source: branches/HeuristicLab.BinPacking/HeuristicLab.Problems.BinPacking.2D/3.3/BinPacking2D.cs @ 14151

Last change on this file since 14151 was 14151, checked in by gkronber, 5 years ago

#1966: added abstract problem and move evaluator classes and implemented 2d bin packing problem based on integer vector encoding

File size: 9.3 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2015 Joseph Helm and 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 HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
26using HeuristicLab.Core;
27using HeuristicLab.Common;
28
29namespace HeuristicLab.Problems.BinPacking2D {
30  [Item("BinPacking2D", "Represents a single-bin packing for a 2D bin-packing problem.")]
31  [StorableClass]
32  public class BinPacking2D : BinPacking.BinPacking<PackingPosition, PackingShape, PackingItem> {
33
34    public BinPacking2D(PackingShape binMeasures)
35      : base(binMeasures) {
36      ExtremePoints = new SortedSet<PackingPosition>(new EPComparer2D());
37      ExtremePoints.Add(binMeasures.Origin);
38    }
39    [StorableConstructor]
40    protected BinPacking2D(bool deserializing) : base(deserializing) { }
41    protected BinPacking2D(BinPacking2D original, Cloner cloner)
42      : base(original, cloner) {
43      this.ExtremePoints = new SortedSet<PackingPosition>(original.ExtremePoints, new EPComparer2D());
44    }
45    public override IDeepCloneable Clone(Cloner cloner) {
46      return new BinPacking2D(this, cloner);
47    }
48
49    protected override void GenerateNewExtremePointsForNewItem(PackingItem newItem, PackingPosition position) {
50
51      int newWidth = position.Rotated ? newItem.Height : newItem.Width;
52      int newHeight = position.Rotated ? newItem.Width : newItem.Height;
53
54      //Find ExtremePoints beginning from sourcepointX
55      var sourcePointX = new PackingPosition(0, position.X + newWidth, position.Y);
56      if (sourcePointX.X < BinMeasures.Width && sourcePointX.Y < BinMeasures.Height) {
57        //Traversing down the y-axis       
58        var newPoint = new PackingPosition(0, sourcePointX.X, sourcePointX.Y - 1);
59        while (sourcePointX.Y > 0 && !IsPointOccupied(newPoint)) {
60          sourcePointX = newPoint;
61          newPoint = new PackingPosition(0, sourcePointX.X, sourcePointX.Y - 1);
62        }
63        ExtremePoints.Add(new PackingPosition(0, sourcePointX.X, sourcePointX.Y));
64      }
65
66      //Find ExtremePoints beginning from sourcepointY
67      var sourcePointY = new PackingPosition(0, position.X, position.Y + newHeight);
68      if (sourcePointY.X < BinMeasures.Width && sourcePointY.Y < BinMeasures.Height) {
69        //Traversing down the x-axis 
70        var newPoint = new PackingPosition(0, sourcePointY.X - 1, sourcePointY.Y);
71        while (sourcePointY.X > 0 && !IsPointOccupied(newPoint)) {
72          sourcePointY = newPoint;
73          newPoint = new PackingPosition(0, sourcePointY.X - 1, sourcePointY.Y);
74        }
75        ExtremePoints.Add(new PackingPosition(0, sourcePointY.X, sourcePointY.Y));
76      }
77    }
78
79    public override PackingPosition FindExtremePointForItem(PackingItem item, bool rotated, bool stackingConstraints) {
80      PackingItem rotatedItem = new PackingItem(
81        rotated ? item.Height : item.Width,
82        rotated ? item.Width : item.Height,
83        item.TargetBin);
84
85      int epIndex = 0;
86      while (epIndex < ExtremePoints.Count && (!IsPositionFeasible(rotatedItem, ExtremePoints.ElementAt(epIndex)))) { epIndex++; }
87
88      if (epIndex < ExtremePoints.Count) {
89        var currentPoint = ExtremePoints.ElementAt(epIndex);
90
91        var result = new PackingPosition(currentPoint.AssignedBin, currentPoint.X, currentPoint.Y, rotated);
92        return result;
93      }
94      return null;
95    }
96    public override PackingPosition FindPositionBySliding(PackingItem item, bool rotated) {
97      PackingPosition currentPosition = new PackingPosition(0,
98        BinMeasures.Width - (rotated ? item.Height : item.Width),
99        BinMeasures.Height - (rotated ? item.Width : item.Height), rotated);
100      //Slide the item as far as possible to the left
101      while (IsPositionFeasible(item, PackingPosition.MoveLeft(currentPosition))
102        || IsPositionFeasible(item, PackingPosition.MoveDown(currentPosition))) {
103        //Slide the item as far as possible to the bottom
104        while (IsPositionFeasible(item, PackingPosition.MoveDown(currentPosition))) {
105          currentPosition = PackingPosition.MoveDown(currentPosition);
106        }
107        if (IsPositionFeasible(item, PackingPosition.MoveLeft(currentPosition)))
