From b6aafedf25a2b8dd3bc598cc8a9b49de8fb3697f Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Mon, 17 Jun 2024 07:15:04 -0500
Subject: [PATCH 01/13] Fix space check function has_room() in
 mcl_mobs/spawning.lua so it allows spiderproofing

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index d47b2212f..1fb07247c 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -542,13 +542,20 @@ local function has_room(self,pos)
 		end
 	end
 	table.insert(nodes,"air")
-	local x = cb[4] - cb[1]
-	local y = cb[5] - cb[2]
-	local z = cb[6] - cb[3]
-	local r = math.ceil(x * y * z)
-	local p1 = vector.offset(pos,cb[1],cb[2],cb[3])
-	local p2 = vector.offset(pos,cb[4],cb[5],cb[6])
-	local n = #minetest.find_nodes_in_area(p1,p2,nodes) or 0
+
+	local p1 = vector.offset(pos,cb[1],cb[2] + 1,cb[3])
+	p1.x = math.floor(p1.x)
+	p1.y = math.floor(p1.y)
+	p1.z = math.floor(p1.z)
+
+	local p2 = vector.offset(p1,cb[4] - cb[1], cb[5] - cb[2], cb[6] - cb[3])
+	p2.x = math.floor(p2.x)
+	p2.y = math.floor(p2.y)
+	p2.z = math.floor(p2.z)
+
+	local r = (p2.x - p1.x + 1) * (p2.y - p1.y + 1) * (p2.z - p1.z + 1)
+	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes)
+	local n = #found_nodes or 0
 	if r > n then
 		minetest.log("warning","[mcl_mobs] No room for mob "..self.name.." at "..minetest.pos_to_string(vector.round(pos)))
 		return false

From d8d39ffd52a1c36315109f98cac53ee85a482b26 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Mon, 17 Jun 2024 20:27:55 -0500
Subject: [PATCH 02/13] Add spawnbox parameter that overrides collision box for
 spawn volume checks

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 1fb07247c..aed87631c 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -531,7 +531,7 @@ local function get_water_spawn(p)
 end
 
 local function has_room(self,pos)
-	local cb = self.collisionbox
+	local cb = self.spawnbox or self.collisionbox
 	local nodes = {}
 	if self.fly_in then
 		local t = type(self.fly_in)

From fa09b650108ed8d79e22f9e9ba4235aa3b0a2a5d Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Tue, 18 Jun 2024 06:07:30 -0500
Subject: [PATCH 03/13] Add most of the code for sub-node accurate spawning
 volume check (needs a function to calculate bounding box height of nodes)

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 44 +++++++++++++++++++++++------
 1 file changed, 36 insertions(+), 8 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index aed87631c..45516c754 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -548,19 +548,47 @@ local function has_room(self,pos)
 	p1.y = math.floor(p1.y)
 	p1.z = math.floor(p1.z)
 
-	local p2 = vector.offset(p1,cb[4] - cb[1], cb[5] - cb[2], cb[6] - cb[3])
+	local cb_height = cb[5] - cb[2]
+	local p2 = vector.offset(p1,cb[4] - cb[1], cb_height, cb[6] - cb[3])
 	p2.x = math.floor(p2.x)
 	p2.y = math.floor(p2.y)
 	p2.z = math.floor(p2.z)
 
-	local r = (p2.x - p1.x + 1) * (p2.y - p1.y + 1) * (p2.z - p1.z + 1)
-	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes)
-	local n = #found_nodes or 0
-	if r > n then
-		minetest.log("warning","[mcl_mobs] No room for mob "..self.name.." at "..minetest.pos_to_string(vector.round(pos)))
-		return false
+	-- Check if the entire spawn volume is free
+	local dx = p2.x - p1.x + 1
+	local dy = p2.y - p1.y + 1
+	local dz = p2.z - p1.z + 1
+	local n = #minetest.find_nodes_in_area(p1,p2,nodes) or 0
+	if n == ( dx * dz * dz ) then return true end
+
+	-- Make sure the entire volume except for the top level is free before checking the top layer
+	if dy > 1 then
+		n = #minetest.find_nodes_in_area(p1, vector.offset(p2, 0, -1, 0), nodes)
+		if n < (dx * dz * ( dy - 1)) then return false end
 	end
-	return true
+
+	-- Check the top layer to see if we have enough space to spawn in
+	local top_layer_height = 1
+	local processed = {}
+	for x = p1.x,p2.x do
+		for z = p1.z,p2.z do
+			local node = minetest.get_node(vector.new(x,p2.y,z)) or { name = "ignore" }
+			if not processed[node.name] then
+				local nodedef = minetest.registered_nodes
+
+				-- TODO: calculate node bounding box and select the lowest y value
+				local lowest_y = 0
+				top_layer_height = math.min(lowest_y, top_layer_height)
+
+				processed[node.name] = true
+			end
+		end
+	end
+	if top_layer_height + dy - 1 >= cb_height then return true end
+
+	-- We don't have room
+	mcl_log("No room for mob "..self.name.." at "..minetest.pos_to_string(vector.round(pos)))
+	return false
 end
 
 mcl_mobs.custom_biomecheck = nil

From 4d58f63485945709e8026e32a377f6bbe30fc265 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Mon, 24 Jun 2024 08:53:20 -0500
Subject: [PATCH 04/13] Implement partial node spawning check

