Refactor code and fix bugs

[minetest_schemedit.git] / init.lua

-- advschem/init.lua

local advschem = {}

-- Directory delimeter fallback (normally comes from builtin)
if not DIR_DELIM then
        DIR_DELIM = "/"
end
local export_path_full = table.concat({minetest.get_worldpath(), "schems"}, DIR_DELIM)

local text_color = "#D79E9E"
local text_color_number = 0xD79E9E

advschem.markers = {}

-- [local function] Renumber table
local function renumber(t)
        local res = {}
        for _, i in pairs(t) do
                res[#res + 1] = i
        end
        return res
end

---
--- Formspec API
---

local contexts = {}
local form_data = {}
local tabs = {}
local forms = {}
local displayed_waypoints = {}

-- [function] Add form
function advschem.add_form(name, def)
        def.name = name
        forms[name] = def

        if def.tab then
                tabs[#tabs + 1] = name
        end
end

-- [function] Generate tabs
function advschem.generate_tabs(current)
        local retval = "tabheader[0,0;tabs;"
        for _, t in pairs(tabs) do
                local f = forms[t]
                if f.tab ~= false and f.caption then
                        retval = retval..f.caption..","

                        if type(current) ~= "number" and current == f.name then
                                current = _
                        end
                end
        end
        retval = retval:sub(1, -2) -- Strip last comma
        retval = retval..";"..current.."]" -- Close tabheader
        return retval
end

-- [function] Handle tabs
function advschem.handle_tabs(pos, name, fields)
        local tab = tonumber(fields.tabs)
        if tab and tabs[tab] and forms[tabs[tab]] then
                advschem.show_formspec(pos, name, forms[tabs[tab]].name)
                return true
        end
end

-- [function] Show formspec
function advschem.show_formspec(pos, player, tab, show, ...)
        if forms[tab] then
                if type(player) == "string" then
                        player = minetest.get_player_by_name(player)
                end
                local name = player:get_player_name()

                if show ~= false then
                        if not form_data[name] then
                                form_data[name] = {}
                        end

                        local form = forms[tab].get(form_data[name], pos, name, ...)
                        if forms[tab].tab then
                                form = form..advschem.generate_tabs(tab)
                        end

                        minetest.show_formspec(name, "advschem:"..tab, form)
                        contexts[name] = pos

                        -- Update player attribute
                        if forms[tab].cache_name ~= false then
                                player:set_attribute("advschem:tab", tab)
                        end
                else
                        minetest.close_formspec(pname, "advschem:"..tab)
                end
        end
end

-- [event] On receive fields
minetest.register_on_player_receive_fields(function(player, formname, fields)
        local formname = formname:split(":")

        if formname[1] == "advschem" and forms[formname[2]] then
                local handle = forms[formname[2]].handle
                local name = player:get_player_name()
                if contexts[name] then
                        if not form_data[name] then
                                form_data[name] = {}
                        end

                        if not advschem.handle_tabs(contexts[name], name, fields) and handle then
                                handle(form_data[name], contexts[name], name, fields)
                        end
                end
        end
end)

-- Helper function. Scans probabilities of all nodes in the given area and returns a prob_list
advschem.scan_metadata = function(pos1, pos2)
        local prob_list = {}

        for x=pos1.x, pos2.x do
        for y=pos1.y, pos2.y do
        for z=pos1.z, pos2.z do
                local scanpos = {x=x, y=y, z=z}
                local node = minetest.get_node_or_nil(scanpos)

                local prob, force_place
                if node == nil or node.name == "advschem:void" then
                        prob = 0
                        force_place = false
                else
                        local meta = minetest.get_meta(scanpos)

