10 files changed, 336 insertions, 213 deletions
diff --git a/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/FlattenArea.cs b/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/FlattenArea.cs
index 4551f53..007d37e 100644
--- a/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/FlattenArea.cs
+++ b/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/FlattenArea.cs
@@ -58,12 +58,14 @@ namespace OpenSim.Region.Environment.Modules.Terrain.FloodBrushes
            avg = sum / steps;
+            double str = 0.1 * strength; // == 0.2 in the default client
            for (x = 0; x < map.Width; x++)
            {
                for (y = 0; y < map.Height; y++)
                {
                    if (fillArea[x, y] == true)
-                        map[x, y] = avg;
+                        map[x, y] = (map[x, y] * (1.0 - str)) + (avg * str);
                }
            }
        }
diff --git a/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/NoiseArea.cs b/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/NoiseArea.cs
index 6063b2f..95ad57d 100644
--- a/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/NoiseArea.cs
+++ b/OpenSim/Region/Environment/Modules/Terrain/FloodBrushes/NoiseArea.cs
@@ -31,65 +31,6 @@ namespace OpenSim.Region.Environment.Modules.Terrain.FloodBrushes
 {
    public class NoiseArea : ITerrainFloodEffect
    {
-        private double Noise(int x, int y)
-        {
-            // TODO: Seed
-            int n = x + y * 57;
-            n = (n<<13) ^ n;
-            return (1.0 - ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0);
-        }
-        private double SmoothedNoise1(int x, int y)
-        {
-            double corners = (Noise(x - 1, y - 1) + Noise(x + 1, y - 1) + Noise(x - 1, y + 1) + Noise(x + 1, y + 1)) / 16;
-            double sides = (Noise(x - 1, y) + Noise(x + 1, y) + Noise(x, y - 1) + Noise(x, y + 1)) / 8;
-            double center = Noise(x, y) / 4;
-            return corners + sides + center;
-        }
-        private double Interpolate(double x, double y, double z)
-        {
-            return (x * (1.0 - z)) + (y * z);
-        }
-        private double InterpolatedNoise(double x, double y)
-        {
-            int integer_X = (int)(x);
-            double fractional_X = x - integer_X;
-            int integer_Y = (int)y;
-            double fractional_Y = y - integer_Y;
-            double v1 = SmoothedNoise1(integer_X, integer_Y);
-            double v2 = SmoothedNoise1(integer_X + 1, integer_Y);
-            double v3 = SmoothedNoise1(integer_X, integer_Y + 1);
-            double v4 = SmoothedNoise1(integer_X + 1, integer_Y + 1);
-            double i1 = Interpolate(v1, v2, fractional_X);
-            double i2 = Interpolate(v3, v4, fractional_X);
-            return Interpolate(i1, i2, fractional_Y);
-        }
-        private double PerlinNoise2D(double x, double y)
-        {
-            int octaves = 1;
-            double persistence = 0.0005;
-            double frequency = 0.0;
-            double amplitude = 0.0;
-            double total = 0.0;
-            for (int i = 0; i < octaves; i++)
-            {
-                frequency = System.Math.Pow(2, i);
-                amplitude = System.Math.Pow(persistence, i);
-                total += InterpolatedNoise(x * frequency, y * frequency) * amplitude;
-            }
-            return total;
-        }
        #region ITerrainFloodEffect Members
        public void FloodEffect(ITerrainChannel map, bool[,] fillArea, double strength)
@@ -101,11 +42,9 @@ namespace OpenSim.Region.Environment.Modules.Terrain.FloodBrushes
                {
                    if (fillArea[x, y] == true)
                    {
-                        lock (OpenSim.Framework.Util.RandomClass)
+                        double noise = TerrainUtil.PerlinNoise2D((double)x / (double)Framework.Constants.RegionSize, (double)y / (double)Framework.Constants.RegionSize, 8, 1.0);
-                        {
-                            double noise = PerlinNoise2D(x, y);//OpenSim.Framework.Util.RandomClass.NextDouble();
+                        map[x, y] += noise * strength;
-                            map[x, y] += (noise /*- 0.5*/) * strength;
-                        }
                    }
                }
            }
diff --git a/OpenSim/Region/Environment/Modules/Terrain/ITerrainEffect.cs b/OpenSim/Region/Environment/Modules/Terrain/ITerrainEffect.cs
new file mode 100644
index 0000000..e7fcf68
--- /dev/null
+++ b/OpenSim/Region/Environment/Modules/Terrain/ITerrainEffect.cs
@@ -0,0 +1,36 @@
+/*
+* Copyright (c) Contributors, http://opensimulator.org/
+* See CONTRIBUTORS.TXT for a full list of copyright holders.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*     * Redistributions of source code must retain the above copyright
+*       notice, this list of conditions and the following disclaimer.
