source: branches/2817-BinPackingSpeedup/HeuristicLab.Problems.BinPacking/3.3/3D/Packer/BinPackerMinRSLeft.cs @ 15652

Last change on this file since 15652 was 15652, checked in by rhanghof, 3 years ago

#2817:

  • Little changes on the packer
File size: 13.8 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2018 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using System;
23using System.Collections.Generic;
24using System.Linq;
25using System.Text;
26using System.Threading.Tasks;
27using HeuristicLab.Common;
28using HeuristicLab.Encodings.PermutationEncoding;
29using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
30using HeuristicLab.Problems.BinPacking3D.ExtremePointCreation;
31using HeuristicLab.Problems.BinPacking3D.ExtremePointPruning;
32
33namespace HeuristicLab.Problems.BinPacking3D.Packer {
34  internal class BinPackerMinRSLeft : BinPacker {
35    #region Constructors for HEAL
36    [StorableConstructor]
37    protected BinPackerMinRSLeft(bool deserializing) : base(deserializing) { }
38
39    public BinPackerMinRSLeft(BinPackerMinRSLeft original, Cloner cloner) : base(original, cloner) {
40    }
41
42    public override IDeepCloneable Clone(Cloner cloner) {
43      return new BinPackerMinRSLeft(this, cloner);
44    }
45    #endregion
46
47
48
49    public BinPackerMinRSLeft() : base() { }
50
51    /// <summary>
52    /// This proportion of the residual space left to the item height is used for deciding if a not stackable item should be placed.
53    /// </summary>
54    private const double NOT_STACKABLE_RS_LEFT_TO_ITEM_HEIGHT_PROPORTION = 1.1;
55
56    public override IList<BinPacking3D> PackItems(Permutation sortedItems, PackingShape binShape, IList<PackingItem> items, ExtremePointCreationMethod epCreationMethod, ExtremePointPruningMethod epPruningMethod, bool useStackingConstraints) {
57      var workingItems = CloneItems(items);
58      IList<BinPacking3D> packingList = new List<BinPacking3D>();
59      IList<int> remainingIds = new List<int>(sortedItems);
60
61      try {
62        while (remainingIds.Count > 0) {
63          BinPacking3D packingBin = new BinPacking3D(binShape);
64          PackRemainingItems(ref remainingIds, ref packingBin, workingItems, epCreationMethod, useStackingConstraints);
65          packingList.Add(packingBin);         
66        }
67      } catch (BinPacking3DException e) {
68      }
69
70      ExtremePointPruningFactory.CreatePruning().PruneExtremePoints(epPruningMethod, packingList);
71
72      return packingList;
73    }
74
75
76    public override void PackItemsToPackingList(IList<BinPacking3D> packingList, Permutation sortedItems, PackingShape binShape, IList<PackingItem> items, ExtremePointCreationMethod epCreationMethod, ExtremePointPruningMethod epPruningMethod, bool useStackingConstraints) {
77      var workingItems = CloneItems(items);
78      IList<int> remainingIds = new List<int>(sortedItems);
79
80      try {
81        if (packingList.Count > 0) {
82          BinPacking3D packingBin = packingList.Last();
83          PackRemainingItems(ref remainingIds, ref packingBin, workingItems, epCreationMethod, useStackingConstraints);
84        }
85
86        while (remainingIds.Count > 0) {
87          BinPacking3D packingBin = new BinPacking3D(binShape);
88          PackRemainingItems(ref remainingIds, ref packingBin, workingItems, epCreationMethod, useStackingConstraints);
89          packingList.Add(packingBin);
90        }
91      } catch (BinPacking3DException e) {
92      }
93
94      ExtremePointPruningFactory.CreatePruning().PruneExtremePoints(epPruningMethod, packingList);
95    }
96
97    /// <summary>
98    /// Tries to pack the remainig items into a given BinPacking3D object. Each item could be packed into the BinPacking3D object will be removed from the list of remaining ids
99    /// </summary>
100    /// <param name="remainingIds">List of remaining ids. After the method has been executed the list has to have less items</param>
101    /// <param name="packingBin">This object will be filled with some of the given items</param>
102    /// <param name="items">List of packing items. Some of the items will be assigned to the BinPacking3D object</param>
103    /// <param name="epCreationMethod"></param>
104    /// <param name="useStackingConstraints"></param>
105    protected void PackRemainingItems(ref IList<int> remainingIds, ref BinPacking3D packingBin, IList<PackingItem> items, ExtremePointCreationMethod epCreationMethod, bool useStackingConstraints) {
106      IExtremePointCreator extremePointCreator = ExtremePointCreatorFactory.CreateExtremePointCreator(epCreationMethod, useStackingConstraints);
107      var remainingNotStackableItems = new List<int>();
108      foreach (var itemId in new List<int>(remainingIds)) {
109        var item = items[itemId];
110
111        // If an item is not stackable it should have a minimum waste of the residual space.
