673 lines
26 KiB
JavaScript
673 lines
26 KiB
JavaScript
import * as THREE from 'https://esm.sh/three@0.165.0';
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import { OrbitControls } from 'https://esm.sh/three@0.165.0/examples/jsm/controls/OrbitControls.js';
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const canvas = document.getElementById('scene');
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const progressInput = document.getElementById('progress');
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const progressValue = document.getElementById('progress_value');
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const pageCountInput = document.getElementById('page_count');
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const pageCountValue = document.getElementById('page_count_value');
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const urlParams = new URLSearchParams(window.location.search);
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const renderer = new THREE.WebGLRenderer({ canvas, antialias: true });
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renderer.setPixelRatio(Math.min(window.devicePixelRatio || 1, 2));
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renderer.setClearColor(0x202124, 1);
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const scene = new THREE.Scene();
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const camera = new THREE.PerspectiveCamera(34, 1, 0.1, 30);
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if (urlParams.get('view') === 'profile') {
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camera.position.set(0, 0.82, 5.8);
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} else if (urlParams.get('view') === 'top') {
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camera.position.set(0, 5.8, 0.001);
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} else {
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camera.position.set(0, 3.25, 5.4);
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}
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const controls = new OrbitControls(camera, canvas);
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controls.target.set(0, urlParams.get('view') === 'profile' ? 0.13 : 0.18, 0);
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controls.enableDamping = true;
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controls.minDistance = 2.2;
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controls.maxDistance = 8.0;
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controls.update();
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const book = new THREE.Group();
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scene.add(book);
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const guide = new THREE.GridHelper(5.6, 16, 0x4c4c4c, 0x343434);
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guide.position.y = -0.12;
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scene.add(guide);
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const materials = {
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cover: new THREE.MeshBasicMaterial({ color: 0x2c1810, side: THREE.DoubleSide }),
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spine: new THREE.MeshBasicMaterial({ color: 0x9c1f1f, side: THREE.DoubleSide }),
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pagesLeft: new THREE.MeshBasicMaterial({ color: 0xd8c7a4, side: THREE.DoubleSide }),
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pagesRight: new THREE.MeshBasicMaterial({ color: 0xe7d6b4, side: THREE.DoubleSide }),
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topPage: new THREE.MeshBasicMaterial({ color: 0xf1dfba, side: THREE.DoubleSide }),
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edge: new THREE.MeshBasicMaterial({ color: 0xb99a68, side: THREE.DoubleSide }),
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hinge: new THREE.MeshBasicMaterial({ color: 0x2b0808 })
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};
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const BOOK_PROFILE = {
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tableY: 0,
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coverThickness: 0.03,
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raisedHingeY: 0.056,
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paperContactOffset: 0.0012,
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bundleSpacing: 0.014
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};
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let readingProgress = readInitialProgress();
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let pageCount = readInitialPageCount();
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let lastLengthError = 0;
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let lastSpacingError = 0;
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progressInput.value = readingProgress.toFixed(3);
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progressValue.value = readingProgress.toFixed(2);
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pageCountInput.value = String(pageCount);
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pageCountValue.value = String(pageCount);
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rebuildBook();
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resize();
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animate();
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progressInput.addEventListener('input', () => {
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setReadingProgress(progressInput.value);
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});
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pageCountInput.addEventListener('input', () => {
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setPageCount(pageCountInput.value);
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});
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window.addEventListener('resize', resize);
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window.BookShapeLab = {
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get progress() {
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return readingProgress;
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},
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get pageCount() {
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return pageCount;
