Replace old cart mod on boost_cart

games/default/files/boost_cart/README.txt

@@ -0,0 +1,57 @@
+ Minetest mod: boost_cart
+==========================
+Based on (and fully compatible with) the mod "carts" by PilzAdam
+and the one contained in the subgame "minetest_game".
+Target: Run smoothly as possible, even on laggy servers.
+
+
+ Features
+----------
+- A fast cart for your railway or roller coaster
+- Easily configurable cart speed using the Advanced Settings
+- Boost and brake rails
+- By mesecons controlled Start-Stop rails
+- Detector rails that send a mesecons signal when the cart drives over them
+- Rail junction switching with the 'right/left' walking keys
+- Handbrake with the 'back' key
+- Support for non-minetest_game subgames
+
+
+ Settings
+----------
+This mod can be adjusted to fit the conditions of a player or server.
+Use the Advanced Settings dialog in the main menu or tune your
+minetest.conf file manually:
+
+boost_cart.speed_max = 10
+   ^ Possible values: 1 ... 100
+   ^ Maximal speed of the cart in m/s
+
+boost_cart.punch_speed_max = 7
+   ^ Possible values: -1 ... 100
+   ^ Maximal speed to which the driving player can accelerate the cart
+     by punching from inside the cart. -1 will disable this feature.
+
+
+Carts, based almost entirely on the mod boost_cart [1], which
+itself is based on (and fully compatible with) the carts mod [2].
+
+The model was originally designed by stujones11 [3] (CC-0).
+
+Cart textures are based on original work from PixelBOX by Gambit (permissive
+license).
+
+[1] https://github.com/SmallJoker/boost_cart/
+[2] https://github.com/PilzAdam/carts/
+[3] https://github.com/stujones11/railcart/
+
+
+ Authors
+---------
+Various authors
+	carts_rail_*.png
+
+
+klankbeeld (CC-BY 3.0)
+	http://freesound.org/people/klankbeeld/sounds/174042/
+	cart_rail.*.ogg

