webgl_materials_texture_partialupdate.html 3.4 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - texture - partial update</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="info">
  11. <a href="https://threejs.org" target="_blank" rel="noopener noreferrer">three.js</a> - partial texture update <br/>
  12. replace parts of an existing texture with all data of another texture
  13. </div>
  14. <script type="importmap">
  15. {
  16. "imports": {
  17. "three": "../build/three.module.js",
  18. "three/addons/": "./jsm/"
  19. }
  20. }
  21. </script>
  22. <script type="module">
  23. import * as THREE from 'three';
  24. let camera, scene, renderer, clock, dataTexture, diffuseMap;
  25. let last = 0;
  26. const position = new THREE.Vector2();
  27. const color = new THREE.Color();
  28. init();
  29. async function init() {
  30. camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 0.01, 10 );
  31. camera.position.z = 2;
  32. scene = new THREE.Scene();
  33. clock = new THREE.Clock();
  34. const loader = new THREE.TextureLoader();
  35. diffuseMap = await loader.loadAsync( 'textures/floors/FloorsCheckerboard_S_Diffuse.jpg' );
  36. diffuseMap.colorSpace = THREE.SRGBColorSpace;
  37. diffuseMap.minFilter = THREE.LinearFilter;
  38. diffuseMap.generateMipmaps = false;
  39. const geometry = new THREE.PlaneGeometry( 2, 2 );
  40. const material = new THREE.MeshBasicMaterial( { map: diffuseMap } );
  41. const mesh = new THREE.Mesh( geometry, material );
  42. scene.add( mesh );
  43. //
  44. const width = 32;
  45. const height = 32;
  46. const data = new Uint8Array( width * height * 4 );
  47. dataTexture = new THREE.DataTexture( data, width, height );
  48. //
  49. renderer = new THREE.WebGLRenderer( { antialias: true } );
  50. renderer.setPixelRatio( window.devicePixelRatio );
  51. renderer.setSize( window.innerWidth, window.innerHeight );
  52. renderer.setAnimationLoop( animate );
  53. document.body.appendChild( renderer.domElement );
  54. //
  55. window.addEventListener( 'resize', onWindowResize );
  56. }
  57. function onWindowResize() {
  58. camera.aspect = window.innerWidth / window.innerHeight;
  59. camera.updateProjectionMatrix();
  60. renderer.setSize( window.innerWidth, window.innerHeight );
  61. }
  62. function animate() {
  63. const elapsedTime = clock.getElapsedTime();
  64. if ( elapsedTime - last > 0.1 ) {
  65. last = elapsedTime;
  66. position.x = ( 32 * THREE.MathUtils.randInt( 1, 16 ) ) - 32;
  67. position.y = ( 32 * THREE.MathUtils.randInt( 1, 16 ) ) - 32;
  68. // generate new color data
  69. updateDataTexture( dataTexture );
  70. // perform copy from src to dest texture to a random position
  71. renderer.copyTextureToTexture( dataTexture, diffuseMap, null, position );
  72. }
  73. renderer.render( scene, camera );
  74. }
  75. function updateDataTexture( texture ) {
  76. const size = texture.image.width * texture.image.height;
  77. const data = texture.image.data;
  78. // generate a random color and update texture data
  79. color.setHex( Math.random() * 0xffffff );
  80. const r = Math.floor( color.r * 255 );
  81. const g = Math.floor( color.g * 255 );
  82. const b = Math.floor( color.b * 255 );
  83. for ( let i = 0; i < size; i ++ ) {
  84. const stride = i * 4;
  85. data[ stride ] = r;
  86. data[ stride + 1 ] = g;
  87. data[ stride + 2 ] = b;
  88. data[ stride + 3 ] = 1;
  89. }
  90. }
  91. </script>
  92. </body>
  93. </html>