+*     * Redistributions in binary form must reproduce the above copyright
+*       notice, this list of conditions and the following disclaimer in the
+*       documentation and/or other materials provided with the distribution.
+*     * Neither the name of the OpenSim Project nor the
+*       names of its contributors may be used to endorse or promote products
+*       derived from this software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+* 
+*/
+using OpenSim.Region.Environment.Interfaces;
+namespace OpenSim.Region.Environment.Modules.Terrain
+{
+    public interface ITerrainEffect
+    {
+        void RunEffect(ITerrainChannel map, double strength);
+    }
+}
diff --git a/OpenSim/Region/Environment/Modules/Terrain/ITerrainFloodEffect.cs b/OpenSim/Region/Environment/Modules/Terrain/ITerrainFloodEffect.cs
new file mode 100644
index 0000000..aabd19b
--- /dev/null
+++ b/OpenSim/Region/Environment/Modules/Terrain/ITerrainFloodEffect.cs
@@ -0,0 +1,37 @@
+/*
+* Copyright (c) Contributors, http://opensimulator.org/
+* See CONTRIBUTORS.TXT for a full list of copyright holders.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*     * Redistributions of source code must retain the above copyright
+*       notice, this list of conditions and the following disclaimer.
+*     * Redistributions in binary form must reproduce the above copyright
+*       notice, this list of conditions and the following disclaimer in the
+*       documentation and/or other materials provided with the distribution.
+*     * Neither the name of the OpenSim Project nor the
+*       names of its contributors may be used to endorse or promote products
+*       derived from this software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+* 
+*/
+using OpenSim.Region.Environment.Interfaces;
+using System;
+namespace OpenSim.Region.Environment.Modules.Terrain
+{
+    public interface ITerrainFloodEffect
+    {
+        void FloodEffect(ITerrainChannel map, Boolean[,] fillArea, double strength);
+    }
+}
diff --git a/OpenSim/Region/Environment/Modules/Terrain/ITerrainLoader.cs b/OpenSim/Region/Environment/Modules/Terrain/ITerrainLoader.cs
new file mode 100644
index 0000000..b67c8f2
--- /dev/null
+++ b/OpenSim/Region/Environment/Modules/Terrain/ITerrainLoader.cs
@@ -0,0 +1,37 @@
+/*
+* Copyright (c) Contributors, http://opensimulator.org/
+* See CONTRIBUTORS.TXT for a full list of copyright holders.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*     * Redistributions of source code must retain the above copyright
+*       notice, this list of conditions and the following disclaimer.
+*     * Redistributions in binary form must reproduce the above copyright
+*       notice, this list of conditions and the following disclaimer in the
+*       documentation and/or other materials provided with the distribution.
+*     * Neither the name of the OpenSim Project nor the
+*       names of its contributors may be used to endorse or promote products
+*       derived from this software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+* 
+*/
+using OpenSim.Region.Environment.Interfaces;
+namespace OpenSim.Region.Environment.Modules.Terrain
+{
+    public interface ITerrainLoader
+    {
+        ITerrainChannel LoadFile(string filename);
+        void SaveFile(string filename, ITerrainChannel map);
+    }
+}
diff --git a/OpenSim/Region/Environment/Modules/Terrain/ITerrainPaintableEffect.cs b/OpenSim/Region/Environment/Modules/Terrain/ITerrainPaintableEffect.cs
new file mode 100644
index 0000000..cf1ea4e
--- /dev/null
+++ b/OpenSim/Region/Environment/Modules/Terrain/ITerrainPaintableEffect.cs
@@ -0,0 +1,36 @@
+/*
+* Copyright (c) Contributors, http://opensimulator.org/
+* See CONTRIBUTORS.TXT for a full list of copyright holders.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*     * Redistributions of source code must retain the above copyright
+*       notice, this list of conditions and the following disclaimer.
