// Dib.cpp: implementation of the CDib class.
//
//////////////////////////////////////////////////////////////////////
#include "StdAfx.h"
#include "Dib.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
CDib::CDib()
{
m_hDrawDib=NULL;
m_pDib=NULL;
}
CDib::~CDib()
{
Close();
}
void CDib::Draw(CDC *pDC,int nWidth, int nHeight)
{
if(m_pDib!=NULL)
{
ASSERT(IsValid());
DrawDibRealize(m_hDrawDib,pDC->GetSafeHdc(),TRUE);
DrawDibDraw(m_hDrawDib,pDC->GetSafeHdc(),
0, //desktop left
0, //desktop top
nWidth,
nHeight,
(BITMAPINFOHEADER *)m_pDib,
(LPVOID) GetBits(),
0, //source left
0, //source top
((BITMAPINFOHEADER *)m_pDib)->biWidth,
((BITMAPINFOHEADER *)m_pDib)->biHeight,
DDF_BACKGROUNDPAL);
}
}
CSize CDib::GetSize()
{
return CSize(((BITMAPINFOHEADER *)m_pDib)->biWidth,
((BITMAPINFOHEADER *)m_pDib)->biHeight);
}
LONG CDib::GetWidth()
{
return ((BITMAPINFOHEADER *)m_pDib)->biWidth;
}
LONG CDib::GetHeight()
{
return ((BITMAPINFOHEADER *)m_pDib)->biHeight;
}
void CDib::Close()
{
if(m_hDrawDib!=NULL)
{
DrawDibClose(m_hDrawDib);
m_hDrawDib=NULL;
}
if(m_pDib!=NULL)
{
delete m_pDib;
m_pDib=NULL;
}
}
BOOL CDib::Open(const char * pzFileName)
{
// BITMAPFILEHEADER bmpFileHeader;
CFile file;
int nBmpFileHeaderSize;
Close();
//drawdibopen initialize the diradib library and
//returns a handle for all drawdib operations
if(!(m_hDrawDib=DrawDibOpen()))
goto exit;
//open and read the DIB file header
nBmpFileHeaderSize=sizeof(BITMAPFILEHEADER);
if(!file.Open(pzFileName,CFile::modeRead | CFile::typeBinary))
goto exit;
if(file.Read((void *)&bmpFileHeader,nBmpFileHeaderSize)!=(UINT)nBmpFileHeaderSize)
goto failure;
//validate the DIB file header by checking the first
//two characters for the signature "BM"
if(bmpFileHeader.bfType!=*((WORD *)"BM"))
goto failure;
//allocate a big chuck of global memory to store the DIB
m_pDib=(BYTE *)new char [bmpFileHeader.bfSize-nBmpFileHeaderSize];
//allocate memory fail
if(!m_pDib)
goto failure;
//read the dib into the buffer at a time using ReadHuge
file.ReadHuge(m_pDib,bmpFileHeader.bfSize-nBmpFileHeaderSize);
if(((BITMAPINFOHEADER *)m_pDib)->biSizeImage==0)
{
//the application that create this bitmap didn't fill
//in the biSizeImage field. Let's fill it
//in even though the DrawDib * functions don't need it.
BITMAPINFOHEADER *pDib=(BITMAPINFOHEADER *)m_pDib;
//scan lines must be DWord aligned, hence the strange bit stuff
pDib->biSizeImage=((((pDib->biWidth*pDib->biBitCount)+31)&~31)>>3)*pDib->biHeight;
}
m_pDibBits=GetBits();
file.Close();
return TRUE;
failure:
file.Close();
exit:
Close();
return FALSE;
}
BOOL CDib::Save(const char * pzFileName)
{
// BITMAPFILEHEADER bmpFileHeader;
CFile file;
int nBmpFileHeaderSize;
//open and read the DIB file header
nBmpFileHeaderSize=sizeof(BITMAPFILEHEADER);
if(!file.Open(pzFileName,CFile::modeCreate | CFile::modeWrite | CFile::typeBinary))
goto exit;
file.Write(&bmpFileHeader,nBmpFileHeaderSize);
//allocate memory fail
if(!m_pDib)
goto failure;
//read the dib into the buffer at a time using ReadHuge
file.WriteHuge(m_pDib,bmpFileHeader.bfSize-nBmpFileHeaderSize);
file.Close();
return TRUE;
failure:
file.Close();
exit:
return FALSE;
}
BYTE * CDib::GetBits()
{
//the size of the color map is determined by the number
//of RGBQUAD structures presend.
//it also depends on the bit_depth of the Dib
DWORD dwNumColors,dwColorTableSize;
BITMAPINFOHEADER *lpDib=(BITMAPINFOHEADER *)m_pDib;
WORD wBitCount=lpDib->biBitCount;
if(lpDib->biSize>=36)
dwNumColors=lpDib->biClrUsed;
else
dwNumColors=0;
if(dwNumColors==0)
{
if(wBitCount!=24)
dwNumColors=1L<<wBitCount;
else
dwNumColors=0;
}
dwColorTableSize=dwNumColors*sizeof(RGBQUAD);
return m_pDib+lpDib->biSize+dwColorTableSize;
}
int CDib::GetBiBitCount()
{
if(m_pDib!=NULL)
return ((BITMAPINFOHEADER *)m_pDib)->biBitCount;
return 0;
}
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