Add digits letters and make the code more generic (#10)

Updated luacheck version
LuaDoc comments for public functions

.github/workflows/luacheck.yml

@@ -5,6 +5,4 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master
-      - uses: Roang-zero1/factorio-mod-luacheck@master
-        with:
-          luacheckrc_url: ""
+      - uses: lunarmodules/luacheck@v0

.luacheckrc

@@ -1,5 +1,5 @@
 max_line_length = 180
-unused_args = false
+unused_args = true
 
 globals = {
 	"letters"

init.lua

@@ -1,189 +1,103 @@
-letters = {
-	{"al", "au", "a", "A"},
-	{"bl", "bu", "b", "B"},
-	{"cl", "cu", "c", "C"},
-	{"dl", "du", "d", "D"},
-	{"el", "eu", "e", "E"},
-	{"fl", "fu", "f", "F"},
-	{"gl", "gu", "g", "G"},
-	{"hl", "hu", "h", "H"},
-	{"il", "iu", "i", "I"},
-	{"jl", "ju", "j", "J"},
-	{"kl", "ku", "k", "K"},
-	{"ll", "lu", "l", "L"},
-	{"ml", "mu", "m", "M"},
-	{"nl", "nu", "n", "N"},
-	{"ol", "ou", "o", "O"},
-	{"pl", "pu", "p", "P"},
-	{"ql", "qu", "q", "Q"},
-	{"rl", "ru", "r", "R"},
-	{"sl", "su", "s", "S"},
-	{"tl", "tu", "t", "T"},
-	{"ul", "uu", "u", "U"},
-	{"vl", "vu", "v", "V"},
-	{"wl", "wu", "w", "W"},
-	{"xl", "xu", "x", "X"},
-	{"yl", "yu", "y", "Y"},
-	{"zl", "zu", "z", "Z"},
-}
+letters = {}
 
-local letters_reversed = {}
-
-for i, t in ipairs(letters) do
-	letters_reversed[t[3]] = i
-end
+local lettersmod = minetest.get_current_modname()
+local letterspath = minetest.get_modpath(lettersmod)
 
 local letter_cutter = {}
 letter_cutter.known_nodes = {}
 
+-- Use files in the textures folder to populate letter group tables.
+letter_cutter.names_upper = {}
+letter_cutter.names_lower = {}
+letter_cutter.names_digit = {}
+for _, tile in ipairs(minetest.get_dir_list(letterspath .. "/textures", false)) do
+	local char, group = tile:match("_([%d%u%l])(%l)_overlay")
+	if char and group then
+		if group == "d" then
+			table.insert(letter_cutter.names_digit, "letter_" ..char..group)
+		elseif group == "u" then
+			table.insert(letter_cutter.names_upper, "letter_" ..char..group)
+		elseif group == "l" then
+			table.insert(letter_cutter.names_lower, "letter_" ..char..group)
+		end
+	end
+end
+
 letter_cutter.show_item_list = dofile(
 	minetest.get_modpath(minetest.get_current_modname())..'/itemlist.lua')
 
-function letters.register_letters(modname, subname, from_node, description, tiles, def)
-
-	def = def and table.copy(def) or {}
+--- Register a node for use as a material in letter cutters.
+-- @param modname is the mod that the node belongs to.
+-- @param subname is the actual name of the node.
+-- @param from_node is the node that the letters will be crafted from (Usually modname:subname).
+-- @param description is the description of the node.
+-- @param tiles defines the image that will be used with the node.
+-- @param basedef (optional) may contain additional node definition parameters. Some might be overwritten to make the letters look and work as intended.
+function letters.register_letters(modname, subname, from_node, description, tiles, basedef)
+	basedef = basedef and table.copy(basedef) or {}
 
 	--default node
-	def.drawtype = "signlike"
-	def.paramtype = "light"
-	def.paramtype2 = def.paramtype2 or "wallmounted"
-	def.sunlight_propagates = true
-	def.is_ground_content = false
-	def.walkable = false
-	def.selection_box = {
+	basedef.drawtype = "signlike"
+	basedef.paramtype = "light"
+	basedef.paramtype2 = basedef.paramtype2 or "wallmounted"
+	basedef.sunlight_propagates = true
+	basedef.is_ground_content = false
+	basedef.walkable = false
+	basedef.selection_box = {
 		type = "wallmounted"
 		--wall_top = <default>
 		--wall_bottom = <default>
 		--wall_side = <default>
 	}
-	def.groups = def.groups or {
+	basedef.groups = basedef.groups or {
 		not_in_creative_inventory = 1,
 		not_in_craft_guide = 1,
 		oddly_breakable_by_hand = 1,
 		attached_node = 1
 	}
-	def.legacy_wallmounted = false
+	basedef.legacy_wallmounted = false
 
