threejs-render-target.html 3.6 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148
  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 - Responsive</title>
  8. <style>
  9. body {
  10. margin: 0;
  11. }
  12. #c {
  13. width: 100vw;
  14. height: 100vh;
  15. display: block;
  16. }
  17. </style>
  18. </head>
  19. <body>
  20. <canvas id="c"></canvas>
  21. </body>
  22. <script src="resources/threejs/r102/three.min.js"></script>
  23. <script>
  24. 'use strict';
  25. /* global THREE */
  26. function main() {
  27. const canvas = document.querySelector('#c');
  28. const renderer = new THREE.WebGLRenderer({canvas: canvas});
  29. const rtWidth = 512;
  30. const rtHeight = 512;
  31. const renderTarget = new THREE.WebGLRenderTarget(rtWidth, rtHeight);
  32. const rtFov = 75;
  33. const rtAspect = rtWidth / rtHeight;
  34. const rtNear = 0.1;
  35. const rtFar = 5;
  36. const rtCamera = new THREE.PerspectiveCamera(rtFov, rtAspect, rtNear, rtFar);
  37. rtCamera.position.z = 2;
  38. const rtScene = new THREE.Scene();
  39. rtScene.background = new THREE.Color('red');
  40. {
  41. const color = 0xFFFFFF;
  42. const intensity = 1;
  43. const light = new THREE.DirectionalLight(color, intensity);
  44. light.position.set(-1, 2, 4);
  45. rtScene.add(light);
  46. }
  47. const boxWidth = 1;
  48. const boxHeight = 1;
  49. const boxDepth = 1;
  50. const geometry = new THREE.BoxGeometry(boxWidth, boxHeight, boxDepth);
  51. function makeInstance(geometry, color, x) {
  52. const material = new THREE.MeshPhongMaterial({color});
  53. const cube = new THREE.Mesh(geometry, material);
  54. rtScene.add(cube);
  55. cube.position.x = x;
  56. return cube;
  57. }
  58. const rtCubes = [
  59. makeInstance(geometry, 0x44aa88, 0),
  60. makeInstance(geometry, 0x8844aa, -2),
  61. makeInstance(geometry, 0xaa8844, 2),
  62. ];
  63. const fov = 75;
  64. const aspect = 2; // the canvas default
  65. const near = 0.1;
  66. const far = 5;
  67. const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
  68. camera.position.z = 2;
  69. const scene = new THREE.Scene();
  70. {
  71. const color = 0xFFFFFF;
  72. const intensity = 1;
  73. const light = new THREE.DirectionalLight(color, intensity);
  74. light.position.set(-1, 2, 4);
  75. scene.add(light);
  76. }
  77. const material = new THREE.MeshPhongMaterial({
  78. map: renderTarget.texture,
  79. });
  80. const cube = new THREE.Mesh(geometry, material);
  81. scene.add(cube);
  82. function resizeRendererToDisplaySize(renderer) {
  83. const canvas = renderer.domElement;
  84. const width = canvas.clientWidth;
  85. const height = canvas.clientHeight;
  86. const needResize = canvas.width !== width || canvas.height !== height;
  87. if (needResize) {
  88. renderer.setSize(width, height, false);
  89. }
  90. return needResize;
  91. }
  92. function render(time) {
  93. time *= 0.001;
  94. if (resizeRendererToDisplaySize(renderer)) {
  95. const canvas = renderer.domElement;
  96. camera.aspect = canvas.clientWidth / canvas.clientHeight;
  97. camera.updateProjectionMatrix();
  98. }
  99. // rotate all the cubes in the render target scene
  100. rtCubes.forEach((cube, ndx) => {
  101. const speed = 1 + ndx * .1;
  102. const rot = time * speed;
  103. cube.rotation.x = rot;
  104. cube.rotation.y = rot;
  105. });
  106. // draw render target scene to render target
  107. renderer.setRenderTarget(renderTarget);
  108. renderer.render(rtScene, rtCamera);
  109. renderer.setRenderTarget(null);
  110. // rotate the cube in the scene
  111. cube.rotation.x = time;
  112. cube.rotation.y = time * 1.1;
  113. // render the scene to the canvas
  114. renderer.render(scene, camera);
  115. requestAnimationFrame(render);
  116. }
  117. requestAnimationFrame(render);
  118. }
  119. main();
  120. </script>
  121. </html>