webgl_gpgpu_birds_gltf.html 20 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <title>three.js webgl - gpgpu - flocking</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. <style>
  9. body {
  10. background-color: #fff;
  11. color: #444;
  12. }
  13. a {
  14. color:#08f;
  15. }
  16. </style>
  17. </head>
  18. <body>
  19. <div id="info">
  20. <a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - webgl gpgpu birds + GLTF mesh<br/>
  21. Flamingo by <a href="https://mirada.com/" target="_blank" rel="noopener">mirada</a> from <a href="http://www.ro.me/" target="_blank" rel="noopener">rome</a><br/>
  22. Move mouse to disturb birds.
  23. </div>
  24. <!-- shader for bird's position -->
  25. <script id="fragmentShaderPosition" type="x-shader/x-fragment">
  26. uniform float time;
  27. uniform float delta;
  28. void main() {
  29. vec2 uv = gl_FragCoord.xy / resolution.xy;
  30. vec4 tmpPos = texture2D( texturePosition, uv );
  31. vec3 position = tmpPos.xyz;
  32. vec3 velocity = texture2D( textureVelocity, uv ).xyz;
  33. float phase = tmpPos.w;
  34. phase = mod( ( phase + delta +
  35. length( velocity.xz ) * delta * 3. +
  36. max( velocity.y, 0.0 ) * delta * 6. ), 62.83 );
  37. gl_FragColor = vec4( position + velocity * delta * 15. , phase );
  38. }
  39. </script>
  40. <!-- shader for bird's velocity -->
  41. <script id="fragmentShaderVelocity" type="x-shader/x-fragment">
  42. uniform float time;
  43. uniform float testing;
  44. uniform float delta; // about 0.016
  45. uniform float separationDistance; // 20
  46. uniform float alignmentDistance; // 40
  47. uniform float cohesionDistance; //
  48. uniform float freedomFactor;
  49. uniform vec3 predator;
  50. const float width = resolution.x;
  51. const float height = resolution.y;
  52. const float PI = 3.141592653589793;
  53. const float PI_2 = PI * 2.0;
  54. // const float VISION = PI * 0.55;
  55. float zoneRadius = 40.0;
  56. float zoneRadiusSquared = 1600.0;
  57. float separationThresh = 0.45;
  58. float alignmentThresh = 0.65;
  59. const float UPPER_BOUNDS = BOUNDS;
  60. const float LOWER_BOUNDS = -UPPER_BOUNDS;
  61. const float SPEED_LIMIT = 9.0;
  62. float rand( vec2 co ){
  63. return fract( sin( dot( co.xy, vec2(12.9898,78.233) ) ) * 43758.5453 );
  64. }
  65. void main() {
  66. zoneRadius = separationDistance + alignmentDistance + cohesionDistance;
  67. separationThresh = separationDistance / zoneRadius;
  68. alignmentThresh = ( separationDistance + alignmentDistance ) / zoneRadius;
  69. zoneRadiusSquared = zoneRadius * zoneRadius;
  70. vec2 uv = gl_FragCoord.xy / resolution.xy;
  71. vec3 birdPosition, birdVelocity;
  72. vec3 selfPosition = texture2D( texturePosition, uv ).xyz;
  73. vec3 selfVelocity = texture2D( textureVelocity, uv ).xyz;
  74. float dist;
  75. vec3 dir; // direction
  76. float distSquared;
  77. float separationSquared = separationDistance * separationDistance;
  78. float cohesionSquared = cohesionDistance * cohesionDistance;
  79. float f;
  80. float percent;
  81. vec3 velocity = selfVelocity;
  82. float limit = SPEED_LIMIT;
  83. dir = predator * UPPER_BOUNDS - selfPosition;
  84. dir.z = 0.;
  85. // dir.z *= 0.6;
  86. dist = length( dir );
  87. distSquared = dist * dist;
  88. float preyRadius = 150.0;
  89. float preyRadiusSq = preyRadius * preyRadius;
  90. // move birds away from predator
  91. if ( dist < preyRadius ) {
  92. f = ( distSquared / preyRadiusSq - 1.0 ) * delta * 100.;
  93. velocity += normalize( dir ) * f;
  94. limit += 5.0;
  95. }
  96. // if (testing == 0.0) {}
