From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: CullanP <cullanpage@gmail.com>
Date: Thu, 3 Mar 2016 02:13:38 -0600
Subject: [PATCH] Avoid hopper searches if there are no items

Hoppers searching for items and minecarts is the most expensive part of hopper ticking.
We keep track of the number of minecarts and items in a chunk.
If there are no items in the chunk, we skip searching for items.
If there are no minecarts in the chunk, we skip searching for them.

Usually hoppers aren't near items, so we can skip most item searches.
And since minecart hoppers are used _very_ rarely near we can avoid alot of searching there.

Combined, this adds up a lot.

diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -0,0 +0,0 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
                 }
             }
 
-        });
+        }, predicate == net.minecraft.world.entity.EntitySelector.CONTAINER_ENTITY_SELECTOR); // Paper
         return list;
     }
 
diff --git a/src/main/java/net/minecraft/world/level/entity/EntitySection.java b/src/main/java/net/minecraft/world/level/entity/EntitySection.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/world/level/entity/EntitySection.java
+++ b/src/main/java/net/minecraft/world/level/entity/EntitySection.java
@@ -0,0 +0,0 @@ public class EntitySection<T> {
     protected static final Logger LOGGER = LogManager.getLogger();
     private final ClassInstanceMultiMap<T> storage;
     private Visibility chunkStatus;
+    // Paper start - track number of items and minecarts
+    public int itemCount;
+    public int inventoryEntityCount;
+    // Paper end
 
     public EntitySection(Class<T> entityClass, Visibility status) {
         this.chunkStatus = status;
@@ -0,0 +0,0 @@ public class EntitySection<T> {
     }
 
     public void add(T obj) {
+        // Paper start
+        if (obj instanceof net.minecraft.world.entity.item.ItemEntity) {
+            this.itemCount++;
+        } else if (obj instanceof net.minecraft.world.Container) {
+            this.inventoryEntityCount++;
+        }
+        // Paper end
         this.storage.add(obj);
     }
 
     public boolean remove(T obj) {
+        // Paper start
+        if (obj instanceof net.minecraft.world.entity.item.ItemEntity) {
+            this.itemCount--;
+        } else if (obj instanceof net.minecraft.world.Container) {
+            this.inventoryEntityCount--;
+        }
+        // Paper end
         return this.storage.remove(obj);
     }
 
@@ -0,0 +0,0 @@ public class EntitySection<T> {
         for(T object : this.storage.find(type.getBaseClass())) {
             U object2 = (U)type.tryCast(object);
             if (object2 != null && filter.test(object2)) {
-                action.accept((T)object2);
+                action.accept(object2); // Paper - decompile fix
             }
         }
 
diff --git a/src/main/java/net/minecraft/world/level/entity/EntitySectionStorage.java b/src/main/java/net/minecraft/world/level/entity/EntitySectionStorage.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/world/level/entity/EntitySectionStorage.java
+++ b/src/main/java/net/minecraft/world/level/entity/EntitySectionStorage.java
@@ -0,0 +0,0 @@ public class EntitySectionStorage<T extends EntityAccess> {
 
     public LongSet getAllChunksWithExistingSections() {
         LongSet longSet = new LongOpenHashSet();
-        this.sections.keySet().forEach((sectionPos) -> {
+        this.sections.keySet().forEach((java.util.function.LongConsumer) (sectionPos) -> { // Paper - decompile fix
             longSet.add(getChunkKeyFromSectionKey(sectionPos));
         });
         return longSet;
@@ -0,0 +0,0 @@ public class EntitySectionStorage<T extends EntityAccess> {
     }
 
     public void getEntities(AABB box, Consumer<T> action) {
+        // Paper start
+        this.getEntities(box, action, false);
+    }
+    public void getEntities(AABB box, Consumer<T> action, boolean isContainerSearch) {
+        // Paper end
         this.forEachAccessibleSection(box, (entitySection) -> {
+            if (isContainerSearch && entitySection.inventoryEntityCount <= 0) return; // Paper
             entitySection.getEntities(createBoundingBoxCheck(box), action);
         });
     }
 
     public <U extends T> void getEntities(EntityTypeTest<T, U> filter, AABB box, Consumer<U> action) {
         this.forEachAccessibleSection(box, (entitySection) -> {
+            if (filter.getBaseClass() == net.minecraft.world.entity.item.ItemEntity.class && entitySection.itemCount <= 0) return; // Paper
             entitySection.getEntities(filter, createBoundingBoxCheck(box), action);
         });
     }
diff --git a/src/main/java/net/minecraft/world/level/entity/LevelEntityGetter.java b/src/main/java/net/minecraft/world/level/entity/LevelEntityGetter.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/world/level/entity/LevelEntityGetter.java
+++ b/src/main/java/net/minecraft/world/level/entity/LevelEntityGetter.java
@@ -0,0 +0,0 @@ public interface LevelEntityGetter<T extends EntityAccess> {
     <U extends T> void get(EntityTypeTest<T, U> filter, Consumer<U> action);
 
     void get(AABB box, Consumer<T> action);
+    void get(AABB box, Consumer<T> action, boolean isContainerSearch); // Paper
 
     <U extends T> void get(EntityTypeTest<T, U> filter, AABB box, Consumer<U> action);
 }
diff --git a/src/main/java/net/minecraft/world/level/entity/LevelEntityGetterAdapter.java b/src/main/java/net/minecraft/world/level/entity/LevelEntityGetterAdapter.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/world/level/entity/LevelEntityGetterAdapter.java
+++ b/src/main/java/net/minecraft/world/level/entity/LevelEntityGetterAdapter.java
@@ -0,0 +0,0 @@ public class LevelEntityGetterAdapter<T extends EntityAccess> implements LevelEn
 
     @Override
     public void get(AABB box, Consumer<T> action) {
-        this.sectionStorage.getEntities(box, action);
+        // Paper start
+        this.get(box, action, false);
+    }
+    @Override
+    public void get(AABB box, Consumer<T> action, boolean isContainerSearch) {
+        this.sectionStorage.getEntities(box, action, isContainerSearch);
+        // Paper end
     }
 
     @Override
