webgl_materials_grass.html 3.2 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - materials - grass</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. <style>
  8. body {
  9. background:#030;
  10. color:#fff;
  11. padding:0;
  12. margin:0;
  13. overflow:hidden;
  14. font-family:georgia;
  15. text-align:center;
  16. }
  17. </style>
  18. </head>
  19. <body>
  20. <script src="../build/three.min.js"></script>
  21. <script src="js/Detector.js"></script>
  22. <script>
  23. if ( ! Detector.webgl ) Detector.addGetWebGLMessage();
  24. var camera, scene, renderer,
  25. mesh, levels = [];
  26. init();
  27. animate();
  28. function init() {
  29. camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 1, 1000 );
  30. camera.position.set( 0, 75, 100 );
  31. scene = new THREE.Scene();
  32. var geometry = new THREE.PlaneGeometry( 100, 100 );
  33. var bitmap = generateTextureBase();
  34. for ( var i = 0; i < 15; i ++ ) {
  35. mesh = levels[ i ] = new THREE.Mesh( geometry, new THREE.MeshBasicMaterial( { map: new THREE.Texture( generateTextureLevel( bitmap ) ), transparent: true, depthWrite: false, depthTest: false } ) );
  36. mesh.material.map.needsUpdate = true;
  37. mesh.position.y = i * 0.25;
  38. mesh.rotation.x = - Math.PI / 2;
  39. scene.add( mesh );
  40. }
  41. renderer = new THREE.WebGLRenderer();
  42. renderer.sortObjects = false;
  43. renderer.setSize( window.innerWidth, window.innerHeight );
  44. document.body.appendChild( renderer.domElement );
  45. //
  46. window.addEventListener( 'resize', onWindowResize, false );
  47. }
  48. function onWindowResize() {
  49. camera.aspect = window.innerWidth / window.innerHeight;
  50. camera.updateProjectionMatrix();
  51. renderer.setSize( window.innerWidth, window.innerHeight );
  52. }
  53. function generateTextureBase() {
  54. var canvas = document.createElement( 'canvas' );
  55. canvas.width = 512;
  56. canvas.height = 512;
  57. var context = canvas.getContext( '2d' );
  58. for ( var i = 0; i < 20000; i ++ ) {
  59. context.fillStyle = 'rgba(0,' + Math.floor( Math.random() * 64 + 32 ) + ',16,1)';
  60. context.beginPath();
  61. context.arc( Math.random() * canvas.width, Math.random() * canvas.height, Math.random() * 1 + 0.5, 0, Math.PI * 2, true );
  62. context.fill();
  63. }
  64. context.globalAlpha = 0.075;
  65. context.globalCompositeOperation = 'lighter';
  66. return canvas;
  67. }
  68. function generateTextureLevel( texture ) {
  69. texture.getContext( '2d' ).drawImage( texture, 0, 0 );
  70. var canvas = document.createElement( 'canvas' );
  71. canvas.width = texture.width;
  72. canvas.height = texture.height;
  73. canvas.getContext( '2d' ).drawImage( texture, 0, 0 );
  74. return canvas;
  75. }
  76. //
  77. function animate() {
  78. requestAnimationFrame( animate );
  79. render();
  80. }
  81. function render() {
  82. var time = Date.now() / 6000;
  83. camera.position.x = 80 * Math.cos( time );
  84. camera.position.z = 80 * Math.sin( time );
  85. camera.lookAt( scene.position );
  86. for ( var i = 0, l = levels.length; i < l; i ++ ) {
  87. mesh = levels[ i ];
  88. mesh.position.x = Math.sin( time * 4 ) * i * i * 0.005;
  89. mesh.position.z = Math.cos( time * 6 ) * i * i * 0.005;
  90. }
  91. renderer.render( scene, camera );
  92. }
  93. </script>
  94. </body>
  95. </html>