Major reorganization, start setup for trains

mods/ENTITIES/mcl_minecarts/carts/minecart.lua

@@ -0,0 +1,84 @@
+local modname = minetest.get_current_modname()
+local S = minetest.get_translator(modname)
+
+local function activate_normal_minecart(self)
+	detach_driver(self)
+
+	-- Detach passenger
+	if self._passenger then
+		local mob = self._passenger.object
+		mob:set_detach()
+	end
+end
+
+mcl_minecarts.register_minecart({
+	itemstring = "mcl_minecarts:minecart",
+	craft = {
+		output = "mcl_minecarts:minecart",
+		recipe = {
+			{"mcl_core:iron_ingot", "", "mcl_core:iron_ingot"},
+			{"mcl_core:iron_ingot", "mcl_core:iron_ingot", "mcl_core:iron_ingot"},
+		},
+	},
+	entity_id = "mcl_minecarts:minecart",
+	description = S("Minecart"),
+	tt_helop = S("Vehicle for fast travel on rails"),
+	long_descp = S("Minecarts can be used for a quick transportion on rails.") .. "\n" ..
+		S("Minecarts only ride on rails and always follow the tracks. At a T-junction with no straight way ahead, they turn left. The speed is affected by the rail type."),
+		S("You can place the minecart on rails. Right-click it to enter it. Punch it to get it moving.") .. "\n" ..
+		S("To obtain the minecart, punch it while holding down the sneak key.") .. "\n" ..
+		S("If it moves over a powered activator rail, you'll get ejected."),
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart.b3d",
+		textures = {"mcl_minecarts_minecart.png"},
+	},
+	icon = "mcl_minecarts_minecart_normal.png",
+	drop = {"mcl_minecarts:minecart"},
+	on_rightclick = function(self, clicker)
+		local name = clicker:get_player_name()
+		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
+			--detach_driver(self)
+		elseif not self._driver and not clicker:get_player_control().sneak then
+			self._driver = player_name
+			self._start_pos = self.object:get_pos()
+			mcl_player.player_attached[player_name] = true
+			clicker:set_attach(self.object, "", vector.new(1,-1.75,-2), vector.new(0,0,0))
+			mcl_player.player_attached[name] = true
+			minetest.after(0.2, function(name)
+				local player = minetest.get_player_by_name(name)
+				if player then
+					mcl_player.player_set_animation(player, "sit" , 30)
+					player:set_eye_offset(vector.new(0,-5.5,0), vector.new(0,-4,0))
+					mcl_title.set(clicker, "actionbar", {text=S("Sneak to dismount"), color="white", stay=60})
+				end
+			end, name)
+		end
+	end,
+	on_activate_by_rail = activate_normal_minecart,
+	_mcl_minecarts_on_step = function(self, dtime)
+		-- Grab mob
+		if math.random(1,20) > 15 and not self._passenger then
+			local mobsnear = minetest.get_objects_inside_radius(self.object:get_pos(), 1.3)
+			for n=1, #mobsnear do
+				local mob = mobsnear[n]
+				if mob then
+					local entity = mob:get_luaentity()
+					if entity and entity.is_mob then
+						self._passenger = entity
+						mob:set_attach(self.object, "", PASSENGER_ATTACH_POSITION, vector.zero())
+						break
+					end
+				end
+			end
+		elseif self._passenger then
+			local passenger_pos = self._passenger.object:get_pos()
+			if not passenger_pos then
+				self._passenger = nil
+			end
+		end
+	end
+})

mods/ENTITIES/mcl_minecarts/carts/with_chest.lua

@@ -0,0 +1,35 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname)
+local mod = mcl_minecarts
+local S = minetest.get_translator(modname)
+
+-- Minecart with Chest
+mcl_minecarts.register_minecart({
+	itemstring = "mcl_minecarts:chest_minecart",
+	craft = {
+		output = "mcl_minecarts:chest_minecart",
+		recipe = {
+			{"mcl_chests:chest"},
+			{"mcl_minecarts:minecart"},
+		},
+	},
+	entity_id = "mcl_minecarts:chest_minecart",
+	description = S("Minecart with Chest"),
+	tt_help = nil,
+	longdesc = nil,
+	usagehelp = nil,
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart_chest.b3d",
+		textures = {
+			"mcl_chests_normal.png",
+			"mcl_minecarts_minecart.png"
+		},
+	},
+	icon = "mcl_minecarts_minecart_chest.png",
+	drop = {"mcl_minecarts:minecart", "mcl_chests:chest"},
+	groups = { container = 1 },
+	on_rightclick = nil,
+	on_activate_by_rail = nil,
+	creative = true
+})
+mcl_entity_invs.register_inv("mcl_minecarts:chest_minecart","Minecart",27,false,true)

