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webgl_buffergeometry_points_interleaved.html 4.0 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - buffergeometry - particles</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="container"></div>
  11. <div id="info"><a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> webgl - buffergeometry - particles</div>
  12. <!-- Import maps polyfill -->
  13. <!-- Remove this when import maps will be widely supported -->
  14. <script async src="https://unpkg.com/[email protected]/dist/es-module-shims.js"></script>
  15. <script type="importmap">
  16. {
  17. "imports": {
  18. "three": "../build/three.module.js"
  19. }
  20. }
  21. </script>
  22. <script type="module">
  23. import * as THREE from 'three';
  24. import Stats from './jsm/libs/stats.module.js';
  25. let container, stats;
  26. let camera, scene, renderer;
  27. let points;
  28. init();
  29. animate();
  30. function init() {
  31. container = document.getElementById( 'container' );
  32. camera = new THREE.PerspectiveCamera( 27, window.innerWidth / window.innerHeight, 5, 3500 );
  33. camera.position.z = 2750;
  34. scene = new THREE.Scene();
  35. scene.background = new THREE.Color( 0x050505 );
  36. scene.fog = new THREE.Fog( 0x050505, 2000, 3500 );
  37. //
  38. const particles = 500000;
  39. const geometry = new THREE.BufferGeometry();
  40. // create a generic buffer of binary data (a single particle has 16 bytes of data)
  41. const arrayBuffer = new ArrayBuffer( particles * 16 );
  42. // the following typed arrays share the same buffer
  43. const interleavedFloat32Buffer = new Float32Array( arrayBuffer );
  44. const interleavedUint8Buffer = new Uint8Array( arrayBuffer );
  45. //
  46. const color = new THREE.Color();
  47. const n = 1000, n2 = n / 2; // particles spread in the cube
  48. for ( let i = 0; i < interleavedFloat32Buffer.length; i += 4 ) {
  49. // position (first 12 bytes)
  50. const x = Math.random() * n - n2;
  51. const y = Math.random() * n - n2;
  52. const z = Math.random() * n - n2;
  53. interleavedFloat32Buffer[ i + 0 ] = x;
  54. interleavedFloat32Buffer[ i + 1 ] = y;
  55. interleavedFloat32Buffer[ i + 2 ] = z;
  56. // color (last 4 bytes)
  57. const vx = ( x / n ) + 0.5;
  58. const vy = ( y / n ) + 0.5;
  59. const vz = ( z / n ) + 0.5;
  60. color.setRGB( vx, vy, vz );
  61. const j = ( i + 3 ) * 4;
  62. interleavedUint8Buffer[ j + 0 ] = color.r * 255;
  63. interleavedUint8Buffer[ j + 1 ] = color.g * 255;
  64. interleavedUint8Buffer[ j + 2 ] = color.b * 255;
  65. interleavedUint8Buffer[ j + 3 ] = 0; // not needed
  66. }
  67. const interleavedBuffer32 = new THREE.InterleavedBuffer( interleavedFloat32Buffer, 4 );
  68. const interleavedBuffer8 = new THREE.InterleavedBuffer( interleavedUint8Buffer, 16 );
  69. geometry.setAttribute( 'position', new THREE.InterleavedBufferAttribute( interleavedBuffer32, 3, 0, false ) );
  70. geometry.setAttribute( 'color', new THREE.InterleavedBufferAttribute( interleavedBuffer8, 3, 12, true ) );
  71. //
  72. const material = new THREE.PointsMaterial( { size: 15, vertexColors: true } );
  73. points = new THREE.Points( geometry, material );
  74. scene.add( points );
  75. //
  76. renderer = new THREE.WebGLRenderer();
  77. renderer.setPixelRatio( window.devicePixelRatio );
  78. renderer.setSize( window.innerWidth, window.innerHeight );
  79. container.appendChild( renderer.domElement );
  80. //
  81. stats = new Stats();
  82. container.appendChild( stats.dom );
  83. //
  84. window.addEventListener( 'resize', onWindowResize );
  85. }
  86. function onWindowResize() {
  87. camera.aspect = window.innerWidth / window.innerHeight;
  88. camera.updateProjectionMatrix();
  89. renderer.setSize( window.innerWidth, window.innerHeight );
  90. }
  91. //
  92. function animate() {
  93. requestAnimationFrame( animate );
  94. render();
  95. stats.update();
  96. }
  97. function render() {
  98. const time = Date.now() * 0.001;
  99. points.rotation.x = time * 0.25;
  100. points.rotation.y = time * 0.5;
  101. renderer.render( scene, camera );
  102. }
  103. </script>
  104. </body>
  105. </html>