Properly handle missing screwdriver mod

It used to be so that you could gain two sticky movestones out of one normal one,
this didn't make much sense.

.gitignore

@@ -0,0 +1 @@
+*~

README.md

@@ -53,6 +53,7 @@ These awesome people made Mesecons possible!
 
 | Contributor     | Contribution                     |
 | --------------- | -------------------------------- |
+| Hawk777         | Code for VoxelManip caching      |
 | Jat15           | Various tweaks.                  |
 | Jeija           | **Main developer! Everything.**  |
 | Jordach         | Noteblock sounds.                |

documentation.json

@@ -1,6 +1,6 @@
 {
 	"Conductors" : {
-		"Mesecon" : "mesecons/doc/mesecon",
+		"Mesecon" : "mesecons_wires/doc/mesecon",
 		"Insulated Wire" : "mesecons_insulated/doc/insulated",
 		"T-Junction" : "mesecons_extrawires/doc/tjunction",
 		"Crossing" : "mesecons_extrawires/doc/crossing",
@@ -42,6 +42,8 @@
 	},
 	"Logic" : {
 		"Luacontroller" : "mesecons_luacontroller/doc/luacontroller",
+		"FPGA" : "mesecons_fpga/doc/fpga",
+		"FPGA Programmer" : "mesecons_fpga/doc/programmer",
 		"Torch" : "mesecons_torch/doc/torch",
 		"Delayer" : "mesecons_delayer/doc/delayer",
 		"Gates" : {

mesecons/actionqueue.lua

@@ -87,8 +87,12 @@ minetest.register_globalstep(function (dtime)
 end)
 
 function mesecon.queue:execute(action)
+	-- ignore if action queue function name doesn't exist,
+	-- (e.g. in case the action queue savegame was written by an old mesecons version)
+	if mesecon.queue.funcs[action.func] then
 		mesecon.queue.funcs[action.func](action.pos, unpack(action.params))
 	end
+end
 
 
 -- Store and read the ActionQueue to / from a file

mesecons/depends.txt

@@ -1 +1,2 @@
 default
+screwdriver?

mesecons/doc/mesecon/description.html

@@ -1 +0,0 @@
- Mesecons are the wires, use them to connect effectors with receptors.

mesecons/init.lua

@@ -3,7 +3,7 @@
 -- |  \/  | |___ ____  |___ |      |    | | \  | |____
 -- |      | |        | |    |      |    | |  \ |     |
 -- |      | |___ ____| |___ |____  |____| |   \| ____|
--- by Jeija, Uberi (Temperest), sfan5, VanessaE
+-- by Jeija, Uberi (Temperest), sfan5, VanessaE, Hawk777 and contributors
 --
 --
 --
@@ -11,7 +11,7 @@
 -- See the documentation on the forum for additional information, especially about crafting
 --
 --
--- For developer documentation see the Developers' section on mesecons.TK
+-- For basic development resources, see http://mesecons.net/developers.html
 --
 --
 --
@@ -70,19 +70,11 @@ dofile(minetest.get_modpath("mesecons").."/internal.lua");
 -- these are the only functions you need to remember
 
 mesecon.queue:add_function("receptor_on", function (pos, rules)
+	mesecon.vm_begin()
+
 	rules = rules or mesecon.rules.default
 
-	-- if area (any of the rule targets) is not loaded, keep trying and call this again later
+	-- Call turnon on all linking positions
-	for _, rule in ipairs(mesecon.flattenrules(rules)) do
-		local np = vector.add(pos, rule)
-		-- if area is not loaded, keep trying
-		if minetest.get_node_or_nil(np) == nil then
-			mesecon.queue:add_action(pos, "receptor_on", {rules}, nil, rules)
-			return
-		end
-	end
-
-	-- execute action
 	for _, rule in ipairs(mesecon.flattenrules(rules)) do
 		local np = vector.add(pos, rule)
 		local rulenames = mesecon.rules_link_rule_all(pos, rule)
@@ -90,6 +82,8 @@ mesecon.queue:add_function("receptor_on", function (pos, rules)
 			mesecon.turnon(np, rulename)
 		end
 	end
+
+	mesecon.vm_commit()
 end)
 
 function mesecon.receptor_on(pos, rules)
@@ -99,23 +93,21 @@ end
 mesecon.queue:add_function("receptor_off", function (pos, rules)
 	rules = rules or mesecon.rules.default
 
-	-- if area (any of the rule targets) is not loaded, keep trying and call this again later
+	-- Call turnoff on all linking positions
-	for _, rule in ipairs(mesecon.flattenrules(rules)) do
-		local np = vector.add(pos, rule)
-		if minetest.get_node_or_nil(np) == nil then
-			mesecon.queue:add_action(pos, "receptor_off", {rules}, nil, rules)
-			return
-		end
-	end
-
 	for _, rule in ipairs(mesecon.flattenrules(rules)) do
 		local np = vector.add(pos, rule)
 		local rulenames = mesecon.rules_link_rule_all(pos, rule)
 		for _, rulename in ipairs(rulenames) do
-			if not mesecon.connected_to_receptor(np, mesecon.invertRule(rule)) then
+			mesecon.vm_begin()
-				mesecon.turnoff(np, rulename)
-			else
 			mesecon.changesignal(np, minetest.get_node(np), rulename, mesecon.state.off, 2)
+
+			-- Turnoff returns true if turnoff process was successful, no onstate receptor
+			-- was found along the way. Commit changes that were made in voxelmanip. If turnoff
+			-- returns true, an onstate receptor was found, abort voxelmanip transaction.
+			if (mesecon.turnoff(np, rulename)) then
+				mesecon.vm_commit()
+			else
+				mesecon.vm_abort()
 			end
 		end
 	end
@@ -126,14 +118,11 @@ function mesecon.receptor_off(pos, rules)
 end
 
 
-minetest.log("action", "[OK] Mesecons")
+print("[OK] Mesecons")
 
 -- Deprecated stuff
 -- To be removed in future releases
 dofile(minetest.get_modpath("mesecons").."/legacy.lua");
 
---The actual wires
-dofile(minetest.get_modpath("mesecons").."/wires.lua");
-
 --Services like turnoff receptor on dignode and so on
 dofile(minetest.get_modpath("mesecons").."/services.lua");

mesecons/internal.lua

@@ -37,11 +37,6 @@
 -- HIGH-LEVEL Internals
 -- mesecon.is_power_on(pos)				--> Returns true if pos emits power in any way
 -- mesecon.is_power_off(pos)				--> Returns true if pos does not emit power in any way
--- mesecon.turnon(pos, link) 				--> link is the input rule that caused calling turnon, turns on every connected node, iterative
--- mesecon.turnoff(pos, link)				--> link is the input rule that caused calling turnoff, turns off every connected node, iterative
--- mesecon.connected_to_receptor(pos, link)		--> Returns true if pos is connected to a receptor directly or via conductors, iterative
--- mesecon.rules_link(output, input, dug_outputrules)	--> Returns true if outputposition + outputrules = inputposition and inputposition + inputrules = outputposition (if the two positions connect)
--- mesecon.rules_link_anydir(outp., inp., d_outpr.)	--> Same as rules mesecon.rules_link but also returns true if output and input are swapped
 -- mesecon.is_powered(pos)				--> Returns true if pos is powered by a receptor or a conductor
 
 -- RULES ROTATION helpers
@@ -371,52 +366,32 @@ function mesecon.is_power_off(pos, rulename)
 	return false
 end
 
+-- Turn off an equipotential section starting at `pos`, which outputs in the direction of `link`.
+-- Breadth-first search. Map is abstracted away in a voxelmanip.
+-- Follow all all conductor paths replacing conductors that were already
+-- looked at, activating / changing all effectors along the way.
 function mesecon.turnon(pos, link)
 	local frontiers = {{pos = pos, link = link}}
 
 	local depth = 1
-	while frontiers[depth] do
+	while frontiers[1] do
-		local f = frontiers[depth]
+		local f = table.remove(frontiers, 1)
 		local node = mesecon.get_node_force(f.pos)
 
-		-- area not loaded, postpone action
 		if not node then
-			mesecon.queue:add_action(f.pos, "turnon", {f.link}, nil, true)
+			-- Area does not exist; do nothing
 		elseif mesecon.is_conductor_off(node, f.link) then
 			local rules = mesecon.conductor_get_rules(node)
 
-			-- Success: If false, at least one neighboring node is unloaded,
+			-- Call turnon on neighbors
-			-- postpone turning on action
-			local success = true
-			local neighborlinks = {}
-
-			-- call turnon on neighbors
 			for _, r in ipairs(mesecon.rule2meta(f.link, rules)) do
 				local np = vector.add(f.pos, r)
-
+				for _, l in ipairs(mesecon.rules_link_rule_all(f.pos, r)) do
-				-- Neighboring node not loaded, postpone turning on current node
+					table.insert(frontiers, {pos = np, link = l})
-				-- since we can't even know if neighboring node has matching rules
-				if not mesecon.get_node_force(np) then
-					success = false
-					break
-				else
-					neighborlinks[minetest.hash_node_position(np)] = mesecon.rules_link_rule_all(f.pos, r)
 				end
 			end
 
-			if success then
+			mesecon.swap_node_force(f.pos, mesecon.get_conductor_on(node, f.link))
-				minetest.swap_node(f.pos, {name = mesecon.get_conductor_on(node, f.link),
-					param2 = node.param2})
-
-				for npos, links in pairs(neighborlinks) do
-					-- links = all links to node, l = each single link
-					for _, l in ipairs(links) do
-						table.insert(frontiers, {pos = minetest.get_position_from_hash(npos), link = l})
-					end
-				end
-			else
-				mesecon.queue:add_action(f.pos, "turnon", {f.link}, nil, true)
-			end
 		elseif mesecon.is_effector(node.name) then
 			mesecon.changesignal(f.pos, node, f.link, mesecon.state.on, depth)
 			if mesecon.is_effector_off(node.name) then
@@ -427,151 +402,77 @@ function mesecon.turnon(pos, link)
 	end
 end
 
