C++博客-《深入解析ATL》第二版中文版上市-随笔分类-Graphics

C++博客-《深入解析ATL》第二版中文版上市-随笔分类-Graphicshttp://www.cppblog.com/TechLab/category/170.html有问题请到CSDN->VC/MFC讨论zh-cnTue, 20 May 2008 15:08:17 GMTTue, 20 May 2008 15:08:17 GMT60GDI转BMP为WMFhttp://www.cppblog.com/TechLab/archive/2006/01/12/2640.htmlTechLabTechLabThu, 12 Jan 2006 02:25:00 GMThttp://www.cppblog.com/TechLab/archive/2006/01/12/2640.htmlhttp://www.cppblog.com/TechLab/comments/2640.htmlhttp://www.cppblog.com/TechLab/archive/2006/01/12/2640.html#Feedback3http://www.cppblog.com/TechLab/comments/commentRss/2640.htmlhttp://www.cppblog.com/TechLab/services/trackbacks/2640.htmlHDC hdc = CreateMetaFile("c:\\test.wmf"); //测试的目标文件路径
HBITMAP hbmp = (HBITMAP)::LoadImage(NULL,"c:\\te12.bmp",IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
CDC memdc;
memdc.CreateCompatibleDC(GetDC());
HBITMAP hold = (HBITMAP)memdc.SelectObject(hbmp);
BITMAP bmp;
::GetObject(hbmp,sizeof(bmp),&bmp);
if(hbmp != NULL)
{
BitBlt(hdc,0,0,bmp.bmWidth,bmp.bmHeight,memdc.m_hDC,0,0,SRCCOPY);
}
memdc.SelectObject(hold);
memdc.DeleteDC();
CloseMetaFile(hdc);

TechLab 2006-01-12 10:25 发表评论

]]>利用IPicture接口加载、显示图片http://www.cppblog.com/TechLab/archive/2005/10/20/758.htmlTechLabTechLabThu, 20 Oct 2005 06:50:00 GMThttp://www.cppblog.com/TechLab/archive/2005/10/20/758.htmlhttp://www.cppblog.com/TechLab/comments/758.htmlhttp://www.cppblog.com/TechLab/archive/2005/10/20/758.html#Feedback1http://www.cppblog.com/TechLab/comments/commentRss/758.htmlhttp://www.cppblog.com/TechLab/services/trackbacks/758.htmlIPicture接口管理一个图片对象和它的属性。图片对象提供对Bitmap Icon Metafile的语言不相关的抽象支持。图像对象的主要接口是IPicture和IPictureDisp。IPictureDisp从IDispatch继承，提供了通过自动化访问图片属性的能力。图片对象可通过OleCreatePictureIndirect创建。关于IPicture支持的其他接口和方法可以看MSDN，一般创建图片对象可以用OleLoadPicture函数，它简化了基于流内容创建图片对象。下面的代码中有两个未定义的变量是FilePath和hDC。
//FilePath是从外部传入的图片路径
//打开文件
HANDLE hFile = CreateFile(FilePath, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
_ASSERTE(INVALID_HANDLE_VALUE != hFile);
//取文件大小
DWORD dwFileSize = GetFileSize(hFile, NULL);
_ASSERTE(-1 != dwFileSize);
LPVOID pvData = NULL;
//分配内存，准备读入图片文件的数据
//GlobalAlloc从堆分配指定字节的内存区域
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
_ASSERTE(NULL != hGlobal);
//GlobalLock函数锁住一个全局的内存对象同时返回一个指向对象首字节的指针
pvData = GlobalLock(hGlobal);
_ASSERTE(NULL != pvData);
DWORD dwBytesRead = 0;
//读取文件的数据到分配的全局内存
BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
_ASSERTE(FALSE != bRead);
GlobalUnlock(hGlobal);
CloseHandle(hFile);

//到此，我们已经把文件的数据读到了内存当中

LPSTREAM pstm = NULL;
//从全局内存创建IStream接口指针
HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
_ASSERTE(SUCCEEDED(hr) && pstm);
//根据图片文件创建IPicture接口指针
hr = ::OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
_ASSERTE(SUCCEEDED(hr) && gpPicture);
pstm->Release();

//至此，IPicture接口建立好，下面开始画图片
//hDC是外部传入的画图设备
long hmWidth;
long hmHeight;
gpPicture->get_Width(&hmWidth);
gpPicture->get_Height(&hmHeight);
//转换himetric距离为pixels距离，1英寸=25.4毫米
int nWidth = MulDiv(hmWidth, GetDeviceCaps(hDC, LOGPIXELSX), 2540);
int nHeight = MulDiv(hmHeight, GetDeviceCaps(hDC, LOGPIXELSY), 2540);
RECT rc;
GetClientRect(hWnd, &rc);
//IPicture::Render显示图片
gpPicture->Render(hDC, 0, 0, nWidth, nHeight, 0, hmHeight, hmWidth, -hmHeight, &rc);

TechLab 2005-10-20 14:50 发表评论

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