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 45516c754..43a4e5dfa 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -572,15 +572,20 @@ local function has_room(self,pos)
 	local processed = {}
 	for x = p1.x,p2.x do
 		for z = p1.z,p2.z do
-			local node = minetest.get_node(vector.new(x,p2.y,z)) or { name = "ignore" }
-			if not processed[node.name] then
-				local nodedef = minetest.registered_nodes
+			local test_pos = vector.new(x,p2.y,z)
+			local node = minetest.get_node(test_pos) or { name = "ignore" }
+			local cache_name = string.format("%s-%d", node.name, node.param2)
+			if not processed[cache_name] then
+				-- Calculate node bounding box and select the lowest y value
+				local boxes = minetest.get_node_boxes("collision_box", test_pos, node)
+				for i = 1,#boxes do
+					local box = boxes[i]
+					local y_test = box[2] + 0.5
+					if y_test < top_layer_height then top_layer_height = y_test end
 
-				-- TODO: calculate node bounding box and select the lowest y value
-				local lowest_y = 0
-				top_layer_height = math.min(lowest_y, top_layer_height)
-
-				processed[node.name] = true
+					local y_test = box[5] + 0.5
+					if y_test < top_layer_height then top_layer_height = y_test end
+				end
 			end
 		end
 	end

From c41ce8ba59d4770199a771788abdeae181ab138b Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Mon, 24 Jun 2024 09:36:22 -0500
Subject: [PATCH 05/13] Make spiders require 3x1x3 space to spawn

---
 mods/ENTITIES/mobs_mc/spider.lua | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mods/ENTITIES/mobs_mc/spider.lua b/mods/ENTITIES/mobs_mc/spider.lua
index d01c7afbe..7fd8909ba 100644
--- a/mods/ENTITIES/mobs_mc/spider.lua
+++ b/mods/ENTITIES/mobs_mc/spider.lua
@@ -67,6 +67,7 @@ local spider = {
 	curiosity = 10,
 	head_yaw="z",
 	collisionbox = {-0.7, -0.01, -0.7, 0.7, 0.89, 0.7},
+	spawnbox = {-1.2, -0.01, -1.2, 1.2, 0.89, 1.2},
 	visual = "mesh",
 	mesh = "mobs_mc_spider.b3d",
 	textures = {

From fa3df0d8c6920bdf411f9aed07afd28a557ef7bf Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Wed, 26 Jun 2024 15:56:21 -0500
Subject: [PATCH 06/13] Add check for presence of minetest.get_node_boxes
 before attempting sub-node space checks

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 43a4e5dfa..987918e99 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -561,6 +561,9 @@ local function has_room(self,pos)
 	local n = #minetest.find_nodes_in_area(p1,p2,nodes) or 0
 	if n == ( dx * dz * dz ) then return true end
 
+	-- If we don't have an implementation of get_node_boxes, we can't check for sub-node space
+	if not minetest.get_node_boxes then return false end
+
 	-- Make sure the entire volume except for the top level is free before checking the top layer
 	if dy > 1 then
 		n = #minetest.find_nodes_in_area(p1, vector.offset(p2, 0, -1, 0), nodes)

From 15efd00a29b415221e4da17f91ab858648004829 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Wed, 26 Jun 2024 19:18:53 -0500
Subject: [PATCH 07/13] Replace second call to minetest.find_nodes_in_area with
 checking top layer for matching nodes, change p2 calculation to use
 ceil(value) - 1, fix dx*dy*dz calculation

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 987918e99..515b96e66 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -550,23 +550,31 @@ local function has_room(self,pos)
 
 	local cb_height = cb[5] - cb[2]
 	local p2 = vector.offset(p1,cb[4] - cb[1], cb_height, cb[6] - cb[3])
-	p2.x = math.floor(p2.x)
-	p2.y = math.floor(p2.y)
-	p2.z = math.floor(p2.z)
+	p2.x = math.ceil(p2.x) - 1
+	p2.y = math.ceil(p2.y) - 1
+	p2.z = math.ceil(p2.z) - 1
 
 	-- Check if the entire spawn volume is free
 	local dx = p2.x - p1.x + 1
 	local dy = p2.y - p1.y + 1
 	local dz = p2.z - p1.z + 1
-	local n = #minetest.find_nodes_in_area(p1,p2,nodes) or 0
-	if n == ( dx * dz * dz ) then return true end
+	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes) or 0
+	local n = #found_nodes
+	if n == ( dx * dy * dz ) then return true end
 
 	-- If we don't have an implementation of get_node_boxes, we can't check for sub-node space
 	if not minetest.get_node_boxes then return false end
 
 	-- Make sure the entire volume except for the top level is free before checking the top layer
 	if dy > 1 then
-		n = #minetest.find_nodes_in_area(p1, vector.offset(p2, 0, -1, 0), nodes)
+		-- Remove nodes in the top layer from the count
+		for i = 1,#found_nodes do
+			if found_nodes[i].y == p2.y then
+				n = n - 1
+			end
+		end
+
+		-- If the entire volume except the top layer isn't air (or nodes) then we can't spawn this mob here
 		if n < (dx * dz * ( dy - 1)) then return false end
 	end
 