                        prob = tonumber(meta:get_string("advschem_prob")) or 127
                        local fp = meta:get_string("advschem_force_place")
                        if fp == "true" then
                                force_place = true
                        else
                                force_place = false
                        end
                end

                local ostrpos = minetest.pos_to_string(scanpos)
                prob_list[ostrpos] = {
                        pos = scanpos,
                        prob = prob,
                        force_place = force_place,
                }
        end
        end
        end

        return prob_list
end

-- Sets probability and force_place metadata of an item.
-- Also updates item description.
-- The itemstack is updated in-place.
local function set_item_metadata(itemstack, prob, force_place)
        local smeta = itemstack:get_meta()
        local prob_desc = "\nProbability: "..(prob) or
                        smeta:get_string("advschem_prob") or "Not Set"
        -- Update probability
        if prob and prob >= 0 and prob < 127 then
                smeta:set_string("advschem_prob", tostring(prob))
        elseif prob and prob == 127 then
                -- Clear prob metadata for default probability
                prob_desc = ""
                smeta:set_string("advschem_prob", nil)
        else
                prob_desc = "\nProbability: "..(smeta:get_string("advschem_prob") or
                                "Not Set")
        end

        -- Update force place
        if force_place == true then
                smeta:set_string("advschem_force_place", "true")
        elseif force_place == false then
                smeta:set_string("advschem_force_place", nil)
        end

        -- Update description
        local desc = minetest.registered_items[itemstack:get_name()].description
        local meta_desc = smeta:get_string("description")
        if meta_desc and meta_desc ~= "" then
                desc = meta_desc
        end

        local original_desc = smeta:get_string("original_description")
        if original_desc and original_desc ~= "" then
                desc = original_desc
        else
                smeta:set_string("original_description", desc)
        end

        local force_desc = ""
        if smeta:get_string("advschem_force_place") == "true" then
                force_desc = "\n".."Force placement"
        end

        desc = desc..minetest.colorize(text_color, prob_desc..force_desc)

        smeta:set_string("description", desc)

        return itemstack
end

---
--- Formspec Tabs
---

advschem.add_form("main", {
        tab = true,
        caption = "Main",
        get = function(self, pos, name)
                local meta = minetest.get_meta(pos):to_table().fields
                local strpos = minetest.pos_to_string(pos)

                local border_button
                if meta.schem_border == "true" and advschem.markers[strpos] then
                        border_button = "button[3.5,7.5;3,1;border;Hide border]"
                else
                        border_button = "button[3.5,7.5;3,1;border;Show border]"
                end

                -- TODO: Show information regarding volume, pos1, pos2, etc... in formspec
                return [[
                        size[7,8]
                        label[0.5,-0.1;Position: ]]..strpos..[[]
                        label[3,-0.1;Owner: ]]..name..[[]

                        field[0.8,1;5,1;name;Schematic name:;]]..minetest.formspec_escape(meta.schem_name or "")..[[]
                        button[5.3,0.69;1.2,1;save_name;Save]
                        tooltip[save_name;Save schematic name]
                        field_close_on_enter[name;false]

                        button[0.5,1.5;6,1;export;Export schematic]
                        textarea[0.8,2.5;6.2,5;;The schematic will be exported as a .mts file and stored in]]..
                        "\n" .. export_path_full .. DIR_DELIM .. [[<name>.mts.;]
                        field[0.8,7;2,1;x;X size:;]]..meta.x_size..[[]
                        field[2.8,7;2,1;y;Y size:;]]..meta.y_size..[[]
                        field[4.8,7;2,1;z;Z size:;]]..meta.z_size..[[]
                        field_close_on_enter[x;false]
                        field_close_on_enter[y;false]
                        field_close_on_enter[z;false]

                        button[0.5,7.5;3,1;save;Save size]
                ]]..
                border_button
        end,
        handle = function(self, pos, name, fields)
                local realmeta = minetest.get_meta(pos)
                local meta = realmeta:to_table().fields
                local strpos = minetest.pos_to_string(pos)