mods/ENTITIES/mcl_minecarts/carts/with_commandblock.lua

@@ -0,0 +1,64 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname)
+local mod = mcl_minecarts
+local S = minetest.get_translator(modname)
+
+function table_metadata(table)
+	return {
+		table = table,
+		set_string = function(self, key, value)
+			--print("set_string("..tostring(key)..", "..tostring(value)..")")
+			self.table[key] = tostring(value)
+		end,
+		get_string = function(self, key)
+			if self.table[key] then
+				return tostring(self.table[key])
+			end
+		end
+	}
+end
+
+-- Minecart with Command Block
+mod.register_minecart({
+	itemstring = "mcl_minecarts:command_block_minecart",
+	entity_id = "mcl_minecarts:command_block_minecart",
+	description = S("Minecart with Command Block"),
+	tt_help = nil,
+	loncdesc = nil,
+	usagehelp = nil,
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart_block.b3d",
+		textures = {
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"jeija_commandblock_off.png^[verticalframe:2:0",
+			"mcl_minecarts_minecart.png",
+		},
+	},
+	icon = "mcl_minecarts_minecart_command_block.png",
+	drop = {"mcl_minecarts:minecart"},
+	on_rightclick = function(self, clicker)
+		self._staticdata.meta = self._staticdata.meta or {}
+		local meta = table_metadata(self._staticdata.meta)
+
+		mesecon.commandblock.handle_rightclick(meta, clicker)
+	end,
+	_mcl_minecarts_on_place = function(self, placer)
+		-- Create a fake metadata object that stores into the cart's staticdata
+		self._staticdata.meta = self._staticdata.meta or {}
+		local meta = table_metadata(self._staticdata.meta)
+
+		mesecon.commandblock.initialize(meta)
+		mesecon.commandblock.place(meta, placer)
+	end,
+	on_activate_by_rail = function(self, timer)
+		self._staticdata.meta = self._staticdata.meta or {}
+		local meta = table_metadata(self._staticdata.meta)
+
+		mesecon.commandblock.action_on(meta, self.object:get_pos())
+	end,
+	creative = true
+})

mods/ENTITIES/mcl_minecarts/carts/with_furnace.lua

@@ -0,0 +1,92 @@
+local modname = minetest.get_current_modname()
+local S = minetest.get_translator(modname)
+
+-- Minecart with Furnace
+mcl_minecarts.register_minecart({
+	itemstring = "mcl_minecarts:furnace_minecart",
+	craft = {
+		output = "mcl_minecarts:furnace_minecart",
+		recipe = {
+			{"mcl_furnaces:furnace"},
+			{"mcl_minecarts:minecart"},
+		},
+	},
+	entity_id = "mcl_minecarts:furnace_minecart",
+	description = S("Minecart with Furnace"),
+	tt_help = nil,
+	longdesc = S("A minecart with furnace is a vehicle that travels on rails. It can propel itself with fuel."),
+	usagehelp = S("Place it on rails. If you give it some coal, the furnace will start burning for a long time and the minecart will be able to move itself. Punch it to get it moving.") .. "\n" ..
+		S("To obtain the minecart and furnace, punch them while holding down the sneak key."),
+
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart_block.b3d",
+		textures = {
+			"default_furnace_top.png",
+			"default_furnace_top.png",
+			"default_furnace_front.png",
+			"default_furnace_side.png",
+			"default_furnace_side.png",
+			"default_furnace_side.png",
+			"mcl_minecarts_minecart.png",
+		},
+	},
+	icon = "mcl_minecarts_minecart_furnace.png",
+	drop = {"mcl_minecarts:minecart", "mcl_furnaces:furnace"},
+	on_rightclick = function(self, clicker)
+		local staticdata = self._staticdata
+
+		-- Feed furnace with coal
+		if not clicker or not clicker:is_player() then
+			return
+		end
+		local held = clicker:get_wielded_item()
+		if minetest.get_item_group(held:get_name(), "coal") == 1 then
+			staticdata.fueltime = (staticdata.fueltime or 0) + 180
+
+			-- Trucate to 27 minutes (9 uses)
+			if staticdata.fueltime > 27*60 then
+				staticdata.fuel_time = 27*60
+			end
+
+			if not minetest.is_creative_enabled(clicker:get_player_name()) then
+				held:take_item()
+				local index = clicker:get_wield_index()
+				local inv = clicker:get_inventory()
+				inv:set_stack("main", index, held)
+			end
+			self.object:set_properties({textures =
+			{
+				"default_furnace_top.png",
+				"default_furnace_top.png",
+				"default_furnace_front_active.png",
+				"default_furnace_side.png",
+				"default_furnace_side.png",
+				"default_furnace_side.png",
+				"mcl_minecarts_minecart.png",
+			}})
+		end
+	end,
+	on_activate_by_rail = nil,
+	creative = true,
+	_mcl_minecarts_on_step = function(self, dtime)
+		local staticdata = self._staticdata
+
+		-- Update furnace stuff
+		if (staticdata.fueltime or 0) > 0 then
+			staticdata.fueltime = (staticdata.fueltime or dtime) - dtime
+			if staticdata.fueltime <= 0 then
+				self.object:set_properties({textures =
+					{
+					"default_furnace_top.png",
+					"default_furnace_top.png",
+					"default_furnace_front.png",
+					"default_furnace_side.png",
+					"default_furnace_side.png",
+					"default_furnace_side.png",
+					"mcl_minecarts_minecart.png",
+				}})
+				staticdata.fueltime = 0
+			end
+		end
+	end,
+})