+	-- Register a new node for each letter using the provided from_node as the material.
+	for _, tile in ipairs(minetest.get_dir_list(letterspath .. "/textures", false)) do
+		local char, group = tile:match("_([%d%u%l])(%l)_overlay")
+		if char and group then
+			local def = table.copy(basedef)
 
-	for _, row in ipairs(letters) do
+			if group == "d" then
+				def.description = description.. " " ..char
+			elseif group == "u" then
+				def.description = description.. " " ..char:upper()
+			elseif group == "l" then
+				def.description = description.. " " ..char
+			end
+			def.inventory_image = tiles.. "^" ..tile.. "^[makealpha:255,126,126"
+			def.wield_image = def.inventory_image
+			def.tiles = {def.inventory_image}
 
-		def = table.copy(def)
-		def.description = description.. " " ..row[3]
-		def.inventory_image = tiles.. "^letters_" ..row[1].. "_overlay.png^[makealpha:255,126,126"
-		def.wield_image = def.inventory_image
-		def.tiles = {def.inventory_image}
-
-		minetest.register_node(":" ..modname..":"..subname.. "_letter_" ..row[1],def)
-
-		def = table.copy(def)
-		def.description = description.. " " ..row[4]
-		def.inventory_image = tiles.. "^letters_" ..row[2].. "_overlay.png^[makealpha:255,126,126"
-		def.wield_image = def.inventory_image
-		def.tiles = {def.inventory_image}
-
-		minetest.register_node(":" ..modname..":"..subname.. "_letter_" ..row[2], def)
-
-		--[[minetest.register_craft({
-			output = from_node,
-			recipe = {
-				{modname..":"..name, modname..":"..name, modname..":"..name},
-				{modname..":"..name, modname..":"..name, modname..":"..name},
-				{modname..":"..name, modname..":"..name, modname..":"..name},
-			},
-		})--]]
+			minetest.register_node(":" ..modname..":"..subname.. "_letter_" ..char..group,def)
+		end
 	end
 	letter_cutter.known_nodes[from_node] = {modname, subname}
 end
 
 local cost = 0.110
 
-letter_cutter.names_lower = {
-	{"letter_al"},
-	{"letter_bl"},
-	{"letter_cl"},
-	{"letter_dl"},
-	{"letter_el"},
-	{"letter_fl"},
-	{"letter_gl"},
-	{"letter_hl"},
-	{"letter_il"},
-	{"letter_jl"},
-	{"letter_kl"},
-	{"letter_ll"},
-	{"letter_ml"},
-	{"letter_nl"},
-	{"letter_ol"},
-	{"letter_pl"},
-	{"letter_ql"},
-	{"letter_rl"},
-	{"letter_sl"},
-	{"letter_tl"},
-	{"letter_ul"},
-	{"letter_vl"},
-	{"letter_wl"},
-	{"letter_xl"},
-	{"letter_yl"},
-	{"letter_zl"},
-}
-
-letter_cutter.names_upper = {
-	{"letter_au"},
-	{"letter_bu"},
-	{"letter_cu"},
-	{"letter_du"},
-	{"letter_eu"},
-	{"letter_fu"},
-	{"letter_gu"},
-	{"letter_hu"},
-	{"letter_iu"},
-	{"letter_ju"},
-	{"letter_ku"},
-	{"letter_lu"},
-	{"letter_mu"},
-	{"letter_nu"},
-	{"letter_ou"},
-	{"letter_pu"},
-	{"letter_qu"},
-	{"letter_ru"},
-	{"letter_su"},
-	{"letter_tu"},
-	{"letter_uu"},
-	{"letter_vu"},
-	{"letter_wu"},
-	{"letter_xu"},
-	{"letter_yu"},
-	{"letter_zu"},
-}
-
-function letter_cutter:get_output_inv_lower(modname, subname, amount, max)
-
+-- Collect items to display in letter cutter output inventory.
+function letter_cutter.get_output_inv(modname, subname, amount, max, group)
 	local list = {}
 	if amount < 1 then
 		return list
 	end
 
-	for i, t in ipairs(letter_cutter.names_lower) do
-		table.insert(list, modname .. ":" .. subname .. "_" .. t[1]
+	for _, name in ipairs(group) do
+		table.insert(list, modname .. ":" .. subname .. "_" .. name
 			.. " " .. math.min(math.floor(amount/cost), max))
 	end
 	return list
 end
 
