+	end
+	-- END Legacy stuff
+
+	itemdef.mod_origin = core.get_current_modname() or "??"
+
+	-- Disable all further modifications
+	getmetatable(itemdef).__newindex = {}
+
+	--core.log("Registering item: " .. itemdef.name)
+	core.registered_items[itemdef.name] = itemdef
+	core.registered_aliases[itemdef.name] = nil
+	register_item_raw(itemdef)
+end
+
+function core.unregister_item(name)
+	if not core.registered_items[name] then
+		core.log("warning", "Not unregistering item " ..name..
+			" because it doesn't exist.")
+		return
+	end
+	-- Erase from registered_* table
+	local type = core.registered_items[name].type
+	if type == "node" then
+		core.registered_nodes[name] = nil
+	elseif type == "craft" then
+		core.registered_craftitems[name] = nil
+	elseif type == "tool" then
+		core.registered_tools[name] = nil
+	end
+	core.registered_items[name] = nil
+
+
+	unregister_item_raw(name)
+end
+
+function core.register_node(name, nodedef)
+	nodedef.type = "node"
+	core.register_item(name, nodedef)
+end
+
+function core.register_craftitem(name, craftitemdef)
+	craftitemdef.type = "craft"
+
+	-- BEGIN Legacy stuff
+	if craftitemdef.inventory_image == nil and craftitemdef.image ~= nil then
+		craftitemdef.inventory_image = craftitemdef.image
+	end
+	-- END Legacy stuff
+
+	core.register_item(name, craftitemdef)
+end
+
+function core.register_tool(name, tooldef)
+	tooldef.type = "tool"
+	tooldef.stack_max = 1
+
+	-- BEGIN Legacy stuff
+	if tooldef.inventory_image == nil and tooldef.image ~= nil then
+		tooldef.inventory_image = tooldef.image
+	end
+	if tooldef.tool_capabilities == nil and
+	   (tooldef.full_punch_interval ~= nil or
+	    tooldef.basetime ~= nil or
+	    tooldef.dt_weight ~= nil or
+	    tooldef.dt_crackiness ~= nil or
+	    tooldef.dt_crumbliness ~= nil or
+	    tooldef.dt_cuttability ~= nil or
+	    tooldef.basedurability ~= nil or
+	    tooldef.dd_weight ~= nil or
+	    tooldef.dd_crackiness ~= nil or
+	    tooldef.dd_crumbliness ~= nil or
+	    tooldef.dd_cuttability ~= nil) then
+		tooldef.tool_capabilities = {
+			full_punch_interval = tooldef.full_punch_interval,
+			basetime = tooldef.basetime,
+			dt_weight = tooldef.dt_weight,
+			dt_crackiness = tooldef.dt_crackiness,
+			dt_crumbliness = tooldef.dt_crumbliness,
+			dt_cuttability = tooldef.dt_cuttability,
+			basedurability = tooldef.basedurability,
+			dd_weight = tooldef.dd_weight,
+			dd_crackiness = tooldef.dd_crackiness,
+			dd_crumbliness = tooldef.dd_crumbliness,
+			dd_cuttability = tooldef.dd_cuttability,
+		}
+	end
+	-- END Legacy stuff
+
+	-- This isn't just legacy, but more of a convenience feature
+	local toolcaps = tooldef.tool_capabilities
+	if toolcaps and toolcaps.punch_attack_uses == nil then
+		for _, cap in pairs(toolcaps.groupcaps or {}) do
+			local level = (cap.maxlevel or 0) - 1
+			if (cap.uses or 0) ~= 0 and level >= 0 then
+				toolcaps.punch_attack_uses = cap.uses * (3 ^ level)
+				break
+			end
+		end
+	end
+
+	core.register_item(name, tooldef)
+end
+
+function core.register_alias(name, convert_to)
+	if forbidden_item_names[name] then
+		error("Unable to register alias: Name is forbidden: " .. name)
+	end
+	if core.registered_items[name] ~= nil then
+		core.log("warning", "Not registering alias, item with same name" ..