mods/ENTITIES/mcl_minecarts/carts/with_hopper.lua

@@ -0,0 +1,178 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname)
+local mod = mcl_minecarts
+local S = minetest.get_translator(modname)
+
+local LOGGING_ON = minetest.settings:get_bool("mcl_logging_minecarts", false)
+local function mcl_log(message)
+	if LOGGING_ON then
+		mcl_util.mcl_log(message, "[Minecarts]", true)
+	end
+end
+
+local function hopper_take_item(self, dtime)
+	local pos = self.object:get_pos()
+	if not pos then return end
+
+	if not self or self.name ~= "mcl_minecarts:hopper_minecart" then return end
+
+	if mcl_util.check_dtime_timer(self, dtime, "hoppermc_take", 0.15) then
+		--minetest.log("The check timer was triggered: " .. dump(pos) .. ", name:" .. self.name)
+	else
+		--minetest.log("The check timer was not triggered")
+		return
+	end
+
+
+	local above_pos = vector.offset(pos, 0, 0.9, 0)
+	local objs = minetest.get_objects_inside_radius(above_pos, 1.25)
+
+	if objs then
+		mcl_log("there is an itemstring. Number of objs: ".. #objs)
+
+		for k, v in pairs(objs) do
+			local ent = v:get_luaentity()
+
+			if ent and not ent._removed and ent.itemstring and ent.itemstring ~= "" then
+				local taken_items = false
+
+				mcl_log("ent.name: " .. tostring(ent.name))
+				mcl_log("ent pos: " .. tostring(ent.object:get_pos()))
+
+				local inv = mcl_entity_invs.load_inv(self, 5)
+				if not inv then return false end
+
+				local current_itemstack = ItemStack(ent.itemstring)
+
+				mcl_log("inv. size: " .. self._inv_size)
+				if inv:room_for_item("main", current_itemstack) then
+					mcl_log("Room")
+					inv:add_item("main", current_itemstack)
+					ent.object:get_luaentity().itemstring = ""
+					ent.object:remove()
+					taken_items = true
+				else
+					mcl_log("no Room")
+				end
+
+				if not taken_items then
+					local items_remaining = current_itemstack:get_count()
+
+					-- This will take part of a floating item stack if no slot can hold the full amount
+					for i = 1, self._inv_size, 1 do
+						local stack = inv:get_stack("main", i)
+
+						mcl_log("i: " .. tostring(i))
+						mcl_log("Items remaining: " .. items_remaining)
+						mcl_log("Name: " .. tostring(stack:get_name()))
+
+						if current_itemstack:get_name() == stack:get_name() then
+							mcl_log("We have a match. Name: " .. tostring(stack:get_name()))
+
+							local room_for = stack:get_stack_max() - stack:get_count()
+							mcl_log("Room for: " .. tostring(room_for))
+
+							if room_for == 0 then
+								-- Do nothing
+								mcl_log("No room")
+							elseif room_for < items_remaining then
+								mcl_log("We have more items remaining than space")
+
+								items_remaining = items_remaining - room_for
+								stack:set_count(stack:get_stack_max())
+								inv:set_stack("main", i, stack)
+								taken_items = true
+							else
+								local new_stack_size = stack:get_count() + items_remaining
+								stack:set_count(new_stack_size)
+								mcl_log("We have more than enough space. Now holds: " .. new_stack_size)
+
+								inv:set_stack("main", i, stack)
+								items_remaining = 0
+
+								ent.object:get_luaentity().itemstring = ""
+								ent.object:remove()
+
+								taken_items = true
+								break
+							end
+
+							mcl_log("Count: " .. tostring(stack:get_count()))
+							mcl_log("stack max: " .. tostring(stack:get_stack_max()))
+							--mcl_log("Is it empty: " .. stack:to_string())
+						end
+
+						if i == self._inv_size and taken_items then
+							mcl_log("We are on last item and still have items left. Set final stack size: " .. items_remaining)
+							current_itemstack:set_count(items_remaining)
+							--mcl_log("Itemstack2: " .. current_itemstack:to_string())
+							ent.itemstring = current_itemstack:to_string()
+						end
+					end
+				end
+
+				--Add in, and delete
+				if taken_items then
+					mcl_log("Saving")
+					mcl_entity_invs.save_inv(ent)
+					return taken_items
+				else
+					mcl_log("No need to save")
+				end
+
+			end
+		end
+	end
+
+	return false
+end
+
+-- Minecart with Hopper
+mod.register_minecart({
+	itemstring = "mcl_minecarts:hopper_minecart",
+	craft = {
+		output = "mcl_minecarts:hopper_minecart",
+		recipe = {
+			{"mcl_hoppers:hopper"},
+			{"mcl_minecarts:minecart"},
+		},
+	},
+	entity_id = "mcl_minecarts:hopper_minecart",
+	description = S("Minecart with Hopper"),
+	tt_help = nil,
+	longdesc = nil,
+	usagehelp = nil,
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart_hopper.b3d",
+		textures = {
+			"mcl_hoppers_hopper_inside.png",
+			"mcl_minecarts_minecart.png",
+			"mcl_hoppers_hopper_outside.png",
+			"mcl_hoppers_hopper_top.png",
+		},
+	},
+	icon = "mcl_minecarts_minecart_hopper.png",
+	drop = {"mcl_minecarts:minecart", "mcl_hoppers:hopper"},
+	groups = { container = 1 },
+	on_rightclick = nil,
+	on_activate_by_rail = nil,
+	_mcl_minecarts_on_enter = function(self, pos)
+		local staticdata = self._staticdata
+		if (staticdata.hopper_delay or 0) > 0 then
+			return
+		end
+
+		-- try to pull from containers into our inventory
+		local inv = mcl_entity_invs.load_inv(self,5)
+		local above_pos = pos + vector.new(0,1,0)
+		mcl_util.hopper_pull_to_inventory(inv, 'main', above_pos, pos)
+
+		staticdata.hopper_delay =  (staticdata.hopper_delay or 0) + (1/20)
+	end,
+	_mcl_minecarts_on_step = function(self, dtime)
+		hopper_take_item(self, dtime)
+	end,
+	creative = true
+})
+mcl_entity_invs.register_inv("mcl_minecarts:hopper_minecart", "Hopper Minecart", 5, false, true)
+

