PaperMC/patches/server/0043-Optimize-explosions.patch
Bjarne Koll c5a10665b8
Remove wall-time / unused skip tick protection (#11412)
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.
2024-09-19 16:36:07 +02:00

133 lines
6.2 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Byteflux <byte@byteflux.net>
Date: Wed, 2 Mar 2016 11:59:48 -0600
Subject: [PATCH] Optimize explosions
The process of determining an entity's exposure from explosions can be
expensive when there are hundreds or more entities in range.
This patch adds a per-tick cache that is used for storing and retrieving
an entity's exposure during an explosion.
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 2f57739431eb695149019724e2923f0d02e88d07..1ba2b1aaf0936963aca73a43632f978c95bf95e6 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1571,6 +1571,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
this.profiler.pop();
this.profiler.pop();
+ worldserver.explosionDensityCache.clear(); // Paper - Optimize explosions
}
this.profiler.popPush("connection");
diff --git a/src/main/java/net/minecraft/world/level/Explosion.java b/src/main/java/net/minecraft/world/level/Explosion.java
index 35d541c549cb07508e68388b18f38a4ffd788176..23a0a8d9beb7ca400134fb6a65b3133baceeed83 100644
--- a/src/main/java/net/minecraft/world/level/Explosion.java
+++ b/src/main/java/net/minecraft/world/level/Explosion.java
@@ -279,7 +279,7 @@ public class Explosion {
// CraftBukkit end
}
- double d12 = (1.0D - d7) * (double) Explosion.getSeenPercent(vec3d, entity) * (double) this.damageCalculator.getKnockbackMultiplier(entity);
+ double d12 = (1.0D - d7) * this.getBlockDensity(vec3d, entity) * (double) this.damageCalculator.getKnockbackMultiplier(entity); // Paper - Optimize explosions
double d13;
if (entity instanceof LivingEntity) {
@@ -536,4 +536,84 @@ public class Explosion {
private BlockInteraction() {}
}
+ // Paper start - Optimize explosions
+ private float getBlockDensity(Vec3 vec3d, Entity entity) {
+ if (!this.level.paperConfig().environment.optimizeExplosions) {
+ return getSeenPercent(vec3d, entity);
+ }
+ CacheKey key = new CacheKey(this, entity.getBoundingBox());
+ Float blockDensity = this.level.explosionDensityCache.get(key);
+ if (blockDensity == null) {
+ blockDensity = getSeenPercent(vec3d, entity);
+ this.level.explosionDensityCache.put(key, blockDensity);
+ }
+
+ return blockDensity;
+ }
+
+ static class CacheKey {
+ private final Level world;
+ private final double posX, posY, posZ;
+ private final double minX, minY, minZ;
+ private final double maxX, maxY, maxZ;
+
+ public CacheKey(Explosion explosion, AABB aabb) {
+ this.world = explosion.level;
+ this.posX = explosion.x;
+ this.posY = explosion.y;
+ this.posZ = explosion.z;
+ this.minX = aabb.minX;
+ this.minY = aabb.minY;
+ this.minZ = aabb.minZ;
+ this.maxX = aabb.maxX;
+ this.maxY = aabb.maxY;
+ this.maxZ = aabb.maxZ;
+ }
+
+ @Override
+ public boolean equals(Object o) {
+ if (this == o) return true;
+ if (o == null || getClass() != o.getClass()) return false;
+
+ CacheKey cacheKey = (CacheKey) o;
+
+ if (Double.compare(cacheKey.posX, posX) != 0) return false;
+ if (Double.compare(cacheKey.posY, posY) != 0) return false;
+ if (Double.compare(cacheKey.posZ, posZ) != 0) return false;
+ if (Double.compare(cacheKey.minX, minX) != 0) return false;
+ if (Double.compare(cacheKey.minY, minY) != 0) return false;
+ if (Double.compare(cacheKey.minZ, minZ) != 0) return false;
+ if (Double.compare(cacheKey.maxX, maxX) != 0) return false;
+ if (Double.compare(cacheKey.maxY, maxY) != 0) return false;
+ if (Double.compare(cacheKey.maxZ, maxZ) != 0) return false;
+ return world.equals(cacheKey.world);
+ }
+
+ @Override
+ public int hashCode() {
+ int result;
+ long temp;
+ result = world.hashCode();
+ temp = Double.doubleToLongBits(posX);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(posY);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(posZ);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(minX);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(minY);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(minZ);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(maxX);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(maxY);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ temp = Double.doubleToLongBits(maxZ);
+ result = 31 * result + (int) (temp ^ (temp >>> 32));
+ return result;
+ }
+ }
+ // Paper end
}
diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index e8b8475dd6fd7b89651f744da2cb9696c73ddc3e..a272aaff11ac077853c06f729a5d8b09f866e0f8 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -168,6 +168,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
private org.spigotmc.TickLimiter entityLimiter;
private org.spigotmc.TickLimiter tileLimiter;
private int tileTickPosition;
+ public final Map<Explosion.CacheKey, Float> explosionDensityCache = new HashMap<>(); // Paper - Optimize explosions
public CraftWorld getWorld() {
return this.world;