primedev/core/math/bits.cpp


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//=============================================================================//
//
// Purpose: look for NANs, infinities, and underflows.
//
//=============================================================================//

#include "bits.h"

//-----------------------------------------------------------------------------
// This follows the ANSI/IEEE 754-1985 standard
//-----------------------------------------------------------------------------
unsigned long& FloatBits(float& f)
{
	return *reinterpret_cast<unsigned long*>(&f);
}

unsigned long const& FloatBits(float const& f)
{
	return *reinterpret_cast<unsigned long const*>(&f);
}

float BitsToFloat(unsigned long i)
{
	return *reinterpret_cast<float*>(&i);
}

bool IsFinite(float f)
{
	return ((FloatBits(f) & 0x7F800000) != 0x7F800000);
}

unsigned long FloatAbsBits(float f)
{
	return FloatBits(f) & 0x7FFFFFFF;
}

float FloatMakePositive(float f)
{
	return fabsf(f);
}

float FloatNegate(float f)
{
	return -f; // BitsToFloat( FloatBits(f) ^ 0x80000000 );
}