+			" is already defined: " .. name .. " -> " .. convert_to)
+	else
+		--core.log("Registering alias: " .. name .. " -> " .. convert_to)
+		core.registered_aliases[name] = convert_to
+		register_alias_raw(name, convert_to)
+	end
+end
+
+function core.register_alias_force(name, convert_to)
+	if forbidden_item_names[name] then
+		error("Unable to register alias: Name is forbidden: " .. name)
+	end
+	if core.registered_items[name] ~= nil then
+		core.unregister_item(name)
+		core.log("info", "Removed item " ..name..
+			" while attempting to force add an alias")
+	end
+	--core.log("Registering alias: " .. name .. " -> " .. convert_to)
+	core.registered_aliases[name] = convert_to
+	register_alias_raw(name, convert_to)
+end
+
+function core.on_craft(itemstack, player, old_craft_list, craft_inv)
+	for _, func in ipairs(core.registered_on_crafts) do
+		-- cast to ItemStack since func() could return a string
+		itemstack = ItemStack(func(itemstack, player, old_craft_list, craft_inv) or itemstack)
+	end
+	return itemstack
+end
+
+function core.craft_predict(itemstack, player, old_craft_list, craft_inv)
+	for _, func in ipairs(core.registered_craft_predicts) do
+		-- cast to ItemStack since func() could return a string
+		itemstack = ItemStack(func(itemstack, player, old_craft_list, craft_inv) or itemstack)
+	end
+	return itemstack
+end
+
+-- Alias the forbidden item names to "" so they can't be
+-- created via itemstrings (e.g. /give)
+for name in pairs(forbidden_item_names) do
+	core.registered_aliases[name] = ""
+	register_alias_raw(name, "")
+end
+
+--
+-- Built-in node definitions. Also defined in C.
+--
+
+core.register_item(":unknown", {
+	type = "none",
+	description = S("Unknown Item"),
+	inventory_image = "unknown_item.png",
+	on_place = core.item_place,
+	on_secondary_use = core.item_secondary_use,
+	on_drop = core.item_drop,
+	groups = {not_in_creative_inventory=1},
+	diggable = true,
+})
+
+core.register_node(":air", {
+	description = S("Air"),
+	inventory_image = "air.png",
+	wield_image = "air.png",
+	drawtype = "airlike",
+	paramtype = "light",
+	sunlight_propagates = true,
+	walkable = false,
+	pointable = false,
+	diggable = false,
+	buildable_to = true,
+	floodable = true,
+	air_equivalent = true,
+	drop = "",
+	groups = {not_in_creative_inventory=1},
+})
+
+core.register_node(":ignore", {
+	description = S("Ignore"),
+	inventory_image = "ignore.png",
+	wield_image = "ignore.png",
+	drawtype = "airlike",
+	paramtype = "none",
+	sunlight_propagates = false,
+	walkable = false,
+	pointable = false,
+	diggable = false,
+	buildable_to = true, -- A way to remove accidentally placed ignores
+	air_equivalent = true,
+	drop = "",
+	groups = {not_in_creative_inventory=1},
+	node_placement_prediction = "",
+	on_place = function(itemstack, placer, pointed_thing)
+		core.chat_send_player(
+				placer:get_player_name(),
+				core.colorize("#FF0000",
+				S("You can't place 'ignore' nodes!")))
+		return ""
+	end,
+})
+
+-- The hand (bare definition)
+core.register_item(":", {
+	type = "none",
+	wield_image = "wieldhand.png",
+	groups = {not_in_creative_inventory=1},
+})
+
+
+function core.override_item(name, redefinition)
+	if redefinition.name ~= nil then
+		error("Attempt to redefine name of "..name.." to "..dump(redefinition.name), 2)
+	end
+	if redefinition.type ~= nil then
+		error("Attempt to redefine type of "..name.." to "..dump(redefinition.type), 2)
+	end
+	local item = core.registered_items[name]
+	if not item then
+		error("Attempt to override non-existent item "..name, 2)
+	end
+	for k, v in pairs(redefinition) do
+		rawset(item, k, v)
+	end
+	register_item_raw(item)
+end
+
+do
+	local default = {mod = "??", name = "??"}
+	core.callback_origins = setmetatable({}, {
+		__index = function()
+			return default
+		end
+	})
+end
+
+function core.run_callbacks(callbacks, mode, ...)
