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                         local np = {x=bcp.x, y=bcp.y+1, z=bcp.z}
  61                         -- Check what's here
  62                         local n2 = minetest.env:get_node(np)
  63                         -- If it's not air or liquid, remove node and replace it with
  64                         -- it's drops
  65                         if n2.name ~= "air" and (not minetest.registered_nodes[n2.name] or
  66                                         minetest.registered_nodes[n2.name].liquidtype == "none") then
  67                                 local drops = minetest.get_node_drops(n2.name, "")
  68                                 minetest.env:remove_node(np)
  69                                 -- Add dropped items
  70                                 local _, dropped_item
  71                                 for _, dropped_item in ipairs(drops) do
  72                                         minetest.env:add_item(np, dropped_item)
  73                                 end
  74                                 -- Run script hook
  75                                 local _, callback
  76                                 for _, callback in ipairs(minetest.registered_on_dignodes) do
  77                                         callback(np, n2, nil)
  78                                 end
  79                         end
  80                         -- Create node and remove entity
  81                         minetest.env:add_node(np, {name=self.nodename})
  82                         self.object:remove()
  83                 else
  84                         -- Do nothing
  85                 end
  86         end
  87 })
  88
  89 function spawn_falling_node(p, nodename)
  90         obj = minetest.env:add_entity(p, "__builtin:falling_node")
  91         obj:get_luaentity():set_node(nodename)
  92 end
  93
  94 function drop_attached_node(p)
  95         local nn = minetest.env:get_node(p).name
  96         minetest.env:remove_node(p)
  97         for _,item in ipairs(minetest.get_node_drops(nn, "")) do
  98                 local pos = {
  99                         x = p.x + math.random()/2 - 0.25,
 100                         y = p.y + math.random()/2 - 0.25,
 101                         z = p.z + math.random()/2 - 0.25,
 102                 }
 103                 minetest.env:add_item(pos, item)
 104         end
 105 end
 106
 107 function check_attached_node(p, n)
 108         local def = minetest.registered_nodes[n.name]
 109         local d = {x=0, y=0, z=0}
 110         if def.paramtype2 == "wallmounted" then
 111                 if n.param2 == 0 then
 112                         d.y = 1
 113                 elseif n.param2 == 1 then
 114                         d.y = -1
 115                 elseif n.param2 == 2 then
 116                         d.x = 1
 117                 elseif n.param2 == 3 then
 118                         d.x = -1
 119                 elseif n.param2 == 4 then
 120                         d.z = 1
 121                 elseif n.param2 == 5 then
 122                         d.z = -1
 123                 end
 124         else
 125                 d.y = -1
 126         end
 127         local p2 = {x=p.x+d.x, y=p.y+d.y, z=p.z+d.z}
 128         local nn = minetest.env:get_node(p2).name
 129         local def2 = minetest.registered_nodes[nn]
 130         if def2 and not def2.walkable then
 131                 return false
 132         end
 133         return true
 134 end
 135
 136 --
 137 -- Some common functions
 138 --
 139
 140 function nodeupdate_single(p)
 141         n = minetest.env:get_node(p)
 142         if minetest.get_node_group(n.name, "falling_node") ~= 0 then
 143                 p_bottom = {x=p.x, y=p.y-1, z=p.z}
 144                 n_bottom = minetest.env:get_node(p_bottom)
 145                 -- Note: walkable is in the node definition, not in item groups
 146                 if minetest.registered_nodes[n_bottom.name] and
 147                                 not minetest.registered_nodes[n_bottom.name].walkable then
 148                         minetest.env:remove_node(p)
 149                         spawn_falling_node(p, n.name)
 150                         nodeupdate(p)
 151                 end
 152         end
 153
 154         if minetest.get_node_group(n.name, "attached_node") ~= 0 then
 155                 if not check_attached_node(p, n) then
 156                         drop_attached_node(p)
 157                         nodeupdate(p)
 158                 end
 159         end
 160 end
 161
 162 function nodeupdate(p)
 163         -- Round p to prevent falling entities to get stuck
 164         p.x = math.floor(p.x+0.5)
 165         p.y = math.floor(p.y+0.5)
 166         p.z = math.floor(p.z+0.5)
 167
 168         for x = -1,1 do
 169         for y = -1,1 do
 170         for z = -1,1 do
 171                 p2 = {x=p.x+x, y=p.y+y, z=p.z+z}
 172                 nodeupdate_single(p2)
 173         end
 174         end
 175         end
 176 end
 177
 178 --
 179 -- Global callbacks
 180 --
 181
 182 function on_placenode(p, node)
 183         nodeupdate(p)
 184 end
 185 minetest.register_on_placenode(on_placenode)
 186
 187 function on_dignode(p, node)
 188         nodeupdate(p)
 189 end
 190 minetest.register_on_dignode(on_dignode)