webgl_gpgpu_water.html 21 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - gpgpu - water</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-color: #000000;
  10. margin: 0px;
  11. overflow: hidden;
  12. font-family:Monospace;
  13. font-size:13px;
  14. text-align:center;
  15. text-align:center;
  16. }
  17. a {
  18. color:#0078ff;
  19. }
  20. #info {
  21. color: #ffffff;
  22. position: absolute;
  23. top: 10px;
  24. width: 100%;
  25. }
  26. </style>
  27. </head>
  28. <body>
  29. <div id="info">
  30. <a href="http://threejs.org" target="_blank" rel="noopener">three.js</a> - <span id="waterSize"></span> webgl gpgpu water<br/>
  31. Select <span id="options"></span> water size<br/>
  32. Move mouse to disturb water.<br>
  33. Press mouse button to orbit around. 'W' key toggles wireframe.
  34. </div>
  35. <script src="../build/three.js"></script>
  36. <script src="js/WebGL.js"></script>
  37. <script src="js/libs/stats.min.js"></script>
  38. <script src="js/libs/dat.gui.min.js"></script>
  39. <script src="js/controls/OrbitControls.js"></script>
  40. <script src="js/SimplexNoise.js"></script>
  41. <script src="js/GPUComputationRenderer.js"></script>
  42. <!-- This is the 'compute shader' for the water heightmap: -->
  43. <script id="heightmapFragmentShader" type="x-shader/x-fragment">
  44. #include <common>
  45. uniform vec2 mousePos;
  46. uniform float mouseSize;
  47. uniform float viscosityConstant;
  48. uniform float heightCompensation;
  49. void main() {
  50. vec2 cellSize = 1.0 / resolution.xy;
  51. vec2 uv = gl_FragCoord.xy * cellSize;
  52. // heightmapValue.x == height from previous frame
  53. // heightmapValue.y == height from penultimate frame
  54. // heightmapValue.z, heightmapValue.w not used
  55. vec4 heightmapValue = texture2D( heightmap, uv );
  56. // Get neighbours
  57. vec4 north = texture2D( heightmap, uv + vec2( 0.0, cellSize.y ) );
  58. vec4 south = texture2D( heightmap, uv + vec2( 0.0, - cellSize.y ) );
  59. vec4 east = texture2D( heightmap, uv + vec2( cellSize.x, 0.0 ) );
  60. vec4 west = texture2D( heightmap, uv + vec2( - cellSize.x, 0.0 ) );
  61. // https://web.archive.org/web/20080618181901/http://freespace.virgin.net/hugo.elias/graphics/x_water.htm
  62. float newHeight = ( ( north.x + south.x + east.x + west.x ) * 0.5 - heightmapValue.y ) * viscosityConstant;
  63. // Mouse influence
  64. float mousePhase = clamp( length( ( uv - vec2( 0.5 ) ) * BOUNDS - vec2( mousePos.x, - mousePos.y ) ) * PI / mouseSize, 0.0, PI );
  65. newHeight += ( cos( mousePhase ) + 1.0 ) * 0.28;
  66. heightmapValue.y = heightmapValue.x;
  67. heightmapValue.x = newHeight;
  68. gl_FragColor = heightmapValue;
  69. }
  70. </script>
  71. <!-- This is just a smoothing 'compute shader' for using manually: -->
  72. <script id="smoothFragmentShader" type="x-shader/x-fragment">
  73. uniform sampler2D texture;
  74. void main() {
  75. vec2 cellSize = 1.0 / resolution.xy;
  76. vec2 uv = gl_FragCoord.xy * cellSize;
  77. // Computes the mean of texel and 4 neighbours
  78. vec4 textureValue = texture2D( texture, uv );
  79. textureValue += texture2D( texture, uv + vec2( 0.0, cellSize.y ) );
