metaforce/Runtime/CRandom16.hpp

81 lines
1.5 KiB
C++

#ifndef RETRO_CRANDOM16_HPP
#define RETRO_CRANDOM16_HPP
#include "GCNTypes.hpp"
namespace Retro
{
extern class CRandom16* GLOBAL_RANDOM;
extern class CGlobalRandom* GLOBAL_RANDOM_TOKEN;
class CRandom16
{
u32 m_seed;
public:
CRandom16(u32 p) : m_seed(p) {}
inline u32 Next()
{
m_seed = (m_seed * 0x41c64e6d) + 0x00003039;
return m_seed >> 16;
}
inline u32 GetSeed() const
{
return m_seed;
}
inline void SetSeed(u32 p)
{
m_seed = p;
}
inline float Float()
{
return Next() * 0.000015259022;
}
inline float Range(float min, float max)
{
return min + Float() * (max - min);
}
inline s32 Range(s32 min, s32 max)
{
s32 diff = max - min;
s32 rand = -1;
while (rand < 0)
rand = s32((Next() << 16) | Next());
return rand % diff + min;
}
static CRandom16* GetRandomNumber() {return GLOBAL_RANDOM;}
static void SetRandomNumber(CRandom16* rnd) {GLOBAL_RANDOM = rnd;}
};
class CGlobalRandom
{
CRandom16& m_random;
CGlobalRandom* m_prev;
public:
CGlobalRandom(CRandom16& rand)
: m_random(rand), m_prev(GLOBAL_RANDOM_TOKEN)
{
GLOBAL_RANDOM_TOKEN = this;
CRandom16::SetRandomNumber(&m_random);
}
~CGlobalRandom()
{
GLOBAL_RANDOM_TOKEN = m_prev;
if (m_prev)
CRandom16::SetRandomNumber(&m_prev->m_random);
else
CRandom16::SetRandomNumber(nullptr);
}
};
}
#endif // RETRO_CRANDOM16_HPP