Faster code possible?

[ShaChris23]

Hi,

What's the fastest way to extract the sign bit of a floating point value and put it into the sign bit of a 16-bit value?

We are trying to pack a

1) signed float
2) 1-bit value

into a 16-bit value.

The format is as followed:

16th bit (MSB): sign
15th - 1st bit: value (+/- 128)
0th bit (LSB): quality bit


Below is the code that I have; cant think of any other way to make it faster.
We are trying to minimize the use of an if statement. Any suggestions/comments would be greatly appreciated:

#include <math.h>
 
typedef enum
{
  BAD, 
  GOOD
} BathyQuality;
 
class BathyAngle
{
public:
  float Angle();
  BathyQuality Quality();
 
public:
  void SetAngle( float data );
  void SetQuality( BathyQuality quality );
 
private:
  short mData;
};
 
 
 
inline float BathyAngle::Angle()
{
  if (mData < 0)
    return ((mData & 0x7FFF) >> 1) / -128.0f;
  else
    return ((mData & 0x7FFF) >> 1) / 128.0f;
}
inline BathyQuality BathyAngle::Quality()
{
  return static_cast< BathyQuality >( mData & 0x01 );
}
 
inline void BathyAngle::SetAngle( float data )
{  
  mData &= 0x1;
 
  mData |= ( static_cast< short > ( fabs(data) * 128.0f ) ) << 1;
 
  if( data < 0.0f )
  {
    mData |= 0x8000;
  }
  else
  {
    mData &= ~0x8000;
  }
}
inline void BathyAngle::SetQuality( BathyQuality quality )
{ 
  if( quality == GOOD )
    mData |= GOOD;
  else  
    mData &= ~GOOD;
}

#include <math.h>

typedef enum
{
  BAD, 
  GOOD
} BathyQuality;

class BathyAngle
{
public:
  float Angle();
  BathyQuality Quality();

public:
  void SetAngle( float data );
  void SetQuality( BathyQuality quality );

private:
  short mData;
};



inline float BathyAngle::Angle()
{
  if (mData < 0)
    return ((mData & 0x7FFF) >> 1) / -128.0f;
  else
    return ((mData & 0x7FFF) >> 1) / 128.0f;
}
inline BathyQuality BathyAngle::Quality()
{
  return static_cast< BathyQuality >( mData & 0x01 );
}

inline void BathyAngle::SetAngle( float data )
{  
  mData &= 0x1;

  mData |= ( static_cast< short > ( fabs(data) * 128.0f ) ) << 1;

  if( data < 0.0f )
  {
    mData |= 0x8000;
  }
  else
  {
    mData &= ~0x8000;
  }
}
inline void BathyAngle::SetQuality( BathyQuality quality )
{ 
  if( quality == GOOD )
    mData |= GOOD;
  else  
    mData &= ~GOOD;
}

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[wysota]

Have you tried using bit fields?