Merge pull request 'Improve underwater item physics' (#351) from Gustavo6046/MineClone5:item-physics into master

Reviewed-on: MineClone5/MineClone5#351

mods/ENTITIES/mcl_item_entity/init.lua

@@ -156,6 +156,10 @@ minetest.register_globalstep(function(dtime)
 								object:set_velocity({x=0,y=0,z=0})
 								object:set_acceleration({x=0,y=0,z=0})
 
+								if object._flowing then
+								    object._flowing = false
+								end
+
 								object:move_to(checkpos)
 
 								pool[name] = pool[name] + 1
@@ -795,6 +799,9 @@ minetest.register_entity(":__builtin:item", {
 
 				local oldvel = self.object:get_velocity() -- v is vector, vel is velocity
 
+				-- apply gravity *before* drag computations
+				oldvel.y = oldvel.y - get_gravity() * dtime
+
 				-- drag
 				local fluid_drag = item_drop_settings.fluid_drag
 
@@ -808,12 +815,6 @@ minetest.register_entity(":__builtin:item", {
                 newv.x = newv.x - (oldvel.x - newv.x) * fluid_drag * dtime
                 newv.y = newv.y - (oldvel.y - newv.y) * fluid_drag * dtime
                 newv.z = newv.z - (oldvel.z - newv.z) * fluid_drag * dtime
-
-                newv.y = newv.y + -0.22 -- (keep slight downward thrust from previous version of code)
-                                        -- NOTE:    is there any particular reason we have this, anyway?
-                                        --          since fluid drag is now on, we could as well just
-                                        --          apply gravity here; drag will slow down the fall
-                                        --          realistically
 				
 				self.object:set_velocity({x = oldvel.x + newv.x * dtime, y = oldvel.y + newv.y * dtime, z = oldvel.z + newv.z * dtime})