From c7c47c1ca76ef94f78e513414a842e949e607256 Mon Sep 17 00:00:00 2001
From: Elias Fleckenstein <eliasfleckenstein@web.de>
Date: Sat, 17 Apr 2021 13:49:40 +0200
Subject: [PATCH] Increase mob_view_range_factor performance

---
 mods/ENTITIES/mcl_mobs/api.lua  |  3 +-
 mods/ITEMS/mcl_armor/api.lua    | 56 +++++++++------------------------
 mods/ITEMS/mcl_armor/init.lua   |  3 +-
 mods/ITEMS/mcl_armor/player.lua |  9 +++++-
 4 files changed, 27 insertions(+), 44 deletions(-)

diff --git a/mods/ENTITIES/mcl_mobs/api.lua b/mods/ENTITIES/mcl_mobs/api.lua
index 87aff0d76..d5caee66f 100644
--- a/mods/ENTITIES/mcl_mobs/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api.lua
@@ -177,7 +177,8 @@ local function object_in_range(self, object)
 	local factor
 	-- Apply view range reduction for special player armor
 	if object:is_player() and mod_armor then
-		factor = mcl_armor.get_mob_view_range_factor(object, self.name)
+		local factors = mcl_armor.player_view_range_factors[object]
+		factor = factors and factors[self.name]
 	end
 	-- Distance check
 	local dist
diff --git a/mods/ITEMS/mcl_armor/api.lua b/mods/ITEMS/mcl_armor/api.lua
index a5d1ac0e5..9f9384c6d 100644
--- a/mods/ITEMS/mcl_armor/api.lua
+++ b/mods/ITEMS/mcl_armor/api.lua
@@ -160,48 +160,8 @@ function mcl_armor.register_protection_enchantment(def)
 	}
 end
 
-function mcl_armor.get_armor_points(obj)
-	local points = 0
-	local inv = mcl_util.get_inventory(obj)
-	if inv then
-		for i = 2, 5 do
-			local itemstack = inv:get_stack("armor", i)
-			if not itemstack:is_empty() then
-				points = points + minetest.get_item_group(itemstack:get_name(), "mcl_armor_points")
-			end
-		end
-	end
-	return points
-end
-
--- Returns a change factor for a mob's view_range for the given object
--- or nil, if there's no change. Certain armors (like mob heads) can
--- affect the view range of mobs.
-function mcl_armor.get_mob_view_range_factor(obj, mob)
-	local inv = mcl_util.get_inventory(obj)
-	local factor
-	if inv then
-		for i = 2, 5 do
-			local itemstack = inv:get_stack("armor", i)
-			if not itemstack:is_empty() then
-				local def = itemstack:get_definition()
-				if def._mcl_armor_mob_range_mob == mob then
-					if not factor then
-						factor = def._mcl_armor_mob_range_factor
-					elseif factor == 0 then
-						return 0
-					else
-						factor = factor * def._mcl_armor_mob_range_factor
-					end
-				end
-			end
-		end
-	end
-	return factor
-end
-
 function mcl_armor.update(obj)
-	local info = {points = 0}
+	local info = {points = 0, view_range_factors = {}}
 
 	local inv = mcl_util.get_inventory(obj)
 
@@ -226,6 +186,20 @@ function mcl_armor.update(obj)
 				end
 
 				info.points = info.points + minetest.get_item_group(itemname, "mcl_armor_points")
+
+				local mob_range_mob = def._mcl_armor_mob_range_mob
+
+				if mob_range_mob then
+					local factor = info.view_range_factors[mob_range_mob]
+
+					if factor then
+						if factor > 0 then
+							info.view_range_factors[mob_range_mob] = factor * def._mcl_armor_mob_range_factor
+						end
+					else
+						info.view_range_factors[mob_range_mob] = def._mcl_armor_mob_range_factor
+					end
+				end
 			end
 		end
 	end
diff --git a/mods/ITEMS/mcl_armor/init.lua b/mods/ITEMS/mcl_armor/init.lua
index cc8fb2d32..0f7725010 100644
--- a/mods/ITEMS/mcl_armor/init.lua
+++ b/mods/ITEMS/mcl_armor/init.lua
@@ -55,7 +55,8 @@ mcl_armor = {
 				}
 			end,
 		}
-	}
+	},
+	player_view_range_factors = {},
 }
 
 local modpath = minetest.get_modpath("mcl_armor")
diff --git a/mods/ITEMS/mcl_armor/player.lua b/mods/ITEMS/mcl_armor/player.lua
index 651f8f776..50828fcea 100644
--- a/mods/ITEMS/mcl_armor/player.lua
+++ b/mods/ITEMS/mcl_armor/player.lua
@@ -61,7 +61,10 @@ mcl_player.player_register_model("mcl_armor_character_female.b3d", {
 function mcl_armor.update_player(player, info)
 	mcl_player.player_set_armor(player, info.texture, info.preview)
 
-	player:get_meta():set_int("mcl_armor:armor_points", info.points)
+	local meta = player:get_meta()
+	meta:set_int("mcl_armor:armor_points", info.points)
+
+	mcl_armor.player_view_range_factors[player] = view_range_factors
 end
 
 local function is_armor_action(inventory_info)
@@ -149,6 +152,10 @@ minetest.register_on_joinplayer(function(player)
 	end)
 end)
 
+minetest.register_on_leaveplayer(function(player)
+	mcl_armor.player_view_range_factors[player] = nil
+end)
+
 mcl_damage.register_modifier(function(player, hp_change, _, reason)
 	return mcl_armor.damage_modifier(player, hp_change, reason)
 end)