Normally the JVM can inline virtual getters by having two sets of code, one is the 'optimized' code and the other is the 'deoptimized' code.
If a single type is used 99% of the time, then its worth it to inline, and to revert to 'deoptimized' the 1% of the time we encounter other types.
But if two types are encountered commonly, then the JVM can't inline them both, and the call overhead remains.
This scenario also occurs with BlockPos and MutableBlockPos.
The variables in BlockPos are final, so MutableBlockPos can't modify them.
MutableBlockPos fixes this by adding custom mutable variables, and overriding the getters to access them.
This approach with utility methods that operate on MutableBlockPos and BlockPos.
Specific examples are BlockPosition.up(), and World.isValidLocation().
It makes these simple methods much slower than they need to be.
This should result in an across the board speedup in anything that accesses blocks or does logic with positions.
This is based upon conclusions drawn from inspecting the assenmbly generated bythe JIT compiler on my microbenchmarks.
They had 'callq' (invoke) instead of 'mov' (get from memory) instructions.
API relating to items being actively used by a LivingEntity
such as a bow or eating food.
== AT ==
public net/minecraft/world/entity/LivingEntity completeUsingItem()V
public net/minecraft/server/level/ServerPlayer completeUsingItem()V
Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>
Called when a player is firing a bow and the server is choosing an arrow to use.
Plugins can skip selection of certain arrows and control which is used.
People are able to abuse the way Bukkit handles teleportation across worlds since it provides a built in teleportation safety check.
To abuse the safety check, players are required to get into a location deemed unsafe by Bukkit e.g. be within a chest or door block. While they are in this block, they accept a teleport request from a player within a different world. Once the player teleports, Minecraft will recursively search upwards for a safe location, this could eventually land within a player's skybase.
Example setup to perform the glitch: http://puu.sh/ng3PC/cf072dcbdb.png
The wanted destination was on top of the emerald block however the player ended on top of the diamond block. This only is the case if the player is teleporting between worlds.
Techcable
