Shiroha/shiroha-server/minecraft-patches/features/0031-Reduce-allocation-in-PoiAccess.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: NanaChiyo0721 <nanachiyo0721@163.com>
Date: Wed, 5 Aug 2026 23:53:48 +0800
Subject: [PATCH] Reduce allocation in PoiAccess


diff --git a/ca/spottedleaf/moonrise/patches/poi_lookup/PoiAccess.java b/ca/spottedleaf/moonrise/patches/poi_lookup/PoiAccess.java
index 85d80b3952a76b0ca7f67401a659cf35dd55b082..d4f95458d2e35aedb0fd5230fcd74b968437d8a5 100644
--- a/ca/spottedleaf/moonrise/patches/poi_lookup/PoiAccess.java
+++ b/ca/spottedleaf/moonrise/patches/poi_lookup/PoiAccess.java
@@ -89,6 +89,23 @@ public final class PoiAccess {
         return (centerDiffX * centerDiffX) + (centerDiffY * centerDiffY) + (centerDiffZ * centerDiffZ);
     }
 
+    // Shiroha start- Reduce allocation in PoiAccess
+    private static int getSectionIndex(
+            final int x,
+            final int y,
+            final int z,
+            final int lowerX,
+            final int lowerY,
+            final int lowerZ,
+            final int spanY,
+            final int spanZ
+    ) {
+        return (x - lowerX) * spanY * spanZ
+                + (y - lowerY) * spanZ
+                + (z - lowerZ);
+    }
+    // Shiroha end - Reduce allocation in PoiAccess
+
     public static void findClosestPoiDataRecords(final PoiManager poiStorage,
                                                  final Predicate<Holder<PoiType>> villagePlaceType,
                                                  // position predicate must not modify chunk POI
@@ -116,9 +133,15 @@ public final class PoiAccess {
         final int centerZ = sourcePosition.getZ() >> 4;
         final long centerKey = CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ);
 
+        // Shiroha start - Reduce allocation in PoiAccess
+        final int spanX = upperX - lowerX + 1;
+        final int spanY = upperY - lowerY + 1;
+        final int spanZ = upperZ - lowerZ + 1;
+        // Shiroha end - Reduce allocation in PoiAccess
+
         final LongArrayFIFOQueue queue = new LongArrayFIFOQueue();
-        final LongOpenHashSet seen = new LongOpenHashSet();
-        seen.add(centerKey);
+        final java.util.BitSet seen = new java.util.BitSet(spanX * spanY * spanZ); // Shiroha - Reduce allocation in PoiAccess
+        seen.set(getSectionIndex(centerX, centerY, centerZ, lowerX, lowerY, lowerZ, spanY, spanZ)); // Shiroha - Reduce allocation in PoiAccess
         queue.enqueue(centerKey);
 
         while (!queue.isEmpty()) {
@@ -159,8 +182,18 @@ public final class PoiAccess {
                         final int neighbourY = sectionY + dy;
                         final int neighbourZ = sectionZ + dz;
 
+                        // Shiroha start - Reduce allocation in PoiAccess
+                        if (neighbourX < lowerX || neighbourX > upperX
+                                || neighbourY < lowerY || neighbourY > upperY
+                                || neighbourZ < lowerZ || neighbourZ > upperZ) {
+                            continue;
+                        }
+
+                        final int neighbourIndex = getSectionIndex(neighbourX, neighbourY, neighbourZ, lowerX, lowerY, lowerZ, spanY, spanZ);
+                        // Shiroha end - Reduce allocation in PoiAccess
                         final long neighbourKey = CoordinateUtils.getChunkSectionKey(neighbourX, neighbourY, neighbourZ);
-                        if (seen.add(neighbourKey)) {
+                        if (!seen.get(neighbourIndex)) { // Shiroha - Reduce allocation in PoiAccess
+                            seen.set(neighbourIndex); // Shiroha - Reduce allocation in PoiAccess
                             queue.enqueue(neighbourKey);
                         }
                     }
@@ -359,9 +392,15 @@ public final class PoiAccess {
         final int centerZ = sourcePosition.getZ() >> 4;
         final long centerKey = CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ);
 
+        // Shiroha start - Reduce allocation in PoiAccess
+        final int spanX = upperX - lowerX + 1;
+        final int spanY = upperY - lowerY + 1;
+        final int spanZ = upperZ - lowerZ + 1;
+        // Shiroha end - Reduce allocation in PoiAccess
+
         final LongArrayFIFOQueue queue = new LongArrayFIFOQueue();
-        final LongOpenHashSet seen = new LongOpenHashSet();
-        seen.add(centerKey);
+        final java.util.BitSet seen = new java.util.BitSet(spanX * spanY * spanZ); // Shiroha - Reduce allocation in PoiAccess
+        seen.set(getSectionIndex(centerX, centerY, centerZ, lowerX, lowerY, lowerZ, spanY, spanZ)); // Shiroha - Reduce allocation in PoiAccess
         queue.enqueue(centerKey);
 
         while (!queue.isEmpty()) {
@@ -403,8 +442,18 @@ public final class PoiAccess {
                         final int neighbourY = sectionY + dy;
                         final int neighbourZ = sectionZ + dz;
 
+                        // Shiroha start - Reduce allocation in PoiAccess
+                        if (neighbourX < lowerX || neighbourX > upperX
+                                || neighbourY < lowerY || neighbourY > upperY
+                                || neighbourZ < lowerZ || neighbourZ > upperZ) {
+                            continue;
+                        }
+
+                        final int neighbourIndex = getSectionIndex(neighbourX, neighbourY, neighbourZ, lowerX, lowerY, lowerZ, spanY, spanZ);
+                        // Shiroha end - Reduce allocation in PoiAccess
                         final long neighbourKey = CoordinateUtils.getChunkSectionKey(neighbourX, neighbourY, neighbourZ);
-                        if (seen.add(neighbourKey)) {
+                        if (!seen.get(neighbourIndex)) { // Shiroha - Reduce allocation in PoiAccess
+                            seen.set(neighbourIndex); // Shiroha - Reduce allocation in PoiAccess
                             queue.enqueue(neighbourKey);
                         }
                     }