games/default/files/boost_cart/cart_entity.lua

@@ -0,0 +1,475 @@
+
+local HAVE_MESECONS_ENABLED = minetest.global_exists("mesecon")
+
+function boost_cart:on_rail_step(entity, pos, distance)
+	-- Play rail sound
+	if entity.sound_counter <= 0 then
+		minetest.sound_play("cart_rail", {
+			pos = pos,
+			max_hear_distance = 40,
+			gain = 0.5
+		})
+		entity.sound_counter = math.random(4, 15)
+	end
+	entity.sound_counter = entity.sound_counter - distance
+
+	if HAVE_MESECONS_ENABLED then
+		boost_cart:signal_detector_rail(pos)
+	end
+end
+
+local cart_entity = {
+	initial_properties = {
+		physical = false,
+		collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
+		visual = "mesh",
+		mesh = "carts_cart.b3d",
+		visual_size = {x=1, y=1},
+		textures = {"carts_cart.png"},
+	},
+
+	driver = nil,
+	punched = false, -- used to re-send velocity and position
+	velocity = {x=0, y=0, z=0}, -- only used on punch
+	old_dir = {x=1, y=0, z=0}, -- random value to start the cart on punch
+	old_pos = nil,
+	old_switch = 0,
+	sound_counter = 0,
+	railtype = nil,
+	attached_items = {}
+}
+
+function cart_entity:on_rightclick(clicker)
+	if not clicker or not clicker:is_player() then
+		return
+	end
+	local player_name = clicker:get_player_name()
+	if self.driver and player_name == self.driver then
+		self.driver = nil
+		boost_cart:manage_attachment(clicker, nil)
+	elseif not self.driver then
+		self.driver = player_name
+		boost_cart:manage_attachment(clicker, self.object)
+
+		if default.player_set_animation then
+			-- player_api(/default) does not update the animation
+			-- when the player is attached, reset to default animation
+			default.player_set_animation(clicker, "stand")
+		end
+	end
+end
+
+function cart_entity:on_activate(staticdata, dtime_s)
+	self.object:set_armor_groups({immortal=1})
+	self.sound_counter = math.random(4, 15)
+
+	if string.sub(staticdata, 1, string.len("return")) ~= "return" then
+		return
+	end
+	local data = minetest.deserialize(staticdata)
+	if type(data) ~= "table" then
+		return
+	end
+	self.railtype = data.railtype
+	self.old_dir = data.old_dir or self.old_dir
+	self.old_pos = data.old_pos or self.old_pos
+	-- Correct the position when the cart drives further after the last 'step()'
+	if self.old_pos and boost_cart:is_rail(self.old_pos, self.railtype) then
+		self.object:set_pos(self.old_pos)
+	end
+end
+
+function cart_entity:get_staticdata()
+	return minetest.serialize({
+		railtype = self.railtype,
+		old_dir = self.old_dir,
+		old_pos = self.old_pos
+	})
+end
+
+-- 0.5.x and later: When the driver leaves
+function cart_entity:on_detach_child(child)
+	if child and child:get_player_name() == self.driver then
+		self.driver = nil
+	end
+end
+
+function cart_entity:on_punch(puncher, time_from_last_punch, tool_capabilities, direction)
+	local pos = self.object:get_pos()
+	local vel = self.object:get_velocity()
+	if not self.railtype or vector.equals(vel, {x=0, y=0, z=0}) then
+		local node = minetest.get_node(pos).name
+		self.railtype = minetest.get_item_group(node, "connect_to_raillike")
+	end
+
+	if not puncher or not puncher:is_player() then
+		local cart_dir = boost_cart:get_rail_direction(pos, self.old_dir, nil, nil, self.railtype)
+		if vector.equals(cart_dir, {x=0, y=0, z=0}) then
+			return
+		end
+		self.velocity = vector.multiply(cart_dir, 3)
+		self.punched = true
+		return
+	end
+
+	if puncher:get_player_control().sneak then
+		-- Pick up cart: Drop all attachments
+		if self.driver then
+			if self.old_pos then
+				self.object:set_pos(self.old_pos)
+			end
+			local player = minetest.get_player_by_name(self.driver)
+			boost_cart:manage_attachment(player, nil)
+		end
+		for _, obj_ in pairs(self.attached_items) do
+			if obj_ then
+				obj_:set_detach()
+			end
+		end
+
+		local leftover = puncher:get_inventory():add_item("main", "carts:cart")
+		if not leftover:is_empty() then
+			minetest.add_item(pos, leftover)
+		end
+
+		self.object:remove()
+		return
+	end
+
+	-- Driver punches to accelerate the cart
+	if puncher:get_player_name() == self.driver then
+		if math.abs(vel.x + vel.z) > boost_cart.punch_speed_max then
+			return
+		end
+	end
+
+	local punch_dir = boost_cart:velocity_to_dir(puncher:get_look_dir())
+	punch_dir.y = 0
+	local cart_dir = boost_cart:get_rail_direction(pos, punch_dir, nil, nil, self.railtype)
+	if vector.equals(cart_dir, {x=0, y=0, z=0}) then
+		return
+	end
+
+	local punch_interval = 1
+	if tool_capabilities and tool_capabilities.full_punch_interval then
+		punch_interval = tool_capabilities.full_punch_interval
+	end
+	time_from_last_punch = math.min(time_from_last_punch or punch_interval, punch_interval)
+	local f = 3 * (time_from_last_punch / punch_interval)
+
+	self.velocity = vector.multiply(cart_dir, f)
+	self.old_dir = cart_dir
+	self.punched = true
+end
+
+-- sound refresh interval = 1.0sec
+local function rail_sound(self, dtime)
+	if not self.sound_ttl then
+		self.sound_ttl = 1.0
+		return
+	elseif self.sound_ttl > 0 then
+		self.sound_ttl = self.sound_ttl - dtime
+		return
+	end
+	self.sound_ttl = 1.0
+	if self.sound_handle then
+		local handle = self.sound_handle
+		self.sound_handle = nil
+		minetest.after(0.2, minetest.sound_stop, handle)
+	end
+	local vel = self.object:get_velocity()
+	local speed = vector.length(vel)
+	if speed > 0 then
+		self.sound_handle = minetest.sound_play(
+			"carts_cart_moving", {
+			object = self.object,
+			gain = (speed / boost_cart.speed_max) / 2,
+			loop = true,
+		})
+	end
+end
+
+
+local v3_len = vector.length
+function cart_entity:on_step(dtime)
+	rail_sound(self, dtime)
+	local vel = self.object:get_velocity()
+	if self.punched then
+		vel = vector.add(vel, self.velocity)
+		self.object:set_velocity(vel)
+		self.old_dir.y = 0
+	elseif vector.equals(vel, {x=0, y=0, z=0}) then
+		return
+	end
+
+	local pos = self.object:get_pos()
+	local cart_dir = boost_cart:velocity_to_dir(vel)
+	local same_dir = vector.equals(cart_dir, self.old_dir)
+	local update = {}
+
+	if self.old_pos and not self.punched and same_dir then
+		local flo_pos = vector.round(pos)
+		local flo_old = vector.round(self.old_pos)
+		if vector.equals(flo_pos, flo_old) then
+			-- Do not check one node multiple times
+			return
+		end
+	end
+
+	local ctrl, player
+	local distance = 1
+
+	-- Get player controls
+	if self.driver then
+		player = minetest.get_player_by_name(self.driver)
+		if player then
+			ctrl = player:get_player_control()
+		end
+	end
+
+	local stop_wiggle = false
+	if self.old_pos and same_dir then
+		-- Detection for "skipping" nodes (perhaps use average dtime?)
+		-- It's sophisticated enough to take the acceleration in account
+		local acc = self.object:get_acceleration()
+		distance = dtime * (v3_len(vel) + 0.5 * dtime * v3_len(acc))
+
+		local new_pos, new_dir = boost_cart:pathfinder(
+			pos, self.old_pos, self.old_dir, distance, ctrl,
+			self.old_switch, self.railtype
+		)
+
+		if new_pos then
+			-- No rail found: set to the expected position
+			pos = new_pos
+			update.pos = true
+			cart_dir = new_dir
+		end
+	elseif self.old_pos and self.old_dir.y ~= 1 and not self.punched then
+		-- Stop wiggle
+		stop_wiggle = true
+	end
+
+	-- dir:			New moving direction of the cart
+	-- switch_keys:	Currently pressed L(1) or R(2) key,
+	--				used to ignore the key on the next rail node
+	local dir, switch_keys = boost_cart:get_rail_direction(
+		pos, cart_dir, ctrl, self.old_switch, self.railtype
+	)
+	local dir_changed = not vector.equals(dir, self.old_dir)
+
+	local acc = 0
+	if stop_wiggle or vector.equals(dir, {x=0, y=0, z=0}) then
+		vel = {x=0, y=0, z=0}
+		local pos_r = vector.round(pos)
+		if not boost_cart:is_rail(pos_r, self.railtype)
+				and self.old_pos then
+			pos = self.old_pos
+		elseif not stop_wiggle then
+			pos = pos_r
+		else
+			pos.y = math.floor(pos.y + 0.5)
+		end
+		update.pos = true
+		update.vel = true
+	else
+		-- Direction change detected
+		if dir_changed then
+			vel = vector.multiply(dir, math.abs(vel.x + vel.z))
+			update.vel = true
+			if dir.y ~= self.old_dir.y then
+				pos = vector.round(pos)
+				update.pos = true
+			end
+		end
+		-- Center on the rail
+		if dir.z ~= 0 and math.floor(pos.x + 0.5) ~= pos.x then
+			pos.x = math.floor(pos.x + 0.5)
+			update.pos = true
+		end
+		if dir.x ~= 0 and math.floor(pos.z + 0.5) ~= pos.z then
+			pos.z = math.floor(pos.z + 0.5)
+			update.pos = true
+		end
+
+		-- Calculate current cart acceleration
+		acc = nil
+
+		local acc_meta = minetest.get_meta(pos):get_string("cart_acceleration")
+		if acc_meta == "halt" and not self.punched then
+			-- Stop rail
+			vel = {x=0, y=0, z=0}
+			acc = false
+			pos = vector.round(pos)
+			update.pos = true
+			update.vel = true
+		end
+		if acc == nil then
+			-- Meta speed modifier
+			local speed_mod = tonumber(acc_meta)
+			if speed_mod and speed_mod ~= 0 then
+				-- Try to make it similar to the original carts mod
+				acc = speed_mod * 10
+			end
+		end
+		if acc == nil and boost_cart.mtg_compat then
+			-- MTG Cart API adaption
+			local rail_node = minetest.get_node(vector.round(pos))
+			local railparam = carts.railparams[rail_node.name]
+			if railparam and railparam.acceleration then
+				acc = railparam.acceleration
+			end
+		end
+		if acc ~= false then
+			-- Handbrake
+			if ctrl and ctrl.down then
+				acc = (acc or 0) - 2
+			elseif acc == nil then
+				acc = -0.4
+			end
+		end
+
+		if acc then
+			-- Slow down or speed up, depending on Y direction
+			acc = acc + dir.y * -2.1
+		else
+			acc = 0
+		end
+	end
+
+	-- Limit cart speed
+	local vel_len = vector.length(vel)
+	if vel_len > boost_cart.speed_max then
+		vel = vector.multiply(vel, boost_cart.speed_max / vel_len)
+		update.vel = true
+	end
+	if vel_len >= boost_cart.speed_max and acc > 0 then
+		acc = 0
+	end
+
+	self.object:set_acceleration(vector.multiply(dir, acc))
+
+	self.old_pos = vector.round(pos)
+	local old_y_dir = self.old_dir.y
+	if not vector.equals(dir, {x=0, y=0, z=0}) and not stop_wiggle then
+		self.old_dir = dir
+	else
+		-- Cart stopped, set the animation to 0
+		self.old_dir.y = 0
+	end
+	self.old_switch = switch_keys
+
+	boost_cart:on_rail_step(self, self.old_pos, distance)
+
+	if self.punched then
+		-- Collect dropped items
+		for _, obj_ in pairs(minetest.get_objects_inside_radius(pos, 1)) do
+			if not obj_:is_player() and
+					obj_:get_luaentity() and
+					not obj_:get_luaentity().physical_state and
+					obj_:get_luaentity().name == "__builtin:item" then
+
+				obj_:set_attach(self.object, "", {x=0, y=0, z=0}, {x=0, y=0, z=0})
+				self.attached_items[#self.attached_items + 1] = obj_
+			end
+		end
+		self.punched = false
+		update.vel = true
+	end
+
+	if not (update.vel or update.pos) then
+		return
+	end
+	-- Re-use "dir", localize self.old_dir
+	dir = self.old_dir
+
+	local yaw = 0
+	if dir.x < 0 then
+		yaw = 0.5
+	elseif dir.x > 0 then
+		yaw = 1.5
+	elseif dir.z < 0 then
+		yaw = 1
+	end
+	self.object:set_yaw(yaw * math.pi)
+
+	local anim = {x=0, y=0}
+	if dir.y == -1 then
+		anim = {x=1, y=1}
+	elseif dir.y == 1 then
+		anim = {x=2, y=2}
+	end
+	self.object:set_animation(anim, 1, 0)
+
+	-- Change player model rotation, depending on the Y direction
+	if player and dir.y ~= old_y_dir then
+		local feet = {x=0, y=0, z=0}
+		local eye = {x=0, y=-4, z=0}
+		feet.y = boost_cart.old_player_model and 6 or -4
+		if dir.y ~= 0 then
+			-- TODO: Find a better way to calculate this
+			if boost_cart.old_player_model then
+				feet.y = feet.y + 2
+				feet.z = -dir.y * 6
+			else
+				feet.y = feet.y + 4
+				feet.z = -dir.y * 2
+			end
+			eye.z = -dir.y * 8
+		end
+		player:set_attach(self.object, "", feet,
+			{x=dir.y * -30, y=0, z=0})
+		player:set_eye_offset(eye, eye)
+	end
+
+	if update.vel then
+		self.object:set_velocity(vel)
+	end
+	if update.pos then
+		if dir_changed then
+			self.object:set_pos(pos)
+		else
+			self.object:move_to(pos)
+		end
+	end
+end
+
+minetest.register_entity(":carts:cart", cart_entity)
+
+-- Register item to place the entity
+if not boost_cart.mtg_compat then
+	minetest.register_craftitem(":carts:cart", {
+		description = "Cart (Sneak+Click to pick up)",
+		inventory_image = minetest.inventorycube(
+			"cart_top.png",
+			"cart_side.png",
+			"cart_side.png"
+		),
+		wield_image = "cart_side.png",
+		on_place = function(itemstack, placer, pointed_thing)
+			if not pointed_thing.type == "node" then
+				return
+			end
+			if boost_cart:is_rail(pointed_thing.under) then
+				minetest.add_entity(pointed_thing.under, "carts:cart")
+			elseif boost_cart:is_rail(pointed_thing.above) then
+				minetest.add_entity(pointed_thing.above, "carts:cart")
+			else
+				return
+			end
+
+			if not minetest.settings:get_bool("creative_mode") then
+				itemstack:take_item()
+			end
+			return itemstack
+		end,
+	})
+
+	minetest.register_craft({
+		output = "carts:cart",
+		recipe = {
+			{"default:steel_ingot", "", "default:steel_ingot"},
+			{"default:steel_ingot", "default:steel_ingot", "default:steel_ingot"},
+		},
+	})
+end

games/default/files/boost_cart/depends.txt

@@ -0,0 +1,4 @@
+default
+mesecons?
+moreores?
+carts?

games/default/files/boost_cart/description.txt

@@ -0,0 +1 @@
+This mod offers improved minecarts and a few more rail types.

games/default/files/boost_cart/detector.lua

@@ -0,0 +1,58 @@
+local mesecons_rules = mesecon.rules.flat
+
+function boost_cart:turnoff_detector_rail(pos)
+	local node = minetest.get_node(pos)
+	if minetest.get_item_group(node.name, "detector_rail") == 1 then
+		if node.name == "boost_cart:detectorrail_on" then --has not been dug
+			minetest.swap_node(pos, {name = "boost_cart:detectorrail", param2=node.param2})
+		end
+		mesecon.receptor_off(pos, mesecons_rules)
+	end
+end
+
+function boost_cart:signal_detector_rail(pos)
+	local node = minetest.get_node(pos)
+	if minetest.get_item_group(node.name, "detector_rail") ~= 1 then
+		return
+	end
+
+	if node.name == "boost_cart:detectorrail" then
+		minetest.swap_node(pos, {name = "boost_cart:detectorrail_on", param2=node.param2})
+	end
+	mesecon.receptor_on(pos, mesecons_rules)
+	minetest.after(0.5, boost_cart.turnoff_detector_rail, boost_cart, pos)
+end
+
+boost_cart:register_rail("boost_cart:detectorrail", {
+	description = "Detector rail",
+	tiles = {
+		"carts_rail_straight_dtc.png", "carts_rail_curved_dtc.png",
+		"carts_rail_t_junction_dtc.png", "carts_rail_crossing_dtc.png"
+	},
+	groups = boost_cart:get_rail_groups({detector_rail = 1}),
+
+	mesecons = {receptor = {state = "off", rules = mesecons_rules}},
+})
+
+boost_cart:register_rail("boost_cart:detectorrail_on", {
+	description = "Detector rail ON (you hacker you)",
+	tiles = {
+		"carts_rail_straight_dtc_on.png", "carts_rail_curved_dtc_on.png",
+		"carts_rail_t_junction_dtc_on.png", "carts_rail_crossing_dtc_on.png"
+	},
+	groups = boost_cart:get_rail_groups({
+		detector_rail = 1, not_in_creative_inventory = 1
+	}),
+	drop = "boost_cart:detectorrail",
+
+	mesecons = {receptor = {state = "on", rules = mesecons_rules}},
+})
+
+minetest.register_craft({
+	output = "boost_cart:detectorrail 6",
+	recipe = {
+		{"default:steel_ingot", "", "default:steel_ingot"},
+		{"default:steel_ingot", "mesecons_pressureplates:pressure_plate_stone_off", "default:steel_ingot"},
+		{"default:steel_ingot", "mesecons:wire_00000000_off", "default:steel_ingot"},
+	},
+})