-function letter_cutter:get_output_inv_upper(modname, subname, amount, max)
-
-	local list = {}
-	if amount < 1 then
-		return list
-	end
-
-	for i, t in ipairs(letter_cutter.names_upper) do
-		table.insert(list, modname .. ":" .. subname .. "_" .. t[1]
-			.. " " .. math.min(math.floor(amount/cost), max))
-	end
-	return list
-end
-
-function letter_cutter:reset_lower(pos)
+-- Reset letter cutter to its empty state.
+function letter_cutter:reset(pos)
 	local meta = minetest.get_meta(pos)
 	local inv  = meta:get_inventory()
 
@@ -191,38 +105,28 @@ function letter_cutter:reset_lower(pos)
 	inv:set_list("output", {})
 	meta:set_int("anz", 0)
 
+	local groupname = self.group_name(pos)
 	meta:set_string("infotext",
-			"Letter Cutter (Lower) is empty (owned by "..
+			"Letter Cutter ("..groupname..") is empty (owned by "..
 				meta:get_string("owner")..")")
 end
 
-function letter_cutter:reset_upper(pos)
-	local meta = minetest.get_meta(pos)
-	local inv  = meta:get_inventory()
-
-	inv:set_list("input",  {})
-	inv:set_list("output", {})
-	meta:set_int("anz", 0)
-
-	meta:set_string("infotext",
-			"Letter Cutter (Upper) is empty (owned by "..
-				meta:get_string("owner")..")")
-end
-
-function letter_cutter:update_inventory_lower(pos, amount)
+-- Update letter cutter inventories with available material count.
+function letter_cutter:update_inventory(pos, amount)
 	local meta          = minetest.get_meta(pos)
 	local inv           = meta:get_inventory()
 
 	amount = meta:get_int("anz") + amount
 
+	local groupname = self.group_name(pos)
 	if amount < 1 then -- If the last block is taken out.
-		self:reset_lower(pos)
+		self:reset(pos)
 		return
 	end
 
 	local stack = inv:get_stack("input",  1)
 	if stack:is_empty() then
-		self:reset_lower(pos)
+		self:reset(pos)
 		return
 
 	end
@@ -235,66 +139,32 @@ function letter_cutter:update_inventory_lower(pos, amount)
 		node_name.. " " .. math.floor(amount)
 	})
 
+	local max_offered = meta:get_int("max_offered")
+	local output = self.get_output_inv(modname, material, amount, max_offered, self.group(pos))
 	-- Display:
-	inv:set_list("output",
-		self:get_output_inv_lower(modname, material, amount,
-				meta:get_int("max_offered")))
+	inv:set_list("output", output)
 	-- Store how many microblocks are available:
 	meta:set_int("anz", amount)
 
 	meta:set_string("infotext",
-			"Letter Cutter (Lower) is working (owned by "..
+			"Letter Cutter ("..groupname..") is working (owned by "..
 				meta:get_string("owner")..")")
 end
 
-function letter_cutter:update_inventory_upper(pos, amount)
-	local meta          = minetest.get_meta(pos)
-	local inv           = meta:get_inventory()
-
-	amount = meta:get_int("anz") + amount
-
-	if amount < 1 then -- If the last block is taken out.
-		self:reset_upper(pos)
-		return
-	end
-
-	local stack = inv:get_stack("input",  1)
-	if stack:is_empty() then
-		self:reset_upper(pos)
-		return
-
-	end
-	local node_name = stack:get_name() or ""
-	local name_parts = letter_cutter.known_nodes[node_name] or ""
-	local modname  = name_parts[1] or ""
-	local material = name_parts[2] or ""
-
-	inv:set_list("input", {
-		node_name.. " " .. math.floor(amount)
-	})
-
-	-- Display:
-	inv:set_list("output",
-		self:get_output_inv_upper(modname, material, amount,
-				meta:get_int("max_offered")))
-	-- Store how many microblocks are available:
-	meta:set_int("anz", amount)
-
-	meta:set_string("infotext",
-			"Letter Cutter (Upper) is working (owned by "..
-				meta:get_string("owner")..")")
-end
-
-
-function letter_cutter.allow_metadata_inventory_move(
-		pos, from_list, from_index, to_list, to_index, count, player)
+-- Implement allow_metadata_inventory_move.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Moving is forbidden.
+function letter_cutter.allow_metadata_inventory_move(_pos, _from_list, _from_index, _to_list, _to_index, _count, _player)
 	return 0
 end
 
