feat: improve multi-plate nesting with multi-remnant filling and better zone scoring

- Iterate all remnants instead of only the first when packing and filling
- Improve ScoreZone with estimated part count and aspect ratio matching
- Cache bounding boxes in SortItems and remnants in TryPlaceOnExistingPlates
- Make TryConsolidateTailPlates loop until stable, trying all donor/target pairs
- Fix consolidation grouping to use BaseDrawing reference instead of name

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

OpenNest.Core/Geometry/SpatialQuery.cs

@@ -596,6 +596,138 @@ namespace OpenNest.Geometry
             return minDist;
         }
 
+        /// <summary>
+        /// Computes the minimum translation distance along an arbitrary unit direction
+        /// before any vertex/edge of movingEntities contacts any vertex/edge of
+        /// stationaryEntities. Works with native Line, Arc, and Circle entities
+        /// without tessellation.
+        /// </summary>
+        public static double DirectionalDistance(
+            List<Entity> movingEntities, List<Entity> stationaryEntities, Vector direction)
+        {
+            var minDist = double.MaxValue;
+            var dirX = direction.X;
+            var dirY = direction.Y;
+
+            var movingVertices = ExtractEntityVertices(movingEntities);
+
+            for (var v = 0; v < movingVertices.Length; v++)
+            {
+                var vx = movingVertices[v].X;
+                var vy = movingVertices[v].Y;
+
+                for (var j = 0; j < stationaryEntities.Count; j++)
+                {
+                    var d = RayEntityDistance(vx, vy, stationaryEntities[j], dirX, dirY);
+                    if (d < minDist)
+                    {
+                        minDist = d;
+                        if (d <= 0) return 0;
+                    }
+                }
+            }
+
+            var oppX = -dirX;
+            var oppY = -dirY;
+
+            var stationaryVertices = ExtractEntityVertices(stationaryEntities);
+
+            for (var v = 0; v < stationaryVertices.Length; v++)
+            {
+                var vx = stationaryVertices[v].X;
+                var vy = stationaryVertices[v].Y;
+
+                for (var j = 0; j < movingEntities.Count; j++)
+                {
+                    var d = RayEntityDistance(vx, vy, movingEntities[j], oppX, oppY);
+                    if (d < minDist)
+                    {
+                        minDist = d;
+                        if (d <= 0) return 0;
+                    }
+                }
+            }
+
+            return minDist;
+        }
+
+        private static double RayEntityDistance(
+            double vx, double vy, Entity entity, double dirX, double dirY)
+        {
+            if (entity is Line line)
+            {
+                return RayEdgeDistance(vx, vy,
+                    line.pt1.X, line.pt1.Y, line.pt2.X, line.pt2.Y,
+                    dirX, dirY);
+            }
+
+            if (entity is Arc arc)
+            {
+                return RayArcDistance(vx, vy,
+                    arc.Center.X, arc.Center.Y, arc.Radius,
+                    arc.StartAngle, arc.EndAngle, arc.IsReversed,
+                    dirX, dirY);
+            }
+
+            if (entity is Circle circle)
+            {
+                return RayCircleDistance(vx, vy,
+                    circle.Center.X, circle.Center.Y, circle.Radius,
+                    dirX, dirY);
+            }
+
+            return double.MaxValue;
+        }
+
+        private static Vector[] ExtractEntityVertices(List<Entity> entities)
+        {
+            var vertices = new HashSet<Vector>();
+
+            for (var i = 0; i < entities.Count; i++)
+            {
+                var entity = entities[i];
+
+                if (entity is Line line)
+                {
+                    vertices.Add(line.pt1);
+                    vertices.Add(line.pt2);
+                }
+                else if (entity is Arc arc)
+                {
+                    vertices.Add(arc.StartPoint());
+                    vertices.Add(arc.EndPoint());
+                    AddArcExtremeVertices(vertices, arc);
+                }
+                else if (entity is Circle circle)
+                {
+                    vertices.Add(new Vector(circle.Center.X + circle.Radius, circle.Center.Y));
+                    vertices.Add(new Vector(circle.Center.X - circle.Radius, circle.Center.Y));
+                    vertices.Add(new Vector(circle.Center.X, circle.Center.Y + circle.Radius));
+                    vertices.Add(new Vector(circle.Center.X, circle.Center.Y - circle.Radius));
+                }
+            }
+
+            return vertices.ToArray();
+        }
+
+        private static void AddArcExtremeVertices(HashSet<Vector> points, Arc arc)
+        {
+            var a1 = arc.StartAngle;
+            var a2 = arc.EndAngle;
+
+            if (arc.IsReversed)
+                Generic.Swap(ref a1, ref a2);
+
+            if (Angle.IsBetweenRad(Angle.TwoPI, a1, a2))
+                points.Add(new Vector(arc.Center.X + arc.Radius, arc.Center.Y));
+            if (Angle.IsBetweenRad(Angle.HalfPI, a1, a2))
+                points.Add(new Vector(arc.Center.X, arc.Center.Y + arc.Radius));
+            if (Angle.IsBetweenRad(System.Math.PI, a1, a2))
+                points.Add(new Vector(arc.Center.X - arc.Radius, arc.Center.Y));
+            if (Angle.IsBetweenRad(System.Math.PI * 1.5, a1, a2))
+                points.Add(new Vector(arc.Center.X, arc.Center.Y - arc.Radius));
+        }
+
         private static double BoxProjectionMin(Box box, double dx, double dy)
         {
             var x = dx >= 0 ? box.Left : box.Right;

OpenNest.Core/PartGeometry.cs

@@ -61,6 +61,91 @@ namespace OpenNest
             return offsetShape.Entities;
         }
 
+        /// <summary>
+        /// Returns all entities (perimeter + cutouts) with spacing offset applied,
+        /// without tessellation. Perimeter is offset outward, cutouts inward.
+        /// </summary>
+        public static List<Entity> GetOffsetPartEntities(Part part, double spacing)
+        {
+            var geoEntities = ConvertProgram.ToGeometry(part.Program);
+            var profile = new ShapeProfile(
+                geoEntities.Where(e => e.Layer != SpecialLayers.Rapid).ToList());
+            var entities = new List<Entity>();
+
+            var perimeter = profile.Perimeter.OffsetOutward(spacing);
+            if (perimeter != null)
+            {
+                foreach (var entity in perimeter.Entities)
+                    entity.Offset(part.Location);
+                entities.AddRange(perimeter.Entities);
+            }
+
+            foreach (var cutout in profile.Cutouts)
+            {
+                var inset = cutout.OffsetInward(spacing);
+                if (inset == null) continue;
+                foreach (var entity in inset.Entities)
+                    entity.Offset(part.Location);
+                entities.AddRange(inset.Entities);
+            }
+
+            return entities;
+        }
+
+        /// <summary>
+        /// Returns perimeter entities at the part's world location, without tessellation
+        /// or spacing offset.
+        /// </summary>
+        public static List<Entity> GetPerimeterEntities(Part part)
+        {
+            var geoEntities = ConvertProgram.ToGeometry(part.Program);
+            var profile = new ShapeProfile(
+                geoEntities.Where(e => e.Layer != SpecialLayers.Rapid).ToList());
+
+            return CopyEntitiesAtLocation(profile.Perimeter.Entities, part.Location);
+        }
+
+        /// <summary>
+        /// Returns all entities (perimeter + cutouts) at the part's world location,
+        /// without tessellation or spacing offset.
+        /// </summary>
+        public static List<Entity> GetPartEntities(Part part)
+        {
+            var geoEntities = ConvertProgram.ToGeometry(part.Program);
+            var profile = new ShapeProfile(
+                geoEntities.Where(e => e.Layer != SpecialLayers.Rapid).ToList());
+            var entities = CopyEntitiesAtLocation(profile.Perimeter.Entities, part.Location);
+
+            foreach (var cutout in profile.Cutouts)
+                entities.AddRange(CopyEntitiesAtLocation(cutout.Entities, part.Location));
+
+            return entities;
+        }
+
+        private static List<Entity> CopyEntitiesAtLocation(List<Entity> source, Vector location)
+        {
+            var result = new List<Entity>(source.Count);
+
+            for (var i = 0; i < source.Count; i++)
+            {
+                var entity = source[i];
+                Entity copy;
+
+                if (entity is Line line)
+                    copy = new Line(line.StartPoint + location, line.EndPoint + location);
+                else if (entity is Arc arc)
+                    copy = new Arc(arc.Center + location, arc.Radius, arc.StartAngle, arc.EndAngle, arc.IsReversed);
+                else if (entity is Circle circle)
+                    copy = new Circle(circle.Center + location, circle.Radius);
+                else
+                    continue;
+
+                result.Add(copy);
+            }
+
+            return result;
+        }
+
         public static List<Line> GetOffsetPartLines(Part part, double spacing, double chordTolerance = 0.001,
             bool perimeterOnly = false)
         {

OpenNest.Engine/BestFit/BestFitFilter.cs

@@ -17,7 +17,8 @@ namespace OpenNest.Engine.BestFit
                 if (!result.Keep)
                     continue;
 
-                if (result.ShortestSide > System.Math.Min(MaxPlateWidth, MaxPlateHeight))
+                if (result.ShortestSide > System.Math.Min(MaxPlateWidth, MaxPlateHeight) ||
+                    result.LongestSide > System.Math.Max(MaxPlateWidth, MaxPlateHeight))
                 {
                     result.Keep = false;
                     result.Reason = "Exceeds plate dimensions";

OpenNest.Engine/Fill/Compactor.cs

@@ -11,8 +11,6 @@ namespace OpenNest.Engine.Fill
     /// </summary>
     public static class Compactor
     {
-        private const double ChordTolerance = 0.001;
-
         public static double Push(List<Part> movingParts, Plate plate, PushDirection direction)
         {
             var obstacleParts = plate.Parts
@@ -44,7 +42,7 @@ namespace OpenNest.Engine.Fill
             var opposite = -direction;
 
             var obstacleBoxes = new Box[obstacleParts.Count];
-            var obstacleLines = new List<Line>[obstacleParts.Count];
+            var obstacleEntities = new List<Entity>[obstacleParts.Count];
 
             for (var i = 0; i < obstacleParts.Count; i++)
                 obstacleBoxes[i] = obstacleParts[i].BoundingBox;
@@ -61,7 +59,19 @@ namespace OpenNest.Engine.Fill
                     distance = edgeDist;
 
                 var movingBox = moving.BoundingBox;
-                List<Line> movingLines = null;
+                List<Entity> movingEntities = null;
+
+                // Check if any obstacle is inside the moving part — only then
+                // do we need cutout entities on the moving part.
+                var needCutouts = false;
+                for (var i = 0; i < obstacleBoxes.Length; i++)
+                {
+                    if (movingBox.Contains(obstacleBoxes[i]))
+                    {
+                        needCutouts = true;
+                        break;
+                    }
+                }
 
                 for (var i = 0; i < obstacleBoxes.Length; i++)
                 {
@@ -76,15 +86,19 @@ namespace OpenNest.Engine.Fill
                     if (!SpatialQuery.PerpendicularOverlap(movingBox, obstacleBoxes[i], direction))
                         continue;
 