-mesecon.queue:add_function("turnon", function(pos, rulename, recdepth)
+-- Turn on an equipotential section starting at `pos`, which outputs in the direction of `link`.
-	mesecon.turnon(pos, rulename, recdepth)
+-- Breadth-first search. Map is abstracted away in a voxelmanip.
-end)
+-- Follow all all conductor paths replacing conductors that were already
-
+-- looked at, deactivating / changing all effectors along the way.
+-- In case an onstate receptor is discovered, abort the process by returning false, which will
+-- cause `receptor_off` to discard all changes made in the voxelmanip.
+-- Contrary to turnon, turnoff has to cache all change and deactivate signals so that they will only
+-- be called in the very end when we can be sure that no conductor was found along the path.
+--
+-- Signal table entry structure:
+-- {
+--	pos = position of effector,
+--	node = node descriptor (name, param1 and param2),
+--	link = link the effector is connected to,
+--	depth = indicates order in which signals wire fired, higher is later
+-- }
 function mesecon.turnoff(pos, link)
 	local frontiers = {{pos = pos, link = link}}
+	local signals = {}
 
 	local depth = 1
-	while frontiers[depth] do
+	while frontiers[1] do
-		local f = frontiers[depth]
+		local f = table.remove(frontiers, 1)
 		local node = mesecon.get_node_force(f.pos)
 
-		-- area not loaded, postpone action
 		if not node then
-			mesecon.queue:add_action(f.pos, "turnoff", {f.link}, nil, true)
+			-- Area does not exist; do nothing
 		elseif mesecon.is_conductor_on(node, f.link) then
 			local rules = mesecon.conductor_get_rules(node)
-
-			-- Success: If false, at least one neighboring node is unloaded,
-			-- postpone turning on action
-			local success = true
-			local neighborlinks = {}
-
-			-- call turnoff on neighbors
 			for _, r in ipairs(mesecon.rule2meta(f.link, rules)) do
 				local np = vector.add(f.pos, r)
 
-				-- Neighboring node not loaded, postpone turning off current node
+				-- Check if an onstate receptor is connected. If that is the case,
-				-- since we can't even know if neighboring node has matching rules
+				-- abort this turnoff process by returning false. `receptor_off` will
-				if not mesecon.get_node_force(np) then
+				-- discard all the changes that we made in the voxelmanip:
-					success = false
+				for _, l in ipairs(mesecon.rules_link_rule_all_inverted(f.pos, r)) do
-					break
+					if mesecon.is_receptor_on(mesecon.get_node_force(np).name) then
-				else
+						return false
-					neighborlinks[minetest.hash_node_position(np)] = mesecon.rules_link_rule_all(f.pos, r)
 					end
 				end
 
-			if success then
+				-- Call turnoff on neighbors
-				minetest.swap_node(f.pos, {name = mesecon.get_conductor_off(node, f.link),
+				for _, l in ipairs(mesecon.rules_link_rule_all(f.pos, r)) do
-					param2 = node.param2})
+					table.insert(frontiers, {pos = np, link = l})
+				end
+			end
 
-				for npos, links in pairs(neighborlinks) do
+			mesecon.swap_node_force(f.pos, mesecon.get_conductor_off(node, f.link))
-					-- links = all links to node, l = each single link
-					for _, l in ipairs(links) do
-						table.insert(frontiers, {pos = minetest.get_position_from_hash(npos), link = l})
-					end
-				end
-			else
-				mesecon.queue:add_action(f.pos, "turnoff", {f.link}, nil, true)
-			end
 		elseif mesecon.is_effector(node.name) then
-			mesecon.changesignal(f.pos, node, f.link, mesecon.state.off, depth)
+			table.insert(signals, {
-			if mesecon.is_effector_on(node.name) and not mesecon.is_powered(f.pos) then
+				pos = f.pos,
-				mesecon.deactivate(f.pos, node, f.link, depth)
+				node = node,
-			end
+				link = f.link,
+				depth = depth
+			})
 		end
 		depth = depth + 1
 	end
+
+	for _, sig in ipairs(signals) do
+		mesecon.changesignal(sig.pos, sig.node, sig.link, mesecon.state.off, sig.depth)
+		if mesecon.is_effector_on(sig.node.name) and not mesecon.is_powered(sig.pos) then
+			mesecon.deactivate(sig.pos, sig.node, sig.link, sig.depth)
+		end
 	end
 
-mesecon.queue:add_function("turnoff", function(pos, rulename, recdepth)
-	mesecon.turnoff(pos, rulename, recdepth)
-end)
-
-
-function mesecon.connected_to_receptor(pos, link)
-	local node = mesecon.get_node_force(pos)
-	if not node then return false end
-
-	-- Check if conductors around are connected
-	local rules = mesecon.get_any_inputrules(node)
-	if not rules then return false end
-
-	for _, rule in ipairs(mesecon.rule2meta(link, rules)) do
-		local links = mesecon.rules_link_rule_all_inverted(pos, rule)
-		for _, l in ipairs(links) do
-			local np = vector.add(pos, l)
-			if mesecon.find_receptor_on(np, mesecon.invertRule(l)) then
 	return true
 end
-		end
-	end
-
-	return false
-end
-
-function mesecon.find_receptor_on(pos, link)
-	local frontiers = {{pos = pos, link = link}}
-	local checked = {}
-
-	-- List of positions that have been searched for onstate receptors
-	local depth = 1
-	while frontiers[depth] do
-		local f = frontiers[depth]
-		local node = mesecon.get_node_force(f.pos)
-
-		if not node then return false end
-		if mesecon.is_receptor_on(node.name) then return true end
-		if mesecon.is_conductor_on(node, f.link) then
-			local rules = mesecon.conductor_get_rules(node)
-
-			-- call turnoff on neighbors: normal rules
-			for _, r in ipairs(mesecon.rule2meta(f.link, rules)) do
-				local np = vector.add(f.pos, r)
-
-				local links = mesecon.rules_link_rule_all_inverted(f.pos, r)
-				for _, l in ipairs(links) do
-					local checkedstring = np.x..np.y..np.z..l.x..l.y..l.z
-					if not checked[checkedstring] then
-						table.insert(frontiers, {pos = np, link = l})
-						checked[checkedstring] = true
-					end
-				end
-			end
-
-		end
-		depth = depth + 1
-	end
-end
-
-function mesecon.rules_link(output, input, dug_outputrules) --output/input are positions (outputrules optional, used if node has been dug), second return value: the name of the affected input rule
-	local outputnode = mesecon.get_node_force(output)
-	local inputnode = mesecon.get_node_force(input)
-
-	local outputrules = dug_outputrules or mesecon.get_any_outputrules(outputnode)
-	local inputrules = mesecon.get_any_inputrules(inputnode)
-	if not outputrules or not inputrules then
-		return
-	end
-
-	for _, outputrule in ipairs(mesecon.flattenrules(outputrules)) do
-		-- Check if output sends to input
-		if vector.equals(vector.add(output, outputrule), input) then
-			for _, inputrule in ipairs(mesecon.flattenrules(inputrules)) do
-				-- Check if input accepts from output
-				if  vector.equals(vector.add(input, inputrule), output) then
-					return true, inputrule
-				end
-			end
-		end
-	end
-
-	return false
-end
 
+-- Get all linking inputrules of inputnode (effector or conductor) that is connected to
+-- outputnode (receptor or conductor) at position `output` and has an output in direction `rule`
 function mesecon.rules_link_rule_all(output, rule)
 	local input = vector.add(output, rule)
 	local inputnode = mesecon.get_node_force(input)
@@ -591,8 +492,9 @@ function mesecon.rules_link_rule_all(output, rule)
 	return rules
 end
 
+-- Get all linking outputnodes of outputnode (receptor or conductor) that is connected to
+-- inputnode (effector or conductor) at position `input` and has an input in direction `rule`
 function mesecon.rules_link_rule_all_inverted(input, rule)
-	--local irule = mesecon.invertRule(rule)
 	local output = vector.add(input, rule)
 	local outputnode = mesecon.get_node_force(output)
 	local outputrules = mesecon.get_any_outputrules(outputnode)
@@ -609,10 +511,6 @@ function mesecon.rules_link_rule_all_inverted(input, rule)
 	return rules
 end
 
-function mesecon.rules_link_anydir(pos1, pos2)
-	return mesecon.rules_link(pos1, pos2) or mesecon.rules_link(pos2, pos1)
-end
-
 function mesecon.is_powered(pos, rule)
 	local node = mesecon.get_node_force(pos)
 	local rules = mesecon.get_any_inputrules(node)

mesecons/legacy.lua

@@ -1,30 +1,97 @@
--- Ugly hack to prevent breaking compatibility with other mods
+-- Un-forceload any forceloaded mapblocks from older versions of Mesecons which
--- Just remove the following two functions to delete the hack, to be done when other mods have updated
+-- used forceloading instead of VoxelManipulators.
-function mesecon.receptor_on(self, pos, rules)
+local BLOCKSIZE = 16
-	if (self.receptor_on) then
+
-		print("[Mesecons] Warning: A mod with mesecon support called mesecon:receptor_on.")
+-- convert block hash --> node position
-		print("[Mesecons]          If you are the programmer of this mod, please update it ")
+local function unhash_blockpos(hash)
-		print("[Mesecons]          to use mesecon.receptor_on instead. mesecon:* is deprecated")
+	return vector.multiply(minetest.get_position_from_hash(hash), BLOCKSIZE)
-		print("[Mesecons]          Otherwise, please make sure you're running the latest version")
-		print("[Mesecons]          of that mod and inform the mod creator.")
-	else
-		rules = pos
-		pos = self
-	end
-	mesecon.queue:add_action(pos, "receptor_on", {rules}, nil, rules)
 end
 
