1//
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3// modification, are permitted provided that the following conditions
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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
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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_PSHASHMAP_H
31#define PSFOUNDATION_PSHASHMAP_H
32
33#include "PsHashInternals.h"
34
35// TODO: make this doxy-format
36//
37// This header defines two hash maps. Hash maps
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// * have O(1) contains, erase
44//
45// Maps have STL-like copying semantics, and properly initialize and destruct copies of objects
46//
47// There are two forms of map: coalesced and uncoalesced. Coalesced maps keep the entries in the
48// initial segment of an array, so are fast to iterate over; however deletion is approximately
49// twice as expensive.
50//
51// HashMap<T>:
52// bool insert(const Key& k, const Value& v) O(1) amortized (exponential resize policy)
53// Value & operator[](const Key& k) O(1) for existing objects, else O(1) amortized
54// const Entry * find(const Key& k); O(1)
55// bool erase(const T& k); O(1)
56// uint32_t size(); constant
57// void reserve(uint32_t size); O(MAX(currentOccupancy,size))
58// void clear(); O(currentOccupancy) (with zero constant for objects
59// without
60// destructors)
61// Iterator getIterator();
62//
63// operator[] creates an entry if one does not exist, initializing with the default constructor.
64// CoalescedHashMap<T> does not support getIterator, but instead supports
65// const Key *getEntries();
66//
67// Use of iterators:
68//
69// for(HashMap::Iterator iter = test.getIterator(); !iter.done(); ++iter)
70// myFunction(iter->first, iter->second);
71
72namespace physx
73{
74namespace shdfnd
75{
76template <class Key, class Value, class HashFn = Hash<Key>, class Allocator = NonTrackingAllocator>
77class HashMap : public internal::HashMapBase<Key, Value, HashFn, Allocator>
78{
79 public:
80 typedef internal::HashMapBase<Key, Value, HashFn, Allocator> HashMapBase;
81 typedef typename HashMapBase::Iterator Iterator;
82
83 HashMap(uint32_t initialTableSize = 64, float loadFactor = 0.75f) : HashMapBase(initialTableSize, loadFactor)
84 {
85 }
86 HashMap(uint32_t initialTableSize, float loadFactor, const Allocator& alloc)
87 : HashMapBase(initialTableSize, loadFactor, alloc)
88 {
89 }
90 HashMap(const Allocator& alloc) : HashMapBase(64, 0.75f, alloc)
91 {
92 }
93 Iterator getIterator()
94 {
95 return Iterator(HashMapBase::mBase);
96 }
97};
98
99template <class Key, class Value, class HashFn = Hash<Key>, class Allocator = NonTrackingAllocator>
100class CoalescedHashMap : public internal::HashMapBase<Key, Value, HashFn, Allocator>
101{
102 public:
103 typedef internal::HashMapBase<Key, Value, HashFn, Allocator> HashMapBase;
104
105 CoalescedHashMap(uint32_t initialTableSize = 64, float loadFactor = 0.75f)
106 : HashMapBase(initialTableSize, loadFactor)
107 {
108 }
109 const Pair<const Key, Value>* getEntries() const
110 {
111 return HashMapBase::mBase.getEntries();
112 }
113};
114
115} // namespace shdfnd
116} // namespace physx
117
118#endif // #ifndef PSFOUNDATION_PSHASHMAP_H
119

source code of qtquick3dphysics/src/3rdparty/PhysX/source/foundation/include/PsHashMap.h