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CBaseControlVideo::SetDefaultTargetRect

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Microsoft DirectShow 9.0

CBaseControlVideo::SetDefaultTargetRect

The SetDefaultTargetRect method sets the default target video rectangle (pure virtual). This is an internal member function that gets called when the source rectangle is reset.

Syntax

  virtual HRESULT SetDefaultTargetRect(void) PURE;

Return Value

Returns an HRESULT value.

Remarks

Derived classes should override this to reset the destination video rectangle. It is called from the CBaseControlVideo::SetDefaultDestinationPosition member function.

The following example demonstrates an implementation of this function in a derived class.

// This is called when you reset the default target rectangle.
HRESULT CVideoText::SetDefaultTargetRect()
{
    VIDEOINFO *pVideoInfo = (VIDEOINFO *) m_pRenderer->m_mtIn.Format();
    BITMAPINFOHEADER *pHeader = HEADER(pVideoInfo);
    RECT TargetRect = {0,0,m_Size.cx,m_Size.cy};
    m_pRenderer->m_DrawImage.SetTargetRect(&TargetRect);
    return NOERROR;
}

In this example, CVideoText is a class derived from CBaseControlVideo, m_pRenderer holds an object of a class derived from CBaseVideoRenderer, and the m_DrawImage data member, defined in the derived class, holds a CDrawImage object. The m_mtIn data member, also defined in the derived class, holds a CMediaType object with the media type of the input pin.

Requirements

**  Header:** Declared in Ctlutil.h; include Streams.h.

**  Library:** Use Strmbase.lib (retail builds) or Strmbasd.lib (debug builds).

See Also