请问用我自己给的坐标怎么在mapx上画线啊？代码如下

<P>void CAUTOCADTranslateView::DrawLine(float x1,float y1,float x2,float y2)
{
 CMapXFeature f;
 CMapXLayer lyr;
 CMapXPoints pts;
 CMapXPoint pt;
 CMapXStyle style;
 COleVariant vpts;
 COleVariant vstyle;
 double mx1,my1,mx2,my2;
 pts.CreateDispatch(pts.GetClsid());
 pt.CreateDispatch(pt.GetClsid()); pts.Add (pt);
 pt.Set(mx1,my1);
 pts.Add (pt);
 pt.Set(mx2,my2);
 pts.Add (pt);</P>
<P> vpts.vt = VT_DISPATCH;
 vpts.pdispVal = pts.m_lpDispatch;
 vpts.pdispVal->AddRef();</P>
<P> style=m_ctrlMapx.GetDefaultStyle();
 vstyle.vt = VT_DISPATCH;
 vstyle.pdispVal = style.m_lpDispatch;
 vstyle.pdispVal->AddRef();</P>
<P>
 lyr=m_ctrlMapx.GetLayers().Item(1);
 //f=m_ctrlMapx.GetFeatureFactory().CreateLine(vpts,vstyle);
 f=m_ctrlMapx.GetFeatureFactory().CreateRegion(vpts,vstyle);
 lyr.AddFeature (f);
}其中坐标x1,y1,x2,y2由自己给定，可是画出来的直线是水平的，还应该怎么做啊？谢谢
</P><img src="images/post/smile/dvbbs/em12.gif" />

<P>你确认你给得坐标没有超出你给定得地图坐标系得范围吗？
</P>

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