                -- Toggle border
                if fields.border then
                        if meta.schem_border == "true" and advschem.markers[strpos] then
                                advschem.unmark(pos)
                                meta.schem_border = "false"
                        else
                                advschem.mark(pos)
                                meta.schem_border = "true"
                        end
                end

                -- Save size vector values
                if (fields.save or fields.key_enter_field == "x" or
                                fields.key_enter_field == "y" or fields.key_enter_field == "z")
                                and (fields.x and fields.y and fields.z and fields.x ~= ""
                                and fields.y ~= "" and fields.z ~= "") then
                        local x, y, z = tonumber(fields.x), tonumber(fields.y), tonumber(fields.z)

                        if x then
                                meta.x_size = math.max(x, 1)
                        end
                        if y then
                                meta.y_size = math.max(y, 1)
                        end
                        if z then
                                meta.z_size = math.max(z, 1)
                        end
                end

                -- Save schematic name
                if fields.save_name or fields.key_enter_field == "name" and fields.name and
                                fields.name ~= "" then
                        meta.schem_name = fields.name
                end

                -- Export schematic
                if fields.export and meta.schem_name and meta.schem_name ~= "" then
                        local pos1, pos2 = advschem.size(pos)
                        pos1, pos2 = advschem.sort_pos(pos1, pos2)
                        local path = export_path_full .. DIR_DELIM
                        minetest.mkdir(path)

                        local plist = advschem.scan_metadata(pos1, pos2)
                        local probability_list = {}
                        for _, i in pairs(plist) do
                                local prob = i.prob
                                if i.force_place == true then
                                        prob = prob + 128
                                end

                                probability_list[#probability_list + 1] = {
                                        pos = minetest.string_to_pos(_),
                                        prob = prob,
                                }
                        end

                        local slist = minetest.deserialize(meta.slices)
                        local slice_list = {}
                        for _, i in pairs(slist) do
                                slice_list[#slice_list + 1] = {
                                        ypos = pos.y + i.ypos,
                                        prob = i.prob,
                                }
                        end

                        local filepath = path..meta.schem_name..".mts"
                        local res = minetest.create_schematic(pos1, pos2, probability_list, filepath, slice_list)

                        if res then
                                minetest.chat_send_player(name, minetest.colorize("#00ff00",
                                                "Exported schematic to "..filepath))
                        else
                                minetest.chat_send_player(name, minetest.colorize("red",
                                                "Failed to export schematic to "..filepath))
                        end
                end

                -- Save meta before updating visuals
                local inv = realmeta:get_inventory():get_lists()
                realmeta:from_table({fields = meta, inventory = inv})

                -- Update border
                if not fields.border and meta.schem_border == "true" then
                        advschem.mark(pos)
                end

                -- Update formspec
                if not fields.quit then
                        advschem.show_formspec(pos, minetest.get_player_by_name(name), "main")
                end
        end,
})

advschem.add_form("slice", {
        caption = "Y Slices",
        tab = true,
        get = function(self, pos, name, visible_panel)
                local meta = minetest.get_meta(pos):to_table().fields

                self.selected = self.selected or 1
                local selected = tostring(self.selected)
                local slice_list = minetest.deserialize(meta.slices)
                local slices = ""
                for _, i in pairs(slice_list) do
                        local insert = "Y = "..tostring(i.ypos).."; Probability = "..tostring(i.prob)
                        slices = slices..minetest.formspec_escape(insert)..","
                end
                slices = slices:sub(1, -2) -- Remove final comma

                local form = [[
                        size[7,8]
                        table[0,0;6.8,6;slices;]]..slices..[[;]]..selected..[[]
                ]]

                if self.panel_add or self.panel_edit then
                        local ypos_default, prob_default = "", ""
                        local done_button = "button[5,7.18;2,1;done_add;Done]"
                        if self.panel_edit then
                                done_button = "button[5,7.18;2,1;done_edit;Done]"
                                ypos_default = slice_list[self.selected].ypos
                                prob_default = slice_list[self.selected].prob
                        end

