www.pudn.com > QuadTreeLOD4cs.rar > Bit.cpp, change:2006-06-12,size:1164b

// Bit.cpp: implementation of the CBit class. 
// 
////////////////////////////////////////////////////////////////////// 
 
#include "Bit.h" 
#include <memory.h> 
////////////////////////////////////////////////////////////////////// 
// Construction/Destruction 
////////////////////////////////////////////////////////////////////// 
 
CBit::CBit() 
{ 
	m_pBits = 0; 
	m_nSclae = 1; 
} 
 
CBit::~CBit() 
{ 
	if(m_pBits) 
		delete []m_pBits; 
} 
// x±ØÐëÊÇ8µÄ±¶Êý 
bool CBit::Create(int nXBits,int nZRows) 
{ 
	m_nXBytes = nXBits/8+1; 
	m_nZRows = nZRows; 
//	if(m_nXBits%8!=0)return false; 
	m_pBits = new unsigned char[m_nXBytes*m_nZRows]; 
	memset(m_pBits,0,m_nXBytes*m_nZRows); 
	return true; 
} 
 
void CBit::Reset() 
{ 
	memset(m_pBits,0,m_nXBytes*m_nZRows); 
} 
bool CBit::IsTrue(int x,int y) 
{ 
	x = x/m_nSclae; 
	y = y/m_nSclae; 
	unsigned char c = m_pBits[m_nXBytes*y+x/8]; 
	c = c<<(x%8); 
	return c&0x80; 
} 
 
void CBit::Set(int x, int y,bool bFlag) 
{ 
	x = x/m_nSclae; 
	y = y/m_nSclae; 
	unsigned char &c = m_pBits[m_nXBytes*y+x/8]; 
	unsigned char d = 0x80; 
	d = d >>(x%8); 
	if(bFlag) 
	{ 
		c |=d; 
	} 
	else 
	{ 
		d =~d; 
		c &=d; 
	} 
}