canvas-textured-cube.html 3.2 KB

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  1. <!-- Licensed under a BSD license. See license.html for license -->
  2. <!DOCTYPE html>
  3. <html>
  4. <head>
  5. <meta charset="utf-8">
  6. <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
  7. <title>Three.js - Canvas Textured Cube</title>
  8. <style>
  9. html, body {
  10. height: 100%;
  11. margin: 0;
  12. }
  13. #c {
  14. width: 100%;
  15. height: 100%;
  16. display: block;
  17. }
  18. </style>
  19. </head>
  20. <body>
  21. <canvas id="c"></canvas>
  22. </body>
  23. <!-- Import maps polyfill -->
  24. <!-- Remove this when import maps will be widely supported -->
  25. <script async src="https://unpkg.com/[email protected]/dist/es-module-shims.js"></script>
  26. <script type="importmap">
  27. {
  28. "imports": {
  29. "three": "../../build/three.module.js"
  30. }
  31. }
  32. </script>
  33. <script type="module">
  34. import * as THREE from 'three';
  35. function main() {
  36. const canvas = document.querySelector( '#c' );
  37. const renderer = new THREE.WebGLRenderer( { antialias: true, canvas } );
  38. const fov = 75;
  39. const aspect = 2; // the canvas default
  40. const near = 0.1;
  41. const far = 5;
  42. const camera = new THREE.PerspectiveCamera( fov, aspect, near, far );
  43. camera.position.z = 2;
  44. const scene = new THREE.Scene();
  45. const boxWidth = 1;
  46. const boxHeight = 1;
  47. const boxDepth = 1;
  48. const geometry = new THREE.BoxGeometry( boxWidth, boxHeight, boxDepth );
  49. const cubes = []; // just an array we can use to rotate the cubes
  50. const ctx = document.createElement( 'canvas' ).getContext( '2d' );
  51. ctx.canvas.width = 256;
  52. ctx.canvas.height = 256;
  53. ctx.fillStyle = '#FFF';
  54. ctx.fillRect( 0, 0, ctx.canvas.width, ctx.canvas.height );
  55. const texture = new THREE.CanvasTexture( ctx.canvas );
  56. const material = new THREE.MeshBasicMaterial( {
  57. map: texture,
  58. } );
  59. const cube = new THREE.Mesh( geometry, material );
  60. scene.add( cube );
  61. cubes.push( cube ); // add to our list of cubes to rotate
  62. function resizeRendererToDisplaySize( renderer ) {
  63. const canvas = renderer.domElement;
  64. const width = canvas.clientWidth;
  65. const height = canvas.clientHeight;
  66. const needResize = canvas.width !== width || canvas.height !== height;
  67. if ( needResize ) {
  68. renderer.setSize( width, height, false );
  69. }
  70. return needResize;
  71. }
  72. function randInt( min, max ) {
  73. if ( max === undefined ) {
  74. max = min;
  75. min = 0;
  76. }
  77. return Math.random() * ( max - min ) + min | 0;
  78. }
  79. function drawRandomDot() {
  80. ctx.fillStyle = `#${randInt( 0x1000000 ).toString( 16 ).padStart( 6, '0' )}`;
  81. ctx.beginPath();
  82. const x = randInt( 256 );
  83. const y = randInt( 256 );
  84. const radius = randInt( 10, 64 );
  85. ctx.arc( x, y, radius, 0, Math.PI * 2 );
  86. ctx.fill();
  87. }
  88. function render( time ) {
  89. time *= 0.001;
  90. if ( resizeRendererToDisplaySize( renderer ) ) {
  91. const canvas = renderer.domElement;
  92. camera.aspect = canvas.clientWidth / canvas.clientHeight;
  93. camera.updateProjectionMatrix();
  94. }
  95. drawRandomDot();
  96. texture.needsUpdate = true;
  97. cubes.forEach( ( cube, ndx ) => {
  98. const speed = .2 + ndx * .1;
  99. const rot = time * speed;
  100. cube.rotation.x = rot;
  101. cube.rotation.y = rot;
  102. } );
  103. renderer.render( scene, camera );
  104. requestAnimationFrame( render );
  105. }
  106. requestAnimationFrame( render );
  107. }
  108. main();
  109. </script>
  110. </html>