DWORD   dwRGBAlphaBitMask;      // mask for alpha channel
        DWORD   dwYUVAlphaBitMask;      // mask for alpha channel
        DWORD   dwLuminanceAlphaBitMask;// mask for alpha channel
        DWORD   dwRGBZBitMask;          // mask for Z channel
        DWORD   dwYUVZBitMask;          // mask for Z channel
    } DUMMYUNIONNAMEN(5);
} DDPIXELFORMAT;

typedef DDPIXELFORMAT FAR* LPDDPIXELFORMAT;

/*
 * DDOVERLAYFX
 */
typedef struct _DDOVERLAYFX
{
    DWORD       dwSize;                         // size of structure
    DWORD       dwAlphaEdgeBlendBitDepth;       // Bit depth used to specify constant for alpha edge blend
    DWORD       dwAlphaEdgeBlend;               // Constant to use as alpha for edge blend
    DWORD       dwReserved;
    DWORD       dwAlphaDestConstBitDepth;       // Bit depth used to specify alpha constant for destination
    union
    {
        DWORD   dwAlphaDestConst;               // Constant to use as alpha channel for dest
        LPDIRECTDRAWSURFACE lpDDSAlphaDest;     // Surface to use as alpha channel for dest
    } DUMMYUNIONNAMEN(1);
    DWORD       dwAlphaSrcConstBitDepth;        // Bit depth used to specify alpha constant for source
    union
    {
        DWORD   dwAlphaSrcConst;                // Constant to use as alpha channel for src
        LPDIRECTDRAWSURFACE lpDDSAlphaSrc;      // Surface to use as alpha channel for src
    } DUMMYUNIONNAMEN(2);
    DDCOLORKEY  dckDestColorkey;                // DestColorkey override
    DDCOLORKEY  dckSrcColorkey;                 // DestColorkey override
    DWORD       dwDDFX;                         // Overlay FX
    DWORD       dwFlags;                        // flags
} DDOVERLAYFX;

typedef DDOVERLAYFX FAR *LPDDOVERLAYFX;


/*
 * DDBLTBATCH: BltBatch entry structure
 */
typedef struct _DDBLTBATCH
{
    LPRECT              lprDest;
    LPDIRECTDRAWSURFACE lpDDSSrc;
    LPRECT              lprSrc;
    DWORD               dwFlags;
    LPDDBLTFX           lpDDBltFx;
} DDBLTBATCH;

typedef DDBLTBATCH FAR * LPDDBLTBATCH;


/*
 * DDGAMMARAMP
 */
typedef struct _DDGAMMARAMP
{
    WORD                red[256];
    WORD                green[256];
    WORD                blue[256];
} DDGAMMARAMP;
typedef DDGAMMARAMP FAR * LPDDGAMMARAMP;

/*
 *  This is the structure within which DirectDraw returns data about the current graphics driver and chipset
 */

#define MAX_DDDEVICEID_STRING           512

typedef struct tagDDDEVICEIDENTIFIER
{
    /*
     * These elements are for presentation to the user only. They should not be used to identify particular
     * drivers, since this is unreliable and many different strings may be associated with the same
     * device, and the same driver from different vendors.
     */
    char    szDriver[MAX_DDDEVICEID_STRING];
    char    szDescription[MAX_DDDEVICEID_STRING];

    /*
     * This element is the version of the DirectDraw/3D driver. It is legal to do <, > comparisons
     * on the whole 64 bits. Caution should be exercised if you use this element to identify problematic
     * drivers. It is recommended that guidDeviceIdentifier is used for this purpose.
     *
     * This version has the form:
     *  wProduct = HIWORD(liDriverVersion.HighPart)
     *  wVersion = LOWORD(liDriverVersion.HighPart)
     *  wSubVersion = HIWORD(liDriverVersion.LowPart)
     *  wBuild = LOWORD(liDriverVersion.LowPart)
     */
#ifdef _WIN32
    LARGE_INTEGER liDriverVersion;      /* Defined for applications and other 32 bit components */
#else
    DWORD   dwDriverVersionLowPart;     /* Defined for 16 bit driver components */
    DWORD   dwDriverVersionHighPart;
#endif


    /*
     * These elements can be used to identify particular chipsets. Use with extreme caution.
     *   dwVendorId     Identifies the manufacturer. May be zero if unknown.
     *   dwDeviceId     Identifies the type of chipset. May be zero if unknown.
     *   dwSubSysId     Identifies the subsystem, typically this means the particular board. May be zero if unknown.
     *   dwRevision     Identifies the revision level of the chipset. May be zero if unknown.
     */
    DWORD   dwVendorId;
    DWORD   dwDeviceId;
    DWORD   dwSubSysId;
    DWORD   dwRevision;

    /*
     * This element can be used to check changes in driver/chipset. This GUID is a unique identifier for the
     * driver/chipset pair. Use this element if you wish to track changes to the driver/chipset in order to
     * reprofile the graphics subsystem.
     * This element can also be used to identify particular problematic drivers.
     */
    GUID    guidDeviceIdentifier;
} DDDEVICEIDENTIFIER, * LPDDDEVICEIDENTIFIER;

typedef struct tagDDDEVICEIDENTIFIER2
{
    /*
     * These elements are for presentation to the user only. They should not be used to identify particular
     * drivers, since this is unreliable and many different strings may be associated with the same
     * device, and the same driver from different vendors.
     */
    char    szDriver[MAX_DDDEVICEID_STRING];
    char    szDescription[MAX_DDDEVICEID_STRING];

