webgl_shadow_contact

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 { OrbitControls } from "three/examples/jsm/controls/OrbitControls.js";
import { HorizontalBlurShader } from "three/examples/jsm/shaders/HorizontalBlurShader.js";
import { VerticalBlurShader } from "three/examples/jsm/shaders/VerticalBlurShader.js";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_shadow_contact",
  useLoaders: [],
  info: [
    [
      {
        tag: "a",
        link: "https://threejs.org",
        content: "three.js"
      },
      {
        tag: "text",
        content: "webgl - contact shadows"
      }
    ]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let camera, scene, renderer, stats, gui;
    const meshes = [];
    const PLANE_WIDTH = 2.5;
    const PLANE_HEIGHT = 2.5;
    const CAMERA_HEIGHT = 0.3;
    const state = {
      shadow: {
        blur: 3.5,
        darkness: 1,
        opacity: 1
      },
      plane: {
        color: "#ffffff",
        opacity: 1
      },
      showWireframe: false
    };
    let shadowGroup, renderTarget, renderTargetBlur, shadowCamera, cameraHelper, depthMaterial, horizontalBlurMaterial, verticalBlurMaterial;
    let plane, blurPlane, fillPlane;
    init();
    function init() {
      camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 0.1, 100);
      camera.position.set(0.5, 1, 2);
      scene = new THREE.Scene();
      scene.background = new THREE.Color(16777215);
      stats = new Stats(renderer);
      window.addEventListener("resize", onWindowResize);
      const geometries = [
        new THREE.BoxGeometry(0.4, 0.4, 0.4),
        new THREE.IcosahedronGeometry(0.3),
        new THREE.TorusKnotGeometry(0.4, 0.05, 256, 24, 1, 3)
      ];
      const material = new THREE.MeshNormalMaterial();
      for (let i = 0, l = geometries.length; i < l; i++) {
        const angle = i / l * Math.PI * 2;
        const geometry = geometries[i];
        const mesh = new THREE.Mesh(geometry, material);
        mesh.position.y = 0.1;
        mesh.position.x = Math.cos(angle) / 2;
        mesh.position.z = Math.sin(angle) / 2;
        scene.add(mesh);
        meshes.push(mesh);
      }
      shadowGroup = new THREE.Group();
      shadowGroup.position.y = -0.3;
      scene.add(shadowGroup);
      renderTarget = new THREE.WebGLRenderTarget(512, 512);
      renderTarget.texture.generateMipmaps = false;
      renderTargetBlur = new THREE.WebGLRenderTarget(512, 512);
      renderTargetBlur.texture.generateMipmaps = false;
      const planeGeometry = new THREE.PlaneGeometry(PLANE_WIDTH, PLANE_HEIGHT).rotateX(Math.PI / 2);
      const planeMaterial = new THREE.MeshBasicMaterial({
        map: renderTarget.texture,
        opacity: state.shadow.opacity,
        transparent: true,
        depthWrite: false
      });
      plane = new THREE.Mesh(planeGeometry, planeMaterial);
      plane.renderOrder = 1;
      shadowGroup.add(plane);
      plane.scale.y = -1;
      blurPlane = new THREE.Mesh(planeGeometry);
      blurPlane.visible = false;
      shadowGroup.add(blurPlane);
      const fillPlaneMaterial = new THREE.MeshBasicMaterial({
        color: state.plane.color,
        opacity: state.plane.opacity,
        transparent: true,
        depthWrite: false
      });
      fillPlane = new THREE.Mesh(planeGeometry, fillPlaneMaterial);
      fillPlane.rotateX(Math.PI);
      shadowGroup.add(fillPlane);
      shadowCamera = new THREE.OrthographicCamera(
        -2.5 / 2,
        PLANE_WIDTH / 2,
        PLANE_HEIGHT / 2,
        -2.5 / 2,
        0,
        CAMERA_HEIGHT
      );
      shadowCamera.rotation.x = Math.PI / 2;
      shadowGroup.add(shadowCamera);
      cameraHelper = new THREE.CameraHelper(shadowCamera);
      depthMaterial = new THREE.MeshDepthMaterial();
      depthMaterial.userData.darkness = { value: state.shadow.darkness };