                        form = form..[[
                                field[0.3,7.5;2.5,1;ypos;Y position (max. ]]..(meta.y_size - 1)..[[):;]]..ypos_default..[[]
                                field[2.8,7.5;2.5,1;prob;Probability (0-127):;]]..prob_default..[[]
                                field_close_on_enter[ypos;false]
                                field_close_on_enter[prob;false]
                        ]]..done_button
                end

                if not self.panel_edit then
                        form = form.."button[0,6;2,1;add;+ Add slice]"
                end

                if slices ~= "" and self.selected and not self.panel_add then
                        if not self.panel_edit then
                                form = form..[[
                                        button[2,6;2,1;remove;- Remove slice]
                                        button[4,6;2,1;edit;+/- Edit slice]
                                ]]
                        else
                                form = form..[[
                                        button[2,6;2,1;remove;- Remove slice]
                                        button[4,6;2,1;edit;+/- Edit slice]
                                ]]
                        end
                end

                return form
        end,
        handle = function(self, pos, name, fields)
                local meta = minetest.get_meta(pos)
                local player = minetest.get_player_by_name(name)

                if fields.slices then
                        local slices = fields.slices:split(":")
                        self.selected = tonumber(slices[2])
                end

                if fields.add then
                        if not self.panel_add then
                                self.panel_add = true
                                advschem.show_formspec(pos, player, "slice")
                        else
                                self.panel_add = nil
                                advschem.show_formspec(pos, player, "slice")
                        end
                end

                local ypos, prob = tonumber(fields.ypos), tonumber(fields.prob)
                if (fields.done_add or fields.done_edit) and fields.ypos and fields.prob and
                fields.ypos ~= "" and fields.prob ~= "" and ypos and prob and
                                 ypos <= (meta:get_int("y_size") - 1) and prob >= 0 and prob <= 255 then
                        local slice_list = minetest.deserialize(meta:get_string("slices"))
                        local index = #slice_list + 1
                        if fields.done_edit then
                                index = self.selected
                        end

                        slice_list[index] = {ypos = ypos, prob = prob}

                        meta:set_string("slices", minetest.serialize(slice_list))

                        -- Update and show formspec
                        self.panel_add = nil
                        advschem.show_formspec(pos, player, "slice")
                end

                if fields.remove and self.selected then
                        local slice_list = minetest.deserialize(meta:get_string("slices"))
                        slice_list[self.selected] = nil
                        meta:set_string("slices", minetest.serialize(renumber(slice_list)))

                        -- Update formspec
                        self.selected = 1
                        self.panel_edit = nil
                        advschem.show_formspec(pos, player, "slice")
                end

                if fields.edit then
                        if not self.panel_edit then
                                self.panel_edit = true
                                advschem.show_formspec(pos, player, "slice")
                        else
                                self.panel_edit = nil
                                advschem.show_formspec(pos, player, "slice")
                        end
                end
        end,
})

advschem.add_form("probtool", {
        cache_name = false,
        caption = "Schematic Node Probability Tool",
        get = function(self, pos, name)
                local player = minetest.get_player_by_name(name)
                if not player then
                        return
                end
                local probtool = player:get_wielded_item()
                if probtool:get_name() ~= "advschem:probtool" then
                        return
                end

                local meta = probtool:get_meta()
                local prob = tonumber(meta:get_string("advschem_prob"))
                local force_place = meta:get_string("advschem_force_place")