From 8ef08128b16a92013fef80810a72f437e411fc70 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Wed, 26 Jun 2024 19:24:55 -0500
Subject: [PATCH 08/13] Add short circuit if sub-node space check isn't
 possible:

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 515b96e66..86c942be0 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -565,6 +565,10 @@ local function has_room(self,pos)
 	-- If we don't have an implementation of get_node_boxes, we can't check for sub-node space
 	if not minetest.get_node_boxes then return false end
 
+	-- Check if it's possible for a sub-node space check to succeed
+	local needed_in_bottom_section = (dx * dz * ( dy - 1))
+	if n < needed_in_bottom_section then return false end
+
 	-- Make sure the entire volume except for the top level is free before checking the top layer
 	if dy > 1 then
 		-- Remove nodes in the top layer from the count
@@ -575,7 +579,7 @@ local function has_room(self,pos)
 		end
 
 		-- If the entire volume except the top layer isn't air (or nodes) then we can't spawn this mob here
-		if n < (dx * dz * ( dy - 1)) then return false end
+		if n < needed_in_bottom_section then return false end
 	end
 
 	-- Check the top layer to see if we have enough space to spawn in

From 6c50e0a82b97c118eedcc370df2bd2ade8ae50fa Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Fri, 13 Sep 2024 17:10:05 -0500
Subject: [PATCH 09/13] Fix volume used for room check during spawn, make
 mcl_mobs.spawn check for room before adding entity, change iron golems and
 mob spawners to use mcl_mobs.spawn

---
 mods/CORE/mcl_util/init.lua         | 12 ++++++++
 mods/ENTITIES/mcl_mobs/spawning.lua | 40 +++++++++++++++++++--------
 mods/ENTITIES/mobs_mc/villager.lua  | 18 +++++++-----
 mods/ITEMS/mcl_mobspawners/init.lua | 43 ++++++++++-------------------
 4 files changed, 66 insertions(+), 47 deletions(-)

diff --git a/mods/CORE/mcl_util/init.lua b/mods/CORE/mcl_util/init.lua
index 1f53feef7..36cbf2e63 100644
--- a/mods/CORE/mcl_util/init.lua
+++ b/mods/CORE/mcl_util/init.lua
@@ -48,6 +48,18 @@ function table.pairs_by_keys(t, f)
 	return iter
 end
 
+local function table.pull_random_items(table)
+	local count = #table
+	return function()
+		local idx = math.random(count)
+		local res = table[idx]
+		table[idx] = table[count]
+		table[count] = nil
+		count = count - 1
+		return res
+	end
+end
+
 local LOGGING_ON = minetest.settings:get_bool("mcl_logging_default", false)
 local LOG_MODULE = "[MCL2]"
 function mcl_util.mcl_log(message, module, bypass_default_logger)
diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 86c942be0..8a2e099cf 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -530,7 +530,7 @@ local function get_water_spawn(p)
 		end
 end
 
-local function has_room(self,pos)
+local function has_room(self, pos)
 	local cb = self.spawnbox or self.collisionbox
 	local nodes = {}
 	if self.fly_in then
@@ -543,16 +543,16 @@ local function has_room(self,pos)
 	end
 	table.insert(nodes,"air")
 
-	local p1 = vector.offset(pos,cb[1],cb[2] + 1,cb[3])
-	p1.x = math.floor(p1.x)
-	p1.y = math.floor(p1.y)
-	p1.z = math.floor(p1.z)
-
+	-- Calculate area to check for room
 	local cb_height = cb[5] - cb[2]
-	local p2 = vector.offset(p1,cb[4] - cb[1], cb_height, cb[6] - cb[3])
-	p2.x = math.ceil(p2.x) - 1
-	p2.y = math.ceil(p2.y) - 1
-	p2.z = math.ceil(p2.z) - 1
+	local p1 = vector.new(
+		math.round(pos.x + cb[1]),
+		pos.y,
+		math.round(pos.z + cb[3]))
+	local p2 = vector.new(
+		math.round(pos.x + cb[4]),
+		math.ceil(p1.y + cb_height) - 1,
+		math.round(pos.z + cb[6]))
 
 	-- Check if the entire spawn volume is free
 	local dx = p2.x - p1.x + 1
@@ -560,7 +560,23 @@ local function has_room(self,pos)
 	local dz = p2.z - p1.z + 1
 	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes) or 0
 	local n = #found_nodes
-	if n == ( dx * dy * dz ) then return true end
+	--[[
+	minetest.log(dump({
+		cb = cb,
+		pos = pos,
+		n = n,
+		dx = dx,
+		dy = dy,
+		dz = dz,
+		p1 = p1,
+		p2 = p2,
+		found_nodes = found_nodes,
+		nodes = nodes,
+	}))
+	]]
+	if n == ( dx * dy * dz ) then
+		return true
+	end
 
 	-- If we don't have an implementation of get_node_boxes, we can't check for sub-node space
 	if not minetest.get_node_boxes then return false end
@@ -699,10 +715,10 @@ function mcl_mobs.spawn(pos,id)
 	if not pos or not id then return false end
 	local def = minetest.registered_entities[id] or minetest.registered_entities["mobs_mc:"..id] or minetest.registered_entities["extra_mobs:"..id]
 	if not def or not def.is_mob or (def.can_spawn and not def.can_spawn(pos)) then return false end
+	if not has_room(def, pos) then return false end
 	return minetest.add_entity(pos, def.name)
 end
 
