webgl2_volume_instancing.html 6.4 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl2 - volume - instancing</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">three.js</a> webgl2 - volume - instancing
  12. </div>
  13. <!-- Import maps polyfill -->
  14. <!-- Remove this when import maps will be widely supported -->
  15. <script async src="https://unpkg.com/[email protected]/dist/es-module-shims.js"></script>
  16. <script type="importmap">
  17. {
  18. "imports": {
  19. "three": "../build/three.module.js",
  20. "three/addons/": "./jsm/"
  21. }
  22. }
  23. </script>
  24. <script type="module">
  25. import * as THREE from 'three';
  26. import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
  27. import { VOXLoader, VOXData3DTexture } from 'three/addons/loaders/VOXLoader.js';
  28. import WebGL from 'three/addons/capabilities/WebGL.js';
  29. if ( WebGL.isWebGL2Available() === false ) {
  30. document.body.appendChild( WebGL.getWebGL2ErrorMessage() );
  31. }
  32. let renderer, scene, camera;
  33. let controls;
  34. init();
  35. animate();
  36. function init() {
  37. renderer = new THREE.WebGLRenderer();
  38. renderer.setPixelRatio( window.devicePixelRatio );
  39. renderer.setSize( window.innerWidth, window.innerHeight );
  40. document.body.appendChild( renderer.domElement );
  41. scene = new THREE.Scene();
  42. camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 0.1, 1000 );
  43. camera.position.set( 0, 0, 4 );
  44. controls = new OrbitControls( camera, renderer.domElement );
  45. controls.autoRotate = true;
  46. controls.autoRotateSpeed = - 1.0;
  47. controls.enableDamping = true;
  48. // Material
  49. const vertexShader = /* glsl */`
  50. in vec3 position;
  51. in mat4 instanceMatrix;
  52. uniform mat4 modelMatrix;
  53. uniform mat4 modelViewMatrix;
  54. uniform mat4 projectionMatrix;
  55. uniform vec3 cameraPos;
  56. out vec3 vOrigin;
  57. out vec3 vDirection;
  58. void main() {
  59. vec4 mvPosition = modelViewMatrix * instanceMatrix * vec4( position, 1.0 );
  60. vOrigin = vec3( inverse( instanceMatrix * modelMatrix ) * vec4( cameraPos, 1.0 ) ).xyz;
  61. vDirection = position - vOrigin;
  62. gl_Position = projectionMatrix * mvPosition;
  63. }
  64. `;
  65. const fragmentShader = /* glsl */`
  66. precision highp float;
  67. precision highp sampler3D;
  68. uniform mat4 modelViewMatrix;
  69. uniform mat4 projectionMatrix;
  70. in vec3 vOrigin;
  71. in vec3 vDirection;
  72. out vec4 color;
  73. uniform sampler3D map;
  74. uniform float threshold;
  75. uniform float steps;
  76. vec2 hitBox( vec3 orig, vec3 dir ) {
  77. const vec3 box_min = vec3( - 0.5 );
  78. const vec3 box_max = vec3( 0.5 );
  79. vec3 inv_dir = 1.0 / dir;
  80. vec3 tmin_tmp = ( box_min - orig ) * inv_dir;
  81. vec3 tmax_tmp = ( box_max - orig ) * inv_dir;
  82. vec3 tmin = min( tmin_tmp, tmax_tmp );
  83. vec3 tmax = max( tmin_tmp, tmax_tmp );
  84. float t0 = max( tmin.x, max( tmin.y, tmin.z ) );
  85. float t1 = min( tmax.x, min( tmax.y, tmax.z ) );
  86. return vec2( t0, t1 );
  87. }
  88. float sample1( vec3 p ) {
  89. return texture( map, p ).r;
  90. }
  91. #define epsilon .0001
