nuclear@0: /* nuclear@0: Open Asset Import Library (assimp) nuclear@0: ---------------------------------------------------------------------- nuclear@0: nuclear@0: Copyright (c) 2006-2012, assimp team nuclear@0: All rights reserved. nuclear@0: nuclear@0: Redistribution and use of this software in source and binary forms, nuclear@0: with or without modification, are permitted provided that the nuclear@0: following conditions are met: nuclear@0: nuclear@0: * Redistributions of source code must retain the above nuclear@0: copyright notice, this list of conditions and the nuclear@0: following disclaimer. nuclear@0: nuclear@0: * Redistributions in binary form must reproduce the above nuclear@0: copyright notice, this list of conditions and the nuclear@0: following disclaimer in the documentation and/or other nuclear@0: materials provided with the distribution. nuclear@0: nuclear@0: * Neither the name of the assimp team, nor the names of its nuclear@0: contributors may be used to endorse or promote products nuclear@0: derived from this software without specific prior nuclear@0: written permission of the assimp team. nuclear@0: nuclear@0: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS nuclear@0: "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT nuclear@0: LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR nuclear@0: A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT nuclear@0: OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, nuclear@0: SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT nuclear@0: LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, nuclear@0: DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY nuclear@0: THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT nuclear@0: (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE nuclear@0: OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. nuclear@0: nuclear@0: ---------------------------------------------------------------------- nuclear@0: */ nuclear@0: nuclear@0: #ifndef AI_HASH_H_INCLUDED nuclear@0: #define AI_HASH_H_INCLUDED nuclear@0: nuclear@0: // ------------------------------------------------------------------------------------------------ nuclear@0: // Hashing function taken from nuclear@0: // http://www.azillionmonkeys.com/qed/hash.html nuclear@0: // (incremental version) nuclear@0: // nuclear@0: // This code is Copyright 2004-2008 by Paul Hsieh. It is used here in the belief that nuclear@0: // Assimp's license is considered compatible with Pauls's derivative license as specified nuclear@0: // on his web page. nuclear@0: // nuclear@0: // (stdint.h should have been been included here) nuclear@0: // ------------------------------------------------------------------------------------------------ nuclear@0: #undef get16bits nuclear@0: #if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \ nuclear@0: || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__) nuclear@0: #define get16bits(d) (*((const uint16_t *) (d))) nuclear@0: #endif nuclear@0: nuclear@0: #if !defined (get16bits) nuclear@0: #define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)\ nuclear@0: +(uint32_t)(((const uint8_t *)(d))[0]) ) nuclear@0: #endif nuclear@0: nuclear@0: // ------------------------------------------------------------------------------------------------ nuclear@0: inline uint32_t SuperFastHash (const char * data, uint32_t len = 0, uint32_t hash = 0) { nuclear@0: uint32_t tmp; nuclear@0: int rem; nuclear@0: nuclear@0: if (!data) return 0; nuclear@0: if (!len)len = (uint32_t)::strlen(data); nuclear@0: nuclear@0: rem = len & 3; nuclear@0: len >>= 2; nuclear@0: nuclear@0: /* Main loop */ nuclear@0: for (;len > 0; len--) { nuclear@0: hash += get16bits (data); nuclear@0: tmp = (get16bits (data+2) << 11) ^ hash; nuclear@0: hash = (hash << 16) ^ tmp; nuclear@0: data += 2*sizeof (uint16_t); nuclear@0: hash += hash >> 11; nuclear@0: } nuclear@0: nuclear@0: /* Handle end cases */ nuclear@0: switch (rem) { nuclear@0: case 3: hash += get16bits (data); nuclear@0: hash ^= hash << 16; nuclear@0: hash ^= data[sizeof (uint16_t)] << 18; nuclear@0: hash += hash >> 11; nuclear@0: break; nuclear@0: case 2: hash += get16bits (data); nuclear@0: hash ^= hash << 11; nuclear@0: hash += hash >> 17; nuclear@0: break; nuclear@0: case 1: hash += *data; nuclear@0: hash ^= hash << 10; nuclear@0: hash += hash >> 1; nuclear@0: } nuclear@0: nuclear@0: /* Force "avalanching" of final 127 bits */ nuclear@0: hash ^= hash << 3; nuclear@0: hash += hash >> 5; nuclear@0: hash ^= hash << 4; nuclear@0: hash += hash >> 17; nuclear@0: hash ^= hash << 25; nuclear@0: hash += hash >> 6; nuclear@0: nuclear@0: return hash; nuclear@0: } nuclear@0: nuclear@0: #endif // !! AI_HASH_H_INCLUDED