mods/ENTITIES/mcl_minecarts/carts/with_tnt.lua

@@ -0,0 +1,123 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname)
+local mod = mcl_minecarts
+local S = minetest.get_translator(modname)
+
+-- Minecart with TNT
+local function activate_tnt_minecart(self, timer)
+	if self._boomtimer then
+		return
+	end
+	if timer then
+		self._boomtimer = timer
+	else
+		self._boomtimer = tnt.BOOMTIMER
+	end
+	self.object:set_properties({textures = {
+		"mcl_tnt_blink.png",
+		"mcl_tnt_blink.png",
+		"mcl_tnt_blink.png",
+		"mcl_tnt_blink.png",
+		"mcl_tnt_blink.png",
+		"mcl_tnt_blink.png",
+		"mcl_minecarts_minecart.png",
+	}})
+	self._blinktimer = tnt.BLINKTIMER
+	minetest.sound_play("tnt_ignite", {pos = self.object:get_pos(), gain = 1.0, max_hear_distance = 15}, true)
+end
+mod.register_minecart({
+	itemstring = "mcl_minecarts:tnt_minecart",
+	craft = {
+		output = "mcl_minecarts:tnt_minecart",
+		recipe = {
+			{"mcl_tnt:tnt"},
+			{"mcl_minecarts:minecart"},
+		},
+	},
+	entity_id = "mcl_minecarts:tnt_minecart",
+	description = S("Minecart with TNT"),
+	tt_help = S("Vehicle for fast travel on rails").."\n"..S("Can be ignited by tools or powered activator rail"),
+	longdesc = S("A minecart with TNT is an explosive vehicle that travels on rail."),
+	usagehelp = S("Place it on rails. Punch it to move it. The TNT is ignited with a flint and steel or when the minecart is on an powered activator rail.") .. "\n" ..
+		S("To obtain the minecart and TNT, punch them while holding down the sneak key. You can't do this if the TNT was ignited."),
+	initial_properties = {
+		mesh = "mcl_minecarts_minecart_block.b3d",
+		textures = {
+			"default_tnt_top.png",
+			"default_tnt_bottom.png",
+			"default_tnt_side.png",
+			"default_tnt_side.png",
+			"default_tnt_side.png",
+			"default_tnt_side.png",
+			"mcl_minecarts_minecart.png",
+		},
+	},
+	icon = "mcl_minecarts_minecart_tnt.png",
+	drop = {"mcl_minecarts:minecart", "mcl_tnt:tnt"},
+	on_rightclick = function(self, clicker)
+		-- Ingite
+		if not clicker or not clicker:is_player() then
+			return
+		end
+		if self._boomtimer then
+			return
+		end
+		local held = clicker:get_wielded_item()
+		if held:get_name() == "mcl_fire:flint_and_steel" then
+			if not minetest.is_creative_enabled(clicker:get_player_name()) then
+				held:add_wear(65535/65) -- 65 uses
+				local index = clicker:get_wield_index()
+				local inv = clicker:get_inventory()
+				inv:set_stack("main", index, held)
+			end
+			activate_tnt_minecart(self)
+		end
+	end,
+	on_activate_by_rail = activate_tnt_minecart,
+	creative = true,
+	_mcl_minecarts_on_step = function(self, dtime)
+		-- Update TNT stuff
+		if self._boomtimer then
+			-- Explode
+			self._boomtimer = self._boomtimer - dtime
+			local pos = self.object:get_pos()
+			if self._boomtimer <= 0 then
+				self.object:remove()
+				mcl_explosions.explode(pos, 6, { drop_chance = 1.0 })
+				return
+			else
+				tnt.smoke_step(pos)
+			end
+		end
+		if self._blinktimer then
+			self._blinktimer = self._blinktimer - dtime
+			if self._blinktimer <= 0 then
+				self._blink = not self._blink
+				if self._blink then
+					self.object:set_properties({textures =
+					{
+					"default_tnt_top.png",
+					"default_tnt_bottom.png",
+					"default_tnt_side.png",
+					"default_tnt_side.png",
+					"default_tnt_side.png",
+					"default_tnt_side.png",
+					"mcl_minecarts_minecart.png",
+					}})
+				else
+					self.object:set_properties({textures =
+					{
+					"mcl_tnt_blink.png",
+					"mcl_tnt_blink.png",
+					"mcl_tnt_blink.png",
+					"mcl_tnt_blink.png",
+					"mcl_tnt_blink.png",
+					"mcl_tnt_blink.png",
+					"mcl_minecarts_minecart.png",
+					}})
+				end
+				self._blinktimer = tnt.BLINKTIMER
+			end
+		end
+	end,
+})

mods/ENTITIES/mcl_minecarts/functions.lua

@@ -312,3 +312,48 @@ function mcl_minecarts:get_rail_direction(pos_, dir, ctrl, old_switch, railtype)
 
 	return dir
 end
+function mcl_minecarts:update_cart_orientation()
+	local staticdata = self._staticdata
+
+	-- constants
+	local _2_pi = math.pi * 2
+	local pi = math.pi
+	local dir = staticdata.dir
+
+	-- Calculate an angle from the x,z direction components
+	local rot_y = math.atan2( dir.x, dir.z ) + ( staticdata.rot_adjust or 0 )
+	if rot_y < 0 then
+		rot_y = rot_y + _2_pi
+	end
+
+	-- Check if the rotation is a 180 flip and don't change if so
+	local rot = self.object:get_rotation()
+	local diff = math.abs((rot_y - ( rot.y + pi ) % _2_pi) )
+	if diff < 0.001 or diff > _2_pi - 0.001 then
+		-- Update rotation adjust and recalculate the rotation
+		staticdata.rot_adjust = ( ( staticdata.rot_adjust or 0 ) + pi ) % _2_pi
+		rot.y = math.atan2( dir.x, dir.z ) + ( staticdata.rot_adjust or 0 )
+	else
+		rot.y = rot_y
+	end
+
+	-- Forward/backwards tilt (pitch)
+	if dir.y < 0 then
+		rot.x = -0.25 * pi
+	elseif dir.y > 0 then
+		rot.x = 0.25 * pi
+	else
+		rot.x = 0
+	end
+
+	if ( staticdata.rot_adjust or 0 ) < 0.01 then
+		rot.x = -rot.x
+	end
+	if dir.z ~= 0 then
+		rot.x = -rot.x
+	end
+
+	self.object:set_rotation(rot)
+end
+
+

