mods/hades_trees/leafdecay.lua

   1 --
   2 -- Leafdecay
   3 --
   4
   5 -- To enable leaf decay for a node, add it to the "leafdecay" group.
   6 --
   7 -- The rating of the group determines how far from a node in the group "tree"
   8 -- the node can be without decaying.
   9 --
  10 -- If param2 of the node is ~= 0, the node will always be preserved. Thus, if
  11 -- the player places a node of that kind, you will want to set param2=1 or so.
  12 --
  13 -- If the node is in the leafdecay_drop group then the it will always be dropped
  14 -- as an item
  15
  16
  17 hades_trees.leafdecay_trunk_cache = {}
  18 hades_trees.leafdecay_enable_cache = true
  19 -- Spread the load of finding trunks
  20 hades_trees.leafdecay_trunk_find_allow_accumulator = 0
  21
  22 minetest.register_globalstep(function(dtime)
  23         local finds_per_second = 5000
  24         hades_trees.leafdecay_trunk_find_allow_accumulator =
  25                         math.floor(dtime * finds_per_second)
  26 end)
  27
  28 local function leafdecay_particles(pos, node)
  29         minetest.add_particlespawner({
  30                 amount = math.random(10, 20),
  31                 time = 0.1,
  32                 minpos = vector.add(pos, {x=-0.4, y=-0.4, z=-0.4}),
  33                 maxpos = vector.add(pos, {x=0.4, y=0.4, z=0.4}),
  34                 minvel = {x=-0.2, y=-0.2, z=-0.2},
  35                 maxvel = {x=0.2, y=0.1, z=0.2},
  36                 minacc = {x=0, y=-9.81, z=0},
  37                 maxacc = {x=0, y=-9.81, z=0},
  38                 minexptime = 0.1,
  39                 maxexptime = 0.5,
  40                 minsize = 0.5,
  41                 maxsize = 1.5,
  42                 collisiondetection = true,
  43                 vertical = false,
  44                 node = node,
  45         })
  46 end
  47
  48 minetest.register_abm({
  49         label = "Leaf decay",
  50         nodenames = {"group:leafdecay"},
  51         neighbors = {"air", "group:liquid"},
  52         -- A low interval and a high inverse chance spreads the load
  53         interval = 2,
  54         chance = 5,
  55
  56         action = function(p0, node, _, _)
  57                 minetest.log("verbose", "[hades_trees] leafdecay ABM at "..p0.x..", "..p0.y..", "..p0.z..")")
  58                 local do_preserve = false
  59                 local d = minetest.registered_nodes[node.name].groups.leafdecay
  60                 if not d or d == 0 then
  61                         minetest.log("verbose", "[hades_trees] not groups.leafdecay")
  62                         return
  63                 end
  64                 local n0 = minetest.get_node(p0)
  65                 if n0.param2 ~= 0 then
  66                         -- Prevent decay
  67                         return
  68                 end
  69                 local p0_hash = nil
  70                 if hades_trees.leafdecay_enable_cache then
  71                         p0_hash = minetest.hash_node_position(p0)
  72                         local trunkp = hades_trees.leafdecay_trunk_cache[p0_hash]
  73                         if trunkp then
  74                                 local n = minetest.get_node(trunkp)
  75                                 local reg = minetest.registered_nodes[n.name]
  76                                 -- Assume ignore is a trunk, to make the thing work at the border of the active area
  77                                 if n.name == "ignore" or (reg and reg.groups.tree and reg.groups.tree ~= 0) then
  78                                         minetest.log("verbose", "[hades_trees] leafdecay: cached trunk still exists")
  79                                         return
  80                                 end
  81                                 minetest.log("verbose", "[hades_trees] leafdecay: cached trunk is invalid")
  82                                 -- Cache is invalid
  83                                 table.remove(hades_trees.leafdecay_trunk_cache, p0_hash)
  84                         end
  85                 end
  86                 if hades_trees.leafdecay_trunk_find_allow_accumulator <= 0 then
  87                         return
  88                 end
  89                 hades_trees.leafdecay_trunk_find_allow_accumulator =
  90                                 hades_trees.leafdecay_trunk_find_allow_accumulator - 1
  91                 -- Assume ignore is a trunk, to make the thing work at the border of the active area
  92                 local p1 = minetest.find_node_near(p0, d, {"ignore", "group:tree"})
  93                 if p1 then
  94                         do_preserve = true
  95                         if hades_trees.leafdecay_enable_cache then
  96                                 minetest.log("verbose", "[hades_trees] leafdecay: caching trunk")
  97                                 -- Cache the trunk
  98                                 hades_trees.leafdecay_trunk_cache[p0_hash] = p1
  99                         end
 100                 end
 101                 if not do_preserve then
 102                         -- Drop stuff other than the node itself
 103                         local itemstacks = minetest.get_node_drops(n0.name)
 104                         local drop_items = false
 105                         for _, itemname in ipairs(itemstacks) do
 106                                 if minetest.get_item_group(n0.name, "leafdecay_drop") ~= 0 or
 107                                                 itemname ~= n0.name then
 108                                         local p_drop = {
 109                                                 x = p0.x - 0.5 + math.random(),
 110                                                 y = p0.y - 0.5 + math.random(),
 111                                                 z = p0.z - 0.5 + math.random(),
 112                                         }
 113                                         drop_items = true
 114                                         minetest.add_item(p_drop, itemname)
 115                                 end
 116                         end
 117                         -- Remove node
 118                         minetest.remove_node(p0)
 119                         if not drop_items then
 120                                 leafdecay_particles(p0, n0)
 121                         end
 122                         minetest.check_for_falling(p0)
 123                 end
 124         end
 125 })