您好,
您可以参考下这篇博客:http://blog.csdn.net/u013929284/article/details/52653084    (9.其他问题  ②贴地线)
矢量面贴地的代码 //自定义polygon
        var polygon = viewer.entities.add({
            polygon : {
                hierarchy : {
                    positions : [new Cesium.Cartesian3(290254.5148736448,5637924.074937166,2971777.4768239637),
                        new Cesium.Cartesian3(286432.14053509803,5640804.651089405,2966391.9275969476),
                        new Cesium.Cartesian3(283512.2666752818,5640502.494127799,2969385.3689191523),
                        new Cesium.Cartesian3(287036.36797237827,5636827.146248645,2974105.8904601005)]
                },
                material : Cesium.Color.BLUE.withAlpha(0.5)
            }
        });