mods/ENTITIES/mcl_minecarts/init.lua

@@ -1,11 +1,14 @@
 local modname = minetest.get_current_modname()
-
+local modpath = minetest.get_modpath(modname)
 mcl_minecarts = {}
 local mod = mcl_minecarts
-mcl_minecarts.modpath = minetest.get_modpath(modname)
+mcl_minecarts.modpath = modpath
+
+-- Constants
 mcl_minecarts.speed_max = 10
 mcl_minecarts.check_float_time = 15
+mcl_minecarts.FRICTION = 0.4
 
-dofile(mcl_minecarts.modpath.."/functions.lua")
+for _,filename in pairs({"functions","rails","train","storage","carts"}) do
-dofile(mcl_minecarts.modpath.."/rails.lua")
+	dofile(modpath.."/"..filename..".lua")
-dofile(mcl_minecarts.modpath.."/carts.lua")
+end

mods/ENTITIES/mcl_minecarts/movement.lua

@@ -0,0 +1,496 @@
+local modname = minetest.get_current_modname()
+local modpath = minetest.get_modpath(modname)
+local mod = mcl_minecarts
+local S = minetest.get_translator(modname)
+
+-- Constants
+local DEBUG = false
+local friction = mcl_minecarts.FRICTION
+
+-- Imports
+local train_length = mod.train_length
+local update_train = mod.update_train
+local update_cart_orientation = mod.update_cart_orientation
+local get_cart_data = mod.get_cart_data
+
+local function detach_minecart(self)
+	local staticdata = self._staticdata
+
+	staticdata.connected_at = nil
+	self.object:set_velocity(staticdata.dir * staticdata.velocity)
+end
+mod.detach_minecart = detach_minecart
+
+local function try_detach_minecart(self)
+	local staticdata = self._staticdata
+
+	local node = minetest.get_node(staticdata.connected_at)
+	if minetest.get_item_group(node.name, "rail") == 0 then
+		detach_minecart(self)
+	end
+end
+
+--[[
+	Array of hooks { {u,v,w}, name }
+	Actual position is pos + u * dir + v * right + w * up
+]]
+local enter_exit_checks = {
+	{ 0, 0, 0, "" },
+	{ 0, 0, 1, "_above" },
+	{ 0, 0,-1, "_below" },
+	{ 0, 1, 0, "_side" },
+	{ 0,-1, 0, "_side" },
+}
+
+local function handle_cart_enter_exit(self, pos, next_dir, event)
+	local staticdata = self._staticdata
+
+	local dir = staticdata.dir
+	local right = vector.new( dir.z, dir.y, -dir.x)
+	local up = vector.new(0,1,0)
+	for _,check in ipairs(enter_exit_checks) do
+		local check_pos = pos + dir * check[1] + right * check[2] + up * check[3]
+		local node = minetest.get_node(check_pos)
+		local node_def = minetest.registered_nodes[node.name]
+		if node_def then
+			-- node-specific hook
+			local hook_name = "_mcl_minecarts_"..event..check[4]
+			local hook = node_def[hook_name]
+			if hook then hook(check_pos, self, next_dir, pos) end
+
+			-- global minecart hook
+			hook = mcl_minecarts[event..check[4]]
+			if hook then hook(check_pos, self, next_dir, node_def) end
+		end
+	end
+
+	-- Handle cart-specific behaviors
+	local hook = self["_mcl_minecarts_"..event]
+	if hook then hook(self, pos) end
+end
+local function set_metadata_cart_status(pos, uuid, state)
+	local meta = minetest.get_meta(pos)
+	local carts = minetest.deserialize(meta:get_string("_mcl_minecarts_carts")) or {}
+	carts[uuid] = state
+	meta:set_string("_mcl_minecarts_carts", minetest.serialize(carts))
+end
+local function handle_cart_enter(self, pos, next_dir)
+	--print("entering "..tostring(pos))
+	set_metadata_cart_status(pos, self._staticdata.uuid, 1)
+	handle_cart_enter_exit(self, pos, next_dir, "on_enter" )
+end
+local function handle_cart_leave(self, pos, next_dir)
+	--print("leaving "..tostring(pos))
+	set_metadata_cart_status(pos, self._staticdata.uuid, nil)
+	handle_cart_enter_exit(self, pos, next_dir, "on_leave" )
+end
+local function handle_cart_node_watches(self, dtime)
+	local staticdata = self._staticdata
+	local watches = staticdata.node_watches or {}
+	local new_watches = {}
+	for _,node_pos in ipairs(watches) do
+		local node = minetest.get_node(node_pos)
+		local node_def = minetest.registered_nodes[node.name]
+		if node_def then
+			local hook = node_def._mcl_minecarts_node_on_step
+			if hook and hook(node_pos, self, dtime) then
+				new_watches[#new_watches+1] = node_pos
+			end
+		end
+	end
+
+	staticdata.node_watches = new_watches
+end
+
+local function handle_cart_collision(cart1, prev_pos, next_dir)
+	-- Look ahead one block
+	local pos = vector.add(prev_pos, next_dir)
+
+	local meta = minetest.get_meta(pos)
+	local carts = minetest.deserialize(meta:get_string("_mcl_minecarts_carts")) or {}
+	local cart_uuid = nil
+	local dirty = false
+	for uuid,v in pairs(carts) do
+		-- Clean up dead carts
+		if not get_cart_data(uuid) then
+			carts[uuid] = nil
+			dirty = true
+			uuid = nil
+		end
+
+		if uuid and uuid ~= cart1._staticdata.uuid then cart_uuid = uuid end
+	end
+	if dirty then
+		meta:set_string("_mcl_minecarts_carts",minetest.serialize(carts))
+	end
+
+	local meta = minetest.get_meta(vector.add(pos,next_dir))
+	if not cart_uuid then return end
+	minetest.log("action","cart #"..cart1._staticdata.uuid.." collided with cart #"..cart_uuid.." at "..tostring(pos))
+
+	local cart2_aoid = mcl_util.get_active_object_id_from_uuid(cart_uuid)
+	local cart2 = minetest.luaentities[cart2_aoid]
+	if not cart2 then return end
+
+	-- Standard Collision Handling
+	local cart1_staticdata = cart1._staticdata
+	local cart2_staticdata = cart2._staticdata
+
+	local u1 = cart1_staticdata.velocity
+	local u2 = cart2_staticdata.velocity
+	local m1 = cart1_staticdata.mass
+	local m2 = cart2_staticdata.mass
+
+	if u2 == 0 and u1 < 1 and train_length(cart1) < 3 then
+		-- Link carts
+		cart2_staticdata.behind = cart1_staticdata.uuid
