dib.cpp

Viaual C++实战演练一书的源代码,对于C++程序员有实际的借鉴意义．

#include "stdafx.h"
#include "Dib.h"

/*
*
*	Parameters:
*	
*	DWORD dwWidth    - Width for new bitmap, in pixels
*
*	DWORD dwHeight   - Height for New bitmap
*
*	WORD  wBitCount  - Bit Count for new DIB (1, 4, 8, 24)
*
*	Return Value:
*
*	HDIB             - Handle to new DIB
*
*/

HDIB CDib::CreateDIB(DWORD dwWidth, DWORD dwHeight, WORD wBitCount)
{
	BITMAPINFOHEADER	bi;
	LPBITMAPINFOHEADER	lpbi;
	DWORD				dwLen;
	HDIB				hDib;
	DWORD				dwBytesPerLine;

	if(wBitCount <=1)
		wBitCount = 1;
	else if(wBitCount <=4)
		wBitCount = 4;
	else if(wBitCount <=8)
		wBitCount = 8;
	else if(wBitCount <=24)
		wBitCount = 24;
	else
		wBitCount = 4;

	bi.biSize=sizeof(BITMAPINFOHEADER);
	bi.biWidth = dwWidth;
	bi.biHeight=dwHeight;
	bi.biPlanes=1;
	bi.biBitCount=wBitCount;
	bi.biCompression=BI_RGB;
	bi.biSizeImage=0;
	bi.biXPelsPerMeter=0;
	bi.biYPelsPerMeter=0;
	bi.biClrUsed=0;
	bi.biClrImportant=0;

	dwBytesPerLine=WIDTHBYTES(wBitCount * dwWidth);
	dwLen=bi.biSize+PaletteSize((LPBYTE)&bi) +
		(dwBytesPerLine * dwHeight);
	hDib = GlobalAlloc(GHND, dwLen);

	if(!hDib)
		return NULL;

	lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);
	*lpbi = bi;

	GlobalUnlock(hDib);

	return hDib;
}