  80. textureValue += texture2D( texture, uv + vec2( 0.0, - cellSize.y ) );
  81. textureValue += texture2D( texture, uv + vec2( cellSize.x, 0.0 ) );
  82. textureValue += texture2D( texture, uv + vec2( - cellSize.x, 0.0 ) );
  83. textureValue /= 5.0;
  84. gl_FragColor = textureValue;
  85. }
  86. </script>
  87. <!-- This is a 'compute shader' to read the current level and normal of water at a point -->
  88. <!-- It is used with a variable of size 1x1 -->
  89. <script id="readWaterLevelFragmentShader" type="x-shader/x-fragment">
  90. uniform vec2 point1;
  91. uniform sampler2D texture;
  92. // Integer to float conversion from https://stackoverflow.com/questions/17981163/webgl-read-pixels-from-floating-point-render-target
  93. float shift_right( float v, float amt ) {
  94. v = floor( v ) + 0.5;
  95. return floor( v / exp2( amt ) );
  96. }
  97. float shift_left( float v, float amt ) {
  98. return floor( v * exp2( amt ) + 0.5 );
  99. }
  100. float mask_last( float v, float bits ) {
  101. return mod( v, shift_left( 1.0, bits ) );
  102. }
  103. float extract_bits( float num, float from, float to ) {
  104. from = floor( from + 0.5 ); to = floor( to + 0.5 );
  105. return mask_last( shift_right( num, from ), to - from );
  106. }
  107. vec4 encode_float( float val ) {
  108. if ( val == 0.0 ) return vec4( 0, 0, 0, 0 );
  109. float sign = val > 0.0 ? 0.0 : 1.0;
  110. val = abs( val );
  111. float exponent = floor( log2( val ) );
  112. float biased_exponent = exponent + 127.0;
  113. float fraction = ( ( val / exp2( exponent ) ) - 1.0 ) * 8388608.0;
  114. float t = biased_exponent / 2.0;
  115. float last_bit_of_biased_exponent = fract( t ) * 2.0;
  116. float remaining_bits_of_biased_exponent = floor( t );
  117. float byte4 = extract_bits( fraction, 0.0, 8.0 ) / 255.0;
  118. float byte3 = extract_bits( fraction, 8.0, 16.0 ) / 255.0;
  119. float byte2 = ( last_bit_of_biased_exponent * 128.0 + extract_bits( fraction, 16.0, 23.0 ) ) / 255.0;
  120. float byte1 = ( sign * 128.0 + remaining_bits_of_biased_exponent ) / 255.0;
  121. return vec4( byte4, byte3, byte2, byte1 );
  122. }
  123. void main() {
  124. vec2 cellSize = 1.0 / resolution.xy;
  125. float waterLevel = texture2D( texture, point1 ).x;
  126. vec2 normal = vec2(
  127. ( texture2D( texture, point1 + vec2( - cellSize.x, 0 ) ).x - texture2D( texture, point1 + vec2( cellSize.x, 0 ) ).x ) * WIDTH / BOUNDS,
  128. ( texture2D( texture, point1 + vec2( 0, - cellSize.y ) ).x - texture2D( texture, point1 + vec2( 0, cellSize.y ) ).x ) * WIDTH / BOUNDS );
  129. if ( gl_FragCoord.x < 1.5 ) {
  130. gl_FragColor = encode_float( waterLevel );
  131. } else if ( gl_FragCoord.x < 2.5 ) {
  132. gl_FragColor = encode_float( normal.x );
  133. } else if ( gl_FragCoord.x < 3.5 ) {
  134. gl_FragColor = encode_float( normal.y );
  135. } else {
  136. gl_FragColor = encode_float( 0.0 );
  137. }
  138. }
  139. </script>
  140. <!-- This is the water visualization shader, copied from the MeshPhongMaterial and modified: -->
  141. <script id="waterVertexShader" type="x-shader/x-vertex">
  142. uniform sampler2D heightmap;
  143. #define PHONG
  144. varying vec3 vViewPosition;
