fix: improve CadConverter sidebar layout and bend line visibility

Replace sidebar Panel+Splitter with SplitContainer for resizable file
list / filter panel. Sort file list alphabetically on insert. Widen bend
line dash spacing and draw ETCH layer entities on top of bend lines so
etch marks are visible.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

OpenNest.IO/DxfImporter.cs

@@ -24,6 +24,11 @@ namespace OpenNest.IO
 
             foreach (var entity in doc.Entities)
             {
+                // Skip bend line entities — they are converted to Bend objects
+                // separately via bend detection, not cut geometry.
+                if (IsBendLayer(entity.Layer?.Name))
+                    continue;
+
                 switch (entity)
                 {
                     case ACadSharp.Entities.Line line:
@@ -131,5 +136,10 @@ namespace OpenNest.IO
 
             return success;
         }
+
+        private static bool IsBendLayer(string layerName)
+        {
+            return string.Equals(layerName, "BEND", System.StringComparison.OrdinalIgnoreCase);
+        }
     }
 }

OpenNest/Controls/EntityView.cs

@@ -48,12 +48,20 @@ namespace OpenNest.Controls
 
             foreach (var entity in Entities)
             {
+                if (IsEtchLayer(entity.Layer)) continue;
                 var pen = GetEntityPen(entity.Color);
                 DrawEntity(e.Graphics, entity, pen);
             }
 
             DrawBendLines(e.Graphics);
 
+            foreach (var entity in Entities)
+            {
+                if (!IsEtchLayer(entity.Layer)) continue;
+                var pen = GetEntityPen(entity.Color);
+                DrawEntity(e.Graphics, entity, pen);
+            }
+
 #if DRAW_OFFSET
 
             var offsetShape = new Shape();
@@ -138,6 +146,9 @@ namespace OpenNest.Controls
             penCache.Clear();
         }
 
+        private static bool IsEtchLayer(Layer layer) =>
+            string.Equals(layer?.Name, "ETCH", System.StringComparison.OrdinalIgnoreCase);
+
         private void DrawBendLines(Graphics g)
         {
             if (Bends == null || Bends.Count == 0)
@@ -145,11 +156,11 @@ namespace OpenNest.Controls
 
             using var bendPen = new Pen(Color.Yellow, 1.5f)
             {
-                DashStyle = DashStyle.Dash
+                DashPattern = new float[] { 8, 6 }
             };
             using var selectedPen = new Pen(Color.Cyan, 2.5f)
             {
-                DashStyle = DashStyle.Dash
+                DashPattern = new float[] { 8, 6 }
             };
 
             for (var i = 0; i < Bends.Count; i++)

OpenNest/Controls/FileListControl.cs

@@ -62,12 +62,20 @@ namespace OpenNest.Controls
 
         public void AddItem(FileListItem item)
         {
-            items.Add(item);
+            var index = items.BinarySearch(item, Comparer<FileListItem>.Create(
+                (a, b) => string.Compare(a.Name, b.Name, StringComparison.OrdinalIgnoreCase)));
+            if (index < 0) index = ~index;
+            items.Insert(index, item);
+
             if (items.Count == 1)
             {
                 selectedIndex = 0;
                 SelectedIndexChanged?.Invoke(this, selectedIndex);
             }
+            else if (selectedIndex >= 0 && index <= selectedIndex)
+            {
+                selectedIndex++;
+            }
             Invalidate();
         }
 

