请求高人指点VB关于Drectx 3D窗口后台截图
对3D游戏窗口进行截图PrintWindow截出黑屏，全用Bitblt只能截取显示在桌面前台的部分，怎样才能截取屏外或隐藏状态下的图片呢？在网上磨了一个月，没找到合适的方法，那位高人能指点一下？在些先谢谢了！（只有5分了，以前送分多，可是都没得到有效的回答，希望不要介意分太少。）
--------------------编程问答--------------------
//GDI与DX截屏API操作
LPDIRECTDRAW lpDD = NULL;
LPDIRECTDRAWSURFACE lpDDSPrime = NULL;
LPDIRECTDRAWSURFACE lpDDSBack = NULL;
LPDIRECTDRAWSURFACE lpDDSGdi = NULL;
LPDIRECTDRAWSURFACE lpSurf = NULL;
DDSURFACEDESC DDSdesc;
BOOL m_b24=TRUE;
//rfbServerInitMsg m_scrinfo;
RECT m_bmrect;
struct _BMInfo {
BITMAPINFO bmi ;
BOOL truecolour;
RGBQUAD cmap[256] ;
} m_bminfo; // 用来保存位图信息的结构
int DX_Init() {// DirectX初始化。返回当前表面获取一张屏幕位图的存储空间大小
HRESULT hr;
// 初始化directX
hr = DirectDrawCreate(0, &lpDD, 0);
if (FAILED(hr)) return FALSE;
hr = lpDD->SetCooperativeLevel(NULL, DDSCL_NORMAL);
if (FAILED(hr)) return FALSE;
ZeroMemory(&DDSdesc, sizeof(DDSdesc));
DDSdesc.dwSize = sizeof(DDSdesc);
DDSdesc.dwFlags = DDSD_CAPS;
DDSdesc.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE;
hr = lpDD->CreateSu易做图ce(&DDSdesc, &lpDDSPrime, 0);
if (FAILED(hr)) return FALSE;
hr = lpDD->GetGDISu易做图ce(&lpDDSGdi);
if (FAILED(hr)) return FALSE;
ZeroMemory(&DDSdesc, sizeof(DDSdesc));
DDSdesc.dwSize = sizeof(DDSdesc);
DDSdesc.dwFlags = DDSD_ALL;
hr = lpDDSPrime->GetSu易做图ceDesc(&DDSdesc);
if (FAILED(hr)) return FALSE;
// 初始化位图信息
if ((DDSdesc.dwFlags & DDSD_WIDTH) && (DDSdesc.dwFlags & DDSD_HEIGHT)) {
m_bmrect.left = m_bmrect.top = 0;
m_bmrect.right = DDSdesc.dwWidth;
m_bmrect.bottom = DDSdesc.dwHeight;
} else return FALSE;
m_bminfo.bmi.bmiHeader.biCompression = BI_RGB;//BI_BITFIELDS;
m_bminfo.bmi.bmiHeader.biBitCount = DDSdesc.ddpfPixelFormat.dwRGBBitCount;
// m_bminfo.truecolour = DDSdesc.ddpfPixelFormat.dwFlags & DDPF_RGB;
if (m_bminfo.bmi.bmiHeader.biBitCount > 8)
m_bminfo.truecolour = TRUE;
else
m_bminfo.truecolour = FALSE;
ZeroMemory(&DDSdesc, sizeof(DDSdesc));
DDSdesc.dwSize = sizeof(DDSdesc);
DDSdesc.dwFlags = DDSD_CAPS | DDSD_HEIGHT |DDSD_WIDTH;
DDSdesc.ddsCaps.dwCaps = DDSCAPS_OFFSCREENPLAIN;
DDSdesc.dwHeight = m_bmrect.bottom - m_bmrect.top;
DDSdesc.dwWidth = m_bmrect.right - m_bmrect.left;
hr = lpDD->CreateSu易做图ce(&DDSdesc, &lpDDSBack, 0);
if (FAILED(hr)) return FALSE;
// hr = lpDDSPrime->QueryInte易做图ce( IID_IDirectDrawSu易做图ce3, (LPVOID *)&lpSurf);
// if (FAILED(hr)) return FALSE;
switch (m_bminfo.bmi.bmiHeader.biBitCount) {
case 32:
case 24:
// Update the bitmapinfo header
m_b24 = TRUE;
m_bminfo.bmi.bmiHeader.biSize = sizeof( BITMAPINFOHEADER );
m_bminfo.bmi.bmiHeader.biWidth = 1024;
m_bminfo.bmi.bmiHeader.biHeight = 768;
m_bminfo.bmi.bmiHeader.biPlanes = 1;
// m_bminfo.bmi.bmiHeader.biBitCount = 24;
m_bminfo.bmi.bmiHeader.biCompression = BI_RGB;
m_bminfo.bmi.bmiHeader.biSizeImage = abs((m_bminfo.bmi.bmiHeader.biWidth * m_bminfo.bmi.bmiHeader.biHeight * m_bminfo.bmi.bmiHeader.biBitCount)/8);
m_bminfo.bmi.bmiHeader.biXPelsPerMeter = (1024*1000)/1024;
m_bminfo.bmi.bmiHeader.biYPelsPerMeter = (768*1000)/768;
m_bminfo.bmi.bmiHeader.biClrUsed = 0;
m_bminfo.bmi.bmiHeader.biClrImportant = 0;
break;
}
return m_bminfo.bmi.bmiHeader.biSizeImage;
}
BOOL CaptureScreen(RECT &rect, BYTE *scrBuff, UINT scrBuffSize) {// 捕捉屏幕。rect: 区域。scrBuff: 输出缓冲。scrBuffSize: 缓冲区大小
HRESULT hr=0;
hr = lpDDSBack->BltFast(rect.left,rect.top,lpDDSPrime,&rect,DDBLTFAST_NOCOLORKEY | DDBLTFAST_WAIT);
if (FAILED(hr)) return FALSE;
