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webgl_custom_attributes_lines

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。

js
import * as THREE from "three";
import { FontLoader } from "three/examples/jsm/loaders/FontLoader.js";
import { TextGeometry } from "three/examples/jsm/geometries/TextGeometry.js";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_custom_attributes_lines",
  useLoaders: [FontLoader],
  info: [
    [
      {
        tag: "a",
        link: "https://threejs.org",
        content: "three.js"
      },
      {
        tag: "text",
        content: "- custom attributes example"
      }
    ]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let renderer, scene, camera, stats;
    let line, uniforms;
    const loader = new FontLoader();
    loader.load("fonts/helvetiker_bold.typeface.json", function(font) {
      init(font);
    });
    function init(font) {
      camera = new THREE.PerspectiveCamera(30, window.innerWidth / window.innerHeight, 1, 1e4);
      camera.position.z = 400;
      scene = new THREE.Scene();
      scene.background = new THREE.Color(328965);
      uniforms = {
        amplitude: { value: 5 },
        opacity: { value: 0.3 },
        color: { value: new THREE.Color(16777215) }
      };
      const shaderMaterial = new THREE.ShaderMaterial({
        uniforms,
        vertexShader: `

			uniform float amplitude;

			attribute vec3 displacement;
			attribute vec3 customColor;

			varying vec3 vColor;

			void main() {

				vec3 newPosition = position + amplitude * displacement;

				vColor = customColor;

				gl_Position = projectionMatrix * modelViewMatrix * vec4( newPosition, 1.0 );

			}

		`,
        fragmentShader: `

			uniform vec3 color;
			uniform float opacity;

			varying vec3 vColor;

			void main() {

				gl_FragColor = vec4( vColor * color, opacity );

			}

		`,
        blending: THREE.AdditiveBlending,
        depthTest: false,
        transparent: true
      });
      const geometry = new TextGeometry("three.js", {
        font,
        size: 50,
        depth: 15,
        curveSegments: 10,
        bevelThickness: 5,
        bevelSize: 1.5,
        bevelEnabled: true,
        bevelSegments: 10
      });
      geometry.center();
      const count = geometry.attributes.position.count;
      const displacement = new THREE.Float32BufferAttribute(count * 3, 3);
      geometry.setAttribute("displacement", displacement);
      const customColor = new THREE.Float32BufferAttribute(count * 3, 3);
      geometry.setAttribute("customColor", customColor);
      const color = new THREE.Color(16777215);
      for (let i = 0, l = customColor.count; i < l; i++) {
        color.setHSL(i / l, 0.5, 0.5);
        color.toArray(customColor.array, i * customColor.itemSize);
      }
      line = new THREE.Line(geometry, shaderMaterial);
      line.rotation.x = 0.2;
      scene.add(line);
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(window.innerWidth, window.innerHeight);
      renderer.setAnimationLoop(animate);
      stats = new Stats(renderer);
      window.addEventListener("resize", onWindowResize);
      needToDispose(renderer, scene);
    }
    function onWindowResize() {
      camera.aspect = window.innerWidth / window.innerHeight;
      camera.updateProjectionMatrix();
      renderer.setSize(window.innerWidth, window.innerHeight);
    }
    function animate() {
      render();
      stats.update();
    }
    function render() {
      const time = Date.now() * 1e-3;
      line.rotation.y = 0.25 * time;
      uniforms.amplitude.value = Math.sin(0.5 * time);
      uniforms.color.value.offsetHSL(5e-4, 0, 0);
      const attributes = line.geometry.attributes;
      const array = attributes.displacement.array;
      for (let i = 0, l = array.length; i < l; i += 3) {
        array[i] += 0.3 * (0.5 - Math.random());
        array[i + 1] += 0.3 * (0.5 - Math.random());
        array[i + 2] += 0.3 * (0.5 - Math.random());
      }
      attributes.displacement.needsUpdate = true;
      renderer.render(scene, camera);
    }
  }
};
export {
  exampleInfo as default
};
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;