-
 local function spawn_group(p,mob,spawn_on,amount_to_spawn)
 	local nn= minetest.find_nodes_in_area_under_air(vector.offset(p,-5,-3,-5),vector.offset(p,5,3,5),spawn_on)
 	local o
diff --git a/mods/ENTITIES/mobs_mc/villager.lua b/mods/ENTITIES/mobs_mc/villager.lua
index 47b4cb470..76cf2715d 100644
--- a/mods/ENTITIES/mobs_mc/villager.lua
+++ b/mods/ENTITIES/mobs_mc/villager.lua
@@ -1049,14 +1049,18 @@ local function has_summon_participants(self)
 end
 
 local function summon_golem(self)
-	vector.offset(self.object:get_pos(),-10,-10,-10)
-	local nn = minetest.find_nodes_in_area_under_air(vector.offset(self.object:get_pos(),-10,-10,-10),vector.offset(self.object:get_pos(),10,10,10),{"group:solid","group:water"})
-	table.shuffle(nn)
-	for _,n in pairs(nn) do
-		local up = minetest.find_nodes_in_area(vector.offset(n,0,1,0),vector.offset(n,0,3,0),{"air"})
-		if up and #up >= 3 then
+	local pos = self.object:get_pos()
+	local p1 = vector.offset(pos, -10, -10, -10)
+	local p2 = vector.offset(pos,  10,  10,  10)
+	local nn = minetest.find_nodes_in_area_under_air(p1, p2,{"group:solid","group:water"})
+	for n in table.pull_random_items(nn) do
+		n.y = n.y + 1
+		minetest.log("trying to summon golem at "..vector.to_string(n))
+
+		local summon = mcl_mobs.spawn(n, "mobs_mc:iron_golem")
+		if summon then
 			minetest.sound_play("mcl_portals_open_end_portal", {pos=n, gain=0.5, max_hear_distance = 16}, true)
-			return minetest.add_entity(vector.offset(n,0,1,0),"mobs_mc:iron_golem")
+			return summon
 		end
 	end
 end
diff --git a/mods/ITEMS/mcl_mobspawners/init.lua b/mods/ITEMS/mcl_mobspawners/init.lua
index f2ee44ab1..13fc1010e 100644
--- a/mods/ITEMS/mcl_mobspawners/init.lua
+++ b/mods/ITEMS/mcl_mobspawners/init.lua
@@ -147,20 +147,14 @@ local function spawn_mobs(pos, elapsed)
 	-- get meta
 	local meta = minetest.get_meta(pos)
 
-	-- get settings
-	local mob = meta:get_string("Mob")
-	local mlig = meta:get_int("MinLight")
-	local xlig = meta:get_int("MaxLight")
-	local num = meta:get_int("MaxMobsInArea")
-	local pla = meta:get_int("PlayerDistance")
-	local yof = meta:get_int("YOffset")
-
 	-- if amount is 0 then do nothing
+	local num = meta:get_int("MaxMobsInArea")
 	if num == 0 then
 		return
 	end
 
 	-- are we spawning a registered mob?
+	local mob = meta:get_string("Mob")
 	if not mcl_mobs.spawning_mobs[mob] then
 		minetest.log("error", "[mcl_mobspawners] Mob Spawner: Mob doesn't exist: "..mob)
 		return
@@ -174,17 +168,14 @@ local function spawn_mobs(pos, elapsed)
 	local timer = minetest.get_node_timer(pos)
 
 	-- spawn mob if player detected and in range
+	local pla = meta:get_int("PlayerDistance")
 	if pla > 0 then
-
 		local in_range = 0
 		local objs = minetest.get_objects_inside_radius(pos, pla)
 
 		for _,oir in pairs(objs) do
-
 			if oir:is_player() then
-
 				in_range = 1
-
 				break
 			end
 		end
@@ -213,7 +204,6 @@ local function spawn_mobs(pos, elapsed)
 
 	-- count mob objects of same type in area
 	for k, obj in ipairs(objs) do
-
 		ent = obj:get_luaentity()
 
 		if ent and ent.name and ent.name == mob then
@@ -228,31 +218,28 @@ local function spawn_mobs(pos, elapsed)
 	end
 
 	-- find air blocks within 8×3×8 nodes of spawner
+	local yof = meta:get_int("YOffset")
 	local air = minetest.find_nodes_in_area(
 		{x = pos.x - 4, y = pos.y - 1 + yof, z = pos.z - 4},
 		{x = pos.x + 4, y = pos.y + 1 + yof, z = pos.z + 4},
 		{"air"})
 
-	-- spawn up to 4 mobs in random air blocks
+	-- spawn mobs in random air blocks. Default max of 4
 	if air then
-		local max = 4
-		if spawn_count_overrides[mob] then
-			max = spawn_count_overrides[mob]
-		end
-		for a=1, max do
-			if #air <= 0 then
-				-- We're out of space! Stop spawning
-				break
-			end
-			local air_index = math.random(#air)
-			local pos2 = air[air_index]
-			local lig = minetest.get_node_light(pos2) or 0
+		local num_to_spawn = spawn_count_overrides[mob] or 4
+		local mlig = meta:get_int("MinLight")
+		local xlig = meta:get_int("MaxLight")
 
