webgl_lines_fat_raycasting
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 { OrbitControls } from "three/examples/jsm/controls/OrbitControls.js";
import { LineMaterial } from "three/examples/jsm/lines/LineMaterial.js";
import { LineSegments2 } from "three/examples/jsm/lines/LineSegments2.js";
import { LineSegmentsGeometry } from "three/examples/jsm/lines/LineSegmentsGeometry.js";
import { Line2 } from "three/examples/jsm/lines/Line2.js";
import { LineGeometry } from "three/examples/jsm/lines/LineGeometry.js";
/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
name: "webgl_lines_fat_raycasting",
useLoaders: [],
info: [
[
{
tag: "a",
link: "https://threejs.org",
content: "three.js"
},
{
tag: "text",
content: "- fat lines raycasting"
}
]
],
init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
let line, thresholdLine, segments, thresholdSegments;
let renderer, scene, camera, controls;
let sphereInter, sphereOnLine;
let stats;
let gui;
let clock;
const color = new THREE.Color();
const pointer = new THREE.Vector2(Infinity, Infinity);
const raycaster = new THREE.Raycaster();
raycaster.params.Line2 = {};
raycaster.params.Line2.threshold = 0;
const matLine = new LineMaterial({
color: 16777215,
linewidth: 1,
// in world units with size attenuation, pixels otherwise
worldUnits: true,
vertexColors: true,
alphaToCoverage: true
});
const matThresholdLine = new LineMaterial({
color: 16777215,
linewidth: matLine.linewidth,
// in world units with size attenuation, pixels otherwise
worldUnits: true,
// vertexColors: true,
transparent: true,
opacity: 0.2,
depthTest: false,
visible: false
});
const params = {
"line type": 0,
"world units": matLine.worldUnits,
"visualize threshold": matThresholdLine.visible,
width: matLine.linewidth,
alphaToCoverage: matLine.alphaToCoverage,
threshold: raycaster.params.Line2.threshold,
translation: raycaster.params.Line2.threshold,
animate: true
};
init();
function init() {
clock = new THREE.Clock();
renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true, canvas });
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColor(0, 0);
renderer.setAnimationLoop(animate);
scene = new THREE.Scene();
camera = new THREE.PerspectiveCamera(40, window.innerWidth / window.innerHeight, 1, 1e3);
camera.position.set(-40, 0, 60);
controls = new OrbitControls(camera, renderer.domElement);
controls.minDistance = 10;
controls.maxDistance = 500;
const sphereGeometry = new THREE.SphereGeometry(0.25, 8, 4);
const sphereInterMaterial = new THREE.MeshBasicMaterial({
color: 16711680,
depthTest: false
});
const sphereOnLineMaterial = new THREE.MeshBasicMaterial({
color: 65280,
depthTest: false
});
sphereInter = new THREE.Mesh(sphereGeometry, sphereInterMaterial);
sphereOnLine = new THREE.Mesh(sphereGeometry, sphereOnLineMaterial);
sphereInter.visible = false;
sphereOnLine.visible = false;
sphereInter.renderOrder = 10;
sphereOnLine.renderOrder = 10;
scene.add(sphereInter);
scene.add(sphereOnLine);
const positions = [];
const colors = [];
const points = [];
for (let i = -50; i < 50; i++) {
const t = i / 3;
points.push(new THREE.Vector3(t * Math.sin(2 * t), t, t * Math.cos(2 * t)));
}
const spline = new THREE.CatmullRomCurve3(points);
const divisions = Math.round(3 * points.length);
const point = new THREE.Vector3();
const color2 = new THREE.Color();
for (let i = 0, l = divisions; i < l; i++) {
const t = i / l;
spline.getPoint(t, point);
positions.push(point.x, point.y, point.z);
color2.setHSL(t, 1, 0.5, THREE.SRGBColorSpace);
colors.push(color2.r, color2.g, color2.b);
}
const lineGeometry = new LineGeometry();
lineGeometry.setPositions(positions);
lineGeometry.setColors(colors);
const segmentsGeometry = new LineSegmentsGeometry();
segmentsGeometry.setPositions(positions);
segmentsGeometry.setColors(colors);