-function mesecon.receptor_off(self, pos, rules)
+local old_forceloaded_blocks = mesecon.file2table("mesecon_forceloaded")
-	if (self.receptor_off) then
+for hash, _ in pairs(old_forceloaded_blocks) do
-		print("[Mesecons] Warning: A mod with mesecon support called mesecon:receptor_off.")
+	minetest.forceload_free_block(unhash_blockpos(hash))
-		print("[Mesecons]          If you are the programmer of this mod, please update it ")
-		print("[Mesecons]          to use mesecon.receptor_off instead. mesecon:* is deprecated")
-		print("[Mesecons]          Otherwise, please make sure you're running the latest version")
-		print("[Mesecons]          of that mod and inform the mod creator.")
-	else
-		rules = pos
-		pos = self
-	end
-	mesecon.queue:add_action(pos, "receptor_off", {rules}, nil, rules)
 end
+os.remove(minetest.get_worldpath()..DIR_DELIM.."mesecon_forceloaded")
 
+-- LBMs to convert old pistons to use facedir instead of separate up/down nodes
+minetest.register_lbm({
+	label = "Convert up pistons to use facedir",
+	name = ":mesecons_pistons:update_up_pistons",
+	nodenames = {"mesecons_pistons:piston_up_normal_on","mesecons_pistons:piston_up_normal_off",
+			"mesecons_pistons:piston_up_sticky_on","mesecons_pistons:piston_up_sticky_off"},
+	action = function(pos, node)
+		if string.find(node.name, "sticky") then
+			if string.sub(node.name, -3, -1) == "_on" then
+				node.name = "mesecons_pistons:piston_sticky_on"
+			else
+				node.name = "mesecons_pistons:piston_sticky_off"
+			end
+		else
+			if string.sub(node.name, -3, -1) == "_on" then
+				node.name = "mesecons_pistons:piston_normal_on"
+			else
+				node.name = "mesecons_pistons:piston_normal_off"
+			end
+		end
+		local dir = {x=0, y=-1, z=0}
+		node.param2 = minetest.dir_to_facedir(dir, true)
+		minetest.swap_node(pos, node)
+	end
+})
+
+minetest.register_lbm({
+	label = "Convert down pistons to use facedir",
+	name = ":mesecons_pistons:update_down_pistons",
+	nodenames = {"mesecons_pistons:piston_down_normal_on","mesecons_pistons:piston_down_normal_off",
+			"mesecons_pistons:piston_down_sticky_on","mesecons_pistons:piston_down_sticky_off"},
+	action = function(pos, node)
+		if string.find(node.name, "sticky") then
+			if string.sub(node.name, -3, -1) == "_on" then
+				node.name = "mesecons_pistons:piston_sticky_on"
+			else
+				node.name = "mesecons_pistons:piston_sticky_off"
+			end
+		else
+			if string.sub(node.name, -3, -1) == "_on" then
+				node.name = "mesecons_pistons:piston_normal_on"
+			else
+				node.name = "mesecons_pistons:piston_normal_off"
+			end
+		end
+		local dir = {x=0, y=1, z=0}
+		node.param2 = minetest.dir_to_facedir(dir, true)
+		minetest.swap_node(pos, node)
+	end
+})
+
+minetest.register_lbm({
+	label = "Convert up piston pushers to use facedir",
+	name = ":mesecons_pistons:update_up_pushers",
+	nodenames = {"mesecons_pistons:piston_up_pusher_normal", "mesecons_pistons:piston_up_pusher_sticky"},
+	action = function(pos, node)
+		if string.find(node.name, "sticky") then
+			node.name = "mesecons_pistons:piston_pusher_sticky"
+		else
+			node.name = "mesecons_pistons:piston_pusher_normal"
+		end
+		local dir = {x=0, y=-1, z=0}
+		node.param2 = minetest.dir_to_facedir(dir, true)
+		minetest.swap_node(pos, node)
+	end
+})
+
+minetest.register_lbm({
+	label = "Convert down piston pushers to use facedir",
+	name = ":mesecons_pistons:update_down_pushers",
+	nodenames = {"mesecons_pistons:piston_down_pusher_normal", "mesecons_pistons:piston_down_pusher_sticky"},
+	action = function(pos, node)
+		if string.find(node.name, "sticky") then
+			node.name = "mesecons_pistons:piston_pusher_sticky"
+		else
+			node.name = "mesecons_pistons:piston_pusher_normal"
+		end
+		local dir = {x=0, y=1, z=0}
+		node.param2 = minetest.dir_to_facedir(dir, true)
+		minetest.swap_node(pos, node)
+	end
+})

mesecons/oldwires.lua

@@ -10,7 +10,7 @@ minetest.register_node("mesecons:mesecon_off", {
 		type = "fixed",
 		fixed = {-0.5, -0.5, -0.5, 0.5, -0.45, 0.5},
 	},
-	groups = {dig_immediate=2, mesecon=1, mesecon_conductor_craftable=1}, --MFF
+	groups = {dig_immediate=3, mesecon=1, mesecon_conductor_craftable=1},
     	description="Mesecons",
 	mesecons = {conductor={
 		state = mesecon.state.off,
@@ -28,7 +28,7 @@ minetest.register_node("mesecons:mesecon_on", {
 		type = "fixed",
 		fixed = {-0.5, -0.5, -0.5, 0.5, -0.45, 0.5},
 	},
-	groups = {dig_immediate=2, not_in_creaive_inventory=1, mesecon=1}, --MFF
+	groups = {dig_immediate=3, not_in_creaive_inventory=1, mesecon=1},
 	drop = "mesecons:mesecon_off 1",
 	light_source = default.LIGHT_MAX-11,
 	mesecons = {conductor={

mesecons/presets.lua

@@ -41,12 +41,19 @@ mesecon.rules.alldirs =
 
 mesecon.rules.buttonlike_get = function(node)
 	local rules = mesecon.rules.buttonlike
-	if node.param2 == 2 then
+	local dir = minetest.facedir_to_dir(node.param2)
+	if dir.x == 1 then
+		-- No action needed
+	elseif dir.z == -1 then
 		rules=mesecon.rotate_rules_left(rules)
-	elseif node.param2 == 3 then
+	elseif dir.x == -1 then
 		rules=mesecon.rotate_rules_right(mesecon.rotate_rules_right(rules))
-	elseif node.param2 == 0 then
+	elseif dir.z == 1 then
 		rules=mesecon.rotate_rules_right(rules)
+	elseif dir.y == -1 then
+		rules=mesecon.rotate_rules_up(rules)
+	elseif dir.y == 1 then
+		rules=mesecon.rotate_rules_down(rules)
 	end
 	return rules
 end

mesecons/services.lua

@@ -1,7 +1,7 @@
 -- Dig and place services
 
 mesecon.on_placenode = function(pos, node)
-	mesecon.update_autoconnect(pos, node)
+	mesecon.execute_autoconnect_hooks_now(pos, node)
 
 	-- Receptors: Send on signal when active
 	if mesecon.is_receptor_on(node.name) then
@@ -58,10 +58,9 @@ mesecon.on_dignode = function (pos, node)
 	elseif mesecon.is_receptor_on(node.name) then
 		mesecon.receptor_off(pos, mesecon.receptor_get_rules(node))
 	end
-	mesecon.queue:add_action(pos, "update_autoconnect", {node})
-end
 
-mesecon.queue:add_function("update_autoconnect", mesecon.update_autoconnect)
+	mesecon.execute_autoconnect_hooks_queue(pos, node)
+end
 
 minetest.register_on_placenode(mesecon.on_placenode)
 minetest.register_on_dignode(mesecon.on_dignode)
@@ -94,3 +93,11 @@ mesecon.queue:add_function("cooldown", function (pos)
 		meta:set_int("heat", heat - 1)
 	end
 end)
+
+-- "Shim" for simple rotation, will result in the following item in nodedefs using it:
+-- "on_rotate = screwdriver.rotate_simple" if screwdriver mod is installed
+-- "on_rotate = nil" (essentially not present) if screwdriver mod is missing
+
+if screwdriver then
+	mesecon.rotate_simple = screwdriver.rotate_simple
+end

mesecons/util.lua

@@ -219,7 +219,7 @@ function mesecon.table2file(filename, table)
 	f:close()
 end
 
--- Forceloading: Force server to load area if node is nil
+-- Block position "hashing" (convert to integer) functions for voxelmanip cache
 local BLOCKSIZE = 16
 
 -- convert node position --> block hash
@@ -231,45 +231,160 @@ local function hash_blockpos(pos)
 	})
 end
 
--- convert block hash --> node position
+-- Maps from a hashed mapblock position (as returned by hash_blockpos) to a
-local function unhash_blockpos(hash)
+-- table.
-	return vector.multiply(minetest.get_position_from_hash(hash), BLOCKSIZE)
+--
+-- Contents of the table are:
+-- “vm” → the VoxelManipulator
+-- “va” → the VoxelArea
+-- “data” → the data array
+-- “param1” → the param1 array
+-- “param2” → the param2 array
+-- “dirty” → true if data has been modified
+--
+-- Nil if no VM-based transaction is in progress.
+local vm_cache = nil
+
+-- Starts a VoxelManipulator-based transaction.
+--
+-- During a VM transaction, calls to vm_get_node and vm_swap_node operate on a
+-- cached copy of the world loaded via VoxelManipulators. That cache can later
+-- be committed to the real map by means of vm_commit or discarded by means of
+-- vm_abort.
+function mesecon.vm_begin()
+	vm_cache = {}
 end
 
-mesecon.forceloaded_blocks = {}
+-- Finishes a VoxelManipulator-based transaction, freeing the VMs and map data
+-- and writing back any modified areas.
+function mesecon.vm_commit()
+	for hash, tbl in pairs(vm_cache) do
+		if tbl.dirty then
+			local vm = tbl.vm
+			vm:set_data(tbl.data)
+			vm:write_to_map()
+			vm:update_map()
+		end
+	end
+	vm_cache = nil
+end
 