  97. // if ( rand( uv + time ) < freedomFactor ) {}
  98. // Attract flocks to the center
  99. vec3 central = vec3( 0., 0., 0. );
  100. dir = selfPosition - central;
  101. dist = length( dir );
  102. dir.y *= 2.5;
  103. velocity -= normalize( dir ) * delta * 5.;
  104. for ( float y = 0.0; y < height; y++ ) {
  105. for ( float x = 0.0; x < width; x++ ) {
  106. vec2 ref = vec2( x + 0.5, y + 0.5 ) / resolution.xy;
  107. birdPosition = texture2D( texturePosition, ref ).xyz;
  108. dir = birdPosition - selfPosition;
  109. dist = length( dir );
  110. if ( dist < 0.0001 ) continue;
  111. distSquared = dist * dist;
  112. if ( distSquared > zoneRadiusSquared ) continue;
  113. percent = distSquared / zoneRadiusSquared;
  114. if ( percent < separationThresh ) { // low
  115. // Separation - Move apart for comfort
  116. f = ( separationThresh / percent - 1.0 ) * delta;
  117. velocity -= normalize( dir ) * f;
  118. } else if ( percent < alignmentThresh ) { // high
  119. // Alignment - fly the same direction
  120. float threshDelta = alignmentThresh - separationThresh;
  121. float adjustedPercent = ( percent - separationThresh ) / threshDelta;
  122. birdVelocity = texture2D( textureVelocity, ref ).xyz;
  123. f = ( 0.5 - cos( adjustedPercent * PI_2 ) * 0.5 + 0.5 ) * delta;
  124. velocity += normalize( birdVelocity ) * f;
  125. } else {
  126. // Attraction / Cohesion - move closer
  127. float threshDelta = 1.0 - alignmentThresh;
  128. float adjustedPercent;
  129. if( threshDelta == 0. ) adjustedPercent = 1.;
  130. else adjustedPercent = ( percent - alignmentThresh ) / threshDelta;
  131. f = ( 0.5 - ( cos( adjustedPercent * PI_2 ) * -0.5 + 0.5 ) ) * delta;
  132. velocity += normalize( dir ) * f;
  133. }
  134. }
  135. }
  136. // this make tends to fly around than down or up
  137. // if (velocity.y > 0.) velocity.y *= (1. - 0.2 * delta);
  138. // Speed Limits
  139. if ( length( velocity ) > limit ) {
  140. velocity = normalize( velocity ) * limit;
  141. }
  142. gl_FragColor = vec4( velocity, 1.0 );
  143. }
  144. </script>
  145. <!-- Import maps polyfill -->
  146. <!-- Remove this when import maps will be widely supported -->
  147. <script async src="https://unpkg.com/[email protected]/dist/es-module-shims.js"></script>
  148. <script type="importmap">
  149. {
  150. "imports": {
  151. "three": "../build/three.module.js",
  152. "three/addons/": "./jsm/"
  153. }
  154. }
  155. </script>
  156. <script type="module">
  157. import * as THREE from 'three';
  158. import Stats from 'three/addons/libs/stats.module.js';
  159. import { GUI } from 'three/addons/libs/lil-gui.module.min.js';
  160. import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';
  161. import { GPUComputationRenderer } from 'three/addons/misc/GPUComputationRenderer.js';
  162. /* TEXTURE WIDTH FOR SIMULATION */
  163. const WIDTH = 64;
  164. const BIRDS = WIDTH * WIDTH;
  165. /* BAKE ANIMATION INTO TEXTURE and CREATE GEOMETRY FROM BASE MODEL */
  166. const BirdGeometry = new THREE.BufferGeometry();
  167. let textureAnimation, durationAnimation, birdMesh, materialShader, indicesPerBird;
  168. function nextPowerOf2( n ) {
  169. return Math.pow( 2, Math.ceil( Math.log( n ) / Math.log( 2 ) ) );
  170. }
  171. Math.lerp = function ( value1, value2, amount ) {
  172. amount = Math.max( Math.min( amount, 1 ), 0 );
  173. return value1 + ( value2 - value1 ) * amount;
  174. };
  175. const gltfs = [ 'models/gltf/Parrot.glb', 'models/gltf/Flamingo.glb' ];
  176. const colors = [ 0xccFFFF, 0xffdeff ];
