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/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* ***** END GPL LICENSE BLOCK *****
*/
#ifndef __BLI_HASH_H__
#define __BLI_HASH_H__
/** \file BLI_hash.h
* \ingroup bli
*/
BLI_INLINE unsigned int BLI_hash_int_2d(unsigned int kx, unsigned int ky)
{
#define rot(x, k) (((x) << (k)) | ((x) >> (32 - (k))))
unsigned int a, b, c;
a = b = c = 0xdeadbeef + (2 << 2) + 13;
a += kx;
b += ky;
c ^= b; c -= rot(b, 14);
a ^= c; a -= rot(c, 11);
b ^= a; b -= rot(a, 25);
c ^= b; c -= rot(b, 16);
a ^= c; a -= rot(c, 4);
b ^= a; b -= rot(a, 14);
c ^= b; c -= rot(b, 24);
return c;
#undef rot
}
BLI_INLINE unsigned int BLI_hash_string(const char *str)
{
unsigned int i = 0, c;
while ((c = *str++)) {
i = i * 37 + c;
}
return i;
}
BLI_INLINE unsigned int BLI_hash_int(unsigned int k)
{
return BLI_hash_int_2d(k, 0);
}
BLI_INLINE float BLI_hash_int_01(unsigned int k)
{
return (float)BLI_hash_int(k) * (1.0f/(float)0xFFFFFFFF);
}
#endif // __BLI_HASH_H__
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