feat(clone): choose Shift+click push order and add box-only Ctrl+click

Shift+click in Clone Parts always kept whichever axis order landed the
copy nearest the origin, which can park it in a pocket the user didn't
want. Options > Clone push placement now picks Closest to origin (the old
behavior, still the default), Push left then down, or Push down then left.

Ctrl+click settles the copy on bounding boxes alone, so it stops square
to its neighbors' boxes instead of nesting into their shapes. Shift+click
keeps its box pass then geometry settle; both follow the chosen order.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

OpenNest.Engine/Fill/Compactor.cs

@@ -390,29 +390,43 @@ namespace OpenNest.Engine.Fill
         }
 
         /// <summary>
-        /// Settles a copied placement against the plate in both axis orders, choosing
-        /// the group closest to the quadrant's work-area corner. A coarse box pass
-        /// runs only when no moving box starts inside an existing part's box.
+        /// Settles a copied placement against the plate. <see cref="SettleOrder.ClosestToCorner"/>
+        /// tries both axis orders and keeps the group closest to the quadrant's work-area
+        /// corner; the other orders push along the named axis first. A coarse box pass
+        /// runs only when no moving box starts inside an existing part's box. With
+        /// <paramref name="boundingBoxesOnly"/> every push uses bounding boxes alone, so the
+        /// group stops at the part spacing from obstacles' boxes, never nesting into their shapes.
         /// </summary>
         public static void SettlePlacement(
             List<Part> movingParts,
             Plate plate,
             PushDirection horizontal,
             PushDirection vertical,
-            int maxIterations = 20
+            int maxIterations = 20,
+            SettleOrder order = SettleOrder.ClosestToCorner,
+            bool boundingBoxesOnly = false
         )
         {
             if (movingParts.Count == 0)
                 return;
 
             var workArea = plate.WorkArea();
-            var skipBoxes = movingParts.Any(moving =>
+            var skipBoxes = boundingBoxesOnly || movingParts.Any(moving =>
                 plate.Parts.Any(obstacle => moving.BoundingBox.Intersects(obstacle.BoundingBox))
             );
+            double PushOnce(List<Part> trial, PushDirection direction) => boundingBoxesOnly
+                ? PushBoundingBox(trial, plate, direction)
+                : Push(trial, plate, direction);
             var bestScore = double.MaxValue;
             Vector[] best = null;
+            var firstAxes = order switch
+            {
+                SettleOrder.HorizontalFirst => new[] { horizontal },
+                SettleOrder.VerticalFirst => new[] { vertical },
+                _ => new[] { horizontal, vertical },
+            };
 
-            foreach (var first in new[] { horizontal, vertical })
+            foreach (var first in firstAxes)
             {
                 var second = first == horizontal ? vertical : horizontal;
                 var trial = movingParts.Select(p => (Part)p.Clone()).ToList();
@@ -424,7 +438,7 @@ namespace OpenNest.Engine.Fill
 
                 for (var i = 0; i < maxIterations; i++)
                 {
-                    var moved = Push(trial, plate, first) + Push(trial, plate, second);
+                    var moved = PushOnce(trial, first) + PushOnce(trial, second);
                     if (moved < 0.01)
                         break;
                 }

OpenNest.Engine/Fill/SettleOrder.cs

@@ -0,0 +1,18 @@
+namespace OpenNest.Engine.Fill
+{
+    /// <summary>
+    /// How <see cref="Compactor.SettlePlacement"/> orders its pushes. Directions follow
+    /// the plate's origin quadrant: "horizontal" is toward the origin's side, as is "vertical".
+    /// </summary>
+    public enum SettleOrder
+    {
+        /// <summary>Try both orders and keep the placement closest to the origin corner.</summary>
+        ClosestToCorner,
+
+        /// <summary>Push horizontally first, then vertically, repeating until settled.</summary>
+        HorizontalFirst,
+
+        /// <summary>Push vertically first, then horizontally, repeating until settled.</summary>
+        VerticalFirst,
+    }
+}

OpenNest.Tests/Fill/CompactorTests.cs

@@ -644,6 +644,58 @@ namespace OpenNest.Tests.Fill
             Assert.Equal(start, moving.Location);
         }
 