segments = new LineSegments2(segmentsGeometry, matLine);
segments.computeLineDistances();
segments.scale.set(1, 1, 1);
scene.add(segments);
segments.visible = false;
thresholdSegments = new LineSegments2(segmentsGeometry, matThresholdLine);
thresholdSegments.computeLineDistances();
thresholdSegments.scale.set(1, 1, 1);
scene.add(thresholdSegments);
thresholdSegments.visible = false;
line = new Line2(lineGeometry, matLine);
line.computeLineDistances();
line.scale.set(1, 1, 1);
scene.add(line);
thresholdLine = new Line2(lineGeometry, matThresholdLine);
thresholdLine.computeLineDistances();
thresholdLine.scale.set(1, 1, 1);
scene.add(thresholdLine);
const geo = new THREE.BufferGeometry();
geo.setAttribute("position", new THREE.Float32BufferAttribute(positions, 3));
geo.setAttribute("color", new THREE.Float32BufferAttribute(colors, 3));
canvas.addEventListener("pointermove", onPointerMove);
window.addEventListener("resize", onWindowResize);
onWindowResize();
stats = new Stats(renderer);
initGui();
needToDispose(renderer, scene);
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
function onPointerMove(event) {
pointer.x = event.clientX / window.innerWidth * 2 - 1;
pointer.y = -(event.clientY / window.innerHeight) * 2 + 1;
}
function animate() {
const delta = clock.getDelta();
const obj = line.visible ? line : segments;
thresholdLine.position.copy(line.position);
thresholdLine.quaternion.copy(line.quaternion);
thresholdSegments.position.copy(segments.position);
thresholdSegments.quaternion.copy(segments.quaternion);
if (params.animate) {
line.rotation.y += delta * 0.1;
segments.rotation.y = line.rotation.y;
}
raycaster.setFromCamera(pointer, camera);
const intersects = raycaster.intersectObject(obj);
if (intersects.length > 0) {
sphereInter.visible = true;
sphereOnLine.visible = true;
sphereInter.position.copy(intersects[0].point);
sphereOnLine.position.copy(intersects[0].pointOnLine);
const index = intersects[0].faceIndex;
const colors = obj.geometry.getAttribute("instanceColorStart");
color.fromBufferAttribute(colors, index);
sphereInter.material.color.copy(color).offsetHSL(0.3, 0, 0);
sphereOnLine.material.color.copy(color).offsetHSL(0.7, 0, 0);
renderer.domElement.style.cursor = "crosshair";
} else {
sphereInter.visible = false;
sphereOnLine.visible = false;
renderer.domElement.style.cursor = "";
}
renderer.render(scene, camera);
stats.update();
}
function switchLine(val) {
switch (val) {
case 0:
line.visible = true;
thresholdLine.visible = true;
segments.visible = false;
thresholdSegments.visible = false;
break;
case 1:
line.visible = false;
thresholdLine.visible = false;
segments.visible = true;
thresholdSegments.visible = true;
break;
}
}
function initGui() {
gui = new GUI();
gui.add(params, "line type", { LineGeometry: 0, LineSegmentsGeometry: 1 }).onChange(function(val) {
switchLine(val);
}).setValue(1);
gui.add(params, "world units").onChange(function(val) {
matLine.worldUnits = val;
matLine.needsUpdate = true;
matThresholdLine.worldUnits = val;
matThresholdLine.needsUpdate = true;
});
gui.add(params, "visualize threshold").onChange(function(val) {
matThresholdLine.visible = val;
});
gui.add(params, "width", 1, 10).onChange(function(val) {
matLine.linewidth = val;
matThresholdLine.linewidth = matLine.linewidth + raycaster.params.Line2.threshold;
});
gui.add(params, "alphaToCoverage").onChange(function(val) {
matLine.alphaToCoverage = val;
});
gui.add(params, "threshold", 0, 10).onChange(function(val) {
raycaster.params.Line2.threshold = val;
matThresholdLine.linewidth = matLine.linewidth + raycaster.params.Line2.threshold;
});
gui.add(params, "translation", 0, 10).onChange(function(val) {
line.position.x = val;
segments.position.x = val;
});
gui.add(params, "animate");
}
}
};
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;