1 files changed, 85 insertions, 0 deletions
diff --git a/Ryujinx.Graphics.Nvdec.Vp9/Types/TileInfo.cs b/Ryujinx.Graphics.Nvdec.Vp9/Types/TileInfo.cs
new file mode 100644
index 00000000..67289c47
--- /dev/null
+++ b/Ryujinx.Graphics.Nvdec.Vp9/Types/TileInfo.cs
@@ -0,0 +1,85 @@
+using Ryujinx.Graphics.Nvdec.Vp9.Common;
+using System;
+using System.Diagnostics;
+
+namespace Ryujinx.Graphics.Nvdec.Vp9.Types
+{
+    internal struct TileInfo
+    {
+        private const int MinTileWidthB64 = 4;
+        private const int MaxTileWidthB64 = 64;
+
+        public int MiRowStart, MiRowEnd;
+        public int MiColStart, MiColEnd;
+
+        public static int MiColsAlignedToSb(int nMis)
+        {
+            return BitUtils.AlignPowerOfTwo(nMis, Constants.MiBlockSizeLog2);
+        }
+
+        private static int GetTileOffset(int idx, int mis, int log2)
+        {
+            int sbCols = MiColsAlignedToSb(mis) >> Constants.MiBlockSizeLog2;
+            int offset = ((idx * sbCols) >> log2) << Constants.MiBlockSizeLog2;
+            return Math.Min(offset, mis);
+        }
+
+        public void SetRow(ref Vp9Common cm, int row)
+        {
+            MiRowStart = GetTileOffset(row, cm.MiRows, cm.Log2TileRows);
+            MiRowEnd = GetTileOffset(row + 1, cm.MiRows, cm.Log2TileRows);
+        }
+
+        public void SetCol(ref Vp9Common cm, int col)
+        {
+            MiColStart = GetTileOffset(col, cm.MiCols, cm.Log2TileCols);
+            MiColEnd = GetTileOffset(col + 1, cm.MiCols, cm.Log2TileCols);
+        }
+
+        public void Init(ref Vp9Common cm, int row, int col)
+        {
+            SetRow(ref cm, row);
+            SetCol(ref cm, col);
+        }
+
+        // Checks that the given miRow, miCol and search point
+        // are inside the borders of the tile.
+        public bool IsInside(int miCol, int miRow, int miRows, ref Position miPos)
+        {
+            return !(miRow + miPos.Row < 0 ||
+                     miCol + miPos.Col < MiColStart ||
+                     miRow + miPos.Row >= miRows ||
+                     miCol + miPos.Col >= MiColEnd);
+        }
+
+        private static int GetMinLog2TileCols(int sb64Cols)
+        {
+            int minLog2 = 0;
+            while ((MaxTileWidthB64 << minLog2) < sb64Cols)
+            {
+                ++minLog2;
+            }
+
+            return minLog2;
+        }
+
+        private static int GetMaxLog2TileCols(int sb64Cols)
+        {
+            int maxLog2 = 1;
+            while ((sb64Cols >> maxLog2) >= MinTileWidthB64)
+            {
+                ++maxLog2;
+            }
+
+            return maxLog2 - 1;
+        }
+
+        public static void GetTileNBits(int miCols, ref int minLog2TileCols, ref int maxLog2TileCols)
+        {
+            int sb64Cols = MiColsAlignedToSb(miCols) >> Constants.MiBlockSizeLog2;
+            minLog2TileCols = GetMinLog2TileCols(sb64Cols);
+            maxLog2TileCols = GetMaxLog2TileCols(sb64Cols);
+            Debug.Assert(minLog2TileCols <= maxLog2TileCols);
+        }
+    }
+}