 
+-- Implement allow_metadata_inventory_put.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
 -- Only input- and recycle-slot are intended as input slots:
-function letter_cutter.allow_metadata_inventory_put(
-		pos, listname, index, stack, player)
+function letter_cutter.allow_metadata_inventory_put(pos, listname, index, stack, _player)
 	-- The player is not allowed to put something in there:
 	if listname == "output" then
 		return 0
@@ -311,7 +181,7 @@ function letter_cutter.allow_metadata_inventory_put(
 				inv:get_stack("input", index):get_name() ~= stackname then
 			return 0
 		end
-		for name, t in pairs(letter_cutter.known_nodes) do
+		for name, _ in pairs(letter_cutter.known_nodes) do
 			if name == stackname and inv:room_for_item("input", stack) then
 				return count
 			end
@@ -320,64 +190,70 @@ function letter_cutter.allow_metadata_inventory_put(
 	end
 end
 
-function letter_cutter.on_metadata_inventory_put_lower(
-		pos, listname, index, stack, player)
+-- Implement on_metadata_inventory_put.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Add craftable letters to the letter cutter inventory.
+function letter_cutter.on_metadata_inventory_put(pos, listname, _index, stack, _player)
 	local count = stack:get_count()
 
 	if listname == "input" then
-		letter_cutter:update_inventory_lower(pos, count)
+		letter_cutter:update_inventory(pos, count)
 	end
 end
 
-function letter_cutter.on_metadata_inventory_put_upper(
-		pos, listname, index, stack, player)
-	local count = stack:get_count()
-
-	if listname == "input" then
-		letter_cutter:update_inventory_upper(pos, count)
-	end
-end
-
-function letter_cutter.on_metadata_inventory_take_lower(
-		pos, listname, index, stack, player)
+-- Implement on_metadata_inventory_take.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Taking is allowed from all slots (even the internal microblock slot).
+function letter_cutter.on_metadata_inventory_take(pos, listname, _index, stack, _player)
 	if listname == "output" then
 		-- We do know how much each block at each position costs:
-		letter_cutter:update_inventory_lower(pos, 8 * -cost)
+		letter_cutter:update_inventory(pos, 8 * -cost)
 	elseif listname == "input" then
 		-- Each normal (= full) block taken costs 8 microblocks:
-		letter_cutter:update_inventory_lower(pos, 8 * -stack:get_count())
+		letter_cutter:update_inventory(pos, 8 * -stack:get_count())
 	end
 	-- The recycle field plays no role here since it is processed immediately.
 end
 
-function letter_cutter.on_metadata_inventory_take_upper(
-		pos, listname, index, stack, player)
-	if listname == "output" then
-		-- We do know how much each block at each position costs:
-		letter_cutter:update_inventory_upper(pos, 8 * -cost)
-	elseif listname == "input" then
-		-- Each normal (= full) block taken costs 8 microblocks:
-		letter_cutter:update_inventory_upper(pos, 8 * -stack:get_count())
-	end
-	-- The recycle field plays no role here since it is processed immediately.
-end
-
-function letter_cutter.remove_from_input(pos, origname, count)
+-- The name of the group of letters managed by this letter cutter.
+function letter_cutter.group_name(pos)
 	local node = minetest.get_node(pos)
+	if node.name == "letters:letter_cutter_digit" then
+		return "Digit"
+	elseif node.name == "letters:letter_cutter_upper" then
+		return "Upper"
+	elseif node.name == "letters:letter_cutter_lower" then
+		return "Lower"
+	end
+end
+
+-- The group of letters managed by this letter cutter.
+function letter_cutter.group(pos)
+	local node = minetest.get_node(pos)
+	if node.name == "letters:letter_cutter_digit" then
+		return letter_cutter.names_digit
+	elseif node.name == "letters:letter_cutter_upper" then
+		return letter_cutter.names_upper
+	elseif node.name == "letters:letter_cutter_lower" then
+		return letter_cutter.names_lower
+	end
+end
+
+-- Consume the input material and update inventories.
+function letter_cutter.remove_from_input(pos, origname, count)
 	local meta = minetest.get_meta(pos)
 
 	local cutterinv = meta:get_inventory()
 
 	local removed = cutterinv:remove_item("input", origname .. " " .. tostring(count))
-	if node.name == "letters:letter_cutter_upper" then
-		letter_cutter:update_inventory_upper(pos, -removed:get_count())
-	else
-		letter_cutter:update_inventory_lower(pos, -removed:get_count())
-	end
+	letter_cutter:update_inventory(pos, -removed:get_count())
 end
 
 local gui_slots = "listcolors[#606060AA;#808080;#101010;#202020;#FFF]"
 
