G4SurfBits Class Reference

G4SurfBits provides a simple container of bits, to be used for optimization of tessellated surfaces. The size of the container is automatically extended when a bit number is either set or tested. More...

#include <G4SurfBits.hh>

Public Member Functions
	G4SurfBits (unsigned int nbits=0)
	~G4SurfBits ()
	G4SurfBits (const G4SurfBits &)
G4SurfBits &	operator= (const G4SurfBits &)
void	ResetAllBits (G4bool value=false)
void	ResetBitNumber (unsigned int bitnumber)
void	SetBitNumber (unsigned int bitnumber, G4bool value=true)
G4bool	TestBitNumber (unsigned int bitnumber) const
G4bool	operator[] (unsigned int bitnumber) const
void	set (unsigned int nbits, const char *array)
void	set (unsigned int nbits, const G4int *array)
void	Get (char *array) const
void	Get (G4int *array) const
void	Clear ()
void	Compact ()
unsigned int	GetNbits () const
unsigned int	GetNbytes () const
void	Print () const
void	Output (std::ostream &) const

Public Attributes
unsigned char *	fAllBits = nullptr

Detailed Description

G4SurfBits provides a simple container of bits, to be used for optimization of tessellated surfaces. The size of the container is automatically extended when a bit number is either set or tested.

Definition at line 56 of file G4SurfBits.hh.

Constructor & Destructor Documentation

G4SurfBits() [1/2]

G4SurfBits::G4SurfBits

(

unsigned int

nbits = 0

)

Constructor given the number of bits.

Parameters

[in]

nbits

The number of bits.

Definition at line 35 of file G4SurfBits.cc.

                                         : fNBits(nBits)
{
  // G4SurfBits constructor.  All bits set to 0
 
  if (fNBits <= 0) { fNBits = 0; }
  fNBytes  = fNBits != 0u ? ((fNBits-1)/8) + 1 : 1;
  fAllBits = new unsigned char[fNBytes];
  // this is redundant only with libNew
  std::memset(fAllBits,0,fNBytes);
}

Referenced by G4SurfBits(), and operator=().

~G4SurfBits()

G4SurfBits::~G4SurfBits

(

)

Destructor. Clears all allocated bits.

Definition at line 80 of file G4SurfBits.cc.

{
  // G4SurfBits destructor
 
  delete [] fAllBits;
}

G4SurfBits() [2/2]

G4SurfBits::G4SurfBits

(

const G4SurfBits &

original

)

Copy constructor and assignment operator.

Definition at line 47 of file G4SurfBits.cc.

  : fNBits(original.fNBits), fNBytes(original.fNBytes)
{
  // G4SurfBits copy constructor
 
  fAllBits = new unsigned char[fNBytes];
  std::memcpy(fAllBits,original.fAllBits,fNBytes);
}

Member Function Documentation

Clear()

void G4SurfBits::Clear

(

)

Utilities to clear or reduce the space used.

Definition at line 88 of file G4SurfBits.cc.

{
  // Clear the value.
 
  delete [] fAllBits;
  fAllBits = nullptr;
  fNBits   = 0;
  fNBytes  = 0;
}

Compact()

void G4SurfBits::Compact

(

)

Definition at line 99 of file G4SurfBits.cc.

{
  // Reduce the storage used by the object to a minimun
 
  if ((fNBits == 0u) || (fAllBits == nullptr)) { return; }
  unsigned int needed;
  for(needed=fNBytes-1; needed > 0 && fAllBits[needed]==0; ) { --needed; }
  ++needed;
 
  if (needed!=fNBytes)
  {
    unsigned char* old_location = fAllBits;
    fAllBits = new unsigned char[needed];
 
    std::memcpy(fAllBits,old_location,needed);
    delete [] old_location;
 
    fNBytes = needed;
    fNBits = 8*fNBytes;
  }
}

Get() [1/2]

void G4SurfBits::Get

(

char *

array

)

const

Optimized getters. Each of these will replace the contents of the parameter array with the bits in the receiver. The parameter array must be large enough to hold all of the bits in the receiver. Note on semantics: any bits in the parameter array that go beyond the number of the bits in the receiver will have an unspecified value. For example, if calling Get(Int*) with an array of one integer and the G4SurfBits object has less than 32 bits, then the remaining bits in the integer will have an unspecified value.

Definition at line 187 of file G4SurfBits.cc.

{
  // Copy all the bytes.
  std::memcpy(array, fAllBits, (fNBits+7)>>3);
}

Referenced by Get().

