examples/webgl_custom_attributes_particles2.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - custom attributes [particles][billboards]</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<style>
			body {
				color: #ffffff;
				font-family:Monospace;
				font-size:13px;
				text-align:center;
				font-weight: bold;

				background-color: #000000;
				margin: 0px;
				overflow: hidden;
			}
			#info {
				color: #fff;
				position: absolute;
				top: 0px; width: 100%;
				padding: 5px;
				z-index:100;
			}

		</style>
	</head>

	<body>
		<div id="info"><a href="http://threejs.org" target="_blank">three.js</a> - custom attributes example - particles - billboards</div>
		<div id="container"></div>

		<script src="../build/three.min.js"></script>

		<script src="js/Detector.js"></script>
		<script src="js/libs/stats.min.js"></script>

		<script type="x-shader/x-vertex" id="vertexshader">

			attribute float size;
			attribute vec3 ca;

			varying vec3 vColor;

			void main() {

				vColor = ca;

				vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );

				//gl_PointSize = size;
				gl_PointSize = size * ( 300.0 / length( mvPosition.xyz ) );

				gl_Position = projectionMatrix * mvPosition;

			}

		</script>

		<script type="x-shader/x-fragment" id="fragmentshader">

			uniform vec3 color;
			uniform sampler2D texture;

			varying vec3 vColor;

			void main() {

				gl_FragColor = vec4( color * vColor, 1.0 );
				gl_FragColor = gl_FragColor * texture2D( texture, gl_PointCoord );

			}

		</script>


		<script>

		if ( ! Detector.webgl ) Detector.addGetWebGLMessage();

		var renderer, scene, camera, stats;

		var sphere, uniforms, attributes;

		var vc1;

		var WIDTH = window.innerWidth;
		var HEIGHT = window.innerHeight;

		init();
		animate();

		function init() {

			camera = new THREE.PerspectiveCamera( 45, WIDTH / HEIGHT, 1, 10000 );
			camera.position.z = 300;

			scene = new THREE.Scene();

			attributes = {

				size: {	type: 'f', value: [] },
				ca:   {	type: 'c', value: [] }

			};

			uniforms = {

				amplitude: { type: "f", value: 1.0 },
				color:     { type: "c", value: new THREE.Color( 0xffffff ) },
				texture:   { type: "t", value: THREE.ImageUtils.loadTexture( "textures/sprites/disc.png" ) },

			};

			uniforms.texture.value.wrapS = uniforms.texture.value.wrapT = THREE.RepeatWrapping;

			var shaderMaterial = new THREE.ShaderMaterial( {

				uniforms: 		uniforms,
				attributes:     attributes,
				vertexShader:   document.getElementById( 'vertexshader' ).textContent,
				fragmentShader: document.getElementById( 'fragmentshader' ).textContent

			});


			var radius = 100, segments = 68, rings = 38;
			var geometry = new THREE.SphereGeometry( radius, segments, rings );

			vc1 = geometry.vertices.length;

			var geometry2 = new THREE.CubeGeometry( 0.8 * radius, 0.8 * radius, 0.8 * radius, 10, 10, 10 );

			THREE.GeometryUtils.merge( geometry, geometry2 );

			sphere = new THREE.ParticleSystem( geometry, shaderMaterial );

			sphere.dynamic = true;
			sphere.sortParticles = true;

			var vertices = sphere.geometry.vertices;
			var values_size = attributes.size.value;
			var values_color = attributes.ca.value;

			for( var v = 0; v < vertices.length; v++ ) {

				values_size[ v ] = 10;
				values_color[ v ] = new THREE.Color( 0xffffff );

				if ( v < vc1 ) {

					values_color[ v ].setHSV( 0.01 + 0.1 * ( v / vc1 ), 0.99, ( vertices[ v ].y + radius ) / ( 2 *radius ) );

				} else {

					values_size[ v ] = 40;
					values_color[ v ].setHSV( 0.6, 0.75, 0.5 + vertices[ v ].y / ( 0.8 * radius ) );

				}

			}

			scene.add( sphere );

			renderer = new THREE.WebGLRenderer( { clearColor: 0x000000, clearAlpha: 1 } );
			renderer.setSize( WIDTH, HEIGHT );

			var container = document.getElementById( 'container' );
			container.appendChild( renderer.domElement );

			stats = new Stats();
			stats.domElement.style.position = 'absolute';
			stats.domElement.style.top = '0px';
			container.appendChild( stats.domElement );

			//

			window.addEventListener( 'resize', onWindowResize, false );

		}

		function onWindowResize() {

			camera.aspect = window.innerWidth / window.innerHeight;
			camera.updateProjectionMatrix();

			renderer.setSize( window.innerWidth, window.innerHeight );

		}

		function animate() {

			requestAnimationFrame( animate );

			render();
			stats.update();

		}

		function render() {

			var time = Date.now() * 0.005;

			sphere.rotation.y = 0.02 * time;
			sphere.rotation.z = 0.02 * time;

			for( var i = 0; i < attributes.size.value.length; i ++ ) {

				if ( i < vc1 )
					attributes.size.value[ i ] = 16 + 12 * Math.sin( 0.1 * i + time );


			}

			attributes.size.needsUpdate = true;

			renderer.render( scene, camera );

		}


	</script>

</body>

</html>