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NitroxModel/DataStructures/GameLogic/RandomStartGenerator.cs

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+using System;
+using System.Collections.Generic;
+using NitroxModel.DataStructures.Unity;
+
+namespace NitroxModel.DataStructures.GameLogic;
+
+public class RandomStartGenerator
+{
+    private readonly IPixelProvider pixelProvider;
+
+    public RandomStartGenerator(IPixelProvider pixelProvider)
+    {
+        this.pixelProvider = pixelProvider;
+    }
+
+    public NitroxVector3 GenerateRandomStartPosition(Random rnd)
+    {
+        for (int i = 0; i < 1000; i++)
+        {
+            float normalizedX = (float)rnd.NextDouble();
+            float normalizedZ = (float)rnd.NextDouble();
+
+            if (IsStartPointValid(normalizedX, normalizedZ))
+            {
+                float x = 4096f * normalizedX - 2048f; // normalizedX = (x + 2048) / 4096
+                float z = 4096f * normalizedZ - 2048f;
+                return new NitroxVector3(x, 0, z);
+            }
+        }
+
+        return NitroxVector3.Zero;
+    }
+
+    public List<NitroxVector3> GenerateRandomStartPositions(string seed)
+    {
+        Random rnd = new(seed.GetHashCode());
+        List<NitroxVector3> list = new();
+
+        for (int i = 0; i < 1000; i++)
+        {
+            float normalizedX = (float)rnd.NextDouble();
+            float normalizedZ = (float)rnd.NextDouble();
+
+            if (IsStartPointValid(normalizedX, normalizedZ))
+            {
+                float x = 4096f * normalizedX - 2048f; // normalizedX = (x + 2048) / 4096
+                float z = 4096f * normalizedZ - 2048f;
+                list.Add(new NitroxVector3(x, 0, z));
+            }
+        }
+
+        return list;
+    }
+
+    private bool IsStartPointValid(float normalizedX, float normalizedZ)
+    {
+        int textureX = (int)(normalizedX * 512);
+        int textureZ = (int)(normalizedZ * 512);
+
+        return pixelProvider.GetGreen(textureX, textureZ) > 127;
+    }
+
+    /// <summary>
+    ///     API for getting pixels from an underlying texture.
+    /// </summary>
+    public interface IPixelProvider
+    {
+        byte GetRed(int x, int y);
+        byte GetGreen(int x, int y);
+        byte GetBlue(int x, int y);
+    }
+}