To understand the mfc dialog, onpaint better, after reading some online notes, made a little project. This draws a Horz. axis with a red color curve above it. What I can not figure how to do, is to redraw the whole thing multiple times with each time the whole plot moves. Like erase/redraw thing. don't know how to erase and redraw.
Code:void MyDraw::OnPaint()
{
CPaintDC dc(this);
DrawC(dc);
}
void MyDraw::DrawC(CDC& dc)
{
CRect rect;
GetClientRect(rect);
HDC hdc = dc.GetSafeHdc();
CPen aPen, dkpen, redPen;
aPen.CreatePen(PS_SOLID, 2, RGB(255, 225, 225));
dkpen.CreatePen(PS_SOLID, 1, RGB(0, 0, 0));
redPen.CreatePen(PS_SOLID, 1, RGB(255, 0, 0));
CPen* pOldPen = dc.SelectObject(&aPen);
CPen* gOldPen = dc.SelectObject(&dkpen);
dc.MoveTo(10,250);
dc.LineTo(220,250);
dc.MoveTo(220,250);
dc.LineTo(215,255);
dc.MoveTo(220,250);
dc.LineTo(215,245);
gOldPen = dc.SelectObject(&redPen);
dc.MoveTo(10, 250);
dc.LineTo(100, 220);
dc.LineTo(150, 200);
dc.LineTo(190, 160);
dc.LineTo(195, 130);
}