-                    movingLines ??= halfSpacing > 0
+                    movingEntities ??= halfSpacing > 0
-                        ? PartGeometry.GetOffsetPartLines(moving, halfSpacing, direction, ChordTolerance)
+                        ? (needCutouts
-                        : PartGeometry.GetPartLines(moving, direction, ChordTolerance);
+                            ? PartGeometry.GetOffsetPartEntities(moving, halfSpacing)
+                            : PartGeometry.GetOffsetPerimeterEntities(moving, halfSpacing))
+                        : (needCutouts
+                            ? PartGeometry.GetPartEntities(moving)
+                            : PartGeometry.GetPerimeterEntities(moving));
 
-                    obstacleLines[i] ??= halfSpacing > 0
+                    obstacleEntities[i] ??= halfSpacing > 0
-                        ? PartGeometry.GetOffsetPartLines(obstacleParts[i], halfSpacing, opposite, ChordTolerance)
+                        ? PartGeometry.GetOffsetPerimeterEntities(obstacleParts[i], halfSpacing)
-                        : PartGeometry.GetPartLines(obstacleParts[i], opposite, ChordTolerance);
+                        : PartGeometry.GetPerimeterEntities(obstacleParts[i]);
 
-                    var d = SpatialQuery.DirectionalDistance(movingLines, obstacleLines[i], direction);
+                    var d = SpatialQuery.DirectionalDistance(movingEntities, obstacleEntities[i], direction);
                     if (d < distance)
                         distance = d;
                 }
@@ -157,7 +171,7 @@ namespace OpenNest.Engine.Fill
                         continue;
 
                     var gap = SpatialQuery.DirectionalGap(movingBox, obstacleBoxes[i], direction);
-                    var d = gap - partSpacing - 2 * ChordTolerance;
+                    var d = gap - partSpacing - 0.002;
                     if (d < 0) d = 0;
                     if (d < distance)
                         distance = d;

OpenNest.Engine/MultiPlateNester.cs

@@ -19,22 +19,27 @@ namespace OpenNest
     {
         private readonly Plate _template;
         private readonly List<PlateOption> _plateOptions;
+        private readonly List<PlateOption> _sortedOptions;
         private readonly double _salvageRate;
         private readonly double _minRemnantSize;
         private readonly List<PlateResult> _platePool;
         private readonly IProgress<NestProgress> _progress;
         private readonly CancellationToken _token;
+        private readonly MultiPlateNestOptions _options;
+
+        private bool HasPlateOptions => _plateOptions != null && _plateOptions.Count > 0;
 
         private MultiPlateNester(
-            Plate template, List<PlateOption> plateOptions,
+            MultiPlateNestOptions options,
-            double salvageRate, double minRemnantSize,
             List<Plate> existingPlates,
             IProgress<NestProgress> progress, CancellationToken token)
         {
-            _template = template;
+            _options = options;
-            _plateOptions = plateOptions;
+            _template = options.Template;
-            _salvageRate = salvageRate;
+            _plateOptions = options.PlateOptions;
-            _minRemnantSize = minRemnantSize;
+            _sortedOptions = options.PlateOptions?.OrderBy(o => o.Cost).ToList();
+            _salvageRate = options.SalvageRate;
+            _minRemnantSize = options.MinRemnantSize;
             _platePool = InitializePlatePool(existingPlates);
             _progress = progress;
             _token = token;
@@ -42,26 +47,31 @@ namespace OpenNest
 
         // --- Static Utility Methods ---
 
+        public static bool FitsBounds(Box container, Box part)
+        {
+            var fitsNormal = container.Width >= part.Width - Tolerance.Epsilon
+                          && container.Length >= part.Length - Tolerance.Epsilon;
+            var fitsRotated = container.Width >= part.Length - Tolerance.Epsilon
+                           && container.Length >= part.Width - Tolerance.Epsilon;
+            return fitsNormal || fitsRotated;
+        }
+
         public static List<NestItem> SortItems(List<NestItem> items, PartSortOrder sortOrder)
         {
+            var withBounds = items.Select(i => (Item: i, Bounds: i.Drawing.Program.BoundingBox())).ToList();
+
             switch (sortOrder)
             {
                 case PartSortOrder.BoundingBoxArea:
-                    return items
+                    return withBounds
-                        .OrderByDescending(i =>
+                        .OrderByDescending(x => x.Bounds.Width * x.Bounds.Length)
-                        {
+                        .Select(x => x.Item)
-                            var bb = i.Drawing.Program.BoundingBox();
-                            return bb.Width * bb.Length;
-                        })
                         .ToList();
 
                 case PartSortOrder.Size:
-                    return items
+                    return withBounds
-                        .OrderByDescending(i =>
+                        .OrderByDescending(x => System.Math.Max(x.Bounds.Width, x.Bounds.Length))
-                        {
+                        .Select(x => x.Item)
-                            var bb = i.Drawing.Program.BoundingBox();
-                            return System.Math.Max(bb.Width, bb.Length);
-                        })
                         .ToList();
 
                 default:
@@ -126,15 +136,7 @@ namespace OpenNest
 
             foreach (var option in sorted)
             {
-                var workW = option.Width - template.EdgeSpacing.Left - template.EdgeSpacing.Right;
+                if (FitsBounds(OptionWorkArea(option, template), minBounds))
-                var workL = option.Length - template.EdgeSpacing.Top - template.EdgeSpacing.Bottom;
-
-                var fitsNormal = workW >= minBounds.Width - Tolerance.Epsilon
-                              && workL >= minBounds.Length - Tolerance.Epsilon;
-                var fitsRotated = workW >= minBounds.Length - Tolerance.Epsilon
-                               && workL >= minBounds.Width - Tolerance.Epsilon;
-
-                if (fitsNormal || fitsRotated)
                 {
                     plate.Size = new Size(option.Width, option.Length);
                     return plate;
@@ -170,32 +172,47 @@ namespace OpenNest
 
         public static MultiPlateResult Nest(
             List<NestItem> items,
-            Plate template,
+            MultiPlateNestOptions options,
-            List<PlateOption> plateOptions,
+            List<Plate> existingPlates = null,
-            double salvageRate,
+            IProgress<NestProgress> progress = null,
-            PartSortOrder sortOrder,
+            CancellationToken token = default)
-            double minRemnantSize,
-            bool allowPlateCreation,
-            List<Plate> existingPlates,
-            IProgress<NestProgress> progress,
-            CancellationToken token)
         {
-            var nester = new MultiPlateNester(template, plateOptions, salvageRate,
+            var nester = new MultiPlateNester(options, existingPlates, progress, token);
-                minRemnantSize, existingPlates, progress, token);
+            return nester.Run(items, options.SortOrder, options.AllowPlateCreation);
-            return nester.Run(items, sortOrder, allowPlateCreation);
         }
 
         // --- Private Helpers ---
 
+        private static Box OptionWorkArea(PlateOption option, Plate template)
+        {
+            var w = option.Width - template.EdgeSpacing.Left - template.EdgeSpacing.Right;
+            var h = option.Length - template.EdgeSpacing.Top - template.EdgeSpacing.Bottom;
+            return new Box(0, 0, w, h);
+        }
+
         private static double ScoreZone(Box zone, Box partBounds)
         {
-            var fitsNormal = zone.Length >= partBounds.Length && zone.Width >= partBounds.Width;
+            if (!FitsBounds(zone, partBounds))
-            var fitsRotated = zone.Length >= partBounds.Width && zone.Width >= partBounds.Length;
-
-            if (!fitsNormal && !fitsRotated)
                 return -1;
 
-            return (partBounds.Length * partBounds.Width) / zone.Area();
+            var cols = (int)(zone.Width / partBounds.Width);
+            var rows = (int)(zone.Length / partBounds.Length);
+            var colsR = (int)(zone.Width / partBounds.Length);
+            var rowsR = (int)(zone.Length / partBounds.Width);
+            var estimatedCount = System.Math.Max(cols * rows, colsR * rowsR);
+
+            var utilization = (estimatedCount * partBounds.Width * partBounds.Length) / zone.Area();
+
+            var zoneAspect = zone.Width / zone.Length;
+            var partAspect = partBounds.Width / partBounds.Length;
+            var aspectMatch = System.Math.Min(zoneAspect, partAspect) / System.Math.Max(zoneAspect, partAspect);
+
+            return utilization * 0.7 + aspectMatch * 0.3;
+        }
+
+        private static void DecrementQuantity(NestItem item, int placed)
+        {
+            item.Quantity = System.Math.Max(0, item.Quantity - placed);
         }
 
         private int FillAndPlace(PlateResult pr, Box zone, NestItem item)
@@ -206,9 +223,8 @@ namespace OpenNest
 
             if (parts.Count > 0)
             {
-                pr.Plate.Parts.AddRange(parts);
+                pr.AddParts(parts);
-                pr.Parts.AddRange(parts);
+                DecrementQuantity(item, parts.Count);
-                item.Quantity = System.Math.Max(0, item.Quantity - parts.Count);
             }
 
             return parts.Count;
@@ -218,7 +234,7 @@ namespace OpenNest
         {
             var pr = new PlateResult { Plate = plate, IsNew = true };
 
-            if (_plateOptions != null)
+            if (HasPlateOptions)
             {
                 pr.ChosenSize = _plateOptions.FirstOrDefault(o =>
                     o.Width.IsEqualTo(plate.Size.Width) && o.Length.IsEqualTo(plate.Size.Length));
@@ -253,6 +269,29 @@ namespace OpenNest
             return pool;
         }
 