--- get node and force-load area
+-- Finishes a VoxelManipulator-based transaction, freeing the VMs and throwing
-function mesecon.get_node_force(pos)
+-- away any modified areas.
+function mesecon.vm_abort()
+	vm_cache = nil
+end
+
+-- Gets the cache entry covering a position, populating it if necessary.
+local function vm_get_or_create_entry(pos)
 	local hash = hash_blockpos(pos)
-
+	local tbl = vm_cache[hash]
-	if mesecon.forceloaded_blocks[hash] == nil then
+	if not tbl then
-		-- if no more forceload spaces are available, try again next time
+		local vm = minetest.get_voxel_manip(pos, pos)
-		if minetest.forceload_block(pos) then
+		local min_pos, max_pos = vm:get_emerged_area()
-			mesecon.forceloaded_blocks[hash] = 0
+		local va = VoxelArea:new{MinEdge = min_pos, MaxEdge = max_pos}
+		tbl = {vm = vm, va = va, data = vm:get_data(), param1 = vm:get_light_data(), param2 = vm:get_param2_data(), dirty = false}
+		vm_cache[hash] = tbl
 	end
+	return tbl
+end
+
+-- Gets the node at a given position during a VoxelManipulator-based
+-- transaction.
+function mesecon.vm_get_node(pos)
+	local tbl = vm_get_or_create_entry(pos)
+	local index = tbl.va:indexp(pos)
+	local node_value = tbl.data[index]
+	if node_value == core.CONTENT_IGNORE then
+		return nil
 	else
-		mesecon.forceloaded_blocks[hash] = 0
+		local node_param1 = tbl.param1[index]
+		local node_param2 = tbl.param2[index]
+		return {name = minetest.get_name_from_content_id(node_value), param1 = node_param1, param2 = node_param2}
+	end
 end
 
-	return minetest.get_node_or_nil(pos)
+-- Sets a node’s name during a VoxelManipulator-based transaction.
+--
+-- Existing param1, param2, and metadata are left alone.
+function mesecon.vm_swap_node(pos, name)
+	local tbl = vm_get_or_create_entry(pos)
+	local index = tbl.va:indexp(pos)
+	tbl.data[index] = minetest.get_content_id(name)
+	tbl.dirty = true
 end
 
-minetest.register_globalstep(function (dtime)
+-- Gets the node at a given position, regardless of whether it is loaded or
-	for hash, time in pairs(mesecon.forceloaded_blocks) do
+-- not, respecting a transaction if one is in progress.
-		-- unload forceloaded blocks after 10 minutes without usage
+--
-		if (time > mesecon.setting("forceload_timeout", 600)) then
+-- Outside a VM transaction, if the mapblock is not loaded, it is pulled into
-			minetest.forceload_free_block(unhash_blockpos(hash))
+-- the server’s main map data cache and then accessed from there.
-			mesecon.forceloaded_blocks[hash] = nil
+--
+-- Inside a VM transaction, the transaction’s VM cache is used.
+function mesecon.get_node_force(pos)
+	if vm_cache then
+		return mesecon.vm_get_node(pos)
 	else
-			mesecon.forceloaded_blocks[hash] = time + dtime
+		local node = minetest.get_node_or_nil(pos)
+		if node == nil then
+			-- Node is not currently loaded; use a VoxelManipulator to prime
+			-- the mapblock cache and try again.
+			minetest.get_voxel_manip(pos, pos)
+			node = minetest.get_node_or_nil(pos)
+		end
+		return node
 	end
 end
-end)
 
--- Store and read the forceloaded blocks to / from a file
+-- Swaps the node at a given position, regardless of whether it is loaded or
--- so that those blocks are remembered when the game
+-- not, respecting a transaction if one is in progress.
--- is restarted
+--
-mesecon.forceloaded_blocks = mesecon.file2table("mesecon_forceloaded")
+-- Outside a VM transaction, if the mapblock is not loaded, it is pulled into
-minetest.register_on_shutdown(function()
+-- the server’s main map data cache and then accessed from there.
-	mesecon.table2file("mesecon_forceloaded", mesecon.forceloaded_blocks)
+--
-end)
+-- Inside a VM transaction, the transaction’s VM cache is used.
+--
+-- This function can only be used to change the node’s name, not its parameters
+-- or metadata.
+function mesecon.swap_node_force(pos, name)
+	if vm_cache then
+		return mesecon.vm_swap_node(pos, name)
+	else
+		-- This serves to both ensure the mapblock is loaded and also hand us
+		-- the old node table so we can preserve param2.
+		local node = mesecon.get_node_force(pos)
+		node.name = name
+		minetest.swap_node(pos, node)
+	end
+end
+
+-- Autoconnect Hooks
+-- Nodes like conductors may change their appearance and their connection rules
+-- right after being placed or after being dug, e.g. the default wires use this
+-- to automatically connect to linking nodes after placement.
+-- After placement, the update function will be executed immediately so that the
+-- possibly changed rules can be taken into account when recalculating the circuit.
+-- After digging, the update function will be queued and executed after
+-- recalculating the circuit. The update function must take care of updating the
+-- node at the given position itself, but also all of the other nodes the given
+-- position may have (had) a linking connection to.
+mesecon.autoconnect_hooks = {}
+
+-- name: A unique name for the hook, e.g. "foowire". Used to name the actionqueue function.
+-- fct: The update function with parameters function(pos, node)
+function mesecon.register_autoconnect_hook(name, fct)
+	mesecon.autoconnect_hooks[name] = fct
+	mesecon.queue:add_function("autoconnect_hook_"..name, fct)
+end
+
+function mesecon.execute_autoconnect_hooks_now(pos, node)
+	for _, fct in pairs(mesecon.autoconnect_hooks) do
+		fct(pos, node)
+	end
+end
+
+function mesecon.execute_autoconnect_hooks_queue(pos, node)
+	for name in pairs(mesecon.autoconnect_hooks) do
+		mesecon.queue:add_action(pos, "autoconnect_hook_"..name, {node})
+	end
+end

mesecons_blinkyplant/init.lua

@@ -10,26 +10,12 @@ local toggle_timer = function (pos)
 end
 
 local on_timer = function (pos)
-	-- DO NOT TOUCH OR.. THREATS! Thanks, MFF
-	local activate = false
-	for _, player in pairs(minetest.get_connected_players()) do
-		local p = player:getpos()
-		local dist = ((p.x-pos.x)^2 + (p.y-pos.y)^2 + (p.z-pos.z)^2)^0.5
-		if dist < 40 then
-			activate = true
-			break
-		end
-	end
-
-	if activate then
 	local node = minetest.get_node(pos)
 	if(mesecon.flipstate(pos, node) == "on") then
 		mesecon.receptor_on(pos)
 	else
 		mesecon.receptor_off(pos)
 	end
-	-- Our modification stops there, thank you, @crabman77
-	end
 	toggle_timer(pos)
 end
 

mesecons_button/init.lua

@@ -26,6 +26,7 @@ minetest.register_node("mesecons_button:button_off", {
 	paramtype2 = "facedir",
 	legacy_wallmounted = true,
 	walkable = false,
+	on_rotate = mesecon.buttonlike_onrotate,
 	sunlight_propagates = true,
 	selection_box = {
 	type = "fixed",
@@ -67,6 +68,7 @@ minetest.register_node("mesecons_button:button_on", {
 	paramtype2 = "facedir",
 	legacy_wallmounted = true,
 	walkable = false,
+	on_rotate = false,
 	light_source = default.LIGHT_MAX-7,
 	sunlight_propagates = true,
 	selection_box = {

mesecons_delayer/init.lua

@@ -47,7 +47,8 @@ elseif	i == 2 then delaytime = 0.3
 elseif	i == 3 then delaytime = 0.5
 elseif	i == 4 then delaytime = 1.0 end
 
-boxes = {{ -6/16, -8/16, -6/16, 6/16, -7/16, 6/16 },		-- the main slab
+local boxes = {
+	 { -6/16, -8/16, -6/16, 6/16, -7/16, 6/16 },		-- the main slab
 
 	 { -2/16, -7/16, -4/16, 2/16, -26/64, -3/16 },		-- the jeweled "on" indicator
 	 { -3/16, -7/16, -3/16, 3/16, -26/64, -2/16 },
@@ -57,7 +58,8 @@ boxes = {{ -6/16, -8/16, -6/16, 6/16, -7/16, 6/16 },		-- the main slab
 
 	 { -6/16, -7/16, -6/16, -4/16, -27/64, -4/16 },		-- the timer indicator
 	 { -8/16, -8/16, -1/16, -6/16, -7/16, 1/16 },		-- the two wire stubs
-	 { 6/16, -8/16, -1/16, 8/16, -7/16, 1/16 }}
+	 { 6/16, -8/16, -1/16, 8/16, -7/16, 1/16 }
+}
 
 minetest.register_node("mesecons_delayer:delayer_off_"..tostring(i), {
 	description = "Delayer",

mesecons_detector/init.lua

@@ -4,11 +4,9 @@ local GET_COMMAND = "GET"
 -- Detects players in a certain radius
 -- The radius can be specified in mesecons/settings.lua
 
