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<!-- Licensed under a BSD license. See license.html for license -->
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
<title>Three.js - Custom BufferGeometry - Dynamic</title>
<style>
html, body {
height: 100%;
margin: 0;
}
#c {
width: 100%;
height: 100%;
display: block;
}
</style>
</head>
<body>
<canvas id="c"></canvas>
</body>
<!-- Import maps polyfill -->
<!-- Remove this when import maps will be widely supported -->
<script async src="https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js"></script>
<script type="importmap">
{
"imports": {
"three": "../../build/three.module.js"
}
}
</script>
<script type="module">
import * as THREE from 'three';
function main() {
const canvas = document.querySelector('#c');
const renderer = new THREE.WebGLRenderer({canvas});
const fov = 75;
const aspect = 2; // the canvas default
const near = 0.1;
const far = 100;
const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
camera.position.z = 3;
const scene = new THREE.Scene();
function addLight(...pos) {
const color = 0xFFFFFF;
const intensity = 1;
const light = new THREE.DirectionalLight(color, intensity);
light.position.set(...pos);
scene.add(light);
}
addLight(-1, 2, 4);
addLight( 2, -2, 3);
function makeSpherePositions(segmentsAround, segmentsDown) {
const numVertices = segmentsAround * segmentsDown * 6;
const numComponents = 3;
const positions = new Float32Array(numVertices * numComponents);
const indices = [];
const longHelper = new THREE.Object3D();
const latHelper = new THREE.Object3D();
const pointHelper = new THREE.Object3D();
longHelper.add(latHelper);
latHelper.add(pointHelper);
pointHelper.position.z = 1;
const temp = new THREE.Vector3();
function getPoint(lat, long) {
latHelper.rotation.x = lat;
longHelper.rotation.y = long;
longHelper.updateMatrixWorld(true);
return pointHelper.getWorldPosition(temp).toArray();
}
let posNdx = 0;
let ndx = 0;
for (let down = 0; down < segmentsDown; ++down) {
const v0 = down / segmentsDown;
const v1 = (down + 1) / segmentsDown;
const lat0 = (v0 - 0.5) * Math.PI;
const lat1 = (v1 - 0.5) * Math.PI;
for (let across = 0; across < segmentsAround; ++across) {
const u0 = across / segmentsAround;
const u1 = (across + 1) / segmentsAround;
const long0 = u0 * Math.PI * 2;
const long1 = u1 * Math.PI * 2;
positions.set(getPoint(lat0, long0), posNdx); posNdx += numComponents;
positions.set(getPoint(lat1, long0), posNdx); posNdx += numComponents;
positions.set(getPoint(lat0, long1), posNdx); posNdx += numComponents;
positions.set(getPoint(lat1, long1), posNdx); posNdx += numComponents;
indices.push(
ndx, ndx + 1, ndx + 2,
ndx + 2, ndx + 1, ndx + 3,
);
ndx += 4;
}
}
return {positions, indices};
}
const segmentsAround = 24;
const segmentsDown = 16;
const {positions, indices} = makeSpherePositions(segmentsAround, segmentsDown);
const normals = positions.slice();
const geometry = new THREE.BufferGeometry();
const positionNumComponents = 3;
const normalNumComponents = 3;
const positionAttribute = new THREE.BufferAttribute(positions, positionNumComponents);
positionAttribute.setUsage(THREE.DynamicDrawUsage);
geometry.setAttribute(
'position',
positionAttribute);
geometry.setAttribute(
'normal',
new THREE.BufferAttribute(normals, normalNumComponents));
geometry.setIndex(indices);
function makeInstance(geometry, color, x) {
const material = new THREE.MeshPhongMaterial({
color,
side: THREE.DoubleSide,
shininess: 100,
});
const cube = new THREE.Mesh(geometry, material);
scene.add(cube);
cube.position.x = x;
return cube;
}
const cubes = [
makeInstance(geometry, 0xFF0000, 0),
];
function resizeRendererToDisplaySize(renderer) {
const canvas = renderer.domElement;
const width = canvas.clientWidth;
const height = canvas.clientHeight;
const needResize = canvas.width !== width || canvas.height !== height;
if (needResize) {
renderer.setSize(width, height, false);
}
return needResize;
}
const temp = new THREE.Vector3();
function render(time) {
time *= 0.001;
if (resizeRendererToDisplaySize(renderer)) {
const canvas = renderer.domElement;
camera.aspect = canvas.clientWidth / canvas.clientHeight;
camera.updateProjectionMatrix();
}
for (let i = 0; i < positions.length; i += 3) {
const quad = (i / 12 | 0);
const ringId = quad / segmentsAround | 0;
const ringQuadId = quad % segmentsAround;
const ringU = ringQuadId / segmentsAround;
const angle = ringU * Math.PI * 2;
temp.fromArray(normals, i);
temp.multiplyScalar(THREE.MathUtils.lerp(1, 1.4, Math.sin(time + ringId + angle) * .5 + .5));
temp.toArray(positions, i);
}
positionAttribute.needsUpdate = true;
cubes.forEach((cube, ndx) => {
const speed = -0.2 + ndx * .1;
const rot = time * speed;
cube.rotation.y = rot;
});
renderer.render(scene, camera);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
}
main();
</script>
</html>