OpenNest/Forms/CadConverterForm.Designer.cs

@@ -15,10 +15,9 @@ namespace OpenNest.Forms
 
         private void InitializeComponent()
         {
-            sidebarPanel = new System.Windows.Forms.Panel();
+            sidebarSplit = new System.Windows.Forms.SplitContainer();
             fileList = new OpenNest.Controls.FileListControl();
             filterPanel = new OpenNest.Controls.FilterPanel();
-            splitterSidebar = new System.Windows.Forms.Splitter();
             entityView1 = new OpenNest.Controls.EntityView();
             detailBar = new System.Windows.Forms.FlowLayoutPanel();
             lblQty = new System.Windows.Forms.Label();
@@ -33,204 +32,248 @@ namespace OpenNest.Forms
             bottomPanel1 = new OpenNest.Controls.BottomPanel();
             cancelButton = new System.Windows.Forms.Button();
             acceptButton = new System.Windows.Forms.Button();
-
+            ((System.ComponentModel.ISupportInitialize)sidebarSplit).BeginInit();
+            sidebarSplit.Panel1.SuspendLayout();
+            sidebarSplit.Panel2.SuspendLayout();
+            sidebarSplit.SuspendLayout();
+            detailBar.SuspendLayout();
             ((System.ComponentModel.ISupportInitialize)numQuantity).BeginInit();
-            sidebarPanel.SuspendLayout();
             bottomPanel1.SuspendLayout();
             SuspendLayout();
-
             // 
-            // sidebarPanel (Left dock — contains file list + filter panel)
+            // sidebarSplit
             // 
-            sidebarPanel.Dock = System.Windows.Forms.DockStyle.Left;
+            sidebarSplit.Dock = System.Windows.Forms.DockStyle.Left;
-            sidebarPanel.Name = "sidebarPanel";
+            sidebarSplit.Location = new System.Drawing.Point(0, 0);
-            sidebarPanel.Size = new System.Drawing.Size(260, 670);
+            sidebarSplit.Name = "sidebarSplit";
-            sidebarPanel.Controls.Add(filterPanel);
+            sidebarSplit.Orientation = System.Windows.Forms.Orientation.Horizontal;
-            sidebarPanel.Controls.Add(fileList);
-
             // 
-            // fileList (Top of sidebar)
+            // sidebarSplit.Panel1
+            // 
+            sidebarSplit.Panel1.Controls.Add(fileList);
+            // 
+            // sidebarSplit.Panel2
+            // 
+            sidebarSplit.Panel2.Controls.Add(filterPanel);
+            sidebarSplit.Size = new System.Drawing.Size(260, 670);
+            sidebarSplit.SplitterDistance = 300;
+            sidebarSplit.SplitterWidth = 5;
+            sidebarSplit.TabIndex = 2;
+            // 
+            // fileList
             // 
-            fileList.Dock = System.Windows.Forms.DockStyle.Top;
             fileList.AllowDrop = true;
+            fileList.BackColor = System.Drawing.Color.White;
+            fileList.Dock = System.Windows.Forms.DockStyle.Fill;
+            fileList.Font = new System.Drawing.Font("Segoe UI", 9F);
+            fileList.Location = new System.Drawing.Point(0, 0);
             fileList.Name = "fileList";
             fileList.Size = new System.Drawing.Size(260, 300);
-
+            fileList.TabIndex = 0;
             // 
-            // filterPanel (Fill remainder of sidebar)
+            // filterPanel
             // 
+            filterPanel.AutoScroll = true;
+            filterPanel.BackColor = System.Drawing.Color.White;
             filterPanel.Dock = System.Windows.Forms.DockStyle.Fill;
+            filterPanel.Location = new System.Drawing.Point(0, 0);
             filterPanel.Name = "filterPanel";
-            filterPanel.Size = new System.Drawing.Size(260, 370);
+            filterPanel.Size = new System.Drawing.Size(260, 365);
-
+            filterPanel.TabIndex = 0;
             // 
-            // splitterSidebar (between sidebar and preview)
+            // entityView1
-            //
-            splitterSidebar.Location = new System.Drawing.Point(260, 0);
-            splitterSidebar.Name = "splitterSidebar";
-            splitterSidebar.Size = new System.Drawing.Size(3, 670);
-            splitterSidebar.TabStop = false;
-
-            //
-            // entityView1 (Fill — main preview area)
