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IDDrawExclModeVideoCallback::OnUpdateOverlay

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Microsoft DirectShow 9.0

IDDrawExclModeVideoCallback::OnUpdateOverlay

The OnUpdateOverlay method informs the application when the overlay surface for the video is about to become visible, invisible, change size, or change position, so that the application can repaint its window appropriately.

Syntax

  HRESULT OnUpdateOverlay(
  BOOL bBeforeChange,
  DWORD dwFlags,
  BOOL bOldVisible,
  const RECT *prcSrcOld,
  const RECT *prcDestOld,
  BOOL bNewVisible,
  const RECT *prcSrcNew,
  const RECT *prcDestNew,
);

Parameters

bBeforeChange

[in] Boolean value specifying whether the call is being made before or after the overlay-related change. TRUE specifies before, FALSE specifies after.

dwFlags

[in] Value from the AM_OVERLAY_NOTIFY_FLAGS enumeration that specifies what is about to change or what changed.

bOldVisible

[in] Boolean value specifying whether the old window is visible. TRUE means the old window is visible.

prcSrcOld

[in] Pointer to the rectangle representing the old source position of the DirectDraw surface.

prcDestOld

[in] Pointer to the rectangle representing the old destination position of the rectangle in the overlay surface.

bNewVisible

[in] Boolean specifying whether the new window is visible. TRUE means the new window is visible.

prcSrcNew

[in] Pointer to the rectangle representing the new source position of the DirectDraw surface.

prcDestNew

[in] Pointer to the rectangle representing the new destination position of the rectangle in the overlay surface.

Return Values

Returns an HRESULT value. Possible values include the following.

Return code Description
S_OK Success.
E_INVALIDARG Invalid parameter.

Remarks

The application should call this method once before the overlay-related change occurs and once after the changes are done. In the call before the change, the overlay change doesn't happen until the application completes executing this method.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also