+        // Two pockets: pushing left first parks the part on the tall block at (20, 55);
+        // pushing down first parks it on the low floor at (55, 10), nearer the origin.
+        private static Plate TwoPocketPlate()
+        {
+            var plate = new Plate(100, 100);
+            plate.Parts.Add(MakeRectPart(0, 0, 20, 100));
+            plate.Parts.Add(MakeRectPart(20, 0, 35, 55));
+            plate.Parts.Add(MakeRectPart(55, 0, 45, 10));
+            return plate;
+        }
+
+        [Theory]
+        [InlineData(SettleOrder.ClosestToCorner, 55, 10)]
+        [InlineData(SettleOrder.HorizontalFirst, 20, 55)]
+        [InlineData(SettleOrder.VerticalFirst, 55, 10)]
+        public void SettlePlacement_OrderChoosesThePocket(SettleOrder order, double left, double bottom)
+        {
+            var plate = TwoPocketPlate();
+            var moving = MakeRectPart(60, 60, 10, 10);
+
+            Compactor.SettlePlacement(new List<Part> { moving }, plate,
+                PushDirection.Left, PushDirection.Down, order: order);
+
+            Assert.Equal(left, moving.BoundingBox.Left, 3);
+            Assert.Equal(bottom, moving.BoundingBox.Bottom, 3);
+            Assert.All(plate.Parts, obstacle => Assert.False(moving.Intersects(obstacle, out _)));
+        }
+
+        [Fact]
+        public void SettlePlacement_BoundingBoxesOnlyStopsAtTheObstacleBox()
+        {
+            // Triangle material is below the diagonal; geometry lets the square slide in
+            // over the hypotenuse, boxes stop it square to the triangle's bounds. The floor
+            // keeps both above y = 5.
+            var plate = new Plate(100, 100);
+            plate.Parts.Add(MakeTrianglePart(new Vector(0, 0),
+                new Vector(40, 0), new Vector(0, 40)));
+            plate.Parts.Add(MakeRectPart(40, 0, 60, 5));
+            var geometry = MakeRectPart(50, 6, 5, 5);
+            var boxes = MakeRectPart(50, 6, 5, 5);
+
+            Compactor.SettlePlacement(new List<Part> { geometry }, plate,
+                PushDirection.Left, PushDirection.Down, order: SettleOrder.HorizontalFirst);
+            Compactor.SettlePlacement(new List<Part> { boxes }, plate,
+                PushDirection.Left, PushDirection.Down, order: SettleOrder.HorizontalFirst,
+                boundingBoxesOnly: true);
+
+            Assert.True(geometry.BoundingBox.Left < 39, $"geometry left {geometry.BoundingBox.Left}");
+            Assert.InRange(boxes.BoundingBox.Left, 40, 40.01);
+            Assert.InRange(boxes.BoundingBox.Bottom, 5, 5.01);
+        }
+
         [Fact]
         public void PushBoundingBox_Left_MovesPartTowardEdge()
         {

OpenNest.WinForms.Tests/Controls/ActionCloneTests.cs

@@ -92,6 +92,28 @@ public class ActionCloneTests
         Assert.Single(plate.Parts);
     }, TimeSpan.FromMinutes(1), "The STA test did not complete.");
 
+    [Theory]
+    [InlineData(Keys.Shift)]
+    [InlineData(Keys.Control)]
+    public void ModifiedClickPushesTheCopyAgainstPlacedParts(Keys modifiers) => StaTestThread.Run(() =>
+    {
+        var plate = new Plate(48, 96) { PartSpacing = 0 };
+        plate.Parts.Add(new Part(Square("placed")));
+        using var view = new PlateView { Plate = plate, Size = new System.Drawing.Size(600, 600) };
+        view.ZoomToFit();
+        view.SetAction(typeof(ActionClone), Square("new"));
+        var action = Assert.IsType<ActionClone>(view.Actions.CurrentAction);
+        action.PlacementOrder = OpenNest.Engine.Fill.SettleOrder.VerticalFirst;
+        var preview = Assert.Single(view.SelectedParts);
+        preview.BasePart.Location = new Vector(20, 1);
+
+        action.Apply(modifiers);
+
+        var copy = plate.Parts[1].BoundingBox;
+        Assert.InRange(copy.Left, 4, 4.01);
+        Assert.Equal(0, copy.Bottom, 6);
+    }, TimeSpan.FromMinutes(1), "The STA test did not complete.");
+
     [Fact]
     public void ADialogsFakeMouseMoveLeavesNudgedPreviewsInPlace() => StaTestThread.Run(() =>
     {

