From 80fcffcd38c2e672ae819ba7da926c9a79bcac9a Mon Sep 17 00:00:00 2001
From: kay27 <kay27@bk.ru>
Date: Thu, 18 Jun 2020 23:16:00 +0000
Subject: [PATCH] Fix Enderman's teleport by getting less nodes to pass
 PseudoRandom:next

---
 mods/ENTITIES/mobs_mc/enderman.lua | 46 ++++++++++++++++--------------
 1 file changed, 25 insertions(+), 21 deletions(-)

diff --git a/mods/ENTITIES/mobs_mc/enderman.lua b/mods/ENTITIES/mobs_mc/enderman.lua
index a80e8ed663..9b4857e292 100644
--- a/mods/ENTITIES/mobs_mc/enderman.lua
+++ b/mods/ENTITIES/mobs_mc/enderman.lua
@@ -468,32 +468,36 @@ mobs:register_mob("mobs_mc:enderman", {
 		else
 			-- Attempt to randomly teleport enderman
 			local pos = self.object:get_pos()
-			-- Find all solid nodes below air in a 65×65×65 cuboid centered on the enderman
-			local nodes = minetest.find_nodes_in_area_under_air(vector.subtract(pos, 32), vector.add(pos, 32), {"group:solid", "group:cracky", "group:crumbly"})
-			local telepos
-			if nodes ~= nil then
-				if #nodes > 0 then
-					-- Up to 64 attempts to teleport
-					for n=1, math.min(64, #nodes) do
-						local r = pr:next(1, #nodes)
-						local nodepos = nodes[r]
-						local node_ok = true
-						-- Selected node needs to have 3 nodes of free space above
-						for u=1, 3 do
-							local node = minetest.get_node({x=nodepos.x, y=nodepos.y+u, z=nodepos.z})
-							if minetest.registered_nodes[node.name].walkable then
-								node_ok = false
+			-- Up to 8 top-level attempts to teleport
+			for n=1, 8 do
+				local node_ok = false
+				-- We need to add (or subtract) different random numbers to each vector component, so it couldn't be done with a nice single vector.add() or .subtract():
+				local randomCube = vector.new( pos.x + 8*(pr:next(0,16)-8), pos.y + 8*(pr:next(0,16)-8), pos.z + 8*(pr:next(0,16)-8) )
+				local nodes = minetest.find_nodes_in_area_under_air(vector.subtract(randomCube, 4), vector.add(randomCube, 4), {"group:solid", "group:cracky", "group:crumbly"})
+				if nodes ~= nil then
+					if #nodes > 0 then
+						-- Up to 8 low-level (in total up to 8*8 = 64) attempts to teleport
+						for n=1, math.min(8, #nodes) do
+							local r = pr:next(1, #nodes)
+							local nodepos = nodes[r]
+							node_ok = true
+							for u=1, 3 do
+								local node = minetest.get_node({x=nodepos.x, y=nodepos.y+u, z=nodepos.z})
+								if minetest.registered_nodes[node.name].walkable then
+									node_ok = false
+									break
+								end
+							end
+							if node_ok then
+								self.object:set_pos({x=nodepos.x, y=nodepos.y+1, z=nodepos.z})
 								break
 							end
 						end
-						if node_ok then
-							telepos = {x=nodepos.x, y=nodepos.y+1, z=nodepos.z}
-						end
-					end
-					if telepos then
-						self.object:set_pos(telepos)
 					end
 				end
+				if node_ok then
+					 break
+				end
 			end
 		end
 	end,