From 3f75c06a3bf80a4c50ccb0991b3664c491c0d523 Mon Sep 17 00:00:00 2001 From: DS Date: Thu, 25 Mar 2021 16:53:51 +0100 Subject: [PATCH] Improve performance of mesecon.turnon and mesecon.turnoff (#556) --- mesecons/fifo_queue.lua | 62 +++++++++++++++++++++++++++++++++++++++++ mesecons/internal.lua | 48 ++++++++++++++++++++----------- 2 files changed, 93 insertions(+), 17 deletions(-) create mode 100644 mesecons/fifo_queue.lua diff --git a/mesecons/fifo_queue.lua b/mesecons/fifo_queue.lua new file mode 100644 index 0000000..a71c71b --- /dev/null +++ b/mesecons/fifo_queue.lua @@ -0,0 +1,62 @@ + +-- a simple first-in-first-out queue +-- very similar to the one in https://github.com/minetest/minetest/pull/7683 + +local fifo_queue = {} + +local metatable = {__index = fifo_queue} + +-- creates a new empty queue +function fifo_queue.new() + local q = {n_in = 0, n_out = 0, i_out = 1, buf_in = {}, buf_out = {}} + setmetatable(q, metatable) + return q +end + +-- adds an element to the queue +function fifo_queue.add(self, v) + local n = self.n_in + 1 + self.n_in = n + self.buf_in[n] = v +end + +-- removes and returns the next element, or nil of empty +function fifo_queue.take(self) + local i_out = self.i_out + if i_out <= self.n_out then + local v = self.buf_out[i_out] + self.i_out = i_out + 1 + self.buf_out[i_out] = true + return v + end + + -- buf_out is empty, try to swap + self.i_out = 1 + self.n_out = 0 + if self.n_in == 0 then + return nil -- empty + end + + -- swap + self.n_out = self.n_in + self.n_in = 0 + self.buf_out, self.buf_in = self.buf_in, self.buf_out + + local v = self.buf_out[1] + self.i_out = 2 + self.buf_out[1] = true + return v +end + +-- returns whether the queue is empty +function fifo_queue.is_empty(self) + return self.n_out == self.i_out + 1 and self.n_in == 0 +end + +-- returns stuff for iteration in a for loop, like pairs +-- adding new elements while iterating is no problem +function fifo_queue.iter(self) + return fifo_queue.take, self, nil +end + +return fifo_queue diff --git a/mesecons/internal.lua b/mesecons/internal.lua index 044e3bf..93eccf9 100644 --- a/mesecons/internal.lua +++ b/mesecons/internal.lua @@ -11,7 +11,7 @@ -- RECEPTORS -- mesecon.is_receptor(nodename) --> Returns true if nodename is a receptor --- mesecon.is_receptor_on(nodename --> Returns true if nodename is an receptor with state = mesecon.state.on +-- mesecon.is_receptor_on(nodename) --> Returns true if nodename is an receptor with state = mesecon.state.on -- mesecon.is_receptor_off(nodename) --> Returns true if nodename is an receptor with state = mesecon.state.off -- mesecon.receptor_get_rules(node) --> Returns the rules of the receptor (mesecon.rules.default if none specified) @@ -46,6 +46,8 @@ -- mesecon.rotate_rules_down(rules) -- These functions return rules that have been rotated in the specific direction +local fifo_queue = dofile(minetest.get_modpath("mesecons").."/fifo_queue.lua") + -- General function mesecon.get_effector(nodename) if minetest.registered_nodes[nodename] @@ -371,32 +373,39 @@ end -- 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 frontiers = fifo_queue.new() + frontiers:add({pos = pos, link = link}) + local pos_can_be_skipped = {} local depth = 1 - while frontiers[1] do - local f = table.remove(frontiers, 1) + for f in frontiers:iter() do local node = mesecon.get_node_force(f.pos) if not node then -- Area does not exist; do nothing + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true elseif mesecon.is_conductor_off(node, f.link) then local rules = mesecon.conductor_get_rules(node) -- 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 - table.insert(frontiers, {pos = np, link = l}) + if not pos_can_be_skipped[minetest.hash_node_position(np)] then + for _, l in ipairs(mesecon.rules_link_rule_all(f.pos, r)) do + frontiers:add({pos = np, link = l}) + end end end mesecon.swap_node_force(f.pos, mesecon.get_conductor_on(node, f.link)) + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true 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 mesecon.activate(f.pos, node, f.link, depth) end + else + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true end depth = depth + 1 end @@ -419,37 +428,40 @@ end -- depth = indicates order in which signals wire fired, higher is later -- } function mesecon.turnoff(pos, link) - local frontiers = {{pos = pos, link = link}} + local frontiers = fifo_queue.new() + frontiers:add({pos = pos, link = link}) local signals = {} + local pos_can_be_skipped = {} local depth = 1 - while frontiers[1] do - local f = table.remove(frontiers, 1) + for f in frontiers:iter() do local node = mesecon.get_node_force(f.pos) if not node then -- Area does not exist; do nothing + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true elseif mesecon.is_conductor_on(node, f.link) then local rules = mesecon.conductor_get_rules(node) for _, r in ipairs(mesecon.rule2meta(f.link, rules)) do local np = vector.add(f.pos, r) - -- Check if an onstate receptor is connected. If that is the case, - -- abort this turnoff process by returning false. `receptor_off` will - -- discard all the changes that we made in the voxelmanip: - for _, l in ipairs(mesecon.rules_link_rule_all_inverted(f.pos, r)) do + if not pos_can_be_skipped[minetest.hash_node_position(np)] then + -- Check if an onstate receptor is connected. If that is the case, + -- abort this turnoff process by returning false. `receptor_off` will + -- discard all the changes that we made in the voxelmanip: if mesecon.is_receptor_on(mesecon.get_node_force(np).name) then return false end - end - -- Call turnoff on neighbors - for _, l in ipairs(mesecon.rules_link_rule_all(f.pos, r)) do - table.insert(frontiers, {pos = np, link = l}) + -- Call turnoff on neighbors + for _, l in ipairs(mesecon.rules_link_rule_all(f.pos, r)) do + frontiers:add({pos = np, link = l}) + end end end mesecon.swap_node_force(f.pos, mesecon.get_conductor_off(node, f.link)) + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true elseif mesecon.is_effector(node.name) then table.insert(signals, { pos = f.pos, @@ -457,6 +469,8 @@ function mesecon.turnoff(pos, link) link = f.link, depth = depth }) + else + pos_can_be_skipped[minetest.hash_node_position(f.pos)] = true end depth = depth + 1 end