CBaseControlVideo.SetDefaultTargetRect method

Article
07/27/2023

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 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() = 0;

Parameters

This method has no parameters.

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

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