Lucene.Net  3.0.3
Lucene.Net is a port of the Lucene search engine library, written in C# and targeted at .NET runtime users.
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RecursivePrefixTreeStrategy.cs
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17 
18 using Lucene.Net.Search;
19 using Lucene.Net.Spatial.Prefix.Tree;
20 using Lucene.Net.Spatial.Queries;
21 using Spatial4n.Core.Shapes;
22 
23 namespace Lucene.Net.Spatial.Prefix
24 {
25  /// <summary>
26  /// Based on {@link RecursivePrefixTreeFilter}.
27  /// </summary>
29  {
30  private int prefixGridScanLevel;
31 
32  public RecursivePrefixTreeStrategy(SpatialPrefixTree grid, string fieldName)
33  : base(grid, fieldName)
34  {
35  prefixGridScanLevel = grid.GetMaxLevels() - 4;//TODO this default constant is dependent on the prefix grid size
36  }
37 
38  public void SetPrefixGridScanLevel(int prefixGridScanLevel)
39  {
40  //TODO if negative then subtract from maxlevels
41  this.prefixGridScanLevel = prefixGridScanLevel;
42  }
43 
44  public override Filter MakeFilter(SpatialArgs args)
45  {
46  var op = args.Operation;
47  if (op != SpatialOperation.Intersects)
48  throw new UnsupportedSpatialOperation(op);
49 
50  Shape shape = args.Shape;
51 
52  int detailLevel = grid.GetLevelForDistance(args.ResolveDistErr(ctx, distErrPct));
53 
54  return new RecursivePrefixTreeFilter(GetFieldName(), grid, shape, prefixGridScanLevel, detailLevel);
55  }
56 
57  public override string ToString()
58  {
59  return GetType().Name + "(prefixGridScanLevel:" + prefixGridScanLevel + ",SPG:(" + grid + "))";
60  }
61  }
62 }