📄 main.ts
import "./style.css";
import "./audioSelector";
import * as THREE from "three";
import { OrbitControls } from "three/examples/jsm/controls/OrbitControls.js";
import { NURBSCurve } from "three/examples/jsm/curves/NURBSCurve.js";

const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true });
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);

const camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 0.1, 2000);
camera.position.set(0, 1, 10);

const controls = new OrbitControls(camera, renderer.domElement);
controls.enableDamping = true;
controls.update();

window.addEventListener("resize", () => {
    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();
    renderer.setSize(window.innerWidth, window.innerHeight);
});

const scene = new THREE.Scene();
scene.add(new THREE.AmbientLight(0xffffff));
scene.add(
    (() => {
        const lights = new THREE.DirectionalLight(0xffffff, 1);
        lights.position.set(-1, -3, -2);
        return lights;
    })(),
);
scene.add(
    (() => {
        const lights = new THREE.DirectionalLight(0xffffff, 3);
        lights.position.set(1, 3, 2);
        return lights;
    })(),
);
const material = new THREE.MeshPhongMaterial({ color: 0xbada55, side: THREE.DoubleSide });
let curve = (() => {
    const curve = new NURBSCurve(
        3,
        [0, 0, 0, 0, 0.5, 1, 1, 1, 1],
        [
            new THREE.Vector4(-1, -1, 0, 1),
            new THREE.Vector4(-1, 1, 0, 1),
            new THREE.Vector4(0, -1, 0, 1),
            new THREE.Vector4(1, 1, 0, 1),
            new THREE.Vector4(1, -1, 0, 1),
        ],
    );
    const geometry = new THREE.TubeGeometry(curve, 16, 0.1, 8, false);
    return new THREE.Mesh(geometry, material);
})();
scene.add(curve);
(window as any).updateCurve = (heights: Uint8Array) => {
    scene.remove(curve);

    const degree = 3;
    const knots = new Array<number>();
    const controlPoints = new Array<THREE.Vector4>();

    for (let i = 0; i <= degree; i++) {
        knots.push(0);
    }
    for (let i = 0; i < heights.length; i++) {
        controlPoints.push(new THREE.Vector4((i - heights.length / 2) * 0.1, heights[i] / 256, 0, 1));
        knots.push(THREE.MathUtils.clamp((i + 1) / (heights.length - degree), 0, 1));
    }

    const nurbs = new NURBSCurve(degree, knots, controlPoints);
    const geometry = new THREE.TubeGeometry(nurbs, heights.length, 0.05, 8, false);
    curve = new THREE.Mesh(geometry, material);
    scene.add(curve);
};

window.requestAnimationFrame(animate);
function animate() {
    controls.update();
    renderer.render(scene, camera);
    window.requestAnimationFrame(animate);
}