108          currentPosition = PackingPosition.MoveLeft(currentPosition);
109      }
110
111      return IsPositionFeasible(item, currentPosition) ? currentPosition : null;
112    }
113
114    public override void SlidingBasedPacking(ref IList<int> sequence, IList<PackingItem> items) {
115      var temp = new List<int>(sequence);
116      for (int i = 0; i < temp.Count; i++) {
117        var item = items[temp[i]];
118        var position = FindPositionBySliding(item, false);
119        if (position != null) {
120          PackItem(temp[i], item, position);
121          sequence.Remove(temp[i]);
122        }
123      }
124    }
125    public override void SlidingBasedPacking(ref IList<int> sequence, IList<PackingItem> items, Dictionary<int, bool> rotationArray) {
126      var temp = new List<int>(sequence);
127      for (int i = 0; i < temp.Count; i++) {
128        var item = items[temp[i]];
129        var position = FindPositionBySliding(item, rotationArray[temp[i]]);
130        if (position != null) {
131          PackItem(temp[i], item, position);
132          sequence.Remove(temp[i]);
133        }
134      }
135    }
136    public override void ExtremePointBasedPacking(ref IList<int> sequence, IList<PackingItem> items, bool stackingConstraints) {
137      var temp = new List<int>(sequence);
138      foreach (int itemID in temp) {
139        var item = items[itemID];
140        var positionFound = FindExtremePointForItem(item, false, false);
141        if (positionFound != null) {
142          PackItem(itemID, item, positionFound);
143          sequence.Remove(itemID);
144        }
145      }
146    }
147    public override void ExtremePointBasedPacking(ref IList<int> sequence, IList<PackingItem> items, bool stackingConstraints, Dictionary<int, bool> rotationArray) {
148      var temp = new List<int>(sequence);
149      foreach (int itemID in temp) {
150        var item = items[itemID];
151        var positionFound = FindExtremePointForItem(item, rotationArray[itemID], false);
152        if (positionFound != null) {
153          PackItem(itemID, item, positionFound);
154          sequence.Remove(itemID);
155        }
156      }
157    }
158
159    public override int ShortestPossibleSideFromPoint(PackingPosition position) {
160      int shortestSide = int.MaxValue;
161      int width = BinMeasures.Width;
162      int height = BinMeasures.Height;
163
164      if (position.X >= width || position.Y >= height)
165        return shortestSide;
166
167      PackingPosition current = new PackingPosition(0, position.X, position.Y);
168      while (current.X < width && IsPointOccupied(current)) { current = PackingPosition.MoveRight(current); }
169      if (current.X - position.X < shortestSide)
170        shortestSide = current.X - position.X;
171
172
173      current = new PackingPosition(0, position.X, position.Y);
174      while (current.Y < height && IsPointOccupied(current)) { current = PackingPosition.MoveUp(current); }
175      if (current.Y - position.Y < shortestSide)
176        shortestSide = current.Y - position.Y;
177
178      return shortestSide;
179    }
180    public override bool IsStaticStable(PackingItem item, PackingPosition position) {
181      throw new NotSupportedException();
182    }
183
184
185    protected override void InitializeOccupationLayers() {
186      for (int i = 0; i * 10 <= BinMeasures.Width; i += 1) {
187        OccupationLayers[i] = new List<int>();
188      }
189    }
190    protected override void AddNewItemToOccupationLayers(int itemID, PackingItem measures, PackingPosition position) {
191      int x1 = position.X / 10;
192      int x2 = (position.X + (position.Rotated ? measures.Height : measures.Width)) / 10;
193
194      for (int i = x1; i <= x2; i++)
195        OccupationLayers[i].Add(itemID);
196    }
197    protected override List<int> GetLayerItemIDs(PackingPosition position) {
198      return OccupationLayers[position.X / 10];
199    }
200    protected override List<int> GetLayerItemIDs(PackingItem measures, PackingPosition position) {
201      List<int> result = new List<int>();
202      int x1 = position.X / 10;
203      int x2 = (position.X + (position.Rotated ? measures.Height : measures.Width)) / 10;
204
205      for (int i = x1; i <= x2; i++)
206        result.AddRange(OccupationLayers[i]);
207
208      return result;
209    }
210  }
211  public class EPComparer2D : IComparer<PackingPosition> {
212    public int Compare(PackingPosition a, PackingPosition b) {
213      int result = a.X.CompareTo(b.X);
214      if (result == 0)
215        result = a.Y.CompareTo(b.Y);
216
217      return result;
218    }
219  }
220}
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