feat(ui): render DXF text annotations in CAD converter preview

Extract MText and TextEntity from the CadDocument during DXF import
and render them in the EntityView. Handles text alignment (left/center/
right via InsertPoint vs AlignmentPoint) and replaces AutoCAD control
codes (%%p → ±, %%d → °, %%c → ⌀). MText formatting codes are
stripped before display.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

OpenNest.Console/Program.cs

@@ -151,7 +151,8 @@ static class NestConsole
             f.EndsWith(NestFormat.FileExtension, StringComparison.OrdinalIgnoreCase)
             || f.EndsWith(".zip", StringComparison.OrdinalIgnoreCase));
         var dxfFiles = options.InputFiles.Where(f =>
-            f.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase)).ToList();
+            f.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase) ||
+            f.EndsWith(".dwg", StringComparison.OrdinalIgnoreCase)).ToList();
 
         // If we have a nest file, load it and optionally add DXFs.
         if (nestFile != null)
@@ -187,7 +188,7 @@ static class NestConsole
         // DXF-only mode: create a fresh nest.
         if (dxfFiles.Count == 0)
         {
-            Console.Error.WriteLine("Error: no nest (.nest) or DXF (.dxf) files specified");
+            Console.Error.WriteLine("Error: no nest (.nest) or CAD (.dxf/.dwg) files specified");
             return null;
         }
 
@@ -461,7 +462,7 @@ static class NestConsole
         Console.Error.WriteLine("Usage: OpenNest.Console <input-files...> [options]");
         Console.Error.WriteLine();
         Console.Error.WriteLine("Arguments:");
-        Console.Error.WriteLine("  input-files            One or more .nest nest files or .dxf drawing files");
+        Console.Error.WriteLine("  input-files            One or more .nest nest files or .dxf/.dwg drawing files");
         Console.Error.WriteLine();
         Console.Error.WriteLine("Modes:");
         Console.Error.WriteLine("  <nest.nest>             Load nest and fill (existing behavior)");

OpenNest.IO/Bom/BomAnalyzer.cs

@@ -42,6 +42,11 @@ namespace OpenNest.IO.Bom
                     var nameWithoutExt = Path.GetFileNameWithoutExtension(file);
                     dxfFiles[nameWithoutExt] = file;
                 }
+                foreach (var file in Directory.GetFiles(dxfFolder, "*.dwg"))
+                {
+                    var nameWithoutExt = Path.GetFileNameWithoutExtension(file);
+                    dxfFiles.TryAdd(nameWithoutExt, file);
+                }
             }
 
             // Partition items into: skipped, unmatched, or matched (grouped)
@@ -57,8 +62,8 @@ namespace OpenNest.IO.Bom
 
                 var lookupName = item.FileName;
 
-                // Strip .dxf extension if the BOM includes it
-                if (lookupName.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase))
+                if (lookupName.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase)
+                    || lookupName.EndsWith(".dwg", StringComparison.OrdinalIgnoreCase))
                     lookupName = Path.GetFileNameWithoutExtension(lookupName);
 
                 if (!folderExists)

OpenNest.IO/CadImportResult.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using ACadSharp;
 using OpenNest.Bending;
 using OpenNest.Geometry;
 
@@ -38,5 +39,11 @@ namespace OpenNest.IO
         /// Default drawing name (filename without extension, unless overridden).
         /// </summary>
         public string Name { get; set; }
+
+        /// <summary>
+        /// The raw CAD document from the source file. Available for callers
+        /// that need access to non-geometry entities (e.g., text annotations).
+        /// </summary>
+        public CadDocument Document { get; set; }
     }
 }

OpenNest.IO/CadImporter.cs

@@ -47,6 +47,7 @@ namespace OpenNest.IO
                 Bounds = dxf.Entities.GetBoundingBox(),
                 SourcePath = path,
                 Name = options.Name ?? Path.GetFileNameWithoutExtension(path),
+                Document = dxf.Document,
             };
         }
 

