C / C++ / MFC

Redeye92 wrote:

I've tried doing a GDI BitBlt() instead but while that function is fast, the creation of the HDC and HBITMAP and everything else needed isn't, and there's no speed advantage.

m_pbmpMemory->GetHBITMAP(Color::White, &m_hMemBitmap);
m_hMemHDC = m_gr->GetHDC();
SelectObject(m_hMemHDC, m_hMemBitmap);
BitBlt(pDC->m_hDC, rcPaint.left, rcPaint.top, rcPaint.Width(), rcPaint.Height(),
    m_hMemHDC, rcPaint.left, rcPaint.top, SRCCOPY);
m_gr->ReleaseHDC(m_hMemHDC);

Redeye92 wrote:

I just can't see how to keep a hold of the HDC and HBITMAP between calls to OnPaint(),

void MyDlg::CreateMemDC( CDC* pRefDC, int nWidth, int nHeight )
{
  m_dcMem.CreateCompatibleDC( pRefDC );
  m_bitmapMem.CreateCompatibleBitmap( pRefDC, nWidth, nHeight );
  m_dcMem.SelectObject( &m_bitmapMem );
}

void MyDlg::OnInitDlg()
{
  // some code
  CClientDC dc( this );
  CreateMemDC( &dc, 300, 200 ); // or what ever size you needed
  // draw the image to this m_dcMem
}

void MyDlg::OnPaint()
{
  BitBlt( pDC->m_hDC, .... .... ... , m_dcMem.m_hDC, ...... );
}

<br />
        // Get a device context for painting<br />
	CPaintDC dc(this);<br />
	if(!m_pMemDC)<br />
	{<br />
		vUpdateBitmap(&dc);<br />
	}<br />
	// Get the client rect<br />
	CRect rcClientRect;<br />
	GetClientRect(&rcClientRect);<br />
        // Get the actual width of the view we want to draw<br />
	ULONG32 ulViewWidth = ulGetViewWidth();<br />
	// If the window size has changed for any reason, we need to redraw the bitmap<br />
        // Put your if statement here.<br />
	{<br />
		vUpdateBitmap(&dc);<br />
	}<br />
	// Get the invalid rectangle<br />
	CRect rcPaint;<br />
	dc.GetClipBox(rcPaint);<br />
	// Then just copy the bit of the memory bitmap that we need<br />
	dc.BitBlt(rcPaint.left, rcPaint.top, rcPaint.Width(), rcPaint.Height(),<br />
		m_pMemDC, rcPaint.left, rcPaint.top, SRCCOPY);<br />

<br />
<br />
		// Recreate the memory bitmap and graphics objects<br />
		if(pDC)<br />
		{<br />
			if(m_pMemDC)<br />
			{<br />
				delete m_pMemDC;<br />
			}<br />
			m_pMemDC = new CDC;<br />
			// Make a compatible DC<br />
			m_pMemDC->CreateCompatibleDC(pDC);;<br />
			<br />
			// Create a new bitmap<br />
			CBitmap *m_pNewBitmap;<br />
			m_pNewBitmap = new CBitmap;<br />
			// Create the new bitmap<br />
			m_pNewBitmap->CreateCompatibleBitmap(pDC, rcClient.Width(), rcClient.Height());<br />
			m_pNewBitmap->SetBitmapDimension(rcClient.Width(), rcClient.Height());<br />
			// Select the new bitmap into the memory DC<br />
			m_pMemDC->SelectObject(m_pNewBitmap);<br />
			// Delete the old one<br />
			delete m_pbmpMemBitmap;<br />
			// Reset the view pointer<br />
			m_pbmpMemBitmap = m_pNewBitmap;<br />
			if(m_gr)<br />
			{ delete m_gr; }<br />
			m_gr = Graphics::FromHDC(m_pMemDC->m_hDC);<br />
		}<br />

Address of an array of pointers to ITEMIDLIST structures, each of which uniquely identifies a file object or subfolder relative to the parent folder. Each item identifier list must contain exactly one SHITEMID structure followed by a terminating zero.

nekokan wrote:

When i set it as 2 and i set data (for output) at even point as 0, sound output in left side but sound output is different from i set numOutputChannel as 1.

vikrams wrote:

Now as logging code will be present in my binary during release time,
this will enforce some types of checks even if the logging is not
enabled which will lead to CPU cost.

#define LOG(x) if( bLogEnabled ) { LogString( x ); }