+-- Update formspec.
 local function update_cutter_formspec(pos)
 	local meta = minetest.get_meta(pos)
 	meta:set_string("formspec", "size[11,9]" ..gui_slots..
@@ -391,6 +267,7 @@ local function update_cutter_formspec(pos)
 			"label[5.5,4.2;" .. minetest.formspec_escape(meta:get_string("message")) .. "]")
 end
 
+-- Create letter nodes from player-supplied text string.
 local function cut_from_text(pos, input_text, player)
 	local playername = player:get_player_name()
 
@@ -419,33 +296,41 @@ local function cut_from_text(pos, input_text, player)
 	throwawayinv:set_list("main", playerinv:get_list("main"))
 
 	for i = 1, #input_text do
+		-- Determine letter group.
 		local char = input_text:sub(i, i)
-
-		if char:match("[%u%l]") then
-			local isupper = char == char:upper()
-			local charset = isupper and letter_cutter.names_upper or letter_cutter.names_lower
-			local lettername = origname .. "_" .. charset[letters_reversed[char:lower()]][1]
-
-			if cuttercount < totalcost + cost then
-				meta:set_string("message", "Not enough materials.")
-				update_cutter_formspec(pos)
-
-				minetest.remove_detached_inventory("letter_cutter:throwaway")
-				return
-			end
-
-			if lettername and not throwawayinv:room_for_item("main", lettername) then
-				meta:set_string("message", "Not enough room.")
-				update_cutter_formspec(pos)
-
-				minetest.remove_detached_inventory("letter_cutter:throwaway")
-				return
-			end
-
-			totalcost = totalcost + cost
-
-			throwawayinv:add_item("main", lettername)
+		local group
+		if char:match("%d") then
+			group = "d"
+		elseif char:match("%u") then
+			group = "u"
+			char = char:lower()
+		elseif char:match("%l") then
+			group = "l"
+		else
+			goto continue -- unrecognized, skip it
 		end
+
+		local lettername = origname .. "_" .. "letter_" ..char:lower() ..group
+		if cuttercount < totalcost + cost then
+			meta:set_string("message", "Not enough materials.")
+			update_cutter_formspec(pos)
+
+			minetest.remove_detached_inventory("letter_cutter:throwaway")
+			return
+		end
+
+		if lettername and not throwawayinv:room_for_item("main", lettername) then
+			meta:set_string("message", "Not enough room.")
+			update_cutter_formspec(pos)
+
+			minetest.remove_detached_inventory("letter_cutter:throwaway")
+			return
+		end
+
+		totalcost = totalcost + cost
+
+		throwawayinv:add_item("main", lettername)
+		::continue::
 	end
 
 	meta:set_string("message", "Successfully added letters to inventory.")
@@ -457,13 +342,18 @@ local function cut_from_text(pos, input_text, player)
 	minetest.remove_detached_inventory("letter_cutter:throwaway")
 end
 
-function letter_cutter.on_construct_lower(pos)
+-- Implement on_construct.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Initialize a new letter cutter.
+function letter_cutter.on_construct(pos)
 	local meta = minetest.get_meta(pos)
+	local groupname = letter_cutter.group_name(pos)
 	update_cutter_formspec(pos)
 
 	meta:set_int("anz", 0) -- No microblocks inside yet.
 	meta:set_string("max_offered", 9) -- How many items of this kind are offered by default?
-	meta:set_string("infotext", "Letter Cutter (Lower) is empty")
+	meta:set_string("infotext", "Letter Cutter ("..groupname..") is empty")
 
 	meta:set_string("text", "")
 	meta:set_string("message", "")
@@ -472,29 +362,14 @@ function letter_cutter.on_construct_lower(pos)
 	inv:set_size("input", 1)    -- Input slot for full blocks of material x.
 	inv:set_size("output", 4*8) -- 4x8 versions of stair-parts of material x.
 
