Fix crash in comparitor code, add input rule processing

mods/ITEMS/REDSTONE/mcl_comparators/init.lua

@@ -100,6 +100,8 @@ end
 
 function mod.read_inventory(inv, inv_name)
 	local stacks = inv:get_list(inv_name)
+	if not stacks then return 0 end
+
 	local count = 0
 	for i=1,#stacks do
 		count = count + ( stacks[i]:get_count() / stacks[i]:get_stack_max() )

mods/ITEMS/REDSTONE/vl_redstone/init.lua

@@ -16,6 +16,7 @@ local minetest_swap_node = minetest.swap_node
 local vector_add = vector.add
 local vector_to_string = vector.to_string
 local vector_from_string = vector.from_string
+local math_floor = math.floor
 
 -- Constants
 local REDSTONE_POWER_META = modname .. ".power"
@@ -23,46 +24,145 @@ local REDSTONE_POWER_META_SOURCE = REDSTONE_POWER_META.."."
 
 local multipower_cache = {}
 
+local function hash_from_direction(dir)
+	return 9 * (dir.x + 1) + 3 * (dir.y + 1) + dir.z + 1
+end
+local function direction_from_hash(dir_hash)
+	local x = math_floor(dir_hash / 9) - 1
+	local y = math_floor((dir_hash % 9) / 3 ) - 1
+	local z = dir_hash % 3 - 1
+	return vector.new(x,y,z)
+end
+local DIR_HASH_ZERO = hash_from_direction(vector.zero())
+print("DIR_HASH_ZERO="..tostring(DIR_HASH_ZERO))
+
+local function get_input_rules_hash(mesecons, input_rules)
+	-- Skip build if already built
+	local redstone = mesecons._vl_redtone or {}
+	mesecons._vl_redstone = redstone
+	if redstone.input_rules_hash then return redstone.input_rules_hash end
+
+	-- Build the rules
+	local input_rules_hash = {}
+	redstone.input_rules_hash = input_rules_hash
+	for i=1,#input_rules do
+		input_rules_hash[hash_from_direction(input_rules[i])] = true
+	end
+
+	return input_rules_hash
+end
+
 local function get_node_multipower_data(pos, no_create)
 	local hash = minetest_hash_node_pos(pos)
 	local node_multipower = multipower_cache[hash]
 	if not node_multipower and not no_create then
 		local meta = minetest_get_meta(pos)
-		node_multipower = minetest_deserialize(meta:get_string("vl_redstone.multipower")) or {sources={}}
+		node_multipower = minetest_deserialize(meta:get_string("vl_redstone.multipower"))
+		if not node_multipower or node_multipower.version ~= 1 then
+			node_multipower = {
+				version = 1,
+				sources={}
+			}
+		end
 		multipower_cache[hash] = node_multipower
 	end
 	return node_multipower
 end
 
+local function calculate_driven_strength(pos, input_rules_hash)
+	local dir_hash = dir and hash_from_direction(dir)
+	local node_multipower = get_node_multipower_data(pos)
+	local strength = 0
+	local strongest_direction_hash = nil
+	local sources = node_multipower.sources
+	input_rules_hash = input_rules_hash or {}
+
+	print("in update_node(pos="..vector_to_string(pos)..") node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
+	for pos_hash,data in pairs(sources) do
+		local source_strength = data[1]
+		local dirs = data[2]
+		--print("data="..dump(data))
+		--print("\t"..vector_to_string(pos)..".source["..vector_to_string(minetest_get_position_from_hash(pos_hash)).."] = "..tostring(strength))
+
+		-- Filter by specified direction
+		local match = false
+		if not dir_hash then
+			match = true
+		else
+			for i=1,#dirs do
+				match = match or input_rules_hash[dirs[i]]
+			end
+		end
+
+		print("match="..tostring(match)..",source_strength="..tostring(source_strength))
+
+		-- Update strength and track which direction the strongest power is coming from
+		if match and source_strength >= strength then
+			strength = source_strength
+			if #dirs ~= 0 then
+				strongest_direction_hash = dirs[1]
+			end
+		end
+	end
+
+	return strength,strongest_direction_hash
+end
+
 local function update_node(pos)
 	local node = mcl_util_force_get_node(pos)
 	local nodedef = minetest.registered_nodes[node.name]
 
-	-- Only do this processing of signal sinks
+	-- Only do this processing of signal sinks and conductors
-	if not nodedef.mesecons then return end
+	local nodedef_mesecons = nodedef.mesecons
+	if not nodedef_mesecons then return end
 
-	-- Calculate the maximum power feeding into this node
+	print("Running update_node(pos="..vector_to_string(pos)..")")
-	local node_multipower = get_node_multipower_data(pos)
+
-	local strength = 0
+	-- Get input rules
-	local sources = node_multipower.sources
+	local input_rules = nil
-	--print("in update_node(pos="..vector_to_string(pos)..") node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
+	if nodedef_mesecons.conductor then
-	for pos_hash,source_strength in pairs(sources) do
+		input_rules = nodedef_mesecons.conductor.rules
-		--print("\t"..vector_to_string(pos)..".source["..vector_to_string(minetest_get_position_from_hash(pos_hash)).."] = "..tostring(strength))
+	elseif nodedef_mesecons.effector then
-		if source_strength > strength then strength = source_strength end
+		input_rules = nodedef_mesecons.effector.rules
+	else
+		-- No input rules, can't act
+		print("Unable to find input rules for "..node.name..": mesecons="..dump(nodedef_mesecons))
+		return
 	end
 
