1 | // |
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3 | // modification, are permitted provided that the following conditions |
4 | // are met: |
5 | // * Redistributions of source code must retain the above copyright |
6 | // notice, this list of conditions and the following disclaimer. |
7 | // * Redistributions in binary form must reproduce the above copyright |
8 | // notice, this list of conditions and the following disclaimer in the |
9 | // documentation and/or other materials provided with the distribution. |
10 | // * Neither the name of NVIDIA CORPORATION nor the names of its |
11 | // contributors may be used to endorse or promote products derived |
12 | // from this software without specific prior written permission. |
13 | // |
14 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY |
15 | // EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
16 | // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
17 | // PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
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20 | // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
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22 | // OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
23 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
24 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
25 | // |
26 | // Copyright (c) 2008-2021 NVIDIA Corporation. All rights reserved. |
27 | // Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved. |
28 | // Copyright (c) 2001-2004 NovodeX AG. All rights reserved. |
29 | |
30 | #ifndef PSFOUNDATION_PSHASHSET_H |
31 | #define PSFOUNDATION_PSHASHSET_H |
32 | |
33 | #include "PsHashInternals.h" |
34 | |
35 | // TODO: make this doxy-format |
36 | |
37 | // This header defines two hash sets. Hash sets |
38 | // * support custom initial table sizes (rounded up internally to power-of-2) |
39 | // * support custom static allocator objects |
40 | // * auto-resize, based on a load factor (i.e. a 64-entry .75 load factor hash will resize |
41 | // when the 49th element is inserted) |
42 | // * are based on open hashing |
43 | // |
44 | // Sets have STL-like copying semantics, and properly initialize and destruct copies of objects |
45 | // |
46 | // There are two forms of set: coalesced and uncoalesced. Coalesced sets keep the entries in the |
47 | // initial segment of an array, so are fast to iterate over; however deletion is approximately |
48 | // twice as expensive. |
49 | // |
50 | // HashSet<T>: |
51 | // bool insert(const T& k) amortized O(1) (exponential resize policy) |
52 | // bool contains(const T& k) const; O(1) |
53 | // bool erase(const T& k); O(1) |
54 | // uint32_t size() const; constant |
55 | // void reserve(uint32_t size); O(MAX(size, currentOccupancy)) |
56 | // void clear(); O(currentOccupancy) (with zero constant for objects without |
57 | // destructors) |
58 | // Iterator getIterator(); |
59 | // |
60 | // Use of iterators: |
61 | // |
62 | // for(HashSet::Iterator iter = test.getIterator(); !iter.done(); ++iter) |
63 | // myFunction(*iter); |
64 | // |
65 | // CoalescedHashSet<T> does not support getIterator, but instead supports |
66 | // const Key *getEntries(); |
67 | // |
68 | // insertion into a set already containing the element fails returning false, as does |
69 | // erasure of an element not in the set |
70 | // |
71 | |
72 | namespace physx |
73 | { |
74 | namespace shdfnd |
75 | { |
76 | template <class Key, class HashFn = Hash<Key>, class Allocator = NonTrackingAllocator> |
77 | class HashSet : public internal::HashSetBase<Key, HashFn, Allocator, false> |
78 | { |
79 | public: |
80 | typedef internal::HashSetBase<Key, HashFn, Allocator, false> HashSetBase; |
81 | typedef typename HashSetBase::Iterator Iterator; |
82 | |
83 | HashSet(uint32_t initialTableSize = 64, float loadFactor = 0.75f) : HashSetBase(initialTableSize, loadFactor) |
84 | { |
85 | } |
86 | HashSet(uint32_t initialTableSize, float loadFactor, const Allocator& alloc) |
87 | : HashSetBase(initialTableSize, loadFactor, alloc) |
88 | { |
89 | } |
90 | HashSet(const Allocator& alloc) : HashSetBase(64, 0.75f, alloc) |
91 | { |
92 | } |
93 | Iterator getIterator() |
94 | { |
95 | return Iterator(HashSetBase::mBase); |
96 | } |
97 | }; |
98 | |
99 | template <class Key, class HashFn = Hash<Key>, class Allocator = NonTrackingAllocator> |
100 | class CoalescedHashSet : public internal::HashSetBase<Key, HashFn, Allocator, true> |
101 | { |
102 | public: |
103 | typedef typename internal::HashSetBase<Key, HashFn, Allocator, true> HashSetBase; |
104 | |
105 | CoalescedHashSet(uint32_t initialTableSize = 64, float loadFactor = 0.75f) |
106 | : HashSetBase(initialTableSize, loadFactor) |
107 | { |
108 | } |
109 | |
110 | CoalescedHashSet(uint32_t initialTableSize, float loadFactor, const Allocator& alloc) |
111 | : HashSetBase(initialTableSize, loadFactor, alloc) |
112 | { |
113 | } |
114 | CoalescedHashSet(const Allocator& alloc) : HashSetBase(64, 0.75f, alloc) |
115 | { |
116 | } |
117 | |
118 | const Key* getEntries() const |
119 | { |
120 | return HashSetBase::mBase.getEntries(); |
121 | } |
122 | }; |
123 | |
124 | } // namespace shdfnd |
125 | } // namespace physx |
126 | |
127 | #endif // #ifndef PSFOUNDATION_PSHASHSET_H |
128 | |