builtin/falling.lua

   1 -- Minetest: builtin/item.lua
   2
   3 --
   4 -- Falling stuff
   5 --
   6
   7 minetest.register_entity("__builtin:falling_node", {
   8         initial_properties = {
   9                 physical = true,
  10                 collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},
  11                 visual = "wielditem",
  12                 textures = {},
  13                 visual_size = {x=0.667, y=0.667},
  14         },
  15
  16         nodename = "",
  17
  18         set_node = function(self, nodename)
  19                 self.nodename = nodename
  20                 local stack = ItemStack(nodename)
  21                 local itemtable = stack:to_table()
  22                 local itemname = nil
  23                 if itemtable then
  24                         itemname = stack:to_table().name
  25                 end
  26                 local item_texture = nil
  27                 local item_type = ""
  28                 if minetest.registered_items[itemname] then
  29                         item_texture = minetest.registered_items[itemname].inventory_image
  30                         item_type = minetest.registered_items[itemname].type
  31                 end
  32                 prop = {
  33                         is_visible = true,
  34                         textures = {nodename},
  35                 }
  36                 self.object:set_properties(prop)
  37         end,
  38
  39         get_staticdata = function(self)
  40                 return self.nodename
  41         end,
  42
  43         on_activate = function(self, staticdata)
  44                 self.nodename = staticdata
  45                 self.object:set_armor_groups({immortal=1})
  46                 --self.object:setacceleration({x=0, y=-10, z=0})
  47                 self:set_node(self.nodename)
  48         end,
  49
  50         on_step = function(self, dtime)
  51                 -- Set gravity
  52                 self.object:setacceleration({x=0, y=-10, z=0})
  53                 -- Turn to actual sand when collides to ground or just move
  54                 local pos = self.object:getpos()
  55                 local bcp = {x=pos.x, y=pos.y-0.7, z=pos.z} -- Position of bottom center point
  56                 local bcn = minetest.env:get_node(bcp)
  57                 -- Note: walkable is in the node definition, not in item groups
  58                 if minetest.registered_nodes[bcn.name] and
  59                                 minetest.registered_nodes[bcn.name].walkable then
  60                         if minetest.registered_nodes[bcn.name].buildable_to then
  61                                 minetest.env:remove_node(bcp)
  62                                 return
  63                         end
  64                         local np = {x=bcp.x, y=bcp.y+1, z=bcp.z}
  65                         -- Check what's here
  66                         local n2 = minetest.env:get_node(np)
  67                         -- If it's not air or liquid, remove node and replace it with
  68                         -- it's drops
  69                         if n2.name ~= "air" and (not minetest.registered_nodes[n2.name] or
  70                                         minetest.registered_nodes[n2.name].liquidtype == "none") then
  71                                 local drops = minetest.get_node_drops(n2.name, "")
  72                                 minetest.env:remove_node(np)
  73                                 -- Add dropped items
  74                                 local _, dropped_item
  75                                 for _, dropped_item in ipairs(drops) do
  76                                         minetest.env:add_item(np, dropped_item)
  77                                 end
  78                                 -- Run script hook
  79                                 local _, callback
  80                                 for _, callback in ipairs(minetest.registered_on_dignodes) do
  81                                         callback(np, n2, nil)
  82                                 end
  83                         end
  84                         -- Create node and remove entity
  85                         minetest.env:add_node(np, {name=self.nodename})
  86                         self.object:remove()
  87                         nodeupdate(np)
  88                 else
  89                         -- Do nothing
  90                 end
  91         end
  92 })
  93
  94 function spawn_falling_node(p, nodename)
  95         obj = minetest.env:add_entity(p, "__builtin:falling_node")
  96         obj:get_luaentity():set_node(nodename)
  97 end
  98
  99 function drop_attached_node(p)
 100         local nn = minetest.env:get_node(p).name
 101         minetest.env:remove_node(p)
 102         for _,item in ipairs(minetest.get_node_drops(nn, "")) do
 103                 local pos = {
 104                         x = p.x + math.random()/2 - 0.25,
 105                         y = p.y + math.random()/2 - 0.25,
 106                         z = p.z + math.random()/2 - 0.25,
 107                 }
 108                 minetest.env:add_item(pos, item)
 109         end
 110 end
 111
 112 function check_attached_node(p, n)
 113         local def = minetest.registered_nodes[n.name]
 114         local d = {x=0, y=0, z=0}
 115         if def.paramtype2 == "wallmounted" then
 116                 if n.param2 == 0 then
 117                         d.y = 1
 118                 elseif n.param2 == 1 then
 119                         d.y = -1
 120                 elseif n.param2 == 2 then
 121                         d.x = 1
 122                 elseif n.param2 == 3 then
 123                         d.x = -1
 124                 elseif n.param2 == 4 then
 125                         d.z = 1
 126                 elseif n.param2 == 5 then
 127                         d.z = -1
 128                 end
 129         else
 130                 d.y = -1
 131         end
 132         local p2 = {x=p.x+d.x, y=p.y+d.y, z=p.z+d.z}
 133         local nn = minetest.env:get_node(p2).name
 134         local def2 = minetest.registered_nodes[nn]
 135         if def2 and not def2.walkable then
 136                 return false
 137         end
 138         return true
 139 end
 140
 141 --
 142 -- Some common functions
 143 --
 144
 145 function nodeupdate_single(p, delay)
 146         n = minetest.env:get_node(p)
 147         if minetest.get_node_group(n.name, "falling_node") ~= 0 then
 148                 p_bottom = {x=p.x, y=p.y-1, z=p.z}
 149                 n_bottom = minetest.env:get_node(p_bottom)
 150                 -- Note: walkable is in the node definition, not in item groups
 151                 if minetest.registered_nodes[n_bottom.name] and
 152                                 (not minetest.registered_nodes[n_bottom.name].walkable or
 153                                         minetest.registered_nodes[n_bottom.name].buildable_to) then
 154                         if delay then
 155                                 minetest.after(0.1, nodeupdate_single, {x=p.x, y=p.y, z=p.z}, false)
 156                         else
 157                                 minetest.env:remove_node(p)
 158                                 spawn_falling_node(p, n.name)
 159                                 nodeupdate(p)
 160                         end
 161                 end
 162         end
 163
 164         if minetest.get_node_group(n.name, "attached_node") ~= 0 then
 165                 if not check_attached_node(p, n) then
 166                         drop_attached_node(p)
 167                         nodeupdate(p)
 168                 end
 169         end
 170 end
 171
 172 function nodeupdate(p)
 173         -- Round p to prevent falling entities to get stuck
 174         p.x = math.floor(p.x+0.5)
 175         p.y = math.floor(p.y+0.5)
 176         p.z = math.floor(p.z+0.5)
 177
 178         for x = -1,1 do
 179         for y = -1,1 do
 180         for z = -1,1 do
 181                 nodeupdate_single({x=p.x+x, y=p.y+y, z=p.z+z}, not (x==0 and y==0 and z==0))
 182         end
 183         end
 184         end
 185 end
 186
 187 --
 188 -- Global callbacks
 189 --
 190
 191 function on_placenode(p, node)
 192         nodeupdate(p)
 193 end
 194 minetest.register_on_placenode(on_placenode)
 195
 196 function on_dignode(p, node)
 197         nodeupdate(p)
 198 end
 199 minetest.register_on_dignode(on_dignode)