webgl_geometry_colors_lookuptable

对应 three.js 示例地址。

仅需关注 init 函数的内容，其他部分都是示例小程序所使用的描述配置。

example.jstypings.d.ts

import * as THREE from "three";
import { OrbitControls } from "three/examples/jsm/controls/OrbitControls.js";
import { Lut } from "three/examples/jsm/math/Lut.js";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_geometry_colors_lookuptable",
  useLoaders: [],
  info: [
    [
      { tag: "a", link: "https://threejs.org", content: "three.js" },
      { tag: "text", content: "webgl - lookup table" }
    ],
    [{ tag: "text", content: "vertex color values from a range of data values" }]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let perpCamera, orthoCamera, renderer, lut;
    let mesh, sprite;
    let scene, uiScene;
    let params;
    init();
    function init() {
      scene = new THREE.Scene();
      scene.background = new THREE.Color(16777215);
      uiScene = new THREE.Scene();
      lut = new Lut();
      const width = window.innerWidth;
      const height = window.innerHeight;
      perpCamera = new THREE.PerspectiveCamera(60, width / height, 1, 100);
      perpCamera.position.set(0, 0, 10);
      scene.add(perpCamera);
      orthoCamera = new THREE.OrthographicCamera(-1, 1, 1, -1, 1, 2);
      orthoCamera.position.set(0.5, 0, 1);
      sprite = new THREE.Sprite(
        new THREE.SpriteMaterial({
          map: new THREE.CanvasTexture(lut.createCanvas())
        })
      );
      sprite.material.map.colorSpace = THREE.SRGBColorSpace;
      sprite.scale.x = 0.125;
      uiScene.add(sprite);
      mesh = new THREE.Mesh(
        void 0,
        new THREE.MeshLambertMaterial({
          side: THREE.DoubleSide,
          color: 16119285,
          vertexColors: true
        })
      );
      scene.add(mesh);
      params = {
        colorMap: "rainbow"
      };
      loadModel();
      const pointLight = new THREE.PointLight(16777215, 3, 0, 0);
      perpCamera.add(pointLight);
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.autoClear = false;
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(width, height);
      window.addEventListener("resize", onWindowResize);
      const controls = new OrbitControls(perpCamera, renderer.domElement);
      controls.addEventListener("change", render);
      const gui = new GUI();
      gui.add(params, "colorMap", ["rainbow", "cooltowarm", "blackbody", "grayscale"]).onChange(function() {
        updateColors();
        render();
      });
      needToDispose(renderer, scene, controls);
    }
    function onWindowResize() {
      const width = window.innerWidth;
      const height = window.innerHeight;
      perpCamera.aspect = width / height;
      perpCamera.updateProjectionMatrix();
      renderer.setSize(width, height);
      render();
    }
    function render() {
      renderer.clear();
      renderer.render(scene, perpCamera);
      renderer.render(uiScene, orthoCamera);
    }
    function loadModel() {
      const loader = new THREE.BufferGeometryLoader();
      loader.load("models/json/pressure.json", function(geometry) {
        geometry.center();
        geometry.computeVertexNormals();
        const colors = [];
        for (let i = 0, n = geometry.attributes.position.count; i < n; ++i) {
          colors.push(1, 1, 1);
        }
        geometry.setAttribute("color", new THREE.Float32BufferAttribute(colors, 3));
        mesh.geometry = geometry;
        updateColors();
        render();
      });
    }
    function updateColors() {
      lut.setColorMap(params.colorMap);
      lut.setMax(2e3);
      lut.setMin(0);
      const geometry = mesh.geometry;
      const pressures = geometry.attributes.pressure;
      const colors = geometry.attributes.color;
      const color = new THREE.Color();
      for (let i = 0; i < pressures.array.length; i++) {
        const colorValue = pressures.array[i];
        color.copy(lut.getColor(colorValue)).convertSRGBToLinear();
        colors.setXYZ(i, color.r, color.g, color.b);
      }
      colors.needsUpdate = true;
      const map = sprite.material.map;
      lut.updateCanvas(map.image);
      map.needsUpdate = true;
    }
  }
};
export {
  exampleInfo as default
};

import { Loader, TypedArray } from 'three';
/**
 * 官网示例的多端使用封装把版本
 * */
export interface OfficialExampleInfo extends MiniProgramMeta {
  /*** 示例名称（保持和官网一致）*/
  name: string;
  /** main */
  init: (context: LoadContext) => void;
}

