Graphics g(pDc->m_hDC);
g.SetSmoothingMode(SmoothingModeHighQuality);
Color* attibute_color=(Color*)m_attributes[1]->pData;
Color color(attibute_color->GetAlpha(),attibute_color->GetRed(),attibute_color->GetGreen(),attibute_color->GetBlue());
int line_width=m_attributes[0]->intvalue;
Pen pen(color,line_width);
//设置箭头大小
AdjustableArrowCap cap(4,4,true);
pen.SetCustomEndCap(&cap);
CPoint srcpoint = GetSrcPoint();
CPoint destpoint = GetDestPoint();
g.DrawLine(&pen,srcpoint.x,srcpoint.y,destpoint.x,destpoint.y);