123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251 |
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <title>three.js webgl2 - volume</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="info">
- <a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl2 - volume
- </div>
- <script type="importmap">
- {
- "imports": {
- "three": "../build/three.module.js",
- "three/addons/": "./jsm/"
- }
- }
- </script>
- <script type="module">
- import * as THREE from 'three';
- import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
- import { ImprovedNoise } from 'three/addons/math/ImprovedNoise.js';
- import { GUI } from 'three/addons/libs/lil-gui.module.min.js';
- let renderer, scene, camera;
- let mesh;
- init();
- function init() {
- renderer = new THREE.WebGLRenderer();
- renderer.setPixelRatio( window.devicePixelRatio );
- renderer.setSize( window.innerWidth, window.innerHeight );
- renderer.setAnimationLoop( animate );
- document.body.appendChild( renderer.domElement );
- scene = new THREE.Scene();
- camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 0.1, 100 );
- camera.position.set( 0, 0, 2 );
- new OrbitControls( camera, renderer.domElement );
- // Texture
- const size = 128;
- const data = new Uint8Array( size * size * size );
- let i = 0;
- const perlin = new ImprovedNoise();
- const vector = new THREE.Vector3();
- for ( let z = 0; z < size; z ++ ) {
- for ( let y = 0; y < size; y ++ ) {
- for ( let x = 0; x < size; x ++ ) {
- vector.set( x, y, z ).divideScalar( size );
- const d = perlin.noise( vector.x * 6.5, vector.y * 6.5, vector.z * 6.5 );
- data[ i ++ ] = d * 128 + 128;
- }
- }
- }
- const texture = new THREE.Data3DTexture( data, size, size, size );
- texture.format = THREE.RedFormat;
- texture.minFilter = THREE.LinearFilter;
- texture.magFilter = THREE.LinearFilter;
- texture.unpackAlignment = 1;
- texture.needsUpdate = true;
- // Material
- const vertexShader = /* glsl */`
- in vec3 position;
- uniform mat4 modelMatrix;
- uniform mat4 modelViewMatrix;
- uniform mat4 projectionMatrix;
- uniform vec3 cameraPos;
- out vec3 vOrigin;
- out vec3 vDirection;
- void main() {
- vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );
- vOrigin = vec3( inverse( modelMatrix ) * vec4( cameraPos, 1.0 ) ).xyz;
- vDirection = position - vOrigin;
- gl_Position = projectionMatrix * mvPosition;
- }
- `;
- const fragmentShader = /* glsl */`
- precision highp float;
- precision highp sampler3D;
- uniform mat4 modelViewMatrix;
- uniform mat4 projectionMatrix;
- in vec3 vOrigin;
- in vec3 vDirection;
- out vec4 color;
- uniform sampler3D map;
- uniform float threshold;
- uniform float steps;
- vec2 hitBox( vec3 orig, vec3 dir ) {
- const vec3 box_min = vec3( - 0.5 );
- const vec3 box_max = vec3( 0.5 );
- vec3 inv_dir = 1.0 / dir;
- vec3 tmin_tmp = ( box_min - orig ) * inv_dir;
- vec3 tmax_tmp = ( box_max - orig ) * inv_dir;
- vec3 tmin = min( tmin_tmp, tmax_tmp );
- vec3 tmax = max( tmin_tmp, tmax_tmp );
- float t0 = max( tmin.x, max( tmin.y, tmin.z ) );
- float t1 = min( tmax.x, min( tmax.y, tmax.z ) );
- return vec2( t0, t1 );
- }
- float sample1( vec3 p ) {
- return texture( map, p ).r;
- }
- #define epsilon .0001
- vec3 normal( vec3 coord ) {
- if ( coord.x < epsilon ) return vec3( 1.0, 0.0, 0.0 );
- if ( coord.y < epsilon ) return vec3( 0.0, 1.0, 0.0 );
- if ( coord.z < epsilon ) return vec3( 0.0, 0.0, 1.0 );
- if ( coord.x > 1.0 - epsilon ) return vec3( - 1.0, 0.0, 0.0 );
- if ( coord.y > 1.0 - epsilon ) return vec3( 0.0, - 1.0, 0.0 );
- if ( coord.z > 1.0 - epsilon ) return vec3( 0.0, 0.0, - 1.0 );
- float step = 0.01;
- float x = sample1( coord + vec3( - step, 0.0, 0.0 ) ) - sample1( coord + vec3( step, 0.0, 0.0 ) );
- float y = sample1( coord + vec3( 0.0, - step, 0.0 ) ) - sample1( coord + vec3( 0.0, step, 0.0 ) );
- float z = sample1( coord + vec3( 0.0, 0.0, - step ) ) - sample1( coord + vec3( 0.0, 0.0, step ) );
- return normalize( vec3( x, y, z ) );
- }
- void main(){
- vec3 rayDir = normalize( vDirection );
- vec2 bounds = hitBox( vOrigin, rayDir );
- if ( bounds.x > bounds.y ) discard;
- bounds.x = max( bounds.x, 0.0 );
- vec3 p = vOrigin + bounds.x * rayDir;
- vec3 inc = 1.0 / abs( rayDir );
- float delta = min( inc.x, min( inc.y, inc.z ) );
- delta /= steps;
- for ( float t = bounds.x; t < bounds.y; t += delta ) {
- float d = sample1( p + 0.5 );
- if ( d > threshold ) {
- color.rgb = normal( p + 0.5 ) * 0.5 + ( p * 1.5 + 0.25 );
- color.a = 1.;
- break;
- }
- p += rayDir * delta;
- }
- if ( color.a == 0.0 ) discard;
- }
- `;
- const geometry = new THREE.BoxGeometry( 1, 1, 1 );
- const material = new THREE.RawShaderMaterial( {
- glslVersion: THREE.GLSL3,
- uniforms: {
- map: { value: texture },
- cameraPos: { value: new THREE.Vector3() },
- threshold: { value: 0.6 },
- steps: { value: 200 }
- },
- vertexShader,
- fragmentShader,
- side: THREE.BackSide,
- } );
- mesh = new THREE.Mesh( geometry, material );
- scene.add( mesh );
- //
- const parameters = { threshold: 0.6, steps: 200 };
- function update() {
- material.uniforms.threshold.value = parameters.threshold;
- material.uniforms.steps.value = parameters.steps;
- }
- const gui = new GUI();
- gui.add( parameters, 'threshold', 0, 1, 0.01 ).onChange( update );
- gui.add( parameters, 'steps', 0, 300, 1 ).onChange( update );
- window.addEventListener( 'resize', onWindowResize );
- }
- function onWindowResize() {
- camera.aspect = window.innerWidth / window.innerHeight;
- camera.updateProjectionMatrix();
- renderer.setSize( window.innerWidth, window.innerHeight );
- }
- function animate() {
- mesh.material.uniforms.cameraPos.value.copy( camera.position );
- renderer.render( scene, camera );
- }
- </script>
- </body>
- </html>
|