  145. #ifndef FLAT_SHADED
  146. varying vec3 vNormal;
  147. #endif
  148. #include <common>
  149. #include <uv_pars_vertex>
  150. #include <uv2_pars_vertex>
  151. #include <displacementmap_pars_vertex>
  152. #include <envmap_pars_vertex>
  153. #include <color_pars_vertex>
  154. #include <morphtarget_pars_vertex>
  155. #include <skinning_pars_vertex>
  156. #include <shadowmap_pars_vertex>
  157. #include <logdepthbuf_pars_vertex>
  158. #include <clipping_planes_pars_vertex>
  159. void main() {
  160. vec2 cellSize = vec2( 1.0 / WIDTH, 1.0 / WIDTH );
  161. #include <uv_vertex>
  162. #include <uv2_vertex>
  163. #include <color_vertex>
  164. // # include <beginnormal_vertex>
  165. // Compute normal from heightmap
  166. vec3 objectNormal = vec3(
  167. ( texture2D( heightmap, uv + vec2( - cellSize.x, 0 ) ).x - texture2D( heightmap, uv + vec2( cellSize.x, 0 ) ).x ) * WIDTH / BOUNDS,
  168. ( texture2D( heightmap, uv + vec2( 0, - cellSize.y ) ).x - texture2D( heightmap, uv + vec2( 0, cellSize.y ) ).x ) * WIDTH / BOUNDS,
  169. 1.0 );
  170. //<beginnormal_vertex>
  171. #include <morphnormal_vertex>
  172. #include <skinbase_vertex>
  173. #include <skinnormal_vertex>
  174. #include <defaultnormal_vertex>
  175. #ifndef FLAT_SHADED // Normal computed with derivatives when FLAT_SHADED
  176. vNormal = normalize( transformedNormal );
  177. #endif
  178. //# include <begin_vertex>
  179. float heightValue = texture2D( heightmap, uv ).x;
  180. vec3 transformed = vec3( position.x, position.y, heightValue );
  181. //<begin_vertex>
  182. #include <morphtarget_vertex>
  183. #include <skinning_vertex>
  184. #include <displacementmap_vertex>
  185. #include <project_vertex>
  186. #include <logdepthbuf_vertex>
  187. #include <clipping_planes_vertex>
  188. vViewPosition = - mvPosition.xyz;
  189. #include <worldpos_vertex>
  190. #include <envmap_vertex>
  191. #include <shadowmap_vertex>
  192. }
  193. </script>
  194. <script>
  195. if ( WEBGL.isWebGLAvailable() === false ) {
  196. document.body.appendChild( WEBGL.getWebGLErrorMessage() );
  197. }
  198. var hash = document.location.hash.substr( 1 );
  199. if ( hash ) hash = parseInt( hash, 0 );
  200. // Texture width for simulation
  201. var WIDTH = hash || 128;
  202. // Water size in system units
  203. var BOUNDS = 512;
  204. var BOUNDS_HALF = BOUNDS * 0.5;
  205. var container, stats;
  206. var camera, scene, renderer;
  207. var mouseMoved = false;
  208. var mouseCoords = new THREE.Vector2();
  209. var raycaster = new THREE.Raycaster();
  210. var waterMesh;
  211. var meshRay;
  212. var gpuCompute;
  213. var heightmapVariable;
  214. var waterUniforms;
  215. var smoothShader;
  216. var readWaterLevelShader;
  217. var readWaterLevelRenderTarget;
  218. var readWaterLevelImage;
  219. var waterNormal = new THREE.Vector3();
  220. var NUM_SPHERES = 5;
  221. var spheres = [];
  222. var spheresEnabled = true;
  223. var simplex = new SimplexNoise();
  224. document.getElementById( 'waterSize' ).innerText = WIDTH + ' x ' + WIDTH;
  225. function change( n ) {
  226. location.hash = n;
  227. location.reload();
  228. return false;
  229. }
  230. var options = '';