-	letter_cutter:reset_lower(pos)
+	letter_cutter:reset(pos)
 end
 
-function letter_cutter.on_construct_upper(pos)
-	local meta = minetest.get_meta(pos)
-	update_cutter_formspec(pos)
-
-	meta:set_int("anz", 0) -- No microblocks inside yet.
-	meta:set_string("max_offered", 9) -- How many items of this kind are offered by default?
-	meta:set_string("infotext", "Letter Cutter (Upper) is empty")
-
-	meta:set_string("text", "")
-	meta:set_string("message", "")
-
-	local inv = meta:get_inventory()
-	inv:set_size("input", 1)    -- Input slot for full blocks of material x.
-	inv:set_size("output", 4*8) -- 4x8 versions of stair-parts of material x.
-
-	letter_cutter:reset_upper(pos)
-end
-
-
-function letter_cutter.can_dig(pos,player)
+-- Implement can_dig.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Allow digging if the letter cutter is empty.
+function letter_cutter.can_dig(pos, _player)
 	local meta = minetest.get_meta(pos)
 	local inv = meta:get_inventory()
 	if not inv:is_empty("input") then
@@ -503,10 +378,14 @@ function letter_cutter.can_dig(pos,player)
 	return true
 end
 
-function letter_cutter.on_receive_fields(pos, formname, fields, sender)
+-- Implement on_receive_fields.
+-- https://minetest.gitlab.io/minetest/definition-tables/#node-definition
+--
+-- Handle formspec update.
+function letter_cutter.on_receive_fields(pos, _formname, fields, sender)
 	if fields.itemlist then
 		local list = {}
-		for name, t in pairs(letter_cutter.known_nodes) do
+		for name, _ in pairs(letter_cutter.known_nodes) do
 			list[#list+1] = name
 		end
 		letter_cutter.show_item_list(sender, 'Cuttable materials', list, pos)
@@ -525,20 +404,20 @@ minetest.register_node("letters:letter_cutter_lower",  {
 	node_box = {
 		type = "fixed",
 		fixed = {
-			{-0.4375, -0.5, -0.4375, -0.3125, 0.125, -0.3125}, -- NodeBox1
-			{-0.4375, -0.5, 0.3125, -0.3125, 0.125, 0.4375}, -- NodeBox2
-			{0.3125, -0.5, 0.3125, 0.4375, 0.125, 0.4375}, -- NodeBox3
-			{0.3125, -0.5, -0.4375, 0.4375, 0.125, -0.3125}, -- NodeBox4
-			{-0.5, 0.0625, -0.5, 0.5, 0.25, 0.5}, -- NodeBox5
-				{-0.125, 0.25, 0.125, 0.125, 0.3125, 0.1875}, -- NodeBox6
-			{0.125, 0.25, 0.0625, 0.1875, 0.3125, 0.125}, -- NodeBox7
-			{0.1875, 0.25, -0.1875, 0.25, 0.3125, 0.1875}, -- NodeBox8
-			{-0.1875, 0.25, 0.0625, -0.125, 0.3125, 0.125}, -- NodeBox9
-			{-0.25, 0.25, -0.1875, -0.1875, 0.3125, 0.0625}, -- NodeBox10
-			{-0.1875, 0.25, -0.25, -0.125, 0.3125, -0.1875}, -- NodeBox11
-			{-0.125, 0.25, -0.3125, 0.125, 0.3125, -0.25}, -- NodeBox12
-			{0.125, 0.25, -0.25, 0.375, 0.3125, -0.1875}, -- NodeBox13
-			{0.3125, 0.25, -0.1875, 0.375, 0.3125, -0.125}, -- NodeBox14
+			{-0.4375, -0.5, -0.4375, -0.3125, 0.125, -0.3125},
+			{-0.4375, -0.5, 0.3125, -0.3125, 0.125, 0.4375},
+			{0.3125, -0.5, 0.3125, 0.4375, 0.125, 0.4375},
+			{0.3125, -0.5, -0.4375, 0.4375, 0.125, -0.3125},
+			{-0.5, 0.0625, -0.5, 0.5, 0.25, 0.5},
+			{-0.125, 0.25, 0.125, 0.125, 0.3125, 0.1875},
+			{0.125, 0.25, 0.0625, 0.1875, 0.3125, 0.125},
+			{0.1875, 0.25, -0.1875, 0.25, 0.3125, 0.1875},
+			{-0.1875, 0.25, 0.0625, -0.125, 0.3125, 0.125},
+			{-0.25, 0.25, -0.1875, -0.1875, 0.3125, 0.0625},
+			{-0.1875, 0.25, -0.25, -0.125, 0.3125, -0.1875},
+			{-0.125, 0.25, -0.3125, 0.125, 0.3125, -0.25},
+			{0.125, 0.25, -0.25, 0.375, 0.3125, -0.1875},
+			{0.3125, 0.25, -0.1875, 0.375, 0.3125, -0.125},
 		},
 	},
 	tiles = {"letters_letter_cutter_lower_top.png",
@@ -549,9 +428,9 @@ minetest.register_node("letters:letter_cutter_lower",  {
 	paramtype2 = "facedir",
 	groups = {choppy = 2,oddly_breakable_by_hand = 2},
 	sounds = default.node_sound_wood_defaults(),
-	on_construct = letter_cutter.on_construct_lower,
+	on_construct = letter_cutter.on_construct,
 	can_dig = letter_cutter.can_dig,
-	-- Set the owner of this circular saw.
+	-- Set the cutter type and owner.
 	after_place_node = function(pos, placer)
 		local meta = minetest.get_meta(pos)
 		local owner = placer and placer:get_player_name() or ""
@@ -561,12 +440,9 @@ minetest.register_node("letters:letter_cutter_lower",  {
 					..meta:get_string("owner")..")")
 	end,
 	allow_metadata_inventory_move = letter_cutter.allow_metadata_inventory_move,
-	-- Only input- and recycle-slot are intended as input slots:
 	allow_metadata_inventory_put = letter_cutter.allow_metadata_inventory_put,
-	-- Taking is allowed from all slots (even the internal microblock slot). Moving is forbidden.
-	-- Putting something in is slightly more complicated than taking anything because we have to make sure it is of a suitable material:
-	on_metadata_inventory_put = letter_cutter.on_metadata_inventory_put_lower,
-	on_metadata_inventory_take = letter_cutter.on_metadata_inventory_take_lower,
+	on_metadata_inventory_put = letter_cutter.on_metadata_inventory_put,
+	on_metadata_inventory_take = letter_cutter.on_metadata_inventory_take,
 	on_receive_fields = letter_cutter.on_receive_fields,
 })
 
