How much storing values in metadata affects performance?

[yzelast]

Hi guys, i'm implementing a feature in my mod that makes the leaves regrow after some time, and after some tests it looks like using metadatas is the easiest way to do it.
I only need to store 2 values, the node name and the facedir, and i wanna know if having a lot of these metadatas together will affect the game performance.

Here is the code i used to test:
- setting the values

Code: Select all

minetest.override_item("default:leaves", {
	description = "Apple Leaves",
	drop = {max_items = 1, 
		items = {
			{items = {"default:stick"}, rarity = 0},
			{items = {"default:sapling"}, rarity = 0},
		},
	},
	groups = {snappy = 3, leafdecay = 3, flammable = 2, leaves = 1, apple = 1},

	on_punch = function(pos)
	local node = minetest.get_node(pos)
		minetest.set_node(pos, {name="realtrees:invisible_leaves"})
	local meta = minetest.get_meta(pos)
		meta:set_int("face",node.param2)
		meta:set_string("name",node.name)
	end,

	on_timer = function(pos)
		realtrees.leafdecay(pos, 5, "apple", "default:leaves")
	end,
})

- getting the values

Code: Select all

minetest.register_node("realtrees:invisible_leaves", {
	description = "Invisible Apple Leaves",
	drawtype = "airlike",
	paramtype = "light",
	paramtype2 = "facedir",
	walkable = true,
	pointable = true,
	buildable_to = true,

	on_punch = function(pos)
		minetest.get_node_timer(pos):start(5)
	end,

	on_timer = function(pos)
	local meta = minetest.get_meta(pos)
	local face = meta:get_int("face")
	local name = meta:get_string("name")
		minetest.set_node(pos, {name=name, param2=face})
	end,
})

The way i was trying to implement this feature was using an invisible node for each different leaf, so i would have at least 20 different nodes just for this stuff...

[Krock]

Overall it'll be about equal.

Metadata will likely make the map a little bigger than if you'd use different nodes for each kind of leaves.
Individual nodes will make the client's initialization process to take a little bit longer.

If you use the same node many times in the mapblock (as in: one next to each other) then the client can combine the faces and thus, rendering might be a tiny bit faster.
Both variants perform about the same, performance isn't a concern in your case.