examples/webgl_rtt.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - render-to-texture</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 {
				position: absolute;
				top: 0px; width: 100%;
				padding: 5px;
			}

			a {
				color: #ffffff;
			}

		</style>
	</head>
	<body>

		<div id="container"></div>
		<div id="info"><a href="http://threejs.org" target="_blank">three.js</a> render-to-texture webgl example</div>

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

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

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

			varying vec2 vUv;
			uniform sampler2D tDiffuse;

			void main() {

				gl_FragColor = texture2D( tDiffuse, vUv );

			}

		</script>

		<script id="fragment_shader_pass_1" type="x-shader/x-fragment">

			varying vec2 vUv;
			uniform float time;

			void main() {

				float r = vUv.x;
				if( vUv.y < 0.5 ) r = 0.0;
				float g = vUv.y;
				if( vUv.x < 0.5 ) g = 0.0;

				gl_FragColor = vec4( r, g, time, 1.0 );

			}

		</script>

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

			varying vec2 vUv;

			void main() {

				vUv = uv;
				gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );

			}

		</script>


		<script>

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

			var container, stats;

			var cameraRTT, camera, sceneRTT, sceneScreen, scene, renderer, zmesh1, zmesh2;

			var mouseX = 0, mouseY = 0;

			var windowHalfX = window.innerWidth / 2;
			var windowHalfY = window.innerHeight / 2;

			var rtTexture, material, quad;

			var delta = 0.01;

			init();
			animate();

			function init() {

				container = document.getElementById( 'container' );

				camera = new THREE.PerspectiveCamera( 30, window.innerWidth / window.innerHeight, 1, 10000 );
				camera.position.z = 100;

				cameraRTT = new THREE.OrthographicCamera( window.innerWidth / - 2, window.innerWidth / 2, window.innerHeight / 2, window.innerHeight / - 2, -10000, 10000 );
				cameraRTT.position.z = 100;

				//

				scene = new THREE.Scene();
				sceneRTT = new THREE.Scene();
				sceneScreen = new THREE.Scene();

				var light = new THREE.DirectionalLight( 0xffffff );
				light.position.set( 0, 0, 1 ).normalize();
				sceneRTT.add( light );

				light = new THREE.DirectionalLight( 0xffaaaa, 1.5 );
				light.position.set( 0, 0, -1 ).normalize();
				sceneRTT.add( light );

				rtTexture = new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight, { minFilter: THREE.LinearFilter, magFilter: THREE.NearestFilter, format: THREE.RGBFormat } );

				material = new THREE.ShaderMaterial( {

					uniforms: { time: { type: "f", value: 0.0 } },
					vertexShader: document.getElementById( 'vertexShader' ).textContent,
					fragmentShader: document.getElementById( 'fragment_shader_pass_1' ).textContent

				} );

				var materialScreen = new THREE.ShaderMaterial( {

					uniforms: { tDiffuse: { type: "t", value: rtTexture } },
					vertexShader: document.getElementById( 'vertexShader' ).textContent,
					fragmentShader: document.getElementById( 'fragment_shader_screen' ).textContent,

					depthWrite: false

				} );

				var plane = new THREE.PlaneGeometry( window.innerWidth, window.innerHeight );

				quad = new THREE.Mesh( plane, material );
				quad.position.z = -100;
				sceneRTT.add( quad );

				var geometry = new THREE.TorusGeometry( 100, 25, 15, 30 );

				var mat1 = new THREE.MeshPhongMaterial( { color: 0x555555, specular: 0xffaa00, shininess: 5 } );
				var mat2 = new THREE.MeshPhongMaterial( { color: 0x550000, specular: 0xff2200, shininess: 5 } );

				zmesh1 = new THREE.Mesh( geometry, mat1 );
				zmesh1.position.set( 0, 0, 100 );
				zmesh1.scale.set( 1.5, 1.5, 1.5 );
				sceneRTT.add( zmesh1 );

				zmesh2 = new THREE.Mesh( geometry, mat2 );
				zmesh2.position.set( 0, 150, 100 );
				zmesh2.scale.set( 0.75, 0.75, 0.75 );
				sceneRTT.add( zmesh2 );

				quad = new THREE.Mesh( plane, materialScreen );
				quad.position.z = -100;
				sceneScreen.add( quad );

				var n = 5,
					geometry = new THREE.SphereGeometry( 10, 64, 32 ),
					material2 = new THREE.MeshBasicMaterial( { color: 0xffffff, map: rtTexture } );

				for( var j = 0; j < n; j ++ ) {

					for( var i = 0; i < n; i ++ ) {

						mesh = new THREE.Mesh( geometry, material2 );

						mesh.position.x = ( i - ( n - 1 ) / 2 ) * 20;
						mesh.position.y = ( j - ( n - 1 ) / 2 ) * 20;
						mesh.position.z = 0;

						mesh.rotation.y = - Math.PI / 2;

						scene.add( mesh );

					}

				}

				renderer = new THREE.WebGLRenderer();
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.autoClear = false;

				container.appendChild( renderer.domElement );

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

				document.addEventListener( 'mousemove', onDocumentMouseMove, false );

			}

			function onDocumentMouseMove( event ) {

				mouseX = ( event.clientX - windowHalfX );
				mouseY = ( event.clientY - windowHalfY );

			}

			//

			function animate() {

				requestAnimationFrame( animate );

				render();
				stats.update();

			}

			function render() {

				var time = Date.now() * 0.0015;

				camera.position.x += ( mouseX - camera.position.x ) * .05;
				camera.position.y += ( - mouseY - camera.position.y ) * .05;

				camera.lookAt( scene.position );

				if ( zmesh1 && zmesh2 ) {

					zmesh1.rotation.y = - time;
					zmesh2.rotation.y = - time + Math.PI / 2;

				}

				if ( material.uniforms.time.value > 1 || material.uniforms.time.value < 0 ) {

					delta *= -1;

				}

				material.uniforms.time.value += delta;

				renderer.clear();

				// Render first scene into texture

				renderer.render( sceneRTT, cameraRTT, rtTexture, true );

				// Render full screen quad with generated texture

				renderer.render( sceneScreen, cameraRTT );

				// Render second scene to screen
				// (using first scene as regular texture)

				renderer.render( scene, camera );

			}

		</script>
	</body>
</html>