OpenNest/Actions/ActionClone.cs

@@ -200,11 +200,30 @@ namespace OpenNest.Actions
             change.Complete();
         }
 
-        public void Apply()
+        /// <summary>
+        /// Which way Shift+click and Ctrl+click push the copy; null reads the user's Options
+        /// setting at each click, so a change there applies without restarting the action.
+        /// </summary>
+        public SettleOrder? PlacementOrder { get; set; }
+
+        // An unknown stored name falls back to the closest-to-origin search.
+        internal static SettleOrder ReadPlacementOrder() =>
+            System.Enum.TryParse<SettleOrder>(Properties.Settings.Default.ClonePlacementOrder, out var order)
+                && System.Enum.IsDefined(order)
+                ? order
+                : SettleOrder.ClosestToCorner;
+
+        public void Apply() => Apply(Control.ModifierKeys);
+
+        // Shift settles on the parts' geometry (a box pass first when clear); Ctrl settles on
+        // bounding boxes alone, so the copy stops square to its neighbors' boxes.
+        internal void Apply(Keys modifiers)
         {
             using var change = plateView.BeginChange(parts.Count == 1 ? "Add Part" : "Add Parts");
             change.MarkChanged();
-            if ((Control.ModifierKeys & Keys.Shift) == Keys.Shift)
+            var shift = (modifiers & Keys.Shift) == Keys.Shift;
+            var boxesOnly = !shift && (modifiers & Keys.Control) == Keys.Control;
+            if (shift || boxesOnly)
             {
                 var movingParts = parts.Select(p => p.BasePart).ToList();
 
@@ -234,7 +253,8 @@ namespace OpenNest.Actions
                         break;
                 }
 
-                Compactor.SettlePlacement(movingParts, plateView.Plate, hDir, vDir);
+                Compactor.SettlePlacement(movingParts, plateView.Plate, hDir, vDir,
+                    order: PlacementOrder ?? ReadPlacementOrder(), boundingBoxesOnly: boxesOnly);
 
                 parts.ForEach(p => p.IsDirty = true);
                 plateView.Invalidate();

