1 files changed, 121 insertions, 0 deletions
diff --git a/Ryujinx.Graphics.Texture/Astc/BitArrayStream.cs b/Ryujinx.Graphics.Texture/Astc/BitArrayStream.cs
new file mode 100644
index 00000000..3c472a3c
--- /dev/null
+++ b/Ryujinx.Graphics.Texture/Astc/BitArrayStream.cs
@@ -0,0 +1,121 @@
+using System;
+using System.Collections;
+
+namespace Ryujinx.Graphics.Texture.Astc
+{
+    public class BitArrayStream
+    {
+        public BitArray BitsArray;
+
+        public int Position { get; private set; }
+
+        public BitArrayStream(BitArray bitArray)
+        {
+            BitsArray = bitArray;
+            Position  = 0;
+        }
+
+        public short ReadBits(int length)
+        {
+            int retValue = 0;
+            for (int i = Position; i < Position + length; i++)
+            {
+                if (BitsArray[i])
+                {
+                    retValue |= 1 << (i - Position);
+                }
+            }
+
+            Position += length;
+            return (short)retValue;
+        }
+
+        public int ReadBits(int start, int end)
+        {
+            int retValue = 0;
+            for (int i = start; i <= end; i++)
+            {
+                if (BitsArray[i])
+                {
+                    retValue |= 1 << (i - start);
+                }
+            }
+
+            return retValue;
+        }
+
+        public int ReadBit(int index)
+        {
+            return Convert.ToInt32(BitsArray[index]);
+        }
+
+        public void WriteBits(int value, int length)
+        {
+            for (int i = Position; i < Position + length; i++)
+            {
+                BitsArray[i] = ((value >> (i - Position)) & 1) != 0;
+            }
+
+            Position += length;
+        }
+
+        public byte[] ToByteArray()
+        {
+            byte[] retArray = new byte[(BitsArray.Length + 7) / 8];
+            BitsArray.CopyTo(retArray, 0);
+            return retArray;
+        }
+
+        public static int Replicate(int value, int numberBits, int toBit)
+        {
+            if (numberBits == 0) return 0;
+            if (toBit == 0) return 0;
+
+            int tempValue = value & ((1 << numberBits) - 1);
+            int retValue  = tempValue;
+            int resLength = numberBits;
+
+            while (resLength < toBit)
+            {
+                int comp = 0;
+                if (numberBits > toBit - resLength)
+                {
+                    int newShift = toBit - resLength;
+                    comp         = numberBits - newShift;
+                    numberBits   = newShift;
+                }
+                retValue <<= numberBits;
+                retValue  |= tempValue >> comp;
+                resLength += numberBits;
+            }
+            return retValue;
+        }
+
+        public static int PopCnt(int number)
+        {
+            int counter;
+            for (counter = 0; number != 0; counter++)
+            {
+                number &= number - 1;
+            }
+            return counter;
+        }
+
+        public static void Swap<T>(ref T lhs, ref T rhs)
+        {
+            T temp = lhs;
+            lhs = rhs;
+            rhs = temp;
+        }
+
+        // Transfers a bit as described in C.2.14
+        public static void BitTransferSigned(ref int a, ref int b)
+        {
+            b >>= 1;
+            b |= a & 0x80;
+            a >>= 1;
+            a &= 0x3F;
+            if ((a & 0x20) != 0) a -= 0x40;
+        }
+    }
+}