From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: JellySquid <jellysquid+atwork@protonmail.com>
Date: Mon, 11 May 2020 22:56:27 +0200
Subject: [PATCH] lithium MixinLandPathNodeMaker

Original code by JellySquid, licensed under GNU Lesser General Public License v3.0
you can find the original code on https://github.com/jellysquid3/lithium-fabric/tree/1.16.x/fabric (Yarn mappings)

diff --git a/src/main/java/net/minecraft/server/PathfinderNormal.java b/src/main/java/net/minecraft/server/PathfinderNormal.java
index ec55785af2b432b692d3a3bf4298ffb32489bf3b..279ca87d8826ea2696ffc08d4b52c55a5e7bd392 100644
--- a/src/main/java/net/minecraft/server/PathfinderNormal.java
+++ b/src/main/java/net/minecraft/server/PathfinderNormal.java
@@ -4,12 +4,23 @@ import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
 import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.objects.Object2BooleanMap;
 import it.unimi.dsi.fastutil.objects.Object2BooleanOpenHashMap;
+import com.google.common.collect.Sets;
+
+import it.unimi.dsi.fastutil.objects.Reference2ReferenceMap;
+import it.unimi.dsi.fastutil.objects.Reference2ReferenceOpenHashMap;
+
 import java.util.EnumSet;
 import java.util.Iterator;
 import javax.annotation.Nullable;
 
 public class PathfinderNormal extends PathfinderAbstract {
 
+	// Yatopia start
+
+    // This is not thread-safe!
+    private static final Reference2ReferenceMap<IBlockData, PathType> commonTypes = new Reference2ReferenceOpenHashMap<>();
+	// Yatopia end
+
     protected float j;
     private final Long2ObjectMap<PathType> k = new Long2ObjectOpenHashMap();
     private final Object2BooleanMap<AxisAlignedBB> l = new Object2BooleanOpenHashMap();
@@ -508,13 +519,44 @@ public class PathfinderNormal extends PathfinderAbstract {
     protected static PathType b(IBlockAccess iblockaccess, BlockPosition blockposition) {
         IBlockData iblockdata = iblockaccess.getTypeIfLoaded(blockposition); // Paper
         if (iblockdata == null) return PathType.BLOCKED; // Paper
-        Block block = iblockdata.getBlock();
-        Material material = iblockdata.getMaterial();
+        // Check early if the block is air as it will always be open regardless of other conditions
+        if(iblockdata.isAir())return PathType.OPEN;
+
+        // Get the cached type for this block state
+        PathType type = commonTypes.get(iblockdata);
+
+        // No result has been cached for this block state yet, so calculate and cache it
+        if (type == null) {
+            commonTypes.put(iblockdata, type = getPathType(iblockaccess, blockposition, iblockdata));
+        }
+        // If the node type is open, it means that we were unable to determine a more specific type, so we need
+        // to check the fallback path.
+        if (type == PathType.OPEN) {
+            // This is only ever called in vanilla after all other possibilities are exhausted, but before fluid checks
+            // It should be safe to perform it last in actuality and take advantage of the cache for fluid types as well
+            // since fluids will always pass this check.
+            if (!iblockdata.a(iblockaccess, blockposition, PathMode.LAND)) {
+                return PathType.BLOCKED;
+            }
 
-        if (iblockdata.isAir()) {
+            // All checks succeed, this path node really is open!
             return PathType.OPEN;
-        } else if (!iblockdata.a((Tag) TagsBlock.TRAPDOORS) && !iblockdata.a(Blocks.LILY_PAD)) {
-            if (iblockdata.a(Blocks.CACTUS)) {
+        }
+
+        // Return the cached value since we found an obstacle earlier
+        return type;
+
+    }
+
+	private static PathType getPathType(IBlockAccess iblockaccess, BlockPosition blockposition,
+			IBlockData iblockdata) {
+		Block block = iblockdata.getBlock();
+        Material material = iblockdata.getMaterial();
+
+        if (!block.a(TagsBlock.TRAPDOORS) && block != Blocks.LILY_PAD) {
+            if (block == Blocks.FIRE) {
+                return PathType.DAMAGE_FIRE;
+            } else if (block == Blocks.CACTUS) {
                 return PathType.DAMAGE_CACTUS;
             } else if (iblockdata.a(Blocks.SWEET_BERRY_BUSH)) {
                 return PathType.DAMAGE_OTHER;
@@ -540,7 +582,10 @@ public class PathfinderNormal extends PathfinderAbstract {
                 } else {
                     Fluid fluid = iblockdata.getFluid(); // Tuinity - remove another getType call
 
-                    return fluid.a((Tag) TagsFluid.WATER) ? PathType.WATER : (fluid.a((Tag) TagsFluid.LAVA) ? PathType.LAVA : PathType.OPEN);
+                    if(fluid.a(TagsFluid.WATER))return PathType.WATER;
+                    if(fluid.a(TagsFluid.LAVA))return PathType.LAVA;
+
+                    return PathType.OPEN;
                 }
             } else {
                 return PathType.FENCE;