<!DOCTYPE html>
<html lang="en">
<head>
<title>three.js webgl - interactive cubes (gpu)</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 {
font-family: Monospace;
background-color: #f0f0f0;
margin: 0px;
overflow: hidden;
}
.info {
position: absolute;
background-color: black;
opacity: 0.8;
color: white;
text-align: center;
top: 0px;
width: 100%;
}
.info a {
color: #00ffff;
}
</style>
</head>
<body>
<div class="info">
<a href="http://threejs.org" target="_blank">three.js</a> webgl - gpu picking
</div>
<div id="container"></div>
<script src="../build/three.min.js"></script>
<script src="js/controls/TrackballControls.js"></script>
<script src="js/libs/stats.min.js"></script>
<script>
var container, stats;
var camera, controls, scene, renderer;
var pickingData = [], pickingTexture, pickingScene;
var objects = [];
var highlightBox;
var mouse = new THREE.Vector2();
var offset = new THREE.Vector3( 10, 10, 10 );
init();
animate();
function init() {
container = document.getElementById( "container" );
camera = new THREE.PerspectiveCamera( 70, window.innerWidth / window.innerHeight, 1, 10000 );
camera.position.z = 1000;
controls = new THREE.TrackballControls( camera );
controls.rotateSpeed = 1.0;
controls.zoomSpeed = 1.2;
controls.panSpeed = 0.8;
controls.noZoom = false;
controls.noPan = false;
controls.staticMoving = true;
controls.dynamicDampingFactor = 0.3;
scene = new THREE.Scene();
pickingScene = new THREE.Scene();
pickingTexture = new THREE.WebGLRenderTarget( window.innerWidth, window.innerHeight );
pickingTexture.minFilter = THREE.LinearFilter;
pickingTexture.generateMipmaps = false;
scene.add( new THREE.AmbientLight( 0x555555 ) );
var light = new THREE.SpotLight( 0xffffff, 1.5 );
light.position.set( 0, 500, 2000 );
scene.add( light );
var geometry = new THREE.Geometry(),
pickingGeometry = new THREE.Geometry(),
pickingMaterial = new THREE.MeshBasicMaterial( { vertexColors: THREE.VertexColors } ),
defaultMaterial = new THREE.MeshLambertMaterial({ color: 0xffffff, shading: THREE.FlatShading, vertexColors: THREE.VertexColors } );
function applyVertexColors( g, c ) {
g.faces.forEach( function( f ) {
var n = ( f instanceof THREE.Face3 ) ? 3 : 4;
for( var j = 0; j < n; j ++ ) {
f.vertexColors[ j ] = c;
}
} );
}
var geom = new THREE.BoxGeometry( 1, 1, 1 );
var color = new THREE.Color();
var matrix = new THREE.Matrix4();
var quaternion = new THREE.Quaternion();
for ( var i = 0; i < 5000; i ++ ) {
var position = new THREE.Vector3();
position.x = Math.random() * 10000 - 5000;
position.y = Math.random() * 6000 - 3000;
position.z = Math.random() * 8000 - 4000;
var rotation = new THREE.Euler();
rotation.x = Math.random() * 2 * Math.PI;
rotation.y = Math.random() * 2 * Math.PI;
rotation.z = Math.random() * 2 * Math.PI;
var scale = new THREE.Vector3();
scale.x = Math.random() * 200 + 100;
scale.y = Math.random() * 200 + 100;
scale.z = Math.random() * 200 + 100;
quaternion.setFromEuler( rotation, false );
matrix.compose( position, quaternion, scale );
// give the geom's vertices a random color, to be displayed
applyVertexColors( geom, color.setHex( Math.random() * 0xffffff ) );
geometry.merge( geom, matrix );
// give the geom's vertices a color corresponding to the "id"
applyVertexColors( geom, color.setHex( i ) );
pickingGeometry.merge( geom, matrix );
pickingData[ i ] = {
position: position,
rotation: rotation,
scale: scale
};
}
var drawnObject = new THREE.Mesh( geometry, defaultMaterial );
scene.add( drawnObject );
pickingScene.add( new THREE.Mesh( pickingGeometry, pickingMaterial ) );
highlightBox = new THREE.Mesh(
new THREE.BoxGeometry( 1, 1, 1 ),
new THREE.MeshLambertMaterial( { color: 0xffff00 }
) );
scene.add( highlightBox );
renderer = new THREE.WebGLRenderer( { antialias: true } );
renderer.setClearColor( 0xffffff );
renderer.setPixelRatio( window.devicePixelRatio );
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.sortObjects = false;
container.appendChild( renderer.domElement );
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
container.appendChild( stats.domElement );
renderer.domElement.addEventListener( 'mousemove', onMouseMove );
}
//
function onMouseMove( e ) {
mouse.x = e.clientX;
mouse.y = e.clientY;
}
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function pick() {
//render the picking scene off-screen
renderer.render( pickingScene, camera, pickingTexture );
//create buffer for reading single pixel
var pixelBuffer = new Uint8Array( 4 );
//read the pixel under the mouse from the texture
renderer.readRenderTargetPixels(pickingTexture, mouse.x, pickingTexture.height - mouse.y, 1, 1, pixelBuffer);
//interpret the pixel as an ID
var id = ( pixelBuffer[0] << 16 ) | ( pixelBuffer[1] << 8 ) | ( pixelBuffer[2] );
var data = pickingData[ id ];
if ( data) {
//move our highlightBox so that it surrounds the picked object
if ( data.position && data.rotation && data.scale ){
highlightBox.position.copy( data.position );
highlightBox.rotation.copy( data.rotation );
highlightBox.scale.copy( data.scale ).add( offset );
highlightBox.visible = true;
}
} else {
highlightBox.visible = false;
}
}
function render() {
controls.update();
pick();
renderer.render( scene, camera );
}
</script>
</body>
</html>