DDSURFACEDESC surfdesc;
ZeroMemory(&surfdesc, sizeof(surfdesc));
surfdesc.dwSize = sizeof(surfdesc);
hr = lpDDSBack->Lock(&rect, &surfdesc, DDLOCK_READONLY | DDLOCK_WAIT | DDLOCK_SURFACEMEMORYPTR /*|DDLOCK_NOSYSLOCK*/, NULL);
// hr = lpDDSPrime->Lock(&rect, &surfdesc, DDLOCK_READONLY | DDLOCK_WAIT | DDLOCK_SURFACEMEMORYPTR /*|DDLOCK_NOSYSLOCK*/, NULL);
if (FAILED(hr)) return FALSE;
// copy the data into our buffer
BYTE * destbuffpos, * srcbuffpos;
// m_scrinfo.format.bitsPerPixel = 24;
srcbuffpos = (BYTE *) surfdesc.lpSu易做图ce;
destbuffpos = scrBuff;
memcpy( destbuffpos, srcbuffpos,m_bminfo.bmi.bmiHeader.biSizeImage);
// unlock the primary su易做图ce
// lpDDSPrime->Unlock(surfdesc.lpSu易做图ce);
lpDDSBack->Unlock(surfdesc.lpSu易做图ce);
return TRUE;
}
int SaveBitmapToFile(BITMAP *bitmap, LPSTR lpFileName,char *lpBuf) {
DWORD dwWritten;
BITMAPFILEHEADER bmfHdr;
BITMAPINFOHEADER bi;
HANDLE fh=NULL;
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth= bitmap->bmWidth;
bi.biHeight = bitmap->bmHeight;
bi.biPlanes = 1;
bi.biBitCount = bitmap->bmBitsPixel*8;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;
fh = CreateFile(lpFileName, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL);
if (fh == INVALID_HANDLE_VALUE) return FALSE;
bmfHdr.bfType = 0x4D42; // "BM"
bmfHdr.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER)+bitmap->bmWidth*bitmap->bmHeight*bitmap->bmBitsPixel;
bmfHdr.bfReserved1 = 0;
bmfHdr.bfReserved2 = 0;
bmfHdr.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER) + (DWORD)sizeof(BITMAPINFOHEADER);
WriteFile(fh, (LPSTR)&bmfHdr, sizeof(BITMAPFILEHEADER), &dwWritten, NULL);
WriteFile(fh, (char *)&bi,sizeof(BITMAPINFOHEADER), &dwWritten, NULL);
WriteFile(fh, (char *)lpBuf,bitmap->bmWidth*bitmap->bmHeight*bitmap->bmBitsPixel, &dwWritten, NULL);
FlushFileBuffers(fh);
CloseHandle(fh);
return true;
}
//(1)获取屏幕绘图设备
//(2)创建一个与屏幕绘图设备相兼容的内存绘图设备
//(2)在内存中创建一个与屏幕绘图设备相兼容的图像对象
//(3)将屏幕设备中的图像复制到内存绘图设备中
//(4)将内存图像保存到文件中
//相关函数：
//GetDIBits:按位的方式返回指定的BITMAP，并按指定的格式存储到内存中
int GetBitmapFromScreen(char *lpFileName) {
char *lpBuf;
HBITMAP hBitmap,hOld ;
HDC hDC,hcDC;
BITMAP bb;
BITMAPINFO b;
HANDLE hp,fh=NULL;
DWORD dwX,dwY;
dwX=GetSystemMetrics(SM_CXSCREEN);
dwY=GetSystemMetrics(SM_CYSCREEN);
hDC=GetDC(NULL);
hcDC=CreateCompatibleDC(hDC);
hBitmap=CreateCompatibleBitmap(hDC,dwX,dwY);
hOld=(HBITMAP)SelectObject(hcDC,hBitmap);
BitBlt(hcDC,0, 0,dwX,dwY, hDC, 0, 0, SRCCOPY);
bb.bmWidth=dwX;
bb.bmHeight =dwY;
bb.bmPlanes = 1;
bb.bmWidthBytes=bb.bmWidth*3;
bb.bmBitsPixel=3;
bb.bmType=0;
b.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
b.bmiHeader.biWidth =dwX;
b.bmiHeader.biHeight =dwY;
b.bmiHeader.biPlanes =1;
b.bmiHeader.biBitCount =3*8;
b.bmiHeader.biCompression =BI_RGB;
b.bmiHeader.biSizeImage =0;
b.bmiHeader.biXPelsPerMeter=0;
b.bmiHeader.biYPelsPerMeter=0;
b.bmiHeader.biClrUsed =0;
b.bmiHeader.biClrImportant =0;
b.bmiColors[0].rgbBlue =8;
b.bmiColors[0].rgbGreen =8;
b.bmiColors[0].rgbRed =8;
b.bmiColors[0].rgbReserved =0;
hp=GetProcessHeap();
lpBuf=(char *)HeapAlloc(hp,HEAP_ZERO_MEMORY,bb.bmHeight*bb.bmWidth*4);
GetDIBits(hcDC,hBitmap,0,dwY,lpBuf,&b,DIB_RGB_COLORS);
SaveBitmapToFile(&bb,lpFileName,lpBuf);
ReleaseDC(NULL,hDC);
DeleteDC(hcDC);
DeleteObject(hBitmap);
DeleteObject(hOld);
HeapFree(hp,0,lpBuf);
return true;
}
补充：VB , 非技术类