  92. vec3 normal( vec3 coord ) {
  93. if ( coord.x < epsilon ) return vec3( 1.0, 0.0, 0.0 );
  94. if ( coord.y < epsilon ) return vec3( 0.0, 1.0, 0.0 );
  95. if ( coord.z < epsilon ) return vec3( 0.0, 0.0, 1.0 );
  96. if ( coord.x > 1.0 - epsilon ) return vec3( - 1.0, 0.0, 0.0 );
  97. if ( coord.y > 1.0 - epsilon ) return vec3( 0.0, - 1.0, 0.0 );
  98. if ( coord.z > 1.0 - epsilon ) return vec3( 0.0, 0.0, - 1.0 );
  99. float step = 0.01;
  100. float x = sample1( coord + vec3( - step, 0.0, 0.0 ) ) - sample1( coord + vec3( step, 0.0, 0.0 ) );
  101. float y = sample1( coord + vec3( 0.0, - step, 0.0 ) ) - sample1( coord + vec3( 0.0, step, 0.0 ) );
  102. float z = sample1( coord + vec3( 0.0, 0.0, - step ) ) - sample1( coord + vec3( 0.0, 0.0, step ) );
  103. return normalize( vec3( x, y, z ) );
  104. }
  105. void main(){
  106. vec3 rayDir = normalize( vDirection );
  107. vec2 bounds = hitBox( vOrigin, rayDir );
  108. if ( bounds.x > bounds.y ) discard;
  109. bounds.x = max( bounds.x, 0.0 );
  110. vec3 p = vOrigin + bounds.x * rayDir;
  111. vec3 inc = 1.0 / abs( rayDir );
  112. float delta = min( inc.x, min( inc.y, inc.z ) );
  113. delta /= 50.0;
  114. for ( float t = bounds.x; t < bounds.y; t += delta ) {
  115. float d = sample1( p + 0.5 );
  116. if ( d > 0.5 ) {
  117. color.rgb = p * 2.0; // normal( p + 0.5 ); // * 0.5 + ( p * 1.5 + 0.25 );
  118. color.a = 1.;
  119. break;
  120. }
  121. p += rayDir * delta;
  122. }
  123. if ( color.a == 0.0 ) discard;
  124. }
  125. `;
  126. const loader = new VOXLoader();
  127. loader.load( 'models/vox/menger.vox', function ( chunks ) {
  128. for ( let i = 0; i < chunks.length; i ++ ) {
  129. const chunk = chunks[ i ];
  130. const geometry = new THREE.BoxGeometry( 1, 1, 1 );
  131. const material = new THREE.RawShaderMaterial( {
  132. glslVersion: THREE.GLSL3,
  133. uniforms: {
  134. map: { value: new VOXData3DTexture( chunk ) },
  135. cameraPos: { value: new THREE.Vector3() }
  136. },
  137. vertexShader,
  138. fragmentShader,
  139. side: THREE.BackSide
  140. } );
  141. const mesh = new THREE.InstancedMesh( geometry, material, 50000 );
  142. mesh.onBeforeRender = function () {
  143. this.material.uniforms.cameraPos.value.copy( camera.position );
  144. };
  145. const transform = new THREE.Object3D();
  146. for ( let i = 0; i < mesh.count; i ++ ) {
  147. transform.position.random().subScalar( 0.5 ).multiplyScalar( 150 );
  148. transform.rotation.x = Math.random() * Math.PI;
  149. transform.rotation.y = Math.random() * Math.PI;
  150. transform.rotation.z = Math.random() * Math.PI;
  151. transform.updateMatrix();
  152. mesh.setMatrixAt( i, transform.matrix );
  153. }
  154. scene.add( mesh );
  155. }
  156. } );
  157. window.addEventListener( 'resize', onWindowResize );
  158. }
  159. function onWindowResize() {
  160. camera.aspect = window.innerWidth / window.innerHeight;
  161. camera.updateProjectionMatrix();
  162. renderer.setSize( window.innerWidth, window.innerHeight );
  163. }
  164. function animate() {
  165. requestAnimationFrame( animate );
  166. controls.update();
  167. renderer.render( scene, camera );
  168. }
  169. </script>
  170. </body>
  171. </html>