From c6b662ce7ae58a37dea89a88ea1edac6243b62d1 Mon Sep 17 00:00:00 2001
From: kay27 <kay27@bk.ru>
Date: Tue, 22 Jun 2021 05:10:45 +0400
Subject: [PATCH] [mcl_mobs/api] Add mob flow code from Crafter

---
 mods/ENTITIES/mcl_mobs/api/api.lua            |  1 +
 .../mcl_mobs/api/mob_functions/ai.lua         | 31 ++++++--
 .../mcl_mobs/api/mob_functions/flow_lib.lua   | 78 +++++++++++++++++++
 3 files changed, 102 insertions(+), 8 deletions(-)
 create mode 100644 mods/ENTITIES/mcl_mobs/api/mob_functions/flow_lib.lua

diff --git a/mods/ENTITIES/mcl_mobs/api/api.lua b/mods/ENTITIES/mcl_mobs/api/api.lua
index d1840f671..639eb517d 100644
--- a/mods/ENTITIES/mcl_mobs/api/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api/api.lua
@@ -129,6 +129,7 @@ end
 local api_path = minetest.get_modpath(minetest.get_current_modname()).."/api/mob_functions/"
 
 --ignite all parts of the api
+dofile(api_path .. "flow_lib.lua")
 dofile(api_path .. "ai.lua")
 dofile(api_path .. "animation.lua")
 dofile(api_path .. "collision.lua")
diff --git a/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua b/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
index d16d24929..88ce3274b 100644
--- a/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
+++ b/mods/ENTITIES/mcl_mobs/api/mob_functions/ai.lua
@@ -9,6 +9,8 @@ local minetest_get_item_group               = minetest.get_item_group
 local minetest_get_node                     = minetest.get_node
 local minetest_line_of_sight                = minetest.line_of_sight
 local minetest_get_node_light               = minetest.get_node_light
+local minetest_registered_nodes	            = minetest.registered_nodes
+local flow                                  = mobs.get_flowing_dir
 
 local DOUBLE_PI = math.pi * 2
 local THIRTY_SECONDTH_PI = DOUBLE_PI * 0.03125
@@ -521,8 +523,8 @@ ______ _
 |  _| | | | | |
 | |   | | |_| |
 \_|   |_|\__, |
-		  __/ |
-		 |___/
+	  __/ |
+	 |___/
 ]]--
 
 -- state switching logic (stand, walk, run, attacks)
@@ -675,12 +677,12 @@ end
 --[[
    ___
   |_  |
-	| |_   _ _ __ ___  _ __
-	| | | | | '_ ` _ \| '_ \
+    | |_   _ _ __ ___  _ __
+    | | | | | '_ ` _ \| '_ \
 /\__/ / |_| | | | | | | |_) |
 \____/ \__,_|_| |_| |_| .__/
-					  | |
-					  |_|
+		      | |
+		      |_|
 ]]--
 
 
@@ -787,8 +789,8 @@ ___  ___      _         _                 _
 | |\/| |/ _` | | '_ \  | |    / _ \ / _` | |/ __|
 | |  | | (_| | | | | | | |___| (_) | (_| | | (__
 \_|  |_/\__,_|_|_| |_| \_____/\___/ \__, |_|\___|
-									 __/ |
-									|___/
+				     __/ |
+				    |___/
 ]]--
 
 --the main loop
@@ -1011,6 +1013,19 @@ function mobs.mob_step(self, dtime)
 		end
 	end
 
+	--mobs flow from Crafter
+	local pos = self.object:get_pos()
+	if pos then
+		local flow_dir = flow(pos)
+		if flow_dir then
+			flow_dir = vector.multiply(flow_dir,10)
+			local vel = self.object:get_velocity()
+			local acceleration = vector.new(flow_dir.x-vel.x,flow_dir.y-vel.y,flow_dir.z-vel.z)
+			acceleration = vector.multiply(acceleration, 0.01)
+			self.object:add_velocity(acceleration)
+		end
+	end
+
 	--mob is stunned after being hit
 	if self.pause_timer > 0 then
 		self.pause_timer = self.pause_timer - dtime
diff --git a/mods/ENTITIES/mcl_mobs/api/mob_functions/flow_lib.lua b/mods/ENTITIES/mcl_mobs/api/mob_functions/flow_lib.lua
new file mode 100644
index 000000000..aa64bfb4e
--- /dev/null
+++ b/mods/ENTITIES/mcl_mobs/api/mob_functions/flow_lib.lua
@@ -0,0 +1,78 @@
+--this is from https://github.com/HybridDog/builtin_item/blob/e6dfd9dce86503b3cbd1474257eca5f6f6ca71c2/init.lua#L50
+local
+minetest,vector,math,pairs,minetest_get_node,vector_subtract,minetest_registered_nodes
+=
+minetest,vector,math,pairs,minetest.get_node,vector.subtract,minetest.registered_nodes
+
+local tab
+local n
+local function get_nodes(pos)
+	tab,n = {},1
+	for i = -1,1,2 do
+		for _,p in pairs({
+			{x=pos.x+i, y=pos.y, z=pos.z},
+			{x=pos.x, y=pos.y, z=pos.z+i}
+		}) do
+			tab[n] = {p, minetest_get_node(p)}
+			n = n+1
+		end
+	end
+	return tab
+end
+
+
+local data
+local param2
+local nd
+local par2
+local name
+local tmp
+local c_node
+function mobs.get_flowing_dir(pos)
+	c_node = minetest_get_node(pos).name
+	if c_node ~= "mcl_core:water_flowing" and c_node ~= "mcl_core:water" then
+		return nil
+	end
+	data = get_nodes(pos)
+	param2 = minetest_get_node(pos).param2
+	if param2 > 7 then
+		return nil
+	end
+	if c_node == "mcl_core:water" then
+		for _,i in pairs(data) do
+			nd = i[2]
+			name = nd.name
+			par2 = nd.param2
+			if name == "mcl_core:water_flowing" and par2 == 7 then
+				return(vector_subtract(i[1],pos))
+			end
+		end
+	end
+	for _,i in pairs(data) do
+		nd = i[2]
+		name = nd.name
+		par2 = nd.param2
+		if name == "mcl_core:water_flowing" and par2 < param2 then
+			return(vector_subtract(i[1],pos))
+		end
+	end
+	for _,i in pairs(data) do
+		nd = i[2]
+		name = nd.name
+		par2 = nd.param2
+		if name == "mcl_core:water_flowing" and par2 >= 11 then
+			return(vector_subtract(i[1],pos))
+		end
+	end
+	for _,i in pairs(data) do
+		nd = i[2]
+		name = nd.name
+		par2 = nd.param2
+		tmp = minetest_registered_nodes[name]
+		if tmp and not tmp.walkable and name ~= "mcl_core:water_flowing" and name ~= "mcl_core:water" then
+			return(vector_subtract(i[1],pos))
+		end
+	end
+
+	return nil
+end