Get() [2/2]

void G4SurfBits::Get

(

G4int *

array

)

const

Definition at line 205 of file G4SurfBits.cc.

{
  // Get all the bytes.
 
  Get((char*)array);
}

GetNbits()

unsigned int G4SurfBits::GetNbits ( ) const

inline

Accessors.

Definition at line 121 of file G4SurfBits.hh.

{ return fNBits; }

GetNbytes()

unsigned int G4SurfBits::GetNbytes ( ) const

inline

Definition at line 122 of file G4SurfBits.hh.

{ return fNBytes; }

operator=()

G4SurfBits & G4SurfBits::operator=

(

const G4SurfBits &

rhs

)

Definition at line 57 of file G4SurfBits.cc.

{
  // G4SurfBits assignment operator
  if (this != &rhs)
  {
    //      TObject::operator=(rhs);
    fNBits   = rhs.fNBits;
    fNBytes  = rhs.fNBytes;
    delete [] fAllBits;
    if (fNBytes != 0)
    {
      fAllBits = new unsigned char[fNBytes];
      std::memcpy(fAllBits,rhs.fAllBits,fNBytes);
    }
    else
    {
      fAllBits = nullptr;
    }
  }
  return *this;
}

operator[]()

G4bool G4SurfBits::operator[] ( unsigned int bitnumber ) const

inline

Accessor operator.

Output()

void G4SurfBits::Output

(

std::ostream &

os

)

const

Definition at line 122 of file G4SurfBits.cc.

{
  // Print the value to the std::ostream
  for(unsigned int i=0; i<fNBytes; ++i)
  {
    unsigned char val = fAllBits[fNBytes - 1 - i];
    for (unsigned int j=0; j<8; ++j)
    {
      os << (G4bool)(val&0x80);
      val <<= 1;
    }
  }
}

Print()

void G4SurfBits::Print

(

)

const

Logging functions.

Definition at line 137 of file G4SurfBits.cc.

{
  // Print the list of active bits
  G4int count = 0;
  for(unsigned int i=0; i<fNBytes; ++i)
  {
    unsigned char val = fAllBits[i];
    for (unsigned int j=0; j<8; ++j)
    {
      if ((val & 1) != 0) { G4cout << " bit:" << count << " = 1" << G4endl; }
      ++count;
      val = val >> 1;
    }
  }
}

ResetAllBits()

void G4SurfBits::ResetAllBits

(

G4bool

value = false

)

Methods for bit manipulation.

Definition at line 154 of file G4SurfBits.cc.

{
  if (fAllBits != nullptr) { std::memset(fAllBits, value ? 0xFF : 0, fNBytes); }
}

ResetBitNumber()

void G4SurfBits::ResetBitNumber ( unsigned int bitnumber )

inline

Referenced by G4MultiUnion::DistanceToOutVoxels().

set() [1/2]

void G4SurfBits::set	(	unsigned int	nbits,
		const char *	array )

Optimized setters. Each of these will replace the contents of the receiver with the bitvector in the parameter array. The number of bits is changed to 'nbits'. If nbits is smaller than fNBits, the receiver will NOT be compacted.

Definition at line 175 of file G4SurfBits.cc.

{
  // set all the bytes
  unsigned int nbytes=(nBits+7)>>3;
 
  ReserveBytes(nbytes);
 
  fNBits=nBits;
  std::memcpy(fAllBits, array, nbytes);
}

Referenced by G4Voxelizer::DisplayListNodes(), and set().

set() [2/2]

void G4SurfBits::set	(	unsigned int	nbits,
		const G4int *	array )

Definition at line 197 of file G4SurfBits.cc.

{
  // set all the bytes.
 
  set(nBits, (const char*)array);
}

SetBitNumber()

void G4SurfBits::SetBitNumber ( unsigned int bitnumber, G4bool value = true )

inline

Referenced by G4MultiUnion::DistanceToOutVoxels().

TestBitNumber()

G4bool G4SurfBits::TestBitNumber ( unsigned int bitnumber ) const

inline

Member Data Documentation

fAllBits

unsigned char* G4SurfBits::fAllBits = nullptr

Definition at line 132 of file G4SurfBits.hh.

Referenced by Clear(), Compact(), G4SurfBits(), G4SurfBits(), Get(), G4Voxelizer::GetCandidatesVoxelArray(), G4Voxelizer::GetCandidatesVoxelArray(), operator=(), Output(), Print(), ResetAllBits(), set(), and ~G4SurfBits().

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The documentation for this class was generated from the following files:

• G4SurfBits.hh
• G4SurfBits.cc