+        private bool TryWithUpgradedSize(PlateResult pr, PlateOption upgradeOption, Func<List<Box>, bool> tryFill)
+        {
+            var oldSize = pr.Plate.Size;
+            var oldChosenSize = pr.ChosenSize;
+
+            pr.Plate.Size = new Size(upgradeOption.Width, upgradeOption.Length);
+            pr.ChosenSize = upgradeOption;
+
+            var remnants = RemnantFinder.FromPlate(pr.Plate).FindRemnants();
+
+            if (remnants.Count > 0 && tryFill(remnants))
+                return true;
+
+            pr.Plate.Size = oldSize;
+            pr.ChosenSize = oldChosenSize;
+            return false;
+        }
+
+        private PlateOption FindSmallestFittingOption(Box partBounds)
+        {
+            return _sortedOptions?.FirstOrDefault(o => FitsBounds(OptionWorkArea(o, _template), partBounds));
+        }
+
         // --- Orchestration ---
 
         private MultiPlateResult Run(List<NestItem> items, PartSortOrder sortOrder, bool allowPlateCreation)
@@ -279,7 +318,7 @@ namespace OpenNest
                 {
                     PlaceOnNewPlates(item, bb);
 
-                    if (item.Quantity > 0 && _plateOptions != null && _plateOptions.Count > 0)
+                    if (item.Quantity > 0 && HasPlateOptions)
                         TryUpgradeOrNewPlate(item, bb);
                 }
             }
@@ -292,7 +331,7 @@ namespace OpenNest
                 CreateSharedPlates(leftovers);
             }
 
-            if (_plateOptions != null && _plateOptions.Count > 0 && !_token.IsCancellationRequested)
+            if (HasPlateOptions && !_token.IsCancellationRequested)
                 TryConsolidateTailPlates();
 
             foreach (var item in sorted.Where(i => i.Quantity > 0))
@@ -323,19 +362,26 @@ namespace OpenNest
                         break;
 
                     var engine = NestEngineRegistry.Create(pr.Plate);
-                    var cloned = remaining.Select(CloneItem).ToList();
-                    var parts = engine.PackArea(remnants[0], cloned, _progress, _token);
 
-                    if (parts.Count > 0)
+                    foreach (var remnant in remnants)
                     {
-                        pr.Plate.Parts.AddRange(parts);
+                        remaining = leftovers.Where(i => i.Quantity > 0).ToList();
-                        pr.Parts.AddRange(parts);
+                        if (remaining.Count == 0)
-                        anyPlaced = true;
+                            break;
 
-                        foreach (var item in remaining)
+                        var cloned = remaining.Select(CloneItem).ToList();
+                        var parts = engine.PackArea(remnant, cloned, _progress, _token);
+
+                        if (parts.Count > 0)
                         {
-                            var placed = parts.Count(p => p.BaseDrawing.Name == item.Drawing.Name);
+                            pr.AddParts(parts);
-                            item.Quantity = System.Math.Max(0, item.Quantity - placed);
+                            anyPlaced = true;
+
+                            foreach (var item in remaining)
+                            {
+                                var placed = parts.Count(p => p.BaseDrawing == item.Drawing);
+                                DecrementQuantity(item, placed);
+                            }
                         }
                     }
                 }
@@ -349,6 +395,7 @@ namespace OpenNest
             while (leftovers.Count > 0 && !_token.IsCancellationRequested)
             {
                 var plate = CreatePlate(_template, _plateOptions, null);
+                var pr = CreateNewPlateResult(plate);
                 var placedAny = false;
 
                 foreach (var item in leftovers)
@@ -364,22 +411,27 @@ namespace OpenNest
                         break;
 
                     var engine = NestEngineRegistry.Create(plate);
-                    var clonedItem = CloneItem(item);
-                    var parts = engine.Fill(clonedItem, remnants[0], _progress, _token);
 
-                    if (parts.Count > 0)
+                    foreach (var remnant in remnants)
                     {
-                        plate.Parts.AddRange(parts);
+                        if (item.Quantity <= 0)
-                        item.Quantity = System.Math.Max(0, item.Quantity - parts.Count);
+                            break;
-                        placedAny = true;
+
+                        var clonedItem = CloneItem(item);
+                        var parts = engine.Fill(clonedItem, remnant, _progress, _token);
+
+                        if (parts.Count > 0)
+                        {
+                            pr.AddParts(parts);
+                            DecrementQuantity(item, parts.Count);
+                            placedAny = true;
+                        }
                     }
                 }
 
                 if (!placedAny)
                     break;
 
-                var pr = CreateNewPlateResult(plate);
-                pr.Parts.AddRange(plate.Parts);
                 _platePool.Add(pr);
                 leftovers.RemoveAll(i => i.Quantity <= 0);
             }
@@ -388,6 +440,8 @@ namespace OpenNest
         private bool TryPlaceOnExistingPlates(NestItem item, Box partBounds)
         {
             var anyPlaced = false;
+            var remnantCache = new Dictionary<PlateResult, List<Box>>();
+            PlateResult lastModified = null;
 
             while (item.Quantity > 0 && !_token.IsCancellationRequested)
             {
@@ -400,14 +454,17 @@ namespace OpenNest
                     if (_token.IsCancellationRequested)
                         break;
 
-                    var workArea = pr.Plate.WorkArea();
+                    if (pr == lastModified || !remnantCache.ContainsKey(pr))
-                    var classification = Classify(partBounds, workArea);
+                    {
+                        var workArea = pr.Plate.WorkArea();
+                        var classification = Classify(partBounds, workArea);
 
-                    var remnants = classification == PartClass.Small
+                        remnantCache[pr] = classification == PartClass.Small
-                        ? FindRemnants(pr.Plate, _minRemnantSize, scrapOnly: true)
+                            ? FindRemnants(pr.Plate, _minRemnantSize, scrapOnly: true)
-                        : FindRemnants(pr.Plate, _minRemnantSize, scrapOnly: false);
+                            : FindRemnants(pr.Plate, _minRemnantSize, scrapOnly: false);
+                    }
 
-                    foreach (var zone in remnants)
+                    foreach (var zone in remnantCache[pr])
                     {
                         var score = ScoreZone(zone, partBounds);
                         if (score > bestScore)
@@ -425,6 +482,7 @@ namespace OpenNest
                 if (FillAndPlace(bestPlate, bestZone, item) == 0)
                     break;
 
+                lastModified = bestPlate;
                 anyPlaced = true;
             }
 
@@ -440,9 +498,7 @@ namespace OpenNest
                 var plate = CreatePlate(_template, _plateOptions, partBounds);
                 var workArea = plate.WorkArea();
 
-                if (partBounds.Length > workArea.Length && partBounds.Length > workArea.Width)
+                if (!FitsBounds(workArea, partBounds))
-                    break;
-                if (partBounds.Width > workArea.Width && partBounds.Width > workArea.Length)
                     break;
 
                 var pr = CreateNewPlateResult(plate);
@@ -459,36 +515,27 @@ namespace OpenNest
 
         private bool TryUpgradeOrNewPlate(NestItem item, Box partBounds)
         {
-            if (_plateOptions == null || _plateOptions.Count == 0)
+            if (!HasPlateOptions)
                 return false;
 
-            var sortedOptions = _plateOptions.OrderBy(o => o.Cost).ToList();
-
             foreach (var pr in _platePool.Where(p => p.IsNew && p.ChosenSize != null))
             {
                 var currentOption = pr.ChosenSize;
-                var currentIdx = sortedOptions.FindIndex(o =>
+                var currentIdx = _sortedOptions.FindIndex(o =>
                     o.Width.IsEqualTo(currentOption.Width) && o.Length.IsEqualTo(currentOption.Length));
 
-                if (currentIdx < 0 || currentIdx >= sortedOptions.Count - 1)
+                if (currentIdx < 0 || currentIdx >= _sortedOptions.Count - 1)
                     continue;
 
-                for (var i = currentIdx + 1; i < sortedOptions.Count; i++)
+                for (var i = currentIdx + 1; i < _sortedOptions.Count; i++)
                 {
-                    var upgradeOption = sortedOptions[i];
+                    var upgradeOption = _sortedOptions[i];
 
-                    // Only consider options that are at least as large in both dimensions.
                     if (upgradeOption.Width < currentOption.Width - Tolerance.Epsilon
                         || upgradeOption.Length < currentOption.Length - Tolerance.Epsilon)
                         continue;
 
-                    var smallestNew = sortedOptions.FirstOrDefault(o =>
+                    var smallestNew = FindSmallestFittingOption(partBounds);
-                    {
-                        var ww = o.Width - _template.EdgeSpacing.Left - _template.EdgeSpacing.Right;
-                        var wl = o.Length - _template.EdgeSpacing.Top - _template.EdgeSpacing.Bottom;
-                        return (ww >= partBounds.Width && wl >= partBounds.Length)
-                            || (ww >= partBounds.Length && wl >= partBounds.Width);
-                    });
 
                     if (smallestNew == null)
                         continue;
@@ -499,22 +546,19 @@ namespace OpenNest
 
                     if (decision.ShouldUpgrade)
                     {
-                        var oldSize = pr.Plate.Size;
+                        var placed = TryWithUpgradedSize(pr, upgradeOption, remnants =>
-                        var oldChosenSize = pr.ChosenSize;
+                        {
+                            foreach (var remnant in remnants)
+                            {
+                                if (FillAndPlace(pr, remnant, item) > 0)
+                                    return true;
+                            }
+                            return false;
+                        });
 
-                        pr.Plate.Size = new Size(upgradeOption.Width, upgradeOption.Length);
+                        if (placed)
-                        pr.ChosenSize = upgradeOption;
-
-                        var remainingArea = RemnantFinder.FromPlate(pr.Plate).FindRemnants();
-
-                        if (remainingArea.Count > 0 && FillAndPlace(pr, remainingArea[0], item) > 0)
                             return true;
-
-                        // Revert if nothing was placed.
-                        pr.Plate.Size = oldSize;
-                        pr.ChosenSize = oldChosenSize;
                     }
-                    break;
                 }
             }
 
@@ -523,73 +567,93 @@ namespace OpenNest
 
         private void TryConsolidateTailPlates()
         {
-            var activePlates = _platePool.Where(p => p.Parts.Count > 0 && p.IsNew).ToList();
+            var consolidated = true;
-            if (activePlates.Count < 2)
+            while (consolidated)
-                return;
-
-            var sortedOptions = _plateOptions.OrderBy(o => o.Cost).ToList();
-
-            // Try to absorb the smallest-utilization new plate into another plate via upgrade.
-            var donor = activePlates.OrderBy(p => p.Plate.Utilization()).First();
-            var donorParts = donor.Parts.ToList();
-
-            foreach (var target in activePlates)
             {
-                if (target == donor || target.ChosenSize == null)
+                consolidated = false;
-                    continue;
 
-                var currentOption = target.ChosenSize;
+                var activePlates = _platePool.Where(p => p.Parts.Count > 0 && p.IsNew).ToList();
+                if (activePlates.Count < 2)
+                    return;
 
