三 是否可以制作透明着色器？

camera = new THREE.PerspectiveCamera(60, window.innerWidth / window.innerHeight, 1, 100000);
camera.position.z = 3200;
//
var path = "https://threejs.org/examples/textures/cube/Park2/";
var format = '.jpg';
var urls = [
  path + 'posx' + format, path + 'negx' + format,
  path + 'posy' + format, path + 'negy' + format,
  path + 'posz' + format, path + 'negz' + format
];
var textureCube = new THREE.CubeTextureLoader().load(urls);
textureCube.format = THREE.RGBFormat;
scene = new THREE.Scene();
scene.background = textureCube;
//
var geometry = new THREE.SphereBufferGeometry(100, 32, 16);
var shader = THREE.FresnelShader;
var uniforms = THREE.UniformsUtils.clone(shader.uniforms);
uniforms["tCube"].value = textureCube;
var material = new THREE.ShaderMaterial({
  uniforms: uniforms,
  vertexShader: shader.vertexShader,
  fragmentShader: shader.fragmentShader,
  transparent: true
});

var mesh = new THREE.Mesh(geometry, material);
mesh.scale.x = mesh.scale.y = mesh.scale.z = 10;
scene.add(mesh);

var renderer = new THREE.WebGLRenderer();
renderer.setClearColor(0x404040);
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);

var light = new THREE.DirectionalLight(0xffffff, 0.5);
light.position.setScalar(10);
scene.add(light);
scene.add(new THREE.AmbientLight(0xffffff, 0.5));

var box = new THREE.Mesh(new THREE.BoxGeometry(600, 600, 600), new THREE.MeshLambertMaterial({
  color: "white"
}));
scene.add(box);

var controls = new THREE.OrbitControls(camera, renderer.domElement);

var animate = function() {
  requestAnimationFrame(animate);
  box.rotation.x += 0.01;
  box.rotation.y += 0.03;
  renderer.render(scene, camera);
};

animate();

body {
  overflow: hidden;
  margin: 0;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/96/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js"></script>
<script>
  THREE.FresnelShader = {

    uniforms: {

      "mRefractionRatio": {
        value: 1.02
      },
      "mFresnelBias": {
        value: 0.1
      },
      "mFresnelPower": {
        value: 2.0
      },
      "mFresnelScale": {
        value: 1.0
      },
      "tCube": {
        value: null
      },
      "alpha": { //добавленная униформа для прозрачности
        value: 0.0625
      }

    },

    vertexShader: [

      "uniform float mRefractionRatio;",
      "uniform float mFresnelBias;",
      "uniform float mFresnelScale;",
      "uniform float mFresnelPower;",

      "varying vec3 vReflect;",
      "varying vec3 vRefract[3];",
      "varying float vReflectionFactor;",

      "void main() {",

      "vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );",
      "vec4 worldPosition = modelMatrix * vec4( position, 1.0 );",

      "vec3 worldNormal = normalize( mat3( modelMatrix[0].xyz, modelMatrix[1].xyz, modelMatrix[2].xyz ) * normal );",

      "vec3 I = worldPosition.xyz - cameraPosition;",

      "vReflect = reflect( I, worldNormal );",
      "vRefract[0] = refract( normalize( I ), worldNormal, mRefractionRatio );",
      "vRefract[1] = refract( normalize( I ), worldNormal, mRefractionRatio * 0.99 );",
      "vRefract[2] = refract( normalize( I ), worldNormal, mRefractionRatio * 0.98 );",
      "vReflectionFactor = mFresnelBias + mFresnelScale * pow( 1.0 + dot( normalize( I ), worldNormal ), mFresnelPower );",

      "gl_Position = projectionMatrix * mvPosition;",

      "}"

    ].join("\n"),

    fragmentShader: [

      "uniform samplerCube tCube;",
      "uniform float alpha;",

      "varying vec3 vReflect;",
      "varying vec3 vRefract[3];",
      "varying float vReflectionFactor;",

      "void main() {",

      "vec4 reflectedColor = textureCube( tCube, vec3( -vReflect.x, vReflect.yz ) );",
      "vec4 refractedColor = vec4( 1.0 );",
      
      // тут инвертируем значени для vRefractor[n].x, что бы куб не казался прозрачным
      // что бы отображалось то, что "отражается" на сфере со стороны камеры, а не то, что за кубом
      // можно поиграться со знаком для этой величины, чтобы стало понятно о чем речь
      "refractedColor.r = textureCube( tCube, vec3( vRefract[0].x, vRefract[0].yz ) ).r;",
      "refractedColor.g = textureCube( tCube, vec3( vRefract[1].x, vRefract[1].yz ) ).g;",
      "refractedColor.b = textureCube( tCube, vec3( vRefract[2].x, vRefract[2].yz ) ).b;",
      "refractedColor.a = alpha;", // тут устанавливаем значение прозрачности

      "gl_FragColor = mix( refractedColor, reflectedColor, clamp( vReflectionFactor, 0.0, 1.0 ) );",

      "}"

    ].join("\n")

  };
</script>