From c96127fde7fcac00acb6469394301b8729617137 Mon Sep 17 00:00:00 2001
From: dfsek <dfsek@protonmail.com>
Date: Fri, 20 Nov 2020 23:09:00 -0700
Subject: [PATCH] Slightly improve performance of NoiseFunction2

---
 .../dfsek/terra/config/base/ConfigUtil.java   |  3 --
 .../com/dfsek/terra/math/NoiseFunction2.java  | 25 +----------------
 src/main/resources/config.yml                 |  1 -
 src/test/java/NoiseTest.java                  | 28 +++++++++++++++++++
 4 files changed, 29 insertions(+), 28 deletions(-)
 create mode 100644 src/test/java/NoiseTest.java

diff --git a/src/main/java/com/dfsek/terra/config/base/ConfigUtil.java b/src/main/java/com/dfsek/terra/config/base/ConfigUtil.java
index 70c4fed2e..d9409ee4a 100644
--- a/src/main/java/com/dfsek/terra/config/base/ConfigUtil.java
+++ b/src/main/java/com/dfsek/terra/config/base/ConfigUtil.java
@@ -18,7 +18,6 @@ import java.io.IOException;
 import java.net.URISyntaxException;
 import java.time.Duration;
 import java.util.EnumSet;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
 import java.util.Set;
@@ -29,7 +28,6 @@ public final class ConfigUtil {
     public static boolean debug;
     public static long dataSave; // Period of population data saving, in ticks.
     public static boolean masterDisableCaves;
-    public static int cacheSize;
 
     public static void loadConfig(JavaPlugin main) {
         main.saveDefaultConfig();
@@ -38,7 +36,6 @@ public final class ConfigUtil {
         LangUtil.load(config.getString("language", "en_us"), main);
 
         debug = config.getBoolean("debug", false);
-        cacheSize = config.getInt("cache-size", 3);
         dataSave = Duration.parse(Objects.requireNonNull(config.getString("data-save", "PT6M"))).toMillis() / 20L;
         masterDisableCaves = config.getBoolean("master-disable.caves", false);
 
diff --git a/src/main/java/com/dfsek/terra/math/NoiseFunction2.java b/src/main/java/com/dfsek/terra/math/NoiseFunction2.java
index 2545e7e85..898b760c2 100644
--- a/src/main/java/com/dfsek/terra/math/NoiseFunction2.java
+++ b/src/main/java/com/dfsek/terra/math/NoiseFunction2.java
@@ -1,6 +1,5 @@
 package com.dfsek.terra.math;
 
-import com.dfsek.terra.config.base.ConfigUtil;
 import com.dfsek.terra.generation.config.NoiseBuilder;
 import org.polydev.gaea.math.FastNoiseLite;
 import parsii.eval.Expression;
@@ -8,7 +7,6 @@ import parsii.eval.Expression;
 import java.util.List;
 
 public class NoiseFunction2 implements NoiseFunction {
-    private final Cache cache = new Cache();
     private final FastNoiseLite gen;
 
     public NoiseFunction2(long seed, NoiseBuilder builder) {
@@ -22,32 +20,11 @@ public class NoiseFunction2 implements NoiseFunction {
 
     @Override
     public double eval(List<Expression> list) {
-        return cache.get(list.get(0).evaluate(), list.get(1).evaluate());
+        return gen.getNoise(list.get(0).evaluate(), list.get(1).evaluate());
     }
 
     @Override
     public boolean isNaturalFunction() {
         return true;
     }
-
-    private final class Cache {
-        private final double[] cacheX = new double[ConfigUtil.cacheSize];
-        private final double[] cacheZ = new double[ConfigUtil.cacheSize];
-        private final double[] cacheValues = new double[ConfigUtil.cacheSize];
-
-        public double get(double x, double z) {
-            for(int i = 0; i < cacheX.length; i++) {
-                if(cacheX[i] == x && cacheZ[i] == z) return cacheValues[i];
-            }
-            cacheX[0] = x;
-            cacheZ[0] = z;
-            cacheValues[0] = gen.getNoise(x, z);
-            for(int i = 0; i < cacheX.length - 1; i++) {
-                cacheX[i + 1] = cacheX[i];
-                cacheZ[i + 1] = cacheZ[i];
-                cacheValues[i + 1] = cacheValues[i];
-            }
-            return cacheValues[0];
-        }
-    }
 }
diff --git a/src/main/resources/config.yml b/src/main/resources/config.yml
index d87580b25..3488f1a05 100644
--- a/src/main/resources/config.yml
+++ b/src/main/resources/config.yml
@@ -3,6 +3,5 @@ data-save: PT6M
 language: "en_us"
 fail-type: SHUTDOWN
 dump-default: true
-cache-size: 8
 master-disable:
   caves: false
\ No newline at end of file
diff --git a/src/test/java/NoiseTest.java b/src/test/java/NoiseTest.java
new file mode 100644
index 000000000..b11cacc94
--- /dev/null
+++ b/src/test/java/NoiseTest.java
@@ -0,0 +1,28 @@
+import com.dfsek.terra.generation.config.NoiseBuilder;
+import com.dfsek.terra.math.NoiseFunction2;
+import org.junit.jupiter.api.Test;
+import parsii.eval.Expression;
+
+import java.util.Arrays;
+
+public class NoiseTest {
+    @Test
+    public void noise() {
+        NoiseFunction2 noiseFunction = new NoiseFunction2(12345, new NoiseBuilder());
+
+        for(int i = 0; i < 10; i++) {
+            long l = System.nanoTime();
+            for(int j = 0; j < 1000000; j++) {
+                noiseFunction.eval(Arrays.asList(get(j), get(i)));
+                noiseFunction.eval(Arrays.asList(get(j), get(i)));
+                noiseFunction.eval(Arrays.asList(get(j), get(i)));
+            }
+            double n = System.nanoTime() - l;
+            System.out.println(n / 1000000 + "ms");
+        }
+    }
+
+    private Expression get(double val) {
+        return () -> val;
+    }
+}