             // 
             entityView1.BackColor = System.Drawing.Color.FromArgb(33, 40, 48);
             entityView1.Cursor = System.Windows.Forms.Cursors.Cross;
             entityView1.Dock = System.Windows.Forms.DockStyle.Fill;
+            entityView1.Location = new System.Drawing.Point(260, 0);
             entityView1.Name = "entityView1";
-            entityView1.Size = new System.Drawing.Size(761, 634);
+            entityView1.Size = new System.Drawing.Size(764, 634);
-
+            entityView1.TabIndex = 0;
             // 
-            // detailBar (Bottom of preview area)
+            // detailBar
             // 
-            detailBar.Dock = System.Windows.Forms.DockStyle.Bottom;
-            detailBar.Name = "detailBar";
-            detailBar.Size = new System.Drawing.Size(761, 36);
             detailBar.BackColor = System.Drawing.Color.FromArgb(245, 245, 245);
+            detailBar.Controls.Add(lblQty);
+            detailBar.Controls.Add(numQuantity);
+            detailBar.Controls.Add(lblCust);
+            detailBar.Controls.Add(txtCustomer);
+            detailBar.Controls.Add(lblDimensions);
+            detailBar.Controls.Add(lblEntityCount);
+            detailBar.Controls.Add(btnSplit);
+            detailBar.Controls.Add(lblDetect);
+            detailBar.Controls.Add(cboBendDetector);
+            detailBar.Dock = System.Windows.Forms.DockStyle.Bottom;
+            detailBar.Location = new System.Drawing.Point(260, 634);
+            detailBar.Name = "detailBar";
             detailBar.Padding = new System.Windows.Forms.Padding(4, 6, 4, 4);
+            detailBar.Size = new System.Drawing.Size(764, 36);
+            detailBar.TabIndex = 1;
             detailBar.WrapContents = false;
-
             // 
             // lblQty
             // 
-            lblQty.Text = "Qty:";
             lblQty.AutoSize = true;
-            lblQty.Font = new System.Drawing.Font("Segoe UI", 9f);
+            lblQty.Font = new System.Drawing.Font("Segoe UI", 9F);
+            lblQty.Location = new System.Drawing.Point(6, 9);
             lblQty.Margin = new System.Windows.Forms.Padding(2, 3, 0, 0);
-
+            lblQty.Name = "lblQty";
+            lblQty.Size = new System.Drawing.Size(29, 15);
+            lblQty.TabIndex = 0;
+            lblQty.Text = "Qty:";
             // 
             // numQuantity
             // 
-            numQuantity.Size = new System.Drawing.Size(50, 24);
+            numQuantity.Font = new System.Drawing.Font("Segoe UI", 9F);
-            numQuantity.Minimum = 1;
+            numQuantity.Location = new System.Drawing.Point(37, 6);
-            numQuantity.Maximum = 9999;
-            numQuantity.Value = 1;
-            numQuantity.Font = new System.Drawing.Font("Segoe UI", 9f);
             numQuantity.Margin = new System.Windows.Forms.Padding(2, 0, 8, 0);
-
+            numQuantity.Maximum = new decimal(new int[] { 9999, 0, 0, 0 });
+            numQuantity.Minimum = new decimal(new int[] { 1, 0, 0, 0 });
+            numQuantity.Name = "numQuantity";
+            numQuantity.Size = new System.Drawing.Size(50, 23);
+            numQuantity.TabIndex = 1;
+            numQuantity.Value = new decimal(new int[] { 1, 0, 0, 0 });
             // 
             // lblCust
             // 
-            lblCust.Text = "Customer:";
             lblCust.AutoSize = true;
-            lblCust.Font = new System.Drawing.Font("Segoe UI", 9f);
+            lblCust.Font = new System.Drawing.Font("Segoe UI", 9F);
+            lblCust.Location = new System.Drawing.Point(97, 9);
             lblCust.Margin = new System.Windows.Forms.Padding(2, 3, 0, 0);
-
+            lblCust.Name = "lblCust";
+            lblCust.Size = new System.Drawing.Size(62, 15);
+            lblCust.TabIndex = 2;
+            lblCust.Text = "Customer:";
             // 
             // txtCustomer
             // 
-            txtCustomer.Size = new System.Drawing.Size(100, 24);
-            txtCustomer.Font = new System.Drawing.Font("Segoe UI", 9f);
             txtCustomer.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
+            txtCustomer.Font = new System.Drawing.Font("Segoe UI", 9F);