OpenNest.IO/Dxf.cs

@@ -27,8 +27,7 @@ namespace OpenNest.IO
         /// </summary>
         public static DxfImportResult Import(string path)
         {
-            using var reader = new DxfReader(path);
-            var doc = reader.Read();
+            var doc = ReadDocument(path);
 
             return new DxfImportResult
             {
@@ -41,8 +40,7 @@ namespace OpenNest.IO
         {
             try
             {
-                using var reader = new DxfReader(path);
-                var doc = reader.Read();
+                var doc = ReadDocument(path);
                 return ConvertEntities(doc);
             }
             catch (Exception ex)
@@ -113,6 +111,23 @@ namespace OpenNest.IO
 
         #region Private
 
+        private static bool IsDwg(string path) =>
+            Path.GetExtension(path).Equals(".dwg", StringComparison.OrdinalIgnoreCase);
+
+        private static CadDocument ReadDocument(string path)
+        {
+            if (IsDwg(path))
+            {
+                using var reader = new DwgReader(path);
+                return reader.Read();
+            }
+            else
+            {
+                using var reader = new DxfReader(path);
+                return reader.Read();
+            }
+        }
+
         private static List<Entity> ConvertEntities(CadDocument doc)
         {
             var entities = new List<Entity>();

OpenNest.Training/Program.cs

@@ -89,8 +89,10 @@ int RunDataCollection(string dir, string dbPath, string saveDir, double s, strin
         new Size(48, 24), new Size(120, 10)
     };
 
-    var dxfFiles = Directory.GetFiles(dir, "*.dxf", SearchOption.AllDirectories);
-    Console.WriteLine($"Found {dxfFiles.Length} DXF files");
+    var dxfFiles = Directory.GetFiles(dir, "*.dxf", SearchOption.AllDirectories)
+        .Concat(Directory.GetFiles(dir, "*.dwg", SearchOption.AllDirectories))
+        .ToArray();
+    Console.WriteLine($"Found {dxfFiles.Length} CAD files");
     var resolvedDb = dbPath.EndsWith(".db", StringComparison.OrdinalIgnoreCase) ? dbPath : dbPath + ".db";
     Console.WriteLine($"Database: {Path.GetFullPath(resolvedDb)}");
     Console.WriteLine($"Sheet sizes: {sheetSuite.Length} configurations");

OpenNest/Controls/CadText.cs

@@ -0,0 +1,16 @@
+using System.Drawing;
+using OpenNest.Geometry;
+
+namespace OpenNest.Controls
+{
+    public class CadText
+    {
+        public Vector Position { get; set; }
+        public string Value { get; set; }
+        public double Height { get; set; }
+        public double Rotation { get; set; }
+        public string LayerName { get; set; }
+        public StringAlignment HAlign { get; set; }
+        public StringAlignment VAlign { get; set; }
+    }
+}

OpenNest/Controls/EntityView.cs

@@ -29,12 +29,14 @@ namespace OpenNest.Controls
         public List<Entity> SimplifierToleranceRight { get; set; }
         public List<Entity> OriginalEntities { get; set; }
         public bool ShowEntityLabels { get; set; }
+        public List<CadText> Texts { get; set; } = new List<CadText>();
 
         private readonly Pen gridPen = new Pen(Color.FromArgb(70, 70, 70));
         private readonly Dictionary<int, Pen> penCache = new Dictionary<int, Pen>();
         private readonly Font labelFont = new Font("Segoe UI", 7f);
         private readonly SolidBrush labelBrush = new SolidBrush(Color.FromArgb(220, 255, 255, 200));
         private readonly SolidBrush labelBackBrush = new SolidBrush(Color.FromArgb(33, 40, 48));
+        private readonly SolidBrush textBrush = new SolidBrush(Color.FromArgb(180, 200, 200, 200));
 
         public event EventHandler<Line> LinePicked;
         public event EventHandler PickCancelled;
@@ -116,6 +118,8 @@ namespace OpenNest.Controls
                 DrawEntity(e.Graphics, entity, pen);
             }
 
+            DrawTexts(e.Graphics);
+
             if (ShowEntityLabels)
                 DrawEntityLabels(e.Graphics);
 
@@ -408,6 +412,7 @@ namespace OpenNest.Controls
                 labelFont.Dispose();
                 labelBrush.Dispose();
                 labelBackBrush.Dispose();
+                textBrush.Dispose();
             }
             base.Dispose(disposing);
         }
@@ -474,6 +479,34 @@ namespace OpenNest.Controls
                 diameter);
         }
 
