builtin/game/item_entity.lua

   1 -- Minetest: builtin/item_entity.lua
   2
   3 function 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
  12 end
  13
  14 -- If item_entity_ttl is not set, enity will have default life time
  15 -- Setting it to -1 disables the feature
  16
  17 local time_to_live = tonumber(core.settings:get("item_entity_ttl"))
  18 if not time_to_live then
  19         time_to_live = 900
  20 end
  21
  22 core.register_entity(":__builtin:item", {
  23         initial_properties = {
  24                 hp_max = 1,
  25                 physical = true,
  26                 collide_with_objects = false,
  27                 collisionbox = {-0.3, -0.3, -0.3, 0.3, 0.3, 0.3},
  28                 visual = "wielditem",
  29                 visual_size = {x = 0.4, y = 0.4},
  30                 textures = {""},
  31                 spritediv = {x = 1, y = 1},
  32                 initial_sprite_basepos = {x = 0, y = 0},
  33                 is_visible = false,
  34         },
  35
  36         itemstring = '',
  37         physical_state = true,
  38         age = 0,
  39
  40         set_item = function(self, itemstring)
  41                 self.itemstring = itemstring
  42                 local stack = ItemStack(itemstring)
  43                 local count = stack:get_count()
  44                 local max_count = stack:get_stack_max()
  45                 if count > max_count then
  46                         count = max_count
  47                         self.itemstring = stack:get_name().." "..max_count
  48                 end
  49                 local s = 0.2 + 0.1 * (count / max_count)
  50                 local c = s
  51                 local itemtable = stack:to_table()
  52                 local itemname = nil
  53                 if itemtable then
  54                         itemname = stack:to_table().name
  55                 end
  56                 -- Backwards compatibility: old clients use the texture
  57                 -- to get the type of the item
  58                 local item_texture = nil
  59                 local item_type = ""
  60                 if core.registered_items[itemname] then
  61                         item_texture = core.registered_items[itemname].inventory_image
  62                         item_type = core.registered_items[itemname].type
  63                 end
  64                 local prop = {
  65                         is_visible = true,
  66                         visual = "wielditem",
  67                         textures = {itemname},
  68                         visual_size = {x = s, y = s},
  69                         collisionbox = {-c, -c, -c, c, c, c},
  70                         automatic_rotate = math.pi * 0.5,
  71                         wield_item = itemstring,
  72                 }
  73                 self.object:set_properties(prop)
  74         end,
  75
  76         get_staticdata = function(self)
  77                 return core.serialize({
  78                         itemstring = self.itemstring,
  79                         always_collect = self.always_collect,
  80                         age = self.age,
  81                         dropped_by = self.dropped_by
  82                 })
  83         end,
  84
  85         on_activate = function(self, staticdata, dtime_s)
  86                 if string.sub(staticdata, 1, string.len("return")) == "return" then
  87                         local data = core.deserialize(staticdata)
  88                         if data and type(data) == "table" then
  89                                 self.itemstring = data.itemstring
  90                                 self.always_collect = data.always_collect
  91                                 if data.age then
  92                                         self.age = data.age + dtime_s
  93                                 else
  94                                         self.age = dtime_s
  95                                 end
  96                                 self.dropped_by = data.dropped_by
  97                         end
  98                 else
  99                         self.itemstring = staticdata
 100                 end
 101                 self.object:set_armor_groups({immortal = 1})
 102                 self.object:setvelocity({x = 0, y = 2, z = 0})
 103                 self.object:setacceleration({x = 0, y = -10, z = 0})
 104                 self:set_item(self.itemstring)
 105         end,
 106
 107   -- moves items from this stack to an other stack
 108         try_merge_with = function(self, own_stack, object, obj)
 109           -- other item's stack
 110                 local stack = ItemStack(obj.itemstring)
 111                 -- only merge if items are the same
 112                 if own_stack:get_name() == stack:get_name() and
 113                                 own_stack:get_meta() == stack:get_meta() and
 114                                 own_stack:get_wear() == stack:get_wear() and
 115                                 stack:get_free_space() > 0 then
 116                         local overflow = false
 117                         local count = stack:get_count() + own_stack:get_count()
 118                         local max_count = stack:get_stack_max()
 119                         if count > max_count then
 120                                 overflow = true
 121                                 stack:set_count(max_count)
 122                                 count = count - max_count
 123                                 own_stack:set_count(count)
 124                         else
 125                                 self.itemstring = ''
 126                                 stack:set_count(count)
 127                         end
 128                         local pos = object:getpos()