  231. for ( var i = 4; i < 10; i ++ ) {
  232. var j = Math.pow( 2, i );
  233. options += '<a href="#" onclick="return change(' + j + ')">' + j + 'x' + j + '</a> ';
  234. }
  235. document.getElementById( 'options' ).innerHTML = options;
  236. init();
  237. animate();
  238. function init() {
  239. container = document.createElement( 'div' );
  240. document.body.appendChild( container );
  241. camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 1, 3000 );
  242. camera.position.set( 0, 200, 350 );
  243. scene = new THREE.Scene();
  244. var sun = new THREE.DirectionalLight( 0xFFFFFF, 1.0 );
  245. sun.position.set( 300, 400, 175 );
  246. scene.add( sun );
  247. var sun2 = new THREE.DirectionalLight( 0x40A040, 0.6 );
  248. sun2.position.set( - 100, 350, - 200 );
  249. scene.add( sun2 );
  250. renderer = new THREE.WebGLRenderer();
  251. renderer.setPixelRatio( window.devicePixelRatio );
  252. renderer.setSize( window.innerWidth, window.innerHeight );
  253. container.appendChild( renderer.domElement );
  254. var controls = new THREE.OrbitControls( camera, renderer.domElement );
  255. stats = new Stats();
  256. container.appendChild( stats.dom );
  257. document.addEventListener( 'mousemove', onDocumentMouseMove, false );
  258. document.addEventListener( 'touchstart', onDocumentTouchStart, false );
  259. document.addEventListener( 'touchmove', onDocumentTouchMove, false );
  260. document.addEventListener( 'keydown', function ( event ) {
  261. // W Pressed: Toggle wireframe
  262. if ( event.keyCode === 87 ) {
  263. waterMesh.material.wireframe = ! waterMesh.material.wireframe;
  264. waterMesh.material.needsUpdate = true;
  265. }
  266. }, false );
  267. window.addEventListener( 'resize', onWindowResize, false );
  268. var gui = new dat.GUI();
  269. var effectController = {
  270. mouseSize: 20.0,
  271. viscosity: 0.98,
  272. spheresEnabled: spheresEnabled
  273. };
  274. var valuesChanger = function () {
  275. heightmapVariable.material.uniforms[ "mouseSize" ].value = effectController.mouseSize;
  276. heightmapVariable.material.uniforms[ "viscosityConstant" ].value = effectController.viscosity;
  277. spheresEnabled = effectController.spheresEnabled;
  278. for ( var i = 0; i < NUM_SPHERES; i ++ ) {
  279. if ( spheres[ i ] ) {
  280. spheres[ i ].visible = spheresEnabled;
  281. }
  282. }
  283. };
  284. gui.add( effectController, "mouseSize", 1.0, 100.0, 1.0 ).onChange( valuesChanger );
  285. gui.add( effectController, "viscosity", 0.9, 0.999, 0.001 ).onChange( valuesChanger );
  286. gui.add( effectController, "spheresEnabled", 0, 1, 1 ).onChange( valuesChanger );
  287. var buttonSmooth = {
  288. smoothWater: function () {
  289. smoothWater();
  290. }
  291. };
  292. gui.add( buttonSmooth, 'smoothWater' );
  293. initWater();
  294. createSpheres();
  295. valuesChanger();
  296. }
  297. function initWater() {
  298. var materialColor = 0x0040C0;
  299. var geometry = new THREE.PlaneBufferGeometry( BOUNDS, BOUNDS, WIDTH - 1, WIDTH - 1 );
  300. // material: make a ShaderMaterial clone of MeshPhongMaterial, with customized vertex shader
  301. var material = new THREE.ShaderMaterial( {