+*     * Redistributions in binary form must reproduce the above copyright
+*       notice, this list of conditions and the following disclaimer in the
+*       documentation and/or other materials provided with the distribution.
+*     * Neither the name of the OpenSim Project nor the
+*       names of its contributors may be used to endorse or promote products
+*       derived from this software without specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+* 
+*/
+using OpenSim.Region.Environment.Interfaces;
+namespace OpenSim.Region.Environment.Modules.Terrain
+{
+    public interface ITerrainPaintableEffect
+    {
+        void PaintEffect(ITerrainChannel map, double x, double y, double strength, double duration);
+    }
+}
diff --git a/OpenSim/Region/Environment/Modules/Terrain/PaintBrushes/NoiseSphere.cs b/OpenSim/Region/Environment/Modules/Terrain/PaintBrushes/NoiseSphere.cs
index 4a03a17..9754a99 100644
--- a/OpenSim/Region/Environment/Modules/Terrain/PaintBrushes/NoiseSphere.cs
+++ b/OpenSim/Region/Environment/Modules/Terrain/PaintBrushes/NoiseSphere.cs
@@ -57,15 +57,10 @@ namespace OpenSim.Region.Environment.Modules.Terrain.PaintBrushes
                    z *= z;
                    z -= ((x - rx) * (x - rx)) + ((y - ry) * (y - ry));
-                    double noise;
+                    double noise = TerrainUtil.PerlinNoise2D((double)x / (double)Framework.Constants.RegionSize, (double)y / (double)Framework.Constants.RegionSize, 8, 1.0);
-                    lock (Util.RandomClass)
-                    {
-                        noise = Util.RandomClass.NextDouble();
-                    }
                    if (z > 0.0)
-                        map[x, y] += (noise - 0.5) * z * duration;
+                        map[x, y] += noise * z * duration;
                }
            }
        }
diff --git a/OpenSim/Region/Environment/Modules/Terrain/TerrainChannel.cs b/OpenSim/Region/Environment/Modules/Terrain/TerrainChannel.cs
new file mode 100644
index 0000000..59937d1
--- /dev/null
+++ b/OpenSim/Region/Environment/Modules/Terrain/TerrainChannel.cs
@@ -0,0 +1,119 @@
+using OpenSim.Framework;
+using OpenSim.Region.Environment.Interfaces;
+namespace OpenSim.Region.Environment.Modules.Terrain
+{
+    /// <summary>
+    /// A new version of the old Channel class, simplified
+    /// </summary>
+    public class TerrainChannel : ITerrainChannel
+    {
+        private double[,] map;
+        private bool[,] taint;
+        public int Width
+        {
+            get { return map.GetLength(0); }
+        }
+        public int Height
+        {
+            get { return map.GetLength(1); }
+        }
+        public TerrainChannel Copy()
+        {
+            TerrainChannel copy = new TerrainChannel(false);
+            copy.map = (double[,])this.map.Clone();
+            return copy;
+        }
+        public float[] GetFloatsSerialised()
+        {
+            float[] heights = new float[Width * Height];
+            int i;
+            for (i = 0; i < Width * Height; i++)
+            {
+                heights[i] = (float)map[i % Width, i / Width];
+            }
+            return heights;
+        }
+        public double[,] GetDoubles()
+        {
+            return map;
+        }
+        public double this[int x, int y]
+        {
+            get
+            {
+                return map[x, y];
+            }
+            set
+            {
+                if (map[x, y] != value)
+                {
+                    taint[x / 16, y / 16] = true;
+                    map[x, y] = value;
+                }
+            }
+        }
+        public bool Tainted(int x, int y)
+        {
+            if (taint[x / 16, y / 16] != false)
+            {
+                taint[x / 16, y / 16] = false;
+                return true;
+            }
+            else
+            {
+                return false;
+            }
+        }
+        public TerrainChannel()
+        {
+            map = new double[Constants.RegionSize, Constants.RegionSize];
+            taint = new bool[Constants.RegionSize / 16, Constants.RegionSize / 16];
