1 files changed, 138 insertions, 0 deletions
diff --git a/Ryujinx.Graphics/Texture/ASTCPixel.cs b/Ryujinx.Graphics/Texture/ASTCPixel.cs
new file mode 100644
index 00000000..c43eaf93
--- /dev/null
+++ b/Ryujinx.Graphics/Texture/ASTCPixel.cs
@@ -0,0 +1,138 @@
+using System;
+using System.Diagnostics;
+
+namespace Ryujinx.Graphics.Texture
+{
+    class ASTCPixel
+    {
+        public short R { get; set; }
+        public short G { get; set; }
+        public short B { get; set; }
+        public short A { get; set; }
+
+        byte[] BitDepth = new byte[4];
+
+        public ASTCPixel(short _A, short _R, short _G, short _B)
+        {
+            A = _A;
+            R = _R;
+            G = _G;
+            B = _B;
+
+            for (int i = 0; i < 4; i++)
+                BitDepth[i] = 8;
+        }
+
+        public void ClampByte()
+        {
+            R = Math.Min(Math.Max(R, (short)0), (short)255);
+            G = Math.Min(Math.Max(G, (short)0), (short)255);
+            B = Math.Min(Math.Max(B, (short)0), (short)255);
+            A = Math.Min(Math.Max(A, (short)0), (short)255);
+        }
+
+        public short GetComponent(int Index)
+        {
+            switch(Index)
+            {
+                case 0: return A;
+                case 1: return R;
+                case 2: return G;
+                case 3: return B;
+            }
+
+            return 0;
+        }
+
+        public void SetComponent(int Index, int Value)
+        {
+            switch (Index)
+            {
+                case 0:
+                    A = (short)Value;
+                    break;
+                case 1:
+                    R = (short)Value;
+                    break;
+                case 2:
+                    G = (short)Value;
+                    break;
+                case 3:
+                    B = (short)Value;
+                    break;
+            }
+        }
+
+        public void ChangeBitDepth(byte[] Depth)
+        {
+            for(int i = 0; i< 4; i++)
+            {
+                int Value = ChangeBitDepth(GetComponent(i), BitDepth[i], Depth[i]);
+
+                SetComponent(i, Value);
+                BitDepth[i] = Depth[i];
+            }
+        }
+
+        short ChangeBitDepth(short Value, byte OldDepth, byte NewDepth)
+        {
+            Debug.Assert(NewDepth <= 8);
+            Debug.Assert(OldDepth <= 8);
+
+            if (OldDepth == NewDepth)
+            {
+                // Do nothing
+                return Value;
+            }
+            else if (OldDepth == 0 && NewDepth != 0)
+            {
+                return (short)((1 << NewDepth) - 1);
+            }
+            else if (NewDepth > OldDepth)
+            {
+                return (short)BitArrayStream.Replicate(Value, OldDepth, NewDepth);
+            }
+            else
+            {
+                // oldDepth > newDepth
+                if (NewDepth == 0)
+                {
+                    return 0xFF;
+                }
+                else
+                {
+                    byte BitsWasted = (byte)(OldDepth - NewDepth);
+                    short TempValue = Value;
+
+                    TempValue = (short)((TempValue + (1 << (BitsWasted - 1))) >> BitsWasted);
+                    TempValue = Math.Min(Math.Max((short)0, TempValue), (short)((1 << NewDepth) - 1));
+
+                    return (byte)(TempValue);
+                }
+            }
+        }
+
+        public int Pack()
+        {
+            ASTCPixel NewPixel   = new ASTCPixel(A, R, G, B);
+            byte[] eightBitDepth = { 8, 8, 8, 8 };
+
+            NewPixel.ChangeBitDepth(eightBitDepth);
+
+            return (byte)NewPixel.A << 24 |
+                   (byte)NewPixel.B << 16 |
+                   (byte)NewPixel.G << 8  |
+                   (byte)NewPixel.R << 0;
+        }
+
+        // Adds more precision to the blue channel as described
+        // in C.2.14
+        public static ASTCPixel BlueContract(int a, int r, int g, int b)
+        {
+            return new ASTCPixel((short)(a),
+                                 (short)((r + b) >> 1),
+                                 (short)((g + b) >> 1),
+                                 (short)(b));
+        }
+    }
+}