                if not prob then
                        prob = 127
                end
                if force_place == nil or force_place == "" then
                        force_place = "false"
                end
                local form = "size[5,4]"..
                        "label[0,0;Schematic Node Probability Tool]"..
                        "field[0.75,1;4,1;prob;Probability (0-127);"..prob.."]"..
                        "checkbox[0.60,1.5;force_place;Force placement;" .. force_place .. "]" ..
                        "button_exit[0.25,3;2,1;cancel;Cancel]"..
                        "button_exit[2.75,3;2,1;submit;Apply]"..
                        "tooltip[prob;Probability that the node will be placed]"..
                        "tooltip[force_place;If enabled, the node will replace nodes other than air and ignore]"..
                        "field_close_on_enter[prob;false]"
                return form
        end,
        handle = function(self, pos, name, fields)
                if fields.submit then
                        local prob = tonumber(fields.prob)
                        if prob then
                                local player = minetest.get_player_by_name(name)
                                if not player then
                                        return
                                end
                                local probtool = player:get_wielded_item()
                                if probtool:get_name() ~= "advschem:probtool" then
                                        return
                                end

                                local force_place = self.force_place == true

                                set_item_metadata(probtool, prob, force_place)

                                player:set_wielded_item(probtool)
                        end
                end
                if fields.force_place == "true" then
                        self.force_place = true
                elseif fields.force_place == "false" then
                        self.force_place = false
                end
        end,
})

---
--- API
---

--- Copies and modifies positions `pos1` and `pos2` so that each component of
-- `pos1` is less than or equal to the corresponding component of `pos2`.
-- Returns the new positions.
function advschem.sort_pos(pos1, pos2)
        if not pos1 or not pos2 then
                return
        end

        pos1, pos2 = table.copy(pos1), table.copy(pos2)
        if pos1.x > pos2.x then
                pos2.x, pos1.x = pos1.x, pos2.x
        end
        if pos1.y > pos2.y then
                pos2.y, pos1.y = pos1.y, pos2.y
        end
        if pos1.z > pos2.z then
                pos2.z, pos1.z = pos1.z, pos2.z
        end
        return pos1, pos2
end

-- [function] Prepare size
function advschem.size(pos)
        local pos1   = vector.new(pos)
        local meta   = minetest.get_meta(pos)
        local node   = minetest.get_node(pos)
        local param2 = node.param2
        local size   = {
                x = meta:get_int("x_size"),
                y = math.max(meta:get_int("y_size") - 1, 0),
                z = meta:get_int("z_size"),
        }

        if param2 == 1 then
                local new_pos = vector.add({x = size.z, y = size.y, z = -size.x}, pos)
                pos1.x = pos1.x + 1
                new_pos.z = new_pos.z + 1
                return pos1, new_pos
        elseif param2 == 2 then
                local new_pos = vector.add({x = -size.x, y = size.y, z = -size.z}, pos)
                pos1.z = pos1.z - 1
                new_pos.x = new_pos.x + 1
                return pos1, new_pos
        elseif param2 == 3 then
                local new_pos = vector.add({x = -size.z, y = size.y, z = size.x}, pos)
                pos1.x = pos1.x - 1
                new_pos.z = new_pos.z - 1
                return pos1, new_pos
        else
                local new_pos = vector.add(size, pos)
                pos1.z = pos1.z + 1
                new_pos.x = new_pos.x - 1
                return pos1, new_pos
        end
end

-- [function] Mark region
function advschem.mark(pos)
        advschem.unmark(pos)

        local id = minetest.pos_to_string(pos)
        local owner = minetest.get_meta(pos):get_string("owner")
        local pos1, pos2 = advschem.size(pos)
        pos1, pos2 = advschem.sort_pos(pos1, pos2)

        local thickness = 0.2
        local sizex, sizey, sizez = (1 + pos2.x - pos1.x) / 2, (1 + pos2.y - pos1.y) / 2, (1 + pos2.z - pos1.z) / 2
        local m = {}
        local low = true
        local offset