games/default/files/boost_cart/functions.lua

@@ -0,0 +1,269 @@
+function boost_cart:get_sign(z)
+	if z == 0 then
+		return 0
+	else
+		return z / math.abs(z)
+	end
+end
+
+function boost_cart:manage_attachment(player, obj)
+	if not player then
+		return
+	end
+	local status = obj ~= nil
+	local player_name = player:get_player_name()
+	if default.player_attached[player_name] == status then
+		return
+	end
+	default.player_attached[player_name] = status
+
+	if status then
+		local y_pos = self.old_player_model and 6 or -4
+		if player:get_properties().visual == "upright_sprite" then
+			y_pos = -4
+		end
+		player:set_attach(obj, "", {x=0, y=y_pos, z=0}, {x=0, y=0, z=0})
+		player:set_eye_offset({x=0, y=-4, z=0},{x=0, y=-4, z=0})
+	else
+		player:set_detach()
+		player:set_eye_offset({x=0, y=0, z=0},{x=0, y=0, z=0})
+		-- HACK in effect! Force updating the attachment rotation
+		player:set_properties({})
+	end
+end
+
+function boost_cart:velocity_to_dir(v)
+	if math.abs(v.x) > math.abs(v.z) then
+		return {x=self:get_sign(v.x), y=self:get_sign(v.y), z=0}
+	else
+		return {x=0, y=self:get_sign(v.y), z=self:get_sign(v.z)}
+	end
+end
+
+local get_node = minetest.get_node
+local get_item_group = minetest.get_item_group
+function boost_cart:is_rail(pos, railtype)
+	local node = get_node(pos).name
+	if node == "ignore" then
+		local vm = minetest.get_voxel_manip()
+		local emin, emax = vm:read_from_map(pos, pos)
+		local area = VoxelArea:new{
+			MinEdge = emin,
+			MaxEdge = emax,
+		}
+		local data = vm:get_data()
+		local vi = area:indexp(pos)
+		node = minetest.get_name_from_content_id(data[vi])
+	end
+	if get_item_group(node, "rail") == 0 then
+		return false
+	end
+	if not railtype then
+		return true
+	end
+	return get_item_group(node, "connect_to_raillike") == railtype
+end
+
+function boost_cart:check_front_up_down(pos, dir_, check_up, railtype)
+	local dir = vector.new(dir_)
+	local cur = nil
+
+	-- Front
+	dir.y = 0
+	cur = vector.add(pos, dir)
+	if self:is_rail(cur, railtype) then
+		return dir
+	end
+	-- Up
+	if check_up then
+		dir.y = 1
+		cur = vector.add(pos, dir)
+		if self:is_rail(cur, railtype) then
+			return dir
+		end
+	end
+	-- Down
+	dir.y = -1
+	cur = vector.add(pos, dir)
+	if self:is_rail(cur, railtype) then
+		return dir
+	end
+	return nil
+end
+
+function boost_cart:get_rail_direction(pos_, dir, ctrl, old_switch, railtype)
+	local pos = vector.round(pos_)
+	local cur = nil
+	local left_check, right_check = true, true
+
+	-- Check left and right
+	local left = {x=0, y=0, z=0}
+	local right = {x=0, y=0, z=0}
+	if dir.z ~= 0 and dir.x == 0 then
+		left.x = -dir.z
+		right.x = dir.z
+	elseif dir.x ~= 0 and dir.z == 0 then
+		left.z = dir.x
+		right.z = -dir.x
+	end
+
+	local straight_priority = ctrl and dir.y ~= 0
+
+	-- Normal, to disallow rail switching up- & downhill
+	if straight_priority then
+		cur = self:check_front_up_down(pos, dir, true, railtype)
+		if cur then
+			return cur
+		end
+	end
+
+	if ctrl then
+		if old_switch == 1 then
+			left_check = false
+		elseif old_switch == 2 then
+			right_check = false
+		end
+		if ctrl.left and left_check then
+			cur = self:check_front_up_down(pos, left, false, railtype)
+			if cur then
+				return cur, 1
+			end
+			left_check = false
+		end
+		if ctrl.right and right_check then
+			cur = self:check_front_up_down(pos, right, false, railtype)
+			if cur then
+				return cur, 2
+			end
+			right_check = true
+		end
+	end
+
+	-- Normal
+	if not straight_priority then
+		cur = self:check_front_up_down(pos, dir, true, railtype)
+		if cur then
+			return cur
+		end
+	end
+
+	-- Left, if not already checked
+	if left_check then
+		cur = self:check_front_up_down(pos, left, false, railtype)
+		if cur then
+			return cur
+		end
+	end
+
+	-- Right, if not already checked
+	if right_check then
+		cur = self:check_front_up_down(pos, right, false, railtype)
+		if cur then
+			return cur
+		end
+	end
+
+	-- Backwards
+	if not old_switch then
+		cur = self:check_front_up_down(pos, {
+				x = -dir.x,
+				y = dir.y,
+				z = -dir.z
+			}, true, railtype)
+		if cur then
+			return cur
+		end
+	end
+
+	return {x=0, y=0, z=0}
+end
+
+function boost_cart:pathfinder(pos_, old_pos, old_dir, distance, ctrl,
+		pf_switch, railtype)
+
+	local pos = vector.round(pos_)
+	if vector.equals(old_pos, pos) then
+		return
+	end
+
+	local pf_pos = vector.round(old_pos)
+	local pf_dir = vector.new(old_dir)
+	distance = math.min(boost_cart.path_distance_max,
+		math.floor(distance + 1))
+
+	for i = 1, distance do
+		pf_dir, pf_switch = self:get_rail_direction(
+			pf_pos, pf_dir, ctrl, pf_switch or 0, railtype)
+
+		if vector.equals(pf_dir, {x=0, y=0, z=0}) then
+			-- No way forwards
+			return pf_pos, pf_dir
+		end
+
+		pf_pos = vector.add(pf_pos, pf_dir)
+
+		if vector.equals(pf_pos, pos) then
+			-- Success! Cart moved on correctly
+			return
+		end
+	end
+	-- Not found. Put cart to predicted position
+	return pf_pos, pf_dir
+end
+
+function boost_cart:boost_rail(pos, amount)
+	minetest.get_meta(pos):set_string("cart_acceleration", tostring(amount))
+	for _,obj_ in ipairs(minetest.get_objects_inside_radius(pos, 0.5)) do
+		if not obj_:is_player() and
+				obj_:get_luaentity() and
+				obj_:get_luaentity().name == "carts:cart" then
+			obj_:get_luaentity():on_punch()
+		end
+	end
+end
+
+function boost_cart:register_rail(name, def_overwrite)
+	local sound_func = default.node_sound_metal_defaults
+		or default.node_sound_defaults
+
+	local def = {
+		drawtype = "raillike",
+		paramtype = "light",
+		sunlight_propagates = true,
+		is_ground_content = false,
+		walkable = false,
+		selection_box = {
+			type = "fixed",
+			fixed = {-1/2, -1/2, -1/2, 1/2, -1/2+1/16, 1/2},
+		},
+		sounds = sound_func()
+	}
+	for k, v in pairs(def_overwrite) do
+		def[k] = v
+	end
+	if not def.inventory_image then
+		def.wield_image = def.tiles[1]
+		def.inventory_image = def.tiles[1]
+	end
+
+	minetest.register_node(name, def)
+end
+
+function boost_cart:get_rail_groups(additional_groups)
+	-- Get the default rail groups and add more when a table is given
+	local groups = {
+		dig_immediate = 2,
+		attached_node = 1,
+		rail = 1,
+		connect_to_raillike = 1
+	}
+	if minetest.raillike_group then
+		groups.connect_to_raillike = minetest.raillike_group("rail")
+	end
+	if type(additional_groups) == "table" then
+		for k, v in pairs(additional_groups) do
+			groups[k] = v
+		end
+	end
+	return groups
+end