+            txtCustomer.Location = new System.Drawing.Point(161, 6);
             txtCustomer.Margin = new System.Windows.Forms.Padding(2, 0, 8, 0);
-
+            txtCustomer.Name = "txtCustomer";
+            txtCustomer.Size = new System.Drawing.Size(100, 23);
+            txtCustomer.TabIndex = 3;
             // 
             // lblDimensions
             // 
             lblDimensions.AutoSize = true;
-            lblDimensions.Font = new System.Drawing.Font("Segoe UI", 9f);
+            lblDimensions.Font = new System.Drawing.Font("Segoe UI", 9F);
             lblDimensions.ForeColor = System.Drawing.Color.Gray;
+            lblDimensions.Location = new System.Drawing.Point(271, 9);
             lblDimensions.Margin = new System.Windows.Forms.Padding(2, 3, 8, 0);
-
+            lblDimensions.Name = "lblDimensions";
+            lblDimensions.Size = new System.Drawing.Size(0, 15);
+            lblDimensions.TabIndex = 4;
             // 
             // lblEntityCount
             // 
             lblEntityCount.AutoSize = true;
-            lblEntityCount.Font = new System.Drawing.Font("Segoe UI", 9f);
+            lblEntityCount.Font = new System.Drawing.Font("Segoe UI", 9F);
             lblEntityCount.ForeColor = System.Drawing.Color.Gray;
+            lblEntityCount.Location = new System.Drawing.Point(281, 9);
             lblEntityCount.Margin = new System.Windows.Forms.Padding(2, 3, 8, 0);
-
+            lblEntityCount.Name = "lblEntityCount";
+            lblEntityCount.Size = new System.Drawing.Size(0, 15);
+            lblEntityCount.TabIndex = 5;
             // 
             // btnSplit
             // 
-            btnSplit.Text = "Split...";
-            btnSplit.Size = new System.Drawing.Size(60, 24);
             btnSplit.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
-            btnSplit.Font = new System.Drawing.Font("Segoe UI", 9f);
+            btnSplit.Font = new System.Drawing.Font("Segoe UI", 9F);
+            btnSplit.Location = new System.Drawing.Point(291, 6);
             btnSplit.Margin = new System.Windows.Forms.Padding(2, 0, 8, 0);
-
+            btnSplit.Name = "btnSplit";
+            btnSplit.Size = new System.Drawing.Size(60, 24);
+            btnSplit.TabIndex = 6;
+            btnSplit.Text = "Split...";
             // 
             // lblDetect
             // 
-            lblDetect.Text = "Bends:";
             lblDetect.AutoSize = true;
-            lblDetect.Font = new System.Drawing.Font("Segoe UI", 9f);
+            lblDetect.Font = new System.Drawing.Font("Segoe UI", 9F);
+            lblDetect.Location = new System.Drawing.Point(361, 9);
             lblDetect.Margin = new System.Windows.Forms.Padding(2, 3, 0, 0);
-
+            lblDetect.Name = "lblDetect";
+            lblDetect.Size = new System.Drawing.Size(42, 15);
+            lblDetect.TabIndex = 7;
+            lblDetect.Text = "Bends:";
             // 
             // cboBendDetector
             // 
-            cboBendDetector.Size = new System.Drawing.Size(90, 24);
             cboBendDetector.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
-            cboBendDetector.Font = new System.Drawing.Font("Segoe UI", 9f);
+            cboBendDetector.Font = new System.Drawing.Font("Segoe UI", 9F);
+            cboBendDetector.Location = new System.Drawing.Point(405, 6);
             cboBendDetector.Margin = new System.Windows.Forms.Padding(2, 0, 0, 0);
-
+            cboBendDetector.Name = "cboBendDetector";
-            detailBar.Controls.AddRange(new System.Windows.Forms.Control[] {
+            cboBendDetector.Size = new System.Drawing.Size(90, 23);
-                lblQty, numQuantity, lblCust, txtCustomer,
+            cboBendDetector.TabIndex = 8;
-                lblDimensions, lblEntityCount, btnSplit,
-                lblDetect, cboBendDetector
-            });
-
             // 
             // bottomPanel1
             // 
-            bottomPanel1.Dock = System.Windows.Forms.DockStyle.Bottom;
-            bottomPanel1.Name = "bottomPanel1";
-            bottomPanel1.Size = new System.Drawing.Size(1024, 50);
