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<script async src="https://ga.jspm.io/npm:[email protected]/dist/es-module-shims.js" crossorigin="anonymous"></script>
<script type='importmap-shim'>
{
"imports": {
"three": "https://unpkg.com/[email protected]/build/three.module.js",
"three/": "https://unpkg.com/[email protected]/",
"omega/": "https://cdn.jsdelivr.net/gh/ycw/[email protected]/",
"postprocessing/": "https://unpkg.com/[email protected]/"
}
}
</script>
<script defer type='module-shim'>
import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
import { Strip, StripGeometry, StripHelper, UvPreset } from 'omega/dist/Strip.js'
import * as PP from 'postprocessing/build/postprocessing.esm.js'
// ----
// main
// ----
const renderer = new THREE.WebGLRenderer();
const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera(75, 2, .1, 100);
const controls = new OrbitControls(camera, renderer.domElement);
scene.background = new THREE.Color('white');
controls.target.set(0, .8, 0);
camera.position.set(1, 1, .8);
controls.autoRotate = true;
controls.enableDamping = true;
renderer.shadowMap.enabled = true;
const light = new THREE.DirectionalLight('white', 1);
light.position.set(2, 2, 1);
scene.add(light);
light.castShadow = true;
light.shadow.bias = -0.0001;
scene.add(new THREE.AmbientLight('white', 1));
const N_SEG = 20;
const BREADTH = .5;
const curve = new THREE.CatmullRomCurve3([
new THREE.Vector3(0, 1, 0),
new THREE.Vector3(0, 0, 0),
new THREE.Vector3(0, -1, 0),
new THREE.Vector3(0, -2, 0),
], false);
const radius_fn = (i, I) => .2 + 1.5 * i / I;
const tilt_fn = (i, I) => 5 * Math.PI * i / I + Math.PI * .5;
const strip = new Strip(curve, radius_fn, tilt_fn);
const frames = strip.computeFrames(N_SEG);
const strip_geom = new StripGeometry(strip, N_SEG);
// scene.add(new StripHelper(strip, N_SEG));
function f(strip_geom, radius_fn, frames, result) { // random pos lying on strip
const ab_pos = strip_geom.getAttribute('position').array;
const n_idx = ab_pos.length / 6; // /3/2
const idx = Math.random() * n_idx | 0;
const pa = new THREE.Vector3(...ab_pos.subarray(idx * 6, idx * 6 + 3));
const pb = new THREE.Vector3(...ab_pos.subarray(idx * 6 + 3, idx * 6 + 6));
const pa2pb = new THREE.Vector3().subVectors(pb, pa);
const len = 2 * radius_fn(idx, n_idx);
pa2pb.normalize().multiplyScalar(len * Math.random());
pa.add(pa2pb);
const [B, N, T] = frames[idx];
result.makeBasis(B, N, T).setPosition(pa);
}
// texture by Lena Albers - https://unsplash.com/photos/px-JsA27fbQ
const url = 'https://images.unsplash.com/photo-1628071616999-0660c371c465?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxlZGl0b3JpYWwtZmVlZHw4MXx8fGVufDB8fHx8&auto=format&fit=crop&w=500&q=60';
const tex = new THREE.TextureLoader().load(url);
{ // https://codepen.io/ycw/pen/KKZgPyB
const N_INST = 1000;
const strip = new Strip(new THREE.CatmullRomCurve3([
new THREE.Vector3(.2, .2, 0),
new THREE.Vector3(.4, .5, 0),
new THREE.Vector3(.4, .1, 0),
new THREE.Vector3(0, 0, 0),
]), (i, I) => .5 * (i / I), (i, I) => Math.PI * 0.4 * i / I);
const geom = new StripGeometry(strip, 32, UvPreset.strip[0]);
const mat = new THREE.MeshPhysicalMaterial({ map: tex, side: THREE.DoubleSide, roughness: 1, alphaMap: tex, alphaTest: .2 });
const mesh = new THREE.InstancedMesh(geom, mat, N_INST);
const $mat_basis = new THREE.Matrix4();
const $mat_r = new THREE.Matrix4(); // ry
const $mat_s = new THREE.Matrix4(); // scale
const $col = new THREE.Color();
for (let i = 0; i < N_INST; ++i) {
$mat_r.makeRotationY(Math.PI * Math.random() * 2);
$mat_s.makeScale(Math.random(), Math.random(), Math.random());
f(strip_geom, radius_fn, frames, $mat_basis);
mesh.setMatrixAt(i, $mat_basis.multiply($mat_r).multiply($mat_s));
mesh.setColorAt(i, $col.setHSL(Math.random(), .5, .5 + .5 * Math.random()));
}
scene.add(mesh);
mesh.castShadow = true;
mesh.receiveShadow = true;
}
{
const geom = new THREE.CylinderGeometry(.1, .1, 2.6);
const mat = new THREE.MeshPhysicalMaterial({ roughness: 1, map: tex, color: '#222' });
const mesh = new THREE.Mesh(geom, mat);
scene.add(mesh);
}
// ----
// render
// ----
const composer = new PP.EffectComposer(renderer);
composer.addPass(new PP.RenderPass(scene, camera));
composer.addPass(new PP.EffectPass(
camera,
new PP.BrightnessContrastEffect({ contrast: +.5 }),
new PP.BloomEffect({
luminanceThreshold: .1,
intensity: 1
})
));
renderer.setAnimationLoop((t) => {
composer.render();
controls.update();
tex.offset.y = -1 + Math.min(t * 0.00033, 2)/2;
});
// ----
// view
// ----
function resize(w, h, dpr = devicePixelRatio) {
composer.setSize(w, h);
camera.aspect = w / h;
camera.updateProjectionMatrix();
}
addEventListener('resize', () => resize(innerWidth, innerHeight));
dispatchEvent(new Event('resize'));
document.body.prepend(renderer.domElement);
</script>
canvas {
display: block; width: 100%; height: 100vh;
cursor: grab;
position: fixed; top: 0; left: 0;
}
Also see: Tab Triggers