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},
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get lastLengthError() {
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return lastLengthError;
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},
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get lastSpacingError() {
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return lastSpacingError;
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},
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setReadingProgress(value) {
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setReadingProgress(value);
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return readingProgress;
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},
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setPageCount(value) {
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setPageCount(value);
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return pageCount;
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}
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};
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function readInitialProgress() {
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const parsed = Number.parseFloat(urlParams.get('progress') ?? '0.25');
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return Number.isFinite(parsed) ? THREE.MathUtils.clamp(parsed, 0, 1) : 0.25;
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}
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function readInitialPageCount() {
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const parsed = Number.parseInt(urlParams.get('pages') ?? '240', 10);
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if (!Number.isFinite(parsed)) return 240;
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return snapPageCount(parsed);
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}
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function snapPageCount(value) {
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return THREE.MathUtils.clamp(Math.round(value / 10) * 10, 40, 600);
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}
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function setReadingProgress(value) {
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const next = THREE.MathUtils.clamp(Number.parseFloat(value), 0, 1);
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if (!Number.isFinite(next)) return;
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readingProgress = next;
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progressInput.value = readingProgress.toFixed(3);
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progressValue.value = readingProgress.toFixed(2);
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rebuildBook();
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}
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function setPageCount(value) {
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const next = snapPageCount(Number.parseFloat(value));
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if (!Number.isFinite(next)) return;
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pageCount = next;
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pageCountInput.value = String(pageCount);
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pageCountValue.value = String(pageCount);
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rebuildBook();
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}
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function rebuildBook() {
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clearGroup(book);
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const coverDepth = 2.34;
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const coverThickness = BOOK_PROFILE.coverThickness;
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const pageWidth = 1.62;
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const pageDepth = 2.24;
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const bundleCount = Math.max(4, Math.round(pageCount / 10));
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const spineWidth = Math.max(0.16, bundleCount * BOOK_PROFILE.bundleSpacing);
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const lines = simulatePageLines(bundleCount, pageWidth, spineWidth);
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lastLengthError = measureLineLengthError(lines, pageWidth);
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lastSpacingError = measureStackSpacingError(lines);
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addCoverAssembly(pageWidth, coverDepth, coverThickness, spineWidth);
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addClothSpine(pageDepth, spineWidth);
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addSimulatedStackBodies(lines, pageDepth);
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addSimulatedPageLines(lines, pageDepth);
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}
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function clearGroup(group) {
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while (group.children.length) {
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const child = group.children.pop();
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child.geometry?.dispose();
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if (Array.isArray(child.material)) {
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child.material.forEach((material) => material.dispose?.());
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}
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}
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}
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function addCoverAssembly(pageWidth, depth, thickness, spineWidth) {
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const cover = new THREE.Mesh(createCoverAssemblyGeometry(pageWidth, depth, thickness, spineWidth), materials.cover);
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book.add(cover);
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}
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function createCoverAssemblyGeometry(pageWidth, depth, thickness, spineWidth) {
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const overhang = 0.055;
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const spineHalf = spineWidth * 0.5;
