webgl_raymarching_reflect.html 7.5 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="utf-8">
  5. <meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
  6. <title>three.js webgl - raymarching - reflect</title>
  7. <style type="text/css">
  8. body {
  9. background-color: black;
  10. margin: 0;
  11. padding: 0;
  12. }
  13. a { color: skyblue }
  14. canvas {
  15. display: block;
  16. position: absolute;
  17. top: 0;
  18. left: 0;
  19. right: 0;
  20. bottom: 0;
  21. margin: auto;
  22. }
  23. #info {
  24. color: white;
  25. font-size: 13px;
  26. position: absolute;
  27. bottom: 10px;
  28. width: 100%;
  29. text-align: center;
  30. z-index: 100;
  31. }
  32. </style>
  33. </head>
  34. <body>
  35. <div id="info">
  36. <a href="http://threejs.org" target="_blank">three.js</a> - webgl raymarching example -
  37. reflect by <a href="https://github.com/gam0022" target="_blank">gam0022</a> (<a href="http://qiita.com/gam0022/items/03699a07e4a4b5f2d41f" target="_blank">article in Japanese</a>)
  38. </div>
  39. <script id="fragment_shader" type="x-shader/x-fragment">
  40. precision highp float;
  41. uniform float time;
  42. uniform vec2 resolution;
  43. uniform vec2 mouse;
  44. const float EPS = 0.01;
  45. const float OFFSET = EPS * 100.0;
  46. const vec3 lightDir = vec3( -0.48666426339228763, 0.8111071056538127, -0.3244428422615251 );
  47. // distance functions
  48. vec3 onRep( vec3 p, float interval ) {
  49. vec2 q = mod( p.xz, interval ) - interval * 0.5;
  50. return vec3( q.x, p.y, q.y );
  51. }
  52. float sphereDist( vec3 p, float r ) {
  53. return length( onRep( p, 3.0 ) ) - r;
  54. }
  55. float floorDist( vec3 p ){
  56. return dot(p, vec3( 0.0, 1.0, 0.0 ) ) + 1.0;
  57. }
  58. vec4 minVec4( vec4 a, vec4 b ) {
  59. return ( a.a < b.a ) ? a : b;
  60. }
  61. float checkeredPattern( vec3 p ) {
  62. float u = 1.0 - floor( mod( p.x, 2.0 ) );
  63. float v = 1.0 - floor( mod( p.z, 2.0 ) );
  64. if ( ( u == 1.0 && v < 1.0 ) || ( u < 1.0 && v == 1.0 ) ) {
  65. return 0.2;
  66. } else {
  67. return 1.0;
  68. }
  69. }
  70. vec3 hsv2rgb( vec3 c ) {
  71. vec4 K = vec4( 1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0 );
  72. vec3 p = abs( fract( c.xxx + K.xyz ) * 6.0 - K.www );
  73. return c.z * mix( K.xxx, clamp( p - K.xxx, 0.0, 1.0 ), c.y );
  74. }
  75. float sceneDist( vec3 p ) {
  76. return min(
  77. sphereDist( p, 1.0 ),
  78. floorDist( p )
  79. );
  80. }
  81. vec4 sceneColor( vec3 p ) {
  82. return minVec4(
  83. // 3 * 6 / 2 = 9
  84. vec4( hsv2rgb(vec3( ( p.z + p.x ) / 9.0, 1.0, 1.0 ) ), sphereDist( p, 1.0 ) ),
  85. vec4( vec3( 0.5 ) * checkeredPattern( p ), floorDist( p ) )
  86. );
  87. }
  88. vec3 getNormal( vec3 p ) {
  89. return normalize(vec3(
  90. sceneDist(p + vec3( EPS, 0.0, 0.0 ) ) - sceneDist(p + vec3( -EPS, 0.0, 0.0 ) ),
  91. sceneDist(p + vec3( 0.0, EPS, 0.0 ) ) - sceneDist(p + vec3( 0.0, -EPS, 0.0 ) ),
  92. sceneDist(p + vec3( 0.0, 0.0, EPS ) ) - sceneDist(p + vec3( 0.0, 0.0, -EPS ) )
  93. ));
  94. }
  95. float getShadow( vec3 ro, vec3 rd ) {
  96. float h = 0.0;
  97. float c = 0.0;
  98. float r = 1.0;
  99. float shadowCoef = 0.5;
  100. for ( float t = 0.0; t < 50.0; t++ ) {
  101. h = sceneDist( ro + rd * c );
  102. if ( h < EPS ) return shadowCoef;
  103. r = min( r, h * 16.0 / c );
  104. c += h;
  105. }
  106. return 1.0 - shadowCoef + r * shadowCoef;
  107. }
  108. vec3 getRayColor( vec3 origin, vec3 ray, out vec3 p, out vec3 normal, out bool hit ) {
  109. // marching loop
  110. float dist;
  111. float depth = 0.0;
  112. p = origin;
  113. for ( int i = 0; i < 64; i++ ){
  114. dist = sceneDist( p );
  115. depth += dist;
  116. p = origin + depth * ray;
  117. if ( abs(dist) < EPS ) break;
  118. }
  119. // hit check and calc color
  120. vec3 color;
  121. if ( abs(dist) < EPS ) {
  122. normal = getNormal(p);
  123. float diffuse = clamp( dot( lightDir, normal ), 0.1, 1.0 );
  124. float specular = pow( clamp( dot( reflect( lightDir, normal ), ray ), 0.0, 1.0 ), 10.0 );
  125. float shadow = getShadow( p + normal * OFFSET, lightDir );