+	assert(type(callbacks) == "table")
+	local cb_len = #callbacks
+	if cb_len == 0 then
+		if mode == 2 or mode == 3 then
+			return true
+		elseif mode == 4 or mode == 5 then
+			return false
+		end
+	end
+	local ret = nil
+	for i = 1, cb_len do
+		local origin = core.callback_origins[callbacks[i]]
+		core.set_last_run_mod(origin.mod)
+		local cb_ret = callbacks[i](...)
+
+		if mode == 0 and i == 1 then
+			ret = cb_ret
+		elseif mode == 1 and i == cb_len then
+			ret = cb_ret
+		elseif mode == 2 then
+			if not cb_ret or i == 1 then
+				ret = cb_ret
+			end
+		elseif mode == 3 then
+			if cb_ret then
+				return cb_ret
+			end
+			ret = cb_ret
+		elseif mode == 4 then
+			if (cb_ret and not ret) or i == 1 then
+				ret = cb_ret
+			end
+		elseif mode == 5 and cb_ret then
+			return cb_ret
+		end
+	end
+	return ret
+end
+
+function core.run_priv_callbacks(name, priv, caller, method)
+	local def = core.registered_privileges[priv]
+	if not def or not def["on_" .. method] or
+			not def["on_" .. method](name, caller) then
+		for _, func in ipairs(core["registered_on_priv_" .. method]) do
+			if not func(name, caller, priv) then
+				break
+			end
+		end
+	end
+end
+
+--
+-- Callback registration
+--
+
+local function make_registration()
+	local t = {}
+	local registerfunc = function(func)
+		t[#t + 1] = func
+		core.callback_origins[func] = {
+			mod = core.get_current_modname() or "??",
+			name = debug.getinfo(1, "n").name or "??"
+		}
+		--local origin = core.callback_origins[func]
+		--print(origin.name .. ": " .. origin.mod .. " registering cbk " .. tostring(func))
+	end
+	return t, registerfunc
+end
+
+local function make_registration_reverse()
+	local t = {}
+	local registerfunc = function(func)
+		table.insert(t, 1, func)
+		core.callback_origins[func] = {
+			mod = core.get_current_modname() or "??",
+			name = debug.getinfo(1, "n").name or "??"
+		}
+		--local origin = core.callback_origins[func]
+		--print(origin.name .. ": " .. origin.mod .. " registering cbk " .. tostring(func))
+	end
+	return t, registerfunc
+end
+
+local function make_registration_wrap(reg_fn_name, clear_fn_name)
+	local list = {}
+
+	local orig_reg_fn = core[reg_fn_name]
+	core[reg_fn_name] = function(def)
+		local retval = orig_reg_fn(def)
+		if retval ~= nil then
+			if def.name ~= nil then
+				list[def.name] = def
+			else
+				list[retval] = def
+			end
+		end
+		return retval
+	end
+
+	local orig_clear_fn = core[clear_fn_name]
+	core[clear_fn_name] = function()
+		for k in pairs(list) do
+			list[k] = nil
+		end
+		return orig_clear_fn()
+	end
+
+	return list
+end
+
+local function make_wrap_deregistration(reg_fn, clear_fn, list)
+	local unregister = function (key)
+		if type(key) ~= "string" then
+			error("key is not a string", 2)
+		end
+		if not list[key] then
+			error("Attempt to unregister non-existent element - '" .. key .. "'", 2)
+		end
+		local temporary_list = table.copy(list)
+		clear_fn()
+		for k,v in pairs(temporary_list) do
+			if key ~= k then
+				reg_fn(v)
+			end
+		end
+	end
+	return unregister
+end
+
+core.registered_on_player_hpchanges = { modifiers = { }, loggers = { } }
+
+function core.registered_on_player_hpchange(player, hp_change, reason)
+	local last
+	for i = #core.registered_on_player_hpchanges.modifiers, 1, -1 do
+		local func = core.registered_on_player_hpchanges.modifiers[i]
+		hp_change, last = func(player, hp_change, reason)
+		if type(hp_change) ~= "number" then
+			local debuginfo = debug.getinfo(func)
+			error("The register_on_hp_changes function has to return a number at " ..
