Paper/Spigot-Server-Patches/0248-Improve-Structures-Checking.patch

From 13d727f38a8615e821d1794176154b34780c0c19 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 11 Nov 2017 17:57:39 -0500
Subject: [PATCH] Improve Structures Checking

Improves performance by keying every chunk thats part of a structure to a hashmap
instead of only the first one.

This allows us to avoid iterating the entire structures value set to see
if a block position is inside of a structure.

This should have pretty decent performance improvement to any standard world
that has been around for a whilewith lots of structures due to ineffeciencies
in how MC stores structures (even unloaded chunks has structured data loaded)

diff --git a/src/main/java/net/minecraft/server/StructureBoundingBox.java b/src/main/java/net/minecraft/server/StructureBoundingBox.java
index db419cd99..d9329bd42 100644
--- a/src/main/java/net/minecraft/server/StructureBoundingBox.java
+++ b/src/main/java/net/minecraft/server/StructureBoundingBox.java
@@ -4,12 +4,14 @@ import com.google.common.base.MoreObjects;
 
 public class StructureBoundingBox {
 
-    public int a;
-    public int b;
-    public int c;
-    public int d;
-    public int e;
-    public int f;
+    public int a; // Paper - If changes, verify low/high getters
+    public int b; // Paper - If changes, verify low/high getters
+    public int c; // Paper - If changes, verify low/high getters
+    public int d; // Paper - If changes, verify low/high getters
+    public int e; // Paper - If changes, verify low/high getters
+    public int f; // Paper - If changes, verify low/high getters
+    public BaseBlockPosition getLowPosition() { return new BaseBlockPosition(a, b, c); } // Paper
+    public BaseBlockPosition getHighPosition() { return new BaseBlockPosition(d, e, f); } // Paper
 
     public StructureBoundingBox() {}
 
@@ -114,6 +116,7 @@ public class StructureBoundingBox {
         this.f += k;
     }
 
+    public boolean contains(BaseBlockPosition baseblockposition) { return b(baseblockposition); } // Paper - OBFHELPER
     public boolean b(BaseBlockPosition baseblockposition) {
         return baseblockposition.getX() >= this.a && baseblockposition.getX() <= this.d && baseblockposition.getZ() >= this.c && baseblockposition.getZ() <= this.f && baseblockposition.getY() >= this.b && baseblockposition.getY() <= this.e;
     }
diff --git a/src/main/java/net/minecraft/server/StructureGenerator.java b/src/main/java/net/minecraft/server/StructureGenerator.java
index e8263baa4..f4dfba8f3 100644
--- a/src/main/java/net/minecraft/server/StructureGenerator.java
+++ b/src/main/java/net/minecraft/server/StructureGenerator.java
@@ -6,6 +6,7 @@ import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
 import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.objects.ObjectIterator;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Random;
 import javax.annotation.Nullable;
 
@@ -14,6 +15,7 @@ public abstract class StructureGenerator extends WorldGenBase {
     private final Timing timing = MinecraftTimings.getStructureTiming(this); // Paper
     private PersistentStructure a;
     protected Long2ObjectMap<StructureStart> c = new Long2ObjectOpenHashMap(1024);
+    protected Long2ObjectMap<StructureStart> allStructures = new Long2ObjectOpenHashMap(1024); // Paper - Holds ref to structures for every chunk its part of, where as the one above this only holds the vanilla oriented ones.
 
     public StructureGenerator() {}
 
@@ -29,6 +31,7 @@ public abstract class StructureGenerator extends WorldGenBase {
                 if (this.a(i, j)) {
                     StructureStart structurestart = this.b(i, j);
 
+                    populateStructure(structurestart); // Paper
                     this.c.put(ChunkCoordIntPair.a(i, j), structurestart);
                     if (structurestart.a()) {
                         this.a(i, j, structurestart);
@@ -106,6 +109,19 @@ public abstract class StructureGenerator extends WorldGenBase {
 
