Gaussian Spread

Scripts/Utils/RandomStuff.cs

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+using System;
+using Godot;
+
+namespace Cirno.Scripts.Utils;
+
+public static class RandomStuff
+{
+    public static double GaussianRandom(double mean = 0.0, double stdDev = 1.0)
+    {
+        // Box-Muller transform
+        float u1 = GD.Randf();
+        float u2 = GD.Randf();
+
+        // Ensure u1 is strictly > 0
+        while (u1 <= 0f)
+            u1 = GD.Randf();
+
+        float randStdNormal = Mathf.Sqrt(-2f * Mathf.Log(u1)) * Mathf.Sin(2f * Mathf.Pi * u2);
+        return mean + stdDev * randStdNormal;
+    }
+    
+    public static float GaussianClamped(float mean, float stdDev, float min, float max)
+    {
+        float value;
+        do
+        {
+            float u1 = GD.Randf();
+            float u2 = GD.Randf();
+
+            // Ensure u1 > 0 to avoid log(0)
+            while (u1 <= 0f) u1 = GD.Randf();
+
+            float randStdNormal = Mathf.Sqrt(-2f * Mathf.Log(u1)) * Mathf.Sin(2f * Mathf.Pi * u2);
+            value = mean + stdDev * randStdNormal;
+        }
+        while (value < min || value > max); // reject out-of-bounds values
+
+        return value;
+    }
+}

Scripts/Utils/RandomStuff.cs.uid

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+uid://tkwp2w30xi32