  177. const sizes = [ 0.2, 0.1 ];
  178. const selectModel = Math.floor( Math.random() * gltfs.length );
  179. new GLTFLoader().load( gltfs[ selectModel ], function ( gltf ) {
  180. const animations = gltf.animations;
  181. durationAnimation = Math.round( animations[ 0 ].duration * 60 );
  182. const birdGeo = gltf.scene.children[ 0 ].geometry;
  183. const morphAttributes = birdGeo.morphAttributes.position;
  184. const tHeight = nextPowerOf2( durationAnimation );
  185. const tWidth = nextPowerOf2( birdGeo.getAttribute( 'position' ).count );
  186. indicesPerBird = birdGeo.index.count;
  187. const tData = new Float32Array( 4 * tWidth * tHeight );
  188. for ( let i = 0; i < tWidth; i ++ ) {
  189. for ( let j = 0; j < tHeight; j ++ ) {
  190. const offset = j * tWidth * 4;
  191. const curMorph = Math.floor( j / durationAnimation * morphAttributes.length );
  192. const nextMorph = ( Math.floor( j / durationAnimation * morphAttributes.length ) + 1 ) % morphAttributes.length;
  193. const lerpAmount = j / durationAnimation * morphAttributes.length % 1;
  194. if ( j < durationAnimation ) {
  195. let d0, d1;
  196. d0 = morphAttributes[ curMorph ].array[ i * 3 ];
  197. d1 = morphAttributes[ nextMorph ].array[ i * 3 ];
  198. if ( d0 !== undefined && d1 !== undefined ) tData[ offset + i * 4 ] = Math.lerp( d0, d1, lerpAmount );
  199. d0 = morphAttributes[ curMorph ].array[ i * 3 + 1 ];
  200. d1 = morphAttributes[ nextMorph ].array[ i * 3 + 1 ];
  201. if ( d0 !== undefined && d1 !== undefined ) tData[ offset + i * 4 + 1 ] = Math.lerp( d0, d1, lerpAmount );
  202. d0 = morphAttributes[ curMorph ].array[ i * 3 + 2 ];
  203. d1 = morphAttributes[ nextMorph ].array[ i * 3 + 2 ];
  204. if ( d0 !== undefined && d1 !== undefined ) tData[ offset + i * 4 + 2 ] = Math.lerp( d0, d1, lerpAmount );
  205. tData[ offset + i * 4 + 3 ] = 1;
  206. }
  207. }
  208. }
  209. textureAnimation = new THREE.DataTexture( tData, tWidth, tHeight, THREE.RGBAFormat, THREE.FloatType );
  210. textureAnimation.needsUpdate = true;
  211. const vertices = [], color = [], reference = [], seeds = [], indices = [];
  212. const totalVertices = birdGeo.getAttribute( 'position' ).count * 3 * BIRDS;
  213. for ( let i = 0; i < totalVertices; i ++ ) {
  214. const bIndex = i % ( birdGeo.getAttribute( 'position' ).count * 3 );
  215. vertices.push( birdGeo.getAttribute( 'position' ).array[ bIndex ] );
  216. color.push( birdGeo.getAttribute( 'color' ).array[ bIndex ] );
  217. }
  218. let r = Math.random();
  219. for ( let i = 0; i < birdGeo.getAttribute( 'position' ).count * BIRDS; i ++ ) {
  220. const bIndex = i % ( birdGeo.getAttribute( 'position' ).count );
  221. const bird = Math.floor( i / birdGeo.getAttribute( 'position' ).count );
  222. if ( bIndex == 0 ) r = Math.random();
  223. const j = ~ ~ bird;
  224. const x = ( j % WIDTH ) / WIDTH;
  225. const y = ~ ~ ( j / WIDTH ) / WIDTH;
  226. reference.push( x, y, bIndex / tWidth, durationAnimation / tHeight );
  227. seeds.push( bird, r, Math.random(), Math.random() );
  228. }
  229. for ( let i = 0; i < birdGeo.index.array.length * BIRDS; i ++ ) {
  230. const offset = Math.floor( i / birdGeo.index.array.length ) * ( birdGeo.getAttribute( 'position' ).count );
  231. indices.push( birdGeo.index.array[ i % birdGeo.index.array.length ] + offset );
  232. }
  233. BirdGeometry.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );
  234. BirdGeometry.setAttribute( 'birdColor', new THREE.BufferAttribute( new Float32Array( color ), 3 ) );
  235. BirdGeometry.setAttribute( 'color', new THREE.BufferAttribute( new Float32Array( color ), 3 ) );
