llListRandomize() wasn't very random

Signed-off-by: Diva Canto <diva@metaverseink.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/OpenSim/Framework/Util.cs b/OpenSim/Framework/Util.cs
index 56a90b1..2d0b280 100644
--- a/OpenSim/Framework/Util.cs
+++ b/OpenSim/Framework/Util.cs
@@ -3036,4 +3036,55 @@ namespace OpenSim.Framework
             }
         }
     }
+
+    public class BetterRandom
+    {
+        private const int BufferSize = 1024;  // must be a multiple of 4
+        private byte[] RandomBuffer;
+        private int BufferOffset;
+        private RNGCryptoServiceProvider rng;
+        public BetterRandom()
+        {
+            RandomBuffer = new byte[BufferSize];
+            rng = new RNGCryptoServiceProvider();
+            BufferOffset = RandomBuffer.Length;
+        }
+        private void FillBuffer()
+        {
+            rng.GetBytes(RandomBuffer);
+            BufferOffset = 0;
+        }
+        public int Next()
+        {
+            if (BufferOffset >= RandomBuffer.Length)
+            {
+                FillBuffer();
+            }
+            int val = BitConverter.ToInt32(RandomBuffer, BufferOffset) & 0x7fffffff;
+            BufferOffset += sizeof(int);
+            return val;
+        }
+        public int Next(int maxValue)
+        {
+            return Next() % maxValue;
+        }
+        public int Next(int minValue, int maxValue)
+        {
+            if (maxValue < minValue)
+            {
+                throw new ArgumentOutOfRangeException("maxValue must be greater than or equal to minValue");
+            }
+            int range = maxValue - minValue;
+            return minValue + Next(range);
+        }
+        public double NextDouble()
+        {
+            int val = Next();
+            return (double)val / int.MaxValue;
+        }
+        public void GetBytes(byte[] buff)
+        {
+            rng.GetBytes(buff);
+        }
+    }
 }