OpenNest/Forms/OptionsForm.Designer.cs

@@ -43,6 +43,8 @@
             this.strategyGroupBox = new System.Windows.Forms.GroupBox();
             this.colorSchemeLabel = new System.Windows.Forms.Label();
             this.colorSchemeCombo = new System.Windows.Forms.ComboBox();
+            this.clonePlacementLabel = new System.Windows.Forms.Label();
+            this.clonePlacementCombo = new System.Windows.Forms.ComboBox();
             this.serverGroupBox = new System.Windows.Forms.GroupBox();
             this.serverUrlBox = new System.Windows.Forms.TextBox();
             this.setServerButton = new System.Windows.Forms.Button();
@@ -71,7 +73,7 @@
             this.checkBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Left | System.Windows.Forms.AnchorStyles.Right)));
             this.checkBox1.AutoSize = true;
             this.tableLayoutPanel1.SetColumnSpan(this.checkBox1, 2);
-            this.checkBox1.Location = new System.Drawing.Point(3, 165);
+            this.checkBox1.Location = new System.Drawing.Point(3, 213);
             this.checkBox1.Name = "checkBox1";
             this.checkBox1.Size = new System.Drawing.Size(281, 20);
             this.checkBox1.TabIndex = 7;
@@ -143,16 +145,19 @@
             this.tableLayoutPanel1.Controls.Add(this.colorSchemeCombo, 1, 1);
             this.tableLayoutPanel1.Controls.Add(this.planningEffortLabel, 0, 2);
             this.tableLayoutPanel1.Controls.Add(this.planningEffortBox, 1, 2);
-            this.tableLayoutPanel1.Controls.Add(this.checkBox1, 0, 3);
+            this.tableLayoutPanel1.Controls.Add(this.clonePlacementLabel, 0, 3);
+            this.tableLayoutPanel1.Controls.Add(this.clonePlacementCombo, 1, 3);
+            this.tableLayoutPanel1.Controls.Add(this.checkBox1, 0, 4);
             this.tableLayoutPanel1.Controls.Add(this.numericUpDown1, 1, 0);
             this.tableLayoutPanel1.Location = new System.Drawing.Point(12, 12);
             this.tableLayoutPanel1.Name = "tableLayoutPanel1";
-            this.tableLayoutPanel1.RowCount = 4;
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 25F));
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 25F));
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 25F));
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 25F));
-            this.tableLayoutPanel1.Size = new System.Drawing.Size(684, 200);
+            this.tableLayoutPanel1.RowCount = 5;
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 20F));
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 20F));
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 20F));
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 20F));
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 20F));
+            this.tableLayoutPanel1.Size = new System.Drawing.Size(684, 240);
             this.tableLayoutPanel1.TabIndex = 0;
             // 
             // saveButton
@@ -185,7 +190,7 @@
             this.bottomPanel1.Controls.Add(this.cancelButton);
             this.bottomPanel1.Controls.Add(this.saveButton);
             this.bottomPanel1.Dock = System.Windows.Forms.DockStyle.Bottom;
-            this.bottomPanel1.Location = new System.Drawing.Point(0, 647);
+            this.bottomPanel1.Location = new System.Drawing.Point(0, 715);
             this.bottomPanel1.Name = "bottomPanel1";
             this.bottomPanel1.Size = new System.Drawing.Size(708, 50);
             this.bottomPanel1.TabIndex = 1;
@@ -204,7 +209,7 @@
             // strategyGroupBox
             //
             this.strategyGroupBox.Controls.Add(this.strategyGrid);
-            this.strategyGroupBox.Location = new System.Drawing.Point(12, 485);
+            this.strategyGroupBox.Location = new System.Drawing.Point(12, 525);
             this.strategyGroupBox.Name = "strategyGroupBox";
             this.strategyGroupBox.Size = new System.Drawing.Size(684, 180);
             this.strategyGroupBox.TabIndex = 2;
@@ -230,11 +235,32 @@
             this.colorSchemeCombo.Size = new System.Drawing.Size(130, 24);
             this.colorSchemeCombo.TabIndex = 11;
             //
+            // clonePlacementLabel
+            //
+            this.clonePlacementLabel.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Left | System.Windows.Forms.AnchorStyles.Right)));
+            this.clonePlacementLabel.AutoSize = true;
+            this.clonePlacementLabel.Location = new System.Drawing.Point(3, 172);
+            this.clonePlacementLabel.Name = "clonePlacementLabel";
+            this.clonePlacementLabel.Size = new System.Drawing.Size(145, 16);
+            this.clonePlacementLabel.TabIndex = 14;
+            this.clonePlacementLabel.Text = "Clone push placement:";
+            //
+            // clonePlacementCombo
+            //
+            this.clonePlacementCombo.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Left | System.Windows.Forms.AnchorStyles.Right)));
+            this.clonePlacementCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+            this.clonePlacementCombo.Location = new System.Drawing.Point(154, 168);
+            this.clonePlacementCombo.Name = "clonePlacementCombo";
+            this.clonePlacementCombo.Size = new System.Drawing.Size(130, 24);
+            this.clonePlacementCombo.TabIndex = 15;
+            this.toolTip1.SetToolTip(this.clonePlacementCombo, "Where Clone Parts pushes the copy on Shift+click (part geometry) "
+                + "or Ctrl+click (bounding boxes). Left and down mirror for plates whose origin is in another corner.");
+            //
             // serverGroupBox
             //
             this.serverGroupBox.Controls.Add(this.serverUrlBox);
             this.serverGroupBox.Controls.Add(this.setServerButton);
-            this.serverGroupBox.Location = new System.Drawing.Point(12, 218);
+            this.serverGroupBox.Location = new System.Drawing.Point(12, 258);
             this.serverGroupBox.Name = "serverGroupBox";
             this.serverGroupBox.Size = new System.Drawing.Size(684, 69);
             this.serverGroupBox.TabIndex = 1;
@@ -264,7 +290,7 @@
             this.updateGroupBox.Controls.Add(this.updateFeedUrlBox);
             this.updateGroupBox.Controls.Add(this.setUpdateFeedButton);
             this.updateGroupBox.Controls.Add(this.includeDevBuildsBox);
-            this.updateGroupBox.Location = new System.Drawing.Point(12, 391);
+            this.updateGroupBox.Location = new System.Drawing.Point(12, 431);
             this.updateGroupBox.Name = "updateGroupBox";
             this.updateGroupBox.Size = new System.Drawing.Size(684, 88);
             this.updateGroupBox.TabIndex = 3;
@@ -307,7 +333,7 @@
             this.ledgerGroupBox.Controls.Add(this.ledgerKeyBox);
             this.ledgerGroupBox.Controls.Add(this.testLedgerButton);
             this.ledgerGroupBox.Controls.Add(this.saveLedgerButton);
-            this.ledgerGroupBox.Location = new System.Drawing.Point(12, 293);
+            this.ledgerGroupBox.Location = new System.Drawing.Point(12, 333);
             this.ledgerGroupBox.Name = "ledgerGroupBox";
             this.ledgerGroupBox.Size = new System.Drawing.Size(684, 92);
             this.ledgerGroupBox.TabIndex = 4;
@@ -374,7 +400,7 @@
             this.AcceptButton = this.saveButton;
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.None;
             this.CancelButton = this.cancelButton;
-            this.ClientSize = new System.Drawing.Size(708, 725);
+            this.ClientSize = new System.Drawing.Size(708, 765);
             this.Controls.Add(this.strategyGroupBox);
             this.Controls.Add(this.updateGroupBox);
             this.Controls.Add(this.ledgerGroupBox);
@@ -421,6 +447,8 @@
         private System.Windows.Forms.GroupBox strategyGroupBox;
         private System.Windows.Forms.Label colorSchemeLabel;
         private System.Windows.Forms.ComboBox colorSchemeCombo;
+        private System.Windows.Forms.Label clonePlacementLabel;
+        private System.Windows.Forms.ComboBox clonePlacementCombo;
         private System.Windows.Forms.GroupBox serverGroupBox;
         private System.Windows.Forms.TextBox serverUrlBox;
         private System.Windows.Forms.Button setServerButton;

