iClient9D for openlayers上有个加载平面坐标系底图的例子,
问题一:这样写不能显示地图:
source: new ol.source.TileSuperMapRest({
                url: url,
                wrapX: false
            })
报错: Cannot read property 'getOrigin' of null
问题二:这个方式建的投影,添加的比例尺有问题,比例尺非常大
var projection = new ol.proj.Projection({
        extent: extent,
        units: 'm'
    });