webgl2_volume_cloud.html 7.0 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl2 - volume - cloud</title>
  5. <meta charset="utf-8">
  6. <meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
  7. <link type="text/css" rel="stylesheet" href="main.css">
  8. </head>
  9. <body>
  10. <div id="info">
  11. <a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl2 - volume - cloud
  12. </div>
  13. <script type="module">
  14. import * as THREE from '../build/three.module.js';
  15. import { OrbitControls } from './jsm/controls/OrbitControls.js';
  16. import { ImprovedNoise } from './jsm/math/ImprovedNoise.js';
  17. import { GUI } from './jsm/libs/dat.gui.module.js';
  18. import { WEBGL } from './jsm/WebGL.js';
  19. if ( WEBGL.isWebGL2Available() === false ) {
  20. document.body.appendChild( WEBGL.getWebGL2ErrorMessage() );
  21. }
  22. let renderer, scene, camera;
  23. let mesh;
  24. init();
  25. animate();
  26. function init() {
  27. renderer = new THREE.WebGLRenderer();
  28. renderer.setPixelRatio( window.devicePixelRatio );
  29. renderer.setSize( window.innerWidth, window.innerHeight );
  30. document.body.appendChild( renderer.domElement );
  31. scene = new THREE.Scene();
  32. camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 0.1, 100 );
  33. camera.position.set( 0, 0, 1.5 );
  34. new OrbitControls( camera, renderer.domElement );
  35. // Sky
  36. const canvas = document.createElement( 'canvas' );
  37. canvas.width = 1;
  38. canvas.height = 32;
  39. const context = canvas.getContext( '2d' );
  40. const gradient = context.createLinearGradient( 0, 0, 0, 32 );
  41. gradient.addColorStop( 0.0, '#014a84' );
  42. gradient.addColorStop( 0.5, '#0561a0' );
  43. gradient.addColorStop( 1.0, '#437ab6' );
  44. context.fillStyle = gradient;
  45. context.fillRect( 0, 0, 1, 32 );
  46. const sky = new THREE.Mesh(
  47. new THREE.SphereBufferGeometry( 10 ),
  48. new THREE.MeshBasicMaterial( { map: new THREE.CanvasTexture( canvas ), side: THREE.BackSide } )
  49. );
  50. scene.add( sky );
  51. // Texture
  52. const size = 128;
  53. const data = new Uint8Array( size * size * size );
  54. let i = 0;
  55. const scale = 0.05;
  56. const perlin = new ImprovedNoise();
  57. const vector = new THREE.Vector3();
  58. for ( let z = 0; z < size; z ++ ) {
  59. for ( let y = 0; y < size; y ++ ) {
  60. for ( let x = 0; x < size; x ++ ) {
  61. const d = 1.0 - vector.set( x, y, z ).subScalar( size / 2 ).divideScalar( size ).length();
  62. data[ i ] = ( 128 + 128 * perlin.noise( x * scale / 1.5, y * scale, z * scale / 1.5 ) ) * d * d;
  63. i ++;
  64. }
  65. }
  66. }
  67. const texture = new THREE.DataTexture3D( data, size, size, size );
  68. texture.format = THREE.RedFormat;
  69. texture.minFilter = THREE.LinearFilter;
  70. texture.magFilter = THREE.LinearFilter;
  71. texture.unpackAlignment = 1;
  72. // Material
  73. const vertexShader = `#version 300 es
  74. in vec3 position;
  75. uniform mat4 modelMatrix;
  76. uniform mat4 modelViewMatrix;
  77. uniform mat4 projectionMatrix;
  78. uniform vec3 cameraPos;
  79. out vec3 vOrigin;
  80. out vec3 vDirection;
  81. void main() {
  82. vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );
  83. vOrigin = vec3( inverse( modelMatrix ) * vec4( cameraPos, 1.0 ) ).xyz;
  84. vDirection = position - vOrigin;
  85. gl_Position = projectionMatrix * mvPosition;
  86. }
  87. `;
  88. const fragmentShader = `#version 300 es
  89. precision highp float;
  90. precision highp sampler3D;
  91. uniform mat4 modelViewMatrix;
  92. uniform mat4 projectionMatrix;
  93. in vec3 vOrigin;
  94. in vec3 vDirection;
