58 lines
3.2 KiB
Markdown
58 lines
3.2 KiB
Markdown
|
|
|
|
administrative world anchor
|
|
---------------------------
|
|
|
|
A world anchor is an object in the Minetest world that causes the server
|
|
to keep surrounding parts of the world running even when no players
|
|
are nearby. It is mainly used to allow machines to run unattended:
|
|
normally machines are suspended when not near a player. The technic
|
|
mod supplies a form of world anchor, as a placable block, but it is not
|
|
straightforwardly available to players. There is no recipe for it, so it
|
|
is only available if explicitly spawned into existence by someone with
|
|
administrative privileges. In a single-player world, the single player
|
|
normally has administrative privileges, and can obtain a world anchor
|
|
by entering the chat command "/give singleplayer technic:admin\_anchor".
|
|
|
|
The world anchor tries to force a cubical area, centered upon the anchor,
|
|
to stay loaded. The distance from the anchor to the most distant map
|
|
nodes that it will keep loaded is referred to as the "radius", and can be
|
|
set in the world anchor's interaction form. The radius can be set as low
|
|
as 0, meaning that the anchor only tries to keep itself loaded, or as high
|
|
as 255, meaning that it will operate on a 511×511×511 cube.
|
|
Larger radii are forbidden, to avoid typos causing the server excessive
|
|
work; to keep a larger area loaded, use multiple anchors. Also use
|
|
multiple anchors if the area to be kept loaded is not well approximated
|
|
by a cube.
|
|
|
|
The world is always kept loaded in units of 16×16×16 cubes,
|
|
confusingly known as "map blocks". The anchor's configured radius takes
|
|
no account of map block boundaries, but the anchor's effect is actually to
|
|
keep loaded each map block that contains any part of the configured cube.
|
|
The anchor's interaction form includes a status note showing how many map
|
|
blocks this is, and how many of those it is successfully keeping loaded.
|
|
When the anchor is disabled, as it is upon placement, it will always
|
|
show that it is keeping no map blocks loaded; this does not indicate
|
|
any kind of failure.
|
|
|
|
The world anchor can optionally be locked. When it is locked, only
|
|
the anchor's owner, the player who placed it, can reconfigure it or
|
|
remove it. Only the owner can lock it. Locking an anchor is useful
|
|
if the use of anchors is being tightly controlled by administrators:
|
|
an administrator can set up a locked anchor and be sure that it will
|
|
not be set by ordinary players to an unapproved configuration.
|
|
|
|
The server limits the ability of world anchors to keep parts of the world
|
|
loaded, to avoid overloading the server. The total number of map blocks
|
|
that can be kept loaded in this way is set by the server configuration
|
|
item "max\_forceloaded\_blocks" (in minetest.conf), which defaults to
|
|
only 16. For comparison, each player normally keeps 125 map blocks loaded
|
|
(a radius of 32). If an enabled world anchor shows that it is failing to
|
|
keep all the map blocks loaded that it would like to, this can be fixed
|
|
by increasing max\_forceloaded\_blocks by the amount of the shortfall.
|
|
|
|
The tight limit on force-loading is the reason why the world anchor is
|
|
not directly available to players. With the limit so low both by default
|
|
and in common practice, the only feasible way to determine where world
|
|
anchors should be used is for administrators to decide it directly.
|