+		cart1_staticdata.ahead = cart1_staticdata.uuid
+		cart2_staticdata.velocity = cart1_staticdata.velocity
+		return
+	end
+
+	-- Calculate new velocities according to https://en.wikipedia.org/wiki/Elastic_collision#One-dimensional_Newtonian
+	local c1 = m1 + m2
+	local d = m1 - m2
+	local v1 = (      d * u1 + 2 * m2 * u2 ) / c1
+	local v2 = ( 2 * m1 * u1 +      d * u2 ) / c1
+
+	cart1_staticdata.velocity = v1
+	cart2_staticdata.velocity = v2
+
+	-- Force the other cart to move the same direction this one was
+	cart2_staticdata.dir = mcl_minecarts:get_rail_direction(cart2_staticdata.connected_at, cart1_staticdata.dir)
+end
+
+
+local function vector_away_from_players(self, staticdata)
+	local objs = minetest.get_objects_inside_radius(self.object:get_pos(), 1.1)
+	for n=1,#objs do
+		local obj = objs[n]
+		local player_name = obj:get_player_name()
+		if player_name and player_name ~= "" and not ( self._driver and self._driver == player_name ) then
+			return obj:get_pos() - self.object:get_pos()
+		end
+	end
+
+	return nil
+end
+
+local function direction_away_from_players(self, staticdata)
+	local diff = vector_away_from_players(self, staticdata)
+	if not diff then return 0 end
+
+	local length = vector.distance(vector.new(0,0,0),diff)
+	local vec = diff / length
+	local force = vector.dot( vec, vector.normalize(staticdata.dir) )
+
+	-- Check if this would push past the end of the track and don't move it it would
+	-- This prevents an oscillation that would otherwise occur
+	local dir = staticdata.dir
+	if force > 0 then
+		dir = -dir
+	end
+	if mcl_minecarts:is_rail( staticdata.connected_at + dir ) then
+		if force > 0.5 then
+			return -length * 4
+		elseif force < -0.5 then
+			return length * 4
+		end
+	end
+	return 0
+end
+
+local function calculate_acceleration(self, staticdata)
+	local acceleration = 0
+
+	-- Fix up movement data
+	staticdata.velocity = staticdata.velocity or 0
+
+	-- Apply friction if moving
+	if staticdata.velocity > 0 then
+		acceleration = -friction
+	end
+
+	local pos = staticdata.connected_at
+	local node_name = minetest.get_node(pos).name
+	local node_def = minetest.registered_nodes[node_name]
+	local max_vel = mcl_minecarts.speed_max
+
+	if self._go_forward then
+		acceleration = 4
+	elseif self._brake then
+		acceleration = -1.5
+	elseif (staticdata.fueltime or 0) > 0 and staticdata.velocity <= 4 then
+		acceleration = 0.6
+	elseif staticdata.velocity >= ( node_def._max_acceleration_velocity or max_vel ) then
+		-- Standard friction
+	elseif node_def and node_def._rail_acceleration then
+		acceleration = node_def._rail_acceleration * 4
+	end
+
+	-- Factor in gravity after everything else
+	local gravity_strength = 2.45 --friction * 5
+	if staticdata.dir.y < 0 then
+		acceleration = gravity_strength - friction
+	elseif staticdata.dir.y > 0 then
+		acceleration = -gravity_strength + friction
+	end
+
+	return acceleration
+end
+
+local function reverse_direction(self, staticdata)
+	-- Complete moving thru this block into the next, reverse direction, and put us back at the same position we were at
+	local next_dir = -staticdata.dir
+	staticdata.connected_at = staticdata.connected_at + staticdata.dir
+	staticdata.distance = 1 - staticdata.distance
+
+	-- recalculate direction
+	local next_dir,_ = mcl_minecarts:get_rail_direction(staticdata.connected_at, next_dir, nil, nil, staticdata.railtype)
+	staticdata.dir = next_dir
+end
+
+local function do_movement_step(self, dtime)
+	local staticdata = self._staticdata
+	if not staticdata.connected_at then return 0 end
+
+	-- Calculate timestep remaiing in this block
+	local x_0 = staticdata.distance or 0
+	local remaining_in_block = 1 - x_0
+	local a = calculate_acceleration(self, staticdata)
+	local v_0 = staticdata.velocity
+
+	-- Repel minecarts
+	local away = direction_away_from_players(self, staticdata)
+	if away > 0 then
+		v_0 = away
+	elseif away < 0 then
+		reverse_direction(self, staticdata)
+		v_0 = -away
+	end
+
+	if DEBUG and ( v_0 > 0 or a ~= 0 ) then
+		print( "    cart "..tostring(staticdata.uuid)..
+		       ": a="..tostring(a)..
+		        ",v_0="..tostring(v_0)..
+		        ",x_0="..tostring(x_0)..
+		        ",timestep="..tostring(timestep)..
+		        ",dir="..tostring(staticdata.dir)..
+			",connected_at="..tostring(staticdata.connected_at)..
+			",distance="..tostring(staticdata.distance)
+		)
+	end
+
+	-- Not moving
+	if a == 0 and v_0 == 0 then return 0 end
+
+	-- Movement equation with acceleration: x_1 = x_0 + v_0 * t + 0.5 * a * t*t
+	local timestep
+	local stops_in_block = false
+	local inside = v_0 * v_0 + 2 * a * remaining_in_block
+	if inside < 0 then
+		-- Would stop or reverse direction inside this block, calculate time to v_1 = 0
+		timestep = -v_0 / a
+		stops_in_block = true
+	elseif a ~= 0 then
+		-- Setting x_1 = x_0 + remaining_in_block, and solving for t gives:
+		timestep = ( math.sqrt( v_0 * v_0 + 2 * a * remaining_in_block) - v_0 ) / a
+	else
+		timestep = remaining_in_block / v_0
+	end
+
+	-- Truncate timestep to remaining time delta
+	if timestep > dtime then
+		timestep = dtime
+	end
+
+	-- Truncate timestep to prevent v_1 from being larger that speed_max
+	local v_max = mcl_minecarts.speed_max
+	if (v_0 ~= v_max) and ( v_0 + a * timestep > v_max) then
+		timestep = ( v_max - v_0 ) / a
+	end
+
+	-- Prevent infinite loops
+	if timestep <= 0 then return 0 end
+
+	-- Calculate v_1 taking v_max into account