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const hingeInset = 0.07;
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const outerX = pageWidth + overhang;
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const hingeX = spineHalf + hingeInset;
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const outerTopY = BOOK_PROFILE.tableY + thickness;
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const connectionTopY = BOOK_PROFILE.raisedHingeY;
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const spineTopY = BOOK_PROFILE.tableY + thickness;
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const section = [
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{ x: -outerX, y: outerTopY },
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{ x: -hingeX, y: connectionTopY },
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{ x: -spineHalf, y: spineTopY },
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{ x: spineHalf, y: spineTopY },
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{ x: hingeX, y: connectionTopY },
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{ x: outerX, y: outerTopY }
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];
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const positions = [];
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const uvs = [];
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const indices = [];
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const frontTop = [];
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const backTop = [];
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const frontBottom = [];
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const backBottom = [];
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const push = (x, y, z, u, v) => {
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const index = positions.length / 3;
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positions.push(x, y, z);
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uvs.push(u, v);
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return index;
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};
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section.forEach((point, index) => {
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const u = index / (section.length - 1);
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frontTop[index] = push(point.x, point.y, depth * 0.5, u, 1);
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backTop[index] = push(point.x, point.y, -depth * 0.5, u, 0);
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frontBottom[index] = push(point.x, point.y - thickness, depth * 0.5, u, 1);
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backBottom[index] = push(point.x, point.y - thickness, -depth * 0.5, u, 0);
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});
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for (let i = 0; i < section.length - 1; i += 1) {
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indices.push(frontTop[i], backTop[i], frontTop[i + 1], frontTop[i + 1], backTop[i], backTop[i + 1]);
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indices.push(frontBottom[i], frontBottom[i + 1], backBottom[i], frontBottom[i + 1], backBottom[i + 1], backBottom[i]);
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indices.push(frontTop[i], frontTop[i + 1], frontBottom[i], frontTop[i + 1], frontBottom[i + 1], frontBottom[i]);
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indices.push(backTop[i], backBottom[i], backTop[i + 1], backTop[i + 1], backBottom[i], backBottom[i + 1]);
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}
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const last = section.length - 1;
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indices.push(frontTop[0], frontBottom[0], backTop[0], backTop[0], frontBottom[0], backBottom[0]);
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indices.push(frontTop[last], backTop[last], frontBottom[last], backTop[last], backBottom[last], frontBottom[last]);
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const geometry = new THREE.BufferGeometry();
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geometry.setIndex(indices);
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geometry.setAttribute('position', new THREE.Float32BufferAttribute(positions, 3));
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geometry.setAttribute('uv', new THREE.Float32BufferAttribute(uvs, 2));
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geometry.computeVertexNormals();
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return geometry;
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}
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function addClothSpine(depth, spineWidth) {
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const spine = new THREE.Mesh(createClothSpineGeometry(depth, spineWidth), materials.spine);
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book.add(spine);
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}
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function createClothSpineGeometry(depth, spineWidth) {
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const profile = [];
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for (let i = 0; i <= 32; i += 1) {
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const u = i / 32;
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profile.push(spineCurvePoint(u, spineWidth));
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}
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const positions = [];
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const indices = [];
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const front = [];
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const back = [];
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const push = (point, z) => {
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const index = positions.length / 3;
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positions.push(point.x, point.y, z);
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return index;
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};
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profile.forEach((point) => {
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front.push(push(point, depth * 0.5 + 0.012));
