builtin/game/falling.lua

   1 -- Minetest: builtin/item.lua
   2
   3 --
   4 -- Falling stuff
   5 --
   6
   7 core.register_entity(":__builtin:falling_node", {
   8         initial_properties = {
   9                 visual = "wielditem",
  10                 visual_size = {x = 0.667, y = 0.667},
  11                 textures = {},
  12                 physical = true,
  13                 is_visible = false,
  14                 collide_with_objects = false,
  15                 collisionbox = {-0.5, -0.5, -0.5, 0.5, 0.5, 0.5},
  16         },
  17
  18         node = {},
  19
  20         set_node = function(self, node)
  21                 self.node = node
  22                 self.object:set_properties({
  23                         is_visible = true,
  24                         textures = {node.name},
  25                 })
  26         end,
  27
  28         get_staticdata = function(self)
  29                 return core.serialize(self.node)
  30         end,
  31
  32         on_activate = function(self, staticdata)
  33                 self.object:set_armor_groups({immortal = 1})
  34
  35                 local node = core.deserialize(staticdata)
  36                 if node then
  37                         self:set_node(node)
  38                 elseif staticdata ~= "" then
  39                         self:set_node({name = staticdata})
  40                 end
  41         end,
  42
  43         on_step = function(self, dtime)
  44                  -- Set gravity
  45                 local acceleration = self.object:getacceleration()
  46                 if not vector.equals(acceleration, {x = 0, y = -10, z = 0}) then
  47                         self.object:setacceleration({x = 0, y = -10, z = 0})
  48                 end
  49                 -- Turn to actual sand when collides to ground or just move
  50                 local pos = self.object:getpos()
  51                 local bcp = {x = pos.x, y = pos.y - 0.7, z = pos.z} -- Position of bottom center point
  52                 local bcn = core.get_node(bcp)
  53                 local bcd = core.registered_nodes[bcn.name]
  54                 -- Note: walkable is in the node definition, not in item groups
  55                 if not bcd or
  56                                 (bcd.walkable or
  57                                 (core.get_item_group(self.node.name, "float") ~= 0 and
  58                                 bcd.liquidtype ~= "none")) then
  59                         if bcd and bcd.leveled and
  60                                         bcn.name == self.node.name then
  61                                 local addlevel = self.node.level
  62                                 if not addlevel or addlevel <= 0 then
  63                                         addlevel = bcd.leveled
  64                                 end
  65                                 if core.add_node_level(bcp, addlevel) == 0 then
  66                                         self.object:remove()
  67                                         return
  68                                 end
  69                         elseif bcd and bcd.buildable_to and
  70                                         (core.get_item_group(self.node.name, "float") == 0 or
  71                                         bcd.liquidtype == "none") then
  72                                 core.remove_node(bcp)
  73                                 return
  74                         end
  75                         local np = {x = bcp.x, y = bcp.y + 1, z = bcp.z}
  76                         -- Check what's here
  77                         local n2 = core.get_node(np)
  78                         -- If it's not air or liquid, remove node and replace it with
  79                         -- it's drops
  80                         if n2.name ~= "air" and (not core.registered_nodes[n2.name] or
  81                                         core.registered_nodes[n2.name].liquidtype == "none") then
  82                                 core.remove_node(np)
  83                                 if core.registered_nodes[n2.name].buildable_to == false then
  84                                         -- Add dropped items
  85                                         local drops = core.get_node_drops(n2.name, "")
  86                                         for _, dropped_item in ipairs(drops) do
  87                                                 core.add_item(np, dropped_item)
  88                                         end
  89                                 end
  90                                 -- Run script hook
  91                                 for _, callback in ipairs(core.registered_on_dignodes) do
