MapX遇到的一个奇怪的问题，高手帮忙看看

我用vc+MapX  要实现一个鹰眼图的功能，现在遇到的问题是：当在小地图上画矩形框的时候，画出来的不是矩形 而是一个菱形，线都是斜的 很奇怪  部分代码如下，高手帮忙解释一下：
extern CRect g_ctrlMapCoord; VARIANT scrLeft,scrTop,scrRight,scrBottom; 
VARIANT mapLeft,mapTop,mapRight,mapBottom; 
double  eagelLeft,eagelTop,eagelRight,eagelBottom; 
double  left,top,right,bottom; 
eagelLeft= eagelTop = eagelRight= eagelBottom = 0;
left=g_ctrlMapCoord.left; 
top=g_ctrlMapCoord.top; 
right=g_ctrlMapCoord.right; 
bottom=g_ctrlMapCoord.bottom;  CMapXStyle  style; 
CMapXLayer  layer; 
CMapXFeatures  features; 
CMapXFeature  feature; 
static CMapXFeature m_eagelFeature;
CMapXFeatureFactory  factory; 
CMapXParts  parts; 
CMapXPoints  points; 
points.CreateDispatch(points.GetClsid()); 
//进行坐标变换 
m_smallMap.ConvertCoordV(&scrLeft,&scrTop,COleVariant(left),COleVariant(top),miMapToScreen);
m_smallMap.ConvertCoordV(&scrRight,&scrBottom,COleVariant(right),COleVariant(bottom),miMapToScreen); 
m_smallMap.ConvertCoordV(&scrLeft,&scrTop,&mapLeft,&mapTop,miScreenToMap); 
m_smallMap.ConvertCoordV(&scrRight,&scrBottom,&mapRight,&mapBottom,miScreenToMap); 
eagelLeft = mapLeft.dblVal; 
eagelTop =mapTop.dblVal; 
eagelRight =mapRight.dblVal; 
eagelBottom  = mapBottom.dblVal; 
//获得添加矩形框的图层 
layer =m_smallMap.GetLayers().Item("DynRect"); 
features= layer.AllFeatures(); 
//若图层上没有矩形框 ,则新建 
if(features.GetCount()==0) 
{ 
points.AddXY(eagelLeft,eagelTop); 
points.AddXY(eagelRight,eagelTop); 
points.AddXY(eagelRight,eagelBottom); 
points.AddXY(eagelLeft,eagelBottom);  COleVariant vtPoints; 
vtPoints.vt = VT_DISPATCH;
vtPoints.pdispVal = points.m_lpDispatch;
vtPoints.pdispVal->AddRef(); 
style= layer.GetStyle(); 
style.SetRegionPattern(miPatternNoFill);
style.SetRegionBorderColor(miColorRed); 
style.SetRegionBorderWidth(2); 
COleVariant vtStyle; 
vtStyle.vt= VT_DISPATCH ; 
vtStyle.pdispVal  = style.m_lpDispatch;
vtStyle.pdispVal->AddRef(); 
factory= m_smallMap.GetFeatureFactory();
feature= factory.CreateRegion(vtPoints,vtStyle); 
m_eagelFeature= layer.AddFeature (feature.m_lpDispatch); 
} 
else //否则更新矩形框的位置或大小 
{ 
points.AddXY(eagelLeft,eagelTop);
points.AddXY(eagelRight,eagelTop); 
points.AddXY(eagelRight,eagelBottom);
points.AddXY(eagelLeft,eagelBottom); 
parts=m_eagelFeature.GetParts(); 
parts.RemoveAll(); 
parts.Add(points); 
m_eagelFeature.Update();
}
layer.Refresh();