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back.push(push(point, -depth * 0.5 - 0.012));
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});
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for (let i = 0; i < profile.length - 1; i += 1) {
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indices.push(front[i], back[i], front[i + 1]);
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indices.push(front[i + 1], back[i], back[i + 1]);
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}
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const geometry = new THREE.BufferGeometry();
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geometry.setIndex(indices);
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geometry.setAttribute('position', new THREE.Float32BufferAttribute(positions, 3));
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geometry.computeVertexNormals();
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return geometry;
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}
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function spineCurvePoint(t, spineWidth) {
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const radiusX = spineWidth * 0.42;
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const radiusY = 0.018;
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const baseY = BOOK_PROFILE.tableY + BOOK_PROFILE.coverThickness + 0.002;
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const theta = Math.PI * (1 - THREE.MathUtils.clamp(t, 0, 1));
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return {
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t: THREE.MathUtils.clamp(t, 0, 1),
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x: Math.cos(theta) * radiusX,
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y: baseY + Math.sin(theta) * radiusY
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};
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}
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function simulatePageLines(bundleCount, pageWidth, spineWidth) {
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const lines = [];
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const segments = 16;
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const stepLength = pageWidth / segments;
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const entries = [];
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const spineSamples = sampleSpineByArc(bundleCount, spineWidth);
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const leftLimit = Math.floor((bundleCount - 1) * readingProgress);
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for (let index = 0; index < bundleCount; index += 1) {
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const t = spineSamples[index].t;
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const side = index <= leftLimit ? -1 : 1;
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entries.push({ index, t, side });
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}
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[-1, 1].forEach((side) => {
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const sideEntries = entries.filter((entry) => entry.side === side);
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sideEntries.forEach((entry, rank) => {
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entry.rank = rank;
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entry.sideCount = sideEntries.length;
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});
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});
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[-1, 1].forEach((side) => {
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const sideEntries = entries
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.filter((entry) => entry.side === side)
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.sort((a, b) => side < 0 ? a.t - b.t : b.t - a.t);
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if (!sideEntries.length) return;
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const bottomEntry = sideEntries[0];
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const bottomAnchor = spineCurvePoint(bottomEntry.t, spineWidth);
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const bottomTarget = restingTarget(side, pageWidth, 0, sideEntries.length);
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const bottomPoints = initialPageLine(bottomAnchor, bottomTarget, segments);
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relaxPageLine(bottomPoints, bottomAnchor, stepLength, side, 0, bundleCount);
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keepPageAboveCover(bottomPoints, side, bundleCount);
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sideEntries.forEach((entry, rank) => {
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const anchor = spineCurvePoint(entry.t, spineWidth);
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const points = rank === 0
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? bottomPoints.map((point) => ({ ...point }))
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: offsetPageLine(bottomPoints, anchor, rank * BOOK_PROFILE.bundleSpacing);
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keepPageAboveCover(points, side, bundleCount);
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lines.push({ index: entry.index, t: entry.t, side, anchor, points, endpoint: points[points.length - 1] });
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});
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});
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enforceStackConstraints(lines, stepLength, bundleCount);
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return lines;
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}
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function measureLineLengthError(lines, pageWidth) {
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return lines.reduce((maxError, line) => {
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let length = 0;
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for (let i = 0; i < line.points.length - 1; i += 1) {
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length += Math.hypot(line.points[i + 1].x - line.points[i].x, line.points[i + 1].y - line.points[i].y);
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}
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return Math.max(maxError, Math.abs(length - pageWidth));
