IDirectDrawSurface4::SetPrivateData

The IDirectDrawSurface4::SetPrivateData method associates data with the surface that is intended for use by the application, not by DirectDraw. Data is passed by value, and multiple sets of data can be associated with a single surface.

HRESULT SetPrivateData( 
  REFGUID guidTag, 
  LPVOID  lpData,
  DWORD   cbSize,
  DWORD   dwFlags 
); 
 

Parameters

guidTag

Reference to (C++) or address of (C) the globally unique identifier that identifies the private data to be set.

lpData

Address of a buffer that contains the data to be associated with the surface.

cbSize

Size of the buffer at lpData, in bytes.

dwFlags

Flags describing the type of data being passed, or requesting that the data be invalidated when the surface changes. The following flags are defined:

(none)

If no flags are specified, DirectDraw allocates memory to hold the data within the buffer, and copies the data into the new buffer. The buffer allocated by DirectDraw will automatically be freed as appropriate.

DDSPD_IUNKNOWNPOINTER

The data at lpData is a pointer to an IUnknown interface. DirectDraw automatically calls the IUnknown::AddRef method of this interface. When this data is no longer needed, DirectDraw automatically calls the IUnknown::Release method of this interface.

DDSPD_VOLATILE

The buffer at lpData is only valid while the surface remains unchanged from its current state. If the surface's contents change, subsequent calls to the IDirectDrawSurface4::GetPrivateData method will return DDERR_EXPIRED.

Return Values

If the method succeeds, the return value is DD_OK.

If the method fails, the return value may be one of the following error values:

Remarks

DirectDraw does not manage the memory at lpData. If this buffer was dynamically allocated, it is the caller's responsibility to free the memory.

QuickInfo

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in ddraw.h.
  Import Library: Use ddraw.lib.

See Also

IDirectDrawSurface4::GetPrivateData, IDirectDrawSurface4::FreePrivateData