bytev-charts/lib/plugin/three.js/examples/js/objects/ShadowMesh.js

基于echarts和JavaScript及ES6封装的一个可以直接调用的图表组件库，内置主题设计，简单快捷，且支持用户自定义配置； npm 安装方式: npm install bytev-charts 若启动提示还需额外install插件,则运行 npm install @babel/runtime-corejs2 即可;

import _Object$create from "@babel/runtime-corejs2/core-js/object/create";
console.warn("THREE.ShadowMesh: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/#manual/en/introduction/Installation.");
/**
 * A shadow Mesh that follows a shadow-casting Mesh in the scene, but is confined to a single plane.
 */

THREE.ShadowMesh = function (mesh) {
  var shadowMaterial = new THREE.MeshBasicMaterial({
    color: 0x000000,
    transparent: true,
    opacity: 0.6,
    depthWrite: false
  });
  THREE.Mesh.call(this, mesh.geometry, shadowMaterial);
  this.meshMatrix = mesh.matrixWorld;
  this.frustumCulled = false;
  this.matrixAutoUpdate = false;
};

THREE.ShadowMesh.prototype = _Object$create(THREE.Mesh.prototype);
THREE.ShadowMesh.prototype.constructor = THREE.ShadowMesh;

THREE.ShadowMesh.prototype.update = function () {
  var shadowMatrix = new THREE.Matrix4();
  return function (plane, lightPosition4D) {
    // based on https://www.opengl.org/archives/resources/features/StencilTalk/tsld021.htm
    var dot = plane.normal.x * lightPosition4D.x + plane.normal.y * lightPosition4D.y + plane.normal.z * lightPosition4D.z + -plane.constant * lightPosition4D.w;
    var sme = shadowMatrix.elements;
    sme[0] = dot - lightPosition4D.x * plane.normal.x;
    sme[4] = -lightPosition4D.x * plane.normal.y;
    sme[8] = -lightPosition4D.x * plane.normal.z;
    sme[12] = -lightPosition4D.x * -plane.constant;
    sme[1] = -lightPosition4D.y * plane.normal.x;
    sme[5] = dot - lightPosition4D.y * plane.normal.y;
    sme[9] = -lightPosition4D.y * plane.normal.z;
    sme[13] = -lightPosition4D.y * -plane.constant;
    sme[2] = -lightPosition4D.z * plane.normal.x;
    sme[6] = -lightPosition4D.z * plane.normal.y;
    sme[10] = dot - lightPosition4D.z * plane.normal.z;
    sme[14] = -lightPosition4D.z * -plane.constant;
    sme[3] = -lightPosition4D.w * plane.normal.x;
    sme[7] = -lightPosition4D.w * plane.normal.y;
    sme[11] = -lightPosition4D.w * plane.normal.z;
    sme[15] = dot - lightPosition4D.w * -plane.constant;
    this.matrix.multiplyMatrices(shadowMatrix, this.meshMatrix);
  };
}();