        -- XY plane markers
        for _, z in ipairs({pos1.z - 0.5, pos2.z + 0.5}) do
                if low then
                        offset = -0.01
                else
                        offset = 0.01
                end
                local marker = minetest.add_entity({x = pos1.x + sizex - 0.5, y = pos1.y + sizey - 0.5, z = z + offset}, "advschem:display")
                if marker ~= nil then
                        marker:set_properties({
                                visual_size={x=(sizex+0.01) * 2, y=sizey * 2},
                        })
                        marker:get_luaentity().id = id
                        marker:get_luaentity().owner = owner
                        table.insert(m, marker)
                end
                low = false
        end

        low = true
        -- YZ plane markers
        for _, x in ipairs({pos1.x - 0.5, pos2.x + 0.5}) do
                if low then
                        offset = -0.01
                else
                        offset = 0.01
                end

                local marker = minetest.add_entity({x = x + offset, y = pos1.y + sizey - 0.5, z = pos1.z + sizez - 0.5}, "advschem:display")
                if marker ~= nil then
                        marker:set_properties({
                                visual_size={x=(sizez+0.01) * 2, y=sizey * 2},
                        })
                        marker:set_yaw(math.pi / 2)
                        marker:get_luaentity().id = id
                        marker:get_luaentity().owner = owner
                        table.insert(m, marker)
                end
                low = false
        end

        advschem.markers[id] = m
        return true
end

-- [function] Unmark region
function advschem.unmark(pos)
        local id = minetest.pos_to_string(pos)
        if advschem.markers[id] then
                local retval
                for _, entity in ipairs(advschem.markers[id]) do
                        entity:remove()
                        retval = true
                end
                return retval
        end
end

---
--- Mark node probability values near player
---

-- Show probability and force_place status of a particular position for player in HUD.
-- Probability is shown as a number followed by “[F]” if the node is force-placed.
-- The distance to the node is also displayed below that. This can't be avoided and is
-- and artifact of the waypoint HUD element. TODO: Hide displayed distance.
function advschem.display_node_prob(player, pos, prob, force_place)
        local wpstring
        if prob and force_place == true then
                wpstring = string.format("%d [F]", prob)
        elseif prob then
                wpstring = prob
        elseif force_place == true then
                wpstring = "[F]"
        end
        if wpstring then
                return player:hud_add({
                        hud_elem_type = "waypoint",
                        name = wpstring,
                        text = "m", -- For the distance artifact
                        number = text_color_number,
                        world_pos = pos,
                })
        end
end

-- Display the node probabilities and force_place status of the nodes near the player.
function advschem.display_node_probs_around_player(player)
        local playername = player:get_player_name()
        local pos = vector.round(player:getpos())
        local dist = 5
        for x=pos.x-dist, pos.x+dist do
                for y=pos.y-dist, pos.y+dist do
                        for z=pos.z-dist, pos.z+dist do
                                local checkpos = {x=x, y=y, z=z}
                                local nodehash = minetest.hash_node_position(checkpos)

                                -- If node is already displayed, remove it so it can re replaced later
                                if displayed_waypoints[playername][nodehash] then
                                        player:hud_remove(displayed_waypoints[playername][nodehash])
                                        displayed_waypoints[playername][nodehash] = nil
                                end

                                local prob, force_place
                                local meta = minetest.get_meta(checkpos)
                                prob = tonumber(meta:get_string("advschem_prob"))
                                force_place = meta:get_string("advschem_force_place") == "true"
                                local hud_id = advschem.display_node_prob(player, checkpos, prob, force_place)
                                if hud_id then
                                        displayed_waypoints[playername][nodehash] = hud_id
                                end
                        end
                end
        end
end

-- Remove all active displayed node statuses.
function advschem.clear_displayed_node_probs(player)
        for nodehash, hud_id in pairs(displayed_waypoints[player:get_player_name()]) do
                player:hud_remove(hud_id)
                displayed_waypoints[player:get_player_name()][nodehash] = nil
        end
end

minetest.register_on_joinplayer(function(player)
        displayed_waypoints[player:get_player_name()] = {}
end)

minetest.register_on_leaveplayer(function(player)
        displayed_waypoints[player:get_player_name()] = nil
end)