             bottomPanel1.Controls.Add(cancelButton);
             bottomPanel1.Controls.Add(acceptButton);
-
+            bottomPanel1.Dock = System.Windows.Forms.DockStyle.Bottom;
+            bottomPanel1.Location = new System.Drawing.Point(0, 670);
+            bottomPanel1.Name = "bottomPanel1";
+            bottomPanel1.Size = new System.Drawing.Size(1024, 50);
+            bottomPanel1.TabIndex = 3;
             // 
             // cancelButton
             // 
             cancelButton.Anchor = System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right;
             cancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
-            cancelButton.Location = new System.Drawing.Point(922, 10);
-            cancelButton.Size = new System.Drawing.Size(90, 28);
-            cancelButton.Text = "Cancel";
             cancelButton.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
-            cancelButton.Font = new System.Drawing.Font("Segoe UI", 9f);
+            cancelButton.Font = new System.Drawing.Font("Segoe UI", 9F);
-
+            cancelButton.Location = new System.Drawing.Point(922, 10);
+            cancelButton.Name = "cancelButton";
+            cancelButton.Size = new System.Drawing.Size(90, 28);
+            cancelButton.TabIndex = 0;
+            cancelButton.Text = "Cancel";
             // 
             // acceptButton
             // 
             acceptButton.Anchor = System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right;
             acceptButton.DialogResult = System.Windows.Forms.DialogResult.OK;
-            acceptButton.Location = new System.Drawing.Point(826, 10);
-            acceptButton.Size = new System.Drawing.Size(90, 28);
-            acceptButton.Text = "Accept";
             acceptButton.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
-            acceptButton.Font = new System.Drawing.Font("Segoe UI", 9f);
+            acceptButton.Font = new System.Drawing.Font("Segoe UI", 9F);
-
+            acceptButton.Location = new System.Drawing.Point(826, 10);
+            acceptButton.Name = "acceptButton";
+            acceptButton.Size = new System.Drawing.Size(90, 28);
+            acceptButton.TabIndex = 1;
+            acceptButton.Text = "Accept";
             // 
             // CadConverterForm
-            // Add order: Fill last so it gets remaining space
             // 
+            AllowDrop = true;
             AutoScaleMode = System.Windows.Forms.AutoScaleMode.None;
             ClientSize = new System.Drawing.Size(1024, 720);
             Controls.Add(entityView1);
             Controls.Add(detailBar);
-            Controls.Add(splitterSidebar);
+            Controls.Add(sidebarSplit);
-            Controls.Add(sidebarPanel);
             Controls.Add(bottomPanel1);
-            Font = new System.Drawing.Font("Segoe UI", 9f);
+            Font = new System.Drawing.Font("Segoe UI", 9F);
             MinimizeBox = false;
+            Name = "CadConverterForm";
             ShowIcon = false;
             ShowInTaskbar = false;
             StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
             Text = "CAD Converter";
-            AllowDrop = true;
+            WindowState = System.Windows.Forms.FormWindowState.Maximized;
-
+            sidebarSplit.Panel1.ResumeLayout(false);
+            sidebarSplit.Panel2.ResumeLayout(false);
+            ((System.ComponentModel.ISupportInitialize)sidebarSplit).EndInit();
+            sidebarSplit.ResumeLayout(false);
+            detailBar.ResumeLayout(false);
+            detailBar.PerformLayout();
             ((System.ComponentModel.ISupportInitialize)numQuantity).EndInit();
-            sidebarPanel.ResumeLayout(false);
             bottomPanel1.ResumeLayout(false);
             ResumeLayout(false);
         }
 
         #endregion
 
-        private System.Windows.Forms.Panel sidebarPanel;
+        private System.Windows.Forms.SplitContainer sidebarSplit;
-        private System.Windows.Forms.Splitter splitterSidebar;
         private Controls.FileListControl fileList;
         private Controls.FilterPanel filterPanel;
         private Controls.EntityView entityView1;