  92                                         callback(np, n2)
  93                                 end
  94                         end
  95                         -- Create node and remove entity
  96                         if core.registered_nodes[self.node.name] then
  97                                 core.add_node(np, self.node)
  98                         end
  99                         self.object:remove()
 100                         nodeupdate(np)
 101                         return
 102                 end
 103                 local vel = self.object:getvelocity()
 104                 if vector.equals(vel, {x = 0, y = 0, z = 0}) then
 105                         local npos = self.object:getpos()
 106                         self.object:setpos(vector.round(npos))
 107                 end
 108         end
 109 })
 110
 111 function spawn_falling_node(p, node)
 112         local obj = core.add_entity(p, "__builtin:falling_node")
 113         obj:get_luaentity():set_node(node)
 114 end
 115
 116 function drop_attached_node(p)
 117         local nn = core.get_node(p).name
 118         core.remove_node(p)
 119         for _, item in ipairs(core.get_node_drops(nn, "")) do
 120                 local pos = {
 121                         x = p.x + math.random()/2 - 0.25,
 122                         y = p.y + math.random()/2 - 0.25,
 123                         z = p.z + math.random()/2 - 0.25,
 124                 }
 125                 core.add_item(pos, item)
 126         end
 127 end
 128
 129 function check_attached_node(p, n)
 130         local def = core.registered_nodes[n.name]
 131         local d = {x = 0, y = 0, z = 0}
 132         if def.paramtype2 == "wallmounted" then
 133                 d = core.wallmounted_to_dir(n.param2)
 134         else
 135                 d.y = -1
 136         end
 137         local p2 = vector.add(p, d)
 138         local nn = core.get_node(p2).name
 139         local def2 = core.registered_nodes[nn]
 140         if def2 and not def2.walkable then
 141                 return false
 142         end
 143         return true
 144 end
 145
 146 --
 147 -- Some common functions
 148 --
 149
 150 function nodeupdate_single(p, delay)
 151         local n = core.get_node(p)
 152         if core.get_item_group(n.name, "falling_node") ~= 0 then
 153                 local p_bottom = {x = p.x, y = p.y - 1, z = p.z}
 154                 local n_bottom = core.get_node(p_bottom)
 155                 -- Note: walkable is in the node definition, not in item groups
 156                 if core.registered_nodes[n_bottom.name] and
 157                                 (core.get_item_group(n.name, "float") == 0 or
 158                                         core.registered_nodes[n_bottom.name].liquidtype == "none") and
 159                                 (n.name ~= n_bottom.name or (core.registered_nodes[n_bottom.name].leveled and
 160                                         core.get_node_level(p_bottom) < core.get_node_max_level(p_bottom))) and
 161                                 (not core.registered_nodes[n_bottom.name].walkable or
 162                                         core.registered_nodes[n_bottom.name].buildable_to) then
 163                         if delay then
 164                                 core.after(0.1, nodeupdate_single, p, false)
 165                         else
 166                                 n.level = core.get_node_level(p)
 167                                 core.remove_node(p)
 168                                 spawn_falling_node(p, n)
 169                                 nodeupdate(p)
 170                         end
 171                 end
 172         end
 173
 174         if core.get_item_group(n.name, "attached_node") ~= 0 then
 175                 if not check_attached_node(p, n) then
 176                         drop_attached_node(p)
 177                         nodeupdate(p)
 178                 end
 179         end
 180 end
 181
 182 function nodeupdate(p, delay)
 183         -- Round p to prevent falling entities to get stuck
 184         p = vector.round(p)
 185
 186         for x = -1, 1 do
 187         for y = -1, 1 do
 188         for z = -1, 1 do
 189                 local d = vector.new(x, y, z)
 190                 nodeupdate_single(vector.add(p, d), delay or not (x == 0 and y == 0 and z == 0))
 191         end
 192         end
 193         end
 194 end
 195
 196 --
 197 -- Global callbacks
 198 --
 199
 200 function on_placenode(p, node)
 201         nodeupdate(p)
 202 end
 203 core.register_on_placenode(on_placenode)
 204
 205 function on_dignode(p, node)
 206         nodeupdate(p)
 207 end
 208 core.register_on_dignode(on_dignode)