62 lines
2.5 KiB
C
62 lines
2.5 KiB
C
|
/* BSD 3-Clause License
|
||
|
|
*
|
||
|
|
* Copyright © 2008-2022, Jice and the libtcod contributors.
|
||
|
|
* All rights reserved.
|
||
|
|
*
|
||
|
|
* Redistribution and use in source and binary forms, with or without
|
||
|
|
* modification, are permitted provided that the following conditions are met:
|
||
|
|
*
|
||
|
|
* 1. Redistributions of source code must retain the above copyright notice,
|
||
|
|
* this list of conditions and the following disclaimer.
|
||
|
|
*
|
||
|
|
* 2. 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.
|
||
|
|
*
|
||
|
|
* 3. Neither the name of the copyright holder 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 AND CONTRIBUTORS "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 HOLDER 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.
|
||
|
|
*/
|
||
|
|
#ifndef LIBTCOD_RANDOM_H_
|
||
|
|
#define LIBTCOD_RANDOM_H_
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
#include "config.h"
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
extern "C" {
|
||
|
|
#endif // __cplusplus
|
||
|
|
/**
|
||
|
|
Return the next random uint64_t from a SplitMix64 generator.
|
||
|
|
|
||
|
|
`state[1]` is a non-NULL pointer to the internal state of the generator.
|
||
|
|
There is no initializer function because the first value of `state[1]` is
|
||
|
|
itself the seed which can start at any value.
|
||
|
|
`state[1]` will be updated by this call.
|
||
|
|
|
||
|
|
This function is provisional and may change.
|
||
|
|
*/
|
||
|
|
static inline uint64_t TCOD_rng_splitmix64_next(uint64_t* state) {
|
||
|
|
// Based on http://xoshiro.di.unimi.it/splitmix64.c
|
||
|
|
uint64_t z = (*state += 0x9e3779b97f4a7c15);
|
||
|
|
z = (z ^ (z >> 30)) * 0xbf58476d1ce4e5b9;
|
||
|
|
z = (z ^ (z >> 27)) * 0x94d049bb133111eb;
|
||
|
|
return z ^ (z >> 31);
|
||
|
|
}
|
||
|
|
#ifdef __cplusplus
|
||
|
|
} // extern "C"
|
||
|
|
#endif // __cplusplus
|
||
|
|
#endif // LIBTCOD_RANDOM_H_
|