From 11b09cbfb3f41886de0c7c90ef52d872588f1bbc Mon Sep 17 00:00:00 2001
From: JFronny <33260128+JFronny@users.noreply.github.com>
Date: Fri, 7 Aug 2020 00:31:31 +0200
Subject: [PATCH] Simplex noise corruption, idk where it is used

---
 .../mixin/MixinSimplexNoiseSampler.java       | 84 +++++++++++++++++++
 .../io.gitlab.jfronny.quickmeth.mixins.json   |  3 +-
 2 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 src/main/java/io/gitlab/jfronny/quickmeth/mixin/MixinSimplexNoiseSampler.java

diff --git a/src/main/java/io/gitlab/jfronny/quickmeth/mixin/MixinSimplexNoiseSampler.java b/src/main/java/io/gitlab/jfronny/quickmeth/mixin/MixinSimplexNoiseSampler.java
new file mode 100644
index 0000000..3e0c265
--- /dev/null
+++ b/src/main/java/io/gitlab/jfronny/quickmeth/mixin/MixinSimplexNoiseSampler.java
@@ -0,0 +1,84 @@
+package io.gitlab.jfronny.quickmeth.mixin;
+
+import io.gitlab.jfronny.quickmeth.quickmeth;
+import net.minecraft.util.math.MathHelper;
+import net.minecraft.util.math.noise.SimplexNoiseSampler;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+
+@Mixin(SimplexNoiseSampler.class)
+public class MixinSimplexNoiseSampler {
+    @Shadow @Final
+    private static double SKEW_FACTOR_2D;
+    @Shadow @Final
+    private static double UNSKEW_FACTOR_2D;
+    @Shadow @Final
+    protected static int[][] gradients;
+    @Shadow @Final
+    private int[] permutations;
+    @Overwrite
+    public double sample(double x, double y) {
+        x = quickmeth.BoxedInvert(x);
+        y = quickmeth.BoxedInvert(y);
+        double d = (x + y) * SKEW_FACTOR_2D;
+        int i = MathHelper.floor(x + d);
+        int j = MathHelper.floor(y + d);
+        double e = (double)(i + j) * UNSKEW_FACTOR_2D;
+        double f = (double)i - e;
+        double g = (double)j - e;
+        double h = x - f;
+        double k = y - g;
+        byte n;
+        byte o;
+        if (h > k) {
+            n = 1;
+            o = 0;
+        } else {
+            n = 0;
+            o = 1;
+        }
+
+        double p = h - (double)n + UNSKEW_FACTOR_2D;
+        double q = k - (double)o + UNSKEW_FACTOR_2D;
+        double r = h - 1.0D + 2.0D * UNSKEW_FACTOR_2D;
+        double s = k - 1.0D + 2.0D * UNSKEW_FACTOR_2D;
+        int t = i & 255;
+        int u = j & 255;
+        int v = getGradient(t + this.getGradient(u)) % 12;
+        int w = getGradient(t + n + this.getGradient(u + o)) % 12;
+        int z = getGradient(t + 1 + this.getGradient(u + 1)) % 12;
+        double aa = mgrad(v, h, k, 0.0D, 0.5D);
+        double ab = mgrad(w, p, q, 0.0D, 0.5D);
+        double ac = mgrad(z, r, s, 0.0D, 0.5D);
+        return quickmeth.BoxedInvert(70.0D * (aa + ab + ac));
+    }
+
+    @Overwrite
+    private int getGradient(int hash) {
+        return this.permutations[hash & 255] & 255;
+    }
+
+    private static double mgrad(int hash, double x, double y, double z, double d) {
+        x = quickmeth.BoxedInvert(x);
+        y = quickmeth.BoxedInvert(y);
+        z = quickmeth.BoxedInvert(z);
+        d = quickmeth.BoxedInvert(d);
+
+        double e = d - x * x - y * y - z * z;
+        double g;
+        if (e < 0.0D) {
+            g = 0.0D;
+        } else {
+            e *= e;
+            g = e * e * mdot(gradients[hash], x, y, z);
+        }
+
+        return g;
+    }
+
+    private static double mdot(int[] gArr, double x, double y, double z) {
+        return quickmeth.BoxedInvert((double)gArr[0] * x + (double)gArr[1] * y + (double)gArr[2] * z);
+    }
+}
diff --git a/src/main/resources/io.gitlab.jfronny.quickmeth.mixins.json b/src/main/resources/io.gitlab.jfronny.quickmeth.mixins.json
index 7a6e3cb..a924ebe 100644
--- a/src/main/resources/io.gitlab.jfronny.quickmeth.mixins.json
+++ b/src/main/resources/io.gitlab.jfronny.quickmeth.mixins.json
@@ -6,7 +6,8 @@
   "mixins": [
     "MathHelperMixin",
     "MixinOctavePerlinNoiseSampler",
-    "MixinPerlinNoiseSampler"
+    "MixinPerlinNoiseSampler",
+    "MixinSimplexNoiseSampler"
   ],
   "client": [
   ],