cesium之直线类型

`
var viewer = new Cesium.Viewer("cesiumContainer", {
// 加入世界地形数据
terrainProvider: Cesium.createWorldTerrain({
requestWaterMask: true,
requestVertexNormals: true
}),
});

		var redLine = viewer.entities.add({
			// 贴在地面上 两点之间的直线距离
			name: "Red_line on terrain",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArray([-75, 35, -125, 35]),
				width: 10,
				// 不带箭头的线
				// material: Cesium.Color.RED,
				// 是否紧贴地面
				clampToGround: true,
				// 带箭头的线
				material: new Cesium.PolylineArrowMaterialProperty(
					Cesium.Color.RED
				),
			},
		});

		var greenRhumbLine = viewer.entities.add({
			name: "Green rhumb line",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArray([-75, 35, -125, 35]),
				width: 5,
				// arcType:多段线线段必须遵循的直线类型。
				// NONE:不符合椭球表面的直线。
				// GEODESIC:沿测地线路径。
				// RHUMB:沿着直角或斜线路径。
				arcType: Cesium.ArcType.RHUMB,
				material: Cesium.Color.GREEN,
			},
		});

		var glowingLine = viewer.entities.add({
			name: "Glowing blue line on the surface",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArray([-75, 37, -125, 37]),
				width: 10,
				material: new Cesium.PolylineGlowMaterialProperty({
					// 指定辉光强度的数字属性，以总线宽的百分比表示。
					glowPower: 0.7,
					// 一种数字特性，指定渐变效果的强度，以占总线条长度的百分比表示。如果为1.0或更高，则不使用锥度效果。
					taperPower: 0.6,
					color: Cesium.Color.RED,
				}),
			},
		});

		var orangeOutlined = viewer.entities.add({
			name: "Orange line with black outline at height and following the surface",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArrayHeights([
					-75, 39, 250000,
					-125, 39, 250000,
				]),
				width: 5,
				// arcType: Cesium.ArcType.RHUMB,
				// arcType: Cesium.ArcType.GEODESIC,
				material: new Cesium.PolylineOutlineMaterialProperty({
					color: Cesium.Color.ORANGE,
					outlineWidth: 2,
					outlineColor: Cesium.Color.BLACK,
				}),
			},
		});

		var purpleArrow = viewer.entities.add({
			name: "Purple straight arrow at height",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArrayHeights([
					-75, 43, 500000,
					-125, 43, 500000,
				]),
				width: 10,
				arcType: Cesium.ArcType.NONE,
				// 带箭头的直线
				// material: new Cesium.PolylineArrowMaterialProperty(
				// 	Cesium.Color.PURPLE
				// ),
				// 不带箭头的直线
				material: Cesium.Color.PURPLE
				
			},
		});

		var dashedLine = viewer.entities.add({
			name: "Blue dashed line",
			polyline: {
				positions: Cesium.Cartesian3.fromDegreesArrayHeights([
					-75, 45, 500000,
					-125, 45, 500000,
				]),
				width: 4,
				// 普通的直线
				// PolylineGlowMaterialProperty
				// 虚线
				// PolylineDashMaterialProperty
				// 多段线轮廓材质属性
				// PolylineOutlineMaterialProperty
				material: new Cesium.PolylineOutlineMaterialProperty({
					color: Cesium.Color.CYAN,
				}),
			},
		});

		viewer.zoomTo(viewer.entities);`