112        // As long as there are stackable items left, put the non stackable items into a collection
113        // and try to find positions where they don't waste too much space.
114        // If there are no stackable items left the non stackable have to be treated as a stackable one.
115        if (!item.IsStackabel && useStackingConstraints && remainingIds.Where(x => items[x].IsStackabel).Any()) {
116          remainingNotStackableItems.Add(itemId);         
117        } else {
118          PackingPosition position = FindPackingPositionForItem(packingBin, item, useStackingConstraints);
119          // if a valid packing position could be found, the current item can be added to the given bin
120          if (position != null) {           
121            PackItem(packingBin, itemId, item, position, extremePointCreator, useStackingConstraints);
122            remainingIds.Remove(itemId);
123          }
124        }
125
126        // try to find a valid position for a non stackable item
127        var stackableLeft = remainingIds.Where(x => items[x].IsStackabel).Any();
128        foreach (var saId in new List<int>(remainingNotStackableItems)) {
129          item = items[saId];
130          PackingPosition position = null;
131          if (stackableLeft) {
132            position  = FindPackingPositionForNotStackableItem(packingBin, item, useStackingConstraints);
133          } else {
134            position = FindPackingPositionForItem(packingBin, item, useStackingConstraints);
135          }
136         
137          if (position != null) {           
138            PackItem(packingBin, saId, item, position, extremePointCreator, useStackingConstraints);
139            remainingIds.Remove(saId);
140            remainingNotStackableItems.Remove(saId);
141          }
142        }
143       
144      }
145    }
146
147    /// <summary>
148    /// Tries to find a valid position for a non stackable item.
149    /// Positions will only be valid if the height difference of its residual space is smaller then the hight of the item.
150    /// </summary>
151    /// <param name="packingBin"></param>
152    /// <param name="packingItem"></param>
153    /// <param name="useStackingConstraints"></param>
154    /// <returns></returns>
155    private PackingPosition FindPackingPositionForNotStackableItem(BinPacking3D packingBin, PackingItem packingItem, bool useStackingConstraints) {
156      if (!CheckItemDimensions(packingBin, packingItem)) {
157        throw new BinPacking3DException($"The dimensions of the given item exceeds the bin dimensions. " +
158          $"Bin: ({packingBin.BinShape.Width} {packingBin.BinShape.Depth} {packingBin.BinShape.Height})" +
159          $"Item: ({packingItem.Width} {packingItem.Depth} {packingItem.Height})");
160      }
161      var rsds = CalculateResidalSpaceDifferences(packingBin, packingItem, useStackingConstraints).ToList();
162      var rsd = rsds.Where(x => x != null && (x.Y / (double)x.Item.Height) < NOT_STACKABLE_RS_LEFT_TO_ITEM_HEIGHT_PROPORTION).OrderByDescending(x => x.Y % x.Item.Height).FirstOrDefault();
163
164      if (rsd == null) {
165        return null;
166      }
167
168      packingItem.Rotated = rsd.Item.Rotated;
169      packingItem.Tilted = rsd.Item.Tilted;
170      return rsd.Position;
171    }
172
173    protected override PackingPosition FindPackingPositionForItem(BinPacking3D packingBin, PackingItem packingItem, bool useStackingConstraints) {
174      if (!CheckItemDimensions(packingBin, packingItem)) {
175        throw new BinPacking3DException($"The dimensions of the given item exceeds the bin dimensions. " +
176          $"Bin: ({packingBin.BinShape.Width} {packingBin.BinShape.Depth} {packingBin.BinShape.Height})" +
177          $"Item: ({packingItem.Width} {packingItem.Depth} {packingItem.Height})");
178      }
179
180      var rsd = CalculateResidalSpaceDifferences(packingBin, packingItem, useStackingConstraints).Where(x => x != null).FirstOrDefault();
181
182      if (rsd == null) {
183        return null;
184      }
185
186      packingItem.Rotated = rsd.Item.Rotated;
187      packingItem.Tilted = rsd.Item.Tilted;
188      return rsd.Position;
189    }
190
191    /// <summary>
192    ///
193    /// </summary>
194    /// <param name="packingBin"></param>
195    /// <param name="packingItem"></param>
196    /// <param name="useStackingConstraints"></param>
197    /// <returns></returns>
198    private SortedSet<ResidualSpaceDifference> CalculateResidalSpaceDifferences(BinPacking3D packingBin, PackingItem packingItem, bool useStackingConstraints) {
199      var rsds = new SortedSet<ResidualSpaceDifference>();
200
