webgl_custom_attributes_points2
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 * as BufferGeometryUtils from "three/examples/jsm/utils/BufferGeometryUtils.js";
/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
name: "webgl_custom_attributes_points2",
useLoaders: [],
info: [
[
{
tag: "a",
link: "https://threejs.org",
content: "three.js"
},
{
tag: "text",
content: "- custom attributes example - particles - billboards"
}
]
],
init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
let renderer, scene, camera, stats;
let sphere, length1;
const WIDTH = window.innerWidth;
const HEIGHT = window.innerHeight;
init();
function init() {
camera = new THREE.PerspectiveCamera(45, WIDTH / HEIGHT, 1, 1e4);
camera.position.z = 300;
scene = new THREE.Scene();
const radius = 100, segments = 68, rings = 38;
let sphereGeometry = new THREE.SphereGeometry(radius, segments, rings);
let boxGeometry = new THREE.BoxGeometry(0.8 * radius, 0.8 * radius, 0.8 * radius, 10, 10, 10);
sphereGeometry.deleteAttribute("normal");
sphereGeometry.deleteAttribute("uv");
boxGeometry.deleteAttribute("normal");
boxGeometry.deleteAttribute("uv");
sphereGeometry = BufferGeometryUtils.mergeVertices(sphereGeometry);
boxGeometry = BufferGeometryUtils.mergeVertices(boxGeometry);
const combinedGeometry = BufferGeometryUtils.mergeGeometries([sphereGeometry, boxGeometry]);
const positionAttribute = combinedGeometry.getAttribute("position");
const colors = [];
const sizes = [];
const color = new THREE.Color();
const vertex = new THREE.Vector3();
length1 = sphereGeometry.getAttribute("position").count;
for (let i = 0, l = positionAttribute.count; i < l; i++) {
vertex.fromBufferAttribute(positionAttribute, i);
if (i < length1) {
color.setHSL(0.01 + 0.1 * (i / length1), 0.99, (vertex.y + radius) / (4 * radius));
} else {
color.setHSL(0.6, 0.75, 0.25 + vertex.y / (2 * radius));
}
color.toArray(colors, i * 3);
sizes[i] = i < length1 ? 10 : 40;
}
const geometry = new THREE.BufferGeometry();
geometry.setAttribute("position", positionAttribute);
geometry.setAttribute("size", new THREE.Float32BufferAttribute(sizes, 1));
geometry.setAttribute("ca", new THREE.Float32BufferAttribute(colors, 3));
const texture = new THREE.TextureLoader().load("textures/sprites/disc.png");
texture.wrapS = THREE.RepeatWrapping;
texture.wrapT = THREE.RepeatWrapping;
const material = new THREE.ShaderMaterial({
uniforms: {
color: { value: new THREE.Color(16777215) },
pointTexture: { value: texture }
},
vertexShader: `
attribute float size;
attribute vec3 ca;
varying vec3 vColor;
void main() {
vColor = ca;
vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );
gl_PointSize = size * ( 300.0 / -mvPosition.z );
gl_Position = projectionMatrix * mvPosition;
}
`,
fragmentShader: `
uniform vec3 color;
uniform sampler2D pointTexture;
varying vec3 vColor;
void main() {
vec4 color = vec4( color * vColor, 1.0 ) * texture2D( pointTexture, gl_PointCoord );
gl_FragColor = color;
}
`,
transparent: true
});
sphere = new THREE.Points(geometry, material);
scene.add(sphere);
renderer = new THREE.WebGLRenderer({ canvas });
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(WIDTH, HEIGHT);
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 sortPoints() {
const vector = new THREE.Vector3();
const matrix = new THREE.Matrix4();
matrix.multiplyMatrices(camera.projectionMatrix, camera.matrixWorldInverse);
matrix.multiply(sphere.matrixWorld);
const geometry = sphere.geometry;
let index = geometry.getIndex();
const positions = geometry.getAttribute("position").array;
const length = positions.length / 3;
if (index === null) {
const array = new Uint16Array(length);
for (let i = 0; i < length; i++) {
array[i] = i;
}
index = new THREE.BufferAttribute(array, 1);
geometry.setIndex(index);
}
const sortArray = [];
for (let i = 0; i < length; i++) {
vector.fromArray(positions, i * 3);
vector.applyMatrix4(matrix);
sortArray.push([vector.z, i]);
}
function numericalSort(a, b) {
return b[0] - a[0];
}
sortArray.sort(numericalSort);
const indices = index.array;
for (let i = 0; i < length; i++) {
indices[i] = sortArray[i][1];
}
geometry.index.needsUpdate = true;
}
function animate() {
render();
stats.update();
}
function render() {
const time = Date.now() * 5e-3;
sphere.rotation.y = 0.02 * time;
sphere.rotation.z = 0.02 * time;
const geometry = sphere.geometry;
const attributes = geometry.attributes;
for (let i = 0; i < attributes.size.array.length; i++) {
if (i < length1) {
attributes.size.array[i] = 16 + 12 * Math.sin(0.1 * i + time);
}
}
attributes.size.needsUpdate = true;
sortPoints();
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;