---
--- Registrations
---

-- [priv] schematic_override
minetest.register_privilege("schematic_override", {
        description = "Allows you to access advschem nodes not owned by you",
        give_to_singleplayer = false,
})

-- [node] Schematic creator
minetest.register_node("advschem:creator", {
        description = "Schematic Creator",
        _doc_items_longdesc = "The schematic creator is used to save a region of the world into a schematic file (.mts).",
        _doc_items_usagehelp = "To get started, place the block facing directly in front of any bottom left corner of the structure you want to save. This block can only be accessed by the placer or by anyone with the “schematic_override” privilege.".."\n"..
"To save a region, rightclick the block, enter the size, a schematic name and hit “Export schematic”. The file will always be saved in the world directory. You can use this name in the /placeschem command.".."\n"..
"The other features of the schematic creator are optional and are used to allow to add randomness and fine-tuning.".."\n"..
"Y slices are used to remove entire slices based on chance. For each slice of the schematic region along the Y axis, you can specify that it occours only with a certain chance. In the Y slice tab, you have to specify the Y slice height (0 = bottom) and a probability from 0 to 127 (127 is for 100%). By default, all Y slices occour always.".."\n"..
"With a schematic node probability tool, you can set a probability for each node and enable them to overwrite all nodes when placed as schematic. This tool must be used prior to the file export.",
        tiles = {"advschem_creator_top.png", "advschem_creator_bottom.png",
                        "advschem_creator_sides.png"},
        groups = { dig_immediate = 2},
        paramtype2 = "facedir",
        is_ground_content = false,

        after_place_node = function(pos, player)
                local name = player:get_player_name()
                local meta = minetest.get_meta(pos)

                meta:set_string("owner", name)
                meta:set_string("infotext", "Schematic Creator\n(owned by "..name..")")
                meta:set_string("prob_list", minetest.serialize({}))
                meta:set_string("slices", minetest.serialize({}))

                local node = minetest.get_node(pos)
                local dir  = minetest.facedir_to_dir(node.param2)

                meta:set_int("x_size", 1)
                meta:set_int("y_size", 1)
                meta:set_int("z_size", 1)

                -- Don't take item from itemstack
                return true
        end,
        can_dig = function(pos, player)
                local name = player:get_player_name()
                local meta = minetest.get_meta(pos)
                if meta:get_string("owner") == name or
                                minetest.check_player_privs(player, "schematic_override") == true then
                        return true
                end

                return false
        end,
        on_rightclick = function(pos, node, player)
                local meta = minetest.get_meta(pos)
                local name = player:get_player_name()
                if meta:get_string("owner") == name or
                                minetest.check_player_privs(player, "schematic_override") == true then
                        -- Get player attribute
                        local tab = player:get_attribute("advschem:tab")
                        if not forms[tab] or not tab then
                                tab = "main"
                        end

                        advschem.show_formspec(pos, player, tab, true)
                end
        end,
        after_destruct = function(pos)
                advschem.unmark(pos)
        end,
})

minetest.register_tool("advschem:probtool", {
        description = "Schematic Node Probability Tool",
        _doc_items_longdesc =
"This tool can be used together with a schematic creator to finetune the way how nodes from a schematic are placed.".."\n"..
"It allows you to do two things:".."\n"..
"1) Set a chance for a particular node not to be placed in schematic".."\n"..
"2) Enable a node to replace blocks other than air and ignored when placed in a schematic",
        _doc_items_usagehelp = "Leftclick to select a probability (0-127; 127 is for 100%) and to enable or disable force placement. Now rightclick any node with this tool to apply these settings to the node. This information is preserved in the node until it is destroyed or the tool is used again. Now you can use a schematic creator to save a region as usual, the nodes will now be saved with the special node settings applied.".."\n"..
"Note that this tool only has an effect on the nodes with regards to schematics. The node behaviour itself is not changed at all.",
        wield_image = "advschem_probtool.png",
        inventory_image = "advschem_probtool.png",
        on_use = function(itemstack, user, pointed_thing)
                -- Open dialog to change the probability to apply to nodes.
                advschem.show_formspec(user:getpos(), user, "probtool", true)
        end,
        on_secondary_use = function(itemstack, user, pointed_thing)
                advschem.clear_displayed_node_probs(user)
        end,
        on_place = function(itemstack, placer, pointed_thing)

