1-- Minetest: builtin/item_entity.lua 2 3function core.spawn_item(pos, item) 4 -- Take item in any format 5 local stack = ItemStack(item) 6 local obj = core.add_entity(pos, "__builtin:item") 7 -- Don't use obj if it couldn't be added to the map. 8 if obj then 9 obj:get_luaentity():set_item(stack:to_string()) 10 end 11 return obj 12end 13 14-- If item_entity_ttl is not set, enity will have default life time 15-- Setting it to -1 disables the feature 16 17local time_to_live = tonumber(core.settings:get("item_entity_ttl")) or 900 18local gravity = tonumber(core.settings:get("movement_gravity")) or 9.81 19 20 21core.register_entity(":__builtin:item", { 22 initial_properties = { 23 hp_max = 1, 24 physical = true, 25 collide_with_objects = false, 26 collisionbox = {-0.3, -0.3, -0.3, 0.3, 0.3, 0.3}, 27 visual = "wielditem", 28 visual_size = {x = 0.4, y = 0.4}, 29 textures = {""}, 30 is_visible = false, 31 }, 32 33 itemstring = "", 34 moving_state = true, 35 physical_state = true, 36 -- Item expiry 37 age = 0, 38 -- Pushing item out of solid nodes 39 force_out = nil, 40 force_out_start = nil, 41 42 set_item = function(self, item) 43 local stack = ItemStack(item or self.itemstring) 44 self.itemstring = stack:to_string() 45 if self.itemstring == "" then 46 -- item not yet known 47 return 48 end 49 50 -- Backwards compatibility: old clients use the texture 51 -- to get the type of the item 52 local itemname = stack:is_known() and stack:get_name() or "unknown" 53 54 local max_count = stack:get_stack_max() 55 local count = math.min(stack:get_count(), max_count) 56 local size = 0.2 + 0.1 * (count / max_count) ^ (1 / 3) 57 local def = core.registered_items[itemname] 58 local glow = def and def.light_source and 59 math.floor(def.light_source / 2 + 0.5) 60 61 self.object:set_properties({ 62 is_visible = true, 63 visual = "wielditem", 64 textures = {itemname}, 65 visual_size = {x = size, y = size}, 66 collisionbox = {-size, -size, -size, size, size, size}, 67 automatic_rotate = math.pi * 0.5 * 0.2 / size, 68 wield_item = self.itemstring, 69 glow = glow, 70 }) 71 72 end, 73 74 get_staticdata = function(self) 75 return core.serialize({ 76 itemstring = self.itemstring, 77 age = self.age, 78 dropped_by = self.dropped_by 79 }) 80 end, 81 82 on_activate = function(self, staticdata, dtime_s) 83 if string.sub(staticdata, 1, string.len("return")) == "return" then 84 local data = core.deserialize(staticdata) 85 if data and type(data) == "table" then 86 self.itemstring = data.itemstring 87 self.age = (data.age or 0) + dtime_s 88 self.dropped_by = data.dropped_by 89 end 90 else 91 self.itemstring = staticdata 92 end 93 self.object:set_armor_groups({immortal = 1}) 94 self.object:set_velocity({x = 0, y = 2, z = 0}) 95 self.object:set_acceleration({x = 0, y = -gravity, z = 0}) 96 self:set_item() 97 end, 98 99 try_merge_with = function(self, own_stack, object, entity) 100 if self.age == entity.age then 101 -- Can not merge with itself 102 return false 103 end 104 105 local stack = ItemStack(entity.itemstring) 106 local name = stack:get_name() 107 if own_stack:get_name() ~= name or 108 own_stack:get_meta() ~= stack:get_meta() or 109 own_stack:get_wear() ~= stack:get_wear() or 110 own_stack:get_free_space() == 0 then 111 -- Can not merge different or full stack 112 return false 113 end 114 115 local count = own_stack:get_count() 116 local total_count = stack:get_count() + count 117 local max_count = stack:get_stack_max() 118 119 if total_count > max_count then 120 return false 121 end 122 -- Merge the remote stack into this one 123 124 local pos = object:get_pos() 125 pos.y = pos.y + ((total_count - count) / max_count) * 0.15 126 self.object:move_to(pos) 127 128 self.age = 0 -- Handle as new entity 129 own_stack:set_count(total_count) 130 self:set_item(own_stack) 131 132 entity.itemstring = "" 133 object:remove() 134 return true 135 end, 136 137 enable_physics = function(self) 138 if not self.physical_state then 139 self.physical_state = true 140 self.object:set_properties({physical = true}) 141 self.object:set_velocity({x=0, y=0, z=0}) 142 self.object:set_acceleration({x=0, y=-gravity, z=0}) 143 end 144 end, 145 146 disable_physics = function(self) 147 if self.physical_state then 148 self.physical_state = false 149 self.object:set_properties({physical = false}) 150 self.object:set_velocity({x=0, y=0, z=0}) 151 self.object:set_acceleration({x=0, y=0, z=0}) 152 end 153 end, 154 155 on_step = function(self, dtime, moveresult) 156 self.age = self.age + dtime 157 if time_to_live > 0 and self.age > time_to_live then 158 self.itemstring = "" 159 self.object:remove() 160 return 161 end 162 163 local pos = self.object:get_pos() 164 local node = core.get_node_or_nil({ 165 x = pos.x, 166 y = pos.y + self.object:get_properties().collisionbox[2] - 0.05, 167 z = pos.z 168 }) 169 -- Delete in 'ignore' nodes 170 if node and node.name == "ignore" then 171 self.itemstring = "" 172 self.object:remove() 173 return 174 end 175 176 if self.force_out then 177 -- This code runs after the entity got a push from the is_stuck code. 178 -- It makes sure the entity is entirely outside the solid node 179 local c = self.object:get_properties().collisionbox 180 local s = self.force_out_start 181 local f = self.force_out 182 local ok = (f.x > 0 and pos.x + c[1] > s.x + 0.5) or 183 (f.y > 0 and pos.y + c[2] > s.y + 0.5) or 184 (f.z > 0 and pos.z + c[3] > s.z + 0.5) or 185 (f.x < 0 and pos.x + c[4] < s.x - 0.5) or 186 (f.z < 0 and pos.z + c[6] < s.z - 0.5) 187 if ok then 188 -- Item was successfully forced out 189 self.force_out = nil 190 self:enable_physics() 191 return 192 end 193 end 194 195 if not self.physical_state then 196 return -- Don't do anything 197 end 198 199 assert(moveresult, 200 "Collision info missing, this is caused by an out-of-date/buggy mod or game") 201 202 if not moveresult.collides then 203 -- future TODO: items should probably decelerate in air 204 return 205 end 206 207 -- Push item out when stuck inside solid node 208 local is_stuck = false 209 local snode = core.get_node_or_nil(pos) 210 if snode then 211 local sdef = core.registered_nodes[snode.name] or {} 212 is_stuck = (sdef.walkable == nil or sdef.walkable == true) 213 and (sdef.collision_box == nil or sdef.collision_box.type == "regular") 214 and (sdef.node_box == nil or sdef.node_box.type == "regular") 215 end 216 217 if is_stuck then 218 local shootdir 219 local order = { 220 {x=1, y=0, z=0}, {x=-1, y=0, z= 0}, 221 {x=0, y=0, z=1}, {x= 0, y=0, z=-1}, 222 } 223 224 -- Check which one of the 4 sides is free 225 for o = 1, #order do 226 local cnode = core.get_node(vector.add(pos, order[o])).name 227 local cdef = core.registered_nodes[cnode] or {} 228 if cnode ~= "ignore" and cdef.walkable == false then 229 shootdir = order[o] 230 break 231 end 232 end 233 -- If none of the 4 sides is free, check upwards 234 if not shootdir then 235 shootdir = {x=0, y=1, z=0} 236 local cnode = core.get_node(vector.add(pos, shootdir)).name 237 if cnode == "ignore" then 238 shootdir = nil -- Do not push into ignore 239 end 240 end 241 242 if shootdir then 243 -- Set new item moving speed accordingly 244 local newv = vector.multiply(shootdir, 3) 245 self:disable_physics() 246 self.object:set_velocity(newv) 247 248 self.force_out = newv 249 self.force_out_start = vector.round(pos) 250 return 251 end 252 end 253 254 node = nil -- ground node we're colliding with 255 if moveresult.touching_ground then 256 for _, info in ipairs(moveresult.collisions) do 257 if info.axis == "y" then 258 node = core.get_node(info.node_pos) 259 break 260 end 261 end 262 end 263 264 -- Slide on slippery nodes 265 local def = node and core.registered_nodes[node.name] 266 local keep_movement = false 267 268 if def then 269 local slippery = core.get_item_group(node.name, "slippery") 270 local vel = self.object:get_velocity() 271 if slippery ~= 0 and (math.abs(vel.x) > 0.1 or math.abs(vel.z) > 0.1) then 272 -- Horizontal deceleration 273 local factor = math.min(4 / (slippery + 4) * dtime, 1) 274 self.object:set_velocity({ 275 x = vel.x * (1 - factor), 276 y = 0, 277 z = vel.z * (1 - factor) 278 }) 279 keep_movement = true 280 end 281 end 282 283 if not keep_movement then 284 self.object:set_velocity({x=0, y=0, z=0}) 285 end 286 287 if self.moving_state == keep_movement then 288 -- Do not update anything until the moving state changes 289 return 290 end 291 self.moving_state = keep_movement 292 293 -- Only collect items if not moving 294 if self.moving_state then 295 return 296 end 297 -- Collect the items around to merge with 298 local own_stack = ItemStack(self.itemstring) 299 if own_stack:get_free_space() == 0 then 300 return 301 end 302 local objects = core.get_objects_inside_radius(pos, 1.0) 303 for k, obj in pairs(objects) do 304 local entity = obj:get_luaentity() 305 if entity and entity.name == "__builtin:item" then 306 if self:try_merge_with(own_stack, obj, entity) then 307 own_stack = ItemStack(self.itemstring) 308 if own_stack:get_free_space() == 0 then 309 return 310 end 311 end 312 end 313 end 314 end, 315 316 on_punch = function(self, hitter) 317 local inv = hitter:get_inventory() 318 if inv and self.itemstring ~= "" then 319 local left = inv:add_item("main", self.itemstring) 320 if left and not left:is_empty() then 321 self:set_item(left) 322 return 323 end 324 end 325 self.itemstring = "" 326 self.object:remove() 327 end, 328}) 329