+        private void DrawTexts(Graphics g)
+        {
+            if (Texts == null || Texts.Count == 0)
+                return;
+
+            using var sf = new StringFormat();
+
+            foreach (var text in Texts)
+            {
+                var pos = PointWorldToGraph(text.Position);
+                var fontSize = LengthWorldToGui(text.Height);
+                if (fontSize < 2f) continue;
+
+                var state = g.Save();
+                g.TranslateTransform(pos.X, pos.Y);
+
+                if (text.Rotation != 0)
+                    g.RotateTransform((float)OpenNest.Math.Angle.ToDegrees(text.Rotation));
+
+                sf.Alignment = text.HAlign;
+                sf.LineAlignment = text.VAlign;
+
+                using var font = new Font("Segoe UI", fontSize, GraphicsUnit.Pixel);
+                g.DrawString(text.Value, font, textBrush, 0, 0, sf);
+                g.Restore(state);
+            }
+        }
+
         private void DrawPoint(Graphics g, Vector pt, Pen pen)
         {
             var pt1 = PointWorldToGraph(pt);

OpenNest/Controls/FileListControl.cs

@@ -22,6 +22,7 @@ namespace OpenNest.Controls
         public HashSet<Guid> SuppressedEntityIds { get; set; }
         public Box Bounds { get; set; }
         public int EntityCount { get; set; }
+        public List<CadText> Texts { get; set; } = new();
     }
 
     public class FileListControl : Control

OpenNest/Forms/BomImportForm.cs

@@ -165,7 +165,8 @@ namespace OpenNest.Forms
                 else
                 {
                     var lookupName = item.FileName;
-                    if (lookupName.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase))
+                    if (lookupName.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase)
+                        || lookupName.EndsWith(".dwg", StringComparison.OrdinalIgnoreCase))
                         lookupName = Path.GetFileNameWithoutExtension(lookupName);
 
                     if (matchedPaths.TryGetValue(lookupName, out var dxfPath))

OpenNest/Forms/CadConverterForm.cs

@@ -92,7 +92,8 @@ namespace OpenNest.Forms
                     Customer = string.Empty,
                     Bends = result.Bends,
                     Bounds = result.Bounds,
-                    EntityCount = result.Entities.Count
+                    EntityCount = result.Entities.Count,
+                    Texts = ExtractTexts(result.Document),
                 };
 
                 if (InvokeRequired)
@@ -152,6 +153,7 @@ namespace OpenNest.Forms
             entityView1.Entities.Clear();
             entityView1.Entities.AddRange(item.Entities);
             entityView1.Bends = item.Bends ?? new List<Bend>();
+            entityView1.Texts = item.Texts ?? new List<CadText>();
 
             item.Entities.ForEach(e => e.IsVisible = true);
             if (item.Entities.Any(e => e.Layer != null))
@@ -473,7 +475,8 @@ namespace OpenNest.Forms
             {
                 var files = (string[])e.Data.GetData(DataFormats.FileDrop);
                 var dxfFiles = files.Where(f =>
-                    f.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase)).ToArray();
+                    f.EndsWith(".dxf", StringComparison.OrdinalIgnoreCase) ||
+                    f.EndsWith(".dwg", StringComparison.OrdinalIgnoreCase)).ToArray();
                 if (dxfFiles.Length > 0)
                     AddFiles(dxfFiles);
             }
@@ -803,6 +806,102 @@ namespace OpenNest.Forms
 