-                // Try each larger option that doesn't shrink any dimension.
+                var donors = activePlates.OrderBy(p => p.Plate.Utilization()).ToList();
-                foreach (var upgradeOption in sortedOptions.Where(o =>
+
-                    o.Width >= currentOption.Width - Tolerance.Epsilon
+                foreach (var donor in donors)
-                    && o.Length >= currentOption.Length - Tolerance.Epsilon
-                    && (o.Width > currentOption.Width + Tolerance.Epsilon
-                        || o.Length > currentOption.Length + Tolerance.Epsilon)))
                 {
-                    var oldSize = target.Plate.Size;
+                    if (donor.Parts.Count == 0)
-                    var oldChosenSize = target.ChosenSize;
-
-                    target.Plate.Size = new Size(upgradeOption.Width, upgradeOption.Length);
-                    target.ChosenSize = upgradeOption;
-
-                    var remnants = RemnantFinder.FromPlate(target.Plate).FindRemnants();
-                    if (remnants.Count == 0)
-                    {
-                        target.Plate.Size = oldSize;
-                        target.ChosenSize = oldChosenSize;
                         continue;
-                    }
 
-                    // Try to pack all donor parts into the remnant space.
+                    var donorParts = donor.Parts.ToList();
-                    var engine = NestEngineRegistry.Create(target.Plate);
+                    var absorbed = false;
-                    var tempItems = donorParts
-                        .GroupBy(p => p.BaseDrawing.Name)
-                        .Select(g => new NestItem
-                        {
-                            Drawing = g.First().BaseDrawing,
-                            Quantity = g.Count(),
-                        })
-                        .ToList();
 
-                    var placed = engine.PackArea(remnants[0], tempItems, _progress, _token);
+                    foreach (var target in activePlates)
-
-                    if (placed.Count >= donorParts.Count)
                     {
-                        // All donor parts fit — absorb them.
+                        if (target == donor || target.ChosenSize == null || target.Parts.Count == 0)
-                        target.Plate.Parts.AddRange(placed);
+                            continue;
-                        target.Parts.AddRange(placed);
 
-                        foreach (var p in donorParts)
+                        var currentOption = target.ChosenSize;
-                            donor.Plate.Parts.Remove(p);
+
-                        donor.Parts.Clear();
+                        foreach (var upgradeOption in _sortedOptions.Where(o =>
-                        _platePool.Remove(donor);
+                            o.Width >= currentOption.Width - Tolerance.Epsilon
-                        return;
+                            && o.Length >= currentOption.Length - Tolerance.Epsilon
+                            && (o.Width > currentOption.Width + Tolerance.Epsilon
+                                || o.Length > currentOption.Length + Tolerance.Epsilon)))
+                        {
+                            absorbed = TryWithUpgradedSize(target, upgradeOption, remnants =>
+                            {
+                                var engine = NestEngineRegistry.Create(target.Plate);
+                                var tempItems = donorParts
+                                    .GroupBy(p => p.BaseDrawing)
+                                    .Select(g => new NestItem
+                                    {
+                                        Drawing = g.Key,
+                                        Quantity = g.Count(),
+                                    })
+                                    .ToList();
+
+                                var totalPlaced = new List<Part>();
+                                foreach (var remnant in remnants)
+                                {
+                                    var placed = engine.PackArea(remnant, tempItems, _progress, _token);
+                                    totalPlaced.AddRange(placed);
+
+                                    foreach (var ti in tempItems)
+                                    {
+                                        var count = placed.Count(p => p.BaseDrawing == ti.Drawing);
+                                        ti.Quantity = System.Math.Max(0, ti.Quantity - count);
+                                    }
+
+                                    if (tempItems.All(ti => ti.Quantity <= 0))
+                                        break;
+                                }
+
+                                if (totalPlaced.Count >= donorParts.Count)
+                                {
+                                    target.AddParts(totalPlaced);
+
+                                    foreach (var p in donorParts)
+                                        donor.Plate.Parts.Remove(p);
+                                    donor.Parts.Clear();
+                                    _platePool.Remove(donor);
+                                    return true;
+                                }
+
+                                return false;
+                            });
+
+                            if (absorbed)
+                                break;
+                        }
+
+                        if (absorbed)
+                            break;
                     }
 
-                    // Didn't fit all parts — revert.
+                    if (absorbed)
-                    target.Plate.Size = oldSize;
+                    {
-                    target.ChosenSize = oldChosenSize;
+                        consolidated = true;
+                        break;
+                    }
                 }
             }
         }

OpenNest.Engine/MultiPlateResult.cs

@@ -2,6 +2,16 @@ using System.Collections.Generic;
 
 namespace OpenNest
 {
+    public class MultiPlateNestOptions
+    {
+        public Plate Template { get; set; }
+        public List<PlateOption> PlateOptions { get; set; }
+        public double SalvageRate { get; set; } = 0.5;
+        public PartSortOrder SortOrder { get; set; } = PartSortOrder.BoundingBoxArea;
+        public double MinRemnantSize { get; set; } = 12.0;
+        public bool AllowPlateCreation { get; set; } = true;
+    }
+
     public class MultiPlateResult
     {
         public List<PlateResult> Plates { get; set; } = new();
@@ -14,5 +24,11 @@ namespace OpenNest
         public List<Part> Parts { get; set; } = new();
         public PlateOption ChosenSize { get; set; }
         public bool IsNew { get; set; }
+
+        public void AddParts(IList<Part> parts)
+        {
+            Plate.Parts.AddRange(parts);
+            Parts.AddRange(parts);
+        }
     }
 }

OpenNest.Engine/PlateProcessingResult.cs

@@ -4,7 +4,7 @@ using System.Collections.Generic;
 
 namespace OpenNest.Engine
 {
-    public class PlateResult
+    public class PlateProcessingResult
     {
         public List<ProcessedPart> Parts { get; init; }
     }

OpenNest.Engine/PlateProcessor.cs

@@ -14,7 +14,7 @@ namespace OpenNest.Engine
         public ContourCuttingStrategy CuttingStrategy { get; set; }
         public IRapidPlanner RapidPlanner { get; set; }
 
-        public PlateResult Process(Plate plate)
+        public PlateProcessingResult Process(Plate plate)
         {
             var sequenced = Sequencer.Sequence(plate.Parts.ToList(), plate);
             var results = new List<ProcessedPart>(sequenced.Count);
@@ -66,7 +66,7 @@ namespace OpenNest.Engine
                 currentPoint = ToPlateSpace(lastCutLocal, part);
             }
 
-            return new PlateResult { Parts = results };
+            return new PlateProcessingResult { Parts = results };
         }
 
         private static Vector ToPartLocal(Vector platePoint, Part part)

OpenNest.Tests/Engine/MultiPlateNesterTests.cs

@@ -229,16 +229,9 @@ public class MultiPlateNesterTests
             MakeItem("big2", 70, 35, 1),
         };
 
-        var result = MultiPlateNester.Nest(
+        var options = new MultiPlateNestOptions { Template = template };
-            items, template,
+
-            plateOptions: null,
+        var result = MultiPlateNester.Nest(items, options);
-            salvageRate: 0.5,
-            sortOrder: PartSortOrder.BoundingBoxArea,
-            minRemnantSize: 12.0,
-            allowPlateCreation: true,
-            existingPlates: null,
-            progress: null,
-            token: CancellationToken.None);
 
         // Each large part should be on its own plate.
         Assert.True(result.Plates.Count >= 2,
@@ -261,16 +254,9 @@ public class MultiPlateNesterTests
             MakeItem("tinyB", 4, 4, 3),
         };
 
-        var result = MultiPlateNester.Nest(
+        var options = new MultiPlateNestOptions { Template = template };
-            items, template,
+
-            plateOptions: null,
+        var result = MultiPlateNester.Nest(items, options);
-            salvageRate: 0.5,
-            sortOrder: PartSortOrder.BoundingBoxArea,
-            minRemnantSize: 12.0,
-            allowPlateCreation: true,
-            existingPlates: null,
-            progress: null,
-            token: CancellationToken.None);
 
         // Both small drawing types should share space — not each on their own plate.
         // With consolidation, they pack into remaining space alongside the big part.
@@ -291,16 +277,13 @@ public class MultiPlateNesterTests
             MakeItem("big2", 70, 35, 1),
         };
 
-        var result = MultiPlateNester.Nest(
+        var options = new MultiPlateNestOptions
-            items, template,
+        {
-            plateOptions: null,
+            Template = template,
-            salvageRate: 0.5,
+            AllowPlateCreation = false,
-            sortOrder: PartSortOrder.BoundingBoxArea,
+        };
-            minRemnantSize: 12.0,
+
-            allowPlateCreation: false,
+        var result = MultiPlateNester.Nest(items, options);
-            existingPlates: null,
-            progress: null,
-            token: CancellationToken.None);
 
         // No existing plates and no plate creation — nothing can be placed.
         Assert.Empty(result.Plates);
@@ -325,16 +308,10 @@ public class MultiPlateNesterTests
             MakeItem("medium", 24, 22, 1),
         };
 
-        var result = MultiPlateNester.Nest(
+        var options = new MultiPlateNestOptions { Template = template };
-            items, template,
+
-            plateOptions: null,
+        var result = MultiPlateNester.Nest(items, options,
-            salvageRate: 0.5,
+            existingPlates: new List<Plate> { existingPlate });
-            sortOrder: PartSortOrder.BoundingBoxArea,
-            minRemnantSize: 12.0,
-            allowPlateCreation: true,
-            existingPlates: new List<Plate> { existingPlate },
-            progress: null,
-            token: CancellationToken.None);
 
         // Part should be placed on the existing plate, not a new one.
         Assert.Single(result.Plates);
@@ -403,16 +380,13 @@ public class MultiPlateNesterTests
         _output.WriteLine($"Plate options: {string.Join(", ", plateOptions.Select(o => $"{o.Width}x{o.Length}"))}");
         _output.WriteLine("");
 
-        var result = MultiPlateNester.Nest(
+        var options = new MultiPlateNestOptions
-            items, template,
+        {
-            plateOptions: plateOptions,
+            Template = template,
-            salvageRate: 0.5,
+            PlateOptions = plateOptions,
-            sortOrder: PartSortOrder.BoundingBoxArea,
+        };
-            minRemnantSize: 12.0,
+
-            allowPlateCreation: true,
+        var result = MultiPlateNester.Nest(items, options);
-            existingPlates: null,
-            progress: null,
-            token: CancellationToken.None);
 
         _output.WriteLine($"=== RESULTS: {result.Plates.Count} plates ===");
 

