NVDEC implementation using FFmpeg (#443)

* Initial nvdec implementation using FFmpeg

* Fix swapped channels on the video decoder and the G8R8 texture format

* Fix texture samplers not being set properly (regression)

* Rebased

* Remove unused code introduced on the rebase

* Add support for RGBA8 output format on the video image composer

* Correct spacing

* Some fixes for rebase and other tweaks

* Allow size mismatch on frame copy

* Get rid of GetHostAddress calls on VDec

1 files changed, 59 insertions, 0 deletions

diff --git a/Ryujinx.Graphics/Graphics3d/Texture/BlockLinearSwizzle.cs b/Ryujinx.Graphics/Graphics3d/Texture/BlockLinearSwizzle.cs
new file mode 100644
index 00000000..9451291e
--- /dev/null
+++ b/Ryujinx.Graphics/Graphics3d/Texture/BlockLinearSwizzle.cs
@@ -0,0 +1,59 @@
+using System;
+
+namespace Ryujinx.Graphics.Texture
+{
+    class BlockLinearSwizzle : ISwizzle
+    {
+        private int BhShift;
+        private int BppShift;
+        private int BhMask;
+
+        private int XShift;
+        private int GobStride;
+
+        public BlockLinearSwizzle(int Width, int Bpp, int BlockHeight = 16)
+        {
+            BhMask = (BlockHeight * 8) - 1;
+
+            BhShift  = CountLsbZeros(BlockHeight * 8);
+            BppShift = CountLsbZeros(Bpp);
+
+            int WidthInGobs = (int)MathF.Ceiling(Width * Bpp / 64f);
+
+            GobStride = 512 * BlockHeight * WidthInGobs;
+
+            XShift = CountLsbZeros(512 * BlockHeight);
+        }
+
+        private int CountLsbZeros(int Value)
+        {
+            int Count = 0;
+
+            while (((Value >> Count) & 1) == 0)
+            {
+                Count++;
+            }
+
+            return Count;
+        }
+
+        public int GetSwizzleOffset(int X, int Y)
+        {
+            X <<= BppShift;
+
+            int Position = (Y >> BhShift) * GobStride;
+
+            Position += (X >> 6) << XShift;
+
+            Position += ((Y & BhMask) >> 3) << 9;
+
+            Position += ((X & 0x3f) >> 5) << 8;
+            Position += ((Y & 0x07) >> 1) << 6;
+            Position += ((X & 0x1f) >> 4) << 5;
+            Position += ((Y & 0x01) >> 0) << 4;
+            Position += ((X & 0x0f) >> 0) << 0;
+
+            return Position;
+        }
+    }
+}
\ No newline at end of file