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}, 0);
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}
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function measureStackSpacingError(lines) {
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let maxError = 0;
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[-1, 1].forEach((side) => {
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const sideLines = lines
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.filter((line) => line.side === side)
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.sort((a, b) => side < 0 ? a.t - b.t : b.t - a.t);
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for (let row = 1; row < sideLines.length; row += 1) {
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const lower = sideLines[row - 1];
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const upper = sideLines[row];
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for (let col = 0; col < upper.points.length; col += 1) {
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const distance = Math.hypot(upper.points[col].x - lower.points[col].x, upper.points[col].y - lower.points[col].y);
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maxError = Math.max(maxError, Math.abs(distance - BOOK_PROFILE.bundleSpacing));
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}
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}
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});
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return maxError;
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}
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function sampleSpineByArc(count, spineWidth) {
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const samples = [];
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const steps = 240;
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let length = 0;
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let previous = spineCurvePoint(0, spineWidth);
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samples.push({ point: previous, length });
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for (let i = 1; i <= steps; i += 1) {
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const t = i / steps;
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const point = spineCurvePoint(t, spineWidth);
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length += Math.hypot(point.x - previous.x, point.y - previous.y);
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samples.push({ point, length });
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previous = point;
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}
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const points = [];
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for (let i = 0; i < count; i += 1) {
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const target = count === 1 ? length * 0.5 : length * (i / (count - 1));
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const found = samples.findIndex((sample) => sample.length >= target);
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if (found <= 0) {
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points.push(samples[0].point);
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continue;
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}
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const before = samples[found - 1];
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const after = samples[found];
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const span = after.length - before.length || 1;
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const t = THREE.MathUtils.lerp(before.point.t, after.point.t, (target - before.length) / span);
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points.push(spineCurvePoint(t, spineWidth));
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}
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return points;
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}
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function initialPageLine(anchor, target, segments) {
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const points = [];
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for (let i = 0; i <= segments; i += 1) {
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const u = i / segments;
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const sag = 0.04 * Math.sin(Math.PI * u);
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points.push({
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x: THREE.MathUtils.lerp(anchor.x, target.x, u),
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y: THREE.MathUtils.lerp(anchor.y, target.y, u) - sag * u
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});
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}
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return points;
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}
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function restingTarget(side, pageWidth, rank, sideCount) {
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const local = sideCount <= 1 ? 0 : rank / (sideCount - 1);
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const foreCurve = 0.11 * Math.sin(Math.PI * local);
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const x = side * (pageWidth - foreCurve);
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const y = BOOK_PROFILE.coverThickness + BOOK_PROFILE.paperContactOffset + rank * BOOK_PROFILE.bundleSpacing + 0.002 * Math.sin(Math.PI * local);
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return { x, y };
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}
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function relaxPageLine(points, anchor, stepLength, side, local, bundleCount) {
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const gravity = 0.00072;
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const stackPressure = 0.0011 * (1 - local);
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const bendStrength = 0.52;
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const iterations = 72;
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for (let iteration = 0; iteration < iterations; iteration += 1) {
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points[0].x = anchor.x;
