oakfield/sim__seed_8h_source.html

#ifndef OAKFIELD_SIM_SEED_H

#define OAKFIELD_SIM_SEED_H


#include <stdint.h>


#ifdef __cplusplus

extern "C" {

#endif


#define SIM_SEED_DEFAULT 0xA5A5A5A5A5A5A5A5ULL


uint64_t sim_seed_normalize(uint64_t seed);


uint64_t sim_seed_mix64(uint64_t value);


uint64_t sim_seed_tag(const char *tag);


uint64_t sim_seed_derive(uint64_t base_seed, uint64_t tag_hash, uint64_t index);


void sim_seed_stream(uint64_t base_seed, const char *tag, uint64_t index, uint64_t *out_state,

                     uint64_t *out_inc);


#ifdef __cplusplus

}

#endif


#endif /* OAKFIELD_SIM_SEED_H */

sim_seed_derive
uint64_t sim_seed_derive(uint64_t base_seed, uint64_t tag_hash, uint64_t index)
Derive a deterministic seed from a base seed, tag hash, and index.

sim_seed_normalize
uint64_t sim_seed_normalize(uint64_t seed)
Normalize a seed (zero maps to SIM_SEED_DEFAULT).

sim_seed_mix64
uint64_t sim_seed_mix64(uint64_t value)
Mix a 64-bit value into a high-quality hash.

sim_seed_tag
uint64_t sim_seed_tag(const char *tag)
Hash a domain tag into a 64-bit value.

sim_seed_stream
void sim_seed_stream(uint64_t base_seed, const char *tag, uint64_t index, uint64_t *out_state, uint64_t *out_inc)
Derive a PCG32 stream (state + increment) from a base seed and domain tag.