-			pos2.y = pos2.y + 0.5
+		for pos2 = table.pull_random_items(air) do
+			local pos2 = air[air_index]
 
 			-- only if light levels are within range
+			local lig = minetest.get_node_light(pos2) or 0
 			if lig >= mlig and lig <= xlig then
-				minetest.add_entity(pos2, mob)
+				if mcl_mobs.spawn(pos2, mob) then
+					num_to_spawn = num_to_spawn - 1
+					if num_to_spawn == 0 then break end
+				end
 			end
 			table.remove(air, air_index)
 		end

From e65370b8455cc4a68df6369927aaf9e1260e631f Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Fri, 13 Sep 2024 17:36:19 -0500
Subject: [PATCH 10/13] Fixes

---
 mods/CORE/mcl_util/init.lua         | 2 +-
 mods/ENTITIES/mobs_mc/villager.lua  | 1 -
 mods/ITEMS/mcl_mobspawners/init.lua | 5 +----
 3 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/mods/CORE/mcl_util/init.lua b/mods/CORE/mcl_util/init.lua
index 36cbf2e63..15f935a41 100644
--- a/mods/CORE/mcl_util/init.lua
+++ b/mods/CORE/mcl_util/init.lua
@@ -48,7 +48,7 @@ function table.pairs_by_keys(t, f)
 	return iter
 end
 
-local function table.pull_random_items(table)
+function table.pull_random_items(table)
 	local count = #table
 	return function()
 		local idx = math.random(count)
diff --git a/mods/ENTITIES/mobs_mc/villager.lua b/mods/ENTITIES/mobs_mc/villager.lua
index 76cf2715d..e80518e48 100644
--- a/mods/ENTITIES/mobs_mc/villager.lua
+++ b/mods/ENTITIES/mobs_mc/villager.lua
@@ -1055,7 +1055,6 @@ local function summon_golem(self)
 	local nn = minetest.find_nodes_in_area_under_air(p1, p2,{"group:solid","group:water"})
 	for n in table.pull_random_items(nn) do
 		n.y = n.y + 1
-		minetest.log("trying to summon golem at "..vector.to_string(n))
 
 		local summon = mcl_mobs.spawn(n, "mobs_mc:iron_golem")
 		if summon then
diff --git a/mods/ITEMS/mcl_mobspawners/init.lua b/mods/ITEMS/mcl_mobspawners/init.lua
index 13fc1010e..80f57faa8 100644
--- a/mods/ITEMS/mcl_mobspawners/init.lua
+++ b/mods/ITEMS/mcl_mobspawners/init.lua
@@ -230,9 +230,7 @@ local function spawn_mobs(pos, elapsed)
 		local mlig = meta:get_int("MinLight")
 		local xlig = meta:get_int("MaxLight")
 
-		for pos2 = table.pull_random_items(air) do
-			local pos2 = air[air_index]
-
+		for pos2 in table.pull_random_items(air) do
 			-- only if light levels are within range
 			local lig = minetest.get_node_light(pos2) or 0
 			if lig >= mlig and lig <= xlig then
@@ -241,7 +239,6 @@ local function spawn_mobs(pos, elapsed)
 					if num_to_spawn == 0 then break end
 				end
 			end
-			table.remove(air, air_index)
 		end
 	end
 

From 31a3788ce157eb5f8ff6a4cb79db25cbad1dc94c Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Fri, 13 Sep 2024 20:24:34 -0500
Subject: [PATCH 11/13] Address review comments

---
 mods/CORE/mcl_util/init.lua         | 20 +++++++++++---------
 mods/ENTITIES/mcl_mobs/spawning.lua |  4 ++--
 mods/ENTITIES/mobs_mc/villager.lua  |  3 ++-
 mods/ITEMS/mcl_mobspawners/init.lua |  3 ++-
 4 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/mods/CORE/mcl_util/init.lua b/mods/CORE/mcl_util/init.lua
index 15f935a41..6143bfb41 100644
--- a/mods/CORE/mcl_util/init.lua
+++ b/mods/CORE/mcl_util/init.lua
@@ -48,16 +48,18 @@ function table.pairs_by_keys(t, f)
 	return iter
 end
 
-function table.pull_random_items(table)
+-- Removes one element randomly selected from the array section of the table and
+-- returns it, or nil if there are no elements in the array section of the table
+function table.remove_random_element(table)
 	local count = #table
-	return function()
-		local idx = math.random(count)
-		local res = table[idx]
-		table[idx] = table[count]
-		table[count] = nil
-		count = count - 1
-		return res
-	end
+	if count == 0 then return nil end
+
+	local idx = math.random(count)
+	local res = table[idx]
+	table[idx] = table[count]
+	table[count] = nil
+	count = count - 1
+	return res
 end
 
 local LOGGING_ON = minetest.settings:get_bool("mcl_logging_default", false)
diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 8a2e099cf..d5ebe8788 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -574,7 +574,7 @@ local function has_room(self, pos)
 		nodes = nodes,
 	}))
 	]]
-	if n == ( dx * dy * dz ) then
+	if n == dx * dy * dz then
 		return true
 	end
 
