1 -- Minetest: builtin/item.lua
3 local builtin_shared = ...
9 core.register_entity(":__builtin:falling_node", {
10 initial_properties = {
12 visual_size = {x = 0.667, y = 0.667},
16 collide_with_objects = false,
17 collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
23 set_node = function(self, node, meta)
25 self.meta = meta or {}
26 self.object:set_properties({
28 textures = {node.name},
32 get_staticdata = function(self)
37 return core.serialize(ds)
40 on_activate = function(self, staticdata)
41 self.object:set_armor_groups({immortal = 1})
43 local ds = core.deserialize(staticdata)
44 if ds and ds.node then
45 self:set_node(ds.node, ds.meta)
48 elseif staticdata ~= "" then
49 self:set_node({name = staticdata})
53 on_step = function(self, dtime)
55 local acceleration = self.object:getacceleration()
56 if not vector.equals(acceleration, {x = 0, y = -10, z = 0}) then
57 self.object:setacceleration({x = 0, y = -10, z = 0})
59 -- Turn to actual node when colliding with ground, or continue to move
60 local pos = self.object:getpos()
61 -- Position of bottom center point
62 local bcp = {x = pos.x, y = pos.y - 0.7, z = pos.z}
63 -- 'bcn' is nil for unloaded nodes
64 local bcn = core.get_node_or_nil(bcp)
65 -- Delete on contact with ignore at world edges
66 if bcn and bcn.name == "ignore" then
70 local bcd = bcn and core.registered_nodes[bcn.name]
72 (not bcd or bcd.walkable or
73 (core.get_item_group(self.node.name, "float") ~= 0 and
74 bcd.liquidtype ~= "none")) then
75 if bcd and bcd.leveled and
76 bcn.name == self.node.name then
77 local addlevel = self.node.level
78 if not addlevel or addlevel <= 0 then
79 addlevel = bcd.leveled
81 if core.add_node_level(bcp, addlevel) == 0 then
85 elseif bcd and bcd.buildable_to and
86 (core.get_item_group(self.node.name, "float") == 0 or
87 bcd.liquidtype == "none") then
91 local np = {x = bcp.x, y = bcp.y + 1, z = bcp.z}
93 local n2 = core.get_node(np)
94 local nd = core.registered_nodes[n2.name]
95 -- If it's not air or liquid, remove node and replace it with
97 if n2.name ~= "air" and (not nd or nd.liquidtype == "none") then
99 if nd and nd.buildable_to == false then
101 local drops = core.get_node_drops(n2, "")
102 for _, dropped_item in pairs(drops) do
103 core.add_item(np, dropped_item)
107 for _, callback in pairs(core.registered_on_dignodes) do
111 -- Create node and remove entity
112 local def = core.registered_nodes[self.node.name]
114 core.add_node(np, self.node)
116 local meta = core.get_meta(np)
117 meta:from_table(self.meta)
119 if def.sounds and def.sounds.place and def.sounds.place.name then
120 core.sound_play(def.sounds.place, {pos = np})
124 core.check_for_falling(np)
127 local vel = self.object:getvelocity()
128 if vector.equals(vel, {x = 0, y = 0, z = 0}) then
129 local npos = self.object:getpos()
130 self.object:setpos(vector.round(npos))
135 local function spawn_falling_node(p, node, meta)
136 local obj = core.add_entity(p, "__builtin:falling_node")
138 obj:get_luaentity():set_node(node, meta)
142 function core.spawn_falling_node(pos)
143 local node = core.get_node(pos)
144 if node.name == "air" or node.name == "ignore" then
147 local obj = core.add_entity(pos, "__builtin:falling_node")
149 obj:get_luaentity():set_node(node)
150 core.remove_node(pos)
156 local function drop_attached_node(p)
157 local n = core.get_node(p)
158 local drops = core.get_node_drops(n, "")
159 local def = core.registered_items[n.name]
160 if def and def.preserve_metadata then
161 local oldmeta = core.get_meta(p):to_table().fields
162 -- Copy pos and node because the callback can modify them.
