canvas-textured-cube.html 3.0 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. <script type="importmap">
  24. {
  25. "imports": {
  26. "three": "../../build/three.module.js"
  27. }
  28. }
  29. </script>
  30. <script type="module">
  31. import * as THREE from 'three';
  32. function main() {
  33. const canvas = document.querySelector( '#c' );
  34. const renderer = new THREE.WebGLRenderer( { antialias: true, canvas } );
  35. const fov = 75;
  36. const aspect = 2; // the canvas default
  37. const near = 0.1;
  38. const far = 5;
  39. const camera = new THREE.PerspectiveCamera( fov, aspect, near, far );
  40. camera.position.z = 2;
  41. const scene = new THREE.Scene();
  42. const boxWidth = 1;
  43. const boxHeight = 1;
  44. const boxDepth = 1;
  45. const geometry = new THREE.BoxGeometry( boxWidth, boxHeight, boxDepth );
  46. const cubes = []; // just an array we can use to rotate the cubes
  47. const ctx = document.createElement( 'canvas' ).getContext( '2d' );
  48. ctx.canvas.width = 256;
  49. ctx.canvas.height = 256;
  50. ctx.fillStyle = '#FFF';
  51. ctx.fillRect( 0, 0, ctx.canvas.width, ctx.canvas.height );
  52. const texture = new THREE.CanvasTexture( ctx.canvas );
  53. const material = new THREE.MeshBasicMaterial( {
  54. map: texture,
  55. } );
  56. const cube = new THREE.Mesh( geometry, material );
  57. scene.add( cube );
  58. cubes.push( cube ); // add to our list of cubes to rotate
  59. function resizeRendererToDisplaySize( renderer ) {
  60. const canvas = renderer.domElement;
  61. const width = canvas.clientWidth;
  62. const height = canvas.clientHeight;
  63. const needResize = canvas.width !== width || canvas.height !== height;
  64. if ( needResize ) {
  65. renderer.setSize( width, height, false );
  66. }
  67. return needResize;
  68. }
  69. function randInt( min, max ) {
  70. if ( max === undefined ) {
  71. max = min;
  72. min = 0;
  73. }
  74. return Math.random() * ( max - min ) + min | 0;
  75. }
  76. function drawRandomDot() {
  77. ctx.fillStyle = `#${randInt( 0x1000000 ).toString( 16 ).padStart( 6, '0' )}`;
  78. ctx.beginPath();
  79. const x = randInt( 256 );
  80. const y = randInt( 256 );
  81. const radius = randInt( 10, 64 );
  82. ctx.arc( x, y, radius, 0, Math.PI * 2 );
  83. ctx.fill();
  84. }
  85. function render( time ) {
  86. time *= 0.001;
  87. if ( resizeRendererToDisplaySize( renderer ) ) {
  88. const canvas = renderer.domElement;
  89. camera.aspect = canvas.clientWidth / canvas.clientHeight;
  90. camera.updateProjectionMatrix();
  91. }
  92. drawRandomDot();
  93. texture.needsUpdate = true;
  94. cubes.forEach( ( cube, ndx ) => {
  95. const speed = .2 + ndx * .1;
  96. const rot = time * speed;
  97. cube.rotation.x = rot;
  98. cube.rotation.y = rot;
  99. } );
  100. renderer.render( scene, camera );
  101. requestAnimationFrame( render );
  102. }
  103. requestAnimationFrame( render );
  104. }
  105. main();
  106. </script>
  107. </html>