nalc_game/mods/default/leafdecay.lua
2012-11-21 18:05:52 +01:00

93 lines
2.9 KiB
Lua

-- minetest/default/leafdecay.lua
-- To enable leaf decay for a node, add it to the "leafdecay" group.
--
-- The rating of the group determines how far from a node in the group "tree"
-- the node can be without decaying.
--
-- If param2 of the node is ~= 0, the node will always be preserved. Thus, if
-- the player places a node of that kind, you will want to set param2=1 or so.
default.leafdecay_trunk_cache = {}
default.leafdecay_enable_cache = true
-- Spread the load of finding trunks
default.leafdecay_trunk_find_allow_accumulator = 0
minetest.register_globalstep(function(dtime)
local finds_per_second = 5000
default.leafdecay_trunk_find_allow_accumulator =
math.floor(dtime * finds_per_second)
end)
minetest.register_abm({
nodenames = {"group:leafdecay"},
neighbors = {"air", "group:liquid"},
-- A low interval and a high inverse chance spreads the load
interval = 2,
chance = 5,
action = function(p0, node, _, _)
--print("leafdecay ABM at "..p0.x..", "..p0.y..", "..p0.z..")")
local do_preserve = false
local d = minetest.registered_nodes[node.name].groups.leafdecay
if not d or d == 0 then
--print("not groups.leafdecay")
return
end
local n0 = minetest.env:get_node(p0)
if n0.param2 ~= 0 then
--print("param2 ~= 0")
return
end
local p0_hash = nil
if default.leafdecay_enable_cache then
p0_hash = minetest.hash_node_position(p0)
local trunkp = default.leafdecay_trunk_cache[p0_hash]
if trunkp then
local n = minetest.env:get_node(trunkp)
local reg = minetest.registered_nodes[n.name]
-- Assume ignore is a trunk, to make the thing work at the border of the active area
if n.name == "ignore" or (reg and reg.groups.tree and reg.groups.tree ~= 0) then
--print("cached trunk still exists")
return
end
--print("cached trunk is invalid")
-- Cache is invalid
table.remove(default.leafdecay_trunk_cache, p0_hash)
end
end
if default.leafdecay_trunk_find_allow_accumulator <= 0 then
return
end
default.leafdecay_trunk_find_allow_accumulator =
default.leafdecay_trunk_find_allow_accumulator - 1
-- Assume ignore is a trunk, to make the thing work at the border of the active area
local p1 = minetest.env:find_node_near(p0, d, {"ignore", "group:tree"})
if p1 then
do_preserve = true
if default.leafdecay_enable_cache then
--print("caching trunk")
-- Cache the trunk
default.leafdecay_trunk_cache[p0_hash] = p1
end
end
if not do_preserve then
-- Drop stuff other than the node itself
itemstacks = minetest.get_node_drops(n0.name)
for _, itemname in ipairs(itemstacks) do
if itemname ~= n0.name then
local p_drop = {
x = p0.x - 0.5 + math.random(),
y = p0.y - 0.5 + math.random(),
z = p0.z - 0.5 + math.random(),
}
minetest.env:add_item(p_drop, itemname)
end
end
-- Remove node
minetest.env:remove_node(p0)
end
end
})