The problem was pointed out by Josh
(gitlab.com/krazy-j) in merge request !22.
Apparently MT is not very smart about marking
mapblocks dirty to send to clients based on
calling mt.set_node(), i.e. it will mark them
dirty presumptively even if you set the node to
the same value it had already been.
This behavior can be confirmed by registering
an ABM against a common node like grass and
setting action = minetest.set_node. This
causes every mapblock containing that node
to be invalidated every interval, causing a big
spike in the packets received each interval
that you can clearly see on the F5 graph.
Rather than just fixing it for the most easily
observed case (fire checks), add utlity functions
to check this for ALL node change situations,
and apply it more or less universally anywhere
that we are not certain that the node is being
changed and we don't need to worry about the
extra overhead cost of the check.
Note that we don't need a
nodecore.set_loud_check call, as set_loud was
only ever being used already in cases where
we were pretty sure we were actually changing
a node.
- New near_unloaded API that supports custom
distance parameter, map bounds check, and
some optimizations.
- Add area automatic unload check support to ABM
API and add to applicable ABMs, replacing many
old manual checks.
Note that the explicit unload check is only strictly
necessary when something will happen due to
a node NOT being present in the area, e.g. something
igniting due to absent coolant, or soaking quantity
being reset due to missing sources. In simple cases
where the absence of a thing causes the ABM to do
nothing, then the standard check can work because
the default action is to do nothing anyway.
Witness checks include data about the node in
place at the time that the witness even occurred,
so players are not awarded credit if the node they
see there was changed again afterwards. A lot of
old witness code inserted the witness right
before the node was changed, since the node
change was done as a tail call, but this does not
work with delayed witnessing because the
delayed witness data would be tied to the old
node, not the replacement one.
Moving witness to after node setting should fix
a number of broken hints that should have been
delayed-witnessable, e.g. brick bonding.
- Make planted eggcorns evident via visual and
description; it was too easy for new players to
think they screwed up the recipe.
- Leaves inherit growth rate of trunk.
- Growth particles at tip of growing trunk.
- Code cleanup, refactoring, break up large files.
- Minor texture adjustments.