OpenNest/Controls/ActionManager.cs

@@ -0,0 +1,118 @@
+using System;
+using System.ComponentModel;
+using Action = OpenNest.Actions.Action;
+
+namespace OpenNest.Controls
+{
+    internal class ActionManager
+    {
+        private readonly PlateView view;
+        private Action currentAction;
+        private Action previousAction;
+
+        public ActionManager(PlateView view)
+        {
+            this.view = view;
+        }
+
+        public Action CurrentAction => currentAction;
+
+        public void SetAction(Type type)
+        {
+            var action = Activator.CreateInstance(type, view) as Action;
+            if (action == null)
+                return;
+
+            if (currentAction != null)
+            {
+                if (type == typeof(Actions.ActionSelect) && !(currentAction is Actions.ActionSelect))
+                    previousAction = currentAction;
+                else
+                    previousAction = null;
+
+                currentAction.CancelAction();
+                currentAction.DisconnectEvents();
+                currentAction = null;
+            }
+
+            currentAction = action;
+            view.Status = GetDisplayName(type);
+        }
+
+        public void SetAction(Type type, params object[] args)
+        {
+            if (currentAction != null)
+            {
+                previousAction = null;
+                currentAction.CancelAction();
+                currentAction.DisconnectEvents();
+                currentAction = null;
+            }
+
+            Array.Resize(ref args, args.Length + 1);
+            for (var i = args.Length - 2; i >= 0; i--)
+                args[i + 1] = args[i];
+            args[0] = view;
+
+            var action = Activator.CreateInstance(type, args) as Action;
+            if (action == null)
+                return;
+
+            currentAction = action;
+            view.Status = GetDisplayName(type);
+        }
+
+        public void ProcessEscapeKey()
+        {
+            if (currentAction.IsBusy())
+                currentAction.CancelAction();
+            else if (currentAction is Actions.ActionSelect && previousAction != null)
+                RestorePreviousAction();
+            else
+                view.SetAction(typeof(Actions.ActionSelect));
+        }
+
+        public void RestorePreviousAction()
+        {
+            var action = previousAction;
+            previousAction = null;
+
+            currentAction.CancelAction();
+            currentAction.DisconnectEvents();
+
+            action.ConnectEvents();
+            currentAction = action;
+
+            view.Status = GetDisplayName(action.GetType());
+        }
+
+        public void OnPlateChanged()
+        {
+            if (currentAction == null || !currentAction.SurvivesPlateChange)
+                view.SetAction(typeof(Actions.ActionSelect));
+            else
+                currentAction.OnPlateChanged();
+        }
+
+        public void Cleanup()
+        {
+            if (currentAction != null)
+            {
+                currentAction.CancelAction();
+                currentAction.DisconnectEvents();
+                currentAction = null;
+            }
+        }
+
+        private string GetDisplayName(Type type)
+        {
+            var attributes = type.GetCustomAttributes(true);
+            foreach (var attr in attributes)
+            {
+                if (attr is DisplayNameAttribute displayNameAttr)
+                    return displayNameAttr.DisplayName;
+            }
+            return type.Name;
+        }
+    }
+}

OpenNest/Controls/CutOffHandler.cs

@@ -0,0 +1,81 @@
+using OpenNest.CNC;
+using OpenNest.Geometry;
+using System.Collections.Generic;
+
+namespace OpenNest.Controls
+{
+    internal class CutOffHandler
+    {
+        private readonly PlateView view;
+        private Dictionary<Part, Geometry.Entity> dragPerimeterCache;
+
+        public CutOffHandler(PlateView view)
+        {
+            this.view = view;
+        }
+
+        public bool IsDragging { get; private set; }
+
+        public CutOff TryStartDrag(Vector point, double tolerance)
+        {
+            var hitCutOff = GetCutOffAtPoint(point, tolerance);
+            if (hitCutOff == null)
+                return null;
+
+            IsDragging = true;
+            dragPerimeterCache = Plate.BuildPerimeterCache(view.Plate);
+            return hitCutOff;
+        }
+
+        public void UpdateDrag(Vector currentPoint, CutOff cutOff)
+        {
+            if (!IsDragging || cutOff == null)
+                return;
+
+            if (cutOff.Axis == CutOffAxis.Vertical)
+                cutOff.Position = new Vector(currentPoint.X, cutOff.Position.Y);
+            else
+                cutOff.Position = new Vector(cutOff.Position.X, currentPoint.Y);
+
+            cutOff.Regenerate(view.Plate, view.CutOffSettings, dragPerimeterCache);
+            view.Invalidate();
+        }
+
+        public void EndDrag()
+        {
+            if (!IsDragging)
+                return;
+
+            IsDragging = false;
+            dragPerimeterCache = null;
+            view.Plate.RegenerateCutOffs(view.CutOffSettings);
+            view.Invalidate();
+        }
+
+        public CutOff GetCutOffAtPoint(Vector point, double tolerance)
+        {
+            if (view.Plate?.CutOffs == null)
+                return null;
+
+            foreach (var cutoff in view.Plate.CutOffs)
+            {
+                var program = cutoff.Drawing?.Program;
+                if (program == null)
+                    continue;
+
+                for (var i = 0; i < program.Codes.Count - 1; i += 2)
+                {
+                    if (program.Codes[i] is RapidMove rapid &&
+                        program.Codes[i + 1] is LinearMove linear)
+                    {
+                        var line = new Line(rapid.EndPoint, linear.EndPoint);
+                        if (line.ClosestPointTo(point).DistanceTo(point) <= tolerance)
+                            return cutoff;
+                    }
+                }
+            }
+
+            return null;
+        }
+    }
+}

OpenNest/Controls/DrawingListBox.cs

@@ -152,6 +152,20 @@ namespace OpenNest.Controls
         {
             if (m.Msg == WM_ERASEBKGND)
             {
+                var itemBottom = 0;
+
+                if (Items.Count > 0)
+                {
+                    var lastVisible = System.Math.Min(TopIndex + (ClientSize.Height / ItemHeight), Items.Count - 1);
+                    itemBottom = GetItemRectangle(lastVisible).Bottom;
+                }
+
+                if (itemBottom < ClientSize.Height)
+                {
+                    using var g = Graphics.FromHdc(m.WParam);
+                    g.FillRectangle(Brushes.White, 0, itemBottom, ClientSize.Width, ClientSize.Height - itemBottom);
+                }
+
                 m.Result = (IntPtr)1;
                 return;
             }

OpenNest/Controls/PlateRenderer.cs

@@ -168,7 +168,7 @@ namespace OpenNest.Controls
                 if (program == null || program.Codes.Count == 0)
                     continue;
 
-                var activePen = cutoff == view.SelectedCutOff ? selectedPen : pen;
+                var activePen = view.Selection.SelectedCutOffs.Contains(cutoff) ? selectedPen : pen;
 
                 for (var i = 0; i < program.Codes.Count - 1; i += 2)
                 {

OpenNest/Controls/PlateView.cs

@@ -1,5 +1,4 @@
 using OpenNest.Actions;
-using OpenNest.CNC;
 using OpenNest.Collections;
 using OpenNest.Engine.Fill;
 using OpenNest.Forms;
@@ -8,7 +7,6 @@ using OpenNest.Math;
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
-using System.ComponentModel;
 using System.Diagnostics;
 using System.Drawing;
 using System.Drawing.Drawing2D;
@@ -16,31 +14,30 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Windows.Forms;
-using Action = OpenNest.Actions.Action;
 using Timer = System.Timers.Timer;
 
 namespace OpenNest.Controls
 {
     public class PlateView : DrawControl
     {
-        private readonly Font programIdFont;
         private readonly Timer redrawTimer;
 
         private string status;
         private Plate plate;
-        private Action currentAction;
+        private ActionManager actionManager;
-        private Action previousAction;
         private CutOffSettings cutOffSettings = new CutOffSettings();
-        private CutOff selectedCutOff;
+        private SelectionManager selection;
-        private bool draggingCutOff;
+        private CutOffHandler cutOffHandler;
-        private Dictionary<Part, Geometry.Entity> dragPerimeterCache;
+        private PreviewManager previewManager;
         protected List<LayoutPart> parts;
-        private List<LayoutPart> stationaryParts = new List<LayoutPart>();
-        private List<LayoutPart> activeParts = new List<LayoutPart>();
         private Point middleMouseDownPoint;
         private Box activeWorkArea;
         private List<Box> debugRemnants;
         private PlateRenderer renderer;
+        private LayoutPart hoveredPart;
+        private Point hoverPoint;
+        private bool showTooltip;
+        private Timer hoverTimer;
 
         public Box ActiveWorkArea
         {
@@ -64,13 +61,23 @@ namespace OpenNest.Controls
 
         public List<int> DebugRemnantPriorities { get; set; }
 
-        public List<LayoutPart> SelectedParts;
+        public List<LayoutPart> SelectedParts => selection.SelectedParts;
-        public ReadOnlyCollection<LayoutPart> Parts;
+        public ReadOnlyCollection<LayoutPart> Parts => new ReadOnlyCollection<LayoutPart>(parts);
+
+        internal SelectionManager Selection => selection;
+        internal CutOffHandler CutOffs => cutOffHandler;
+        internal ActionManager Actions => actionManager;
+        internal PreviewManager Previews => previewManager;
 
         public event EventHandler<ItemAddedEventArgs<Part>> PartAdded;
         public event EventHandler<ItemRemovedEventArgs<Part>> PartRemoved;
         public event EventHandler StatusChanged;
-        public event EventHandler SelectionChanged;
+
+        public event EventHandler SelectionChanged
+        {
+            add => selection.SelectionChanged += value;
+            remove => selection.SelectionChanged -= value;
+        }
 
         public PlateView()
             : this(ColorScheme.Default)
@@ -80,11 +87,11 @@ namespace OpenNest.Controls
         public PlateView(ColorScheme colorScheme)
         {
             Plate = new Plate(60, 120);
-            programIdFont = new Font(DefaultFont, FontStyle.Bold | FontStyle.Underline);
             origin = new PointF();
             parts = new List<LayoutPart>();
-            Parts = new ReadOnlyCollection<LayoutPart>(parts);
+            selection = new SelectionManager(this);
-            SelectedParts = new List<LayoutPart>();
+            cutOffHandler = new CutOffHandler(this);
+            previewManager = new PreviewManager(this);
 
             redrawTimer = new Timer()
             {
@@ -94,6 +101,9 @@ namespace OpenNest.Controls
             };
             redrawTimer.Elapsed += redrawTimer_Elapsed;
 
