webgl_geometry_colors_lookuptable.html 4.6 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212
  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - lookup table</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. <style>
  9. body {
  10. background-color: #fff;
  11. color: #444;
  12. }
  13. a {
  14. color: red;
  15. }
  16. </style>
  17. </head>
  18. <body>
  19. <div id="info">
  20. <a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl - lookup table<br/>
  21. vertex color values from a range of data values
  22. </div>
  23. <div id="container"></div>
  24. <!-- Import maps polyfill -->
  25. <!-- Remove this when import maps will be widely supported -->
  26. <script async src="https://unpkg.com/[email protected]/dist/es-module-shims.js"></script>
  27. <script type="importmap">
  28. {
  29. "imports": {
  30. "three": "../build/three.module.js"
  31. }
  32. }
  33. </script>
  34. <script type="module">
  35. import * as THREE from 'three';
  36. import { GUI } from './jsm/libs/lil-gui.module.min.js';
  37. import { OrbitControls } from './jsm/controls/OrbitControls.js';
  38. import { Lut } from './jsm/math/Lut.js';
  39. let container;
  40. let perpCamera, orthoCamera, renderer, lut;
  41. let mesh, sprite;
  42. let scene, uiScene;
  43. let params;
  44. init();
  45. function init() {
  46. container = document.getElementById( 'container' );
  47. scene = new THREE.Scene();
  48. scene.background = new THREE.Color( 0xffffff );
  49. uiScene = new THREE.Scene();
  50. lut = new Lut();
  51. const width = window.innerWidth;
  52. const height = window.innerHeight;
  53. perpCamera = new THREE.PerspectiveCamera( 60, width / height, 1, 100 );
  54. perpCamera.position.set( 0, 0, 10 );
  55. scene.add( perpCamera );
  56. orthoCamera = new THREE.OrthographicCamera( - 1, 1, 1, - 1, 1, 2 );
  57. orthoCamera.position.set( 0.5, 0, 1 );
  58. sprite = new THREE.Sprite( new THREE.SpriteMaterial( {
  59. map: new THREE.CanvasTexture( lut.createCanvas() )
  60. } ) );
  61. sprite.scale.x = 0.125;
  62. uiScene.add( sprite );
  63. mesh = new THREE.Mesh( undefined, new THREE.MeshLambertMaterial( {
  64. side: THREE.DoubleSide,
  65. color: 0xF5F5F5,
  66. vertexColors: true
  67. } ) );
  68. scene.add( mesh );
  69. params = {
  70. colorMap: 'rainbow',
  71. };
  72. loadModel( );
  73. const pointLight = new THREE.PointLight( 0xffffff, 1 );
  74. perpCamera.add( pointLight );
  75. renderer = new THREE.WebGLRenderer( { antialias: true } );
  76. renderer.autoClear = false;
  77. renderer.setPixelRatio( window.devicePixelRatio );
  78. renderer.setSize( width, height );
  79. container.appendChild( renderer.domElement );
  80. window.addEventListener( 'resize', onWindowResize );
  81. const controls = new OrbitControls( perpCamera, renderer.domElement );
  82. controls.addEventListener( 'change', render );
  83. const gui = new GUI();
  84. gui.add( params, 'colorMap', [ 'rainbow', 'cooltowarm', 'blackbody', 'grayscale' ] ).onChange( function () {
  85. updateColors();
  86. render();
  87. } );
  88. }
  89. function onWindowResize() {
  90. const width = window.innerWidth;
  91. const height = window.innerHeight;
  92. perpCamera.aspect = width / height;
  93. perpCamera.updateProjectionMatrix();
  94. renderer.setSize( width, height );
  95. render();
  96. }
  97. function render() {
  98. renderer.clear();
  99. renderer.render( scene, perpCamera );
  100. renderer.render( uiScene, orthoCamera );
  101. }
  102. function loadModel( ) {
  103. const loader = new THREE.BufferGeometryLoader();
  104. loader.load( 'models/json/pressure.json', function ( geometry ) {
  105. geometry.center();
  106. geometry.computeVertexNormals();
  107. // default color attribute
  108. const colors = [];
  109. for ( let i = 0, n = geometry.attributes.position.count; i < n; ++ i ) {
  110. colors.push( 1, 1, 1 );
  111. }
  112. geometry.setAttribute( 'color', new THREE.Float32BufferAttribute( colors, 3 ) );
  113. mesh.geometry = geometry;
  114. updateColors();
  115. render();
  116. } );
  117. }
  118. function updateColors() {
  119. lut.setColorMap( params.colorMap );
  120. lut.setMax( 2000 );
  121. lut.setMin( 0 );
  122. const geometry = mesh.geometry;
  123. const pressures = geometry.attributes.pressure;
  124. const colors = geometry.attributes.color;
  125. for ( let i = 0; i < pressures.array.length; i ++ ) {
  126. const colorValue = pressures.array[ i ];
  127. const color = lut.getColor( colorValue );
  128. if ( color === undefined ) {
  129. console.log( 'Unable to determine color for value:', colorValue );
  130. } else {
  131. colors.setXYZ( i, color.r, color.g, color.b );
  132. }
  133. }
  134. colors.needsUpdate = true;
  135. const map = sprite.material.map;
  136. lut.updateCanvas( map.image );
  137. map.needsUpdate = true;
  138. }
  139. </script>
  140. </body>
  141. </html>