Cesium learning (III): Load Default Line

// 加载默认线条
	function initShowLine(){
		var objId = "line_one";
		var positions = 
		[
			{x: -2027365.029498278, y: 5643501.100524499, z: 2165534.2688970272},
			{x: -2031395.0770982248, y: 5642066.230989595, z: 2165515.129923677}
		];
		initShowPolyline(objId, positions);
		
		objId = "line_two";
		positions = 
		[
			{x: -2027365.029498278, y: 5643501.100524499, z: 2165534.2688970272},
			{x: -2028892.7635749679, y: 5642759.580495446, z: 2166045.548750987},
			{x: -2030175.7696807438, y: 5642306.50626273, z: 2166023.2324521956},
			{x: -2031395.0770982248, y: 5642066.230989595, z: 2165515.129923677}
		];
		initShowPolyline(objId, positions);
		
		objId = "line_three";
		positions = 
		[
			{x: -2027365.029498278, y: 5643501.100524499, z: 2165534.2688970272},
			{x: -2027883.9406702125, y: 5643590.070223619, z: 2164821.443483807},
			{x: -2030807.9534780958, y: 5642564.539566782, z: 2164780.8840529644},
			{x: -2031395.0770982248, y: 5642066.230989595, z: 2165515.129923677}
		];
		initShowPolyline(objId, positions);
	}
	
	// 展示线条
	function initShowPolyline(objId, positions) {
		var lineColor = '#00f';
		if(objId == "1"){
			lineColor = "#E90808";
		}else if(objId == "2"){
			lineColor = "#22E908";
		}else if(objId == "3"){
			lineColor = "#0815E9";
		}
		
		var material = new Cesium.PolylineGlowMaterialProperty({
			glowPower: 0.25,
			color: Cesium.Color.fromCssColorString(lineColor).withAlpha(0.9)
		});
		var bData = {
			layerId: layerId,
			objId: objId,
			shapeType: "Polyline",
			polyline: {
				positions: positions,
				clampToGround: true,
				width: 8,
				material: material
			}
		};
		var entity = viewer.entities.add(bData);
	}