35 lines
649 B
C
35 lines
649 B
C
#pragma once
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#include <stdint.h>
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#include "misc_utils.h"
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typedef struct {
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uint32_t state;
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} RandomEngine;
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static void RandomEngine_init(RandomEngine* self) {
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self->state = 0x6d2b79f5u;
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}
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static uint32_t RandomEngine_rnd(RandomEngine* self) {
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uint32_t x = self->state;
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if (x == 0) {
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x = 0x6d2b79f5u;
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}
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x ^= x << 13;
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x ^= x >> 17;
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x ^= x << 5;
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x = x * 1664525u + 1013904223u;
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self->state = x;
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return x;
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}
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static uint32_t RandomEngine_rnd_interval(
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RandomEngine* self, uint32_t from, uint32_t until) {
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check(from < until);
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return from + RandomEngine_rnd(self) % (until - from);
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}
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