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CBaseControlVideo::SetDefaultSourceRect

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Microsoft DirectShow 9.0

CBaseControlVideo::SetDefaultSourceRect

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

Syntax

  virtual HRESULT SetDefaultSourceRect(void) PURE;

Return Value

Returns an HRESULT value.

Remarks

Derived classes should override this to reset the source rectangle. It is called from CBaseControlVideo::SetDefaultSourcePosition.

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

// This is called when you reset the default source rectangle.
HRESULT CVideoText::SetDefaultSourceRect()
{
    VIDEOINFO *pVideoInfo = (VIDEOINFO *) m_pRenderer->m_mtIn.Format();
    BITMAPINFOHEADER *pHeader = HEADER(pVideoInfo);
    RECT SourceRect = {0,0,pHeader->biWidth,pHeader->biHeight};
    m_pRenderer->m_DrawImage.SetSourceRect(&SourceRect);
    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 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