+            int x, y;
+            for (x = 0; x < Constants.RegionSize; x++)
+            {
+                for (y = 0; y < Constants.RegionSize; y++)
+                {
+                    map[x, y] = 60.0 - // 60 = Sphere Radius
+                        ((x - (Constants.RegionSize / 2)) * (x - (Constants.RegionSize / 2)) +
+                        (y - (Constants.RegionSize / 2)) * (y - (Constants.RegionSize / 2)));
+                }
+            }
+        }
+        public TerrainChannel(double[,] import)
+        {
+            map = import;
+            taint = new bool[import.GetLength(0), import.GetLength(1)];
+        }
+        public TerrainChannel(bool createMap)
+        {
+            if (createMap)
+            {
+                map = new double[Constants.RegionSize, Constants.RegionSize];
+                taint = new bool[Constants.RegionSize / 16, Constants.RegionSize / 16];
+            }
+        }
+        public TerrainChannel(int w, int h)
+        {
+            map = new double[w, h];
+            taint = new bool[w / 16, h / 16];
+        }
+    }
+}
diff --git a/OpenSim/Region/Environment/Modules/Terrain/TerrainModule.cs b/OpenSim/Region/Environment/Modules/Terrain/TerrainModule.cs
index 83c6658..5931552 100644
--- a/OpenSim/Region/Environment/Modules/Terrain/TerrainModule.cs
+++ b/OpenSim/Region/Environment/Modules/Terrain/TerrainModule.cs
@@ -36,151 +36,18 @@ using OpenSim.Region.Environment.Scenes;
 namespace OpenSim.Region.Environment.Modules.Terrain
 {
-    public interface ITerrainPaintableEffect
+    public class TerrainModule : IRegionModule
-    {
-        void PaintEffect(ITerrainChannel map, double x, double y, double strength, double duration);
-    }
-    public interface ITerrainFloodEffect
-    {
-        void FloodEffect(ITerrainChannel map, Boolean[,] fillArea, double strength);
-    }
-    public interface ITerrainEffect
-    {
-        void RunEffect(ITerrainChannel map, double strength);
-    }
-    public interface ITerrainLoader 
-    {
-        ITerrainChannel LoadFile(string filename);
-        void SaveFile(string filename, ITerrainChannel map);
-    }
-    /// <summary>
-    /// A new version of the old Channel class, simplified
-    /// </summary>
-    public class TerrainChannel : ITerrainChannel
    {
-        private double[,] map;
+        public enum StandardTerrainEffects : byte
-        private bool[,] taint;
-        public int Width
-        {
-            get { return map.GetLength(0); }
-        }
-        public int Height
-        {
-            get { return map.GetLength(1); }
-        }
-        public TerrainChannel Copy()
-        {
-            TerrainChannel copy = new TerrainChannel(false);
-            copy.map = (double[,])this.map.Clone();
-            return copy;
-        }
-        public float[] GetFloatsSerialised()
-        {
-            float[] heights = new float[Width * Height];
-            int i;
-            for (i = 0; i < Width * Height; i++)
-            {
-                heights[i] = (float)map[i % Width, i / Width];
-            }
-            return heights;
-        }
-        public double[,] GetDoubles()
-        {
-            return map;
-        }
-        public double this[int x, int y]
-        {
-            get
-            {
-                return map[x, y];
-            }
-            set
-            {
-                if (map[x, y] != value)
-                {
-                    taint[x / 16, y / 16] = true;
-                    map[x, y] = value;
-                }
-            }
-        }
-        public bool Tainted(int x, int y)
        {
-            if (taint[x / 16, y / 16] != false)
+            Flatten = 0,
-            {
+            Raise = 1,
-                taint[x / 16, y / 16] = false;
+            Lower = 2,
-                return true;
+            Smooth = 3,
-            }
+            Noise = 4,
-            else
+            Revert = 5
-            {
-                return false;
-            }
        }
-        public TerrainChannel()
-        {
-            map = new double[Constants.RegionSize, Constants.RegionSize];