@@ -585,17 +461,17 @@ minetest.register_node("letters:letter_cutter_upper",  {
 	node_box = {
 		type = "fixed",
 		fixed = {
-			{-0.4375, -0.5, -0.4375, -0.3125, 0.125, -0.3125}, -- NodeBox1
-			{-0.4375, -0.5, 0.3125, -0.3125, 0.125, 0.4375}, -- NodeBox2
-			{0.3125, -0.5, 0.3125, 0.4375, 0.125, 0.4375}, -- NodeBox3
-			{0.3125, -0.5, -0.4375, 0.4375, 0.125, -0.3125}, -- NodeBox4
-			{-0.5, 0.0625, -0.5, 0.5, 0.25, 0.5}, -- NodeBox5
-			{0.1875, 0.25, -0.125, 0.125, 0.3125, -0.3125}, -- NodeBox6
-			{0.125, 0.25, 0.125, 0.0625, 0.3125, -0.125}, -- NodeBox7
-			{0.0625, 0.25, 0.3125, -0.0625, 0.3125, 0.0625}, -- NodeBox8
-			{-0.0625, 0.25, 0.125, -0.125, 0.3125, -0.125}, -- NodeBox9
-			{-0.125, 0.25, -0.125, -0.1875, 0.3125, -0.3125}, -- NodeBox10
-			{0.125, 0.25, -0.125, -0.125, 0.3125, -0.1875}, -- NodeBox11
+			{-0.4375, -0.5, -0.4375, -0.3125, 0.125, -0.3125},
+			{-0.4375, -0.5, 0.3125, -0.3125, 0.125, 0.4375},
+			{0.3125, -0.5, 0.3125, 0.4375, 0.125, 0.4375},
+			{0.3125, -0.5, -0.4375, 0.4375, 0.125, -0.3125},
+			{-0.5, 0.0625, -0.5, 0.5, 0.25, 0.5},
+			{0.1875, 0.25, -0.125, 0.125, 0.3125, -0.3125},
+			{0.125, 0.25, 0.125, 0.0625, 0.3125, -0.125},
+			{0.0625, 0.25, 0.3125, -0.0625, 0.3125, 0.0625},
+			{-0.0625, 0.25, 0.125, -0.125, 0.3125, -0.125},
+			{-0.125, 0.25, -0.125, -0.1875, 0.3125, -0.3125},
+			{0.125, 0.25, -0.125, -0.125, 0.3125, -0.1875},
 		},
 	},
 	tiles = {"letters_letter_cutter_upper_top.png",
@@ -606,9 +482,9 @@ minetest.register_node("letters:letter_cutter_upper",  {
 	paramtype2 = "facedir",
 	groups = {choppy = 2,oddly_breakable_by_hand = 2},
 	sounds = default.node_sound_wood_defaults(),
-	on_construct = letter_cutter.on_construct_upper,
+	on_construct = letter_cutter.on_construct,
 	can_dig = letter_cutter.can_dig,
-	-- Set the owner of this circular saw.
+	-- Set the cutter type and owner.
 	after_place_node = function(pos, placer)
 		local meta = minetest.get_meta(pos)
 		local owner = placer and placer:get_player_name() or ""
@@ -618,12 +494,9 @@ minetest.register_node("letters:letter_cutter_upper",  {
 					..meta:get_string("owner")..")")
 	end,
 	allow_metadata_inventory_move = letter_cutter.allow_metadata_inventory_move,
-	-- Only input- and recycle-slot are intended as input slots:
 	allow_metadata_inventory_put = letter_cutter.allow_metadata_inventory_put,
-	-- Taking is allowed from all slots (even the internal microblock slot). Moving is forbidden.
-	-- Putting something in is slightly more complicated than taking anything because we have to make sure it is of a suitable material:
-	on_metadata_inventory_put = letter_cutter.on_metadata_inventory_put_upper,
-	on_metadata_inventory_take = letter_cutter.on_metadata_inventory_take_upper,
+	on_metadata_inventory_put = letter_cutter.on_metadata_inventory_put,
+	on_metadata_inventory_take = letter_cutter.on_metadata_inventory_take,
 	on_receive_fields = letter_cutter.on_receive_fields,
 })
 