+            hoverTimer = new Timer() { AutoReset = false, Interval = 1000 };
+            hoverTimer.Elapsed += hoverTimer_Elapsed;
+
             SetStyle(
                 ControlStyles.AllPaintingInWmPaint |
                 ControlStyles.OptimizedDoubleBuffer |
@@ -115,7 +125,8 @@ namespace OpenNest.Controls
             DrawOffset = false;
             FillParts = true;
             renderer = new PlateRenderer(this);
-            SetAction(typeof(ActionSelect));
+            actionManager = new ActionManager(this);
+            actionManager.SetAction(typeof(ActionSelect));
 
             UpdateMatrix();
         }
@@ -148,14 +159,9 @@ namespace OpenNest.Controls
 
         internal List<LayoutPart> LayoutParts => parts;
 
-        internal IReadOnlyList<LayoutPart> PreviewParts =>
+        internal IReadOnlyList<LayoutPart> PreviewParts => previewManager.PreviewParts;
-            activeParts.Count > 0 ? activeParts : stationaryParts;
+        internal Brush PreviewBrush => previewManager.PreviewBrush;
-
+        internal Pen PreviewPen => previewManager.PreviewPen;
-        internal Brush PreviewBrush =>
-            activeParts.Count > 0 ? ColorScheme.ActivePreviewPartBrush : ColorScheme.PreviewPartBrush;
-
-        internal Pen PreviewPen =>
-            activeParts.Count > 0 ? ColorScheme.ActivePreviewPartPen : ColorScheme.PreviewPartPen;
 
         internal RectangleF GetViewBounds() =>
             new RectangleF(-origin.X, -origin.Y, Width, Height);
@@ -173,16 +179,6 @@ namespace OpenNest.Controls
             }
         }
 
-        public CutOff SelectedCutOff
-        {
-            get => selectedCutOff;
-            set
-            {
-                selectedCutOff = value;
-                Invalidate();
-            }
-        }
-
         public double RotateIncrementAngle { get; set; }
 
         public double OffsetIncrementDistance { get; set; }
@@ -200,9 +196,8 @@ namespace OpenNest.Controls
                 plate.PartAdded -= plate_PartAdded;
                 plate.PartRemoved -= plate_PartRemoved;
                 parts.Clear();
-                stationaryParts.Clear();
+                previewManager.Clear();
-                activeParts.Clear();
+                selection.Clear();
-                SelectedParts.Clear();
             }
 
             plate = p;
@@ -212,10 +207,7 @@ namespace OpenNest.Controls
             foreach (var part in plate.Parts)
                 parts.Add(LayoutPart.Create(part, this));
 
-            if (currentAction == null || !currentAction.SurvivesPlateChange)
+            actionManager?.OnPlateChanged();
-                SetAction(typeof(ActionSelect));
-            else
-                currentAction.OnPlateChanged();
         }
 
         public string Status
@@ -260,19 +252,20 @@ namespace OpenNest.Controls
             if (e.Button == MouseButtons.Middle)
                 middleMouseDownPoint = e.Location;
 
-            if (e.Button == MouseButtons.Left && currentAction is ActionSelect)
+            if (e.Button == MouseButtons.Left && actionManager.CurrentAction is ActionSelect)
             {
-                var hitCutOff = GetCutOffAtPoint(CurrentPoint, 5.0 / ViewScale);
+                var hitCutOff = cutOffHandler.TryStartDrag(CurrentPoint, 5.0 / ViewScale);
                 if (hitCutOff != null)
                 {
-                    SelectedCutOff = hitCutOff;
+                    selection.DeselectParts();
-                    draggingCutOff = true;
+                    selection.SelectedCutOffs.Clear();
-                    dragPerimeterCache = Plate.BuildPerimeterCache(Plate);
+                    selection.SelectedCutOffs.Add(hitCutOff);
+                    Invalidate();
                     return;
                 }
                 else
                 {
-                    SelectedCutOff = null;
+                    selection.DeselectCutOffs();
                 }
             }
 
@@ -288,17 +281,14 @@ namespace OpenNest.Controls
 
                 if (dx * dx + dy * dy < 25)
                 {
-                    RotateSelectedParts(Angle.ToRadians(90));
+                    selection.RotateSelectedParts(Angle.ToRadians(90));
                     Invalidate();
                 }
             }
 
-            if (draggingCutOff && selectedCutOff != null)
+            if (cutOffHandler.IsDragging && selection.SelectedCutOffs.Count > 0)
             {
-                draggingCutOff = false;
+                cutOffHandler.EndDrag();
-                dragPerimeterCache = null;
-                Plate.RegenerateCutOffs(cutOffSettings);
-                Invalidate();
                 return;
             }
 
@@ -319,7 +309,7 @@ namespace OpenNest.Controls
 
                 var angle = Angle.ToRadians((e.Delta > 0 ? -increment : increment) * multiplier);
 
-                RotateSelectedParts(angle);
+                selection.RotateSelectedParts(angle);
             }
             else
             {
@@ -358,18 +348,30 @@ namespace OpenNest.Controls
 
             lastPoint = e.Location;
 
-            if (draggingCutOff && selectedCutOff != null)
+            if (cutOffHandler.IsDragging && selection.SelectedCutOffs.Count > 0)
             {
-                if (selectedCutOff.Axis == CutOffAxis.Vertical)
+                cutOffHandler.UpdateDrag(CurrentPoint, selection.SelectedCutOffs[0]);
-                    selectedCutOff.Position = new Vector(CurrentPoint.X, selectedCutOff.Position.Y);
-                else
-                    selectedCutOff.Position = new Vector(selectedCutOff.Position.X, CurrentPoint.Y);
-
-                selectedCutOff.Regenerate(Plate, cutOffSettings, dragPerimeterCache);
-                Invalidate();
                 return;
             }
 
+            if (e.Button == MouseButtons.None && actionManager.CurrentAction is ActionSelect)
+            {
+                hoverPoint = e.Location;
+                showTooltip = false;
+                hoverTimer.Stop();
+                hoverTimer.Start();
+
+                if (hoveredPart != null)
+                    Invalidate();
+            }
+            else if (hoveredPart != null || showTooltip)
+            {
+                hoveredPart = null;
+                hoverTimer.Stop();
+                showTooltip = false;
+                Invalidate();
+            }
+
             base.OnMouseMove(e);
         }
 
@@ -386,17 +388,7 @@ namespace OpenNest.Controls
             switch (e.KeyCode)
             {
                 case Keys.Delete:
-                    if (selectedCutOff != null)
+                    selection.DeleteSelected();
-                    {
-                        Plate.CutOffs.Remove(selectedCutOff);
-                        selectedCutOff = null;
-                        Plate.RegenerateCutOffs(cutOffSettings);
-                        Invalidate();
-                    }
-                    else
-                    {
-                        RemoveSelectedParts();
-                    }
                     break;
 
                 case Keys.F:
@@ -412,15 +404,7 @@ namespace OpenNest.Controls
             }
         }
 
-        public void ProcessEscapeKey()
+        public void ProcessEscapeKey() => actionManager.ProcessEscapeKey();
-        {
-            if (currentAction.IsBusy())
-                currentAction.CancelAction();
-            else if (currentAction is ActionSelect && previousAction != null)
-                RestorePreviousAction();
-            else
-                SetAction(typeof(ActionSelect));
-        }
 
         protected override bool ProcessDialogKey(Keys keyData)
         {
@@ -440,22 +424,22 @@ namespace OpenNest.Controls
 
                 case Keys.X:
                 case Keys.Shift | Keys.Left:
-                    PushSelected(PushDirection.Left);
+                    selection.PushSelected(PushDirection.Left);
                     break;
 
                 case Keys.Shift | Keys.X:
                 case Keys.Shift | Keys.Right:
-                    PushSelected(PushDirection.Right);
+                    selection.PushSelected(PushDirection.Right);
                     break;
 
                 case Keys.Shift | Keys.Y:
                 case Keys.Shift | Keys.Up:
-                    PushSelected(PushDirection.Up);
+                    selection.PushSelected(PushDirection.Up);
                     break;
 
                 case Keys.Y:
                 case Keys.Shift | Keys.Down:
-                    PushSelected(PushDirection.Down);
+                    selection.PushSelected(PushDirection.Down);
                     break;
 
                 case Keys.Right:
@@ -496,229 +480,53 @@ namespace OpenNest.Controls
             renderer.DrawDebugRemnants(e.Graphics);
 
             base.OnPaint(e);
+
+            if (hoveredPart != null && showTooltip)
+            {
+                e.Graphics.ResetTransform();
+                var text = hoveredPart.BasePart.BaseDrawing.Name;
+                var size = e.Graphics.MeasureString(text, Font);
+                var x = hoverPoint.X + 16f;
+                var y = hoverPoint.Y - size.Height - 6f;
+
+                if (x + size.Width + 8 > ClientSize.Width)
+                    x = hoverPoint.X - size.Width - 8;
+                if (y < 0)
+                    y = hoverPoint.Y + 20;
+
+                var rect = new RectangleF(x, y, size.Width + 6, size.Height + 4);
+                using (var bgBrush = new SolidBrush(Color.FromArgb(230, Color.White)))
+                    e.Graphics.FillRectangle(bgBrush, rect);
+                e.Graphics.DrawRectangle(Pens.DimGray, rect.X, rect.Y, rect.Width, rect.Height);
+                e.Graphics.DrawString(text, Font, Brushes.Black, x + 3, y + 2);
+            }
         }
 
         protected override void OnHandleDestroyed(EventArgs e)
         {
             base.OnHandleDestroyed(e);
-
+            actionManager.Cleanup();
-            if (currentAction != null)
-            {
-                currentAction.CancelAction();
-                currentAction.DisconnectEvents();
-                currentAction = null;
-            }
         }
 
         public override void Refresh()
         {
             parts.ForEach(p => p.Update(this));
-            stationaryParts.ForEach(p => p.Update(this));
+            previewManager.Update();
-            activeParts.ForEach(p => p.Update(this));
             Invalidate();
         }
 
-        public CutOff GetCutOffAtPoint(Vector point, double tolerance)
+        public CutOff GetCutOffAtPoint(Vector point, double tolerance) => cutOffHandler.GetCutOffAtPoint(point, tolerance);
-        {
-            if (Plate?.CutOffs == null)
-                return null;
 