--- The following file was modified to detect multiple players
+local function object_detector_make_formspec(pos)
-local object_detector_make_formspec = function (pos)
+	minetest.get_meta(pos):set_string("formspec", "size[9,2.5]" ..
-	local meta = minetest.get_meta(pos)
+		"field[0.3,  0;9,2;scanname;Name of player to scan for (empty for any):;${scanname}]"..
-	meta:set_string("formspec", "size[9,2.5]" ..
-		"field[0.3,  0;12,2;scanname;Name of player(s) to scan for (empty for any, separate with comma):;${scanname}]"..
 		"field[0.3,1.5;4,2;digiline_channel;Digiline Channel (optional):;${digiline_channel}]"..
 		"button_exit[7,0.75;2,3;;Save]")
 end
@@ -25,25 +23,24 @@ end
 -- returns true if player was found, false if not
 local function object_detector_scan(pos)
 	local objs = minetest.get_objects_inside_radius(pos, mesecon.setting("detector_radius", 6))
-	for k, obj in pairs(objs) do
+
-		local isname = obj:get_player_name() -- "" is returned if it is not a player; "" ~= nil!
+	-- abort if no scan results were found
-		local scanname = minetest.get_meta(pos):get_string("scanname"):gsub(' ', "")
+	if next(objs) == nil then return false end
-		if (scanname == "" and isname ~= "") then
+
-			minetest.get_meta(pos):set_string("scanedname", "")
+	local scanname = minetest.get_meta(pos):get_string("scanname")
-			return true
+	local every_player = scanname == ""
-		end
+	for _, obj in pairs(objs) do
-		local founds = {}
+		-- "" is returned if it is not a player; "" ~= nil; so only handle objects with foundname ~= ""
-		for _, name in pairs(scanname:split(',')) do
+		local foundname = obj:get_player_name()
-			if (isname == name and isname ~= "") then
+
-				table.insert(founds, isname)
+		if foundname ~= "" then
-			end
+			-- return true if scanning for any player or if specific playername was detected
-		end
+			if scanname == "" or foundname == scanname then
-		if #founds > 0 then
-			minetest.get_meta(pos):set_string("scannedname", table.concat(founds, ','))
 				return true
 			end
 		end
-	minetest.get_meta(pos):set_string("scanedname", "")
+	end
+
 	return false
 end
 
@@ -52,9 +49,8 @@ local object_detector_digiline = {
 	effector = {
 		action = function(pos, node, channel, msg)
 			local meta = minetest.get_meta(pos)
-			local active_channel = meta:get_string("digiline_channel")
+			if channel == meta:get_string("digiline_channel") then
-			if channel == active_channel then
+				meta:set_string("scanname", msg)
-				meta:set_string("scanedname", msg)
 				object_detector_make_formspec(pos)
 			end
 		end,

mesecons_doors/init.lua

@@ -74,19 +74,6 @@ meseconify_door("doors:door_steel")
 meseconify_door("doors:door_glass")
 meseconify_door("doors:door_obsidian_glass")
 
---MFF meseconify all doors, crabman 12/06/2016 
-meseconify_door("doors:door_cherry")
-meseconify_door("doors:door_tin")
-meseconify_door("doors:door_prison")
-meseconify_door("doors:door_gardengate_white")
-meseconify_door("doors:door3_wood")
-meseconify_door("doors:door3_steel")
-meseconify_door("doors:door3_glass")
-meseconify_door("doors:door3_obsidian_glass")
-meseconify_door("doors:door3_cherry")
-meseconify_door("doors:door3_prison")
-
-
 -- Trapdoor
 local function trapdoor_switch(pos, node)
 	local state = minetest.get_meta(pos):get_int("state")

mesecons_extrawires/corner.lua

@@ -37,7 +37,8 @@ minetest.register_node("mesecons_extrawires:corner_on", {
 	sunlight_propagates = true,
 	selection_box = corner_selectionbox,
 	node_box = corner_nodebox,
-	groups = {dig_immediate = 2, not_in_creative_inventory = 1}, -- MFF
+	on_rotate = mesecon.rotate_simple,
+	groups = {dig_immediate = 3, not_in_creative_inventory = 1},
 	drop = "mesecons_extrawires:corner_off",
 	mesecons = {conductor =
 	{
@@ -49,7 +50,7 @@ minetest.register_node("mesecons_extrawires:corner_on", {
 
 minetest.register_node("mesecons_extrawires:corner_off", {
 	drawtype = "nodebox",
-	description = "Mesecon Corner",
+	description = "Insulated Mesecon Corner",
 	tiles = {
 		"jeija_insulated_wire_curved_tb_off.png",
 		"jeija_insulated_wire_curved_tb_off.png^[transformR270",
@@ -64,7 +65,8 @@ minetest.register_node("mesecons_extrawires:corner_off", {
 	sunlight_propagates = true,
 	selection_box = corner_selectionbox,
 	node_box = corner_nodebox,
-	groups = {dig_immediate = 2}, --MFF
+	on_rotate = mesecon.rotate_simple,
+	groups = {dig_immediate = 3},
 	mesecons = {conductor =
 	{
 		state = mesecon.state.off,

mesecons_extrawires/crossover.lua

@@ -1,4 +1,4 @@
-function crossover_get_rules(node)
+local function crossover_get_rules(node)
 	return {
 		{--first wire
 			{x=-1,y=0,z=0},
@@ -19,29 +19,20 @@ local crossover_states = {
 }
 
 minetest.register_node("mesecons_extrawires:crossover_off", {
-	description = "Insulated Crossover",
+	description = "Insulated Mesecon Crossover",
-	drawtype = "nodebox",
+	drawtype = "mesh",
+	mesh = "mesecons_extrawires_crossover.b3d",
 	tiles = {
-		"jeija_insulated_wire_crossing_tb_off.png",
+		"jeija_insulated_wire_ends_off.png",
-		"jeija_insulated_wire_crossing_tb_off.png",
+		"jeija_insulated_wire_sides_off.png",
+		"jeija_insulated_wire_sides_off.png",
 		"jeija_insulated_wire_ends_off.png"
 	},
 	paramtype = "light",
 	walkable = false,
 	stack_max = 99,
 	selection_box = {type="fixed", fixed={-16/32-0.0001, -18/32, -16/32-0.001, 16/32+0.001, -5/32, 16/32+0.001}},
-	node_box = {
+	groups = {dig_immediate=3, mesecon=3},
-		type = "fixed",
-		fixed = {
-			{ -16/32-0.001, -17/32, -3/32, 16/32+0.001, -13/32, 3/32 },
-			{ -3/32, -17/32, -16/32-0.001, 3/32, -13/32, -6/32 },
-			{ -3/32, -13/32, -9/32, 3/32, -6/32, -6/32 },
-			{ -3/32, -9/32, -9/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -13/32, 6/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -17/32, 6/32, 3/32, -13/32, 16/32+0.001 },
-		},
-	},
-	groups = {dig_immediate=2, mesecon=3}, --MFF
 	mesecons = {
 		conductor = {
 			states = crossover_states,
@@ -53,31 +44,19 @@ minetest.register_node("mesecons_extrawires:crossover_off", {
 minetest.register_node("mesecons_extrawires:crossover_01", {
 	description = "You hacker you!",
 	drop = "mesecons_extrawires:crossover_off",
-	drawtype = "nodebox",
+	drawtype = "mesh",
+	mesh = "mesecons_extrawires_crossover.b3d",
 	tiles = {
-		"jeija_insulated_wire_crossing_tb_01.png",
+		"jeija_insulated_wire_ends_on.png",
-		"jeija_insulated_wire_crossing_tb_01.png",
+		"jeija_insulated_wire_sides_on.png",
-		"jeija_insulated_wire_ends_01x.png",
+		"jeija_insulated_wire_sides_off.png",
-		"jeija_insulated_wire_ends_01x.png",
+		"jeija_insulated_wire_ends_off.png"
-		"jeija_insulated_wire_ends_01z.png",
-		"jeija_insulated_wire_ends_01z.png"
 	},
 	paramtype = "light",
 	walkable = false,
 	stack_max = 99,
 	selection_box = {type="fixed", fixed={-16/32-0.0001, -18/32, -16/32-0.001, 16/32+0.001, -5/32, 16/32+0.001}},
-	node_box = {
+	groups = {dig_immediate=3, mesecon=3, not_in_creative_inventory=1},
-		type = "fixed",
-		fixed = {
-			{ -16/32-0.001, -17/32, -3/32, 16/32+0.001, -13/32, 3/32 },
-			{ -3/32, -17/32, -16/32-0.001, 3/32, -13/32, -6/32 },
-			{ -3/32, -13/32, -9/32, 3/32, -6/32, -6/32 },
-			{ -3/32, -9/32, -9/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -13/32, 6/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -17/32, 6/32, 3/32, -13/32, 16/32+0.001 },
-		},
-	},
-	groups = {dig_immediate=2, mesecon=3, not_in_creative_inventory=1}, --MFF
 	mesecons = {
 		conductor = {
 			states = crossover_states,
@@ -89,30 +68,18 @@ minetest.register_node("mesecons_extrawires:crossover_01", {
 minetest.register_node("mesecons_extrawires:crossover_10", {
 	description = "You hacker you!",
 	drop = "mesecons_extrawires:crossover_off",
-	drawtype = "nodebox",
+	drawtype = "mesh",
+	mesh = "mesecons_extrawires_crossover.b3d",
 	tiles = {
-		"jeija_insulated_wire_crossing_tb_10.png",
+		"jeija_insulated_wire_ends_off.png",
-		"jeija_insulated_wire_crossing_tb_10.png",
+		"jeija_insulated_wire_sides_off.png",
-		"jeija_insulated_wire_ends_10x.png",
+		"jeija_insulated_wire_sides_on.png",
-		"jeija_insulated_wire_ends_10x.png",
+		"jeija_insulated_wire_ends_on.png"
-		"jeija_insulated_wire_ends_10z.png",
-		"jeija_insulated_wire_ends_10z.png"
 	},
 	paramtype = "light",
 	walkable = false,
 	stack_max = 99,
 	selection_box = {type="fixed", fixed={-16/32-0.0001, -18/32, -16/32-0.001, 16/32+0.001, -5/32, 16/32+0.001}},
-	node_box = {
-		type = "fixed",
-		fixed = {
-			{ -16/32-0.001, -17/32, -3/32, 16/32+0.001, -13/32, 3/32 },
-			{ -3/32, -17/32, -16/32-0.001, 3/32, -13/32, -6/32 },
-			{ -3/32, -13/32, -9/32, 3/32, -6/32, -6/32 },
-			{ -3/32, -9/32, -9/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -13/32, 6/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -17/32, 6/32, 3/32, -13/32, 16/32+0.001 },
-		},
-	},
 	groups = {dig_immediate=3, mesecon=3, not_in_creative_inventory=1},
 	mesecons = {
 		conductor = {
@@ -125,30 +92,18 @@ minetest.register_node("mesecons_extrawires:crossover_10", {
 minetest.register_node("mesecons_extrawires:crossover_on", {
 	description = "You hacker you!",
 	drop = "mesecons_extrawires:crossover_off",
-	drawtype = "nodebox",
+	drawtype = "mesh",
+	mesh = "mesecons_extrawires_crossover.b3d",
 	tiles = {
-		"jeija_insulated_wire_crossing_tb_on.png",
-		"jeija_insulated_wire_crossing_tb_on.png",
-		"jeija_insulated_wire_ends_on.png",
-		"jeija_insulated_wire_ends_on.png",
 		"jeija_insulated_wire_ends_on.png",
+		"jeija_insulated_wire_sides_on.png",
+		"jeija_insulated_wire_sides_on.png",
 		"jeija_insulated_wire_ends_on.png"
 	},
 	paramtype = "light",
 	walkable = false,
 	stack_max = 99,
 	selection_box = {type="fixed", fixed={-16/32-0.0001, -18/32, -16/32-0.001, 16/32+0.001, -5/32, 16/32+0.001}},
-	node_box = {
-		type = "fixed",
-		fixed = {
-			{ -16/32-0.001, -17/32, -3/32, 16/32+0.001, -13/32, 3/32 },
-			{ -3/32, -17/32, -16/32-0.001, 3/32, -13/32, -6/32 },
-			{ -3/32, -13/32, -9/32, 3/32, -6/32, -6/32 },
-			{ -3/32, -9/32, -9/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -13/32, 6/32, 3/32, -6/32, 9/32 },
-			{ -3/32, -17/32, 6/32, 3/32, -13/32, 16/32+0.001 },
-		},
-	},
 	groups = {dig_immediate=3, mesecon=3, not_in_creative_inventory=1},
 	mesecons = {
 		conductor = {

