CBaseControlVideo.SetSourceRect method

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The SetSourceRect method sets the current source video rectangle (pure virtual). This is an internal member function that gets called when the source rectangle changes.

Syntax

virtual HRESULT SetSourceRect(
   RECT *pSourceRect
) = 0;

Parameters

pSourceRect

Pointer to the source rectangle.

Return value

Returns an HRESULT value.

Remarks

Derived classes should override this member function to know when the source rectangle changes. It is called from the following member functions.

• CBaseControlVideo::SetSourcePosition
• CBaseControlVideo::put_SourceLeft
• CBaseControlVideo::put_SourceWidth
• CBaseControlVideo::put_SourceTop
• CBaseControlVideo::put_SourceHeight

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

HRESULT CVideoText::SetSourceRect(RECT *pSourceRect)
{
    m_pRenderer->m_DrawImage.SetSourceRect(pSourceRect);
    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.

Requirements

Requirement	Value
Header	Ctlutil.h (include Streams.h)
Library	Strmbase.lib (retail builds); Strmbasd.lib (debug builds)

See also

CBaseControlVideo Class