can multiple thermal maps be added to Baidu map? if I add one, I can"t see
heatmapOverlay = new BMapLib.HeatmapOverlay ({"radius": 30});
map.addOverlay (heatmapOverlay);
heatmapOverlay.setDataSet ({data:points,max:100});
heatmapOverlay1 = new BMapLib.HeatmapOverlay({"radius":20});
map.addOverlay(heatmapOverlay1);
heatmapOverlay1.setDataSet({data:points1,max:100});