mesecons_extrawires/tjunction.lua

@@ -38,7 +38,8 @@ minetest.register_node("mesecons_extrawires:tjunction_on", {
 	sunlight_propagates = true,
 	selection_box = tjunction_selectionbox,
 	node_box = tjunction_nodebox,
-	groups = {dig_immediate = 2, not_in_creative_inventory = 1}, --MFF
+	on_rotate = mesecon.rotate_simple,
+	groups = {dig_immediate = 3, not_in_creative_inventory = 1},
 	drop = "mesecons_extrawires:tjunction_off",
 	mesecons = {conductor =
 	{
@@ -50,7 +51,7 @@ minetest.register_node("mesecons_extrawires:tjunction_on", {
 
 minetest.register_node("mesecons_extrawires:tjunction_off", {
 	drawtype = "nodebox",
-	description = "T-junction",
+	description = "Insulated Mesecon T-junction",
 	tiles = {
 		"jeija_insulated_wire_tjunction_tb_off.png",
 		"jeija_insulated_wire_tjunction_tb_off.png^[transformR180",
@@ -65,7 +66,8 @@ minetest.register_node("mesecons_extrawires:tjunction_off", {
 	sunlight_propagates = true,
 	selection_box = tjunction_selectionbox,
 	node_box = tjunction_nodebox,
-	groups = {dig_immediate = 2}, --MFF
+	on_rotate = mesecon.rotate_simple,
+	groups = {dig_immediate = 3},
 	mesecons = {conductor =
 	{
 		state = mesecon.state.off,

mesecons_extrawires/vertical.lua

@@ -84,13 +84,14 @@ mesecon.register_node("mesecons_extrawires:vertical", {
 	sunlight_propagates = true,
 	selection_box = vertical_box,
 	node_box = vertical_box,
+	on_rotate = false,
 	is_vertical_conductor = true,
 	drop = "mesecons_extrawires:vertical_off",
 	after_place_node = vertical_update,
 	after_dig_node = vertical_update
 },{
 	tiles = {"mesecons_wire_off.png"},
-	groups = {dig_immediate=2}, --MFF
+	groups = {dig_immediate=3},
 	mesecons = {conductor = {
 		state = mesecon.state.off,
 		onstate = "mesecons_extrawires:vertical_on",
@@ -98,7 +99,7 @@ mesecon.register_node("mesecons_extrawires:vertical", {
 	}}
 },{
 	tiles = {"mesecons_wire_on.png"},
-	groups = {dig_immediate=2, not_in_creative_inventory=1}, --MFF
+	groups = {dig_immediate=3, not_in_creative_inventory=1},
 	mesecons = {conductor = {
 		state = mesecon.state.on,
 		offstate = "mesecons_extrawires:vertical_off",
@@ -113,9 +114,10 @@ mesecon.register_node("mesecons_extrawires:vertical_top", {
 	walkable = false,
 	paramtype = "light",
 	sunlight_propagates = true,
-	groups = {dig_immediate=2, not_in_creative_inventory=1}, --MFF
+	groups = {dig_immediate=3, not_in_creative_inventory=1},
 	selection_box = top_box,
 	node_box = top_box,
+	on_rotate = false,
 	is_vertical_conductor = true,
 	drop = "mesecons_extrawires:vertical_off",
 	after_place_node = vertical_update,
@@ -143,9 +145,10 @@ mesecon.register_node("mesecons_extrawires:vertical_bottom", {
 	walkable = false,
 	paramtype = "light",
 	sunlight_propagates = true,
-	groups = {dig_immediate = 2, not_in_creative_inventory = 1}, --MFF
+	groups = {dig_immediate = 3, not_in_creative_inventory = 1},
 	selection_box = bottom_box,
 	node_box = bottom_box,
+	on_rotate = false,
 	is_vertical_conductor = true,
 	drop = "mesecons_extrawires:vertical_off",
 	after_place_node = vertical_update,

mesecons_fpga/depends.txt

@@ -0,0 +1 @@
+mesecons

mesecons_fpga/doc/fpga/description.html

@@ -0,0 +1,5 @@
+FPGAs can be used to chain multiple logic gates together in a compact manner.
+They come with 4 I/O ports and 10 internal registers,
+which can then be connected with eachother to form logic circuits.<br />
+Supported gate types: <b>AND</b>, <b>OR</b>, <b>NOT</b>, <b>XOR</b>, <b>NAND</b>, <b>XNOR</b>, <b>Buffer</b> (=)<br />
+I/O ports: <b>A B C D</b>; Registers: numbered <b>0</b> to <b>9</b>

mesecons_fpga/doc/programmer/description.html

@@ -0,0 +1,3 @@
+The FPGA programmer can be used to copy gate configurations from one FPGA to another.<br />
+Shift+Right-Click an FPGA to read its configuration and "remember" it.
+Left-click (punch) FPGAs to write the saved configuration to them.