games/default/files/boost_cart/init.lua

@@ -0,0 +1,45 @@
+boost_cart = {}
+boost_cart.modpath = minetest.get_modpath("boost_cart")
+
+local function getNum(setting)
+	return tonumber(minetest.settings:get(setting))
+end
+
+-- Maximal speed of the cart in m/s
+boost_cart.speed_max = getNum("boost_cart.speed_max") or 12
+-- Set to -1 to disable punching the cart from inside
+boost_cart.punch_speed_max = getNum("boost_cart.punch_speed_max") or 8
+-- Maximal distance for the path correction (for dtime peaks)
+boost_cart.path_distance_max = 3
+
+-- Support for non-default games
+if not default.player_attached then
+	default.player_attached = {}
+end
+
+minetest.after(0, function()
+	boost_cart.old_player_model = not minetest.global_exists("player_api")
+end)
+
+dofile(boost_cart.modpath.."/functions.lua")
+dofile(boost_cart.modpath.."/rails.lua")
+
+if minetest.global_exists("mesecon") then
+	dofile(boost_cart.modpath.."/detector.lua")
+--else
+--	minetest.register_alias("carts:powerrail", "boost_cart:detectorrail")
+--	minetest.register_alias("carts:powerrail", "boost_cart:detectorrail_on")
+end
+
+dofile(boost_cart.modpath.."/cart_entity.lua")
+
+-- Aliases
+minetest.register_alias("railcart:cart", "carts:cart")
+minetest.register_alias("railcart:cart_entity", "carts:cart")
+minetest.register_alias("default:rail", "boost_cart:rail")
+minetest.register_alias("railtrack:powerrail", "carts:powerrail")
+minetest.register_alias("railtrack:superrail", "carts:powerrail")
+minetest.register_alias("railtrack:brakerail", "carts:brakerail")
+minetest.register_alias("railtrack:switchrail", "boost_cart:startstoprail")
+minetest.register_alias("railtrack:fixer", "default:stick")
+minetest.register_alias("railtrack:inspector", "default:stick")

games/default/files/boost_cart/license.txt

@@ -0,0 +1,54 @@
+
+License of source code
+----------------------
+
+The MIT License (MIT)
+Copyright (C) 2012-2016 PilzAdam
+Copyright (C) 2014-2016 SmallJoker
+Copyright (C) 2012-2016 Various Minetest developers and contributors
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation the
+rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+For more details:
+https://opensource.org/licenses/MIT
+
+
+Licenses of media
+-----------------
+
+CC-0, see: https://creativecommons.org/share-your-work/public-domain/cc0/, except
+if other license is mentioned.
+
+
+Authors
+---------
+Originally from PixelBOX (Gambit):
+	carts_cart_side.png
+	carts_cart_top.png
+	carts_cart_front.png*
+	carts_cart.png*
+
+sofar + stujones11:
+	carts_cart.b3d and carts_cart.blend
+
+hexafraction, modified by sofar
+	carts_rail_*.png
+
+http://www.freesound.org/people/YleArkisto/sounds/253159/ - YleArkisto - CC-BY-3.0
+	carts_cart_moving.*.ogg

games/default/files/boost_cart/mod.conf

@@ -0,0 +1 @@
+name = boost_cart

games/default/files/boost_cart/rails.lua

@@ -0,0 +1,153 @@
+-- Common rail registrations
+
+boost_cart:register_rail("boost_cart:rail", {
+	description = "Rail",
+	tiles = {
+		"carts_rail_straight.png", "carts_rail_curved.png",
+		"carts_rail_t_junction.png", "carts_rail_crossing.png"
+	},
+	groups = boost_cart:get_rail_groups(),
+}, {})
+
+minetest.register_craft({
+	output = "boost_cart:rail 16",
+	recipe = {
+		{"default:steel_ingot", "", "default:steel_ingot"},
+		{"default:steel_ingot", "group:stick", "default:steel_ingot"},
+		{"default:steel_ingot", "", "default:steel_ingot"},
+	}
+})
+
+--[[
+-- Moreores' copper rail
+if minetest.get_modpath("moreores") then
+	minetest.register_alias("carts:copperrail", "moreores:copper_rail")
+
+	if minetest.raillike_group then
+		-- Ensure that this rail uses the same connect_to_raillike
+		local new_groups = minetest.registered_nodes["moreores:copper_rail"].groups
+		new_groups.connect_to_raillike = minetest.raillike_group("rail")
+		minetest.override_item("moreores:copper_rail", {
+			groups = new_groups
+		})
+	end
+else
+	boost_cart:register_rail(":carts:copperrail", {
+		description = "Copper rail",
+		tiles = {
+			"carts_rail_straight_cp.png", "carts_rail_curved_cp.png",
+			"carts_rail_t_junction_cp.png", "carts_rail_crossing_cp.png"
+		},
+		groups = boost_cart:get_rail_groups()
+	})
+
+	minetest.register_craft({
+		output = "carts:copperrail 12",
+		recipe = {
+			{"default:copper_ingot", "", "default:copper_ingot"},
+			{"default:copper_ingot", "group:stick", "default:copper_ingot"},
+			{"default:copper_ingot", "", "default:copper_ingot"},
+		}
+	})
+end
+]]
+-- Power rail
+boost_cart:register_rail(":carts:powerrail", {
+	description = "Powered rail",
+	tiles = {
+		"carts_rail_straight_pwr.png", "carts_rail_curved_pwr.png",
+		"carts_rail_t_junction_pwr.png", "carts_rail_crossing_pwr.png"
+	},
+	groups = boost_cart:get_rail_groups(),
+	after_place_node = function(pos, placer, itemstack)
+		if not mesecon then
+			minetest.get_meta(pos):set_string("cart_acceleration", "0.5")
+		end
+	end,
+	mesecons = {
+		effector = {
+			action_on = function(pos, node)
+				boost_cart:boost_rail(pos, 0.5)
+			end,
+			action_off = function(pos, node)
+				minetest.get_meta(pos):set_string("cart_acceleration", "0")
+			end,
+		},
+	},
+})
+
+minetest.register_craft({
+	output = "carts:powerrail 6",
+	recipe = {
+		{"default:gold_ingot", "", "default:gold_ingot"},
+		{"default:gold_ingot", "group:stick", "default:gold_ingot"},
+		{"default:gold_ingot", "mesecons:wire_00000000_off", "default:gold_ingot"},
+	}
+})
+
+-- Brake rail
+boost_cart:register_rail(":carts:brakerail", {
+	description = "Brake rail",
+	tiles = {
+		"carts_rail_straight_brk.png", "carts_rail_curved_brk.png",
+		"carts_rail_t_junction_brk.png", "carts_rail_crossing_brk.png"
+	},
+	groups = boost_cart:get_rail_groups(),
+	after_place_node = function(pos, placer, itemstack)
+		if not mesecon then
+			minetest.get_meta(pos):set_string("cart_acceleration", "-0.3")
+		end
+	end,
+	mesecons = {
+		effector = {
+			action_on = function(pos, node)
+				minetest.get_meta(pos):set_string("cart_acceleration", "-0.3")
+			end,
+			action_off = function(pos, node)
+				minetest.get_meta(pos):set_string("cart_acceleration", "0")
+			end,
+		},
+	},
+})
+
+minetest.register_craft({
+	output = "carts:brakerail 6",
+	recipe = {
+		{"default:steel_ingot", "default:steel_ingot", "default:steel_ingot"},
+		{"default:steel_ingot", "group:stick", "default:steel_ingot"},
+		{"default:steel_ingot", "default:steel_ingot", "default:steel_ingot"},
+	}
+})
+
+boost_cart:register_rail("boost_cart:startstoprail", {
+	description = "Start-stop rail",
+	tiles = {
+		"carts_rail_straight_ss.png", "carts_rail_curved_ss.png",
+		"carts_rail_t_junction_ss.png", "carts_rail_crossing_ss.png"
+	},
+	groups = boost_cart:get_rail_groups(),
+	after_place_node = function(pos, placer, itemstack)
+		if not mesecon then
+			minetest.get_meta(pos):set_string("cart_acceleration", "halt")
+		end
+	end,
+	mesecons = {
+		effector = {
+			action_on = function(pos, node)
+				boost_cart:boost_rail(pos, 0.5)
+			end,
+			action_off = function(pos, node)
+				minetest.get_meta(pos):set_string("cart_acceleration", "halt")
+			end,
+		},
+	},
+})
+
+minetest.register_craft({
+	output = "boost_cart:startstoprail 2",
+	recipe = {
+		{"default:steel_ingot", "group:stick", "default:steel_ingot"},
+		{"default:steel_ingot", "mesecons_torch:mesecon_torch_on", "default:steel_ingot"},
+		{"default:steel_ingot", "group:stick", "default:steel_ingot"},
+	}
+})

games/default/files/boost_cart/settingtypes.txt

@@ -0,0 +1,6 @@
+#    Maximal speed of the cart in m/s (min=1, max=100)
+boost_cart.speed_max (Maximal speed) int 10 1 100
+
+#    Maximal speed to which the driving player can accelerate the cart by punching
+#    from inside the cart. -1 will disable this feature. (min=-1, max=100)
+boost_cart.punch_speed_max (Maximal punch speed) int 7 -1 100

games/default/files/railcart/LICENSE.txt

@@ -1,21 +0,0 @@
-Minetest Mod - Railcart [railcart]
-==================================
-
-License Source Code: LGPL v2.1
-
-License of media (textures, sounds and models not otherwise specified): CC-0
-
-Authors of media files:
------------------------
-
-HybridDog: WTFPL
-
-  cart.png
-  cart_bottom.png
-  cart_side.png
-  cart_top.png
-
-Zeg9:
-
-  cart.x
-

games/default/files/railcart/README.txt

@@ -1,30 +0,0 @@
-Minetest Mod - Railcart [railcart]
-==================================
-
-Minetest version: 0.4.13
-
-Depends: railtrack
-
-Proof of concept ground up re-write of the carts mod. Currently uses media files
-borrowed from the original carts mod by PilzAdam.
-
-Please note, this mod makes heavy use of metadata so that carts are able to
-travel through unloaded map chunks, therefor a 'carts' privilege is required
-to place or pick up carts in multiplayer mode.
-
-Crafting
---------
-
-S = Steel Ingot [default:steel_ingot]
-W = Wood [group:wood]
-
-Railcart: [railcart:cart]
-
-+---+---+---+
-| S |   | S |
-+---+---+---+
-| S |   | S |
-+---+---+---+
-| W | S | W |
-+---+---+---+
-

