minetest/builtin/game/misc.lua
Paramat 01bc817fe0 Intersects_protection(): Move from Minetest Game to builtin (#6952)
A useful function that applies 'core.is_protected()' to a 3D lattice of
points evenly spaced throughout a defined volume, with a parameter for
the maximum spacing of points.
2018-01-23 19:04:58 +01:00

253 lines
5.8 KiB
Lua

-- Minetest: builtin/misc.lua
--
-- Misc. API functions
--
function core.check_player_privs(name, ...)
local arg_type = type(name)
if (arg_type == "userdata" or arg_type == "table") and
name.get_player_name then -- If it quacks like a Player...
name = name:get_player_name()
elseif arg_type ~= "string" then
error("Invalid core.check_player_privs argument type: " .. arg_type, 2)
end
local requested_privs = {...}
local player_privs = core.get_player_privs(name)
local missing_privileges = {}
if type(requested_privs[1]) == "table" then
-- We were provided with a table like { privA = true, privB = true }.
for priv, value in pairs(requested_privs[1]) do
if value and not player_privs[priv] then
missing_privileges[#missing_privileges + 1] = priv
end
end
else
-- Only a list, we can process it directly.
for key, priv in pairs(requested_privs) do
if not player_privs[priv] then
missing_privileges[#missing_privileges + 1] = priv
end
end
end
if #missing_privileges > 0 then
return false, missing_privileges
end
return true, ""
end
local player_list = {}
function core.send_join_message(player_name)
if not minetest.is_singleplayer() then
core.chat_send_all("*** " .. player_name .. " joined the game.")
end
end
function core.send_leave_message(player_name, timed_out)
local announcement = "*** " .. player_name .. " left the game."
if timed_out then
announcement = announcement .. " (timed out)"
end
core.chat_send_all(announcement)
end
core.register_on_joinplayer(function(player)
local player_name = player:get_player_name()
player_list[player_name] = player
core.send_join_message(player_name)
end)
core.register_on_leaveplayer(function(player, timed_out)
local player_name = player:get_player_name()
player_list[player_name] = nil
core.send_leave_message(player_name, timed_out)
end)
function core.get_connected_players()
local temp_table = {}
for index, value in pairs(player_list) do
if value:is_player_connected() then
temp_table[#temp_table + 1] = value
end
end
return temp_table
end
function minetest.player_exists(name)
return minetest.get_auth_handler().get_auth(name) ~= nil
end
-- Returns two position vectors representing a box of `radius` in each
-- direction centered around the player corresponding to `player_name`
function core.get_player_radius_area(player_name, radius)
local player = core.get_player_by_name(player_name)
if player == nil then
return nil
end
local p1 = player:getpos()
local p2 = p1
if radius then
p1 = vector.subtract(p1, radius)
p2 = vector.add(p2, radius)
end
return p1, p2
end
function core.hash_node_position(pos)
return (pos.z+32768)*65536*65536 + (pos.y+32768)*65536 + pos.x+32768
end
function core.get_position_from_hash(hash)
local pos = {}
pos.x = (hash%65536) - 32768
hash = math.floor(hash/65536)
pos.y = (hash%65536) - 32768
hash = math.floor(hash/65536)
pos.z = (hash%65536) - 32768
return pos
end
function core.get_item_group(name, group)
if not core.registered_items[name] or not
core.registered_items[name].groups[group] then
return 0
end
return core.registered_items[name].groups[group]
end
function core.get_node_group(name, group)
core.log("deprecated", "Deprecated usage of get_node_group, use get_item_group instead")
return core.get_item_group(name, group)
end
function core.setting_get_pos(name)
local value = core.settings:get(name)
if not value then
return nil
end
return core.string_to_pos(value)
end
-- To be overriden by protection mods
function core.is_protected(pos, name)
return false
end
function core.record_protection_violation(pos, name)
for _, func in pairs(core.registered_on_protection_violation) do
func(pos, name)
end
end
-- Checks if specified volume intersects a protected volume
function core.intersects_protection(minp, maxp, player_name, interval)
-- 'interval' is the largest allowed interval for the 3D lattice of checks.
-- Compute the optimal float step 'd' for each axis so that all corners and
-- borders are checked. 'd' will be smaller or equal to 'interval'.
-- Subtracting 1e-4 ensures that the max co-ordinate will be reached by the
-- for loop (which might otherwise not be the case due to rounding errors).
-- Default to 4
interval = interval or 4
local d = {}
for _, c in pairs({"x", "y", "z"}) do
if maxp[c] > minp[c] then
d[c] = (maxp[c] - minp[c]) /
math.ceil((maxp[c] - minp[c]) / interval) - 1e-4
elseif maxp[c] == minp[c] then
d[c] = 1 -- Any value larger than 0 to avoid division by zero
else -- maxp[c] < minp[c], print error and treat as protection intersected
minetest.log("error", "maxp < minp in 'minetest.intersects_protection()'")
return true
end
end
for zf = minp.z, maxp.z, d.z do
local z = math.floor(zf + 0.5)
for yf = minp.y, maxp.y, d.y do
local y = math.floor(yf + 0.5)
for xf = minp.x, maxp.x, d.x do
local x = math.floor(xf + 0.5)
if core.is_protected({x = x, y = y, z = z}, player_name) then
return true
end
end
end
end
return false
end
local raillike_ids = {}
local raillike_cur_id = 0
function core.raillike_group(name)
local id = raillike_ids[name]
if not id then
raillike_cur_id = raillike_cur_id + 1
raillike_ids[name] = raillike_cur_id
id = raillike_cur_id
end
return id
end
-- HTTP callback interface
function core.http_add_fetch(httpenv)
httpenv.fetch = function(req, callback)
local handle = httpenv.fetch_async(req)
local function update_http_status()
local res = httpenv.fetch_async_get(handle)
if res.completed then
callback(res)
else
core.after(0, update_http_status)
end
end
core.after(0, update_http_status)
end
return httpenv
end
function core.close_formspec(player_name, formname)
return minetest.show_formspec(player_name, formname, "")
end
function core.cancel_shutdown_requests()
core.request_shutdown("", false, -1)
end