+	local v_1 = v_0 + a * timestep
+	if v_1 > v_max then
+		v_1 = v_max
+	elseif v_1 < friction / 5 then
+		v_1 = 0
+	end
+
+	-- Calculate x_1
+	local x_1 = x_0 + timestep * v_0 + 0.5 * a * timestep * timestep
+
+	-- Update position and velocity of the minecart
+	staticdata.velocity = v_1
+	staticdata.distance = x_1
+
+	if DEBUG and (1==0) and ( v_0 > 0 or a ~= 0 ) then
+		print( "-   cart #"..tostring(staticdata.uuid)..
+		       ": a="..tostring(a)..
+		        ",v_0="..tostring(v_0)..
+		        ",v_1="..tostring(v_1)..
+		        ",x_0="..tostring(x_0)..
+		        ",x_1="..tostring(x_1)..
+		        ",timestep="..tostring(timestep)..
+		        ",dir="..tostring(staticdata.dir)..
+			",connected_at="..tostring(staticdata.connected_at)..
+			",distance="..tostring(staticdata.distance)
+		)
+	end
+
+	-- Entity movement
+	local pos = staticdata.connected_at
+
+	-- Handle movement to next block, account for loss of precision in calculations
+	if x_1 >= 0.99 then
+		staticdata.distance = 0
+
+		-- Anchor at the next node
+		local old_pos = pos
+		pos = pos + staticdata.dir
+		staticdata.connected_at = pos
+
+		-- Get the next direction
+		local next_dir,_ = mcl_minecarts:get_rail_direction(pos, staticdata.dir, nil, nil, staticdata.railtype)
+		if DEBUG and next_dir ~= staticdata.dir then
+			print( "Changing direction from "..tostring(staticdata.dir).." to "..tostring(next_dir))
+		end
+
+		-- Handle cart collisions
+		handle_cart_collision(self, pos, next_dir)
+
+		-- Leave the old node
+		handle_cart_leave(self, old_pos, next_dir )
+
+		-- Enter the new node
+		handle_cart_enter(self, pos, next_dir)
+
+		try_detach_minecart(self)
+
+		-- Handle end of track
+		if next_dir == staticdata.dir * -1 and next_dir.y == 0 then
+			if DEBUG then print("Stopping cart at end of track at "..tostring(pos)) end
+			staticdata.velocity = 0
+		end
+
+		-- Update cart direction
+		staticdata.dir = next_dir
+	elseif stops_in_block and v_1 < (friction/5) and a <= 0 then
+		-- Handle direction flip due to gravity
+		if DEBUG then print("Gravity flipped direction") end
+
+		-- Velocity should be zero at this point
+		staticdata.velocity = 0
+
+		reverse_direction(self, staticdata)
+
+		-- Intermediate movement
+		pos = staticdata.connected_at + staticdata.dir * staticdata.distance
+	else
+		-- Intermediate movement
+		pos = pos + staticdata.dir * staticdata.distance
+	end
+
+	self.object:move_to(pos)
+
+	-- Update cart orientation
+	update_cart_orientation(self)
+
+	-- Debug reporting
+	if DEBUG and ( v_0 > 0 or v_1 > 0 ) then
+		print( "    cart #"..tostring(staticdata.uuid)..
+		       ": a="..tostring(a)..
+		        ",v_0="..tostring(v_0)..
+		        ",v_1="..tostring(v_1)..
+		        ",x_0="..tostring(x_0)..
+		        ",x_1="..tostring(x_1)..
+		        ",timestep="..tostring(timestep)..
+		        ",dir="..tostring(staticdata.dir)..
+			",pos="..tostring(pos)..
+			",connected_at="..tostring(staticdata.connected_at)..
+			",distance="..tostring(staticdata.distance)
+		)
+	end
+
+	-- Report the amount of time processed
+	return dtime - timestep
+end
+
+local function do_movement( self, dtime )
+	local staticdata = self._staticdata
+
+	-- Allow the carts to be delay for the rest of the world to react before moving again
+	if ( staticdata.delay or 0 ) > dtime then
+		staticdata.delay = staticdata.delay - dtime
+		return
+	else
+		staticdata.delay = 0
+	end
+
+	-- Break long movements at block boundaries to make it
+	-- it impossible to jump across gaps due to server lag
+	-- causing large timesteps
+	while dtime > 0 do
+		local new_dtime = do_movement_step(self, dtime)
+
+		update_train(self)
+
+		-- Handle node watches here in steps to prevent server lag from changing behavior
+		handle_cart_node_watches(self, dtime - new_dtime)
+
+		dtime = new_dtime
+	end
+end
+
+local function do_detached_movement(self, dtime)
+	local staticdata = self._staticdata
+
+	-- Make sure the object is still valid before trying to move it
+	if not self.object or not self.object:get_pos() then return end
+
+	-- Apply physics
+	if mcl_physics then
+		mcl_physics.apply_entity_environmental_physics(self)
+	else
+		-- Simple physics
+		local friction = self.object:get_velocity() or vector.new(0,0,0)
+		friction.y = 0
+
+		local accel = vector.new(0,-9.81,0) -- gravity
+		accel = vector.add(accel, vector.multiply(friction,-0.9))
+		self.object:set_acceleration(accel)
+	end
+
+	local away = vector_away_from_players(self, staticdata)
+	if away then
+		local v = self.object:get_velocity()
+		self.object:set_velocity(v - away)
+	end
+
+	-- Try to reconnect to rail
+	local pos_r = vector.round(self.object:get_pos())
+	local node = minetest.get_node(pos_r)
+	if minetest.get_item_group(node.name, "rail") ~= 0 then
+		staticdata.connected_at = pos_r
+		staticdata.railtype = node.name
+
+		local freebody_velocity = self.object:get_velocity()
+		staticdata.dir = mod:get_rail_direction(pos_r, mod.snap_direction(freebody_velocity))
+
+		-- Use vector projection to only keep the velocity in the new direction of movement on the rail
+		-- https://en.wikipedia.org/wiki/Vector_projection
+		staticdata.velocity = vector.dot(staticdata.dir,freebody_velocity)
+
+		-- Clear freebody movement
+		self.object:set_velocity(vector.new(0,0,0))
+		self.object:set_acceleration(vector.new(0,0,0))
+	end
+end
+
+--return do_movement, do_detatched_movement
+return do_movement,do_detached_movement,handle_cart_enter
+