  236. BirdGeometry.setAttribute( 'reference', new THREE.BufferAttribute( new Float32Array( reference ), 4 ) );
  237. BirdGeometry.setAttribute( 'seeds', new THREE.BufferAttribute( new Float32Array( seeds ), 4 ) );
  238. BirdGeometry.setIndex( indices );
  239. init();
  240. animate();
  241. } );
  242. let container, stats;
  243. let camera, scene, renderer;
  244. let mouseX = 0, mouseY = 0;
  245. let windowHalfX = window.innerWidth / 2;
  246. let windowHalfY = window.innerHeight / 2;
  247. const BOUNDS = 800, BOUNDS_HALF = BOUNDS / 2;
  248. let last = performance.now();
  249. let gpuCompute;
  250. let velocityVariable;
  251. let positionVariable;
  252. let positionUniforms;
  253. let velocityUniforms;
  254. function init() {
  255. container = document.createElement( 'div' );
  256. document.body.appendChild( container );
  257. camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 1, 3000 );
  258. camera.position.z = 350;
  259. scene = new THREE.Scene();
  260. scene.background = new THREE.Color( colors[ selectModel ] );
  261. scene.fog = new THREE.Fog( colors[ selectModel ], 100, 1000 );
  262. // LIGHTS
  263. const hemiLight = new THREE.HemisphereLight( colors[ selectModel ], 0xffffff, 1.6 );
  264. hemiLight.color.setHSL( 0.6, 1, 0.6 );
  265. hemiLight.groundColor.setHSL( 0.095, 1, 0.75 );
  266. hemiLight.position.set( 0, 50, 0 );
  267. scene.add( hemiLight );
  268. const dirLight = new THREE.DirectionalLight( 0x00CED1, 0.6 );
  269. dirLight.color.setHSL( 0.1, 1, 0.95 );
  270. dirLight.position.set( - 1, 1.75, 1 );
  271. dirLight.position.multiplyScalar( 30 );
  272. scene.add( dirLight );
  273. renderer = new THREE.WebGLRenderer( { antialias: true } );
  274. renderer.setPixelRatio( window.devicePixelRatio );
  275. renderer.setSize( window.innerWidth, window.innerHeight );
  276. container.appendChild( renderer.domElement );
  277. initComputeRenderer();
  278. stats = new Stats();
  279. container.appendChild( stats.dom );
  280. container.style.touchAction = 'none';
  281. container.addEventListener( 'pointermove', onPointerMove );
  282. window.addEventListener( 'resize', onWindowResize );
  283. const gui = new GUI();
  284. const effectController = {
  285. separation: 20.0,
  286. alignment: 20.0,
  287. cohesion: 20.0,
  288. freedom: 0.75,
  289. size: sizes[ selectModel ],
  290. count: Math.floor( BIRDS / 4 )
  291. };
  292. const valuesChanger = function () {
  293. velocityUniforms[ 'separationDistance' ].value = effectController.separation;
  294. velocityUniforms[ 'alignmentDistance' ].value = effectController.alignment;
  295. velocityUniforms[ 'cohesionDistance' ].value = effectController.cohesion;
  296. velocityUniforms[ 'freedomFactor' ].value = effectController.freedom;
  297. if ( materialShader ) materialShader.uniforms[ 'size' ].value = effectController.size;
  298. BirdGeometry.setDrawRange( 0, indicesPerBird * effectController.count );
  299. };
  300. valuesChanger();
  301. gui.add( effectController, 'separation', 0.0, 100.0, 1.0 ).onChange( valuesChanger );
  302. gui.add( effectController, 'alignment', 0.0, 100, 0.001 ).onChange( valuesChanger );
  303. gui.add( effectController, 'cohesion', 0.0, 100, 0.025 ).onChange( valuesChanger );
  304. gui.add( effectController, 'size', 0, 1, 0.01 ).onChange( valuesChanger );
  305. gui.add( effectController, 'count', 0, BIRDS, 1 ).onChange( valuesChanger );
  306. gui.close();
  307. initBirds( effectController );
  308. }
  309. function initComputeRenderer() {