games/default/files/railcart/depends.txt

@@ -1 +0,0 @@
-railtrack

games/default/files/railcart/init.lua

@@ -1,191 +0,0 @@
-local modpath = minetest.get_modpath(minetest.get_current_modname())
-
-dofile(modpath.."/railcart.lua")
-
-local worldpath = minetest.get_worldpath()
-
-local function create_detached_inventory(id)
-	local inv = minetest.create_detached_inventory("railcart_"..tostring(id), {
-		on_put = function(inv, listname, index, stack, player)
-			railcart:save()
-		end,
-		on_take = function(inv, listname, index, stack, player)
-			railcart:save()
-		end,
-		allow_put = function(inv, listname, index, stack, player)
-			return 1
-		end,
-		allow_take = function(inv, listname, index, stack, player)
-			return stack:get_count()
-		end,
-		allow_move = function(inv, from_list, from_index, to_list, to_index, count, player)
-			return count
-		end,
-	})
-	--inv:set_size("main", 32)
-	return inv
-end
-
-local input = io.open(worldpath.."/railcart.txt", "r")
-if input then
-	local data = input:read('*all')
-	if data then
-		local carts = minetest.deserialize(data) or {}
-		for id, ref in pairs(carts) do
-			local cart = railcart.cart:new(ref)
-			if ref.inv then
-				local inv = create_detached_inventory(cart.id)
-				for i, stack in pairs(ref.inv) do
-					inv:set_stack("main", i, stack)
-				end
-				cart.inv = inv
-			end
-			railcart.allcarts[id] = cart
-		end
-	end
-	input = nil
-end
-
-local function is_valid_player(object)
-	if object then
-		return object:is_player()
-	end
-end
-
-railcart:register_entity("railcart:cart_entity", {
-	on_punch = function(self, puncher, _, _, direction)
-		if not is_valid_player(puncher) then
-			return
-		end	
-		if puncher:get_player_control().sneak then
-			if self.cart then
-				if self.cart.id then
-					if self.cart.inv then
-						if not self.cart.inv:is_empty("main") then
-							return
-						end
-					end
-					railcart:remove_cart(self.cart.id)
-				end
-			end
-			self.object:remove()
-			local inv = puncher:get_inventory()
-			if minetest.setting_getbool("creative_mode") then
-				if not inv:contains_item("main", "railcart:cart") then
-					inv:add_item("main", "railcart:cart")
-				end
-			else
-				inv:add_item("main", "railcart:cart")
-			end
-			return
-		end
-		if self.cart and direction then
-			if self.driver then
-				direction = {x=0, y=0, z=0}
-				local ld = self.driver:get_look_dir()
-				if ld.y > -0.99 then
-					direction = {
-						x = railtrack:get_sign(ld.x),
-						z = railtrack:get_sign(ld.z),
-						y = self.cart.dir.y
-					}
-				end
-			end
-			local pos = vector.round(self.object:getpos())
-			local dir = vector.round(vector.normalize(direction))
-			local speed = railcart:velocity_to_speed(self.cart.vel)
-			self.timer = 0
-			self.cart.target = nil
-			self.cart.prev = pos
-			self.cart.vel = vector.multiply(dir, 5)
-			self.cart.accel = railtrack:get_acceleration(pos)
-			self.object:setvelocity(self.cart.vel)
-		end
-	end,
-	on_rightclick = function(self, clicker)
-		if not is_valid_player(clicker) then
-			return
-		end
-		if clicker:get_player_control().sneak then
-			local name = clicker:get_player_name()
-			local cart = self.cart or {}
-			if cart.id and name then
-				local formspec = "size[8,9]"..
-					--default.gui_bg..default.gui_bg_img..default.gui_slots..
-					"list[detached:railcart_"..cart.id..";main;0,0.3;8,4;]"..
-					"list[current_player;main;0,4.85;8,1;]"..
-					"list[current_player;main;0,6.08;8,3;8]"..
-					"listring[detached:railcart_"..cart.id..";main]"..
-					"listring[current_player;main]"..
-					--default.get_hotbar_bg(0,4.85)
-				minetest.show_formspec(name, "inventory", formspec)
-			end
-			return
-		end
-		if self.driver and clicker == self.driver then
-			self.driver = nil
-			clicker:set_detach()
-		elseif not self.driver then
-			self.driver = clicker
-			clicker:set_attach(self.object, "", {x=0,y=5,z=0}, {x=0,y=0,z=0})
-		end
-	end,
-})
-
-minetest.register_craftitem("railcart:cart", {
-	description = "Railcart",
-	inventory_image = "railcart_side.png",
-	wield_image = "railcart_side.png",
-	on_place = function(itemstack, placer, pointed_thing)
-		local name = placer:get_player_name()
-		if not name or pointed_thing.type ~= "node" then
-			return
-		end
-		if not minetest.is_singleplayer() then
-			if not minetest.check_player_privs(name, {carts=true}) then
-				minetest.chat_send_player(name, "Requires carts privilege")
-				return
-			end
-		end
-		local pos = pointed_thing.under
-		if not railtrack:is_railnode(pos) then
-			return
-		end
-		local carts = railcart:get_carts_in_radius(pos, 0.9)
-		if #carts > 0 then
-			return
-		end
-		local id = railcart:get_new_id()
-		local ref = {
-			id = id,
-			inv = create_detached_inventory(id),
-			pos = vector.new(pos),
-			prev = vector.new(pos),
-			accel = railtrack:get_acceleration(pos),
-			dir = railcart:get_rail_direction(pos),
-		}
-		local cart = railcart.cart:new(ref)
-		table.insert(railcart.allcarts, cart)
-		railcart:save()
-		if not minetest.setting_getbool("creative_mode") then
-			itemstack:take_item()
-		end
-		return itemstack
-	end,
-})
-
-minetest.register_privilege("carts", "Player can pick-up and place carts.")
-
-minetest.register_craft({
-	output = "railcart:cart",
-	recipe = {
-		{"default:steel_ingot", "", "default:steel_ingot"},
-		{"default:steel_ingot", "", "default:steel_ingot"},
-		{"group:wood", "default:steel_ingot", "group:wood"},
-	},
-})
-
-minetest.register_on_shutdown(function()
-	railcart:save()
-end)
-