  302. uniforms: THREE.UniformsUtils.merge( [
  303. THREE.ShaderLib[ 'phong' ].uniforms,
  304. {
  305. "heightmap": { value: null }
  306. }
  307. ] ),
  308. vertexShader: document.getElementById( 'waterVertexShader' ).textContent,
  309. fragmentShader: THREE.ShaderChunk[ 'meshphong_frag' ]
  310. } );
  311. material.lights = true;
  312. // Material attributes from MeshPhongMaterial
  313. material.color = new THREE.Color( materialColor );
  314. material.specular = new THREE.Color( 0x111111 );
  315. material.shininess = 50;
  316. // Sets the uniforms with the material values
  317. material.uniforms[ "diffuse" ].value = material.color;
  318. material.uniforms[ "specular" ].value = material.specular;
  319. material.uniforms[ "shininess" ].value = Math.max( material.shininess, 1e-4 );
  320. material.uniforms[ "opacity" ].value = material.opacity;
  321. // Defines
  322. material.defines.WIDTH = WIDTH.toFixed( 1 );
  323. material.defines.BOUNDS = BOUNDS.toFixed( 1 );
  324. waterUniforms = material.uniforms;
  325. waterMesh = new THREE.Mesh( geometry, material );
  326. waterMesh.rotation.x = - Math.PI / 2;
  327. waterMesh.matrixAutoUpdate = false;
  328. waterMesh.updateMatrix();
  329. scene.add( waterMesh );
  330. // Mesh just for mouse raycasting
  331. var geometryRay = new THREE.PlaneBufferGeometry( BOUNDS, BOUNDS, 1, 1 );
  332. meshRay = new THREE.Mesh( geometryRay, new THREE.MeshBasicMaterial( { color: 0xFFFFFF, visible: false } ) );
  333. meshRay.rotation.x = - Math.PI / 2;
  334. meshRay.matrixAutoUpdate = false;
  335. meshRay.updateMatrix();
  336. scene.add( meshRay );
  337. // Creates the gpu computation class and sets it up
  338. gpuCompute = new GPUComputationRenderer( WIDTH, WIDTH, renderer );
  339. var heightmap0 = gpuCompute.createTexture();
  340. fillTexture( heightmap0 );
  341. heightmapVariable = gpuCompute.addVariable( "heightmap", document.getElementById( 'heightmapFragmentShader' ).textContent, heightmap0 );
  342. gpuCompute.setVariableDependencies( heightmapVariable, [ heightmapVariable ] );
  343. heightmapVariable.material.uniforms[ "mousePos" ] = { value: new THREE.Vector2( 10000, 10000 ) };
  344. heightmapVariable.material.uniforms[ "mouseSize" ] = { value: 20.0 };
  345. heightmapVariable.material.uniforms[ "viscosityConstant" ] = { value: 0.98 };
  346. heightmapVariable.material.uniforms[ "heightCompensation" ] = { value: 0 };
  347. heightmapVariable.material.defines.BOUNDS = BOUNDS.toFixed( 1 );
  348. var error = gpuCompute.init();
  349. if ( error !== null ) {
  350. console.error( error );
  351. }
  352. // Create compute shader to smooth the water surface and velocity
  353. smoothShader = gpuCompute.createShaderMaterial( document.getElementById( 'smoothFragmentShader' ).textContent, { texture: { value: null } } );
  354. // Create compute shader to read water level
  355. readWaterLevelShader = gpuCompute.createShaderMaterial( document.getElementById( 'readWaterLevelFragmentShader' ).textContent, {
  356. point1: { value: new THREE.Vector2() },
  357. texture: { value: null }
  358. } );
  359. readWaterLevelShader.defines.WIDTH = WIDTH.toFixed( 1 );