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points[0].y = anchor.y;
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for (let i = 1; i < points.length; i += 1) {
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const u = i / (points.length - 1);
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points[i].y -= gravity * u + stackPressure * u * u;
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}
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applyBendingResistance(points, bendStrength);
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for (let pass = 0; pass < 3; pass += 1) {
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points[0].x = anchor.x;
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points[0].y = anchor.y;
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enforceLineLength(points, anchor, stepLength, 3);
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keepPageAboveCover(points, side, bundleCount);
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}
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}
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}
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function applyBendingResistance(points, strength) {
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const updates = points.map((point) => ({ x: point.x, y: point.y }));
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for (let i = 1; i < points.length - 1; i += 1) {
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const previous = points[i - 1];
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const current = points[i];
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const next = points[i + 1];
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updates[i].x += (previous.x + next.x - current.x * 2) * strength;
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updates[i].y += (previous.y + next.y - current.y * 2) * strength;
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}
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for (let i = 1; i < points.length - 1; i += 1) {
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points[i].x = updates[i].x;
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points[i].y = updates[i].y;
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}
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}
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function enforceLineLength(points, anchor, stepLength, passes) {
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for (let pass = 0; pass < passes; pass += 1) {
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points[0].x = anchor.x;
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points[0].y = anchor.y;
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for (let i = 0; i < points.length - 1; i += 1) {
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constrainSegment(points[i], points[i + 1], stepLength, i === 0);
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}
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for (let i = points.length - 2; i >= 0; i -= 1) {
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constrainSegment(points[i], points[i + 1], stepLength, i === 0);
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}
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}
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}
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function constrainSegment(a, b, length, anchorA) {
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const dx = b.x - a.x;
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const dy = b.y - a.y;
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const distance = Math.hypot(dx, dy) || 0.0001;
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const correction = (distance - length) / distance;
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if (anchorA) {
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b.x -= dx * correction;
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b.y -= dy * correction;
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return;
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}
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a.x += dx * correction * 0.5;
|
|
a.y += dy * correction * 0.5;
|
|
b.x -= dx * correction * 0.5;
|
|
b.y -= dy * correction * 0.5;
|
|
}
|
|
|
|
function keepPageAboveCover(points, side, bundleCount) {
|
|
for (let i = 1; i < points.length; i += 1) {
|
|
const clearance = BOOK_PROFILE.paperContactOffset + 0.0002 * bundleCount;
|
|
points[i].y = Math.max(points[i].y, coverTopYAtX(points[i].x) + clearance);
|
|
points[i].x = side < 0 ? Math.min(points[i].x, -0.01) : Math.max(points[i].x, 0.01);
|
|
}
|
|
}
|
|
|
|
function enforceStackConstraints(lines, stepLength, bundleCount) {
|
|
const iterations = 44;
|
|
[-1, 1].forEach((side) => {
|
|
const sideLines = lines
|
|
.filter((line) => line.side === side)
|
|
.sort((a, b) => side < 0 ? a.t - b.t : b.t - a.t);
|
|
for (let iteration = 0; iteration < iterations; iteration += 1) {
|
|
sideLines.forEach((line) => {
|
|
line.points[0].x = line.anchor.x;
|
|
line.points[0].y = line.anchor.y;
|
|
applyBendingResistance(line.points, 0.22);
|
|
enforceLineLength(line.points, line.anchor, stepLength, 3);
|
|
keepPageAboveCover(line.points, side, bundleCount);
|
|
});
|
|
|
|
for (let row = 1; row < sideLines.length; row += 1) {
|
|
const lower = sideLines[row - 1];
|
|
const upper = sideLines[row];
|
|
for (let col = 1; col < upper.points.length; col += 1) {
|
|
const normal = upwardNormalAt(lower.points, col);
|
|
const targetX = lower.points[col].x + normal.x * BOOK_PROFILE.bundleSpacing;
|
|
const targetY = lower.points[col].y + normal.y * BOOK_PROFILE.bundleSpacing;
|
|
upper.points[col].x = THREE.MathUtils.lerp(upper.points[col].x, targetX, 0.28);
|
|
upper.points[col].y = Math.max(upper.points[col].y, THREE.MathUtils.lerp(upper.points[col].y, targetY, 0.42));
|
|
}
|
|
upper.points[0].x = upper.anchor.x;
|
|
upper.points[0].y = upper.anchor.y;
|
|
applyBendingResistance(upper.points, 0.2);
|
|
enforceLineLength(upper.points, upper.anchor, stepLength, 3);
|
|
keepPageAboveCover(upper.points, side, bundleCount);
|
|
}
|
|
}
|
|
sideLines.forEach((line) => {
|
|
applyBendingResistance(line.points, 0.32);
|
|
enforceLineLength(line.points, line.anchor, stepLength, 10);
|
|
keepPageAboveCover(line.points, side, bundleCount);
|
|
enforceLineLength(line.points, line.anchor, stepLength, 6);
|
|
});
|
|
sideLines.forEach((line) => {