games/default/files/railcart/railcart.lua

@@ -1,444 +0,0 @@
-local ENTITY_UPDATE_TIME = 1
-local OBJECT_UPDATE_TIME = 5
-local OBJECT_SAVE_TIME = 10
-local RELOAD_DISTANCE = 32
-local SNAP_DISTANCE = 0.5
-local SPEED_MIN = 0.1
-local SPEED_MAX = 15
-
-railcart = {
-	timer = 0,
-	allcarts = {},
-	default_entity = {
-		physical = false,
-		collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},
-		visual = "mesh",
-		mesh = "railcart.b3d",
-		visual_size = {x=1, y=1},
-		textures = {"railcart.png"},
-		cart = nil,
-		driver = nil,
-		timer = 0,
-	},
-}
-
-railcart.cart = {
-	id = nil,
-	pos = nil,
-	target = nil,
-	prev = nil,
-	accel = nil,
-	inv = nil,
-	dir = {x=0, y=0, z=0},
-	vel = {x=0, y=0, z=0},
-	acc = {x=0, y=0, z=0},
-	timer = 0,
-	name = "railcart:cart_entity",
-}
-
-function railcart.cart:new(obj)
-	obj = obj or {}
-	setmetatable(obj, self)
-	self.__index = self
-	return obj
-end
-
-function railcart.cart:is_loaded()
-	for _, player in pairs(minetest.get_connected_players()) do
-		local pos = player:get_pos()
-		if pos then
-			local dist = railtrack:get_distance(pos, self.pos)
-			if dist <= RELOAD_DISTANCE then
-				return true
-			end
-		end
-	end
-	return false
-end
-
-function railcart.cart:on_step(dtime)
-	self.timer = self.timer - dtime
-	if self.timer > 0 then
-		return
-	end
-	self.timer = OBJECT_UPDATE_TIME
-	local entity = railcart:get_cart_entity(self.id)
-	if entity.object then
-		return
-	end
-	if self:is_loaded() then
-		local object = minetest.add_entity(self.pos, self.name)
-		if object then
-			entity = object:get_luaentity() or {}
-			entity.cart = self
-			object:setvelocity(self.vel)
-			object:set_acceleration(self.acc)
-		end
-	else
-		self.timer = railcart:update(self, self.timer)
-	end
-end
-
-function railcart:register_entity(name, def)
-	local ref = {}
-	for k, v in pairs(railcart.default_entity) do
-		ref[k] = def[k] or railtrack:copy(v)
-	end
-	ref.on_activate = function(self, staticdata, dtime_s)
-		if type(def.on_activate) == "function" then
-			def.on_activate(self, staticdata, dtime_s)
-		end
-		self.object:set_armor_groups({immortal=1})
-		if staticdata == "expired" then
-			self.object:remove()
-		end
-	end
-	ref.on_step = function(self, dtime)
-		if type(def.on_step) == "function" then
-			def.on_step(self, dtime)
-		end
-		local cart = self.cart
-		local object = self.object
-		if not cart or not object then
-			return
-		end
-		self.timer = self.timer - dtime
-		if self.timer > 0 then
-			return
-		end
-		self.timer = railcart:update(cart, ENTITY_UPDATE_TIME, object)
-		if type(def.on_update) == "function" then
-			def.on_update(self)
-		end
-	end
-	ref.get_staticdata = function(self)
-		if type(def.get_staticdata) == "function" then
-			def.get_staticdata(self)
-		end
-		if self.cart then
-			if self.cart:is_loaded() == false then
-				self.cart.timer = 0
-				self.object:remove()
-			end
-		end
-		return "expired"
-	end
-	for k, v in pairs(def) do
-		ref[k] = ref[k] or v
-	end
-	minetest.register_entity(name, ref)
-end
-
-function railcart:save()
-	local carts = {}
-	for id, cart in pairs(railcart.allcarts) do
-		local ref = {}
-		for k, v in pairs(cart) do
-			ref[k] = v
-		end
-		local inv = {}
-		if ref.inv then
-			local list = ref.inv:get_list("main")
-			for i, stack in ipairs(list) do
-			  inv[i] = stack:to_string()
-			end
-		end
-		ref.inv = inv
-		table.insert(carts, ref)
-	end
-	local output = io.open(minetest.get_worldpath().."/railcart.txt",'w')
-	if output then
-		output:write(minetest.serialize(carts))
-		io.close(output)
-	end
-end
-
-function railcart:remove_cart(id)
-	for i, cart in pairs(railcart.allcarts) do
-		if cart.id == id then
-			railcart.allcarts[i] = nil
-			railcart:save()
-			break
-		end
-	end
-end
-
-function railcart:get_rail_direction(pos)
-	local target = nil
-	local cons = railtrack:get_connections(pos)
-	local ymax = pos.y
-	for _, con in pairs(cons) do
-		if con.y >= ymax then
-			ymax = con.y
-			target = con
-		end
-	end
-	if target then
-		if #cons == 1 then
-			target.y = pos.y
-		end
-		return railtrack:get_direction(target, pos)
-	end
-	return {x=0, y=0, z=0}
-end
-
-function railcart:get_new_id()
-	local id = 0
-	for _, cart in pairs(railcart.allcarts) do
-		if cart.id > id then
-			id = cart.id
-		end
-	end
-	return id + 1
-end
-
-function railcart:get_cart_ref(id)
-	for _, cart in pairs(railcart.allcarts) do
-		if cart.id == id then
-			return cart
-		end
-	end
-end
-
-function railcart:get_cart_entity(id)
-	local cart_ref = {}
-	for _, ref in pairs(minetest.luaentities) do
-		if ref.cart then
-			if ref.cart.id == id then
-				cart_ref = ref
-				break
-			end
-		end
-	end
-	return cart_ref
-end
-
-function railcart:get_carts_in_radius(pos, rad)
-	local carts = {}
-	for _, cart in pairs(railcart.allcarts) do
-		local px = pos.x - cart.pos.x
-		local py = pos.y - cart.pos.y
-		local pz = pos.z - cart.pos.z
-		if (px * px) + (py * py) + (pz * pz) <= rad * rad then
-			table.insert(carts, cart)
-		end
-	end
-	return carts
-end
-
-function railcart:get_cart_in_sight(p1, p2)
-	local ref = nil
-	local dist = railtrack:get_distance(p1, p2) + 1
-	local dir = railtrack:get_direction(p2, p1)
-	local carts = railcart:get_carts_in_radius(p1, dist)
-	for _, cart in pairs(carts) do
-		if not vector.equals(p1, cart.pos) then
-			local dc = railtrack:get_direction(cart.pos, p1)
-			if vector.equals(dc, dir) then
-				local d = railtrack:get_distance(p1, cart.pos)
-				if d < dist then
-					dist = d
-					ref = cart
-				end
-			end
-		end
-	end
-	return ref
-end
-
-function railcart:get_delta_time(vel, acc, dist)
-	if vel > 0 then
-		if acc == 0 then
-			return dist / vel
-		end
-		local r = math.sqrt(vel * vel + 2 * acc * dist)
-		if r > 0 then
-			return (-vel + r) / acc
-		end
-	end
-	return 9999 --INF
-end
-
-function railcart:velocity_to_dir(v)
-	if math.abs(v.x) > math.abs(v.z) then
-		return {x=railtrack:get_sign(v.x), y=railtrack:get_sign(v.y), z=0}
-	else
-		return {x=0, y=railtrack:get_sign(v.y), z=railtrack:get_sign(v.z)}
-	end
-end
-
-function railcart:velocity_to_speed(vel)
-	local speed = math.max(math.abs(vel.x), math.abs(vel.z))
-	if speed < SPEED_MIN then
-		speed = 0
-	elseif speed > SPEED_MAX then
-		speed = SPEED_MAX
-	end
-	return speed
-end
-
-function railcart:get_target(pos, vel)
-	local meta = minetest.get_meta(vector.round(pos))
-	local dir = self:velocity_to_dir(vel)
-	local targets = {}
-	local rots = railtrack.rotations
-	local contype = meta:get_string("contype") or ""
-	local s_junc = meta:get_string("junctions") or ""
-	local s_cons = meta:get_string("connections") or ""
-	local s_rots = meta:get_string("rotations") or ""
-	if contype == "section" then
-		local junctions = minetest.deserialize(s_junc) or {}
-		for _, p in pairs(junctions) do
-			table.insert(targets, p)
-		end
-	else
-		local cons = minetest.deserialize(s_cons) or {}
-		for _, p in pairs(cons) do
-			table.insert(targets, p)
-		end
-		if s_rots ~= "" then
-			local fwd = false
-			for _, p in pairs(cons) do
-				if vector.equals(vector.add(pos, dir), p) then
-					fwd = true
-				end
-			end
-			if fwd == true or #cons == 1 then
-				rots = s_rots
-			end
-		end
-	end
-	local rotations = railtrack:get_rotations(rots, dir)
-	for _, r in ipairs(rotations) do
-		for _, t in pairs(targets) do
-			local d = railtrack:get_direction(t, pos)
-			if r.x == d.x and r.z == d.z then
-				return t
-			end
-		end
-	end
-end
-
-function railcart:update(cart, time, object)
-	if object then
-		cart.pos = object:getpos()
-		cart.vel = object:get_velocity()
-	end
-	if not cart.target then
-		cart.pos = vector.new(cart.prev)
-		cart.target = railcart:get_target(cart.pos, cart.vel)
-		if object then
-			object:moveto(cart.pos)
-		end
-	end
-	local speed = railcart:velocity_to_speed(cart.vel)
-	if cart.target then
-		cart.dir = railtrack:get_direction(cart.target, cart.pos)
-	else
-		speed = 0
-	end
-	if speed > SPEED_MIN then
-		local blocked = false
-		local cis = railcart:get_cart_in_sight(cart.pos, cart.target)
-		if cis then
-			if railcart:velocity_to_speed(cis.vel) == 0 then
-				cart.target = vector.subtract(cis.pos, cart.dir)
-				blocked = true
-			end
-		end
---[[
-		if object then
-			local p1 = vector.add(cart.pos, {x=0, y=1, z=0})
-			local p2 = vector.add(cart.target, {x=0, y=1, z=0})
-			if minetest.get_node_or_nil(p2) then
-				local los, bp = minetest.line_of_sight(p1, p2)
-				if los == false then
-					bp.y = bp.y - 1
-					cart.target = vector.subtract(bp, cart.dir)
-					blocked = true
-				end
-			end
-		end
-]]--
-		local d1 = railtrack:get_distance(cart.prev, cart.target)
-		local d2 = railtrack:get_distance(cart.prev, cart.pos)
-		local dist = d1 - d2
-		if dist > SNAP_DISTANCE then
-			local accel = railtrack.accel_flat
-			if cart.dir.y == -1 then
-				accel = railtrack.accel_down
-			elseif cart.dir.y == 1 then
-				accel = railtrack.accel_up
-			end
-			accel = cart.accel or accel
-			if object then
-				dist = math.max(dist - SNAP_DISTANCE, 0)
-			end
-			local dt = railcart:get_delta_time(speed, accel, dist)
-			if dt < time then
-				time = dt
-			end
-			local dp = speed * time + 0.5 * accel * time * time
-			local vf = speed + accel * time
-			if object then
-				if vf <= 0 then
-					speed = 0
-					accel = 0
-				end
-				cart.vel = vector.multiply(cart.dir, speed)
-				cart.acc = vector.multiply(cart.dir, accel)
-			elseif dp > 0 then
-				cart.vel = vector.multiply(cart.dir, vf)
-				cart.pos = vector.add(cart.pos, vector.multiply(cart.dir, dp))
-			end
-		else
-			if blocked and vector.equals(cart.target, cart.prev) then
-				cart.vel = {x=0, y=0, z=0}
-				cart.acc = {x=0, y=0, z=0}
-			else
-				cart.pos = vector.new(cart.target)
-				cart.prev = vector.new(cart.target)
-				cart.accel = railtrack:get_acceleration(cart.target)
-				cart.target = nil
-				return 0
-			end
-		end
-	else
-		cart.dir = railcart:get_rail_direction(cart.pos)
-		cart.vel = {x=0, y=0, z=0}
-		cart.acc = {x=0, y=0, z=0}
-	end
-	if object then
-		if cart.dir.y == -1 then
-			object:set_animation({x=1, y=1}, 1, 0)
-		elseif cart.dir.y == 1 then
-			object:set_animation({x=2, y=2}, 1, 0)
-		else
-			object:set_animation({x=0, y=0}, 1, 0)
-		end
-		if cart.dir.x < 0 then
-			object:setyaw(math.pi / 2)
-		elseif cart.dir.x > 0 then
-			object:setyaw(3 * math.pi / 2)
-		elseif cart.dir.z < 0 then
-			object:setyaw(math.pi)
-		elseif cart.dir.z > 0 then
-			object:setyaw(0)
-		end
-		object:setvelocity(cart.vel)
-		object:set_acceleration(cart.acc)
-	end
-	return time
-end
-
-minetest.register_globalstep(function(dtime)
-	for _, cart in pairs(railcart.allcarts) do
-		cart:on_step(dtime)
-	end
-	railcart.timer = railcart.timer + dtime
-	if railcart.timer > OBJECT_SAVE_TIME then
-		railcart:save()
-		railcart.timer = 0
-	end
-end)
-

