Spigot still maintains some partial implementation of "tick skipping", a
practice in which the MinecraftServer.currentTick field is updated not
by an increment of one per actual tick, but instead set to
System.currentTimeMillis() / 50. This behaviour means that the tracked
tick may "skip" a tick value in case a previous tick took more than the
expected 50ms.
To compensate for this in important paths, spigot/craftbukkit
implements "wall-time". Instead of incrementing/decrementing ticks on
block entities/entities by one for each call to their tick() method,
they instead increment/decrement important values, like
an ItemEntity's age or pickupDelay, by the difference of
`currentTick - lastTick`, where `lastTick` is the value of
`currentTick` during the last tick() call.
These "fixes" however do not play nicely with minecraft's simulation
distance as entities/block entities implementing the above behaviour
would "catch up" their values when moving from a non-ticking chunk to a
ticking one as their `lastTick` value remains stuck on the last tick in
a ticking chunk and hence lead to a large "catch up" once ticked again.
Paper completely removes the "tick skipping" behaviour (See patch
"Further-improve-server-tick-loop"), making the above precautions
completely unnecessary, which also rids paper of the previous described
incompatibility with non-ticking chunks.
Most of the visual artifacts that result from having item merge radius above vanilla levels is from items merging vertically,
which realistically, only happens when a player is dropping items, or items are dropping from breaking a block.
Most of the scenarios where item merging makes sense involves the two item entities being on the same Y level. i.e on the ground next to each other.
This is even more apparent since paper fixed items being able to merge through blocks.
This patch allows us to configure items to only merge horizontally, which is what vanilla does.
This allows us to have both the reduced number of item entities a high item-merge radius provides,
without most of the visual artifacts caused by items merging vertically.
Paper makes the entity random thread-safe
and constructing an entity off the main thread
should be supported. Some entities (for whatever
reason) use the level's random in some places.
- add auto expire setting
- add setter for block data
- add accessors for block state
== AT ==
public net.minecraft.world.entity.item.FallingBlockEntity blockState
Co-authored-by: Lukas Planz <lukas.planz@web.de>
Item entities only have their gravity ticked every 4 ticks when on ground.
Fix that and also remove Spigot's arbitrary tick skipping. It's a terribly
cheap way of getting extra performance that doesn't really work at all.
This gives a per-world control on how much TNT will be processed per-tick,
preventing a massive TNT detonation from lagging out the server.
By: Aikar <aikar@aikar.co>
This feature gives 3 new configurable ranges that if an entity of the matching type is outside of this radius of any player, will tick at 5% of its normal rate.
This will drastically cut down on tick timings for entities that are not in range of a user to actually be "used".
This change can have dramatic impact on gameplay if configured too low. Balance according to your servers desired gameplay.
By: Aikar <aikar@aikar.co>
This allows the merging of Experience orbs, as well as the configuration of the merge radius of items. Additionally it refactors the merge algorithm to be a better experience for players.
By: md_5 <git@md-5.net>
