为什么有时候出现out the memory

var
ft,ftr1,ft1:cmapxfeature; 
    fs:cmapxfeatures;               
    j,cnt:integer;
    pt1,pt2:Cmapxpoint;
    obj:variant;                       //  相交的图元
    arrVals: Variant;                  //  节点
    r:double;
    x,y:array of array of double;      //  x,y:中心线的节点,第一维表示节点的序号，第二维表示选择的图元序号;
    x1,y1:array of double
    x2,y2:double;                      //  所有相交图元中最短距离的点
    nodecnt:integer;                   //  记录所有相交图元的节点
    dd,tt:double;                         //  中间变量
    dist,d:double; 
beginft:=map1.FeatureFactory.CreateCircularRegion(1,pt,radiu,miUnitMeter,24,map1.DefaultStyle);             //以接收到的点做圆
                 fs:=map1.Layers.Item['街道中心线'].SearchWithinDistance(pt,radiu+30,miUnitMeter,1);   //接收点200米范围内的街道中心线的所有图元                //////////////画最短路径
              tt:=1000000;
              if fs.Count>0 then
                begin
                 setlength(x1,fs.Count);
                 setlength(y1,fs.Count);
                 for j:=1 to fs.Count do
                   begin
                     ftr1:=fs.Item[j];
                     
                     if map1.FeatureFactory.IntersectionTest(ftr1,ft,miintersectfeature) then
                       begin
                         if ftr1.Type_=1 then
                           begin
                             setlength(x,ftr1.Parts.Item[1].Count,fs.Count);
                             setlength(y,ftr1.Parts.Item[1].Count,fs.Count);                             dd:=1000000;
                             for i:=1 to ftr1.Parts.Item[1].Count do
                               begin
                                 x[i-1,j-1]:=ftr1.Parts.Item[1].Item[i].X;
                                 y[i-1,j-1]:=ftr1.Parts.Item[1].Item[i].Y;                                 dist:=map1.Distance(x[i-1,j-1],y[i-1,j-1],pt.X,pt.Y);//接收点与中心线节点的距离
                                 //求最短路径的点
                                 if dist<dd then
                                   begin
                                     x1[j-1]:=x[i-1,j-1];
                                     y1[j-1]:=y[i-1,j-1];
                                     dd:=dist;
                                   end;
                               end;
                           end
                         else
                           continue;
                     d:=map1.Distance(x1[j-1],y1[j-1],pt.X,pt.Y);
                     if d<tt then
                       begin
                         x2:=x1[j-1];
                         y2:=y1[j-1];
                         tt:=d;
                       end;
                   end;//endfor   j                 end; //end  if fs>0                       //x2,y2是要求的匹配的点
                   if int(x2)<>0  then
                     begin
                       v_temp.longitude:=x2;
                       v_temp.latitude:=y2;
                       pt.Set_(x2,y2);
                     end;
                  varclear(obj);
                  varclear(arrvals);
end;