mesecons_fpga/init.lua

@@ -0,0 +1,375 @@
+local plg = {}
+plg.rules = {}
+
+local lcore = dofile(minetest.get_modpath(minetest.get_current_modname()) .. "/logic.lua")
+dofile(minetest.get_modpath(minetest.get_current_modname()) .. "/tool.lua")(plg)
+
+
+plg.register_nodes = function(template)
+	-- each loop is for one of the 4 IO ports
+	for a = 0, 1 do
+	for b = 0, 1 do
+	for c = 0, 1 do
+	for d = 0, 1 do
+		local ndef = table.copy(template)
+		local nodename = "mesecons_fpga:fpga"
+				.. tostring(d) .. tostring(c) .. tostring(b) .. tostring(a)
+
+		-- build top texture string
+		local texture = "jeija_fpga_top.png"
+		if a == 1 then texture = texture .. "^jeija_microcontroller_LED_A.png" end
+		if b == 1 then texture = texture .. "^jeija_microcontroller_LED_B.png" end
+		if c == 1 then texture = texture .. "^jeija_microcontroller_LED_C.png" end
+		if d == 1 then texture = texture .. "^jeija_microcontroller_LED_D.png" end
+		ndef.tiles[1] = texture
+		ndef.inventory_image = texture
+
+		if (a + b + c + d) > 0 then
+			ndef.groups["not_in_creative_inventory"] = 1
+		end
+
+		-- interaction with mesecons (input / output)
+		local rules_out = {}
+		if a == 1 then table.insert(rules_out, {x = -1, y = 0, z =  0}) end
+		if b == 1 then table.insert(rules_out, {x =  0, y = 0, z =  1}) end
+		if c == 1 then table.insert(rules_out, {x =  1, y = 0, z =  0}) end
+		if d == 1 then table.insert(rules_out, {x =  0, y = 0, z = -1}) end
+		plg.rules[nodename] = rules_out
+
+		local rules_in = {}
+		if a == 0 then table.insert(rules_in, {x = -1, y = 0, z =  0}) end
+		if b == 0 then table.insert(rules_in, {x =  0, y = 0, z =  1}) end
+		if c == 0 then table.insert(rules_in, {x =  1, y = 0, z =  0}) end
+		if d == 0 then table.insert(rules_in, {x =  0, y = 0, z = -1}) end
+		ndef.mesecons.effector.rules = rules_in
+
+		if (a + b + c + d) > 0 then
+			ndef.mesecons.receptor = {
+				state = mesecon.state.on,
+				rules = rules_out,
+			}
+		end
+
+		minetest.register_node(nodename, ndef)
+	end
+	end
+	end
+	end
+end
+
+plg.register_nodes({
+	description = "FPGA",
+	drawtype = "nodebox",
+	tiles = {
+		"", -- replaced later
+		"jeija_microcontroller_bottom.png",
+		"jeija_fpga_sides.png",
+		"jeija_fpga_sides.png",
+		"jeija_fpga_sides.png",
+		"jeija_fpga_sides.png"
+	},
+	inventory_image = "", -- replaced later
+	sunlight_propagates = true,
+	paramtype = "light",
+	walkable = true,
+	groups = {dig_immediate = 2, mesecon = 3},
+	drop = "mesecons_fpga:fpga0000",
+	selection_box = {
+		type = "fixed",
+		fixed = { -8/16, -8/16, -8/16, 8/16, -5/16, 8/16 },
+	},
+	node_box = {
+		type = "fixed",
+		fixed = {
+			{ -8/16, -8/16, -8/16, 8/16, -7/16, 8/16 }, -- bottom slab
+			{ -5/16, -7/16, -5/16, 5/16, -6/16, 5/16 }, -- circuit board
+			{ -3/16, -6/16, -3/16, 3/16, -5/16, 3/16 }, -- IC
+		}
+	},
+	on_construct = function(pos)
+		local meta = minetest.get_meta(pos)
+		local is = { {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {} }
+
+		meta:set_string("instr", lcore.serialize(is))
+		meta:set_int("valid", 0)
+		meta:set_string("formspec", plg.to_formspec_string(is))
+		meta:set_string("infotext", "FPGA")
+	end,
+	on_receive_fields = function(pos, formname, fields, sender)
+		if fields.program == nil then return end -- we only care when the user clicks "Program"
+		local meta = minetest.get_meta(pos)
+		local is = plg.from_formspec_fields(fields)
+
+		meta:set_string("instr", lcore.serialize(is))
+		plg.update_formspec(pos, is)
+	end,
+	sounds = default.node_sound_stone_defaults(),
+	mesecons = {
+		effector = {
+			rules = {}, -- replaced later
+			action_change = function(pos, node, rule, newstate)
+				plg.ports_changed(pos, rule, newstate)
+				plg.update(pos)
+			end
+		}
+	},
+	after_dig_node = function(pos, node)
+		mesecon.receptor_off(pos, plg.rules[node.name])
+	end,
+})
+
+
+plg.to_formspec_string = function(is)
+	local function dropdown_op(x, y, name, val)
+		local s = "dropdown[" .. tostring(x) .. "," .. tostring(y) .. ";"
+				.. "0.75,0.5;" .. name .. ";" -- the height seems to be ignored?
+		s = s .. " ,A,B,C,D,0,1,2,3,4,5,6,7,8,9;"
+		if val == nil then
+			s = s .. "0" -- actually selects no field at all
+		elseif val.type == "io" then
+			local mapping = {
+				["A"] = 1,
+				["B"] = 2,
+				["C"] = 3,
+				["D"] = 4,
+			}
+			s = s .. tostring(1 + mapping[val.port])
+		else -- "reg"
+			s = s .. tostring(6 + val.n)
+		end
+		return s .. "]"
+	end
+	local function dropdown_action(x, y, name, val)
+		local s = "dropdown[" .. tostring(x) .. "," .. tostring(y) .. ";"
+				.. "1.125,0.5;" .. name .. ";" -- the height seems to be ignored?
+		s = s .. " , AND,  OR, NOT, XOR,NAND,   =,XNOR;"
+		if val == nil then
+			return s .. "0]" -- actually selects no field at all
+		end
+		local mapping = {
+			["and"] = 1,
+			["or"] = 2,
+			["not"] = 3,
+			["xor"] = 4,
+			["nand"] = 5,
+			["buf"] = 6,
+			["xnor"] = 7,
+		}
+		return s .. tostring(1 + mapping[val]) .. "]"
+	end
+	local s = "size[9,9]"..
+		"label[3.4,-0.15;FPGA gate configuration]"..
+		"button_exit[7,7.5;2,2.5;program;Program]"..
+		"box[4.2,0.5;0.03,7;#ffffff]"..
+		"label[0.25,0.25;op. 1]"..
+		"label[1.0,0.25;gate type]"..
+		"label[2.125,0.25;op. 2]"..
+		"label[3.15,0.25;dest]"..
+		"label[4.5,0.25;op. 1]"..
+		"label[5.25,0.25;gate type]"..
+		"label[6.375,0.25;op. 2]"..
+		"label[7.4,0.25;dest]"
+	local x = 1 - 0.75
+	local y = 1 - 0.25
+	for i = 1, 14 do
+		local cur = is[i]
+		s = s .. dropdown_op    (x      , y, tostring(i).."op1", cur.op1)
+		s = s .. dropdown_action(x+0.75 , y, tostring(i).."act", cur.action)
+		s = s .. dropdown_op    (x+1.875, y, tostring(i).."op2", cur.op2)
+		s = s .. "label[" .. tostring(x+2.625) .. "," .. tostring(y+0.1) .. "; ->]"
+		s = s .. dropdown_op    (x+2.9  , y, tostring(i).."dst", cur.dst)
+		y = y + 1
+
+		if i == 7 then
+			x = 4.5
+			y = 1 - 0.25
+		end
+	end
+	return s
+end
+
+plg.from_formspec_fields = function(fields)
+	local function read_op(s)
+		if s == nil or s == " " then
+			return nil
+		elseif s == "A" or s == "B" or s == "C" or s == "D" then
+			return {type = "io", port = s}
+		else
+			return {type = "reg", n = tonumber(s)}
+		end
+	end
+	local function read_action(s)
+		if s == nil or s == " " then
+			return nil
+		end
+		local mapping = {
+			["AND"] = "and",
+			["OR"] = "or",
+			["NOT"] = "not",
+			["XOR"] = "xor",
+			["NAND"] = "nand",
+			["="] = "buf",
+			["XNOR"] = "xnor",
+		}
+		s = s:gsub("^%s*", "") -- remove leading spaces
+		return mapping[s]
+	end
+	local is = {}
+	for i = 1, 14 do
+		local cur = {}
+		cur.op1 = read_op(fields[tonumber(i) .. "op1"])
+		cur.action = read_action(fields[tonumber(i) .. "act"])
+		cur.op2 = read_op(fields[tonumber(i) .. "op2"])
+		cur.dst = read_op(fields[tonumber(i) .. "dst"])
+		is[#is + 1] = cur
+	end
+	return is
+end
+
+plg.update_formspec = function(pos, is)
+	if type(is) == "string" then -- serialized string
+		is = lcore.deserialize(is)
+	end
+	local meta = minetest.get_meta(pos)
+	local form = plg.to_formspec_string(is)
+
+	local err = lcore.validate(is)
+	if err == nil then
+		meta:set_int("valid", 1)
+		meta:set_string("infotext", "FPGA (functional)")
+	else
+		meta:set_int("valid", 0)
+		meta:set_string("infotext", "FPGA")
+		local fmsg = minetest.colorize("#ff0000", minetest.formspec_escape(err.msg))
+		form = form .. plg.red_box_around(err.i) ..
+			"label[0.25,8.25;The gate configuration is erroneous in the marked area:]"..
+			"label[0.25,8.5;" .. fmsg .. "]"
+	end
+
+	meta:set_string("formspec", form)
+
+	-- reset ports and run programmed logic
+	plg.setports(pos, false, false, false, false)
+	plg.update(pos)
+end
+
+plg.red_box_around = function(i)
+	local x, y
+	if i > 7 then
+		x = 4.5
+		y = 0.75 + (i - 8)
+	else
+		x = 0.25
+		y = 0.75 + (i - 1)
+	end
+	return string.format("box[%f,%f;3.8,0.8;#ff0000]", x-0.1, y-0.05)
+end
+
+
+plg.update = function(pos)
+	local meta = minetest.get_meta(pos)
+	if meta:get_int("valid") ~= 1 then
+		return
+	end
+
+	local is = lcore.deserialize(meta:get_string("instr"))
+	local A, B, C, D = plg.getports(pos)
+	A, B, C, D = lcore.interpret(is, A, B, C, D)
+	plg.setports(pos, A, B, C, D)
+end
+
+plg.ports_changed = function(pos, rule, newstate)
+	if rule == nil then return end
+	local meta = minetest.get_meta(pos)
+	local states
+
+	local s = meta:get_string("portstates")
+	if s == nil then
+		states = {false, false, false, false}
+	else
+		states = {
+			s:sub(1, 1) == "1",
+			s:sub(2, 2) == "1",
+			s:sub(3, 3) == "1",
+			s:sub(4, 4) == "1",
+		}
+	end
+
+	-- trick to transform rules (see register_node) into port number
+	local portno = ({4, 1, nil, 3, 2})[3 + rule.x + 2*rule.z]
+	states[portno] = (newstate == "on")
+
+	meta:set_string("portstates",
+			(states[1] and "1" or "0") .. (states[2] and "1" or "0") ..
+			(states[3] and "1" or "0") .. (states[4] and "1" or "0")
+	)
+end
+
+plg.getports = function(pos) -- gets merged states of INPUT & OUTPUT
+	local sin, sout
+
+	local s = minetest.get_meta(pos):get_string("portstates")
+	if s == nil then
+		sin = {false, false, false, false}
+	else
+		sin = {
+			s:sub(1, 1) == "1",
+			s:sub(2, 2) == "1",
+			s:sub(3, 3) == "1",
+			s:sub(4, 4) == "1",
+		}
+	end
+
+	local name = minetest.get_node(pos).name
+	assert(name:find("mesecons_fpga:fpga") == 1)
+	local off = #"mesecons_fpga:fpga"
+	sout = {
+		name:sub(off+4, off+4) == "1",
+		name:sub(off+3, off+3) == "1",
+		name:sub(off+2, off+2) == "1",
+		name:sub(off+1, off+1) == "1",
+	}
+
+	return unpack({
+		sin[1] or sout[1],
+		sin[2] or sout[2],
+		sin[3] or sout[3],
+		sin[4] or sout[4],
+	})
+end
+
+plg.setports = function(pos, A, B, C, D) -- sets states of OUTPUT
+	local base = "mesecons_fpga:fpga"
+
+	local name = base
+			.. (D and "1" or "0") .. (C and "1" or "0")
+			.. (B and "1" or "0") .. (A and "1" or "0")
+	minetest.swap_node(pos, {name = name, param2 = minetest.get_node(pos).param2})
+
+	if A ~= nil then
+		local ru = plg.rules[base .. "0001"]
+		if A then mesecon.receptor_on(pos, ru) else mesecon.receptor_off(pos, ru) end
+	end
+	if B ~= nil then
+		local ru = plg.rules[base .. "0010"]
+		if B then mesecon.receptor_on(pos, ru) else mesecon.receptor_off(pos, ru) end
+	end
+	if C ~= nil then
+		local ru = plg.rules[base .. "0100"]
+		if C then mesecon.receptor_on(pos, ru) else mesecon.receptor_off(pos, ru) end
+	end
+	if D ~= nil then
+		local ru = plg.rules[base .. "1000"]
+		if D then mesecon.receptor_on(pos, ru) else mesecon.receptor_off(pos, ru) end
+	end
+end
+
+
+minetest.register_craft({
+	output = "mesecons_fpga:fpga0000 2",
+	recipe = {
+		{'group:mesecon_conductor_craftable', 'group:mesecon_conductor_craftable'},
+		{'mesecons_materials:silicon', 'mesecons_materials:silicon'},
+		{'group:mesecon_conductor_craftable', 'group:mesecon_conductor_craftable'},
+	}
+})

