C / C++ / MFC

<br />
	// Kode for å tegne opp rapporten<br />
<br />
	// Beregner området å tegne i<br />
	CRect rect;<br />
	GetClientRect(&rect);<br />
	int nWidth = rect.right - rect.left +1;<br />
	int nHeight = rect.bottom - rect.top + 1;<br />
<br />
	CClientDC ClientDC(this);<br />
	Graphics graphics(ClientDC.m_hDC);	// GDI+ Stuff graph(ClientDC.m_hDC);<br />
<br />
	// Test for drawing with double buffering<br />
        // Bitmap* bmp = new Bitmap(nWidth,nHeight); and<br />
        // Bitmap* bmp(nWidth,nHeight); seems to give the same results...<br />
	#ifdef _DEBUG<br />
	#undef new<br />
		Bitmap* bmp = new Bitmap(nWidth,nHeight);<br />
	#define new DEBUG_NEW<br />
	#else<br />
		Bitmap* bmp = new Bitmap(nWidth,nHeight);<br />
	#endif<br />
		Graphics* graph = Graphics::FromImage(bmp);<br />
	<br />
	CRect area( 0, 0, 0, 0);<br />
<br />
        // This works, no questions asked, but it's not double buffering<br />
	area.SetRect( 8, 90, 814, 90); // Skillelinje som skiller elevdata fra resten av skjemaet<br />
	DrawLine(&graphics, area, 1);<br />
<br />
	/*       Test drawing to test double buffering */<br />
	// Takes about 10 seconds without double buffering<br />
	// Takes about xx seconds with double buffering<br />
	Pen pen(Color(200,0,0, 50));<br />
	for( int j=100; j<500;j = j + 5) {<br />
		for (int i=100; i<500; i = i + 5) {<br />
			area.SetRect( 110,110, j, i);<br />
<br />
                        // This works.<br />
			DrawLine(&graphics, area, 1);<br />
<br />
                        // This line causes the crach, when commented out, the code does what it's supposed to do<br />
			// graph->DrawLine(&pen, area.left, area.top, area.Width(), area.Height());<br />
		}<br />
	}<br />
<br />
	graphics.DrawImage( bmp, 0,0, 600, 600);<br />
	delete graph;<br />
	delete bmp;<br />
	/*       End test drawing       */<br />

<br />
void CITPAXpertView::DrawLine(Graphics *pdc, CRect rect, int width)<br />
{<br />
	// Beregner hvor vi er "i landskapet" når det gjelder scrolling<br />
	CPoint where = GetDeviceScrollPosition();<br />
<br />
	// Lager en penn å tegne med<br />
	Pen penn(Color(0,0,0), REAL(width));<br />
<br />
	// Takes care of drawing lines<br />
	pdc->DrawLine( &penn, rect.left - where.x, rect.top - where.y, rect.right - where.x, rect.bottom - where.y);<br />
}<br />