+	-- Calculate the maximum power feeding into this node
+	local input_rules_hash = get_input_rules_hash(nodedef_mesecons, input_rules)
+	print("input_rules_hash="..dump(input_rules_hash)..", input_rules="..dump(input_rules))
+	local strength,dir_hash = calculate_driven_strength(pos, input_rules_hash)
+	print("strength="..tostring(strength)..",dir_hash="..tostring(dir_hash))
+
 	-- Don't do any processing inf the actual strength at this node has changed
+	local node_multipower = get_node_multipower_data(pos)
 	local last_strength = node_multipower.strength or 0
-	--print("At "..vector_to_string(pos).." strength="..tostring(strength)..",last_strength="..tostring(last_strength))
+	print("At "..vector_to_string(pos).." strength="..tostring(strength)..",last_strength="..tostring(last_strength))
 	if last_strength == strength then return end
 
+	-- Determine the input rule that the strength is coming from (for mesecons compatibility; there are mods that depend on it)
+	local rule = nil
+	for i = 1,#input_rules do
+		local input_rule = input_rules[i]
+		local input_rule_hash = hash_from_direction(input_rule)
+		if dir_hash == input_rule_hash then
+			rule = input_rule
+			break
+		end
+	end
+	if not rule then
+		print("No rule found")
+		return
+	else
+		print("rule="..dump(rule))
+	end
+
 	-- Update the state
 	node_multipower.strength = strength
 
-	-- TODO: determine the input rule that the strength is coming from (for mesecons compatibility; there are mods that depend on it)
+	local sink = nodedef_mesecons.effector
-	local rule = nil
-
-	local sink = nodedef.mesecons.effector
 	if sink then
 		local new_node_name = nil
 		--print("Updating "..node.name.." at "..vector_to_string(pos).."("..tostring(last_strength).."->"..tostring(strength)..")")
@@ -87,7 +187,7 @@ local function update_node(pos)
 			end
 		end
 
-		-- TODO: handle signal level change notification
+		-- handle signal level change notification
 		local hook = sink.action_change
 		if hook then
 			mcl_util_call_safe(nil, hook, {pos, node, rule, strength})
@@ -104,7 +204,7 @@ local function update_node(pos)
 		return
 	end
 
-	local conductor = nodedef.mesecons.conductor
+	local conductor = nodedef_mesecons.conductor
 	if conductor then
 		-- Figure out if the node name changes based on the new state
 		local new_node_name = nil
@@ -118,7 +218,7 @@ local function update_node(pos)
 
 		-- Update the node
 		if new_node_name and new_node_name ~= node.name then
-			--[[
+			---[[
 			print("Changing "..vector_to_string(pos).." from "..node.name.." to "..new_node_name..
 			    ", strength="..tostring(strength)..",last_strength="..tostring(last_strength))
 			print("node.name="..node.name..
@@ -169,10 +269,13 @@ local function get_positions_from_node_rules(pos, rules_type, list, powered)
 
 	-- Convert to absolute positions
 	for i=1,#rules do
-		local next_pos = vector_add(pos, rules[i])
+		local rule = rules[i]
+		local next_pos = vector_add(pos, rule)
 		local next_pos_hash = minetest_hash_node_pos(next_pos)
 		--print("\tnext: "..next_pos_str..", prev="..tostring(list[next_pos_str]))
-		list[next_pos_hash] = true
+		local dirs = list[next_pos_hash] or {}
+		list[next_pos_hash] = dirs
+		dirs[hash_from_direction(rule)] = true
 
 		-- Power solid blocks
 		if rules[i].spread then
@@ -206,7 +309,7 @@ vl_scheduler.register_function("vl_redstone:flow_power",function(task, source_po
 		local strength = source_strength - (i - 1)
 		if strength < 0 then strength = 0 end
 
-		for pos_hash,dir in pairs(list) do
+		for pos_hash,dir_list in pairs(list) do
 			--print("Processing "..pos_str)
 
 			if not processed[pos_hash] then
@@ -216,11 +319,17 @@ vl_scheduler.register_function("vl_redstone:flow_power",function(task, source_po
 
 				-- Update node power directly
 				local node_multipower = get_node_multipower_data(pos)
-				--local old_strength = node_multipower.sources[source_pos_hash] or 0
+				local old_data = node_multipower.sources[source_pos_hash]
-				--print("Changing "..vector.to_string(pos)..".source["..vector_to_string(source_pos).."] from "..tostring(old_strength).." to "..tostring(strength))
+				local old_strength = old_data and old_data[1] or 0
-				--print("\tBefore node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
+				print("Changing "..vector.to_string(pos)..".source["..vector_to_string(source_pos).."] from "..tostring(old_strength).." to "..tostring(strength))
-				node_multipower.sources[source_pos_hash] = strength
+				print("\tBefore node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
-				--print("\tAfter  node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
+				print("\tdir_list="..dump(dir_list))
+				local dirs = {}
+				for k,_ in pairs(dir_list) do
+					dirs[#dirs+1] = k
+				end
+				node_multipower.sources[source_pos_hash] = {strength,dirs}
+				print("\tAfter  node_multipower("..tostring(node_multipower)..")="..dump(node_multipower))
 
 				-- handle spread
 				get_positions_from_node_rules(pos, "conductor", next_list, powered)