         #endregion
 
+        private static List<CadText> ExtractTexts(ACadSharp.CadDocument doc)
+        {
+            var texts = new List<CadText>();
+            if (doc == null) return texts;
+
+            foreach (var entity in doc.Entities)
+            {
+                switch (entity)
+                {
+                    case ACadSharp.Entities.MText mtext:
+                        var (mh, mv) = MapAttachmentPoint(mtext.AttachmentPoint);
+                        texts.Add(new CadText
+                        {
+                            Position = new Vector(mtext.InsertPoint.X, mtext.InsertPoint.Y),
+                            Value = ReplaceControlCodes(StripMTextFormatting(mtext.Value)),
+                            Height = mtext.Height,
+                            Rotation = mtext.Rotation,
+                            LayerName = mtext.Layer?.Name,
+                            HAlign = mh,
+                            VAlign = mv,
+                        });
+                        break;
+
+                    case ACadSharp.Entities.TextEntity text:
+                        var useAlignment = text.HorizontalAlignment != 0
+                            || text.VerticalAlignment != 0;
+                        var pt = useAlignment ? text.AlignmentPoint : text.InsertPoint;
+                        var ha = text.HorizontalAlignment switch
+                        {
+                            ACadSharp.Entities.TextHorizontalAlignment.Center => System.Drawing.StringAlignment.Center,
+                            ACadSharp.Entities.TextHorizontalAlignment.Right => System.Drawing.StringAlignment.Far,
+                            _ => System.Drawing.StringAlignment.Near,
+                        };
+                        texts.Add(new CadText
+                        {
+                            Position = new Vector(pt.X, pt.Y),
+                            Value = ReplaceControlCodes(text.Value),
+                            Height = text.Height,
+                            Rotation = text.Rotation,
+                            LayerName = text.Layer?.Name,
+                            HAlign = ha,
+                        });
+                        break;
+                }
+            }
+
+            return texts;
+        }
+
+        private static (System.Drawing.StringAlignment h, System.Drawing.StringAlignment v) MapAttachmentPoint(
+            ACadSharp.Entities.AttachmentPointType apt)
+        {
+            var h = apt switch
+            {
+                ACadSharp.Entities.AttachmentPointType.TopCenter
+                    or ACadSharp.Entities.AttachmentPointType.MiddleCenter
+                    or ACadSharp.Entities.AttachmentPointType.BottomCenter => System.Drawing.StringAlignment.Center,
+                ACadSharp.Entities.AttachmentPointType.TopRight
+                    or ACadSharp.Entities.AttachmentPointType.MiddleRight
+                    or ACadSharp.Entities.AttachmentPointType.BottomRight => System.Drawing.StringAlignment.Far,
+                _ => System.Drawing.StringAlignment.Near,
+            };
+            var v = apt switch
+            {
+                ACadSharp.Entities.AttachmentPointType.MiddleLeft
+                    or ACadSharp.Entities.AttachmentPointType.MiddleCenter
+                    or ACadSharp.Entities.AttachmentPointType.MiddleRight => System.Drawing.StringAlignment.Center,
+                ACadSharp.Entities.AttachmentPointType.BottomLeft
+                    or ACadSharp.Entities.AttachmentPointType.BottomCenter
+                    or ACadSharp.Entities.AttachmentPointType.BottomRight => System.Drawing.StringAlignment.Far,
+                _ => System.Drawing.StringAlignment.Near,
+            };
+            return (h, v);
+        }
+
+        private static string StripMTextFormatting(string text)
+        {
+            if (string.IsNullOrEmpty(text)) return text;
+            var result = System.Text.RegularExpressions.Regex.Replace(text, @"\\[A-Za-z][^;]*;", "");
+            result = result.Replace("{", "").Replace("}", "");
+            return result.Trim();
+        }
+
+        private static string ReplaceControlCodes(string text)
+        {
+            if (string.IsNullOrEmpty(text)) return text;
+            return text
+                .Replace("%%p", "±")
+                .Replace("%%P", "±")
+                .Replace("%%d", "°")
+                .Replace("%%D", "°")
+                .Replace("%%c", "⌀")
+                .Replace("%%C", "⌀")
+                .Replace("%%%", "%");
+        }
+
         private void filterPanel_Paint(object sender, PaintEventArgs e)
         {
 

OpenNest/Forms/EditNestForm.cs

@@ -329,7 +329,7 @@ namespace OpenNest.Forms
         {
             var dlg = new OpenFileDialog();
             dlg.Multiselect = true;
-            dlg.Filter = "DXF Files (*.dxf) | *.dxf";
+            dlg.Filter = "CAD Files (*.dxf;*.dwg)|*.dxf;*.dwg|DXF Files (*.dxf)|*.dxf|DWG Files (*.dwg)|*.dwg";
 
             if (dlg.ShowDialog() != DialogResult.OK)
                 return;
@@ -346,7 +346,6 @@ namespace OpenNest.Forms
             drawings.ForEach(d => Nest.Drawings.Add(d));
 
             UpdateDrawingList();
-            tabControl1.SelectedIndex = 1;
         }
 
         public bool Export()