164 lines
4.3 KiB
C++
164 lines
4.3 KiB
C++
// Redistribution and use in source and binary forms, with or without
|
|
// modification, are permitted provided that the following conditions
|
|
// are met:
|
|
// * Redistributions of source code must retain the above copyright
|
|
// notice, this list of conditions and the following disclaimer.
|
|
// * Redistributions in binary form must reproduce the above copyright
|
|
// notice, this list of conditions and the following disclaimer in the
|
|
// documentation and/or other materials provided with the distribution.
|
|
// * Neither the name of NVIDIA CORPORATION nor the names of its
|
|
// contributors may be used to endorse or promote products derived
|
|
// from this software without specific prior written permission.
|
|
//
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
|
|
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
|
|
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
|
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
|
|
// OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
//
|
|
// Copyright (c) 2008-2023 NVIDIA Corporation. All rights reserved.
|
|
// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
|
|
// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
|
|
|
|
#ifndef PX_HASH_H
|
|
#define PX_HASH_H
|
|
|
|
#include "foundation/PxBasicTemplates.h"
|
|
#include "foundation/PxString.h"
|
|
|
|
#if PX_VC
|
|
#pragma warning(push)
|
|
#pragma warning(disable : 4302)
|
|
#endif
|
|
|
|
#if PX_LINUX
|
|
#include "foundation/PxSimpleTypes.h"
|
|
#endif
|
|
|
|
/*!
|
|
Central definition of hash functions
|
|
*/
|
|
|
|
#if !PX_DOXYGEN
|
|
namespace physx
|
|
{
|
|
#endif
|
|
// Hash functions
|
|
|
|
// Thomas Wang's 32 bit mix
|
|
// http://www.cris.com/~Ttwang/tech/inthash.htm
|
|
PX_FORCE_INLINE uint32_t PxComputeHash(const uint32_t key)
|
|
{
|
|
uint32_t k = key;
|
|
k += ~(k << 15);
|
|
k ^= (k >> 10);
|
|
k += (k << 3);
|
|
k ^= (k >> 6);
|
|
k += ~(k << 11);
|
|
k ^= (k >> 16);
|
|
return uint32_t(k);
|
|
}
|
|
|
|
PX_FORCE_INLINE uint32_t PxComputeHash(const int32_t key)
|
|
{
|
|
return PxComputeHash(uint32_t(key));
|
|
}
|
|
|
|
// Thomas Wang's 64 bit mix
|
|
// http://www.cris.com/~Ttwang/tech/inthash.htm
|
|
PX_FORCE_INLINE uint32_t PxComputeHash(const uint64_t key)
|
|
{
|
|
uint64_t k = key;
|
|
k += ~(k << 32);
|
|
k ^= (k >> 22);
|
|
k += ~(k << 13);
|
|
k ^= (k >> 8);
|
|
k += (k << 3);
|
|
k ^= (k >> 15);
|
|
k += ~(k << 27);
|
|
k ^= (k >> 31);
|
|
return uint32_t(UINT32_MAX & k);
|
|
}
|
|
|
|
#if PX_APPLE_FAMILY
|
|
// hash for size_t, to make gcc happy
|
|
PX_INLINE uint32_t PxComputeHash(const size_t key)
|
|
{
|
|
#if PX_P64_FAMILY
|
|
return PxComputeHash(uint64_t(key));
|
|
#else
|
|
return PxComputeHash(uint32_t(key));
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
// Hash function for pointers
|
|
PX_INLINE uint32_t PxComputeHash(const void* ptr)
|
|
{
|
|
#if PX_P64_FAMILY
|
|
return PxComputeHash(uint64_t(ptr));
|
|
#else
|
|
return PxComputeHash(uint32_t(UINT32_MAX & size_t(ptr)));
|
|
#endif
|
|
}
|
|
|
|
// Hash function for pairs
|
|
template <typename F, typename S>
|
|
PX_INLINE uint32_t PxComputeHash(const PxPair<F, S>& p)
|
|
{
|
|
uint32_t seed = 0x876543;
|
|
uint32_t m = 1000007;
|
|
return PxComputeHash(p.second) ^ (m * (PxComputeHash(p.first) ^ (m * seed)));
|
|
}
|
|
|
|
// hash object for hash map template parameter
|
|
template <class Key>
|
|
struct PxHash
|
|
{
|
|
uint32_t operator()(const Key& k) const
|
|
{
|
|
return PxComputeHash(k);
|
|
}
|
|
bool equal(const Key& k0, const Key& k1) const
|
|
{
|
|
return k0 == k1;
|
|
}
|
|
};
|
|
|
|
// specialization for strings
|
|
template <>
|
|
struct PxHash<const char*>
|
|
{
|
|
public:
|
|
uint32_t operator()(const char* _string) const
|
|
{
|
|
// "DJB" string hash
|
|
const uint8_t* string = reinterpret_cast<const uint8_t*>(_string);
|
|
uint32_t h = 5381;
|
|
for(const uint8_t* ptr = string; *ptr; ptr++)
|
|
h = ((h << 5) + h) ^ uint32_t(*ptr);
|
|
return h;
|
|
}
|
|
bool equal(const char* string0, const char* string1) const
|
|
{
|
|
return !Pxstrcmp(string0, string1);
|
|
}
|
|
};
|
|
|
|
#if !PX_DOXYGEN
|
|
} // namespace physx
|
|
#endif
|
|
|
|
#if PX_VC
|
|
#pragma warning(pop)
|
|
#endif
|
|
|
|
#endif
|
|
|