webgl_postprocessing_transition

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.js

import * as THREE from "three";
import TWEEN from "three/examples/jsm/libs/tween.module.js";
import { EffectComposer } from "three/examples/jsm/postprocessing/EffectComposer.js";
import { RenderTransitionPass } from "three/examples/jsm/postprocessing/RenderTransitionPass.js";
import { OutputPass } from "three/examples/jsm/postprocessing/OutputPass.js";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_postprocessing_transition",
  useLoaders: [],
  info: [
    [
      {
        tag: "a",
        link: "https://threejs.org",
        content: "three.js"
      },
      {
        tag: "text",
        content: "webgl scene transitions"
      },
      {
        tag: "text",
        content: "by"
      },
      {
        tag: "a",
        link: "https://twitter.com/fernandojsg",
        content: "fernandojsg"
      },
      {
        tag: "text",
        content: "-"
      },
      {
        tag: "a",
        link: "https://github.com/kile/three.js-demos",
        content: "github"
      }
    ]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let stats;
    let renderer, composer, renderTransitionPass;
    const textures = [];
    const clock = new THREE.Clock();
    const params = {
      sceneAnimate: true,
      transitionAnimate: true,
      transition: 0,
      useTexture: true,
      texture: 5,
      cycle: true,
      threshold: 0.1
    };
    const fxSceneA = new FXScene(
      new THREE.BoxGeometry(2, 2, 2),
      new THREE.Vector3(0, -0.4, 0),
      16777215
    );
    const fxSceneB = new FXScene(
      new THREE.IcosahedronGeometry(1, 1),
      new THREE.Vector3(0, 0.2, 0.1),
      0
    );
    init();
    function init() {
      initGUI();
      initTextures();
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(window.innerWidth, window.innerHeight);
      renderer.setAnimationLoop(animate);
      composer = new EffectComposer(renderer);
      stats = new Stats(renderer);
      renderTransitionPass = new RenderTransitionPass(
        fxSceneA.scene,
        fxSceneA.camera,
        fxSceneB.scene,
        fxSceneB.camera
      );
      renderTransitionPass.setTexture(textures[0]);
      composer.addPass(renderTransitionPass);
      const outputPass = new OutputPass();
      composer.addPass(outputPass);
      needToDispose(renderer, fxSceneA.scene, fxSceneB.scene, composer);
    }
    window.addEventListener("resize", onWindowResize);
    function onWindowResize() {
      fxSceneA.resize();
      fxSceneB.resize();
      renderer.setSize(window.innerWidth, window.innerHeight);
      composer.setSize(window.innerWidth, window.innerHeight);
    }
    new TWEEN.Tween(params).to({ transition: 1 }, 1500).onUpdate(function() {
      renderTransitionPass.setTransition(params.transition);
      if (params.cycle) {
        if (params.transition == 0 || params.transition == 1) {
          params.texture = (params.texture + 1) % textures.length;
          renderTransitionPass.setTexture(textures[params.texture]);
        }
      }
    }).repeat(Infinity).delay(2e3).yoyo(true).start();
    function animate() {
      if (params.transitionAnimate) TWEEN.update();
      const delta = clock.getDelta();
      fxSceneA.update(delta);
      fxSceneB.update(delta);
      render();
      stats.update();
    }
    function initTextures() {
      const loader = new THREE.TextureLoader();
      for (let i = 0; i < 6; i++) {
        textures[i] = loader.load("textures/transition/transition" + (i + 1) + ".png");
      }
    }
    function initGUI() {
      const gui = new GUI();
      gui.add(params, "sceneAnimate").name("Animate scene");
      gui.add(params, "transitionAnimate").name("Animate transition");
      gui.add(params, "transition", 0, 1, 0.01).onChange(function(value) {
        renderTransitionPass.setTransition(value);
      }).listen();
      gui.add(params, "useTexture").onChange(function(value) {
        renderTransitionPass.useTexture(value);
      });
      gui.add(params, "texture", {
        Perlin: 0,
        Squares: 1,
        Cells: 2,
        Distort: 3,
        Gradient: 4,
        Radial: 5
      }).onChange(function(value) {
        renderTransitionPass.setTexture(textures[value]);
      }).listen();
      gui.add(params, "cycle");
      gui.add(params, "threshold", 0, 1, 0.01).onChange(function(value) {
        renderTransitionPass.setTextureThreshold(value);
      });
    }
    function render() {
      if (params.transition === 0) {
        renderer.render(fxSceneB.scene, fxSceneB.camera);
      } else if (params.transition === 1) {
        renderer.render(fxSceneA.scene, fxSceneA.camera);
      } else {
        composer.render();
      }
    }
    function FXScene(geometry, rotationSpeed, backgroundColor) {
      const camera = new THREE.PerspectiveCamera(
        50,
        window.innerWidth / window.innerHeight,
        0.1,
        100
      );
      camera.position.z = 20;
      const scene = new THREE.Scene();
      scene.background = new THREE.Color(backgroundColor);
      scene.add(new THREE.AmbientLight(11184810, 3));
      const light = new THREE.DirectionalLight(16777215, 3);
      light.position.set(0, 1, 4);
      scene.add(light);
      this.rotationSpeed = rotationSpeed;
      const color = geometry.type === "BoxGeometry" ? 255 : 16711680;
      const material = new THREE.MeshPhongMaterial({ color, flatShading: true });
      const mesh = generateInstancedMesh(geometry, material, 500);
      scene.add(mesh);
      this.scene = scene;
      this.camera = camera;
      this.mesh = mesh;
      this.update = function(delta) {
        if (params.sceneAnimate) {
          mesh.rotation.x += this.rotationSpeed.x * delta;
          mesh.rotation.y += this.rotationSpeed.y * delta;
          mesh.rotation.z += this.rotationSpeed.z * delta;
        }
      };
      this.resize = function() {
        camera.aspect = window.innerWidth / window.innerHeight;
        camera.updateProjectionMatrix();
      };
    }
    function generateInstancedMesh(geometry, material, count) {
      const mesh = new THREE.InstancedMesh(geometry, material, count);
      const dummy = new THREE.Object3D();
      const color = new THREE.Color();
      for (let i = 0; i < count; i++) {
        dummy.position.x = Math.random() * 100 - 50;
        dummy.position.y = Math.random() * 60 - 30;
        dummy.position.z = Math.random() * 80 - 40;
        dummy.rotation.x = Math.random() * 2 * Math.PI;
        dummy.rotation.y = Math.random() * 2 * Math.PI;
        dummy.rotation.z = Math.random() * 2 * Math.PI;
        dummy.scale.x = Math.random() * 2 + 1;
        if (geometry.type === "BoxGeometry") {
          dummy.scale.y = Math.random() * 2 + 1;
          dummy.scale.z = Math.random() * 2 + 1;
        } else {
          dummy.scale.y = dummy.scale.x;
          dummy.scale.z = dummy.scale.x;
        }
        dummy.updateMatrix();
        mesh.setMatrixAt(i, dummy.matrix);
        mesh.setColorAt(i, color.setScalar(0.1 + 0.9 * Math.random()));
      }
      return mesh;
    }
  }
};
export {
  exampleInfo as default
};

typings.d.ts

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;