@@ -582,7 +582,7 @@ local function has_room(self, pos)
 	if not minetest.get_node_boxes then return false end
 
 	-- Check if it's possible for a sub-node space check to succeed
-	local needed_in_bottom_section = (dx * dz * ( dy - 1))
+	local needed_in_bottom_section = dx * ( dy - 1) * dz
 	if n < needed_in_bottom_section then return false end
 
 	-- Make sure the entire volume except for the top level is free before checking the top layer
diff --git a/mods/ENTITIES/mobs_mc/villager.lua b/mods/ENTITIES/mobs_mc/villager.lua
index e80518e48..5ea20c707 100644
--- a/mods/ENTITIES/mobs_mc/villager.lua
+++ b/mods/ENTITIES/mobs_mc/villager.lua
@@ -1053,7 +1053,8 @@ local function summon_golem(self)
 	local p1 = vector.offset(pos, -10, -10, -10)
 	local p2 = vector.offset(pos,  10,  10,  10)
 	local nn = minetest.find_nodes_in_area_under_air(p1, p2,{"group:solid","group:water"})
-	for n in table.pull_random_items(nn) do
+	while #nn > 0 do
+		local n = table.remove_random_element(nn)
 		n.y = n.y + 1
 
 		local summon = mcl_mobs.spawn(n, "mobs_mc:iron_golem")
diff --git a/mods/ITEMS/mcl_mobspawners/init.lua b/mods/ITEMS/mcl_mobspawners/init.lua
index 80f57faa8..5c934a819 100644
--- a/mods/ITEMS/mcl_mobspawners/init.lua
+++ b/mods/ITEMS/mcl_mobspawners/init.lua
@@ -230,7 +230,8 @@ local function spawn_mobs(pos, elapsed)
 		local mlig = meta:get_int("MinLight")
 		local xlig = meta:get_int("MaxLight")
 
-		for pos2 in table.pull_random_items(air) do
+		while #air > 0 do
+			local pos2 = table.remove_random_element(air)
 			-- only if light levels are within range
 			local lig = minetest.get_node_light(pos2) or 0
 			if lig >= mlig and lig <= xlig then

From 626bdd13d8538e13dd7093cc61460a8062b6b9ef Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Fri, 13 Sep 2024 21:31:04 -0500
Subject: [PATCH 12/13] Change several places where mobs are created to use
 mcl_mobs.spawn() instead of minetest.add_entity()

---
 mods/ENTITIES/mcl_mobs/breeding.lua        |  3 +-
 mods/ENTITIES/mcl_mobs/init.lua            | 25 +++++++++--------
 mods/ENTITIES/mcl_mobs/spawning.lua        | 32 +++++++++++-----------
 mods/ENTITIES/mobs_mc/slime+magma_cube.lua | 12 ++++----
 mods/ENTITIES/mobs_mc/villager_evoker.lua  | 14 ++++++----
 mods/ENVIRONMENT/lightning/init.lua        |  7 ++---
 6 files changed, 50 insertions(+), 43 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/breeding.lua b/mods/ENTITIES/mcl_mobs/breeding.lua
index 90e625db8..559195681 100644
--- a/mods/ENTITIES/mcl_mobs/breeding.lua
+++ b/mods/ENTITIES/mcl_mobs/breeding.lua
@@ -105,7 +105,7 @@ end
 
 -- Spawn a child
 function mcl_mobs.spawn_child(pos, mob_type)
-	local child = minetest.add_entity(pos, mob_type)
+	local child = mcl_mobs.spawn(pos, mob_type)
 	if not child then
 		return
 	end
@@ -285,6 +285,7 @@ function mob_class:check_breeding()
 					end
 
 					local child = mcl_mobs.spawn_child(pos, parent1.name)
+					if not child then return end
 
 					local ent_c = child:get_luaentity()
 
diff --git a/mods/ENTITIES/mcl_mobs/init.lua b/mods/ENTITIES/mcl_mobs/init.lua
index 81b5fdfe7..74e6edbec 100644
--- a/mods/ENTITIES/mcl_mobs/init.lua
+++ b/mods/ENTITIES/mcl_mobs/init.lua
@@ -528,7 +528,7 @@ end
 -- Note: This also introduces the “spawn_egg” group:
 -- * spawn_egg=1: Spawn egg (generic mob, no metadata)
 -- * spawn_egg=2: Spawn egg (captured/tamed mob, metadata)
-function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addegg, no_creative)
+function mcl_mobs.register_egg(mob_id, desc, background_color, overlay_color, addegg, no_creative)
 
 	local grp = {spawn_egg = 1}
 
@@ -539,7 +539,7 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 
 	local invimg = "(spawn_egg.png^[multiply:" .. background_color ..")^(spawn_egg_overlay.png^[multiply:" .. overlay_color .. ")"
 	if old_spawn_icons then
-		local mobname = mob:gsub("mobs_mc:","")
+		local mobname = mob_id:gsub("mobs_mc:","")
 		local fn = "mobs_mc_spawn_icon_"..mobname..".png"
 		if mcl_util.file_exists(minetest.get_modpath("mobs_mc").."/textures/"..fn) then
 			invimg = fn
@@ -551,7 +551,7 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 	end
 