+				debuginfo.short_src .. " line " .. debuginfo.linedefined)
+		end
+		if last then
+			break
+		end
+	end
+	for i, func in ipairs(core.registered_on_player_hpchanges.loggers) do
+		func(player, hp_change, reason)
+	end
+	return hp_change
+end
+
+function core.register_on_player_hpchange(func, modifier)
+	if modifier then
+		core.registered_on_player_hpchanges.modifiers[#core.registered_on_player_hpchanges.modifiers + 1] = func
+	else
+		core.registered_on_player_hpchanges.loggers[#core.registered_on_player_hpchanges.loggers + 1] = func
+	end
+	core.callback_origins[func] = {
+		mod = core.get_current_modname() or "??",
+		name = debug.getinfo(1, "n").name or "??"
+	}
+end
+
+core.registered_biomes      = make_registration_wrap("register_biome",      "clear_registered_biomes")
+core.registered_ores        = make_registration_wrap("register_ore",        "clear_registered_ores")
+core.registered_decorations = make_registration_wrap("register_decoration", "clear_registered_decorations")
+
+core.unregister_biome = make_wrap_deregistration(core.register_biome,
+		core.clear_registered_biomes, core.registered_biomes)
+
+core.registered_on_chat_messages, core.register_on_chat_message = make_registration()
+core.registered_on_chatcommands, core.register_on_chatcommand = make_registration()
+core.registered_globalsteps, core.register_globalstep = make_registration()
+core.registered_playerevents, core.register_playerevent = make_registration()
+core.registered_on_mods_loaded, core.register_on_mods_loaded = make_registration()
+core.registered_on_shutdown, core.register_on_shutdown = make_registration()
+core.registered_on_punchnodes, core.register_on_punchnode = make_registration()
+core.registered_on_placenodes, core.register_on_placenode = make_registration()
+core.registered_on_dignodes, core.register_on_dignode = make_registration()
+core.registered_on_generateds, core.register_on_generated = make_registration()
+core.registered_on_newplayers, core.register_on_newplayer = make_registration()
+core.registered_on_dieplayers, core.register_on_dieplayer = make_registration()
+core.registered_on_respawnplayers, core.register_on_respawnplayer = make_registration()
+core.registered_on_prejoinplayers, core.register_on_prejoinplayer = make_registration()
+core.registered_on_joinplayers, core.register_on_joinplayer = make_registration()
+core.registered_on_leaveplayers, core.register_on_leaveplayer = make_registration()
+core.registered_on_player_receive_fields, core.register_on_player_receive_fields = make_registration_reverse()
+core.registered_on_cheats, core.register_on_cheat = make_registration()
+core.registered_on_crafts, core.register_on_craft = make_registration()
+core.registered_craft_predicts, core.register_craft_predict = make_registration()
+core.registered_on_protection_violation, core.register_on_protection_violation = make_registration()
+core.registered_on_item_eats, core.register_on_item_eat = make_registration()
+core.registered_on_punchplayers, core.register_on_punchplayer = make_registration()
+core.registered_on_priv_grant, core.register_on_priv_grant = make_registration()
+core.registered_on_priv_revoke, core.register_on_priv_revoke = make_registration()
+core.registered_on_authplayers, core.register_on_authplayer = make_registration()