OpenNest/Forms/OptionsForm.cs

@@ -3,10 +3,12 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
 using System.Windows.Forms;
+using OpenNest.Actions;
 using OpenNest.Controls;
 using OpenNest.Data;
 using OpenNest.Data.MaterialLedger;
 using OpenNest.Engine.CuttingPlanning;
+using OpenNest.Engine.Fill;
 using OpenNest.Engine.Strategies;
 using OpenNest.Properties;
 
@@ -14,6 +16,14 @@ namespace OpenNest.Forms
 {
     public partial class OptionsForm : Form
     {
+        // Combo order matches these; the setting stores the enum name.
+        private static readonly (SettleOrder Order, string Text)[] ClonePlacements =
+        {
+            (SettleOrder.ClosestToCorner, "Closest to origin"),
+            (SettleOrder.HorizontalFirst, "Push left, then down"),
+            (SettleOrder.VerticalFirst, "Push down, then left"),
+        };
+
         public OptionsForm()
         {
             InitializeComponent();
@@ -96,6 +106,13 @@ namespace OpenNest.Forms
             var idx = colorSchemeCombo.Items.IndexOf(active);
             colorSchemeCombo.SelectedIndex = idx >= 0 ? idx : 0;
 
+            clonePlacementCombo.Items.Clear();
+            foreach (var (_, text) in ClonePlacements)
+                clonePlacementCombo.Items.Add(text);
+            var placement = ActionClone.ReadPlacementOrder();
+            clonePlacementCombo.SelectedIndex = System.Math.Max(0,
+                System.Array.FindIndex(ClonePlacements, p => p.Order == placement));
+
             var disabledNames = ParseDisabledStrategies(Settings.Default.DisabledStrategies);
             foreach (DataGridViewRow row in strategyGrid.Rows)
                 row.Cells["Enabled"].Value = !disabledNames.Contains(
@@ -111,6 +128,8 @@ namespace OpenNest.Forms
             Settings.Default.CuttingPlanEffort = (double)planningEffortBox.Value;
             Settings.Default.ActiveColorScheme =
                 colorSchemeCombo.SelectedItem as string ?? "Classic";
+            Settings.Default.ClonePlacementOrder =
+                ClonePlacements[System.Math.Max(0, clonePlacementCombo.SelectedIndex)].Order.ToString();
 
             var disabledNames = new List<string>();
             foreach (DataGridViewRow row in strategyGrid.Rows)

