src/rng.c


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#include "global.h"
#include "rng.h"

// The number 1103515245 comes from the example implementation of rand and srand
// in the ISO C standard.

extern u32 gRngValue;
extern u32 gRng2Value;

EWRAM_DATA static u8 sUnknown = 0;
EWRAM_DATA static u32 sRandCount = 0;

u16 Random()
{
    gRngValue = 1103515245 * gRngValue + 24691;
    sRandCount++;
    return gRngValue >> 16;
}

void SeedRng(u16 seed)
{
    gRngValue = seed;
    sUnknown = 0;
}

void SeedRng2(u16 seed)
{
    gRng2Value = seed;
}

u16 Random2(void)
{
    gRng2Value = 1103515245 * gRng2Value + 24691;
    return gRng2Value >> 16;
}