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.
This gets rid of the 5.4+ "deprecated get_player_velocity" warning
and modernizes the code to use get_velocity() everywhere, while
still remaining compatible with 5.3 for now (tested). The polyfill
had to be on joinplayer because the nc_player_pickup auto-one-time
method of using after() won't reliably patch the player before some
other globalstep tries to read player velocity.
When MT 5.5 is released and 5.3 support ends, the polyfill just
needs to be removed to clean it up.
Also tidied up and consistentized the logging for other hooks.
Lock more things behind prerequisite hints, even if
they're not absolutely strictly necessary to complete
in that order, if they would commonly be done in
that order. This reduces players being overwhelmed
by available hints very early in the game, and avoids
red herrings like "find lux" which can technically be
accomplished but yields no useful results until the
player can act on them.
Any liquids that are dropped should become
placed nodes. It was observed before this that
wet concrete may have been displaced in such
a way that it created a stack node; this ensures
such things are precluded as much as possible.
These cause some issues, like the ability to soak
dirt under water for a short time to initialize the
soaking metadata, then remove the water flow,
then add it in and have leaching complete instantly
because the neighbor check prevented the soaking
ABM from firing to detect that the water was
removed.
In the course of investigating why ABMs are so slow
to begin with, it was discovered that having neighbor
checks can slow an ABM down by a factor of something
like 7x, so clearly the assumption that the neigbor check
being done in C++ as "efficient" was false. This means
that we may be better off just always firing the ABM and
letting Lua check only a couple of relevant nodes (e.g.
for water flows in the space above) instead for
performance.
The main performance concern was dirt leaching, since
dirt generates naturally in the world in bulk, but if the
single check for water above may be faster than checking
all 26 neighbors in C++ anyway, we might as well let the
soaking API run for it so that it can detect the water having
been removed and reset the counters.
- For inventory and wield images, this is already
possible via override.txt since 5.3.
- For special tiles, this will be possible in 5.4.
- This complicates things, and introduces warning
messages into mods built without awareness of
this feaure.
- As far as I know, no texture packs have actually
ever used this feature.
For one thing, it's a bit overpowered when you go
right from infused still digging lode ore as loose
cobble, right to boosted-infused digging it as raw
ore.
For another, uncobbled lux stone is purposefully
labeled as just plain stone to force the player to
pay attention to light cues, but this would make
inventory management problematic once smooth
lux stone has been collected with boosted tools.
Tables containing lists of items to register AISMs
for are broken out into indexes at the time of
registration, so if we delay building the lists, we
need to delay registering the AISMs. Luckily
AISMs can be registered later at runtime.
- Split infusion logic from tool registration
so tools aren't depending on sharing local
tables with infusion logic.
- Use alternative_lux_* fields on tool item
registrations to control how lux infusion and
boost/unboost applies to tools.
- It should now be possible to register tools
independently that can tap into lux infusion
and boost features.
- It should now be possible to make tools
boostable, unboostable, and infusable all
independently, so they don't need to support
all those actions, and they don't need to
round-trip from e.g. a boost/unboost operation.
- We no longer depend on a naming convention
for boost/unboost pairs (though in practice we
follow it in the core game, but mods are not
required to).
When I was watching other people work on their
reactors, I was standing some distance off and
still got significant radiation damage after a
short time, even with the reactors subcritical.
Cut the radiation accumulation rate by 75% this
time, while buffing flux a little more relative to
solids.
Items in inventory can both emit radiation
and shield you from in-inventory radiation.
This process happens separately from
node-space radiation, though.
Hints themselves have not been tided up
much, but this makes the project of fixing the
hints for each mod a little more manageable
and breaks up the hard-to-navigate single
monolithic hints file in the old guide mod.
The old guide mod has now been completely
retired. Hints are now a full-fledged API-layer
standard feature.