 	-- register old stackable mob egg
-	minetest.register_craftitem(mob, {
+	minetest.register_craftitem(mob_id, {
 
 		description = desc,
 		inventory_image = invimg,
@@ -561,7 +561,6 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 		_doc_items_usagehelp = S("Just place it where you want the mob to appear. Animals will spawn tamed, unless you hold down the sneak key while placing. If you place this on a mob spawner, you change the mob it spawns."),
 
 		on_place = function(itemstack, placer, pointed_thing)
-
 			local pos = pointed_thing.above
 
 			-- am I clicking on something with existing on_rightclick function?
@@ -571,11 +570,12 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 				return def.on_rightclick(pointed_thing.under, under, placer, itemstack)
 			end
 
+			local mob_name = itemstack:get_name()
+
 			if pos and within_limits(pos, 0)  and not minetest.is_protected(pos, placer:get_player_name()) then
 				local name = placer:get_player_name()
 				local privs = minetest.get_player_privs(name)
 
-
 				if under.name == "mcl_mobspawners:spawner" then
 					if minetest.is_protected(pointed_thing.under, name) then
 						minetest.record_protection_violation(pointed_thing.under, name)
@@ -593,7 +593,6 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 					--minetest.log("max light: " .. mob_light_lvl[2])
 
 					-- Handle egg conversion
-					local mob_name = itemstack:get_name()
 					local convert_to = (minetest.registered_entities[mob_name] or {})._convert_to
 					if convert_to then mob_name = convert_to end
 
@@ -604,19 +603,24 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 					return itemstack
 				end
 
-				if not minetest.registered_entities[mob] then
+				if not minetest.registered_entities[mob_name] then
 					return itemstack
 				end
 
 				if minetest.settings:get_bool("only_peaceful_mobs", false)
-						and minetest.registered_entities[mob].type == "monster" then
+						and minetest.registered_entities[mob_name].type == "monster" then
 					minetest.chat_send_player(name, S("Only peaceful mobs allowed!"))
 					return itemstack
 				end
 
-				pos.y = pos.y - 0.5
+				pos.y = pos.y - 1
+				local mob = mcl_mobs.spawn(pos, mob_name)
+				if not object then
+					pos.y = pos.y + 1
+					mob = mcl_mobs.spawn(pos, mob_name)
+					if not mob then return end
+				end
 
-				local mob = minetest.add_entity(pos, mob)
 				local entityname = itemstack:get_name()
 				minetest.log("action", "Player " ..name.." spawned "..entityname.." at "..minetest.pos_to_string(pos))
 				local ent = mob:get_luaentity()
@@ -647,5 +651,4 @@ function mcl_mobs.register_egg(mob, desc, background_color, overlay_color, addeg
 			return itemstack
 		end,
 	})
-
 end
diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index d5ebe8788..332603392 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -1,4 +1,5 @@
 --lua locals
+local DEBUG = false
 local math, vector, minetest, mcl_mobs = math, vector, minetest, mcl_mobs
 local mob_class = mcl_mobs.mob_class
 
@@ -547,7 +548,7 @@ local function has_room(self, pos)
 	local cb_height = cb[5] - cb[2]
 	local p1 = vector.new(
 		math.round(pos.x + cb[1]),
-		pos.y,
+		math.floor(pos.y),
 		math.round(pos.z + cb[3]))
 	local p2 = vector.new(
 		math.round(pos.x + cb[4]),
@@ -560,20 +561,20 @@ local function has_room(self, pos)
 	local dz = p2.z - p1.z + 1
 	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes) or 0
 	local n = #found_nodes
-	--[[
-	minetest.log(dump({
-		cb = cb,
-		pos = pos,
-		n = n,
-		dx = dx,
-		dy = dy,
-		dz = dz,
-		p1 = p1,
-		p2 = p2,
-		found_nodes = found_nodes,
-		nodes = nodes,
-	}))
-	]]
+	if DEBUG then
+		minetest.log(dump({
+			cb = cb,
+			pos = pos,
+			n = n,
+			dx = dx,
+			dy = dy,
+			dz = dz,
+			p1 = p1,
+			p2 = p2,
+			found_nodes = found_nodes,
+			nodes = nodes,
+		}))
+	end
 	if n == dx * dy * dz then
 		return true
 	end
@@ -623,7 +624,6 @@ local function has_room(self, pos)
 	if top_layer_height + dy - 1 >= cb_height then return true end
 