  360. readWaterLevelShader.defines.BOUNDS = BOUNDS.toFixed( 1 );
  361. // Create a 4x1 pixel image and a render target (Uint8, 4 channels, 1 byte per channel) to read water height and orientation
  362. readWaterLevelImage = new Uint8Array( 4 * 1 * 4 );
  363. readWaterLevelRenderTarget = new THREE.WebGLRenderTarget( 4, 1, {
  364. wrapS: THREE.ClampToEdgeWrapping,
  365. wrapT: THREE.ClampToEdgeWrapping,
  366. minFilter: THREE.NearestFilter,
  367. magFilter: THREE.NearestFilter,
  368. format: THREE.RGBAFormat,
  369. type: THREE.UnsignedByteType,
  370. stencilBuffer: false,
  371. depthBuffer: false
  372. } );
  373. }
  374. function fillTexture( texture ) {
  375. var waterMaxHeight = 10;
  376. function noise( x, y ) {
  377. var multR = waterMaxHeight;
  378. var mult = 0.025;
  379. var r = 0;
  380. for ( var i = 0; i < 15; i ++ ) {
  381. r += multR * simplex.noise( x * mult, y * mult );
  382. multR *= 0.53 + 0.025 * i;
  383. mult *= 1.25;
  384. }
  385. return r;
  386. }
  387. var pixels = texture.image.data;
  388. var p = 0;
  389. for ( var j = 0; j < WIDTH; j ++ ) {
  390. for ( var i = 0; i < WIDTH; i ++ ) {
  391. var x = i * 128 / WIDTH;
  392. var y = j * 128 / WIDTH;
  393. pixels[ p + 0 ] = noise( x, y, 123.4 );
  394. pixels[ p + 1 ] = pixels[ p + 0 ];
  395. pixels[ p + 2 ] = 0;
  396. pixels[ p + 3 ] = 1;
  397. p += 4;
  398. }
  399. }
  400. }
  401. function smoothWater() {
  402. var currentRenderTarget = gpuCompute.getCurrentRenderTarget( heightmapVariable );
  403. var alternateRenderTarget = gpuCompute.getAlternateRenderTarget( heightmapVariable );
  404. for ( var i = 0; i < 10; i ++ ) {
  405. smoothShader.uniforms[ "texture" ].value = currentRenderTarget.texture;
  406. gpuCompute.doRenderTarget( smoothShader, alternateRenderTarget );
  407. smoothShader.uniforms[ "texture" ].value = alternateRenderTarget.texture;
  408. gpuCompute.doRenderTarget( smoothShader, currentRenderTarget );
  409. }
  410. }
  411. function createSpheres() {
  412. var sphereTemplate = new THREE.Mesh( new THREE.SphereBufferGeometry( 4, 24, 12 ), new THREE.MeshPhongMaterial( { color: 0xFFFF00 } ) );
  413. for ( var i = 0; i < NUM_SPHERES; i ++ ) {
  414. var sphere = sphereTemplate;
  415. if ( i < NUM_SPHERES - 1 ) {
  416. sphere = sphereTemplate.clone();
  417. }
  418. sphere.position.x = ( Math.random() - 0.5 ) * BOUNDS * 0.7;
  419. sphere.position.z = ( Math.random() - 0.5 ) * BOUNDS * 0.7;
  420. sphere.userData.velocity = new THREE.Vector3();
  421. scene.add( sphere );
  422. spheres[ i ] = sphere;
  423. }
  424. }
  425. function sphereDynamics() {
  426. var currentRenderTarget = gpuCompute.getCurrentRenderTarget( heightmapVariable );
  427. readWaterLevelShader.uniforms[ "texture" ].value = currentRenderTarget.texture;
  428. var gl = renderer.context;
  429. for ( var i = 0; i < NUM_SPHERES; i ++ ) {
  430. var sphere = spheres[ i ];
  431. if ( sphere ) {
  432. // Read water level and orientation
  433. var u = 0.5 * sphere.position.x / BOUNDS_HALF + 0.5;
  434. var v = 1 - ( 0.5 * sphere.position.z / BOUNDS_HALF + 0.5 );
  435. readWaterLevelShader.uniforms[ "point1" ].value.set( u, v );