     @Nullable
     protected StructureStart c(BlockPosition blockposition) {
+        // Paper start - replace method
+        StructureStart structureStart = allStructures.get(ChunkCoordIntPair.asLong(blockposition));
+        if (structureStart != null && structureStart.isSizeable() && structureStart.getBoundingBox().contains(blockposition)) {
+            List<StructurePiece> structurePieces = structureStart.getStructurePieces();
+            for (StructurePiece piece : structurePieces) {
+                if (piece.getBoundingBox().contains(blockposition)) {
+                    return structureStart;
+                }
+            }
+        }
+
+        return null;
+        /*
         ObjectIterator objectiterator = this.c.values().iterator();
 
         while (objectiterator.hasNext()) {
@@ -125,11 +141,16 @@ public abstract class StructureGenerator extends WorldGenBase {
         }
 
         return null;
+        */
     }
 
     public boolean a(World world, BlockPosition blockposition) {
         if (this.g == null) return false; // Paper
         this.a(world);
+        // Paper start - Replace method
+        StructureStart structureStart = this.allStructures.get(ChunkCoordIntPair.asLong(blockposition));
+        return structureStart != null && structureStart.isSizeable() && structureStart.getBoundingBox().contains(blockposition);
+        /* // comment out rest
         ObjectIterator objectiterator = this.c.values().iterator();
 
         StructureStart structurestart;
@@ -142,7 +163,7 @@ public abstract class StructureGenerator extends WorldGenBase {
             structurestart = (StructureStart) objectiterator.next();
         } while (!structurestart.a() || !structurestart.b().b((BaseBlockPosition) blockposition));
 
-        return true;
+        return true;*/ // Paper end
     }
 
     @Nullable
@@ -177,6 +198,7 @@ public abstract class StructureGenerator extends WorldGenBase {
                             StructureStart structurestart = WorldGenFactory.a(nbttagcompound1, world);
 
                             if (structurestart != null) {
+                                populateStructure(structurestart); // Paper
                                 this.c.put(ChunkCoordIntPair.a(i, j), structurestart);
                             }
                         }
@@ -187,6 +209,27 @@ public abstract class StructureGenerator extends WorldGenBase {
 
     }
 
+    // Paper start
+    private void populateStructure(StructureStart structurestart) {
+        for (StructurePiece piece : structurestart.getStructurePieces()) {
+            populateStructure(structurestart, piece.getBoundingBox());
+        }
+        populateStructure(structurestart, structurestart.getBoundingBox());
+    }
+    private void populateStructure(StructureStart structurestart, StructureBoundingBox bb) {
+        if (bb == null) {
+            return;
+        }
+        final BaseBlockPosition low = bb.getLowPosition();
+        final BaseBlockPosition high = bb.getHighPosition();
+        for (int x = low.getX() >> 4, maxX = high.getX() >> 4; x <= maxX; x++) {
+            for (int z = low.getZ() >> 4, maxZ = high.getZ() >> 4; z <= maxZ; z++) {
+                allStructures.put(ChunkCoordIntPair.asLong(x, z), structurestart);
+            }
+        }
+    }
+    // Paper end
+
     private void a(int i, int j, StructureStart structurestart) {
         this.a.a(structurestart.a(i, j), i, j);
         this.a.c();
diff --git a/src/main/java/net/minecraft/server/StructurePiece.java b/src/main/java/net/minecraft/server/StructurePiece.java
index 93903bc67..fcc13f811 100644
--- a/src/main/java/net/minecraft/server/StructurePiece.java
+++ b/src/main/java/net/minecraft/server/StructurePiece.java
@@ -53,6 +53,7 @@ public abstract class StructurePiece {
 
     public abstract boolean a(World world, Random random, StructureBoundingBox structureboundingbox);
 
+    public StructureBoundingBox getBoundingBox() { return d(); } // Paper - OBFHELPER
     public StructureBoundingBox d() {
         return this.l;
     }
diff --git a/src/main/java/net/minecraft/server/StructureStart.java b/src/main/java/net/minecraft/server/StructureStart.java
index b6abc74e0..f9bb953d0 100644
--- a/src/main/java/net/minecraft/server/StructureStart.java
+++ b/src/main/java/net/minecraft/server/StructureStart.java
@@ -19,10 +19,12 @@ public abstract class StructureStart {
         this.d = j;
     }
 
+    public StructureBoundingBox getBoundingBox() { return b(); } // Paper - OBFHELPER
     public StructureBoundingBox b() {
         return this.b;
     }
 
+    public List<StructurePiece> getStructurePieces() { return c(); } // Paper - OBFHELPER
     public List<StructurePiece> c() {
         return this.a;
     }
@@ -137,7 +139,7 @@ public abstract class StructureStart {
 
     }
 
-    public boolean a() {
+    public boolean isSizeable() { return a(); } public boolean a() { // Paper - OBFHELPER
         return true;
     }
 
-- 
2.18.0