VC实现自绘图形输出到bmp文件

实现方法

要把文本和图形保存到位图文件，只要对掌握位图结构有一定的了解，一切都ok呢。先必须要创建内存设备环境，然后内存设备环境创建的DIB区域，别忘 了还要创建个CBitmap对象，CBitmap对象必须和DIB区域关联起来，把CBitmap对象选择到当前设备环境，然后在当前设备环境输出文本和 图形就可以了。

具体实现代码如下

  
    

   
     
void CTestSaveBmpView::SaveAsBmp(CString filename)

{

	//定义图形大小

	int iWidth = 800;

	int iHeight = 600;

	int iPixel = 16;

	//图形格式参数

	LPBITMAPINFO lpbmih = new BITMAPINFO;

	lpbmih->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);

	lpbmih->bmiHeader.biWidth = iWidth;

	lpbmih->bmiHeader.biHeight = iHeight;

	lpbmih->bmiHeader.biPlanes = 1;

	lpbmih->bmiHeader.biBitCount = iPixel;

	lpbmih->bmiHeader.biCompression = BI_RGB;

	lpbmih->bmiHeader.biSizeImage = 0;

	lpbmih->bmiHeader.biXPelsPerMeter = 0;

	lpbmih->bmiHeader.biYPelsPerMeter = 0;

	lpbmih->bmiHeader.biClrUsed = 0;

	lpbmih->bmiHeader.biClrImportant = 0;

	

	//创建位图数据

	HDC hdc,hdcMem;

	HBITMAP hBitMap = NULL;

	CBitmap *pBitMap = NULL;

	CDC *pMemDC = NULL;

	BYTE *pBits;

	

	hdc = CreateIC(TEXT("DISPLAY"),NULL,NULL,NULL);

	hdcMem = CreateCompatibleDC(hdc);

	hBitMap = CreateDIBSection(hdcMem,lpbmih,DIB_PAL_COLORS,(void **)&pBits,NULL,0);

	pBitMap = new CBitmap;

	pBitMap->Attach(hBitMap);

	pMemDC = new CDC;

	pMemDC->Attach(hdcMem);

	pMemDC->SelectObject(pBitMap);

	//

	CRect rc(0,0,iWidth,iHeight);

	pMemDC->SetBkMode(TRANSPARENT);

	//添加自绘图形 

	DrawCurve(pMemDC,rc);

	//保存到文件并创建位图结构

	BITMAPFILEHEADER bmfh;

	ZeroMemory(&bmfh,sizeof(BITMAPFILEHEADER));

	*((char *)&bmfh.bfType) = ''B'';

	*(((char *)&bmfh.bfType) + 1) = ''M'';

	bmfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);

	bmfh.bfSize = bmfh.bfOffBits + (iWidth * iHeight) * iPixel / 8;

	

	TCHAR szBMPFileName[128];

	int iBMPBytes = iWidth * iHeight * iPixel / 8;

	strcpy(szBMPFileName,filename);

	CFile file;

	if(file.Open(szBMPFileName,CFile::modeWrite | CFile::modeCreate))

	{

		file.Write(&bmfh,sizeof(BITMAPFILEHEADER));

		file.Write(&(lpbmih->bmiHeader),sizeof(BITMAPINFOHEADER));

		file.Write(pBits,iBMPBytes);

		file.Close();

	}

	

	pMemDC->DeleteDC();

	delete pMemDC; pMemDC = NULL;

	delete pBitMap; pBitMap = NULL;

	delete lpbmih; lpbmih = NULL;

}



//输出文本和图形



void CTestSaveBmpView::DrawCurve(CDC *pDC, CRect rcClient)

{

	//页面背景色

	CBrush brushCtl;

	brushCtl.CreateSolidBrush(RGB(255,255,255));

	pDC->Rectangle(rcClient);

	pDC->FillRect(rcClient,&brushCtl) ;

	brushCtl.DeleteObject();

	

	CPen pen;

	pen.CreatePen(PS_SOLID, 1, RGB(255,0,0));

	CPen *oldPen = pDC->SelectObject(&pen); 

	

	double xMin = 10.00f, xMax = 100.00f;

	double yMin = 10.00f, yMax = 200.00f;

	

	double dbX1 = (xMax- xMin)/100 + xMin;

	double dbY1 = 600/dbX1 ;

	for (int i=1; i<100; i++) //曲线

	{

		double dbX2 = (xMax- xMin)*i/100 + xMin;

		double dbY2 = 600/dbX2 ;

		

		pDC->MoveTo(int(rcClient.left+(dbX1 - xMin)*rcClient.Width()/(xMax- xMin)), 

			int(rcClient.bottom-(dbY1- yMin)*rcClient.Height()/(yMax- yMin)));

		pDC->LineTo(int(rcClient.left+(dbX2 - xMin)*rcClient.Width()/(xMax- xMin)), 

			int(rcClient.bottom-(dbY2- yMin)*rcClient.Height()/(yMax- yMin))); 

		

		dbX1=dbX2;

		dbY1=dbY2;

	}

	pDC->SelectObject(oldPen); 

	pen.DeleteObject();

	oldPen = NULL;

}



//保存的实现

void CTestSaveBmpView::OnRButtonDown(UINT nFlags, CPoint point) 

{

	

	CFileDialog dlg(false,NULL,NULL,OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,

		"位图文件(*.bmp)|*.bmp|",

		NULL);

	if (dlg.DoModal()!= IDOK) return;

	CString filename = dlg.GetFileName() + ".bmp";

	SaveAsBmp(filename); 

	

	CView::OnRButtonDown(nFlags, point);

}