work on navigation

src/Poe2Trade.Navigation/DesktopDuplication.cs

@@ -0,0 +1,148 @@
+using System.Runtime.InteropServices;
+using OpenCvSharp;
+using Serilog;
+using SharpGen.Runtime;
+using Vortice.Direct3D;
+using Vortice.Direct3D11;
+using Vortice.DXGI;
+using Region = Poe2Trade.Core.Region;
+
+namespace Poe2Trade.Navigation;
+
+public sealed class DesktopDuplication : IScreenCapture
+{
+    private readonly ID3D11Device _device;
+    private readonly ID3D11DeviceContext _context;
+    private IDXGIOutputDuplication? _duplication;
+    private ID3D11Texture2D? _staging;
+    private int _stagingW, _stagingH;
+    private bool _needsRecreate;
+
+    public DesktopDuplication()
+    {
+        D3D11.D3D11CreateDevice(
+            null,
+            DriverType.Hardware,
+            DeviceCreationFlags.BgraSupport,
+            [FeatureLevel.Level_11_0],
+            out _device!,
+            out _context!).CheckError();
+
+        CreateDuplication();
+    }
+
+    private void CreateDuplication()
+    {
+        using var dxgiDevice = _device.QueryInterface<IDXGIDevice>();
+        using var adapter = dxgiDevice.GetAdapter();
+        adapter.EnumOutputs(0, out var output);
+        using var _ = output;
+        using var output1 = output.QueryInterface<IDXGIOutput1>();
+        _duplication = output1.DuplicateOutput(_device);
+        _needsRecreate = false;
+        Log.Debug("DXGI Desktop Duplication created");
+    }
+
+    public unsafe Mat? CaptureRegion(Region region)
+    {
+        if (_duplication == null) return null;
+
+        if (_needsRecreate)
+        {
+            try
+            {
+                _duplication.Dispose();
+                CreateDuplication();
+            }
+            catch (Exception ex)
+            {
+                Log.Warning(ex, "Failed to recreate DXGI duplication");
+                return null;
+            }
+        }
+
+        IDXGIResource? resource = null;
+        try
+        {
+            _duplication.AcquireNextFrame(100, out _, out resource);
+        }
+        catch (SharpGenException ex)
+        {
+            if (ex.ResultCode == Vortice.DXGI.ResultCode.AccessLost)
+                _needsRecreate = true;
+            // WaitTimeout is normal when screen hasn't changed
+            return null;
+        }
+
+        try
+        {
+            using var srcTexture = resource!.QueryInterface<ID3D11Texture2D>();
+            EnsureStaging(region.Width, region.Height);
+
+            // Copy only the region we need from the desktop texture
+            _context.CopySubresourceRegion(
+                _staging!, 0, 0, 0, 0,
+                srcTexture, 0,
+                new Vortice.Mathematics.Box(region.X, region.Y, 0,
+                    region.X + region.Width, region.Y + region.Height, 1));
+
+            var mapped = _context.Map(_staging!, 0, MapMode.Read);
+            try
+            {
+                var mat = new Mat(region.Height, region.Width, MatType.CV_8UC4);
+                var rowBytes = region.Width * 4;
+
+                for (var row = 0; row < region.Height; row++)
+                {
+                    Buffer.MemoryCopy(
+                        (void*)(mapped.DataPointer + row * mapped.RowPitch),
+                        (void*)mat.Ptr(row),
+                        rowBytes, rowBytes);
+                }
+
+                // BGRA → BGR
+                var bgr = new Mat();
+                Cv2.CvtColor(mat, bgr, ColorConversionCodes.BGRA2BGR);
+                mat.Dispose();
+                return bgr;
+            }
+            finally
+            {
+                _context.Unmap(_staging!, 0);
+            }
+        }
+        finally
+        {
+            resource?.Dispose();
+            _duplication!.ReleaseFrame();
+        }
+    }
+
+    private void EnsureStaging(int w, int h)
+    {
+        if (_staging != null && _stagingW == w && _stagingH == h) return;
+        _staging?.Dispose();
+
+        _staging = _device.CreateTexture2D(new Texture2DDescription
+        {
+            Width = (uint)w,
+            Height = (uint)h,
+            MipLevels = 1,
+            ArraySize = 1,
+            Format = Format.B8G8R8A8_UNorm,
+            SampleDescription = new SampleDescription(1, 0),
+            Usage = ResourceUsage.Staging,
+            CPUAccessFlags = CpuAccessFlags.Read,
+        });
+        _stagingW = w;
+        _stagingH = h;
+    }
+
+    public void Dispose()
+    {
+        _staging?.Dispose();
+        _duplication?.Dispose();
+        _context?.Dispose();
+        _device?.Dispose();
+    }
+}