      depthMaterial.onBeforeCompile = function(shader) {
        shader.uniforms.darkness = depthMaterial.userData.darkness;
        shader.fragmentShader = /* glsl */
        `
						uniform float darkness;
						${shader.fragmentShader.replace(
          "gl_FragColor = vec4( vec3( 1.0 - fragCoordZ ), opacity );",
          "gl_FragColor = vec4( vec3( 0.0 ), ( 1.0 - fragCoordZ ) * darkness );"
        )}
					`;
      };
      depthMaterial.depthTest = false;
      depthMaterial.depthWrite = false;
      horizontalBlurMaterial = new THREE.ShaderMaterial(HorizontalBlurShader);
      horizontalBlurMaterial.depthTest = false;
      verticalBlurMaterial = new THREE.ShaderMaterial(VerticalBlurShader);
      verticalBlurMaterial.depthTest = false;
      gui = new GUI();
      const shadowFolder = gui.addFolder("shadow");
      shadowFolder.open();
      const planeFolder = gui.addFolder("plane");
      planeFolder.open();
      shadowFolder.add(state.shadow, "blur", 0, 15, 0.1);
      shadowFolder.add(state.shadow, "darkness", 1, 5, 0.1).onChange(function() {
        depthMaterial.userData.darkness.value = state.shadow.darkness;
      });
      shadowFolder.add(state.shadow, "opacity", 0, 1, 0.01).onChange(function() {
        plane.material.opacity = state.shadow.opacity;
      });
      planeFolder.addColor(state.plane, "color").onChange(function() {
        fillPlane.material.color = new THREE.Color(state.plane.color);
      });
      planeFolder.add(state.plane, "opacity", 0, 1, 0.01).onChange(function() {
        fillPlane.material.opacity = state.plane.opacity;
      });
      gui.add(state, "showWireframe").onChange(function() {
        if (state.showWireframe) {
          scene.add(cameraHelper);
        } else {
          scene.remove(cameraHelper);
        }
      });
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(window.innerWidth, window.innerHeight);
      renderer.setAnimationLoop(animate);
      const controls = new OrbitControls(camera, renderer.domElement);
      needToDispose(renderer, scene, controls);
    }
    function onWindowResize() {
      camera.aspect = window.innerWidth / window.innerHeight;
      camera.updateProjectionMatrix();
      renderer.setSize(window.innerWidth, window.innerHeight);
    }
    function blurShadow(amount) {
      blurPlane.visible = true;
      blurPlane.material = horizontalBlurMaterial;
      blurPlane.material.uniforms.tDiffuse.value = renderTarget.texture;
      horizontalBlurMaterial.uniforms.h.value = amount * 1 / 256;
      renderer.setRenderTarget(renderTargetBlur);
      renderer.render(blurPlane, shadowCamera);
      blurPlane.material = verticalBlurMaterial;
      blurPlane.material.uniforms.tDiffuse.value = renderTargetBlur.texture;
      verticalBlurMaterial.uniforms.v.value = amount * 1 / 256;
      renderer.setRenderTarget(renderTarget);
      renderer.render(blurPlane, shadowCamera);
      blurPlane.visible = false;
    }
    function animate() {
      meshes.forEach((mesh) => {
        mesh.rotation.x += 0.01;
        mesh.rotation.y += 0.02;
      });
      const initialBackground = scene.background;
      scene.background = null;
      cameraHelper.visible = false;
      scene.overrideMaterial = depthMaterial;
      const initialClearAlpha = renderer.getClearAlpha();
      renderer.setClearAlpha(0);
      renderer.setRenderTarget(renderTarget);
      renderer.render(scene, shadowCamera);
      scene.overrideMaterial = null;
      cameraHelper.visible = true;
      blurShadow(state.shadow.blur);
      blurShadow(state.shadow.blur * 0.4);
      renderer.setRenderTarget(null);
      renderer.setClearAlpha(initialClearAlpha);
      scene.background = initialBackground;
      renderer.render(scene, camera);
      stats.update();
    }
  }
};
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;