From 1a5742af0fe65ef4926dc63cb77b6f5099dced31 Mon Sep 17 00:00:00 2001
From: SuperCoder79 <25208576+SuperCoder7979@users.noreply.github.com>
Date: Sun, 4 Oct 2020 21:11:48 -0400
Subject: [PATCH] Change climate offsetting to random instead of bitmask
 (#1690)

---
 .../world/layer/RainfallNoiseLayer.java       | 20 ++++++++++++++++---
 .../world/layer/TemperatureNoiseLayer.java    | 20 ++++++++++++++++---
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/src/main/java/biomesoplenty/common/world/layer/RainfallNoiseLayer.java b/src/main/java/biomesoplenty/common/world/layer/RainfallNoiseLayer.java
index c5209bea3..0f3cc224a 100644
--- a/src/main/java/biomesoplenty/common/world/layer/RainfallNoiseLayer.java
+++ b/src/main/java/biomesoplenty/common/world/layer/RainfallNoiseLayer.java
@@ -7,6 +7,8 @@
  ******************************************************************************/
 package biomesoplenty.common.world.layer;
 
+import java.util.Random;
+
 import biomesoplenty.common.world.SimplexNoise;
 import biomesoplenty.common.world.layer.traits.IBOPAreaTransformer0;
 import biomesoplenty.common.world.layer.traits.IBOPContextExtended;
@@ -19,6 +21,10 @@ public enum RainfallNoiseLayer implements IBOPAreaTransformer0
 
     private final double scale;
 
+    private long seed;
+    private double xOffset;
+    private double zOffset;
+
     RainfallNoiseLayer(double scale)
     {
         this.scale = scale;
@@ -27,9 +33,17 @@ public enum RainfallNoiseLayer implements IBOPAreaTransformer0
     @Override
     public int applyPixel(IBOPContextExtended context, int x, int z)
     {
-        double xOffset = (double)(context.getWorldSeed() & 0xFFFFFF) * 0.000003D;
-        double zOffset = (double)(context.getWorldSeed() & 0xFFFFFF) * 0.000004D;
-        double noiseVal = SimplexNoise.noise((x + xOffset) * this.scale, (z + zOffset) * this.scale);
+        long seed = context.getWorldSeed();
+
+        // If the seed has changed, re-initialize offsets
+        if (this.seed != seed) {
+            Random random = new Random(seed - 123);
+            this.xOffset = random.nextDouble() * 128;
+            this.zOffset = random.nextDouble() * 128;
+            this.seed = seed;
+        }
+
+        double noiseVal = SimplexNoise.noise((x + this.xOffset) * this.scale, (z + this.zOffset) * this.scale);
 
         // boundaries were determined empirically by analyzing statistically output from the SimplexNoise function, and splitting into 12 equally likely groups
         if (noiseVal < -0.637D) return 0;
diff --git a/src/main/java/biomesoplenty/common/world/layer/TemperatureNoiseLayer.java b/src/main/java/biomesoplenty/common/world/layer/TemperatureNoiseLayer.java
index c6686e67a..ea8ba203f 100644
--- a/src/main/java/biomesoplenty/common/world/layer/TemperatureNoiseLayer.java
+++ b/src/main/java/biomesoplenty/common/world/layer/TemperatureNoiseLayer.java
@@ -7,6 +7,8 @@
  ******************************************************************************/
 package biomesoplenty.common.world.layer;
 
+import java.util.Random;
+
 import biomesoplenty.common.world.SimplexNoise;
 import biomesoplenty.common.world.layer.traits.IBOPAreaTransformer0;
 import biomesoplenty.common.world.layer.traits.IBOPContextExtended;
@@ -19,6 +21,10 @@ public enum TemperatureNoiseLayer implements IBOPAreaTransformer0
 
     private final double scale;
 
+    private long seed;
+    private double xOffset;
+    private double zOffset;
+
     TemperatureNoiseLayer(double scale)
     {
         this.scale = scale;
@@ -27,9 +33,17 @@ public enum TemperatureNoiseLayer implements IBOPAreaTransformer0
     @Override
     public int applyPixel(IBOPContextExtended context, int x, int z)
     {
-        double xOffset = (double)(context.getWorldSeed() & 0xFFFFFF) * 0.000001D;
-        double zOffset = (double)(context.getWorldSeed() & 0xFFFFFF) * 0.000002D;
-        double noiseVal = SimplexNoise.noise((x + xOffset) * this.scale, (z + zOffset) * this.scale);
+        long seed = context.getWorldSeed();
+
+        // If the seed has changed, re-initialize offsets
+        if (this.seed != seed) {
+            Random random = new Random(seed + 123);
+            this.xOffset = random.nextDouble() * 128;
+            this.zOffset = random.nextDouble() * 128;
+            this.seed = seed;
+        }
+
+        double noiseVal = SimplexNoise.noise((x + this.xOffset) * this.scale, (z + this.zOffset) * this.scale);
 
         // boundaries were determined empirically by analyzing statistically output from the SimplexNoise function, and splitting into 9 equally likely groups
         if (noiseVal < -0.619D) return 0;