  95. out vec4 color;
  96. uniform vec3 base;
  97. uniform sampler3D map;
  98. uniform float threshold;
  99. uniform float range;
  100. uniform float opacity;
  101. uniform float steps;
  102. vec2 hitBox( vec3 orig, vec3 dir ) {
  103. const vec3 box_min = vec3( - 0.5 );
  104. const vec3 box_max = vec3( 0.5 );
  105. vec3 inv_dir = 1.0 / dir;
  106. vec3 tmin_tmp = ( box_min - orig ) * inv_dir;
  107. vec3 tmax_tmp = ( box_max - orig ) * inv_dir;
  108. vec3 tmin = min( tmin_tmp, tmax_tmp );
  109. vec3 tmax = max( tmin_tmp, tmax_tmp );
  110. float t0 = max( tmin.x, max( tmin.y, tmin.z ) );
  111. float t1 = min( tmax.x, min( tmax.y, tmax.z ) );
  112. return vec2( t0, t1 );
  113. }
  114. float sample1( vec3 p ) {
  115. return texture( map, p ).r;
  116. }
  117. float shading( vec3 coord ) {
  118. float step = 0.01;
  119. return sample1( coord + vec3( - step ) ) - sample1( coord + vec3( step ) );
  120. }
  121. void main(){
  122. vec3 rayDir = normalize( vDirection );
  123. vec2 bounds = hitBox( vOrigin, rayDir );
  124. if ( bounds.x > bounds.y ) discard;
  125. bounds.x = max( bounds.x, 0.0 );
  126. vec3 p = vOrigin + bounds.x * rayDir;
  127. vec3 inc = 1.0 / abs( rayDir );
  128. float delta = min( inc.x, min( inc.y, inc.z ) );
  129. delta /= steps;
  130. vec4 ac = vec4( base, 0.0 );
  131. for ( float t = bounds.x; t < bounds.y; t += delta ) {
  132. float d = sample1( p + 0.5 );
  133. d = smoothstep( threshold - range, threshold + range, d ) * opacity;
  134. float col = shading( p + 0.5 ) * 3.0 + ( ( p.x + p.y ) * 0.25 ) + 0.2;
  135. ac.rgb += ( 1.0 - ac.a ) * d * col;
  136. ac.a += ( 1.0 - ac.a ) * d;
  137. if ( ac.a >= 0.95 ) break;
  138. p += rayDir * delta;
  139. }
  140. color = ac;
  141. if ( color.a == 0.0 ) discard;
  142. }
  143. `;
  144. const geometry = new THREE.BoxBufferGeometry( 1, 1, 1 );
  145. const material = new THREE.RawShaderMaterial( {
  146. uniforms: {
  147. base: { value: new THREE.Color( 0x798aa0 ) },
  148. map: { value: texture },
  149. cameraPos: { value: new THREE.Vector3() },
  150. threshold: { value: 0.25 },
  151. opacity: { value: 0.25 },
  152. range: { value: 0.1 },
  153. steps: { value: 100 }
  154. },
  155. vertexShader,
  156. fragmentShader,
  157. side: THREE.BackSide,
  158. transparent: true
  159. } );
  160. mesh = new THREE.Mesh( geometry, material );
  161. scene.add( mesh );
  162. //
  163. const parameters = { threshold: 0.25, opacity: 0.25, range: 0.1, steps: 100 };
  164. function update() {
  165. material.uniforms.threshold.value = parameters.threshold;
  166. material.uniforms.opacity.value = parameters.opacity;
  167. material.uniforms.range.value = parameters.range;
  168. material.uniforms.steps.value = parameters.steps;
  169. }
  170. const gui = new GUI();
  171. gui.add( parameters, 'threshold', 0, 1, 0.01 ).onChange( update );
  172. gui.add( parameters, 'opacity', 0, 1, 0.01 ).onChange( update );
  173. gui.add( parameters, 'range', 0, 1, 0.01 ).onChange( update );
  174. gui.add( parameters, 'steps', 0, 200, 1 ).onChange( update );
  175. window.addEventListener( 'resize', onWindowResize, false );
  176. }
  177. function onWindowResize() {
  178. camera.aspect = window.innerWidth / window.innerHeight;
  179. camera.updateProjectionMatrix();
  180. renderer.setSize( window.innerWidth, window.innerHeight );
  181. }
  182. function animate() {
  183. requestAnimationFrame( animate );
  184. mesh.material.uniforms.cameraPos.value.copy( camera.position );
  185. mesh.rotation.y = - performance.now() / 7500;
  186. renderer.render( scene, camera );
  187. }
  188. </script>
  189. </body>
  190. </html>