@@ -636,4 +509,60 @@ minetest.register_craft({
 	},
 })
 
+minetest.register_node("letters:letter_cutter_digit",  {
+	description = "Digit Cutter",
+	drawtype = "nodebox",
+	node_box = {
+		type = "fixed",
+		fixed = {
+			{-0.4375, -0.5, -0.4375, -0.3125, 0.125, -0.3125},
+			{-0.4375, -0.5, 0.3125, -0.3125, 0.125, 0.4375},
+			{0.3125, -0.5, 0.3125, 0.4375, 0.125, 0.4375},
+			{0.3125, -0.5, -0.4375, 0.4375, 0.125, -0.3125},
+			{-0.5, 0.0625, -0.5, 0.5, 0.25, 0.5},
+			{-0.0625, 0.25, 0.3125, 0, 0.3125, 0.1875},
+			{0.125, 0.25, 0.3125, 0.1875, 0.3125, 0.1875},
+			{-0.25, 0.25, 0.125, 0.25, 0.3125, 0.1875},
+			{-0.125, 0.25, -0.0625, -0.0625, 0.3125, 0.125},
+			{0.0625, 0.25, -0.0625, 0.125, 0.3125, 0.125},
+			{-0.25, 0.25, -0.0625, 0.25, 0.3125, -0.125},
+			{-0.1875, 0.25, -0.125, -0.125, 0.3125, -0.25},
+			{0, 0.25, -0.125, 0.0625, 0.3125, -0.25},
+		},
+	},
+	tiles = {"letters_letter_cutter_digit_top.png",
+		"default_tree.png",
+		"letters_letter_cutter_side.png"},
+	paramtype = "light",
+	sunlight_propagates = true,
+	paramtype2 = "facedir",
+	groups = {choppy = 2,oddly_breakable_by_hand = 2},
+	sounds = default.node_sound_wood_defaults(),
+	on_construct = letter_cutter.on_construct,
+	can_dig = letter_cutter.can_dig,
+	-- Set the cutter type and owner.
+	after_place_node = function(pos, placer)
+		local meta = minetest.get_meta(pos)
+		local owner = placer and placer:get_player_name() or ""
+		meta:set_string("owner",  owner)
+		meta:set_string("infotext",
+				"Letter Cutter (Digit) is empty (owned by "
+					..meta:get_string("owner")..")")
+	end,
+	allow_metadata_inventory_move = letter_cutter.allow_metadata_inventory_move,
+	allow_metadata_inventory_put = letter_cutter.allow_metadata_inventory_put,
+	on_metadata_inventory_put = letter_cutter.on_metadata_inventory_put,
+	on_metadata_inventory_take = letter_cutter.on_metadata_inventory_take,
+	on_receive_fields = letter_cutter.on_receive_fields,
+})
+
+minetest.register_craft({
+	output = "letters:letter_cutter_digit",
+	recipe = {
+		{"default:tree", "default:tree", "default:tree"},
+		{"default:wood", "default:copper_ingot", "default:wood"},
+		{"default:tree", "", "default:tree"},
+	},
+})
+
 dofile(minetest.get_modpath("letters").."/registrations.lua")