|
|
line.endpoint = line.points[line.points.length - 1];
|
|
});
|
|
});
|
|
}
|
|
|
|
function offsetPageLine(basePoints, anchor, distance) {
|
|
return basePoints.map((point, index) => {
|
|
if (index === 0) return { x: anchor.x, y: anchor.y };
|
|
const normal = upwardNormalAt(basePoints, index);
|
|
return {
|
|
x: point.x + normal.x * distance,
|
|
y: point.y + normal.y * distance
|
|
};
|
|
});
|
|
}
|
|
|
|
function upwardNormalAt(points, index) {
|
|
const previous = points[Math.max(0, index - 1)];
|
|
const next = points[Math.min(points.length - 1, index + 1)];
|
|
const dx = next.x - previous.x;
|
|
const dy = next.y - previous.y;
|
|
const length = Math.hypot(dx, dy) || 0.0001;
|
|
let nx = -dy / length;
|
|
let ny = dx / length;
|
|
if (ny < 0) {
|
|
nx = -nx;
|
|
ny = -ny;
|
|
}
|
|
return { x: nx, y: ny };
|
|
}
|
|
|
|
function coverTopYAtX(x) {
|
|
const ax = Math.abs(x);
|
|
const spineHalf = currentSpineHalf();
|
|
const hingeX = spineHalf + 0.07;
|
|
const outerX = 1.62 + 0.055;
|
|
if (ax <= spineHalf) return BOOK_PROFILE.coverThickness;
|
|
if (ax <= hingeX) {
|
|
const t = (ax - spineHalf) / (hingeX - spineHalf);
|
|
return THREE.MathUtils.lerp(BOOK_PROFILE.coverThickness, BOOK_PROFILE.raisedHingeY, t);
|
|
}
|
|
const t = THREE.MathUtils.clamp((ax - hingeX) / (outerX - hingeX), 0, 1);
|
|
return THREE.MathUtils.lerp(BOOK_PROFILE.raisedHingeY, BOOK_PROFILE.coverThickness, t);
|
|
}
|
|
|
|
function currentSpineHalf() {
|
|
return Math.max(0.16, Math.round(pageCount / 10) * BOOK_PROFILE.bundleSpacing) * 0.5;
|
|
}
|
|
|
|
function addSimulatedPageLines(lines, depth) {
|
|
const leftMaterial = new THREE.LineBasicMaterial({ color: 0x8f7750, transparent: true, opacity: 0.72 });
|
|
const rightMaterial = new THREE.LineBasicMaterial({ color: 0x9a8058, transparent: true, opacity: 0.72 });
|
|
const z = depth * 0.5 + 0.11;
|
|
lines.forEach((line) => {
|
|
const points = smoothLinePoints(line.points, 4).map((point) => new THREE.Vector3(point.x, point.y, z));
|
|
book.add(new THREE.Line(new THREE.BufferGeometry().setFromPoints(points), line.side < 0 ? leftMaterial : rightMaterial));
|
|
});
|
|
}
|
|
|
|
function addSimulatedStackBodies(lines, depth) {
|
|
[-1, 1].forEach((side) => {
|
|
const sideLines = lines.filter((line) => line.side === side);
|
|
if (sideLines.length < 2) return;
|
|
const material = side < 0 ? materials.pagesLeft : materials.pagesRight;
|
|
book.add(new THREE.Mesh(createLoftedLineBody(sideLines, depth), material));
|
|
book.add(new THREE.Line(createEndpointPolyline(sideLines, depth), new THREE.LineBasicMaterial({ color: 0xb99a68, transparent: true, opacity: 0.62 })));
|
|
});
|
|
}
|
|
|
|
function createLoftedLineBody(lines, depth) {
|
|
const positions = [];
|
|
const indices = [];
|
|
const smoothLines = lines.map((line) => smoothLinePoints(line.points, 4));
|
|
const push = (point, z) => {
|
|
const index = positions.length / 3;
|
|
positions.push(point.x, point.y, z);
|
|
return index;
|
|
};
|
|
const front = smoothLines.map((points) => points.map((point) => push(point, depth * 0.5 + 0.09)));
|
|
const back = smoothLines.map((points) => points.map((point) => push(point, -depth * 0.5 + 0.09)));
|
|
for (let row = 0; row < smoothLines.length - 1; row += 1) {
|
|
for (let col = 0; col < smoothLines[row].length - 1; col += 1) {
|
|
indices.push(front[row][col], front[row + 1][col], front[row][col + 1]);
|
|
indices.push(front[row][col + 1], front[row + 1][col], front[row + 1][col + 1]);
|
|
indices.push(back[row][col], back[row][col + 1], back[row + 1][col]);
|
|
indices.push(back[row][col + 1], back[row + 1][col + 1], back[row + 1][col]);
|
|
}
|
|
}
|
|
for (let row = 0; row < smoothLines.length - 1; row += 1) {
|
|
const last = smoothLines[row].length - 1;
|
|
indices.push(front[row][last], front[row + 1][last], back[row][last]);
|
|
indices.push(front[row + 1][last], back[row + 1][last], back[row][last]);
|
|
}
|
|
for (let col = 0; col < smoothLines[0].length - 1; col += 1) {
|
|
const bottomRow = 0;
|
|
const topRow = smoothLines.length - 1;
|
|
indices.push(front[bottomRow][col], front[bottomRow][col + 1], back[bottomRow][col]);
|
|
indices.push(front[bottomRow][col + 1], back[bottomRow][col + 1], back[bottomRow][col]);
|
|
indices.push(front[topRow][col], back[topRow][col], front[topRow][col + 1]);
|
|
indices.push(front[topRow][col + 1], back[topRow][col], back[topRow][col + 1]);
|
|
}
|
|
for (let row = 0; row < smoothLines.length - 1; row += 1) {
|
|
indices.push(front[row][0], back[row][0], front[row + 1][0]);
|
|
indices.push(front[row + 1][0], back[row][0], back[row + 1][0]);
|
|
}
|
|
const geometry = new THREE.BufferGeometry();
|
|
geometry.setIndex(indices);
|
|
geometry.setAttribute('position', new THREE.Float32BufferAttribute(positions, 3));
|
|
geometry.computeVertexNormals();
|
|
return geometry;
|
|
}
|
|
|
|
function createEndpointPolyline(lines, depth) {
|
|
const points = lines.map((line) => new THREE.Vector3(line.endpoint.x, line.endpoint.y, depth * 0.5 + 0.112));
|
|
return new THREE.BufferGeometry().setFromPoints(points);
|
|
}
|
|
|
|
function smoothLinePoints(points, subdivisions) {
|
|
const result = [];
|
|
for (let i = 0; i < points.length - 1; i += 1) {
|
|
const p0 = points[Math.max(0, i - 1)];
|
|
const p1 = points[i];
|
|
const p2 = points[i + 1];
|
|
const p3 = points[Math.min(points.length - 1, i + 2)];
|
|
for (let step = 0; step < subdivisions; step += 1) {
|
|
const t = step / subdivisions;
|
|
result.push(catmullRomPoint(p0, p1, p2, p3, t));
|
|
}
|
|
}
|
|
result.push(points[points.length - 1]);
|
|
return result;
|
|
}
|
|
|
|
function catmullRomPoint(p0, p1, p2, p3, t) {
|
|
const tt = t * t;
|
|
const ttt = tt * t;
|
|
return {
|
|
x: 0.5 * ((2 * p1.x) + (-p0.x + p2.x) * t + (2 * p0.x - 5 * p1.x + 4 * p2.x - p3.x) * tt + (-p0.x + 3 * p1.x - 3 * p2.x + p3.x) * ttt),
|
|
y: 0.5 * ((2 * p1.y) + (-p0.y + p2.y) * t + (2 * p0.y - 5 * p1.y + 4 * p2.y - p3.y) * tt + (-p0.y + 3 * p1.y - 3 * p2.y + p3.y) * ttt)
|
|
};
|
|
}
|
|
|
|
function resize() {
|
|
const width = window.innerWidth;
|
|
const height = window.innerHeight;
|
|
renderer.setSize(width, height, false);
|
|
camera.aspect = width / height;
|
|
camera.updateProjectionMatrix();
|
|
}
|
|
|
|
function animate() {
|
|
requestAnimationFrame(animate);
|
|
if (urlParams.get('animate') === '1') {
|
|
const t = performance.now() * 0.00035;
|
|
setReadingProgress(0.5 + Math.sin(t) * 0.48);
|
|
}
|
|
controls.update();
|
|
renderer.render(scene, camera);
|
|
}
|