Rewrite chunk system (#8177)

Patch documentation to come

Issues with the old system that are fixed now:
- World generation does not scale with cpu cores effectively.
- Relies on the main thread for scheduling and maintaining chunk state, dropping chunk load/generate rates at lower tps.
- Unreliable prioritisation of chunk gen/load calls that block the main thread.
- Shutdown logic is utterly unreliable, as it has to wait for all chunks to unload - is it guaranteed that the chunk system is in a state on shutdown that it can reliably do this? Watchdog shutdown also typically failed due to thread checks, which is now resolved.
- Saving of data is not unified (i.e can save chunk data without saving entity data, poses problems for desync if shutdown is really abnormal.
- Entities are not loaded with chunks. This caused quite a bit of headache for Chunk#getEntities API, but now the new chunk system loads entities with chunks so that they are ready whenever the chunk loads in. Effectively brings the behavior back to 1.16 era, but still storing entities in their own separate regionfiles.

The above list is not complete. The patch documentation will complete it.

New chunk system hard relies on starlight and dataconverter, and most importantly the new concurrent utilities in ConcurrentUtil.

Some of the old async chunk i/o interface (i.e the old file io thread reroutes _some_ calls to the new file io thread) is kept for plugin compat reasons. It will be removed in the next major version of minecraft.

The old legacy chunk system patches have been moved to the removed folder in case we need them again.

1 files changed, 24 insertions, 0 deletions

diff --git a/patches/server/0212-Expand-Explosions-API.patch b/patches/server/0212-Expand-Explosions-API.patch
new file mode 100644
index 0000000000..f503a30fbc
--- /dev/null
+++ b/patches/server/0212-Expand-Explosions-API.patch
@@ -0,0 +1,24 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <[email protected]>
+Date: Wed, 20 Jun 2018 23:17:24 -0400
+Subject: [PATCH] Expand Explosions API
+
+Add Entity as a Source capability, and add more API choices, and on Location.
+
+diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+index fee71f001933f9320daa865db433f3b5855278fa..339baff7014e98cbe03806d9a689ec09e0b30a47 100644
+--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
++++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+@@ -703,6 +703,12 @@ public class CraftWorld extends CraftRegionAccessor implements World {
+     public boolean createExplosion(double x, double y, double z, float power, boolean setFire, boolean breakBlocks, Entity source) {
+         return !this.world.explode(source == null ? null : ((CraftEntity) source).getHandle(), x, y, z, power, setFire, breakBlocks ? Explosion.BlockInteraction.BREAK : Explosion.BlockInteraction.NONE).wasCanceled;
+     }
++    // Paper start
++    @Override
++    public boolean createExplosion(Entity source, Location loc, float power, boolean setFire, boolean breakBlocks) {
++        return !world.explode(source != null ? ((org.bukkit.craftbukkit.entity.CraftEntity) source).getHandle() : null, loc.getX(), loc.getY(), loc.getZ(), power, setFire, breakBlocks ? Explosion.BlockInteraction.BREAK : Explosion.BlockInteraction.NONE).wasCanceled;
++    }
++    // Paper end
+ 
+     @Override
+     public boolean createExplosion(Location loc, float power) {