 	-- We don't have room
-	mcl_log("No room for mob "..self.name.." at "..minetest.pos_to_string(vector.round(pos)))
 	return false
 end
 
diff --git a/mods/ENTITIES/mobs_mc/slime+magma_cube.lua b/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
index fa9d24d09..57eb5a859 100644
--- a/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
+++ b/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
@@ -53,12 +53,14 @@ local spawn_children_on_die = function(child_mob, spawn_distance, eject_speed)
 					eject_speed = eject_speed * 0.5
 				end
 			end
-			local mob = minetest.add_entity(newpos, child_mob)
-			if not mother_stuck then
-				mob:set_velocity(dir * eject_speed)
+			local mob = mcl_mobs.spawn(newpos, child_mob)
+			if mob then
+				if not mother_stuck then
+					mob:set_velocity(dir * eject_speed)
+				end
+				mob:set_yaw(angle - math.pi/2)
+				table.insert(children, mob)
 			end
-			mob:set_yaw(angle - math.pi/2)
-			table.insert(children, mob)
 			angle = angle + (math.pi*2) / spawn_count
 		end
 		-- If mother was murdered, children attack the killer after 1 second
diff --git a/mods/ENTITIES/mobs_mc/villager_evoker.lua b/mods/ENTITIES/mobs_mc/villager_evoker.lua
index 9d465c25d..2dc175341 100644
--- a/mods/ENTITIES/mobs_mc/villager_evoker.lua
+++ b/mods/ENTITIES/mobs_mc/villager_evoker.lua
@@ -55,14 +55,16 @@ mcl_mobs.register_mob("mobs_mc:evoker", {
 		basepos.y = basepos.y + 1
 		for i=1, r do
 			local spawnpos = vector.add(basepos, minetest.yaw_to_dir(pr:next(0,360)))
-			local vex = minetest.add_entity(spawnpos, "mobs_mc:vex")
-			local ent = vex:get_luaentity()
+			local vex = mcl_mobs.spawn(spawnpos, "mobs_mc:vex")
+			if vex then
+				local ent = vex:get_luaentity()
 
-			-- Mark vexes as summoned and start their life clock (they take damage it reaches 0)
-			ent._summoned = true
-			ent._lifetimer = pr:next(33, 108)
+				-- Mark vexes as summoned and start their life clock (they take damage it reaches 0)
+				ent._summoned = true
+				ent._lifetimer = pr:next(33, 108)
 
-			table.insert(spawned_vexes[self],ent)
+				table.insert(spawned_vexes[self],ent)
+			end
 		end
 	end,
 	passive = false,
diff --git a/mods/ENVIRONMENT/lightning/init.lua b/mods/ENVIRONMENT/lightning/init.lua
index 079c9cb38..d4756bd9f 100644
--- a/mods/ENVIRONMENT/lightning/init.lua
+++ b/mods/ENVIRONMENT/lightning/init.lua
@@ -19,7 +19,6 @@ local set_node = minetest.set_node
 local sound_play = minetest.sound_play
 local add_particlespawner = minetest.add_particlespawner
 local after = minetest.after
-local add_entity = minetest.add_entity
 local get_objects_inside_radius = minetest.get_objects_inside_radius
 local get_item_group = minetest.get_item_group
 
@@ -165,7 +164,7 @@ function lightning.strike_func(pos, pos2, objects)
 
 	-- Events caused by the lightning strike: Fire, damage, mob transformations, rare skeleton spawn
 
-	pos2.y = pos2.y + 1/2
+	pos2.y = pos2.y + 1
 	local skeleton_lightning = false
 	if rng:next(1,100) <= 3 then
 		skeleton_lightning = true
@@ -174,14 +173,14 @@ function lightning.strike_func(pos, pos2, objects)
 		if get_node(pos2).name == "air" then
 			-- Low chance for a lightning to spawn skeleton horse + skeletons
 			if skeleton_lightning then
-				add_entity(pos2, "mobs_mc:skeleton_horse")
+				mcl_mobs.spawn(pos2, "mobs_mc:skeleton_horse")
 
 				local angle, posadd
 				angle = math.random() * math.pi * 2
 				for i=1,3 do
 					posadd = { x=math.cos(angle),y=0,z=math.sin(angle) }
 					posadd = vector.normalize(posadd)
-					local mob = add_entity(vector.add(pos2, posadd), "mobs_mc:skeleton")
+					local mob = mcl_mobs.spawn(vector.add(pos2, posadd), "mobs_mc:skeleton")
 					if mob then
 						mob:set_yaw(angle-math.pi/2)
 					end

From 0b62c827aa965990595471391bc8431acf1d3ada Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Fri, 13 Sep 2024 21:31:26 -0500
Subject: [PATCH 13/13] Remove has_room debug data

---
 mods/ENTITIES/mcl_mobs/spawning.lua | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/spawning.lua b/mods/ENTITIES/mcl_mobs/spawning.lua
index 332603392..8436540bf 100644
--- a/mods/ENTITIES/mcl_mobs/spawning.lua
+++ b/mods/ENTITIES/mcl_mobs/spawning.lua
@@ -1,5 +1,4 @@
 --lua locals
-local DEBUG = false
 local math, vector, minetest, mcl_mobs = math, vector, minetest, mcl_mobs
 local mob_class = mcl_mobs.mob_class
 
@@ -561,20 +560,6 @@ local function has_room(self, pos)
 	local dz = p2.z - p1.z + 1
 	local found_nodes = minetest.find_nodes_in_area(p1,p2,nodes) or 0
 	local n = #found_nodes
-	if DEBUG then
-		minetest.log(dump({
-			cb = cb,
-			pos = pos,
-			n = n,
-			dx = dx,
-			dy = dy,
-			dz = dz,
-			p1 = p1,
-			p2 = p2,
-			found_nodes = found_nodes,
-			nodes = nodes,
-		}))
-	end
 	if n == dx * dy * dz then
 		return true
 	end