From fb8c5300cda575dae921a59d2be23fc4cd6cf50f Mon Sep 17 00:00:00 2001
From: Wuzzy <Wuzzy2@mail.ru>
Date: Tue, 8 May 2018 00:02:07 +0200
Subject: [PATCH] Slow down arrows in liquids

This is a rought first implementation, very basic.
---
 mods/ITEMS/mcl_bows/arrow.lua | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/mods/ITEMS/mcl_bows/arrow.lua b/mods/ITEMS/mcl_bows/arrow.lua
index 8273fb721..0eda86895 100644
--- a/mods/ITEMS/mcl_bows/arrow.lua
+++ b/mods/ITEMS/mcl_bows/arrow.lua
@@ -135,6 +135,21 @@ THROWING_ARROW_ENTITY.on_step = function(self, dtime)
 				minetest.add_item(self._lastpos, 'mcl_bows:arrow')
 			end
 			self.object:remove()
+		elseif (def and def.liquidtype ~= "none") then
+			-- Slow down arrow in liquids
+			local v = def.liquid_viscosity
+			if not v then
+				v = 0
+			end
+			local vpenalty = math.max(0.1, 0.98 - 0.1 * v)
+			local vel = self.object:get_velocity()
+			if math.abs(vel.x) > 0.001 then
+				vel.x = vel.x * vpenalty
+			end
+			if math.abs(vel.z) > 0.001 then
+				vel.z = vel.z * vpenalty
+			end
+			self.object:set_velocity(vel)
 		end
 	end