IDXGIOutputDuplication::GetFrameMoveRects method (dxgi1_2.h)

Gets information about the moved rectangles for the current desktop frame.

Syntax

HRESULT GetFrameMoveRects(
  [in]  UINT                   MoveRectsBufferSize,
  [out] DXGI_OUTDUPL_MOVE_RECT *pMoveRectBuffer,
  [out] UINT                   *pMoveRectsBufferSizeRequired
);

Parameters

[in] MoveRectsBufferSize

The size in bytes of the buffer that the caller passed to the pMoveRectBuffer parameter.

[out] pMoveRectBuffer

A pointer to an array of DXGI_OUTDUPL_MOVE_RECT structures that identifies the moved rectangle regions for the desktop frame.

[out] pMoveRectsBufferSizeRequired

Pointer to a variable that receives the number of bytes that GetFrameMoveRects needs to store information about moved regions in the buffer at pMoveRectBuffer.

For more information about returning the required buffer size, see Remarks.

Return value

GetFrameMoveRects returns:

  • S_OK if it successfully retrieved information about moved rectangles.
  • DXGI_ERROR_ACCESS_LOST if the desktop duplication interface is invalid. The desktop duplication interface typically becomes invalid when a different type of image is displayed on the desktop. Examples of this situation are:
    • Desktop switch
    • Mode change
    • Switch from DWM on, DWM off, or other full-screen application
    In this situation, the application must release the IDXGIOutputDuplication interface and create a new IDXGIOutputDuplication for the new content.
  • DXGI_ERROR_MORE_DATA if the buffer that the calling application provided is not big enough.
  • DXGI_ERROR_INVALID_CALL if the application called GetFrameMoveRects without owning the desktop image.
  • E_INVALIDARG if one of the parameters to GetFrameMoveRects is incorrect; for example, if pMoveRectBuffer is NULL.
  • Possibly other error codes that are described in the DXGI_ERROR topic.

Remarks

GetFrameMoveRects stores a size value in the variable at pMoveRectsBufferSizeRequired. This value specifies the number of bytes that GetFrameMoveRects needs to store information about moved regions. You can use this value in the following situations to determine the amount of memory to allocate for future buffers that you pass to pMoveRectBuffer:

  • GetFrameMoveRects fails with DXGI_ERROR_MORE_DATA because the buffer is not big enough.
  • GetFrameMoveRects supplies a buffer that is bigger than necessary. The size value returned at pMoveRectsBufferSizeRequired informs the caller how much buffer space was actually used compared to how much buffer space the caller allocated and specified in the MoveRectsBufferSize parameter.
The caller can also use the value returned at pMoveRectsBufferSizeRequired to determine the number of DXGI_OUTDUPL_MOVE_RECT structures returned.

The buffer contains the list of move RECTs for the current frame.

Note  To produce a visually accurate copy of the desktop, an application must first process all move RECTs before it processes dirty RECTs.
 

Requirements

Requirement Value
Minimum supported client Windows 8 [desktop apps only]
Minimum supported server Windows Server 2012 [desktop apps only]
Target Platform Windows
Header dxgi1_2.h
Library Dxgi.lib

See also

IDXGIOutputDuplication