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