You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

223 lines
5.3 KiB

2 years ago
<!DOCTYPE html>
<html lang="en">
<head>
<title>three.js webgl - buffergeometry - uint</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
<link type="text/css" rel="stylesheet" href="main.css">
</head>
<body>
<div id="container"></div>
<div id="info"><a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl - buffergeometry - uint</div>
<!-- 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",
"three/addons/": "./jsm/"
}
}
</script>
<script type="module">
import * as THREE from 'three';
import Stats from 'three/addons/libs/stats.module.js';
let container, stats;
let camera, scene, renderer;
let mesh;
init();
animate();
function init() {
container = document.getElementById( 'container' );
//
camera = new THREE.PerspectiveCamera( 27, window.innerWidth / window.innerHeight, 1, 3500 );
camera.position.z = 2750;
scene = new THREE.Scene();
scene.background = new THREE.Color( 0x050505 );
scene.fog = new THREE.Fog( 0x050505, 2000, 3500 );
//
scene.add( new THREE.AmbientLight( 0x444444 ) );
const light1 = new THREE.DirectionalLight( 0xffffff, 0.5 );
light1.position.set( 1, 1, 1 );
scene.add( light1 );
const light2 = new THREE.DirectionalLight( 0xffffff, 1.5 );
light2.position.set( 0, - 1, 0 );
scene.add( light2 );
//
const triangles = 500000;
const geometry = new THREE.BufferGeometry();
const positions = [];
const normals = [];
const colors = [];
const color = new THREE.Color();
const n = 800, n2 = n / 2; // triangles spread in the cube
const d = 12, d2 = d / 2; // individual triangle size
const pA = new THREE.Vector3();
const pB = new THREE.Vector3();
const pC = new THREE.Vector3();
const cb = new THREE.Vector3();
const ab = new THREE.Vector3();
for ( let i = 0; i < triangles; i ++ ) {
// positions
const x = Math.random() * n - n2;
const y = Math.random() * n - n2;
const z = Math.random() * n - n2;
const ax = x + Math.random() * d - d2;
const ay = y + Math.random() * d - d2;
const az = z + Math.random() * d - d2;
const bx = x + Math.random() * d - d2;
const by = y + Math.random() * d - d2;
const bz = z + Math.random() * d - d2;
const cx = x + Math.random() * d - d2;
const cy = y + Math.random() * d - d2;
const cz = z + Math.random() * d - d2;
positions.push( ax, ay, az );
positions.push( bx, by, bz );
positions.push( cx, cy, cz );
// flat face normals
pA.set( ax, ay, az );
pB.set( bx, by, bz );
pC.set( cx, cy, cz );
cb.subVectors( pC, pB );
ab.subVectors( pA, pB );
cb.cross( ab );
cb.normalize();
const nx = cb.x;
const ny = cb.y;
const nz = cb.z;
normals.push( nx * 32767, ny * 32767, nz * 32767 );
normals.push( nx * 32767, ny * 32767, nz * 32767 );
normals.push( nx * 32767, ny * 32767, nz * 32767 );
// colors
const vx = ( x / n ) + 0.5;
const vy = ( y / n ) + 0.5;
const vz = ( z / n ) + 0.5;
color.setRGB( vx, vy, vz );
colors.push( color.r * 255, color.g * 255, color.b * 255 );
colors.push( color.r * 255, color.g * 255, color.b * 255 );
colors.push( color.r * 255, color.g * 255, color.b * 255 );
}
const positionAttribute = new THREE.Float32BufferAttribute( positions, 3 );
const normalAttribute = new THREE.Int16BufferAttribute( normals, 3 );
const colorAttribute = new THREE.Uint8BufferAttribute( colors, 3 );
normalAttribute.normalized = true; // this will map the buffer values to 0.0f - +1.0f in the shader
colorAttribute.normalized = true;
geometry.setAttribute( 'position', positionAttribute );
geometry.setAttribute( 'normal', normalAttribute );
geometry.setAttribute( 'color', colorAttribute );
geometry.computeBoundingSphere();
const material = new THREE.MeshPhongMaterial( {
color: 0xaaaaaa, specular: 0xffffff, shininess: 250,
side: THREE.DoubleSide, vertexColors: true
} );
mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
//
renderer = new THREE.WebGLRenderer();
renderer.setPixelRatio( window.devicePixelRatio );
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.outputEncoding = THREE.sRGBEncoding;
container.appendChild( renderer.domElement );
//
stats = new Stats();
container.appendChild( stats.dom );
//
window.addEventListener( 'resize', onWindowResize );
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize( window.innerWidth, window.innerHeight );
}
//
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function render() {
const time = Date.now() * 0.001;
mesh.rotation.x = time * 0.25;
mesh.rotation.y = time * 0.5;
renderer.render( scene, camera );
}
</script>
</body>
</html>