Shiroha/shiroha-server/minecraft-patches/features/0076-Gale-Optimize-random-calls-in-chunk-ticking.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: MrHua269 <mrhua269@gmail.com>
Date: Thu, 4 Jun 2026 17:15:00 +0800
Subject: [PATCH] Gale: Optimize random calls in chunk ticking

License: GPL-3.0-only (https://www.gnu.org/licenses/gpl-3.0.html)
Gale - https://github.com/GaleMC/Gale

This patch is based on the following patch:
"Optimize random calls in chunk ticking"
By: Paul Sauve <paul@technove.co>
As part of: Airplane (https://github.com/TECHNOVE/Airplane)
Licensed under: GPL-3.0-only (https://www.gnu.org/licenses/gpl-3.0.html)

The patch also received the following subsequent modification:
By: Kevin Raneri <kevin.raneri@gmail.com>
As part of: Pufferfish (https://github.com/pufferfish-gg/Pufferfish)
Licensed under: GPL-3.0-only (https://www.gnu.org/licenses/gpl-3.0.html)

* Description *

Throttling of ice and snow tick has been moved to another patch as
configurable ice and snow tick chance.

* Airplane description *

Especially at over 30,000 chunks these random calls are fairly heavy. We
use a different method here for checking lightning, and for checking
ice.

Lightning: Each chunk now keeps an int of how many ticks until the
lightning should strike. This int is a random number from 0 to 100000 * 2,
the multiplication is required to keep the probability the same.

Ice and snow: We just generate a single random number 0-16 and increment
it, while checking if it's 0 for the current chunk.

Depending on configuration for things that tick in a chunk, this is a
5-10% improvement.

* Airplane copyright *

Airplane
Copyright (C) 2020 Technove LLC

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.

diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
index f95b0efc2f61a12eeb42c1a867ccdf87cb51a1a2..c79193fa5a12186d5f1ecb25abf92e2cb4a04f8d 100644
--- a/net/minecraft/server/level/ServerLevel.java
+++ b/net/minecraft/server/level/ServerLevel.java
@@ -1054,7 +1054,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
     }
 
     // Paper start - optimise random ticking
-    private final io.papermc.paper.threadedregions.util.SimpleThreadLocalRandomSource simpleRandom = io.papermc.paper.threadedregions.util.SimpleThreadLocalRandomSource.INSTANCE; // Folia - region threading
+    public final io.papermc.paper.threadedregions.util.SimpleThreadLocalRandomSource simpleRandom = io.papermc.paper.threadedregions.util.SimpleThreadLocalRandomSource.INSTANCE; // Folia - region threading // Shiroha - Make public for : Gale: Optimize random calls in chunk ticking
 
     private void optimiseRandomTick(final LevelChunk chunk, final int tickSpeed) {
         final LevelChunkSection[] sections = chunk.getSections();
@@ -1136,7 +1136,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
         int minZ = chunkPos.getMinBlockZ();
         ProfilerFiller profiler = Profiler.get();
         profiler.push("thunder");
-        if (!this.paperConfig().environment.disableThunder && raining && this.isThundering() && this.spigotConfig.thunderChance > 0 && this.random.nextInt(this.spigotConfig.thunderChance) == 0) { // Spigot // Paper - Option to disable thunder
+        if (!this.paperConfig().environment.disableThunder && raining && this.isThundering() && this.spigotConfig.thunderChance > 0 /*&& this.random.nextInt(this.spigotConfig.thunderChance) == 0*/ && chunk.shouldDoLightning(this.random)) { // Spigot // Paper - Option to disable thunder // Gale - Airplane - optimize random calls in chunk ticking - replace random with shouldDoLightning
             BlockPos pos = this.findLightningTargetAround(this.getBlockRandomPos(minX, 0, minZ, 15));
             if (this.isRainingAt(pos)) {
                 DifficultyInstance difficulty = this.getCurrentDifficultyAt(pos);
diff --git a/net/minecraft/world/level/chunk/LevelChunk.java b/net/minecraft/world/level/chunk/LevelChunk.java
index df6d65c258ea48e4e3b2f4ec02150ab06cd6682f..59fa80b96e79842fc74c3b8ce0f9d8cb3cb49054 100644
--- a/net/minecraft/world/level/chunk/LevelChunk.java
+++ b/net/minecraft/world/level/chunk/LevelChunk.java
@@ -144,6 +144,19 @@ public class LevelChunk extends ChunkAccess implements DebugValueSource, ca.spot
     }
     // Paper end - get block chunk optimisation
 
+    // Gale start - Airplane - optimize random calls in chunk ticking - instead of using a random every time the chunk is ticked, define when lightning strikes preemptively
+    private int lightningTick;
+    // shouldDoLightning compiles down to 29 bytes, which with the default of 35 byte inlining should guarantee an inline
+    public final boolean shouldDoLightning(net.minecraft.util.RandomSource random) {
+        if (this.lightningTick-- <= 0) {
+            this.lightningTick = random.nextInt(this.level.spigotConfig.thunderChance) << 1;
+            return true;
+        }
+        return false;
+    }
+    // Gale end - Airplane - optimize random calls in chunk ticking - instead of using a random every time the chunk is ticked, define when lightning strikes preemptively
+
+
     public LevelChunk(final Level level, final ChunkPos pos) {
         this(level, pos, UpgradeData.EMPTY, new LevelChunkTicks<>(), new LevelChunkTicks<>(), 0L, null, null, null);
     }
@@ -180,6 +193,8 @@ public class LevelChunk extends ChunkAccess implements DebugValueSource, ca.spot
         this.debug = !empty && this.level.isDebug();
         this.defaultBlockState = empty ? VOID_AIR_BLOCKSTATE : AIR_BLOCKSTATE;
         // Paper end - get block chunk optimisation
+
+        this.lightningTick = io.papermc.paper.threadedregions.util.SimpleThreadLocalRandomSource.INSTANCE.nextInt(100000) << 1; // Gale - Airplane - optimize random calls in chunk ticking - initialize lightning tick
     }
 
     public LevelChunk(final ServerLevel level, final ProtoChunk protoChunk, final LevelChunk.@Nullable PostLoadProcessor postLoad) {