-            foreach (var cutoff in Plate.CutOffs)
+        public LayoutPart GetPartAtControlPoint(Point pt) => selection.GetPartAtControlPoint(pt);
-            {
+        public LayoutPart GetPartAtGraphPoint(PointF pt) => selection.GetPartAtGraphPoint(pt);
-                var program = cutoff.Drawing?.Program;
+        public LayoutPart GetPartAtPoint(Vector pt) => selection.GetPartAtPoint(pt);
-                if (program == null)
+        public IList<LayoutPart> GetPartsFromWindow(RectangleF rect, SelectionType selectionType) => selection.GetPartsFromWindow(rect, selectionType);
-                    continue;
 
-                for (var i = 0; i < program.Codes.Count - 1; i += 2)
+        public void SetAction(Type type) => actionManager.SetAction(type);
-                {
+        public void SetAction(Type type, params object[] args) => actionManager.SetAction(type, args);
-                    if (program.Codes[i] is RapidMove rapid &&
-                        program.Codes[i + 1] is LinearMove linear)
-                    {
-                        var line = new Geometry.Line(rapid.EndPoint, linear.EndPoint);
-                        if (line.ClosestPointTo(point).DistanceTo(point) <= tolerance)
-                            return cutoff;
-                    }
-                }
-            }
 
-            return null;
+        public void AlignSelected(AlignType alignType) => selection.AlignSelected(alignType);
-        }
+        public void AlignSelected(AlignType alignType, LayoutPart fixedPart) => selection.AlignSelected(alignType, fixedPart);
-
-        public LayoutPart GetPartAtControlPoint(Point pt)
-        {
-            var pt2 = PointControlToGraph(pt);
-            return GetPartAtGraphPoint(pt2);
-        }
-
-        public LayoutPart GetPartAtGraphPoint(PointF pt)
-        {
-            for (int i = parts.Count - 1; i >= 0; --i)
-            {
-                if (parts[i].Path.IsVisible(pt))
-                    return parts[i];
-            }
-
-            return null;
-        }
-
-        public LayoutPart GetPartAtPoint(Vector pt)
-        {
-            var pt2 = PointWorldToGraph(pt);
-            return GetPartAtGraphPoint(pt2);
-        }
-
-        public IList<LayoutPart> GetPartsFromWindow(RectangleF rect, SelectionType selectionType)
-        {
-            var list = new List<LayoutPart>();
-
-            if (selectionType == SelectionType.Intersect)
-            {
-                for (int i = 0; i < parts.Count; ++i)
-                {
-                    var part = parts[i];
-                    var path = part.Path;
-                    var region = new Region(path);
-
-                    if (region.IsVisible(rect))
-                        list.Add(part);
-
-                    region.Dispose();
-                }
-            }
-            else
-            {
-                for (int i = 0; i < parts.Count; ++i)
-                {
-                    var part = parts[i];
-                    var path = part.Path;
-                    var bounds = path.GetBounds();
-
-                    if (rect.Contains(bounds))
-                        list.Add(part);
-                }
-            }
-
-            return list;
-        }
-
-        public void SetAction(Type type)
-        {
-            var action = Activator.CreateInstance(type, this) as Action;
-
-            if (action == null)
-                return;
-
-            if (currentAction != null)
-            {
-                if (type == typeof(ActionSelect) && !(currentAction is ActionSelect))
-                    previousAction = currentAction;
-                else
-                    previousAction = null;
-
-                currentAction.CancelAction();
-                currentAction.DisconnectEvents();
-                currentAction = null;
-            }
-
-            currentAction = action;
-
-            Status = GetDisplayName(type);
-        }
-
-        public void SetAction(Type type, params object[] args)
-        {
-            if (currentAction != null)
-            {
-                previousAction = null;
-                currentAction.CancelAction();
-                currentAction.DisconnectEvents();
-                currentAction = null;
-            }
-
-            Array.Resize(ref args, args.Length + 1);
-
-            // shift all elements to the right
-            for (int i = args.Length - 2; i >= 0; i--)
-                args[i + 1] = args[i];
-
-            // set the first argument to this.
-            args[0] = this;
-
-            var action = Activator.CreateInstance(type, args) as Action;
-
-            if (action == null)
-                return;
-
-            currentAction = action;
-
-            Status = GetDisplayName(type);
-        }
-
-        private void RestorePreviousAction()
-        {
-            var action = previousAction;
-            previousAction = null;
-
-            currentAction.CancelAction();
-            currentAction.DisconnectEvents();
-
-            action.ConnectEvents();
-            currentAction = action;
-
-            Status = GetDisplayName(action.GetType());
-        }
-
-        public void AlignSelected(AlignType alignType)
-        {
-            if (SelectedParts.Count == 0)
-                return;
-
-            AlignSelected(alignType, SelectedParts[0]);
-        }
-
-        public void AlignSelected(AlignType alignType, LayoutPart fixedPart)
-        {
-            switch (alignType)
-            {
-                case AlignType.Bottom:
-                    Align.Bottom(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.Horizontally:
-                    Align.Horizontally(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.Left:
-                    Align.Left(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.Right:
-                    Align.Right(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.Top:
-                    Align.Top(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.Vertically:
-                    Align.Vertically(fixedPart.BasePart, SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.EvenlySpaceHorizontally:
-                    Align.EvenlyDistributeHorizontally(SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                case AlignType.EvenlySpaceVertically:
-                    Align.EvenlyDistributeVertically(SelectedParts.Select(p => p.BasePart).ToList());
-                    break;
-
-                default:
-                    return;
-            }
-
-            SelectedParts.ForEach(p => p.IsDirty = true);
-            Invalidate();
-        }
 
         public void AddPartFromDrawing(Drawing dwg, Vector location)
         {
@@ -731,51 +539,10 @@ namespace OpenNest.Controls
             Plate.Parts.Add(part);
         }
 
-        public void SetStationaryParts(List<Part> parts)
+        public void SetStationaryParts(List<Part> parts) => previewManager.SetStationaryParts(parts);
-        {
+        public void SetActiveParts(List<Part> parts) => previewManager.SetActiveParts(parts);
-            stationaryParts.Clear();
+        public void ClearPreviewParts() => previewManager.ClearPreviewParts();
-            activeParts.Clear();
+        public void AcceptPreviewParts(List<Part> parts) => previewManager.AcceptPreviewParts(parts);
-
-            if (parts != null)
-            {
-                foreach (var part in parts)
-                    stationaryParts.Add(LayoutPart.Create(part, this));
-            }
-
-            Invalidate();
-        }
-
-        public void SetActiveParts(List<Part> parts)
-        {
-            activeParts.Clear();
-
-            if (parts != null)
-            {
-                foreach (var part in parts)
-                    activeParts.Add(LayoutPart.Create(part, this));
-            }
-
-            Invalidate();
-        }
-
-        public void ClearPreviewParts()
-        {
-            stationaryParts.Clear();
-            activeParts.Clear();
-            Invalidate();
-        }
-
-        public void AcceptPreviewParts(List<Part> parts)
-        {
-            if (parts != null)
-            {
-                foreach (var part in parts)
-                    Plate.Parts.Add(part);
-            }
-
-            stationaryParts.Clear();
-            activeParts.Clear();
-        }
 
         public async void FillWithProgress(List<Part> groupParts, Box workArea)
         {
@@ -848,14 +615,7 @@ namespace OpenNest.Controls
             }
         }
 
-        public void RemoveSelectedParts()
+        public void RemoveSelectedParts() => selection.RemoveSelectedParts();
-        {
-            foreach (var part in SelectedParts)
-                Plate.Parts.Remove(part.BasePart);
-
-            DeselectAll();
-            Invalidate();
-        }
 
 
         private void redrawTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
@@ -863,6 +623,27 @@ namespace OpenNest.Controls
             Invalidate();
         }
 
+        private void hoverTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
+        {
+            var graphPt = PointControlToGraph(hoverPoint);
+            LayoutPart hitPart = null;
+            for (var i = parts.Count - 1; i >= 0; --i)
+            {
+                if (parts[i].Path.GetBounds().Contains(graphPt) &&
+                    parts[i].Path.IsVisible(graphPt))
+                {
+                    hitPart = parts[i];
+                    break;
+                }
+            }
+
+            hoveredPart = hitPart;
+            showTooltip = hitPart != null;
+
+            if (showTooltip)
+                Invalidate();
+        }
+
         private void plate_PartAdded(object sender, ItemAddedEventArgs<Part> e)
         {
             if (PartAdded != null)
@@ -880,24 +661,9 @@ namespace OpenNest.Controls
             parts.RemoveAll(p => p.BasePart == e.Item);
         }
 
-        public void DeselectAll()
+        public void DeselectAll() => selection.DeselectAll();
-        {
+        public void SelectAll() => selection.SelectAll();
-            SelectedParts.ForEach(p => p.IsSelected = false);
+        public void NotifySelectionChanged() => selection.NotifySelectionChanged();
-            SelectedParts.Clear();
-            SelectionChanged?.Invoke(this, EventArgs.Empty);
-        }
-
-        public void SelectAll()
-        {
-            parts.ForEach(p => p.IsSelected = true);
-            SelectedParts.AddRange(parts);
-            SelectionChanged?.Invoke(this, EventArgs.Empty);
-        }
-
-        public void NotifySelectionChanged()
-        {
-            SelectionChanged?.Invoke(this, EventArgs.Empty);
-        }
 
         public override void ZoomToPoint(Vector pt, float zoomFactor, bool redraw = true)
         {
@@ -930,57 +696,15 @@ namespace OpenNest.Controls
             ZoomToArea(plate.BoundingBox(false), redraw);
         }
 
-        public void PushSelected(PushDirection direction)
+        public void PushSelected(PushDirection direction) => selection.PushSelected(direction);
-        {
-            var movingParts = SelectedParts.Select(p => p.BasePart).ToList();
-            Compactor.Push(movingParts, Plate, direction);
-            SelectedParts.ForEach(p => p.IsDirty = true);
-            Invalidate();
-        }
 
-        private string GetDisplayName(Type type)
+        public void RotateSelectedParts(double angle) => selection.RotateSelectedParts(angle);
-        {
-            var attributes = type.GetCustomAttributes(true);
-
-            foreach (var attr in attributes)
-            {
-                var displayNameAttr = attr as DisplayNameAttribute;
-
-                if (displayNameAttr != null)
-                    return displayNameAttr.DisplayName;
-            }
-
-            return type.Name;
-        }
-
-        public void RotateSelectedParts(double angle)
-        {
-            var parts = SelectedParts.Select(p => p.BasePart).ToList();
-            var bounds = parts.GetBoundingBox();
-            var center = bounds.Center;
-            var anchor = bounds.Location;
-
-            for (var i = 0; i < SelectedParts.Count; ++i)
-            {
-                var part = SelectedParts[i];
-                part.BasePart.Rotate(angle, center);
-            }
-
-            var diff = anchor - parts.GetBoundingBox().Location;
-
-            for (var i = 0; i < SelectedParts.Count; ++i)
-                SelectedParts[i].Offset(diff);
-
-            if (Plate.CutOffs.Count > 0)
-                Plate.RegenerateCutOffs(cutOffSettings);
-        }
 
         protected override void UpdateMatrix()
         {
             base.UpdateMatrix();
             parts.ForEach(p => p.Update(this));
-            stationaryParts.ForEach(p => p.Update(this));
+            previewManager.Update();
-            activeParts.ForEach(p => p.Update(this));
         }
     }
 }

