webvr_lorenzattractor.html 4.1 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webvr - lorenz attractor</title>
  5. <meta charset="utf-8">
  6. <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
  7. <link type="text/css" rel="stylesheet" href="main.css">
  8. <!-- WebXR Device API (For Chrome M76+), expires 09/09/2019 -->
  9. <meta http-equiv="origin-trial" content="Ai1/G787sugfmWtk1xQExa8N6OqwDsJyNn+OwpA1J4PozR1lixRYIQ4Tmp00vrGWS8FQQ2iDyqjwaewrOfYvPAUAAABTeyJvcmlnaW4iOiJodHRwczovL3RocmVlanMub3JnOjQ0MyIsImZlYXR1cmUiOiJXZWJYUkRldmljZU03NiIsImV4cGlyeSI6MTU2ODAyMzQ3OH0=">
  10. </head>
  11. <body>
  12. <script src="js/vr/HelioWebXRPolyfill.js"></script>
  13. <script type="module">
  14. import * as THREE from '../build/three.module.js';
  15. import { WEBVR } from './jsm/vr/WebVR.js';
  16. var camera, scene, renderer;
  17. var attractor, light;
  18. var x = 15 * Math.random();
  19. var y = 15 * Math.random();
  20. var z = 15 * Math.random();
  21. var scale = .02; // for reducing overall displayed size
  22. var speed = 5; // integer, increase for faster visualization
  23. var steps = 100000;
  24. var current = 1;
  25. var shown = 10000;
  26. var beta = 8 / 3;
  27. var rho = 28;
  28. var sigma = 10;
  29. var dt = .005;
  30. init();
  31. animate();
  32. function draw() {
  33. var geometry = attractor.geometry;
  34. geometry.attributes.position.array.copyWithin( 3 );
  35. geometry.attributes.color.array.copyWithin( 3 );
  36. if ( current < steps ) {
  37. var dx = sigma * ( y - x ) * dt;
  38. var dy = ( x * ( rho - z ) - y ) * dt;
  39. var dz = ( x * y - beta * z ) * dt;
  40. x += dx;
  41. y += dy;
  42. z += dz;
  43. geometry.attributes.position.set( [ scale * x, scale * y, scale * z ], 0 );
  44. light.color.setHSL( current / steps, 1, .5 );
  45. geometry.attributes.color.set( light.color.toArray(), 0 );
  46. }
  47. if ( current < steps + shown ) {
  48. current ++;
  49. } else {
  50. current = 0;
  51. }
  52. }
  53. function init() {
  54. scene = new THREE.Scene();
  55. camera = new THREE.PerspectiveCamera( 50, window.innerWidth / window.innerHeight, 0.1, 10 );
  56. //
  57. var geometry = new THREE.BufferGeometry();
  58. var positions = new Float32Array( 3 * shown );
  59. for ( var i = 0; i < positions.length; i += 3 ) {
  60. positions.set( [ scale * x, scale * y, scale * z ], i );
  61. }
  62. geometry.addAttribute( 'position', new THREE.BufferAttribute( positions, 3 ) );
  63. var colors = new Float32Array( 3 * shown );
  64. for ( var i = 0; i < positions.length; i += 3 ) {
  65. colors.set( [ 1, 0, 0 ], i );
  66. }
  67. geometry.addAttribute( 'color', new THREE.BufferAttribute( colors, 3 ) );
  68. var material = new THREE.LineBasicMaterial( { vertexColors: THREE.VertexColors } );
  69. attractor = new THREE.Line( geometry, material );
  70. attractor.position.set( 0, 1.5, - 2 );
  71. attractor.frustumCulled = false; // critical to avoid blackouts!
  72. scene.add( attractor );
  73. //
  74. light = new THREE.PointLight( 0xffffff, 1 );
  75. light.distance = 2;
  76. attractor.add( light );
  77. var ground = new THREE.Mesh(
  78. new THREE.PlaneBufferGeometry( 10, 10 ),
  79. new THREE.MeshPhongMaterial()
  80. );
  81. ground.geometry.rotateX( - 90 * Math.PI / 180 );
  82. scene.add( ground );
  83. //
  84. renderer = new THREE.WebGLRenderer( { antialias: true } );
  85. renderer.setPixelRatio( window.devicePixelRatio );
  86. renderer.setSize( window.innerWidth, window.innerHeight );
  87. renderer.vr.enabled = true;
  88. document.body.appendChild( renderer.domElement );
  89. document.body.appendChild( WEBVR.createButton( renderer ) );
  90. //
  91. window.addEventListener( 'resize', onWindowResize, false );
  92. }
  93. function onWindowResize() {
  94. camera.aspect = window.innerWidth / window.innerHeight;
  95. camera.updateProjectionMatrix();
  96. renderer.setSize( window.innerWidth, window.innerHeight );
  97. }
  98. function animate() {
  99. renderer.setAnimationLoop( render );
  100. }
  101. function render() {
  102. for ( var i = 0; i < speed; i ++ ) draw();
  103. attractor.geometry.attributes.position.needsUpdate = true;
  104. attractor.geometry.attributes.color.needsUpdate = true;
  105. attractor.rotation.z += .001;
  106. renderer.render( scene, camera );
  107. }
  108. </script>
  109. </body>
  110. </html>