  126. color = ( sceneColor( p ).rgb * diffuse + vec3( 0.8 ) * specular ) * max( 0.5, shadow );
  127. hit = true;
  128. } else {
  129. color = vec3( 0.0 );
  130. }
  131. return color - pow( clamp( 0.05 * depth, 0.0, 0.6 ), 2.0 );
  132. }
  133. void main(void) {
  134. // fragment position
  135. vec2 p = ( gl_FragCoord.xy * 2.0 - resolution ) / min( resolution.x, resolution.y );
  136. // camera and ray
  137. vec3 cPos = vec3( mouse.x - 0.5, mouse.y * 4.0 - 0.2, time );
  138. vec3 cDir = normalize( vec3( 0.0, -0.3, 1.0 ) );
  139. vec3 cUp = cross( cDir, vec3( 1.0, 0.0 ,0.0 ) );
  140. vec3 cSide = cross( cDir, cUp );
  141. float targetDepth = 1.3;
  142. vec3 ray = normalize( cSide * p.x + cUp * p.y + cDir * targetDepth );
  143. vec3 color = vec3( 0.0 );
  144. vec3 q, normal;
  145. bool hit;
  146. float alpha = 1.0;
  147. for ( int i = 0; i < 3; i++ ) {
  148. color += alpha * getRayColor( cPos, ray, q, normal, hit );
  149. alpha *= 0.3;
  150. ray = normalize( reflect( ray, normal ) );
  151. cPos = q + normal * OFFSET;
  152. if ( !hit ) break;
  153. }
  154. gl_FragColor = vec4(color, 1.0);
  155. }
  156. </script>
  157. <script id="vertex_shader" type="x-shader/x-vertex">
  158. attribute vec3 position;
  159. void main(void) {
  160. gl_Position = vec4(position, 1.0);
  161. }
  162. </script>
  163. <script src="../build/three.min.js"></script>
  164. <script src="js/libs/stats.min.js"></script>
  165. <script src="js/libs/dat.gui.min.js"></script>
  166. <script>
  167. var scene, camera, renderer;
  168. var geometry, material, mesh;
  169. var mouse = new THREE.Vector2( 0.5, 0.5 );
  170. var canvas;
  171. var stats;
  172. var config = {
  173. saveImage: function() {
  174. renderer.render( scene, camera );
  175. window.open( canvas.toDataURL() );
  176. },
  177. recursion: 3,
  178. resolution: '512',
  179. };
  180. init();
  181. render();
  182. function init() {
  183. scene = new THREE.Scene();
  184. camera = new THREE.Camera();
  185. geometry = new THREE.PlaneBufferGeometry( 2.0, 2.0 );
  186. material = new THREE.RawShaderMaterial( {
  187. uniforms: {
  188. time: { type: 'f', value: 0.0 },
  189. resolution: { type: 'v2', value: new THREE.Vector2( 512, 512 ) },
  190. mouse: { type: 'v2', value: mouse },
  191. },
  192. vertexShader: document.getElementById( 'vertex_shader' ).textContent,
  193. fragmentShader: document.getElementById( 'fragment_shader' ).textContent
  194. } );
  195. mesh = new THREE.Mesh( geometry, material );
  196. scene.add( mesh );
  197. renderer = new THREE.WebGLRenderer();
  198. renderer.setPixelRatio( window.devicePixelRatio );
  199. renderer.setSize( 512, 512 );
  200. canvas = renderer.domElement;
  201. canvas.addEventListener( 'mousemove', onMouseMove );
  202. window.addEventListener( 'resize', onWindowResize );
  203. document.body.appendChild( canvas );
  204. var gui = new dat.GUI();
  205. gui.add( config, 'saveImage' ).name( 'Save Image' );
  206. gui.add( config, 'resolution', [ '256', '512', '800', 'full' ] ).name( 'Resolution' ).onChange( function( value ) {
  207. if ( value !== 'full' ) {
  208. canvas.width = value;
  209. canvas.height = value;
  210. }
  211. onWindowResize();
  212. } );
  213. stats = new Stats();
  214. document.body.appendChild( stats.domElement );
  215. }
  216. function render( timestamp ) {
  217. stats.begin();
  218. material.uniforms.time.value = timestamp * 0.001;
  219. material.uniforms.resolution.value = new THREE.Vector2( canvas.width, canvas.height );
  220. material.uniforms.mouse.value = mouse;
  221. renderer.render( scene, camera );
  222. stats.end();
  223. requestAnimationFrame( render );
  224. }
  225. function onMouseMove( e ) {
  226. mouse.x = e.offsetX / canvas.width;
  227. mouse.y = e.offsetY / canvas.height;
  228. }
  229. function onWindowResize( e ) {
  230. if ( config.resolution === 'full' ) {
  231. canvas.width = window.innerWidth;
  232. canvas.height = window.innerHeight;
  233. }
  234. renderer.setSize( canvas.width, canvas.height );
  235. }
  236. </script>
  237. </body>
  238. </html>