OpenNest/Properties/Settings.Designer.cs

@@ -488,5 +488,18 @@ namespace OpenNest.Properties {
                 this["MadeBy"] = value;
             }
         }
+
+        [global::System.Configuration.UserScopedSettingAttribute()]
+        [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+        [global::System.Configuration.DefaultSettingValueAttribute("ClosestToCorner")]
+        // Where Shift+click in Clone Parts pushes the copy: an OpenNest.Engine.Fill.SettleOrder name.
+        public string ClonePlacementOrder {
+            get {
+                return ((string)(this["ClonePlacementOrder"]));
+            }
+            set {
+                this["ClonePlacementOrder"] = value;
+            }
+        }
     }
 }

OpenNest/Properties/Settings.settings

@@ -116,5 +116,8 @@
     <Setting Name="MadeBy" Type="System.String" Scope="User">
       <Value Profile="(Default)" />
     </Setting>
+    <Setting Name="ClonePlacementOrder" Type="System.String" Scope="User">
+      <Value Profile="(Default)">ClosestToCorner</Value>
+    </Setting>
   </Settings>
 </SettingsFile>

docs/geometry/directional-slides.md

@@ -16,7 +16,9 @@ Open/incomplete chains and ambiguous contacts conservatively block. Loops are re
 - CPU best-fit batches prepare contact topology once and use all vertices plus curve/line interior and curve/curve tangency events. The old leading-half vertex filter cannot establish the next blocker after a skipped touch.
 - GPU kernels retain nearest-hit reduction and return unsnapped contact witnesses. The shared CPU classifier accepts a blocking witness or replays the full query after a nonblocking witness, preserving tied/later blockers. Both batch APIs honor active buffer lengths and refresh mutated/reused segment arrays. The GPU distance adapter sends only exact cardinal directions to the axis-only slide interface; arbitrary directions and native curves use the shared CPU path.
 
-- Shift-click while cloning parts settles the copied group toward the plate quadrant. If its starting bounds overlap any placed part's bounds, it skips the coarse bounding-box pass and uses geometry directly; otherwise it tries coarse horizontal/vertical and vertical/horizontal orders. Each candidate then alternates geometry pushes until movement is negligible (at most 20 iterations), and the group nearest the quadrant's work-area corner wins. The coarse pass remains useful for avoiding sawtooth/rung traps when the starting boxes do not overlap.
+- Shift-click while cloning parts settles the copied group toward the plate quadrant. If its starting bounds overlap any placed part's bounds, it skips the coarse bounding-box pass and uses geometry directly; otherwise each axis order starts with a coarse box pass. Each candidate then alternates geometry pushes until movement is negligible (at most 20 iterations). The coarse pass remains useful for avoiding sawtooth/rung traps when the starting boxes do not overlap.
+- Ctrl-click settles the same way on bounding boxes alone (`SettlePlacement(boundingBoxesOnly: true)`): every push stops at the part spacing from obstacles' boxes, so the copy never nests into a neighbor's shape. A group whose box already overlaps an obstacle's box does not move.
+- Options > Clone push placement (`ClonePlacementOrder`, a `SettleOrder` name) picks the axis order for both: *Closest to origin* (default) tries horizontal-first and vertical-first and keeps the group nearest the quadrant's work-area corner; *Push left, then down* and *Push down, then left* run only that order. Left and down mirror with the plate quadrant.
 
 ## Regression coverage
 `SlideContactTests` exercises cardinal line, translated line, reused edge-array, arbitrary-vector, native-entity, and both CPU batch paths. Cases include winding reversal, nonzero origins, rotated hooks, holes, separating circles, positive-distance grazing followed by a blocker, full-circle arc seams, concave/straight junctions, thin rings, and circle/line interior contact.