如何得到9x,NT,2000下显卡显存？

Question

如题

Answer 1

#include <ddraw.h>#pragma comment(lib, "guids.lib") LPDIRECTDRAW2 lpdd;
HRESULT ddrval; ddrval = CoCreateInstance(CLSID_DirectDraw,
    NULL, CLSCTX_ALL, IID_IDirectDraw2, (void**)&lpdd);
if(!FAILED(ddrval))
{
ddrval = IDirectDraw2_Initialize(lpdd, NULL);
} DDCAPS ddcaps; ddcaps.dwSize = sizeof DDCAPS;
lpdd->GetCaps(&ddcaps, NULL); lpdd->Release(); DWORD dwMem = ddcaps.dwVidMemTotal; CoUninitialize();

Answer 2

谢谢！
不过为什么得到是32397824转为M是30.89M，而不是32M？

Answer 3

还有，显卡DAC的类型怎么得到？

Answer 4

The IDirectDraw2::GetCaps method fills in the capabilities of the device driver for the hardware and the hardware-emulation layer (HEL).HRESULT GetCaps(
  LPDDCAPS lpDDDriverCaps,  
  LPDDCAPS lpDDHELCaps  
);
 
Parameters
lpDDDriverCaps 
Address of a DDCAPS structure that will be filled with the capabilities of the hardware, as reported by the device driver. Set this parameter to NULL if device driver capabilities are not to be retrieved. 
lpDDHELCaps 
Address of a DDCAPS structure that will be filled with the capabilities of the HEL. Set this parameter to NULL if HEL capabilities are not to be retrieved.

Answer 5

如果你的硬件支持的话可以调用
lpdd->GetCaps(NULL,&ddcaps);来获取，第一种方式得到的会有误差以下是DDCAPS的定义，找你感兴趣的信息typedef struct _DDCAPS { 
    DWORD    dwSize; 
    DWORD    dwCaps;                  // driver-specific caps
    DWORD    dwCaps2;                 // more driver-specific caps
    DWORD    dwCKeyCaps;              // color key caps
    DWORD    dwFXCaps;                // stretching and effects caps
    DWORD    dwFXAlphaCaps;           // alpha caps
    DWORD    dwPalCaps;               // palette caps
    DWORD    dwSVCaps;                // stereo vision caps
    DWORD    dwAlphaBltConstBitDepths;       // alpha bit-depth members
    DWORD    dwAlphaBltPixelBitDepths;       //  .
    DWORD    dwAlphaBltSurfaceBitDepths;     //  .
    DWORD    dwAlphaOverlayConstBitDepths;   //  .
    DWORD    dwAlphaOverlayPixelBitDepths;   //  .
    DWORD    dwAlphaOverlaySurfaceBitDepths; //  .
    DWORD    dwZBufferBitDepths;      // Z-buffer bit depth
    DWORD    dwVidMemTotal;           // total video memory
    DWORD    dwVidMemFree;            // total free video memory
    DWORD    dwMaxVisibleOverlays;    // maximum visible overlays
    DWORD    dwCurrVisibleOverlays;   // overlays currently visible
    DWORD    dwNumFourCCCodes;        // number of supported FOURCC codes
    DWORD    dwAlignBoundarySrc;      // overlay alignment restrictions
    DWORD    dwAlignSizeSrc;          //  .
    DWORD    dwAlignBoundaryDest;     //  .
    DWORD    dwAlignSizeDest;         //  .
    DWORD    dwAlignStrideAlign;      // stride alignment
    DWORD    dwRops[DD_ROP_SPACE];    // supported raster ops
    DDSCAPS  ddsCaps;                 // general surface caps
    DWORD    dwMinOverlayStretch;     // overlay stretch factors
    DWORD    dwMaxOverlayStretch;     //  .
    DWORD    dwMinLiveVideoStretch;   // obsolete
    DWORD    dwMaxLiveVideoStretch;   //  .
    DWORD    dwMinHwCodecStretch;     //  .
    DWORD    dwMaxHwCodecStretch;     //  .
    DWORD    dwReserved1;             // reserved
    DWORD    dwReserved2;             //  .
    DWORD    dwReserved3;             //  .
    DWORD    dwSVBCaps;               // system-to-video blit related caps
    DWORD    dwSVBCKeyCaps;           //  .
    DWORD    dwSVBFXCaps;             //  .
    DWORD    dwSVBRops[DD_ROP_SPACE]; //  .
    DWORD    dwVSBCaps;               // video-to-system blit related caps
    DWORD    dwVSBCKeyCaps;           //  .
    DWORD    dwVSBFXCaps;             //  .
    DWORD    dwVSBRops[DD_ROP_SPACE]; //  .
    DWORD    dwSSBCaps;               // system-to-system blit related caps
    DWORD    dwSSBCKeyCaps;           //  .
    DWORD    dwSSBCFXCaps;            //  .
    DWORD    dwSSBRops[DD_ROP_SPACE]; //  .
    DWORD    dwMaxVideoPorts;         // maximum number of live video ports
    DWORD    dwCurrVideoPorts;        // current number of live video ports
    DWORD    dwSVBCaps2;              // additional system-to-video blit caps
    DWORD    dwNLVBCaps;              // nonlocal-to-local video memory blit caps
    DWORD    dwNLVBCaps2;             //  .
    DWORD    dwNLVBCKeyCaps;          //  .
    DWORD    dwNLVBFXCaps;            //  .
    DWORD    dwNLVBRops[DD_ROP_SPACE];//  .
    DWORD    dwReserved4;             // reserved
    DWORD    dwReserved5;             //  .
    DWORD    dwReserved6;             //  .
} DDCAPS,FAR* LPDDCAPS;