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.setting_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                 local item_texture = nil
  57                 local item_type = ""
  58                 if core.registered_items[itemname] then
  59                         item_texture = core.registered_items[itemname].inventory_image
  60                         item_type = core.registered_items[itemname].type
  61                 end
  62                 local prop = {
  63                         is_visible = true,
  64                         visual = "wielditem",
  65                         textures = {itemname},
  66                         visual_size = {x = s, y = s},
  67                         collisionbox = {-c, -c, -c, c, c, c},
  68                         automatic_rotate = math.pi * 0.5,
  69                 }
  70                 self.object:set_properties(prop)
  71         end,
  72
  73         get_staticdata = function(self)
  74                 return core.serialize({
  75                         itemstring = self.itemstring,
  76                         always_collect = self.always_collect,
  77                         age = self.age
  78                 })
  79         end,
  80
  81         on_activate = function(self, staticdata, dtime_s)
  82                 if string.sub(staticdata, 1, string.len("return")) == "return" then
  83                         local data = core.deserialize(staticdata)
  84                         if data and type(data) == "table" then
  85                                 self.itemstring = data.itemstring
  86                                 self.always_collect = data.always_collect
  87                                 if data.age then
  88                                         self.age = data.age + dtime_s
  89                                 else
  90                                         self.age = dtime_s
  91                                 end
  92                         end
  93                 else
  94                         self.itemstring = staticdata
  95                 end
  96                 self.object:set_armor_groups({immortal = 1})
  97                 self.object:setvelocity({x = 0, y = 2, z = 0})
  98                 self.object:setacceleration({x = 0, y = -10, z = 0})
  99                 self:set_item(self.itemstring)
 100         end,
 101
 102         try_merge_with = function(self, own_stack, object, obj)
 103                 local stack = ItemStack(obj.itemstring)
 104                 if own_stack:get_name() == stack:get_name() and stack:get_free_space() > 0 then
 105                         local overflow = false
 106                         local count = stack:get_count() + own_stack:get_count()
 107                         local max_count = stack:get_stack_max()
 108                         if count > max_count then
 109                                 overflow = true
 110                                 count = count - max_count
 111                         else
 112                                 self.itemstring = ''
 113                         end
 114                         local pos = object:getpos()
 115                         pos.y = pos.y + (count - stack:get_count()) / max_count * 0.15
 116                         object:moveto(pos, false)
 117                         local s, c
 118                         local max_count = stack:get_stack_max()
 119                         local name = stack:get_name()
 120                         if not overflow then
 121                                 obj.itemstring = name .. " " .. count
 122                                 s = 0.2 + 0.1 * (count / max_count)
 123                                 c = s
 124                                 object:set_properties({
 125                                         visual_size = {x = s, y = s},
 126                                         collisionbox = {-c, -c, -c, c, c, c}
 127                                 })
 128                                 self.object:remove()
 129                                 -- merging succeeded
 130                                 return true
 131                         else
 132                                 s = 0.4
 133                                 c = 0.3
 134                                 object:set_properties({
 135                                         visual_size = {x = s, y = s},
 136                                         collisionbox = {-c, -c, -c, c, c, c}
 137                                 })
 138                                 obj.itemstring = name .. " " .. max_count
 139                                 s = 0.2 + 0.1 * (count / max_count)
 140                                 c = s
 141                                 self.object:set_properties({
 142                                         visual_size = {x = s, y = s},
 143                                         collisionbox = {-c, -c, -c, c, c, c}
 144                                 })
 145                                 self.itemstring = name .. " " .. count
 146                         end
 147                 end
 148                 -- merging didn't succeed
 149                 return false
 150         end,
 151
 152         on_step = function(self, dtime)
 153                 self.age = self.age + dtime
 154                 if time_to_live > 0 and self.age > time_to_live then
 155                         self.itemstring = ''
 156                         self.object:remove()
 157                         return
 158                 end
 159                 local p = self.object:getpos()
 160                 p.y = p.y - 0.5
 161                 local node = core.get_node_or_nil(p)
 162                 local in_unloaded = (node == nil)
 163                 if in_unloaded then
 164                         -- Don't infinetly fall into unloaded map
 165                         self.object:setvelocity({x = 0, y = 0, z = 0})
 166                         self.object:setacceleration({x = 0, y = 0, z = 0})
 167                         self.physical_state = false
 168                         self.object:set_properties({physical = false})
 169                         return
 170                 end
 171                 local nn = node.name
 172                 -- If node is not registered or node is walkably solid and resting on nodebox
 173                 local v = self.object:getvelocity()
 174                 if not core.registered_nodes[nn] or core.registered_nodes[nn].walkable and v.y == 0 then
 175                         if self.physical_state then
 176                                 local own_stack = ItemStack(self.object:get_luaentity().itemstring)
 177                                 -- Merge with close entities of the same item
 178                                 for _, object in ipairs(core.get_objects_inside_radius(p, 0.8)) do
 179                                         local obj = object:get_luaentity()
 180                                         if obj and obj.name == "__builtin:item"
 181                                                         and obj.physical_state == false then
 182                                                 if self:try_merge_with(own_stack, object, obj) then
 183                                                         return
 184                                                 end
 185                                         end
 186                                 end
 187                                 self.object:setvelocity({x = 0, y = 0, z = 0})
 188                                 self.object:setacceleration({x = 0, y = 0, z = 0})
 189                                 self.physical_state = false
 190                                 self.object:set_properties({physical = false})
 191                         end
 192                 else
 193                         if not self.physical_state then
 194                                 self.object:setvelocity({x = 0, y = 0, z = 0})
 195                                 self.object:setacceleration({x = 0, y = -10, z = 0})
 196                                 self.physical_state = true
 197                                 self.object:set_properties({physical = true})
 198                         end
 199                 end
 200         end,
 201
 202         on_punch = function(self, hitter)
 203                 if self.itemstring ~= '' then
 204                         local left = hitter:get_inventory():add_item("main", self.itemstring)
 205                         if not left:is_empty() then
 206                                 self.itemstring = left:to_string()
 207                                 return
 208                         end
 209                 end
 210                 self.itemstring = ''
 211                 self.object:remove()
 212         end,
 213 })