OpenNest/Controls/PreviewManager.cs

@@ -0,0 +1,84 @@
+using System.Collections.Generic;
+using System.Drawing;
+
+namespace OpenNest.Controls
+{
+    internal class PreviewManager
+    {
+        private readonly PlateView view;
+        private readonly List<LayoutPart> stationaryParts = new List<LayoutPart>();
+        private readonly List<LayoutPart> activeParts = new List<LayoutPart>();
+
+        public PreviewManager(PlateView view)
+        {
+            this.view = view;
+        }
+
+        public IReadOnlyList<LayoutPart> PreviewParts =>
+            activeParts.Count > 0 ? activeParts : stationaryParts;
+
+        public Brush PreviewBrush =>
+            activeParts.Count > 0 ? view.ColorScheme.ActivePreviewPartBrush : view.ColorScheme.PreviewPartBrush;
+
+        public Pen PreviewPen =>
+            activeParts.Count > 0 ? view.ColorScheme.ActivePreviewPartPen : view.ColorScheme.PreviewPartPen;
+
+        public void SetStationaryParts(List<Part> parts)
+        {
+            stationaryParts.Clear();
+            activeParts.Clear();
+
+            if (parts != null)
+            {
+                foreach (var part in parts)
+                    stationaryParts.Add(LayoutPart.Create(part, view));
+            }
+
+            view.Invalidate();
+        }
+
+        public void SetActiveParts(List<Part> parts)
+        {
+            activeParts.Clear();
+
+            if (parts != null)
+            {
+                foreach (var part in parts)
+                    activeParts.Add(LayoutPart.Create(part, view));
+            }
+
+            view.Invalidate();
+        }
+
+        public void ClearPreviewParts()
+        {
+            stationaryParts.Clear();
+            activeParts.Clear();
+            view.Invalidate();
+        }
+
+        public void AcceptPreviewParts(List<Part> parts)
+        {
+            if (parts != null)
+            {
+                foreach (var part in parts)
+                    view.Plate.Parts.Add(part);
+            }
+
+            stationaryParts.Clear();
+            activeParts.Clear();
+        }
+
+        public void Update()
+        {
+            stationaryParts.ForEach(p => p.Update(view));
+            activeParts.ForEach(p => p.Update(view));
+        }
+
+        public void Clear()
+        {
+            stationaryParts.Clear();
+            activeParts.Clear();
+        }
+    }
+}

OpenNest/Controls/SelectionManager.cs

@@ -0,0 +1,216 @@
+using OpenNest.Engine.Fill;
+using OpenNest.Geometry;
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+
+namespace OpenNest.Controls
+{
+    internal class SelectionManager
+    {
+        private readonly PlateView view;
+        private readonly List<LayoutPart> selectedParts = new List<LayoutPart>();
+        private readonly List<CutOff> selectedCutOffs = new List<CutOff>();
+
+        public SelectionManager(PlateView view)
+        {
+            this.view = view;
+        }
+
+        public List<LayoutPart> SelectedParts => selectedParts;
+        public List<CutOff> SelectedCutOffs => selectedCutOffs;
+
+        public event EventHandler SelectionChanged;
+
+        public void DeselectAll()
+        {
+            selectedParts.ForEach(p => p.IsSelected = false);
+            selectedParts.Clear();
+            selectedCutOffs.Clear();
+            SelectionChanged?.Invoke(view, EventArgs.Empty);
+        }
+
+        public void DeselectParts()
+        {
+            selectedParts.ForEach(p => p.IsSelected = false);
+            selectedParts.Clear();
+            SelectionChanged?.Invoke(view, EventArgs.Empty);
+        }
+
+        public void DeselectCutOffs()
+        {
+            selectedCutOffs.Clear();
+            view.Invalidate();
+        }
+
+        public void SelectAll()
+        {
+            var parts = view.LayoutParts;
+            parts.ForEach(p => p.IsSelected = true);
+            selectedParts.AddRange(parts);
+            SelectionChanged?.Invoke(view, EventArgs.Empty);
+        }
+
+        public void NotifySelectionChanged()
+        {
+            SelectionChanged?.Invoke(view, EventArgs.Empty);
+        }
+
+        public void DeleteSelected()
+        {
+            if (selectedCutOffs.Count > 0)
+            {
+                foreach (var cutOff in selectedCutOffs)
+                    view.Plate.CutOffs.Remove(cutOff);
+
+                selectedCutOffs.Clear();
+                view.Plate.RegenerateCutOffs(view.CutOffSettings);
+                view.Invalidate();
+            }
+            else
+            {
+                RemoveSelectedParts();
+            }
+        }
+
+        public void RemoveSelectedParts()
+        {
+            foreach (var part in selectedParts)
+                view.Plate.Parts.Remove(part.BasePart);
+
+            DeselectAll();
+            view.Invalidate();
+        }
+
+        public void AlignSelected(AlignType alignType)
+        {
+            if (selectedParts.Count == 0)
+                return;
+
+            AlignSelected(alignType, selectedParts[0]);
+        }
+
+        public void AlignSelected(AlignType alignType, LayoutPart fixedPart)
+        {
+            switch (alignType)
+            {
+                case AlignType.Bottom:
+                    Align.Bottom(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.Horizontally:
+                    Align.Horizontally(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.Left:
+                    Align.Left(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.Right:
+                    Align.Right(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.Top:
+                    Align.Top(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.Vertically:
+                    Align.Vertically(fixedPart.BasePart, selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.EvenlySpaceHorizontally:
+                    Align.EvenlyDistributeHorizontally(selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                case AlignType.EvenlySpaceVertically:
+                    Align.EvenlyDistributeVertically(selectedParts.Select(p => p.BasePart).ToList());
+                    break;
+                default:
+                    return;
+            }
+
+            selectedParts.ForEach(p => p.IsDirty = true);
+            view.Invalidate();
+        }
+
+        public void RotateSelectedParts(double angle)
+        {
+            var parts = selectedParts.Select(p => p.BasePart).ToList();
+            var bounds = parts.GetBoundingBox();
+            var center = bounds.Center;
+            var anchor = bounds.Location;
+
+            for (var i = 0; i < selectedParts.Count; ++i)
+                selectedParts[i].BasePart.Rotate(angle, center);
+
+            var diff = anchor - parts.GetBoundingBox().Location;
+
+            for (var i = 0; i < selectedParts.Count; ++i)
+                selectedParts[i].Offset(diff);
+
+            if (view.Plate.CutOffs.Count > 0)
+                view.Plate.RegenerateCutOffs(view.CutOffSettings);
+        }
+
+        public void PushSelected(PushDirection direction)
+        {
+            var movingParts = selectedParts.Select(p => p.BasePart).ToList();
+            Compactor.Push(movingParts, view.Plate, direction);
+            selectedParts.ForEach(p => p.IsDirty = true);
+            view.Invalidate();
+        }
+
+        public LayoutPart GetPartAtControlPoint(Point pt)
+        {
+            var pt2 = view.PointControlToGraph(pt);
+            return GetPartAtGraphPoint(pt2);
+        }
+
+        public LayoutPart GetPartAtGraphPoint(PointF pt)
+        {
+            var parts = view.LayoutParts;
+            for (var i = parts.Count - 1; i >= 0; --i)
+            {
+                if (parts[i].Path.IsVisible(pt))
+                    return parts[i];
+            }
+            return null;
+        }
+
+        public LayoutPart GetPartAtPoint(Vector pt)
+        {
+            var pt2 = view.PointWorldToGraph(pt);
+            return GetPartAtGraphPoint(pt2);
+        }
+
+        public IList<LayoutPart> GetPartsFromWindow(RectangleF rect, SelectionType selectionType)
+        {
+            var list = new List<LayoutPart>();
+            var parts = view.LayoutParts;
+
+            if (selectionType == SelectionType.Intersect)
+            {
+                for (var i = 0; i < parts.Count; ++i)
+                {
+                    var part = parts[i];
+                    var region = new Region(part.Path);
+                    if (region.IsVisible(rect))
+                        list.Add(part);
+                    region.Dispose();
+                }
+            }
+            else
+            {
+                for (var i = 0; i < parts.Count; ++i)
+                {
+                    var part = parts[i];
+                    var bounds = part.Path.GetBounds();
+                    if (rect.Contains(bounds))
+                        list.Add(part);
+                }
+            }
+
+            return list;
+        }
+
+        public void Clear()
+        {
+            selectedParts.Clear();
+            selectedCutOffs.Clear();
+        }
+    }
+}

OpenNest/Forms/BendLineDialog.resx

@@ -0,0 +1,120 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>

OpenNest/Forms/MainForm.cs

@@ -1006,9 +1006,18 @@ namespace OpenNest.Forms
 
                 var template = activeForm.PlateView.Plate;
 
+                var nestOptions = new MultiPlateNestOptions
+                {
+                    Template = template,
+                    PlateOptions = plateOptions,
+                    SalvageRate = salvageRate,
+                    SortOrder = sortOrder,
+                    MinRemnantSize = minRemnantSize,
+                    AllowPlateCreation = allowPlateCreation,
+                };
+
                 var result = await Task.Run(() =>
-                    MultiPlateNester.Nest(items, template, plateOptions, salvageRate,
+                    MultiPlateNester.Nest(items, nestOptions, existingPlates, progress, token));
-                        sortOrder, minRemnantSize, allowPlateCreation, existingPlates, progress, token));
 
                 foreach (var pr in result.Plates)
                 {

OpenNest/Forms/NestProgressForm.Designer.cs

@@ -427,7 +427,7 @@ namespace OpenNest.Forms
             plate1.Quantity = 0;
             previewPlateView.Plate = plate1;
             previewPlateView.RotateIncrementAngle = 10D;
-            previewPlateView.SelectedCutOff = null;
+
             previewPlateView.ShowBendLines = false;
             previewPlateView.Size = new System.Drawing.Size(356, 341);
             previewPlateView.Status = "Select";