games/default/files/railtrack/LICENSE.txt

@@ -1,14 +0,0 @@
-Minetest Mod - Railtrack [railtrack]
-====================================
-
-License Source Code: LGPL v2.1
-
-License of media (textures, sounds and models not otherwise specified): CC-0
-
-Authors of media files:
------------------------
-
-rarkenin:
-
-  cart_rail_*.png
-

games/default/files/railtrack/README.txt

@@ -1,72 +0,0 @@
-Minetest Mod - Railtrack [railtrack]
-====================================
-
-Minetest version: 0.4.13
-
-Depends: default
-
-Proof of concept rail networking system which enables rail-carts to travel
-through unloaded map chunks.
-
-Please note, this mod makes heavy use of metadata so that much of the processing
-gets done as tracks are laid, for this reason a 'rails' privilege is required in
-order to place rails when using multiplayer mode.
-
-Crafting
---------
-
-R = Rail [default:rail]
-F = Mese Crystal Fragment [default:mese_crystal_fragment]
-C = Coal Lump [default:coal_lump]
-D = Diamond [default:diamond]
-M = Mese Block [default:mese]
-
-Powered Rail: [railtrack:powerrail]
-
-By default these rails apply a positive acceleration during the time a cart
-remains on a given section of track. When used with the mesecons mod the rails
-will require power from a mesecon source to become active.
-
-+---+---+---+
-| R | F | R |
-+---+---+---+
-
-Braking Rail: [railtrack:brakerail]
-
-By default these rails apply a negative acceleration during the time a cart
-remains on a given section of track. When used with the mesecons mod the rails
-will require power from a mesecon source to become active.
-
-+---+---+---+
-| R | C | R |
-+---+---+---+
-
-Superconducting Rail: [railtrack:superrail]
-
-Zero friction rails that are easier to manage and are also a little less
-cpu-intensive by avoiding the use of square root calculations.
-
-+---+---+---+
-| R | D | R |
-+---+---+---+
-
-Switching Rail: [railtrack:switchrail]
-
-Currently depends on mesecons to do much other than provide a convenient, zero
-friction union to join long sections of superconducting rails.
-
-+---+---+---+
-| R | M | R |
-+---+---+---+
-
-Misc Items
-----------
-
-Rail Fixer: [railtrack:fixer]
-
-Only available in creative menu or with give(me) privileges.
-
-Rail Inspector [railtrack:inspector]
-
-Only available in creative menu or with give(me) privileges.
-

games/default/files/railtrack/depends.txt

@@ -1 +0,0 @@
-default

games/default/files/railtrack/init.lua

@@ -1,200 +0,0 @@
-local modpath = minetest.get_modpath(minetest.get_current_modname())
-
-dofile(modpath.."/railtrack.lua")
-
-railtrack:register_rail(":default:rail", {
-	description = "Rail",
-	tiles = {"default_rail.png", "default_rail_curved.png",
-		"default_rail_t_junction.png", "default_rail_crossing.png"},
-	railtype = "rail",
-})
-
-railtrack:register_rail("railtrack:superrail", {
-	description = "Superconducting Rail",
-	tiles = {"carts_rail_sup.png", "carts_rail_curved_sup.png",
-		"carts_rail_t_junction_sup.png", "carts_rail_crossing_sup.png"},
-	railtype = "superrail",
-	acceleration = 0,
-})
-
-railtrack:register_rail("railtrack:powerrail", {
-	description = "Powered Rail",
-	tiles = {"carts_rail_pwr.png", "carts_rail_curved_pwr.png",
-		"carts_rail_t_junction_pwr.png", "carts_rail_crossing_pwr.png"},
-	railtype = "powerrail",
-	acceleration = 4,
-	mesecons = {
-		effector = {
-			action_on = function(pos, node)
-				railtrack:set_acceleration(pos, 4)
-			end,
-			action_off = function(pos, node)
-				railtrack:set_acceleration(pos, nil)
-			end,
-		},
-	},
-})
-
-railtrack:register_rail("railtrack:brakerail", {
-	description = "Braking Rail",
-	tiles = {"carts_rail_brk.png", "carts_rail_curved_brk.png",
-		"carts_rail_t_junction_brk.png", "carts_rail_crossing_brk.png"},
-	railtype = "brakerail",
-	acceleration = -4,
-	mesecons = {
-		effector = {
-			action_on = function(pos, node)
-				railtrack:set_acceleration(pos, -4)
-			end,
-			action_off = function(pos, node)
-				railtrack:set_acceleration(pos, nil)
-			end,
-		},
-	},
-})
-
-railtrack:register_rail("railtrack:switchrail", {
-	description = "Switching Rail",
-	tiles = {"carts_rail_swt.png", "carts_rail_curved_swt.png",
-		"carts_rail_t_junction_swt.png", "carts_rail_crossing_swt.png"},
-	railtype = "switchrail",
-	acceleration = 0,
-	mesecons = {
-		effector = {
-			action_on = function(pos, node)
-				local meta = minetest.get_meta(pos)
-				meta:set_string("rotations", "RFLB")
-			end,
-			action_off = function(pos, node)
-				local meta = minetest.get_meta(pos)
-				meta:set_string("rotations", nil)
-			end,
-		},
-	},
-})
-
-minetest.register_privilege("rails", "Player can dig and place rails.")
-
-minetest.register_tool("railtrack:fixer", {
-	description = "Rail Fixer",
-	inventory_image = "railtrack_fixer.png",
-	wield_image = "railtrack_fixer.png",
-	on_use = function(itemstack, user, pointed_thing)
-		local pos = minetest.get_pointed_thing_position(pointed_thing, false)
-		local name = user:get_player_name()
-		if not pos or not name or pointed_thing.type ~= "node" then
-			return
-		end
-		if not railtrack:is_railnode(pos) then
-			minetest.chat_send_player(name, "Not a rail node!")
-			return
-		end
-		if not minetest.is_singleplayer() then
-			if not minetest.check_player_privs(name, {rails=true}) then
-				minetest.chat_send_player(name, "Requires rails privilege")
-				return
-			end
-		end
-		local node = minetest.get_node(pos)
-		if node then
-			minetest.remove_node(pos)
-			minetest.set_node(pos, node)
-			local def = minetest.registered_items[node.name] or {}
-			local itemstack = ItemStack(node.name)
-			if type(def.after_place_node) == "function" then
-				def.after_place_node(pos, user, itemstack)
-			end
-		end
-	end,
-})
-
-minetest.register_tool("railtrack:inspector", {
-	description = "Rail Inspector",
-	inventory_image = "railtrack_inspector.png",
-	wield_image = "railtrack_inspector.png",
-	on_use = function(itemstack, user, pointed_thing)
-		local name = user:get_player_name()
-		local pos = minetest.get_pointed_thing_position(pointed_thing, false)
-		if not name or not pos then
-			return
-		end
-		local node = minetest.get_node(pos) or {}
-		if not railtrack:is_railnode(pos) or not node.name then
-			minetest.chat_send_player(name, "Not a rail node!")
-			return
-		end
-		local ref = minetest.registered_items[node.name] or {}
-		local meta = minetest.get_meta(pos)
-		local form = ""
-		local size = 2.5
-		form = form.."label[0.5,0.5;POS: "..minetest.pos_to_string(pos).."]"
-		local railtype = ref.railtype or "NIL"
-		form = form.."label[0.5,1.0;RAILTYPE: "..railtype.."]"
-		local contype = meta:get_string("contype") or "NIL"
-		form = form.."label[0.5,1.5;CONTYPE: "..contype.."]"
-		local accel = meta:get_string("acceleration") or "NIL"
-		form = form.."label[0.5,2.0;ACCEL: "..accel.."]"
-		local s_junc = meta:get_string("junctions")
-		if s_junc then
-			local junctions = minetest.deserialize(s_junc)
-			if junctions then
-				form = form.."label[0.5,2.5;JUNCTIONS:]"
-				for i, p in ipairs(junctions) do
-					size = size + 0.5
-					form = form.."label[0.5,"..size..";#"..i.." "
-							..minetest.pos_to_string(p).."]"
-				end
-			end
-		end
-		local s_cons = meta:get_string("connections")
-		if s_cons then
-			local cons = minetest.deserialize(s_cons)
-			if cons then
-				size = size + 0.5
-				form = form.."label[0.5,"..size..";CONNECTIONS:]"
-				for i, p in pairs(cons) do
-					size = size + 0.5
-					form = form.."label[0.5,"..size..";#"..i.." "
-							..minetest.pos_to_string(p).."]"
-				end
-			end
-		end
-		local s_rots = meta:get_string("rotations")
-		if s_rots then
-			size = size + 0.5
-			form = form.."label[0.5,"..size..";ROTATIONS: "..s_rots.."]"
-		end
-		form = form.."button_exit[3.0,"..(size + 1)..";2,0.5;;Ok]"
-		form = "size[8,"..(size + 2).."]"..form
-		minetest.show_formspec(name, "info", form)
-	end,
-})
-
-minetest.register_craft({
-	output = "railtrack:powerrail 2",
-	recipe = {
-		{"default:rail", "default:mese_crystal_fragment", "default:rail"},
-	}
-})
-
-minetest.register_craft({
-	output = "railtrack:brakerail 2",
-	recipe = {
-		{"default:rail", "default:coal_lump", "default:rail"},
-	}
-})
-
-minetest.register_craft({
-	output = "railtrack:switchrail 2",
-	recipe = {
-		{"default:rail", "default:mese", "default:rail"},
-	}
-})
-
-minetest.register_craft({
-	output = "railtrack:superrail 2",
-	recipe = {
-		{"default:rail", "default:diamond", "default:rail"},
-	}
-})
-