                -- This sets the node probability of pointed node to the
                -- currently used probability stored in the tool.

                local pos = pointed_thing.under
                local node = minetest.get_node(pos)
                -- Schematic void are ignored, they always have probability 0
                if node.name == "advschem:void" then
                        return itemstack
                end
                local nmeta = minetest.get_meta(pos)
                local imeta = itemstack:get_meta()
                local prob = tonumber(imeta:get_string("advschem_prob"))
                local force_place = imeta:get_string("advschem_force_place")

                if not prob or prob == 127 then
                        nmeta:set_string("advschem_prob", nil)
                else
                        nmeta:set_string("advschem_prob", prob)
                end
                if force_place == "true" then
                        nmeta:set_string("advschem_force_place", "true")
                else
                        nmeta:set_string("advschem_force_place", nil)
                end

                -- Enable node probablity display
                advschem.display_node_probs_around_player(placer)

                return itemstack
        end,
})

minetest.register_node("advschem:void", {
        description = "Schematic Void",
        _doc_items_longdesc = "This is an utility block used in the creation of schematic files. It should be used together with a schematic creator. When saving a schematic, all nodes with a schematic void will be left unchanged when the schematic is placed again. Technically, this is equivalent to a block with the node probability set to 0.",
        _doc_items_usagehelp = "Just place the schematic void like any other block and use the schematic creator to save a portion of the world.",
        tiles = { "advschem_void.png" },
        drawtype = "nodebox",
        is_ground_content = false,
        paramtype = "light",
        walkable = false,
        sunlight_propagates = true,
        node_box = {
                type = "fixed",
                fixed = {
                        { -4/16, -4/16, -4/16, 4/16, 4/16, 4/16 },
                },
        },
        groups = { dig_immediate = 3},
})

-- [entity] Visible schematic border
minetest.register_entity("advschem:display", {
        visual = "upright_sprite",
        textures = {"advschem_border.png"},
        visual_size = {x=10, y=10},
        collisionbox = {0,0,0,0,0,0},
        physical = false,

        on_step = function(self, dtime)
                if not self.id then
                        self.object:remove()
                elseif not advschem.markers[self.id] then
                        self.object:remove()
                end
        end,
        on_activate = function(self)
                self.object:set_armor_groups({immortal = 1})
        end,
})

-- [chatcommand] Place schematic
minetest.register_chatcommand("placeschem", {
        description = "Place schematic at the position specified or the current "..
                        "player position (loaded from "..export_path_full..".",
        privs = {debug = true},
        params = "<schematic name>[.mts] [<x> <y> <z>]",
        func = function(name, param)
                local schem, p = string.match(param, "^([^ ]+) *(.*)$")
                local pos = minetest.string_to_pos(p)

                if not schem then
                        return false, "No schematic file specified."
                end

                if not pos then
                        pos = minetest.get_player_by_name(name):get_pos()
                end

                -- Automatiically add file name suffix if omitted
                local schem_full
                if string.sub(schem, string.len(schem)-3, string.len(schem)) == ".mts" then
                        schem_full = schem
                else
                        schem_full = schem .. ".mts"
                end

                local success = minetest.place_schematic(pos, export_path_full .. DIR_DELIM .. schem_full, "random", nil, false)

                if success == nil then
                        return false, "Schematic file could not be loaded!"
                else
                        return true
                end
        end,
})