  310. gpuCompute = new GPUComputationRenderer( WIDTH, WIDTH, renderer );
  311. if ( renderer.capabilities.isWebGL2 === false ) {
  312. gpuCompute.setDataType( THREE.HalfFloatType );
  313. }
  314. const dtPosition = gpuCompute.createTexture();
  315. const dtVelocity = gpuCompute.createTexture();
  316. fillPositionTexture( dtPosition );
  317. fillVelocityTexture( dtVelocity );
  318. velocityVariable = gpuCompute.addVariable( 'textureVelocity', document.getElementById( 'fragmentShaderVelocity' ).textContent, dtVelocity );
  319. positionVariable = gpuCompute.addVariable( 'texturePosition', document.getElementById( 'fragmentShaderPosition' ).textContent, dtPosition );
  320. gpuCompute.setVariableDependencies( velocityVariable, [ positionVariable, velocityVariable ] );
  321. gpuCompute.setVariableDependencies( positionVariable, [ positionVariable, velocityVariable ] );
  322. positionUniforms = positionVariable.material.uniforms;
  323. velocityUniforms = velocityVariable.material.uniforms;
  324. positionUniforms[ 'time' ] = { value: 0.0 };
  325. positionUniforms[ 'delta' ] = { value: 0.0 };
  326. velocityUniforms[ 'time' ] = { value: 1.0 };
  327. velocityUniforms[ 'delta' ] = { value: 0.0 };
  328. velocityUniforms[ 'testing' ] = { value: 1.0 };
  329. velocityUniforms[ 'separationDistance' ] = { value: 1.0 };
  330. velocityUniforms[ 'alignmentDistance' ] = { value: 1.0 };
  331. velocityUniforms[ 'cohesionDistance' ] = { value: 1.0 };
  332. velocityUniforms[ 'freedomFactor' ] = { value: 1.0 };
  333. velocityUniforms[ 'predator' ] = { value: new THREE.Vector3() };
  334. velocityVariable.material.defines.BOUNDS = BOUNDS.toFixed( 2 );
  335. velocityVariable.wrapS = THREE.RepeatWrapping;
  336. velocityVariable.wrapT = THREE.RepeatWrapping;
  337. positionVariable.wrapS = THREE.RepeatWrapping;
  338. positionVariable.wrapT = THREE.RepeatWrapping;
  339. const error = gpuCompute.init();
  340. if ( error !== null ) {
  341. console.error( error );
  342. }
  343. }
  344. function initBirds( effectController ) {
  345. const geometry = BirdGeometry;
  346. const m = new THREE.MeshStandardMaterial( {
  347. vertexColors: true,
  348. flatShading: true,
  349. roughness: 1,
  350. metalness: 0
  351. } );
  352. m.onBeforeCompile = ( shader ) => {
  353. shader.uniforms.texturePosition = { value: null };
  354. shader.uniforms.textureVelocity = { value: null };
  355. shader.uniforms.textureAnimation = { value: textureAnimation };
  356. shader.uniforms.time = { value: 1.0 };
  357. shader.uniforms.size = { value: effectController.size };
  358. shader.uniforms.delta = { value: 0.0 };
  359. let token = '#define STANDARD';
  360. let insert = /* glsl */`
  361. attribute vec4 reference;
  362. attribute vec4 seeds;
  363. attribute vec3 birdColor;
  364. uniform sampler2D texturePosition;
  365. uniform sampler2D textureVelocity;
  366. uniform sampler2D textureAnimation;
  367. uniform float size;
  368. uniform float time;
  369. `;
  370. shader.vertexShader = shader.vertexShader.replace( token, token + insert );
  371. token = '#include <begin_vertex>';
  372. insert = /* glsl */`
  373. vec4 tmpPos = texture2D( texturePosition, reference.xy );
  374. vec3 pos = tmpPos.xyz;
  375. vec3 velocity = normalize(texture2D( textureVelocity, reference.xy ).xyz);
  376. vec3 aniPos = texture2D( textureAnimation, vec2( reference.z, mod( time + ( seeds.x ) * ( ( 0.0004 + seeds.y / 10000.0) + normalize( velocity ) / 20000.0 ), reference.w ) ) ).xyz;
  377. vec3 newPosition = position;
  378. newPosition = mat3( modelMatrix ) * ( newPosition + aniPos );