201      rsds.Add(FindResidualSpaceDifferenceForItem(packingBin, packingItem, useStackingConstraints, rotated: false, tilted: false));
202
203      if (packingItem.TiltEnabled) {
204        rsds.Add(FindResidualSpaceDifferenceForItem(packingBin, packingItem, useStackingConstraints, rotated: false, tilted: true));
205      }
206      if (packingItem.RotateEnabled) {
207        rsds.Add(FindResidualSpaceDifferenceForItem(packingBin, packingItem, useStackingConstraints, rotated: true, tilted: false));
208      }
209      if (packingItem.RotateEnabled && packingItem.TiltEnabled) {
210        rsds.Add(FindResidualSpaceDifferenceForItem(packingBin, packingItem, useStackingConstraints, rotated: true, tilted: true));
211      }
212      return rsds;
213    }
214
215    /// <summary>
216    ///
217    /// </summary>
218    /// <param name="packingBin"></param>
219    /// <param name="packingItem"></param>
220    /// <param name="useStackingConstraints"></param>
221    /// <param name="rotated"></param>
222    /// <param name="tilted"></param>
223    /// <returns></returns>
224    protected ResidualSpaceDifference FindResidualSpaceDifferenceForItem(BinPacking3D packingBin, PackingItem packingItem, bool useStackingConstraints, bool rotated, bool tilted) {
225      PackingItem newItem = new PackingItem(packingItem) {
226        Rotated = rotated,
227        Tilted = tilted
228      };
229     
230      var rsds = new SortedSet<ResidualSpaceDifference>();
231      foreach (var ep in packingBin.ExtremePoints) {
232        var position = ep.Key;
233        foreach (var rs in ep.Value) {
234          var rsd = ResidualSpaceDifference.Create(position, newItem, rs);
235          if (rsd != null) {
236            rsds.Add(rsd);
237          }
238        }
239      }
240      return rsds.Where(rsd => packingBin.IsPositionFeasible(rsd.Item, rsd.Position, useStackingConstraints)).FirstOrDefault();
241    }
242       
243    protected override bool CheckItemDimensions(BinPacking3D packingBin, PackingItem item) {
244      bool ok = false;
245      int width = item.OriginalWidth;
246      int height = item.OriginalHeight;
247      int depth = item.OriginalDepth;
248
249      ok |= CheckItemDimensions(packingBin, width, height, depth);
250
251      if (item.RotateEnabled && item.TiltEnabled) {
252        ok |= CheckItemDimensions(packingBin, depth, height, width);//rotated
253        ok |= CheckItemDimensions(packingBin, height, width, depth);//tilted
254        ok |= CheckItemDimensions(packingBin, depth, width, height);//rotated & tilted
255      } else if (item.RotateEnabled) {
256        ok |= CheckItemDimensions(packingBin, depth, height, width);
257      } else if (item.TiltEnabled) {
258        ok |= CheckItemDimensions(packingBin, height, width, depth);
259      }
260
261      return ok;
262    }
263
264    private bool CheckItemDimensions(BinPacking3D packingBin, int width, int height, int depth) {
265      return base.CheckItemDimensions(packingBin, new PackingItem() {
266        OriginalWidth = width,
267        OriginalHeight = height,
268        OriginalDepth = depth
269      });
270    }
271
272   
273    protected class ResidualSpaceDifference : IComparable {
274      public static ResidualSpaceDifference Create(PackingPosition position, PackingItem item, ResidualSpace rs) {
275        var x = rs.Width - item.Width;
276        var y = rs.Height - item.Height;
277        var z = rs.Depth - item.Depth;
278        // the item can't be places in the residual space
279        if (rs.IsZero() || x < 0 || y < 0 || z < 0) {
280          return null;
281        }
282
283        return new ResidualSpaceDifference() {
284          Position = position,
285          Item = item,
286          X = x,
287          Y = y,
288          Z = z
289        };
290      }
291
292      public ResidualSpaceDifference() { }
293
294      public PackingItem Item { get; set; }
295
296      public PackingPosition Position { get; set; }
297      public int X { get; set; }
298      public int Y { get; set; }
299      public int Z { get; set; }
300
301
302      public int CompareTo(object obj) {
303        if (!(obj is ResidualSpaceDifference)) {
304          return 0;
305        }
306        var rsd = obj as ResidualSpaceDifference;
307
308        var x = this.X - rsd.X;
309        var y = rsd.Y - this.Y;
310        var z = this.Z - rsd.Z;
311
312        if (x != 0) {
313          return x;
314        } else if (y != 0) {
315          return y;
316        } else if (z != 0) {
317          return z;
318        }
319
320        return 0;
321      }
322    }
323
324  }
325}
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