+core.registered_can_bypass_userlimit, core.register_can_bypass_userlimit = make_registration()
+core.registered_on_modchannel_message, core.register_on_modchannel_message = make_registration()
+core.registered_on_player_inventory_actions, core.register_on_player_inventory_action = make_registration()
+core.registered_allow_player_inventory_actions, core.register_allow_player_inventory_action = make_registration()
+core.registered_on_rightclickplayers, core.register_on_rightclickplayer = make_registration()
+core.registered_on_liquid_transformed, core.register_on_liquid_transformed = make_registration()
+
+--
+-- Compatibility for on_mapgen_init()
+--
+
+core.register_on_mapgen_init = function(func) func(core.get_mapgen_params()) end

builtin/game/statbars.lua

@@ -0,0 +1,187 @@
+-- cache setting
+local enable_damage = core.settings:get_bool("enable_damage")
+
+local bar_definitions = {
+	hp = {
+		hud_elem_type = "statbar",
+		position = {x = 0.5, y = 1},
+		text = "heart.png",
+		text2 = "heart_gone.png",
+		number = core.PLAYER_MAX_HP_DEFAULT,
+		item = core.PLAYER_MAX_HP_DEFAULT,
+		direction = 0,
+		size = {x = 24, y = 24},
+		offset = {x = (-10 * 24) - 25, y = -(48 + 24 + 16)},
+	},
+	breath = {
+		hud_elem_type = "statbar",
+		position = {x = 0.5, y = 1},
+		text = "bubble.png",
+		text2 = "bubble_gone.png",
+		number = core.PLAYER_MAX_BREATH_DEFAULT * 2,
+		item = core.PLAYER_MAX_BREATH_DEFAULT * 2,
+		direction = 0,
+		size = {x = 24, y = 24},
+		offset = {x = 25, y= -(48 + 24 + 16)},
+	},
+}
+
+local hud_ids = {}
+
+local function scaleToHudMax(player, field)
+	-- Scale "hp" or "breath" to the hud maximum dimensions
+	local current = player["get_" .. field](player)
+	local nominal = bar_definitions[field].item
+	local max_display = math.max(player:get_properties()[field .. "_max"], current)
+	return math.ceil(current / max_display * nominal)
+end
+
+local function update_builtin_statbars(player)
+	local name = player:get_player_name()
+
+	if name == "" then
+		return
+	end
+
+	local flags = player:hud_get_flags()
+	if not hud_ids[name] then
+		hud_ids[name] = {}
+		-- flags are not transmitted to client on connect, we need to make sure
+		-- our current flags are transmitted by sending them actively
+		player:hud_set_flags(flags)
+	end
+	local hud = hud_ids[name]
+
+	local immortal = player:get_armor_groups().immortal == 1
+
+	if flags.healthbar and enable_damage and not immortal then
+		local number = scaleToHudMax(player, "hp")
+		if hud.id_healthbar == nil then
+			local hud_def = table.copy(bar_definitions.hp)
+			hud_def.number = number
+			hud.id_healthbar = player:hud_add(hud_def)
+		else
+			player:hud_change(hud.id_healthbar, "number", number)
+		end
+	elseif hud.id_healthbar then
+		player:hud_remove(hud.id_healthbar)
+		hud.id_healthbar = nil
+	end
+
+	local show_breathbar = flags.breathbar and enable_damage and not immortal
+
+	local breath     = player:get_breath()
+	local breath_max = player:get_properties().breath_max
+	if show_breathbar and breath <= breath_max then
+		local number = scaleToHudMax(player, "breath")
+		if not hud.id_breathbar and breath < breath_max then
+			local hud_def = table.copy(bar_definitions.breath)
+			hud_def.number = number
+			hud.id_breathbar = player:hud_add(hud_def)
