Avoid duplicate poi entries from the first section (#9235)

patches/server/0688-Optimise-general-POI-access.patch

@@ -32,10 +32,10 @@ had to be specifically modified.
 
 diff --git a/src/main/java/io/papermc/paper/util/PoiAccess.java b/src/main/java/io/papermc/paper/util/PoiAccess.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..05640f5f70e81833530e8098d30c400fed7ba6e1
+index 0000000000000000000000000000000000000000..69be1761b3b5ba7b496c1c10a4db897e6212d671
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/util/PoiAccess.java
-@@ -0,0 +1,800 @@
+@@ -0,0 +1,804 @@
 +package io.papermc.paper.util;
 +
 +import com.mojang.datafixers.util.Pair;
@@ -258,10 +258,12 @@ index 0000000000000000000000000000000000000000..05640f5f70e81833530e8098d30c400f
 +        final int centerX = sourcePosition.getX() >> 4;
 +        final int centerY = Mth.clamp(sourcePosition.getY() >> 4, lowerY, upperY);
 +        final int centerZ = sourcePosition.getZ() >> 4;
++        final long centerKey = CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ);
 +
 +        final LongArrayFIFOQueue queue = new LongArrayFIFOQueue();
-+        queue.enqueue(CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ));
 +        final LongOpenHashSet seen = new LongOpenHashSet();
++        seen.add(centerKey);
++        queue.enqueue(centerKey);
 +
 +        while (!queue.isEmpty()) {
 +            final long key = queue.dequeueLong();
@@ -315,7 +317,7 @@ index 0000000000000000000000000000000000000000..05640f5f70e81833530e8098d30c400f
 +                continue;
 +            }
 +
-+            final PoiSection poiSection = poiSectionOptional.orElse(null);
++            final PoiSection poiSection = poiSectionOptional.get();
 +
 +            final Map<Holder<PoiType>, Set<PoiRecord>> sectionData = poiSection.getData();
 +            if (sectionData.isEmpty()) {
@@ -499,10 +501,12 @@ index 0000000000000000000000000000000000000000..05640f5f70e81833530e8098d30c400f
 +        final int centerX = sourcePosition.getX() >> 4;
 +        final int centerY = Mth.clamp(sourcePosition.getY() >> 4, lowerY, upperY);
 +        final int centerZ = sourcePosition.getZ() >> 4;
++        final long centerKey = CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ);
 +
 +        final LongArrayFIFOQueue queue = new LongArrayFIFOQueue();
-+        queue.enqueue(CoordinateUtils.getChunkSectionKey(centerX, centerY, centerZ));
 +        final LongOpenHashSet seen = new LongOpenHashSet();
++        seen.add(centerKey);
++        queue.enqueue(centerKey);
 +
 +        while (!queue.isEmpty()) {
 +            final long key = queue.dequeueLong();
@@ -557,7 +561,7 @@ index 0000000000000000000000000000000000000000..05640f5f70e81833530e8098d30c400f
 +                continue;
 +            }
 +
-+            final PoiSection poiSection = poiSectionOptional.orElse(null);
++            final PoiSection poiSection = poiSectionOptional.get();
 +
 +            final Map<Holder<PoiType>, Set<PoiRecord>> sectionData = poiSection.getData();
 +            if (sectionData.isEmpty()) {