163 local pos_copy = {x=p.x, y=p.y, z=p.z}
164 local node_copy = {name=n.name, param1=n.param1, param2=n.param2}
165 local drop_stacks = {}
166 for k, v in pairs(drops) do
167 drop_stacks[k] = ItemStack(v)
170 def.preserve_metadata(pos_copy, node_copy, oldmeta, drops)
173 for _, item in pairs(drops) do
175 x = p.x + math.random()/2 - 0.25,
176 y = p.y + math.random()/2 - 0.25,
177 z = p.z + math.random()/2 - 0.25,
179 core.add_item(pos, item)
183 function builtin_shared.check_attached_node(p, n)
184 local def = core.registered_nodes[n.name]
185 local d = {x = 0, y = 0, z = 0}
186 if def.paramtype2 == "wallmounted" or
187 def.paramtype2 == "colorwallmounted" then
188 -- The fallback vector here is in case 'wallmounted to dir' is nil due
189 -- to voxelmanip placing a wallmounted node without resetting a
190 -- pre-existing param2 value that is out-of-range for wallmounted.
191 -- The fallback vector corresponds to param2 = 0.
192 d = core.wallmounted_to_dir(n.param2) or {x = 0, y = 1, z = 0}
196 local p2 = vector.add(p, d)
197 local nn = core.get_node(p2).name
198 local def2 = core.registered_nodes[nn]
199 if def2 and not def2.walkable then
206 -- Some common functions
209 function core.check_single_for_falling(p)
210 local n = core.get_node(p)
211 if core.get_item_group(n.name, "falling_node") ~= 0 then
212 local p_bottom = {x = p.x, y = p.y - 1, z = p.z}
213 -- Only spawn falling node if node below is loaded
214 local n_bottom = core.get_node_or_nil(p_bottom)
215 local d_bottom = n_bottom and core.registered_nodes[n_bottom.name]
218 (core.get_item_group(n.name, "float") == 0 or
219 d_bottom.liquidtype == "none") and
221 (n.name ~= n_bottom.name or (d_bottom.leveled and
222 core.get_node_level(p_bottom) <
223 core.get_node_max_level(p_bottom))) and
225 (not d_bottom.walkable or d_bottom.buildable_to) then
226 n.level = core.get_node_level(p)
227 local meta = core.get_meta(p)
230 metatable = meta:to_table()
233 spawn_falling_node(p, n, metatable)
238 if core.get_item_group(n.name, "attached_node") ~= 0 then
239 if not builtin_shared.check_attached_node(p, n) then
240 drop_attached_node(p)
248 -- This table is specifically ordered.
249 -- We don't walk diagonals, only our direct neighbors, and self.
250 -- Down first as likely case, but always before self. The same with sides.
251 -- Up must come last, so that things above self will also fall all at once.
252 local check_for_falling_neighbors = {
253 {x = -1, y = -1, z = 0},
254 {x = 1, y = -1, z = 0},
255 {x = 0, y = -1, z = -1},
256 {x = 0, y = -1, z = 1},
257 {x = 0, y = -1, z = 0},
258 {x = -1, y = 0, z = 0},
259 {x = 1, y = 0, z = 0},
260 {x = 0, y = 0, z = 1},
261 {x = 0, y = 0, z = -1},
262 {x = 0, y = 0, z = 0},
263 {x = 0, y = 1, z = 0},
266 function core.check_for_falling(p)
267 -- Round p to prevent falling entities to get stuck.
270 -- We make a stack, and manually maintain size for performance.
271 -- Stored in the stack, we will maintain tables with pos, and
272 -- last neighbor visited. This way, when we get back to each
273 -- node, we know which directions we have already walked, and
274 -- which direction is the next to walk.
277 -- The neighbor order we will visit from our table.
281 -- Push current pos onto the stack.
283 s[n] = {p = p, v = v}
284 -- Select next node from neighbor list.
285 p = vector.add(p, check_for_falling_neighbors[v])
286 -- Now we check out the node. If it is in need of an update,
287 -- it will let us know in the return value (true = updated).
288 if not core.check_single_for_falling(p) then
289 -- If we don't need to "recurse" (walk) to it then pop
290 -- our previous pos off the stack and continue from there,
291 -- with the v value we were at when we last were at that
299 -- If there's nothing left on the stack, and no
300 -- more sides to walk to, we're done and can exit
301 if n == 0 and v == 11 then
305 -- The next round walk the next neighbor in list.
308 -- If we did need to walk the neighbor, then
309 -- start walking it from the walk order start (1),
310 -- and not the order we just pushed up the stack.
320 local function on_placenode(p, node)
321 core.check_for_falling(p)
323 core.register_on_placenode(on_placenode)
325 local function on_dignode(p, node)
326 core.check_for_falling(p)
328 core.register_on_dignode(on_dignode)
330 local function on_punchnode(p, node)
331 core.check_for_falling(p)
333 core.register_on_punchnode(on_punchnode)