virtualx-engine/core/math/random_pcg.cpp

/*************************************************************************/
/*  random_pcg.cpp                                                       */
/*************************************************************************/
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/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
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#include "random_pcg.h"

#include "core/os/os.h"

RandomPCG::RandomPCG(uint64_t p_seed, uint64_t p_inc) :
		pcg(),
		current_inc(p_inc) {
	seed(p_seed);
}

void RandomPCG::randomize() {
	seed(OS::get_singleton()->get_ticks_usec() * pcg.state + PCG_DEFAULT_INC_64);
}

double RandomPCG::random(double p_from, double p_to) {
	return randd() * (p_to - p_from) + p_from;
}

float RandomPCG::random(float p_from, float p_to) {
	return randf() * (p_to - p_from) + p_from;
}