-            taint = new bool[Constants.RegionSize / 16, Constants.RegionSize / 16];
-            int x, y;
-            for (x = 0; x < Constants.RegionSize; x++)
-            {
-                for (y = 0; y < Constants.RegionSize; y++)
-                {
-                    map[x, y] = 60.0 - // 60 = Sphere Radius
-                        ((x - (Constants.RegionSize / 2)) * (x - (Constants.RegionSize / 2)) +
-                        (y - (Constants.RegionSize / 2)) * (y - (Constants.RegionSize / 2)));
-                }
-            }
-        }
-        public TerrainChannel(double[,] import)
-        {
-            map = import;
-            taint = new bool[import.GetLength(0), import.GetLength(1)];
-        }
-        public TerrainChannel(bool createMap)
-        {
-            if (createMap)
-            {
-                map = new double[Constants.RegionSize, Constants.RegionSize];
-                taint = new bool[Constants.RegionSize / 16, Constants.RegionSize / 16];
-            }
-        }
-        public TerrainChannel(int w, int h)
-        {
-            map = new double[w, h];
-            taint = new bool[w / 16, h / 16];
-        }
-    }
-    public enum StandardTerrainEffects : byte
-    {
-        Flatten = 0,
-        Raise = 1,
-        Lower = 2,
-        Smooth = 3,
-        Noise = 4,
-        Revert = 5
-    }
-    public class TerrainModule : IRegionModule
-    {
        private static readonly log4net.ILog m_log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
        private Dictionary<StandardTerrainEffects, ITerrainPaintableEffect> m_painteffects =
diff --git a/OpenSim/Region/Environment/Modules/Terrain/TerrainUtil.cs b/OpenSim/Region/Environment/Modules/Terrain/TerrainUtil.cs
index 23ab321..55265d9 100644
--- a/OpenSim/Region/Environment/Modules/Terrain/TerrainUtil.cs
+++ b/OpenSim/Region/Environment/Modules/Terrain/TerrainUtil.cs
@@ -47,5 +47,60 @@ namespace OpenSim.Region.Environment.Modules.Terrain
            double hi = a00 + (a10 * partialx) + (a01 * partialz) + (a11 * partialx * partialz);
            return hi;
        }
+        private static double Noise(double x, double y)
+        {
+            int n = (int)x + (int)(y * 749);
+            n = (n << 13) ^ n;
+            return (1.0 - ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0);
+        }
+        private static double SmoothedNoise1(double x, double y)
+        {
+            double corners = (Noise(x - 1, y - 1) + Noise(x + 1, y - 1) + Noise(x - 1, y + 1) + Noise(x + 1, y + 1)) / 16;
+            double sides = (Noise(x - 1, y) + Noise(x + 1, y) + Noise(x, y - 1) + Noise(x, y + 1)) / 8;
+            double center = Noise(x, y) / 4;
+            return corners + sides + center;
+        }
+        private static double Interpolate(double x, double y, double z)
+        {
+            return (x * (1.0 - z)) + (y * z);
+        }
+        private static double InterpolatedNoise(double x, double y)
+        {
+            int integer_X = (int)(x);
+            double fractional_X = x - integer_X;
+            int integer_Y = (int)y;
+            double fractional_Y = y - integer_Y;
+            double v1 = SmoothedNoise1(integer_X, integer_Y);
+            double v2 = SmoothedNoise1(integer_X + 1, integer_Y);
+            double v3 = SmoothedNoise1(integer_X, integer_Y + 1);
+            double v4 = SmoothedNoise1(integer_X + 1, integer_Y + 1);
+            double i1 = Interpolate(v1, v2, fractional_X);
+            double i2 = Interpolate(v3, v4, fractional_X);
+            return Interpolate(i1, i2, fractional_Y);
+        }
+        public static double PerlinNoise2D(double x, double y, int octaves, double persistence)
+        {
+            double frequency = 0.0;
+            double amplitude = 0.0;
+            double total = 0.0;
+            for (int i = 0; i < octaves; i++)
+            {
+                frequency = System.Math.Pow(2, i);
+                amplitude = System.Math.Pow(persistence, i);
+                total += InterpolatedNoise(x * frequency, y * frequency) * amplitude;
+            }
+            return total;
+        }
    }
 }