+		elseif hud.id_breathbar then
+			player:hud_change(hud.id_breathbar, "number", number)
+		end
+	end
+
+	if hud.id_breathbar and (not show_breathbar or breath == breath_max) then
+		core.after(1, function(player_name, breath_bar)
+			local player = core.get_player_by_name(player_name)
+			if player then
+				player:hud_remove(breath_bar)
+			end
+		end, name, hud.id_breathbar)
+		hud.id_breathbar = nil
+	end
+end
+
+local function cleanup_builtin_statbars(player)
+	local name = player:get_player_name()
+
+	if name == "" then
+		return
+	end
+
+	hud_ids[name] = nil
+end
+
+local function player_event_handler(player,eventname)
+	assert(player:is_player())
+
+	local name = player:get_player_name()
+
+	if name == "" or not hud_ids[name] then
+		return
+	end
+
+	if eventname == "health_changed" then
+		update_builtin_statbars(player)
+
+		if hud_ids[name].id_healthbar then
+			return true
+		end
+	end
+
+	if eventname == "breath_changed" then
+		update_builtin_statbars(player)
+
+		if hud_ids[name].id_breathbar then
+			return true
+		end
+	end
+
+	if eventname == "hud_changed" or eventname == "properties_changed" then
+		update_builtin_statbars(player)
+		return true
+	end
+
+	return false
+end
+
+function core.hud_replace_builtin(hud_name, definition)
+	if type(definition) ~= "table" or
+			definition.hud_elem_type ~= "statbar" then
+		return false
+	end
+
+	definition = table.copy(definition)
+
+	if hud_name == "health" then
+		definition.item = definition.item or definition.number or core.PLAYER_MAX_HP_DEFAULT
+		bar_definitions.hp = definition
+
+		for name, ids in pairs(hud_ids) do
+			local player = core.get_player_by_name(name)
+			if player and ids.id_healthbar then
+				player:hud_remove(ids.id_healthbar)
+				ids.id_healthbar = nil
+				update_builtin_statbars(player)
+			end
+		end
+		return true
+	end
+
+	if hud_name == "breath" then
+		definition.item = definition.item or definition.number or core.PLAYER_MAX_BREATH_DEFAULT
+		bar_definitions.breath = definition
+
+		for name, ids in pairs(hud_ids) do
+			local player = core.get_player_by_name(name)
+			if player and ids.id_breathbar then
+				player:hud_remove(ids.id_breathbar)
+				ids.id_breathbar = nil
+				update_builtin_statbars(player)
+			end
+		end
+		return true
+	end
+
+	return false
+end
+
+-- Append "update_builtin_statbars" as late as possible
+-- This ensures that the HUD is hidden when the flags are updated in this callback
+core.register_on_mods_loaded(function()
+	core.register_on_joinplayer(update_builtin_statbars)
+end)
+core.register_on_leaveplayer(cleanup_builtin_statbars)
+core.register_playerevent(player_event_handler)

builtin/game/static_spawn.lua

@@ -0,0 +1,23 @@
+-- Minetest: builtin/static_spawn.lua
+
+local static_spawnpoint_string = core.settings:get("static_spawnpoint")
+if static_spawnpoint_string and
+		static_spawnpoint_string ~= "" and
+		not core.setting_get_pos("static_spawnpoint") then
+	error('The static_spawnpoint setting is invalid: "' ..
+			static_spawnpoint_string .. '"')
+end
+
+local function put_player_in_spawn(player_obj)
+	local static_spawnpoint = core.setting_get_pos("static_spawnpoint")
+	if not static_spawnpoint then
+		return false
+	end
+	core.log("action", "Moving " .. player_obj:get_player_name() ..