    /*
     * This element is the version of the DirectDraw/3D driver. It is legal to do <, > comparisons
     * on the whole 64 bits. Caution should be exercised if you use this element to identify problematic
     * drivers. It is recommended that guidDeviceIdentifier is used for this purpose.
     *
     * This version has the form:
     *  wProduct = HIWORD(liDriverVersion.HighPart)
     *  wVersion = LOWORD(liDriverVersion.HighPart)
     *  wSubVersion = HIWORD(liDriverVersion.LowPart)
     *  wBuild = LOWORD(liDriverVersion.LowPart)
     */
#ifdef _WIN32
    LARGE_INTEGER liDriverVersion;      /* Defined for applications and other 32 bit components */
#else
    DWORD   dwDriverVersionLowPart;     /* Defined for 16 bit driver components */
    DWORD   dwDriverVersionHighPart;
#endif


    /*
     * These elements can be used to identify particular chipsets. Use with extreme caution.
     *   dwVendorId     Identifies the manufacturer. May be zero if unknown.
     *   dwDeviceId     Identifies the type of chipset. May be zero if unknown.
     *   dwSubSysId     Identifies the subsystem, typically this means the particular board. May be zero if unknown.
     *   dwRevision     Identifies the revision level of the chipset. May be zero if unknown.
     */
    DWORD   dwVendorId;
    DWORD   dwDeviceId;
    DWORD   dwSubSysId;
    DWORD   dwRevision;

    /*
     * This element can be used to check changes in driver/chipset. This GUID is a unique identifier for the
     * driver/chipset pair. Use this element if you wish to track changes to the driver/chipset in order to
     * reprofile the graphics subsystem.
     * This element can also be used to identify particular problematic drivers.
     */
    GUID    guidDeviceIdentifier;

    /*
     * This element is used to determine the Windows Hardware Quality Lab (WHQL)
     * certification level for this driver/device pair.
     */
    DWORD   dwWHQLLevel;

} DDDEVICEIDENTIFIER2, * LPDDDEVICEIDENTIFIER2;

/*
 * Flags for the IDirectDraw4::GetDeviceIdentifier method
 */

/*
 * This flag causes GetDeviceIdentifier to return information about the host (typically 2D) adapter in a system equipped
 * with a stacked secondary 3D adapter. Such an adapter appears to the application as if it were part of the
 * host adapter, but is typically physcially located on a separate card. The stacked secondary's information is
 * returned when GetDeviceIdentifier's dwFlags field is zero, since this most accurately reflects the qualities
 * of the DirectDraw object involved.
 */
#define DDGDI_GETHOSTIDENTIFIER         0x00000001L

/*
 * Macros for interpretting DDEVICEIDENTIFIER2.dwWHQLLevel
 */
#define GET_WHQL_YEAR( dwWHQLLevel ) \
    ( (dwWHQLLevel) / 0x10000 )
#define GET_WHQL_MONTH( dwWHQLLevel ) \
    ( ( (dwWHQLLevel) / 0x100 ) & 0x00ff )
#define GET_WHQL_DAY( dwWHQLLevel ) \
    ( (dwWHQLLevel) & 0xff )


/*
 * callbacks
 */
typedef DWORD   (FAR PASCAL *LPCLIPPERCALLBACK)(LPDIRECTDRAWCLIPPER lpDDClipper, HWND hWnd, DWORD code, LPVOID lpContext );
#ifdef STREAMING
typedef DWORD   (FAR PASCAL *LPSURFACESTREAMINGCALLBACK)(DWORD);
#endif


/*
 * INTERACES FOLLOW:
 *      IDirectDraw
 *      IDirectDrawClipper
 *      IDirectDrawPalette
 *      IDirectDrawSurface
 */

/*
 * IDirectDraw
 */
#if defined( _WIN32 ) && !defined( _NO_COM )
#undef INTERFACE
#define INTERFACE IDirectDraw
DECLARE_INTERFACE_( IDirectDraw, IUnknown )
{
    /*** IUnknown methods ***/
    STDMETHOD(QueryInterface) (THIS_ REFIID riid, LPVOID FAR * ppvObj) PURE;
    STDMETHOD_(ULONG,AddRef) (THIS)  PURE;
    STDMETHOD_(ULONG,Release) (THIS) PURE;
    /*** IDirectDraw methods ***/
    STDMETHOD(Compact)(THIS) PURE;
    STDMETHOD(CreateClipper)(THIS_ DWORD, LPDIRECTDRAWCLIPPER FAR*, IUnknown FAR * ) PURE;
    STDMETHOD(CreatePalette)(THIS_ DWORD, LPPALETTEENTRY, LPDIRECTDRAWPALETTE FAR*, IUnknown FAR * ) PURE;
    STDMETHOD(CreateSurface)(THIS_  LPDDSURFACEDESC, LPDIRECTDRAWSURFACE FAR *, IUnknown FAR *) PURE;
    STDMETHOD(DuplicateSurface)( THIS_ LPDIRECTDRAWSURFACE, LPDIRECTDRAWSURFACE FAR * ) PURE;
    STDMETHOD(EnumDisplayModes)( THIS_ DWORD, LPDDSURFACEDESC, LPVOID, LPDDENUMMODESCALLBACK ) PURE;
    STDMETHOD(EnumSurfaces)(THIS_ DWORD, LPDDSURFACEDESC, LPVOID,LPDDENUMSURFACESCALLBACK ) PURE;
    STDMETHOD(FlipToGDISurface)(THIS) PURE;