Initial work

Ryujinx.Graphics.Texture/OffsetCalculator.cs

@@ -0,0 +1,55 @@
+using Ryujinx.Common;
+
+using static Ryujinx.Graphics.Texture.BlockLinearConstants;
+
+namespace Ryujinx.Graphics.Texture
+{
+    public class OffsetCalculator
+    {
+        private int  _stride;
+        private bool _isLinear;
+        private int  _bytesPerPixel;
+
+        private BlockLinearLayout _layoutConverter;
+
+        public OffsetCalculator(
+            int  width,
+            int  height,
+            int  stride,
+            bool isLinear,
+            int  gobBlocksInY,
+            int  bytesPerPixel)
+        {
+            _stride        = stride;
+            _isLinear      = isLinear;
+            _bytesPerPixel = bytesPerPixel;
+
+            int wAlignment = GobStride / bytesPerPixel;
+
+            int wAligned = BitUtils.AlignUp(width, wAlignment);
+
+            if (!isLinear)
+            {
+                _layoutConverter = new BlockLinearLayout(
+                    wAligned,
+                    height,
+                    1,
+                    gobBlocksInY,
+                    1,
+                    bytesPerPixel);
+            }
+        }
+
+        public int GetOffset(int x, int y)
+        {
+            if (_isLinear)
+            {
+                return x * _bytesPerPixel + y * _stride;
+            }
+            else
+            {
+                return _layoutConverter.GetOffset(x, y, 0);
+            }
+        }
+    }
+}