+		" to static spawnpoint at " .. core.pos_to_string(static_spawnpoint))
+	player_obj:set_pos(static_spawnpoint)
+	return true
+end
+
+core.register_on_newplayer(put_player_in_spawn)
+core.register_on_respawnplayer(put_player_in_spawn)

builtin/game/voxelarea.lua

@@ -0,0 +1,134 @@
+local math_floor = math.floor
+local vector_new = vector.new
+
+VoxelArea = {
+	MinEdge = vector_new(1, 1, 1),
+	MaxEdge = vector_new(0, 0, 0),
+	ystride = 0,
+	zstride = 0,
+}
+
+function VoxelArea:new(o)
+	o = o or {}
+	setmetatable(o, self)
+	self.__index = self
+
+	local e = o:getExtent()
+	o.ystride = e.x
+	o.zstride = e.x * e.y
+
+	return o
+end
+
+function VoxelArea:getExtent()
+	local MaxEdge, MinEdge = self.MaxEdge, self.MinEdge
+	return vector_new(
+		MaxEdge.x - MinEdge.x + 1,
+		MaxEdge.y - MinEdge.y + 1,
+		MaxEdge.z - MinEdge.z + 1
+	)
+end
+
+function VoxelArea:getVolume()
+	local e = self:getExtent()
+	return e.x * e.y * e.z
+end
+
+function VoxelArea:index(x, y, z)
+	local MinEdge = self.MinEdge
+	local i = (z - MinEdge.z) * self.zstride +
+			  (y - MinEdge.y) * self.ystride +
+			  (x - MinEdge.x) + 1
+	return math_floor(i)
+end
+
+function VoxelArea:indexp(p)
+	local MinEdge = self.MinEdge
+	local i = (p.z - MinEdge.z) * self.zstride +
+			  (p.y - MinEdge.y) * self.ystride +
+			  (p.x - MinEdge.x) + 1
+	return math_floor(i)
+end
+
+function VoxelArea:position(i)
+	local MinEdge = self.MinEdge
+
+	i = i - 1
+
+	local z = math_floor(i / self.zstride) + MinEdge.z
+	i = i % self.zstride
+
+	local y = math_floor(i / self.ystride) + MinEdge.y
+	i = i % self.ystride
+
+	local x = math_floor(i) + MinEdge.x
+
+	return vector_new(x, y, z)
+end
+
+function VoxelArea:contains(x, y, z)
+	local MaxEdge, MinEdge = self.MaxEdge, self.MinEdge
+	return (x >= MinEdge.x) and (x <= MaxEdge.x) and
+		   (y >= MinEdge.y) and (y <= MaxEdge.y) and
+		   (z >= MinEdge.z) and (z <= MaxEdge.z)
+end
+
+function VoxelArea:containsp(p)
+	local MaxEdge, MinEdge = self.MaxEdge, self.MinEdge
+	return (p.x >= MinEdge.x) and (p.x <= MaxEdge.x) and
+		   (p.y >= MinEdge.y) and (p.y <= MaxEdge.y) and
+		   (p.z >= MinEdge.z) and (p.z <= MaxEdge.z)
+end
+
+function VoxelArea:containsi(i)
+	return (i >= 1) and (i <= self:getVolume())
+end
+
+function VoxelArea:iter(minx, miny, minz, maxx, maxy, maxz)
+	local i = self:index(minx, miny, minz) - 1
+	local xrange = maxx - minx + 1
+	local nextaction = i + 1 + xrange
+
+	local y = 0
+	local yrange = maxy - miny + 1
+	local yreqstride = self.ystride - xrange
+
+	local z = 0
+	local zrange = maxz - minz + 1
+	local multistride = self.zstride - ((yrange - 1) * self.ystride + xrange)
+
+	return function()
+		-- continue i until it needs to jump
+		i = i + 1
+		if i ~= nextaction then
+			return i
+		end
+
+		-- continue y until maxy is exceeded
+		y = y + 1
+		if y ~= yrange then
+			-- set i to index(minx, miny + y, minz + z) - 1
+			i = i + yreqstride
+			nextaction = i + xrange
+			return i
+		end
+
+		-- continue z until maxz is exceeded
+		z = z + 1
+		if z == zrange then
+			-- cuboid finished, return nil
+			return
+		end
+
+		-- set i to index(minx, miny, minz + z) - 1
+		i = i + multistride
+
+		y = 0
+		nextaction = i + xrange
+		return i
+	end
+end
+
+function VoxelArea:iterp(minp, maxp)
+	return self:iter(minp.x, minp.y, minp.z, maxp.x, maxp.y, maxp.z)
+end