在开发的过程，要求cesium加载的地球透明

只是地表透明还不能满足要求，只加载部分区域的方式来解决的

代码如下：

<template>
	<div id="cesiumContainer" style="height: 100vh;"></div>
	<div id="toolbar" style="position: fixed;top:20px;left:220px;">
		<span style="color:#fff">球体透明</span>
	</div>
	<div class="slider-demo-block" style="width:200px;color:#fff;position: fixed;top:50px;left:220px;">
		<span class="demonstration">透明度</span>
		<el-slider v-model="value4" :format-tooltip="formatTooltip"/>
	</div>
</template>
<script setup>
import {ref, onMounted, nextTick} from 'vue'
import * as Cesium from 'cesium'

let viewer = null;
let value4 = ref(100);

// 倾斜摄影
onMounted(async () => {
	// token
	Cesium.Ion.defaultAccessToken = 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiJlNWM5ZjhhYi1iNDJhLTQ0OTMtYmQyOC1kYzhhNWVmYmMyZjMiLCJpZCI6MTUzOTk1LCJpYXQiOjE2ODkzNDgxNjN9.ar6bCmmT63fP9nBriZMfbAfPlRDKqIoCCl-ioDSeVN0'
	// 初始化
	viewer = new Cesium.Viewer('cesiumContainer', {
		orderIndependentTranslucency: false,
		contextOptions: {
			webgl: {
				alpha: true,
			}
		}
	});

	viewer.imageryLayers.removeAll();
	let imgLayer = new Cesium.UrlTemplateImageryProvider({
		url: "https://webst02.is.autonavi.com/appmaptile?style=6&x={x}&y={y}&z={z}",
		minimumLevel: 3,
		maximumLevel: 18
	})
	viewer.imageryLayers.addImageryProvider(imgLayer);

	// 地表透明
	viewer.scene.backgroundColor = Cesium.Color.BLACK.withAlpha(0);
	viewer.scene.globe.baseColor = Cesium.Color.BLACK.withAlpha(0); //修改地图蓝色背景
	viewer.scene.skyAtmosphere.show = false;
	viewer.scene.globe.translucency.enabled = true;
	viewer.scene.globe.undergroundColor = undefined;
	// 地表透明

	// 只显示部分地图  开始
	const globe = viewer.scene.globe;

	let clippingPlanesEnabled = true;
	let edgeStylingEnabled = false;

	const position = Cesium.Cartographic.toCartesian(
		new Cesium.Cartographic.fromDegrees(113.06785738392063, 22.643743971034342, 100)
	);
	const distance = 200000.0;
	const boundingSphere11 = new Cesium.BoundingSphere(position, distance);

	globe.clippingPlanes = new Cesium.ClippingPlaneCollection({
		modelMatrix: Cesium.Transforms.eastNorthUpToFixedFrame(position),
		planes: [
			new Cesium.ClippingPlane(
				new Cesium.Cartesian3(1.0, 0.0, 0.0),
				distance
			),
			new Cesium.ClippingPlane(
				new Cesium.Cartesian3(-1.0, 0.0, 0.0),
				distance
			),
			new Cesium.ClippingPlane(
				new Cesium.Cartesian3(0.0, 1.0, 0.0),
				distance
			),
			new Cesium.ClippingPlane(
				new Cesium.Cartesian3(0.0, -1.0, 0.0),
				distance
			),
		],
		unionClippingRegions: true,
		edgeWidth: edgeStylingEnabled ? 1.0 : 0.0,
		edgeColor: Cesium.Color.WHITE,
		enabled: clippingPlanesEnabled,
	});
	globe.backFaceCulling = false;
	globe.showSkirts = false;
	// 只显示部分地图  结束

	let tileset = await Cesium.Cesium3DTileset.fromUrl('/src/assets/tileset/12/tileset.json', {});

	update3dtilesMaxtrix(tileset);

	viewer.scene.primitives.add(tileset);
	await viewer.flyTo(tileset)

	//更新倾斜摄影位置
	function update3dtilesMaxtrix(tileSet) {
		//调整参数
		let params = {
			// tx: 113.06265738392063, //模型中心X轴坐标（经度，单位：十进制度）谷歌
			// ty: 22.646803971034342, //模型中心Y轴坐标（纬度，单位：十进制度）谷歌
			tx: 113.06785738392063, //模型中心X轴坐标（经度，单位：十进制度）高德
			ty: 22.643743971034342, //模型中心Y轴坐标（纬度，单位：十进制度）高德
			tz: 40, //模型中心Z轴坐标（高程，单位：米）
			rx: 0, //X轴（经度）方向旋转角度（单位：度）
			ry: 0, //Y轴（纬度）方向旋转角度（单位：度）
			rz: 2, //Z轴（高程）方向旋转角度（单位：度）
			scale: 1.3, //缩放比例
		};
		//旋转
		const mx = Cesium.Matrix3.fromRotationX(Cesium.Math.toRadians(params.rx));
		const my = Cesium.Matrix3.fromRotationY(Cesium.Math.toRadians(params.ry));
		const mz = Cesium.Matrix3.fromRotationZ(Cesium.Math.toRadians(params.rz));
		const rotationX = Cesium.Matrix4.fromRotationTranslation(mx);
		const rotationY = Cesium.Matrix4.fromRotationTranslation(my);
		const rotationZ = Cesium.Matrix4.fromRotationTranslation(mz);
		//平移
		const position = Cesium.Cartesian3.fromDegrees(
			params.tx,
			params.ty,
			params.tz
		);
		const m = Cesium.Transforms.eastNorthUpToFixedFrame(position);
		//旋转、平移矩阵相乘
		Cesium.Matrix4.multiply(m, rotationX, m);
		Cesium.Matrix4.multiply(m, rotationY, m);
		Cesium.Matrix4.multiply(m, rotationZ, m);
		//比例缩放
		const scale = Cesium.Matrix4.fromUniformScale(params.scale);
		Cesium.Matrix4.multiply(m, scale, m);
		console.log("矩阵m:", m);
		//赋值给tileset
		tileSet._root.transform = m;
	}
})

const formatTooltip = (val) => {
	nextTick(() => {
		// 地球球体透明
		var _layers = viewer.imageryLayers._layers;
		for (let i = 0, len = _layers.length; i < len; i++) {
			_layers[i].alpha = val / 100;
		}
	})
	// 地球球体透明
	return val / 100
}
</script>
<style scoped>
#cesiumContainer {
	overflow: hidden;
}

</style>

效果如图