Mesh Oriented datABase  (version 5.5.0)
An array-based unstructured mesh library
RangeSeqIntersectIter.hpp
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1 /*
2  * MOAB, a Mesh-Oriented datABase, is a software component for creating,
3  * storing and accessing finite element mesh data.
4  *
5  * Copyright 2004 Sandia Corporation. Under the terms of Contract
6  * DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government
7  * retains certain rights in this software.
8  *
9  * This library is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  */
15 
16 /**\file RangeSeqIntersectIter.hpp
17  *\author Jason Kraftcheck ([email protected])
18  *\date 2006-08-11
19  *\date 2007-11-06
20  */
21 
22 #ifndef MB_RANGE_SEQ_INTERSECT_ITER_HPP
23 #define MB_RANGE_SEQ_INTERSECT_ITER_HPP
24 
25 #include "moab/Types.hpp"
26 #include "moab/Range.hpp"
27 
28 namespace moab
29 {
30 
31 class SequenceManager;
32 class EntitySequence;
33 
34 #define MB_RANGE_SEQ_INTERSECT_ITER_STATS 0
35 
36 /** \brief Iterate over the blocks of EntityHandles in an Range that
37  * are in the same EntitySequence.
38  *
39  * Iterate over an Range, returning blocks of entities that are the
40  * largest ranges of contiguous handles that meet one of the following
41  * conditions:
42  * - All are valid handles belonging to the same EntitySequence
43  * - All are invalid handles of the same EntityType
44  *
45  * The return type from init() or step() indicates whether or not the
46  * current range contains valid entities. If the handles are either
47  * all valid or all holes in an EntitySequence, that sequence can
48  * be obtained with get_sequence(). get_sequence() will return NULL if
49  * there is no corresponding EntitySequence for the block of handles.
50  *
51  * This class keeps a data related to the 'current' EntitySequence and
52  * references to the Range pasesd to init(). Changing either of these
53  * while an instance of this class is in use would be bad.
54  */
55 class RangeSeqIntersectIter
56 {
57  public:
58  RangeSeqIntersectIter( SequenceManager* sequences )
59  : mSequenceManager( sequences ), mSequence( 0 ), mStartHandle( 0 ), mEndHandle( 0 ), mLastHandle( 0 )
60  {
61  }
62 
63  /** Initialize iterator to first valid subset
64  *\return - MB_SUCCESS : initial position of iterator is valid
65  * - MB_ENITITY_NOT_FOUND : range contains invalid handle -- can step past by calling
66  *again
67  * - MB_FAILURE : No entities (start == end)
68  */
69  ErrorCode init( Range::const_iterator start, Range::const_iterator end );
70 
71  /** Step iterator to next range.
72  *\return - MB_SUCCESS : there is another range, and iter has been changed to it
73  * - MB_ENITITY_NOT_FOUND : range contains invalid handle -- can step past by calling
74  *again
75  * - MB_FAILURE : at end.
76  */
77  ErrorCode step();
78 
79  /**\brief Check if next call to step() will return MB_FAILURE.
80  *
81  * Check if the iterator cannot be advanced any further.
82  * If this method returns true, then the *next* call to step()
83  * will return MB_FAILURE.
84  */
85  bool is_at_end() const
86  {
87  return mEndHandle == mLastHandle;
88  }
89 
90  /** Get the EntitySequence for the current block.
91  * May be NULL for invaild handles.
92  */
93  EntitySequence* get_sequence() const
94  {
95  return mSequence;
96  }
97 
98  /** Get first handle in block */
99  EntityHandle get_start_handle() const
100  {
101  return mStartHandle;
102  }
103 
104  /** Get last handle in block */
105  EntityHandle get_end_handle() const
106  {
107  return mEndHandle;
108  }
109 
110 #if MB_RANGE_SEQ_INTERSECT_ITER_STATS
111  static double fragmentation()
112  {
113  return ( doubleNumCalls + intNumCalls ) / ( doubleEntCount + intEntCount );
114  }
115 #endif
116 
117  private:
118  /** Update entity sequence data (mSequence and freeIndex) for current
119  * mStartHandle. If mEndHandle is past end of sequence, trim it.
120  * Called by step() and init(). step() handles iterating over the pairs
121  * in the Range. This method handles iterating over the set of
122  * EntitySequences that intersect the pair.
123  */
124  ErrorCode update_entity_sequence();
125 
126  /** Handle error case where we encountered an EntityHandle w/out
127  * a corresponding EntitySequence. Trim mEndHandle such that it
128  * is before the next valid EntityHandle of the same type.
129  *\return Always returns MB_ENTITY_NOT_FOUND
130  */
131  ErrorCode find_invalid_range();
132 
133  SequenceManager* mSequenceManager; //!< THE EntitySequenceManager
134  EntitySequence* mSequence; //!< EntitySequence corresponding to current location
135  Range::const_pair_iterator rangeIter; //!< Current position in Range.
136  EntityHandle mStartHandle, mEndHandle; //!< Subset of current EntitySequence
137  EntityHandle mLastHandle; //!< The last of the list of all handles in the Range
138 
139 #if MB_RANGE_SEQ_INTERSECT_ITER_STATS
140  static double doubleNumCalls, doubleEntCount;
141  static unsigned long intNumCalls, intEntCount;
142  static void update_stats( unsigned long num_ents );
143 #endif
144 };
145 
146 } // namespace moab
147 
148 #endif