webgl_instancing_performance

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 * as BufferGeometryUtils from "three/examples/jsm/utils/BufferGeometryUtils.js";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_instancing_performance",
  useLoaders: [],
  info: [
    [
      {
        tag: "a",
        link: "https://threejs.org",
        content: "three.js"
      },
      {
        tag: "text",
        content: "webgl - instancing - performance"
      }
    ]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let stats, gui;
    let camera, controls, scene, renderer, material;
    const Method = {
      INSTANCED: "INSTANCED",
      MERGED: "MERGED",
      NAIVE: "NAIVE"
    };
    const api = {
      method: Method.INSTANCED,
      count: 1e3,
      drawCalls: "-",
      memory: "-"
    };
    init();
    initMesh();
    function clean() {
      const meshes = [];
      scene.traverse(function(object) {
        if (object.isMesh) meshes.push(object);
      });
      for (let i = 0; i < meshes.length; i++) {
        const mesh = meshes[i];
        mesh.material.dispose();
        mesh.geometry.dispose();
        scene.remove(mesh);
      }
    }
    const randomizeMatrix = function() {
      const position = new THREE.Vector3();
      const quaternion = new THREE.Quaternion();
      const scale = new THREE.Vector3();
      return function(matrix) {
        position.x = Math.random() * 40 - 20;
        position.y = Math.random() * 40 - 20;
        position.z = Math.random() * 40 - 20;
        quaternion.random();
        scale.x = scale.y = scale.z = Math.random() * 1;
        matrix.compose(position, quaternion, scale);
      };
    }();
    function initMesh() {
      clean();
      new THREE.BufferGeometryLoader().setPath("models/json/").load("suzanne_buffergeometry.json", function(geometry) {
        material = new THREE.MeshNormalMaterial();
        geometry.computeVertexNormals();
        console.time(api.method + " (build)");
        switch (api.method) {
          case Method.INSTANCED:
            makeInstanced(geometry);
            break;
          case Method.MERGED:
            makeMerged(geometry);
            break;
          case Method.NAIVE:
            makeNaive(geometry);
            break;
        }
        console.timeEnd(api.method + " (build)");
      });
    }
    function makeInstanced(geometry) {
      const matrix = new THREE.Matrix4();
      const mesh = new THREE.InstancedMesh(geometry, material, api.count);
      for (let i = 0; i < api.count; i++) {
        randomizeMatrix(matrix);
        mesh.setMatrixAt(i, matrix);
      }
      scene.add(mesh);
      const geometryByteLength = getGeometryByteLength(geometry);
      api.drawCalls = "1";
      api.memory = formatBytes(api.count * 16 + geometryByteLength, 2);
    }
    function makeMerged(geometry) {
      const geometries = [];
      const matrix = new THREE.Matrix4();
      for (let i = 0; i < api.count; i++) {
        randomizeMatrix(matrix);
        const instanceGeometry = geometry.clone();
        instanceGeometry.applyMatrix4(matrix);
        geometries.push(instanceGeometry);
      }
      const mergedGeometry = BufferGeometryUtils.mergeGeometries(geometries);
      scene.add(new THREE.Mesh(mergedGeometry, material));
      api.drawCalls = "1";
      api.memory = formatBytes(getGeometryByteLength(mergedGeometry), 2);
    }
    function makeNaive(geometry) {
      const matrix = new THREE.Matrix4();
      for (let i = 0; i < api.count; i++) {
        randomizeMatrix(matrix);
        const mesh = new THREE.Mesh(geometry, material);
        mesh.applyMatrix4(matrix);
        scene.add(mesh);
      }
      const geometryByteLength = getGeometryByteLength(geometry);
      api.drawCalls = `${api.count}`;
      api.memory = formatBytes(api.count * 16 + geometryByteLength, 2);
    }
    function init() {
      const width = window.innerWidth;
      const height = window.innerHeight;
      camera = new THREE.PerspectiveCamera(70, width / height, 1, 100);
      camera.position.z = 30;
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(width, height);
      renderer.setAnimationLoop(animate);
      scene = new THREE.Scene();
      scene.background = new THREE.Color(16777215);
      controls = new OrbitControls(camera, renderer.domElement);
      controls.autoRotate = true;
      stats = new Stats(renderer);
      gui = new GUI();
      gui.add(api, "method", Method);
      gui.add(api, "count", 1, 1e4).step(1);
      gui.add(
        {
          apply() {
            initMesh();
          }
        },
        "apply"
      );
      const perfFolder = gui.addFolder("Performance");
      const c1 = perfFolder.add(api, "drawCalls").name("GPU draw calls").disable(true).listen();
      const c2 = perfFolder.add(api, "memory").name("GPU memory").disable(true).listen();
      perfFolder.open();
      window.addEventListener("resize", onWindowResize);
      Object.assign(window, { scene });
      needToDispose(renderer, scene, controls, {
        dispose() {
          c1.listen(false);
          c2.listen(false);
        }
      });
    }
    function onWindowResize() {
      const width = window.innerWidth;
      const height = window.innerHeight;
      camera.aspect = width / height;
      camera.updateProjectionMatrix();
      renderer.setSize(width, height);
    }
    function animate() {
      controls.update();
      renderer.render(scene, camera);
      stats.update();
    }
    function getGeometryByteLength(geometry) {
      let total = 0;
      if (geometry.index) total += geometry.index.array.byteLength;
      for (const name in geometry.attributes) {
        total += geometry.attributes[name].array.byteLength;
      }
      return total;
    }
    function formatBytes(bytes, decimals) {
      if (bytes === 0) return "0 bytes";
      const k = 1024;
      const dm = decimals;
      const sizes = ["bytes", "KB", "MB"];
      const i = Math.floor(Math.log(bytes) / Math.log(k));
      return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + " " + sizes[i];
    }
  }
};
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;