  436. gpuCompute.doRenderTarget( readWaterLevelShader, readWaterLevelRenderTarget );
  437. gl.readPixels( 0, 0, 4, 1, gl.RGBA, gl.UNSIGNED_BYTE, readWaterLevelImage );
  438. var pixels = new Float32Array( readWaterLevelImage.buffer );
  439. // Get orientation
  440. waterNormal.set( pixels[ 1 ], 0, - pixels[ 2 ] );
  441. var pos = sphere.position;
  442. // Set height
  443. pos.y = pixels[ 0 ];
  444. // Move sphere
  445. waterNormal.multiplyScalar( 0.1 );
  446. sphere.userData.velocity.add( waterNormal );
  447. sphere.userData.velocity.multiplyScalar( 0.998 );
  448. pos.add( sphere.userData.velocity );
  449. if ( pos.x < - BOUNDS_HALF ) {
  450. pos.x = - BOUNDS_HALF + 0.001;
  451. sphere.userData.velocity.x *= - 0.3;
  452. } else if ( pos.x > BOUNDS_HALF ) {
  453. pos.x = BOUNDS_HALF - 0.001;
  454. sphere.userData.velocity.x *= - 0.3;
  455. }
  456. if ( pos.z < - BOUNDS_HALF ) {
  457. pos.z = - BOUNDS_HALF + 0.001;
  458. sphere.userData.velocity.z *= - 0.3;
  459. } else if ( pos.z > BOUNDS_HALF ) {
  460. pos.z = BOUNDS_HALF - 0.001;
  461. sphere.userData.velocity.z *= - 0.3;
  462. }
  463. }
  464. }
  465. }
  466. function onWindowResize() {
  467. camera.aspect = window.innerWidth / window.innerHeight;
  468. camera.updateProjectionMatrix();
  469. renderer.setSize( window.innerWidth, window.innerHeight );
  470. }
  471. function setMouseCoords( x, y ) {
  472. mouseCoords.set( ( x / renderer.domElement.clientWidth ) * 2 - 1, - ( y / renderer.domElement.clientHeight ) * 2 + 1 );
  473. mouseMoved = true;
  474. }
  475. function onDocumentMouseMove( event ) {
  476. setMouseCoords( event.clientX, event.clientY );
  477. }
  478. function onDocumentTouchStart( event ) {
  479. if ( event.touches.length === 1 ) {
  480. event.preventDefault();
  481. setMouseCoords( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  482. }
  483. }
  484. function onDocumentTouchMove( event ) {
  485. if ( event.touches.length === 1 ) {
  486. event.preventDefault();
  487. setMouseCoords( event.touches[ 0 ].pageX, event.touches[ 0 ].pageY );
  488. }
  489. }
  490. function animate() {
  491. requestAnimationFrame( animate );
  492. render();
  493. stats.update();
  494. }
  495. function render() {
  496. // Set uniforms: mouse interaction
  497. var uniforms = heightmapVariable.material.uniforms;
  498. if ( mouseMoved ) {
  499. raycaster.setFromCamera( mouseCoords, camera );
  500. var intersects = raycaster.intersectObject( meshRay );
  501. if ( intersects.length > 0 ) {
  502. var point = intersects[ 0 ].point;
  503. uniforms[ "mousePos" ].value.set( point.x, point.z );
  504. } else {
  505. uniforms[ "mousePos" ].value.set( 10000, 10000 );
  506. }
  507. mouseMoved = false;
  508. } else {
  509. uniforms[ "mousePos" ].value.set( 10000, 10000 );
  510. }
  511. // Do the gpu computation
  512. gpuCompute.compute();
  513. if ( spheresEnabled ) {
  514. sphereDynamics();
  515. }
  516. // Get compute output in custom uniform
  517. waterUniforms[ "heightmap" ].value = gpuCompute.getCurrentRenderTarget( heightmapVariable ).texture;
  518. // Render
  519. renderer.render( scene, camera );
  520. }
  521. </script>
  522. </body>
  523. </html>