webgl_buffergeometry_attributes_integer

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";

/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
  name: "webgl_buffergeometry_attributes_integer",
  useLoaders: [],
  info: [
    [
      {
        tag: "a",
        link: "https://threejs.org",
        content: "three.js"
      },
      {
        tag: "text",
        content: "WebGL 2 - buffergeometry - integer attributes"
      }
    ]
  ],
  init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
    let camera, scene, renderer, mesh;
    init();
    function init() {
      camera = new THREE.PerspectiveCamera(27, window.innerWidth / window.innerHeight, 1, 3500);
      camera.position.z = 2500;
      scene = new THREE.Scene();
      scene.background = new THREE.Color(328965);
      scene.fog = new THREE.Fog(328965, 2e3, 3500);
      const triangles = 1e4;
      const geometry = new THREE.BufferGeometry();
      const positions = [];
      const uvs = [];
      const textureIndices = [];
      const n = 800, n2 = n / 2;
      const d = 50, d2 = d / 2;
      for (let i = 0; i < triangles; i++) {
        const x = Math.random() * n - n2;
        const y = Math.random() * n - n2;
        const z = Math.random() * n - n2;
        const ax = x + Math.random() * d - d2;
        const ay = y + Math.random() * d - d2;
        const az = z + Math.random() * d - d2;
        const bx = x + Math.random() * d - d2;
        const by = y + Math.random() * d - d2;
        const bz = z + Math.random() * d - d2;
        const cx = x + Math.random() * d - d2;
        const cy = y + Math.random() * d - d2;
        const cz = z + Math.random() * d - d2;
        positions.push(ax, ay, az);
        positions.push(bx, by, bz);
        positions.push(cx, cy, cz);
        uvs.push(0, 0);
        uvs.push(0.5, 1);
        uvs.push(1, 0);
        const t = i % 3;
        textureIndices.push(t, t, t);
      }
      geometry.setAttribute("position", new THREE.Float32BufferAttribute(positions, 3));
      geometry.setAttribute("uv", new THREE.Float32BufferAttribute(uvs, 2));
      geometry.setAttribute("textureIndex", new THREE.Int16BufferAttribute(textureIndices, 1));
      geometry.attributes.textureIndex.gpuType = THREE.IntType;
      geometry.computeBoundingSphere();
      const loader = new THREE.TextureLoader();
      const map1 = loader.load("textures/crate.gif");
      const map2 = loader.load("textures/floors/FloorsCheckerboard_S_Diffuse.jpg");
      const map3 = loader.load("textures/terrain/grasslight-big.jpg");
      const material = new THREE.ShaderMaterial({
        uniforms: {
          uTextures: {
            value: [map1, map2, map3]
          }
        },
        vertexShader: `
			in int textureIndex;
			flat out int vIndex; // "flat" indicates that the value will not be interpolated (required for integer attributes)
			out vec2 vUv;
			void main()	{
				vIndex = textureIndex;
				vUv = uv;
				gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
			}
		`,
        fragmentShader: `
			flat in int vIndex;
			in vec2 vUv;
			uniform sampler2D uTextures[ 3 ];
			out vec4 outColor;
			void main()	{
				if ( vIndex == 0 ) outColor = texture( uTextures[ 0 ], vUv );
				else if ( vIndex == 1 ) outColor = texture( uTextures[ 1 ], vUv );
				else if ( vIndex == 2 ) outColor = texture( uTextures[ 2 ], vUv );
			}
		`,
        side: THREE.DoubleSide,
        glslVersion: THREE.GLSL3
      });
      mesh = new THREE.Mesh(geometry, material);
      scene.add(mesh);
      renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(window.innerWidth, window.innerHeight);
      renderer.setAnimationLoop(animate);
      needToDispose(renderer, scene);
    }
    function animate() {
      const time = Date.now() * 1e-3;
      mesh.rotation.x = time * 0.25;
      mesh.rotation.y = time * 0.5;
      renderer.render(scene, camera);
    }
  }
};
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_buffergeometry_attributes_integer ​

webgl_buffergeometry_attributes_integer