games/default/files/railtrack/railtrack.lua

@@ -1,288 +0,0 @@
-local MAX_SECTION_LEN = 20
-
-railtrack = {
-	rotations = "FLR",
-	accel_flat = -0.5,
-	accel_up = -2,
-	accel_down = 2,
-}
-
-railtrack.default_rail = {
-	description = "Rail",
-	drawtype = "raillike",
-	tiles = {"default_rail.png", "default_rail_curved.png",
-		"default_rail_t_junction.png", "default_rail_crossing.png"},
-	paramtype = "light",
-	sunlight_propagates = true,
-	walkable = false,
-	is_ground_content = false,
-	selection_box = {
-		type = "fixed",
-		fixed = {-1/2, -1/2, -1/2, 1/2, -1/2+1/16, 1/2},
-	},
-	groups = {bendy = 2, dig_immediate = 2, attached_node = 1,
-		connect_to_raillike = minetest.raillike_group("rail")},
-	railtype = "rail",
-	after_place_node = function(pos, placer, itemstack)
-		local meta = minetest.get_meta(pos)
-		local def = itemstack:get_definition() or {}
-		if def.acceleration then
-			meta:set_string("acceleration", def.acceleration)
-		end
-		local junc = {}
-		local contype = meta:get_string("contype") or ""
-		local s_cons = meta:get_string("connections") or ""
-		if contype == "section" then
-			railtrack:limit_section_len(placer, pos, meta)
-		elseif s_cons ~= "" then
-			local cons = minetest.deserialize(s_cons)
-			for _, con in pairs(cons) do
-				if railtrack:limit_section_len(placer, con) then
-					break
-				end
-			end
-		end
-	end,
-	on_construct = function(pos)
-		railtrack:update_rails(pos)
-	end,
-	after_destruct = function(pos, oldnode)
-		local cons = railtrack:get_connections(pos)
-		for _, p in pairs(cons) do
-			railtrack:update_rails(p)
-		end
-	end,
-}
-
-function railtrack:copy(t)
-	if type(t) ~= "table" then
-		return t
-	end
-	local copy = {}
-	for k, v in pairs(t) do
-		copy[k] = v
-	end
-	return copy
-end
-
-function railtrack:register_rail(name, def)
-	local udef = {}
-	for k, v in pairs(railtrack.default_rail) do
-		if not def[k] then
-			def[k] = railtrack:copy(v)
-		end
-		udef[k] = railtrack:copy(def[k])
-	end
-	def.inventory_image = def.inventory_image or def.tiles[1]
-	def.wield_image = def.wield_image or def.tiles[1]
-	minetest.register_node(name, def)
-	udef.drop = name
-	udef.railtype = udef.railtype.."_union"
-	udef.groups.not_in_creative_inventory=1
-	minetest.register_node(name.."_union", udef)
-end
-
-function railtrack:limit_section_len(player, pos, meta)
-	meta = meta or minetest.get_meta(pos)
-	local contype = meta:get_string("contype") or ""
-	if contype == "section" then
-		local s_junc = meta:get_string("junctions") or ""
-		if s_junc ~= "" then
-			local junc = minetest.deserialize(s_junc)
-			if #junc == 2 then
-				local dist = railtrack:get_distance(junc[1], junc[2])
-				if dist > MAX_SECTION_LEN then
-					local node = minetest.get_node(pos) or {}
-					if node.name then
-						minetest.swap_node(pos, {name=node.name.."_union"})
-						railtrack:update_rails(pos)
-					end
-				end
-			end
-		end
-	end
-end
-
-function railtrack:is_railnode(pos)
-	local node = minetest.get_node(pos)
-	if node then
-		return minetest.get_item_group(node.name, "connect_to_raillike") > 0
-	end
-end
-
-function railtrack:get_sign(z)
-	if z == 0 then
-		return 0
-	else
-		return z / math.abs(z)
-	end
-end
-
-function railtrack:get_rotations(s_rots, dir)
-	local rots = {}
-	for i = 1, string.len(s_rots) do
-		local r = string.sub(s_rots, i, i)
-		local rot = nil
-		if r == "F" then
-			rot = {x=dir.x, z=dir.z}
-		elseif r == "L" then
-			rot = {x=-dir.z, z=dir.x}
-		elseif r == "R" then
-			rot = {x=dir.z, z=-dir.x}
-		elseif r == "B" then
-			rot = {x=-dir.x, z=-dir.z}
-		end
-		if rot then
-			table.insert(rots, rot)
-		end
-	end
-	return rots
-end
-
-function railtrack:get_acceleration(pos)
-	local meta = minetest.get_meta(pos)
-	local accel = meta:get_string("acceleration") or ""
-	if accel ~= "" then
-		return tonumber(accel)
-	end
-end
-
-function railtrack:get_direction(p1, p2)
-	local v = vector.subtract(p1, p2)
-	return {
-		x = railtrack:get_sign(v.x),
-		y = railtrack:get_sign(v.y),
-		z = railtrack:get_sign(v.z),
-	}
-end
-
-function railtrack:get_distance(p1, p2)
-	local dx = p1.x - p2.x
-	local dz = p1.z - p2.z
-	return math.abs(dx) + math.abs(dz)
-end
-
-
-function railtrack:get_railtype(pos)
-	local node = minetest.get_node(pos) or {}
-	if node.name then
-		local ref = minetest.registered_items[node.name] or {}
-		return ref.railtype
-	end
-end
-
-function railtrack:get_connection_type(pos, cons)
-	local railtype = railtrack:get_railtype(pos)
-	if #cons == 0 then
-		return "single"
-	elseif #cons == 1 then
-		return "junction"
-	elseif #cons == 2 then
-		if cons[1].x == cons[2].x or cons[1].z == cons[2].z then
-			if (cons[1].y == cons[2].y and cons[1].y == pos.y) or
-					(math.abs(cons[1].y - cons[2].y) == 2) then
-				if railtype == railtrack:get_railtype(cons[1]) and
-						railtype == railtrack:get_railtype(cons[2]) then
-					return "section"
-				end
-			end
-		end
-	end
-	return "junction"
-end
-
-function railtrack:get_connections(pos)
-	local connections = {}
-	for y = 1, -1, -1 do
-		for x = -1, 1 do
-			for z = -1, 1 do
-				if math.abs(x) ~= math.abs(z) then
-					local p = vector.add(pos, {x=x, y=y, z=z})
-					if railtrack:is_railnode(p) then
-						table.insert(connections, p)
-					end
-				end
-			end
-		end
-	end
-	return connections
-end
-
-function railtrack:get_junctions(pos, last_pos, junctions)
-	junctions = junctions or {}
-	local cons = railtrack:get_connections(pos)
-	local contype = railtrack:get_connection_type(pos, cons)
-	if contype == "junction" then
-		table.insert(junctions, pos)
-	elseif contype == "section" then
-		if last_pos then
-			for i, p in pairs(cons) do
-				if vector.equals(p, last_pos) then
-					cons[i] = nil
-				end
-			end
-		end
-		for _, p in pairs(cons) do
-			railtrack:get_junctions(p, pos, junctions)
-		end
-	end
-	return junctions
-end
-
-function railtrack:set_acceleration(pos, accel)
-	local meta = minetest.get_meta(pos)
-	local contype = meta:get_string("contype")
-	if contype == "section" then
-		local s_junc = meta:get_string("junctions") or ""
-		local junc = minetest.deserialize(s_junc) or {}
-		if #junc == 2 then
-			local p = vector.new(junc[2])
-			local dir = railtrack:get_direction(junc[1], junc[2])
-			local dist = railtrack:get_distance(junc[1], junc[2])
-			for i = 0, dist do
-				local m = minetest.get_meta(p)
-				if m then
-					m:set_string("acceleration", tostring(accel))
-				end
-				p = vector.add(dir, p)
-			end
-		end
-	else
-		meta:set_string("acceleration", tostring(accel))
-	end
-end
-
-function railtrack:update_rails(pos, last_pos, level)
-	local connections = {}
-	local junctions = {}
-	local meta = minetest.get_meta(pos)
-	local cons = railtrack:get_connections(pos)
-	local contype = railtrack:get_connection_type(pos, cons)
-	level = level or 0
-	for i, p in pairs(cons) do
-		connections[i] = p
-	end
-	if contype == "junction" then
-		level = level + 1
-	end
-	if contype == "section" or level < 2 then
-		if last_pos then
-			for i, p in pairs(cons) do
-				if vector.equals(p, last_pos) then
-					cons[i] = nil
-				end
-			end
-		end
-		for _, p in pairs(cons) do
-			railtrack:update_rails(p, pos, level)
-		end
-	end
-	if contype == "section" then
-		junctions = railtrack:get_junctions(pos)
-		connections = {}
-	end
-	meta:set_string("connections", minetest.serialize(connections))
-	meta:set_string("junctions", minetest.serialize(junctions))
-	meta:set_string("contype", contype)
-end
-