  379. newPosition *= size + seeds.y * size * 0.2;
  380. velocity.z *= -1.;
  381. float xz = length( velocity.xz );
  382. float xyz = 1.;
  383. float x = sqrt( 1. - velocity.y * velocity.y );
  384. float cosry = velocity.x / xz;
  385. float sinry = velocity.z / xz;
  386. float cosrz = x / xyz;
  387. float sinrz = velocity.y / xyz;
  388. mat3 maty = mat3( cosry, 0, -sinry, 0 , 1, 0 , sinry, 0, cosry );
  389. mat3 matz = mat3( cosrz , sinrz, 0, -sinrz, cosrz, 0, 0 , 0 , 1 );
  390. newPosition = maty * matz * newPosition;
  391. newPosition += pos;
  392. vec3 transformed = vec3( newPosition );
  393. `;
  394. shader.vertexShader = shader.vertexShader.replace( token, insert );
  395. materialShader = shader;
  396. };
  397. birdMesh = new THREE.Mesh( geometry, m );
  398. birdMesh.rotation.y = Math.PI / 2;
  399. birdMesh.castShadow = true;
  400. birdMesh.receiveShadow = true;
  401. scene.add( birdMesh );
  402. }
  403. function fillPositionTexture( texture ) {
  404. const theArray = texture.image.data;
  405. for ( let k = 0, kl = theArray.length; k < kl; k += 4 ) {
  406. const x = Math.random() * BOUNDS - BOUNDS_HALF;
  407. const y = Math.random() * BOUNDS - BOUNDS_HALF;
  408. const z = Math.random() * BOUNDS - BOUNDS_HALF;
  409. theArray[ k + 0 ] = x;
  410. theArray[ k + 1 ] = y;
  411. theArray[ k + 2 ] = z;
  412. theArray[ k + 3 ] = 1;
  413. }
  414. }
  415. function fillVelocityTexture( texture ) {
  416. const theArray = texture.image.data;
  417. for ( let k = 0, kl = theArray.length; k < kl; k += 4 ) {
  418. const x = Math.random() - 0.5;
  419. const y = Math.random() - 0.5;
  420. const z = Math.random() - 0.5;
  421. theArray[ k + 0 ] = x * 10;
  422. theArray[ k + 1 ] = y * 10;
  423. theArray[ k + 2 ] = z * 10;
  424. theArray[ k + 3 ] = 1;
  425. }
  426. }
  427. function onWindowResize() {
  428. windowHalfX = window.innerWidth / 2;
  429. windowHalfY = window.innerHeight / 2;
  430. camera.aspect = window.innerWidth / window.innerHeight;
  431. camera.updateProjectionMatrix();
  432. renderer.setSize( window.innerWidth, window.innerHeight );
  433. }
  434. function onPointerMove( event ) {
  435. if ( event.isPrimary === false ) return;
  436. mouseX = event.clientX - windowHalfX;
  437. mouseY = event.clientY - windowHalfY;
  438. }
  439. //
  440. function animate() {
  441. requestAnimationFrame( animate );
  442. render();
  443. stats.update();
  444. }
  445. function render() {
  446. const now = performance.now();
  447. let delta = ( now - last ) / 1000;
  448. if ( delta > 1 ) delta = 1; // safety cap on large deltas
  449. last = now;
  450. positionUniforms[ 'time' ].value = now;
  451. positionUniforms[ 'delta' ].value = delta;
  452. velocityUniforms[ 'time' ].value = now;
  453. velocityUniforms[ 'delta' ].value = delta;
  454. if ( materialShader ) materialShader.uniforms[ 'time' ].value = now / 1000;
  455. if ( materialShader ) materialShader.uniforms[ 'delta' ].value = delta;
  456. velocityUniforms[ 'predator' ].value.set( 0.5 * mouseX / windowHalfX, - 0.5 * mouseY / windowHalfY, 0 );
  457. mouseX = 10000;
  458. mouseY = 10000;
  459. gpuCompute.compute();
  460. if ( materialShader ) materialShader.uniforms[ 'texturePosition' ].value = gpuCompute.getCurrentRenderTarget( positionVariable ).texture;
  461. if ( materialShader ) materialShader.uniforms[ 'textureVelocity' ].value = gpuCompute.getCurrentRenderTarget( velocityVariable ).texture;
  462. renderer.render( scene, camera );
  463. }
  464. </script>
  465. </body>
  466. </html>