mods/ENTITIES/mcl_minecarts/rails.lua

@@ -188,7 +188,7 @@ function mod.register_rail(itemstring, ndef)
 	if not ndef.inventory_image then ndef.inventory_image = ndef.tiles[1] end
 	if not ndef.wield_image then ndef.wield_image = ndef.tiles[1] end
 
-	print("registering rail "..itemstring.." with definition: "..dump(ndef))
+	--print("registering rail "..itemstring.." with definition: "..dump(ndef))
 
 	-- Make registrations
 	minetest.register_node(itemstring, ndef)

mods/ENTITIES/mcl_minecarts/storage.lua

@@ -0,0 +1,37 @@
+local storage = minetest.get_mod_storage()
+local mod = mcl_minecarts
+
+local cart_data = {}
+local cart_data_fail_cache = {}
+
+function mod.get_cart_data(uuid)
+	if cart_data[uuid] then return cart_data[uuid] end
+	if cart_data_fail_cache[uuid] then return nil end
+
+	local data = minetest.deserialize(storage:get_string("cart-"..uuid))
+	if not data then
+		cart_data_fail_cache[uuid] = true
+		return nil
+	end
+
+	cart_data[uuid] = data
+	return data
+end
+local function save_cart_data(uuid)
+	if not cart_data[uuid] then return end
+	storage:set_string("cart-"..uuid,minetest.serialize(cart_data[uuid]))
+end
+mod.save_cart_data = save_cart_data
+
+function mod.update_cart_data(data)
+	local uuid = data.uuid
+	cart_data[uuid] = data
+	cart_data_fail_cache[uuid] = nil
+	save_cart_data(uuid)
+end
+function mod.destroy_cart_data(uuid)
+	storage:set_string("cart-"..uuid,"")
+	cart_data[uuid] = nil
+	cart_data_fail_cache[uuid] = true
+end
+

mods/ENTITIES/mcl_minecarts/train.lua

@@ -0,0 +1,5 @@
+function mcl_minecarts.update_train(cart)
+end
+
+function mcl_minecarts.train_length(cart)
+end