export interface LoadContext {
  //为了减少官方代码的改动，实际上等同于 canvas
  window: EventTarget & { innerWidth: number; innerHeight: number; devicePixelRatio: number };
  /** HTMLCanvasElement */
  canvas: any;
  /** https://www.npmjs.com/package/lil-gui */
  GUI: any;
  /**
   * https://www.npmjs.com/package/stats.js
   * 也可以使用其他受支持的版本
   * */
  Stats: any;
  /** 收集需要 dispose 的对象（官方示例没有处理这部分）*/
  needToDispose: (...objs: any[]) => void | ((fromFn: () => any[]) => void);

  /**基于 raq 的通用封装 */
  useFrame(animateFunc: (/** ms */ delta: number) => void): { cancel: () => void };

  /** 显示加载模态框 */
  requestLoading(text?: string): Promise<void>;

  /** 隐藏加载模态框*/
  cancelLoading(): void;

  /** 保存文件的通用封装*/
  saveFile(
    fileName: string,
    data: ArrayBuffer | TypedArray | DataView | string
  ): Promise<string | null>;

  /** 示例使用 DracoDecoder 时的资源路径 */
  DecoderPath: {
    GLTF: string;
    STANDARD: string;
  };

  /** 为资源路径拼上 CDN 前缀 */
  withCDNPrefix(path: string): string;

  /**
   * 在小程序中应使用 import { VideoTexture } from '@minisheep/three-platform-adapter/override/jsm/textures/VideoTexture.js';
   * 正常情况（web） 可直接使用 THREE.VideoTexture
   * */
  getVideoTexture(videoOptions: VideoOptions): Promise<[{ isVideoTexture: true }, video: any]>;

  /**
   * 在小程序中应使用 import { CameraTexture } from '@minisheep/three-platform-adapter/override/jsm/textures/CameraTexture.js';
   * 正常情况（web） 可参考示例 webgl_materials_video_webcam
   * */
  getCameraTexture(): { isVideoTexture: true };

  /** 用于动态修改 info 中的占位符*/
  bindInfoText(template: `$${string}$`, initValue?: string): { value: string };

  /** 分屏控件对应的事件回调 */
  onSlideStart(handle: () => void): void;
  /** 分屏控件对应的事件回调 */
  onSlideEnd(handle: () => void): void;
  /** 分屏控件对应的事件回调 */
  onSlideChange(handle: (offset: number, boxSize: number) => void): void;
}

export type VideoOptions = {
  src: string;
  /** 相当于 HTMLVideoElement 的 naturalWidth (小程序中获取不到)*/
  width: number;
  /** 相当于 HTMLVideoElement 的 naturalHeight (小程序中获取不到)*/
  height: number;
  loop?: boolean;
  autoplay?: boolean;
  muted?: boolean;
};

/** 示例小程序中使用的一些配置 */
export interface MiniProgramMeta {
  /** 用于统计加载相关信息 */
  useLoaders: Loader[];
  /** 通用 info */
  info: TagItem[][];
  /** 特殊 info */
  infoPanel?: {
    left?: [string, string][];
    right?: [string, string][];
  };
  /** 分屏控件配置 */
  needSlider?: {
    /** 方向 */
    direction?: 'horizontal' | 'vertical';
    /** 初始偏移 0-100 */
    initPosition?: number;
  };
  /** 操作摇杆控件 */
  needArrowControls?: boolean;
  /** 默认需要的画布类型 */
  canvasType?: '2d' | 'webgl' | 'webgl2';
  /** 为保持效果一致所需要的画布样式 */
  canvasStyle?: {
    bgColor?: string;
    width?: number | string;
    height?: number | string;
  };
  /** 部分示例需要在加载前进行一些提示 */
  initAfterConfirm?: {
    /**
     * 提示类型
     * @default 'default'
     * */
    type?: 'warning' | 'default';
    text: string[];
  };
}

export interface BaseTag<T extends string> {
  tag: T;
  content: string;
}

export interface ATag extends BaseTag<'a'> {
  link: string;
}

export type TextTag = BaseTag<'text'>;

export type TagItem = TextTag | ATag;

webgl_geometry_colors_lookuptable ​

webgl_geometry_colors_lookuptable