Javascript 铯原子中实体多边形和基元多边形的区别

最近我尝试在铯沙堡中创建一个红色多边形。一般来说，绘制多边形有三种方法：从czml文件、从实体和从基本体。然而，来自实体的多边形和来自基本体的多边形是不同的。当我从不同方向观察它们时，基本体中多边形的透明度会改变，而实体中多边形的透明度不会改变。这让我很困惑。我的代码如下：

//create a cyan polygon from entity
var cyanPolygon = viewer.entities.add({
  name: "cyanPolygon",
  polygon: {
    hierarchy: Cesium.Cartesian3.fromDegreesArrayHeights([
      -72.0, 30.0, 100000,
      -64.0, 25.0, 100000,
      -72.0, 20.0, 100000
    ]),
    perPositionHeight: true,
    material: Cesium.Color.RED.withAlpha(0.3)
  },
});
//create a cyan polygon from primitive
var Points = viewer.scene.primitives.add(new Cesium.PrimitiveCollection());
Points.add(new Cesium.Primitive({
  geometryInstances: new Cesium.GeometryInstance({
    geometry: new Cesium.PolygonGeometry({
      polygonHierarchy: new Cesium.PolygonHierarchy(
        Cesium.Cartesian3.fromDegreesArrayHeights([
          -72.0, 40.0, 100000,
          -64.0, 35.0, 100000,
          -72.0, 30.0, 100000
        ])
      ),
      perPositionHeight: true,
      closeTop:false
    }),
    id: 'Polygon',
    attributes: {
      color: new Cesium.ColorGeometryInstanceAttribute(1, 0, 0, 0.3)
    }
  }),
  appearance: new Cesium.PerInstanceColorAppearance({
    closed: true
  })
}));```

[enter image description here][1]
[enter image description here][2]


  [1]: https://i.stack.imgur.com/IeUl6.jpg
  [2]: https://i.stack.imgur.com/UofnN.jpg