 129                         pos.y = pos.y + (count - stack:get_count()) / max_count * 0.15
 130                         object:moveto(pos, false)
 131                         local s, c
 132                         if not overflow then
 133                                 obj.itemstring = stack:to_string()
 134                                 s = 0.2 + 0.1 * (count / max_count)
 135                                 c = s
 136                                 object:set_properties({
 137                                         visual_size = {x = s, y = s},
 138                                         collisionbox = {-c, -c, -c, c, c, c},
 139                                         wield_item = obj.itemstring
 140                                 })
 141                                 self.object:remove()
 142                                 -- merging succeeded
 143                                 return true
 144                         else
 145                                 s = 0.4
 146                                 c = 0.3
 147                                 obj.itemstring = stack:to_string()
 148                                 object:set_properties({
 149                                         visual_size = {x = s, y = s},
 150                                         collisionbox = {-c, -c, -c, c, c, c},
 151                                         wield_item = obj.itemstring
 152                                 })
 153                                 s = 0.2 + 0.1 * (count / max_count)
 154                                 c = s
 155                                 self.itemstring = own_stack:to_string()
 156                                 self.object:set_properties({
 157                                         visual_size = {x = s, y = s},
 158                                         collisionbox = {-c, -c, -c, c, c, c},
 159                                         wield_item = self.itemstring
 160                                 })
 161                         end
 162                 end
 163                 -- merging didn't succeed
 164                 return false
 165         end,
 166
 167         on_step = function(self, dtime)
 168                 self.age = self.age + dtime
 169                 if time_to_live > 0 and self.age > time_to_live then
 170                         self.itemstring = ''
 171                         self.object:remove()
 172                         return
 173                 end
 174                 local p = self.object:getpos()
 175                 p.y = p.y - 0.5
 176                 local node = core.get_node_or_nil(p)
 177                 local in_unloaded = (node == nil)
 178                 if in_unloaded then
 179                         -- Don't infinetly fall into unloaded map
 180                         self.object:setvelocity({x = 0, y = 0, z = 0})
 181                         self.object:setacceleration({x = 0, y = 0, z = 0})
 182                         self.physical_state = false
 183                         self.object:set_properties({physical = false})
 184                         return
 185                 end
 186                 local nn = node.name
 187                 -- If node is not registered or node is walkably solid and resting on nodebox
 188                 local v = self.object:getvelocity()
 189                 if not core.registered_nodes[nn] or core.registered_nodes[nn].walkable and v.y == 0 then
 190                         if self.physical_state then
 191                                 local own_stack = ItemStack(self.object:get_luaentity().itemstring)
 192                                 -- Merge with close entities of the same item
 193                                 for _, object in ipairs(core.get_objects_inside_radius(p, 0.8)) do
 194                                         local obj = object:get_luaentity()
 195                                         if obj and obj.name == "__builtin:item"
 196                                                         and obj.physical_state == false then
 197                                                 if self:try_merge_with(own_stack, object, obj) then
 198                                                         return
 199                                                 end
 200                                         end
 201                                 end
 202                                 self.object:setvelocity({x = 0, y = 0, z = 0})
 203                                 self.object:setacceleration({x = 0, y = 0, z = 0})
 204                                 self.physical_state = false
 205                                 self.object:set_properties({physical = false})
 206                         end
 207                 else
 208                         if not self.physical_state then
 209                                 self.object:setvelocity({x = 0, y = 0, z = 0})
 210                                 self.object:setacceleration({x = 0, y = -10, z = 0})
 211                                 self.physical_state = true
 212                                 self.object:set_properties({physical = true})
 213                         end
 214                 end
 215         end,
 216
 217         on_punch = function(self, hitter)
 218                 local inv = hitter:get_inventory()
 219                 if inv and self.itemstring ~= '' then
 220                         local left = inv:add_item("main", self.itemstring)
 221                         if left and not left:is_empty() then
 222                                 self.itemstring = left:to_string()
 223                                 return
 224                         end
 225                 end
 226                 self.itemstring = ''
 227                 self.object:remove()
 228         end,
 229 })