Fixes incorrect spigot handling of the invulnerability damage
reduction applied when an already invulnerable entity is damaged with a
larger damage amount than the initial damage.
Vanilla still damages entities even if invulnerable if the damage to be
applied is larger than the previous damage taken. In that case, vanilla
applies the difference between the previous damage taken and the
proposed damage.
Spigot's damage modifier API takes over the computation of damage
reducing effects, however spigot invokes this handling with the initial
damage before computing the difference to the previous damage amount.
This leads to the reduction values to generally be larger than expected,
as they are computed on the not-yet-reduced value.
Spigot applies these reductions after calling the EntityDamageEvent and
*then* subtracts the previous damage point, leading to the final damage
amount being smaller than expected.
This patch cannot simply call the EntityDamageEvent with the reduced
damage, as that would lead to EntityDamageEvent#getDamage() returning
the already reduced damage, which breaks its method contract.
Instead, this patch makes use of the DamageModifier API, implementing
the last-damage-reduction as a DamageModifier.
Spigot uses a no longer valid ClientboundContainerSetSlotPacket with the
slot -1, which would update the carried stack in versions <=1.21.1 but
now leads to an IOOB.
1.21.2 instead introduced the ClientboundSetCursorItemPacket, which this
patch uses instead.
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.
The recent upstream update moved around the event logic for
EntiyDamageEvent and its derivatives.
However, the event was called on every call to #hurt as it was moved out
of actuallyHurt.
This patch moves the invocation directly before the #actuallyHurt calls,
respective invulnerable timings.
Spigot incorrectly instanceOf checks the EntityTargetEvent#getTarget
against the internal ItemEntity type and removes the nearest wanted item
memory if said instanceOf check fails, (which is always the case)
causing allays to behave differently as they constantly lose their
target item.
This commit fixes the faulty behaviour by instance performing a check
against the CraftItem type.
The EntityResurrectEvent logic is supposed to locate a totem of undying
in any of the interaction slots of the player inventory and then, if the
called EntityResurrectEvent is not cancelled, shrink that item by 1,
usually reducing it to zero.
For this, the logic iterates over the items in the interaction slots and
breaks out the loop if a totem of undying was found.
However, even if no totem of undying was found, the iteration item stack
variable remains as a refernce to the last interaction slot probed.
Plugins uncancelling a EntityResurrectEvent, which is published
pre-cancelled to listeners if no totem of undying could be found,
would hence cause the server logic to shrink completely unrelated items
found in, at the writing of this patch, the players off hand slot.
This patch corrects this behaviour by only shrinking the item if a totem
of undying was found and the event was called uncancelled.
Prior to this commit, the tropical fish bucket meta would set the body
color to the previous metas pattern colour when updating the pattern
colour.
This commit hence simply fixes this by using the proper body colour
value when updating the pattern color.
Bjarne Koll