mesecons_fpga/logic.lua

@@ -0,0 +1,210 @@
+local lg = {}
+
+-- (de)serialize
+lg.serialize = function(t)
+	local function _op(t)
+		if t == nil then
+			return " "
+		elseif t.type == "io" then
+			return t.port
+		else -- t.type == "reg"
+			return tostring(t.n)
+		end
+	end
+	local function _action(s)
+		if s == nil then
+			return " "
+		end
+		local mapping = {
+			["and"] = "&",
+			["or"] = "|",
+			["not"] = "~",
+			["xor"] = "^",
+			["nand"] = "?", --dunno
+			["buf"] = "_",
+			["xnor"] = "=",
+		}
+		return mapping[s]
+	end
+
+	local s = ""
+	for i = 1, 14 do
+		local cur = t[i]
+		if next(cur) ~= nil then
+			s = s .. _op(cur.op1) .. _action(cur.action) .. _op(cur.op2) .. _op(cur.dst)
+		end
+		s = s .. "/"
+	end
+	return s
+end
+
+lg.deserialize = function(s)
+	local function _op(c)
+		if c == "A" or c == "B" or c == "C" or c == "D" then
+			return {type = "io", port = c}
+		elseif c == " " then
+			return nil
+		else
+			return {type = "reg", n = tonumber(c)}
+		end
+	end
+	local function _action(c)
+		local mapping = {
+			["&"] = "and",
+			["|"] = "or",
+			["~"] = "not",
+			["^"] = "xor",
+			["?"] = "nand",
+			["_"] = "buf",
+			["="] = "xnor",
+			[" "] = nil,
+		}
+		return mapping[c]
+	end
+
+	local ret = {}
+	for part in s:gmatch("(.-)/") do
+		local parsed
+		if part == "" then
+			parsed = {}
+		else
+			parsed = {
+				action = _action( part:sub(2,2) ),
+				op1 = _op( part:sub(1,1) ),
+				op2 = _op( part:sub(3,3) ),
+				dst = _op( part:sub(4,4) ),
+			}
+		end
+		ret[#ret + 1] = parsed
+	end
+	-- More than 14 instructions (write to all 10 regs + 4 outputs)
+	-- will not pass the write-once requirement of the validator
+	assert(#ret == 14)
+	return ret
+end
+
+-- validation
+lg.validate_single = function(t, i)
+	local function is_reg_written_to(t, n, max)
+		for i = 1, max-1 do
+			if next(t[i]) ~= nil
+					and t[i].dst and t[i].dst.type == "reg"
+					and t[i].dst.n == n then
+				return true
+			end
+		end
+		return false
+	end
+	local function compare_op(t1, t2, allow_same_io)
+		if t1 == nil or t2 == nil then
+			return false
+		elseif t1.type ~= t2.type then
+			return false
+		end
+		if t1.type == "reg" and t1.n == t2.n then
+			return true
+		elseif t1.type == "io" and t1.port == t2.port then
+			return not allow_same_io
+		end
+		return false
+	end
+	local elem = t[i]
+	-- check for completeness
+	if elem.action == nil then
+		return {i = i, msg = "Gate type required"}
+	elseif elem.action == "not" or elem.action == "buf" then
+		if elem.op1 ~= nil or elem.op2 == nil or elem.dst == nil then
+			return {i = i, msg = "Second operand (only) and destination required"}
+		end
+	else
+		if elem.op1 == nil or elem.op2 == nil or elem.dst == nil then
+			return {i = i, msg = "Operands and destination required"}
+		end
+	end
+	-- check whether operands/destination are identical
+	if compare_op(elem.op1, elem.op2) then
+		return {i = i, msg = "Operands cannot be identical"}
+	end
+	if compare_op(elem.op1, elem.dst, true) or compare_op(elem.op2, elem.dst, true) then
+		return {i = i, msg = "Destination and operands must be different"}
+	end
+	-- check whether operands point to defined registers
+	if elem.op1 ~= nil and elem.op1.type == "reg"
+			and not is_reg_written_to(t, elem.op1.n, i) then
+		return {i = i, msg = "First operand is undefined register"}
+	end
+	if elem.op2.type == "reg" and not is_reg_written_to(t, elem.op2.n, i) then
+		return {i = i, msg = "Second operand is undefined register"}
+	end
+	-- check whether destination points to undefined register
+	if elem.dst.type == "reg" and is_reg_written_to(t, elem.dst.n, i) then
+		return {i = i, msg = "Destination is already used register"}
+	end
+
+	return nil
+end
+
+lg.validate = function(t)
+	for i = 1, 14 do
+		if next(t[i]) ~= nil then
+			local r = lg.validate_single(t, i)
+			if r ~= nil then
+				return r
+			end
+		end
+	end
+	return nil
+end
+
+-- interpreter
+lg.interpret = function(t, a, b, c, d)
+	local function _action(s, v1, v2)
+		if s == "and" then
+			return v1 and v2
+		elseif s == "or" then
+			return v1 or v2
+		elseif s == "not" then
+			return not v2
+		elseif s == "xor" then
+			return v1 ~= v2
+		elseif s == "nand" then
+			return not (v1 and v2)
+		elseif s == "buf" then
+			return v2
+		else -- s == "xnor"
+			return v1 == v2
+		end
+	end
+	local function _op(t, regs, io_in)
+		if t.type == "reg" then
+			return regs[t.n]
+		else -- t.type == "io"
+			return io_in[t.port]
+		end
+	end
+
+	local io_in = {A=a, B=b, C=c, D=d}
+	local regs = {}
+	local io_out = {}
+	for i = 1, 14 do
+		local cur = t[i]
+		if next(cur) ~= nil then
+			local v1, v2
+			if cur.op1 ~= nil then
+				v1 = _op(cur.op1, regs, io_in)
+			end
+			v2 = _op(cur.op2, regs, io_in)
+
+			local result = _action(cur.action, v1, v2)
+
+			if cur.dst.type == "reg" then
+				regs[cur.dst.n] = result
+			else -- cur.dst.type == "io"
+				io_out[cur.dst.port] = result
+			end
+		end
+	end
+	return io_out.A, io_out.B, io_out.C, io_out.D
+end
+
+return lg

mesecons_fpga/tool.lua

@@ -0,0 +1,62 @@
+return function(plg)
+
+
+minetest.register_tool("mesecons_fpga:programmer", {
+	description = "FPGA Programmer",
+	inventory_image = "jeija_fpga_programmer.png",
+	stack_max = 1,
+	on_place = function(itemstack, placer, pointed_thing)
+		if pointed_thing.type ~= "node" then
+			return itemstack
+		end
+
+		local pos = pointed_thing.under
+		if minetest.get_node(pos).name:find("mesecons_fpga:fpga") ~= 1 then
+			return itemstack
+		end
+
+		local meta = minetest.get_meta(pos)
+		if meta:get_string("instr") == "//////////////" then
+			minetest.chat_send_player(placer:get_player_name(), "This FPGA is unprogrammed.")
+			return itemstack
+		end
+		itemstack:set_metadata(meta:get_string("instr"))
+		minetest.chat_send_player(placer:get_player_name(), "FPGA gate configuration was successfully copied!")
+		
+		return itemstack
+	end,
+	on_use = function(itemstack, user, pointed_thing)
+		if pointed_thing.type ~= "node" then
+			return itemstack
+		end
+
+		local pos = pointed_thing.under
+		if minetest.get_node(pos).name:find("mesecons_fpga:fpga") ~= 1 then
+			return itemstack
+		end
+
+		local imeta = itemstack:get_metadata()
+		if imeta == "" then
+			minetest.chat_send_player(user:get_player_name(), "Use shift+right-click to copy a gate configuration first.")
+			return itemstack
+		end
+
+		local meta = minetest.get_meta(pos)
+		meta:set_string("instr", imeta)
+		plg.update_formspec(pos, imeta)
+		minetest.chat_send_player(user:get_player_name(), "Gate configuration was successfully written to FPGA!")
+
+		return itemstack
+	end
+})
+
+minetest.register_craft({
+	output = "mesecons_fpga:programmer",
+	recipe = {
+		{'group:mesecon_conductor_craftable'},
+		{'mesecons_materials:silicon'},
+	}
+})
+
+
+end

mesecons_gates/init.lua

@@ -54,7 +54,7 @@ local function update_gate(pos, node, link, newstate)
 	end
 end
 
-function register_gate(name, inputnumber, assess, recipe)
+local function register_gate(name, inputnumber, assess, recipe)
 	local get_inputrules = inputnumber == 2 and gate_get_input_rules_twoinputs or
 		gate_get_input_rules_oneinput
 	local description = "Mesecons Logic Gate: "..name