Drawing rectangle/lines using PatBlt - mfc

Question

I am drawing ruler using the sample application given in the link.
http://www.ucancode.net/Visual_C_Source_Code/MFC-MDI-SDI-Example-create-ruler-scrollview-splitter.htm
On moving cursor they are drawing black line marker. I want to draw red color line like in microsoft paint application.
In the sample they are using below code for drawing line.
What needs to be done to draw red color line.
void CRulerView::DrawCursorPos(CPoint NewPos)
{
if (((m_rulerType == RT_HORIZONTAL) && (NewPos.x > m_DocSize.cx*m_fZoomFactor)) ||
((m_rulerType == RT_VERTICAL) && ((NewPos.y) > m_DocSize.cy*m_fZoomFactor)))
return;
CDC* pDC = GetDC();
// set the map mode right
int oldMapMode = pDC->SetMapMode(MM_TEXT);
//HBRUSH hBr=CreateSolidBrush(RGB(255,0,0));
//pDC->SelectObject(hBr);
//CBrush* pTempBrush = NULL;
// pTempBrush = (CBrush*)pDC->SelectObject(&hBr);
CRect clientRect;
GetClientRect(&clientRect);
if (m_rulerType==RT_HORIZONTAL)
{
// erase the previous position
pDC->PatBlt(m_lastPos.x, clientRect.top, 1, clientRect.bottom, DSTINVERT);
// draw the new position
m_lastPos.x = NewPos.x;
pDC->PatBlt(m_lastPos.x, clientRect.top, 1, clientRect.bottom, DSTINVERT);
}
else // (m_rulerType==RT_VERTICAL)
{
// erase the previous position
pDC->PatBlt(clientRect.left, m_lastPos.y, clientRect.right, 1, DSTINVERT);
// draw the new position
m_lastPos.y = NewPos.y;
pDC->PatBlt(clientRect.left, m_lastPos.y, clientRect.right, 1, DSTINVERT);
}
//pDC->SelectObject(&pTempBrush);
pDC->SetMapMode(oldMapMode);
ReleaseDC(pDC);
}