C / C++ / MFC

//draw window background with gdi+ and UpdateLayerdWindow
void CWindowAnimateDlg::DrawBackground()
{
	CDC* dc=this->GetWindowDC();
	HDC hdcMemory=CreateCompatibleDC(dc->GetSafeHdc());
	
	CRect rct;
	GetWindowRect(&rct);
	//{
		BITMAPINFO bmih;
		ZeroMemory( &bmih, sizeof( BITMAPINFO ) );
		bmih.bmiHeader.biSize                  = sizeof (BITMAPINFOHEADER) ;
		bmih.bmiHeader.biWidth                = rct.Width() ;
		bmih.bmiHeader.biHeight                = rct.Height() ;
		bmih.bmiHeader.biPlanes                = 1 ;
		bmih.bmiHeader.biBitCount              = 32;        
		bmih.bmiHeader.biCompression          = BI_RGB ;
		bmih.bmiHeader.biSizeImage            = 0 ;
		bmih.bmiHeader.biXPelsPerMeter        = 0 ;
		bmih.bmiHeader.biYPelsPerMeter        = 0 ;
		bmih.bmiHeader.biClrUsed              = 0 ;
		bmih.bmiHeader.biClrImportant          = 0 ;

	//}

	HBITMAP hBitMap;
	hBitMap = CreateDIBSection (NULL,   &bmih, 0, NULL, NULL, 0) ;

	HBITMAP oldBitmap=(HBITMAP)SelectObject(hdcMemory,hBitMap);

	//GDI+
	Graphics gpc(hdcMemory);
	gpc.SetCompositingMode(CompositingModeSourceCopy);

	DWORD dwExStyle=GetWindowLong(m_hWnd,GWL_EXSTYLE);
    SetWindowLongA(m_hWnd,GWL_EXSTYLE,dwExStyle|WS_EX_LAYERED);
	
	HDC hdcScreen=::GetDC(m_hWnd);
	CDC cdc;
    cdc.Attach(hdcScreen);
    CDC cdc2;
    cdc2.Attach(hdcMemory);

	if(m_bkImage)
	{
		gpc.DrawImage(
			m_bkImage,
			Rect(0,0,rct.Width(),rct.Height()),
			0,0,m_bkImage->GetWidth(),m_bkImage->GetHeight(),
			UnitPixel
			);
	}

	POINT ptWinPos={rct.left,rct.top};
	POINT ptSrc={0,0};
	SIZE sizeWindow={rct.Width(),rct.Height()};
	BLENDFUNCTION blend;
	blend.BlendOp=0; 
    blend.BlendFlags=0; 
    blend.AlphaFormat=AC_SRC_ALPHA; 
	blend.SourceConstantAlpha=255;

	UpdateLayeredWindow( &cdc,&ptWinPos,
                        &sizeWindow,&cdc2,&ptSrc,0,&blend,ULW_ALPHA);

	::SelectObject(hdcMemory,oldBitmap);
	ReleaseDC(dc);
	gpc.ReleaseHDC(hdcMemory);
    ::ReleaseDC(m_hWnd,hdcScreen);
	DeleteObject(hBitMap);
    DeleteDC(hdcMemory);
    hdcMemory=NULL;

}


void CWindowAnimateDlg::OnTimer(UINT_PTR nIDEvent)
{
	switch(nIDEvent)
	{
	case 1:
		{
			CRect rect;
			GetWindowRect(&rect);
			CRect nRect;
			int l,t,r,b;
			l=m_targetRect.left-rect.left;
			t=m_targetRect.top-rect.top;
			r=m_targetRect.right-rect.right;
			b=m_targetRect.bottom-rect.bottom;

			nRect.SetRect(//next place .non linear fade
				rect.left+(l>0?l/5+1:l/5-1),
				rect.top+(t>0?t/5+1:t/5-1),
				rect.right+(r>0?r/5+1:r/5-1),
				rect.bottom+(b>0?b/5+1:b/5-1)
			);
			if(//very close target place
				abs(l)<2&&
				abs(t)<2&&
				abs(r)<2&&
				abs(b)<2
				)
			{
				KillTimer(1);
				MoveWindow(&m_targetRect);
				break;
			}
			MoveWindow(&nRect);
		}
	}
	CDialog::OnTimer(nIDEvent);
}

void CWindowAnimateDlg::OnWindowPosChanged(WINDOWPOS* lpwndpos)
{
	CDialog::OnWindowPosChanged(lpwndpos);
	if(!(lpwndpos->flags&SWP_NOSIZE))
		DrawBackground();
}

void CWindowAnimateDlg::OnLButtonDown(UINT nFlags, CPoint point)
{
	if(m_state==1)
	{
		m_state=2;
		m_targetRect.SetRect(550,300,650,400);
		SetTimer(1,30,NULL);
	}
	else if(m_state==2)
	{
		m_state=1;
		m_targetRect.SetRect(150,150,950,550);
		SetTimer(1,30,NULL);
	}
	CDialog::OnLButtonDown(nFlags, point);
}