// Based on http://www.openprocessing.org/visuals/?visualID=6910
var mouseX = 0,
    mouseY = 0,
	windowHalfX = window.innerWidth / 2,
    windowHalfY = window.innerHeight / 2;
			var Boid = function() {
 
				var vector = new THREE.Vector3(),
				_acceleration, _width = 500, _height = 500, _depth = 200, _goal, _neighborhoodRadius = 100,
				_maxSpeed = 4, _maxSteerForce = 0.1, _avoidWalls = false;
 
				this.position = new THREE.Vector3();
				this.velocity = new THREE.Vector3();
				_acceleration = new THREE.Vector3();
 
				this.setGoal = function ( target ) {
 
					_goal = target;
 
				}
 
				this.setAvoidWalls = function ( value ) {
 
					_avoidWalls = value;
 
				}
 
				this.setWorldSize = function ( width, height, depth ) {
 
					_width = width;
					_height = height;vector
					_depth = depth;
 
				}
 
				this.run = function ( boids ) {
 
					if ( _avoidWalls ) {
 
						vector.set( - _width, this.position.y, this.position.z );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
						vector.set( _width, this.position.y, this.position.z );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
						vector.set( this.position.x, - _height, this.position.z );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
						vector.set( this.position.x, _height, this.position.z );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
						vector.set( this.position.x, this.position.y, - _depth );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
						vector.set( this.position.x, this.position.y, _depth );
						vector = this.avoid( vector );
						vector.multiplyScalar( 5 );
						_acceleration.addSelf( vector );
 
					}else {
 
						this.checkBounds();

					}
					
 
					if ( Math.random() > 0.5 ) {
 
						this.flock( boids );
 
					}
 
					this.move();
 
				}
 
				this.flock = function ( boids ) {
 
					if ( _goal ) {
 
						_acceleration.addSelf( this.reach( _goal, 0.005 ) );
 
					}
 
					_acceleration.addSelf( this.alignment( boids ) );
					_acceleration.addSelf( this.cohesion( boids ) );
					_acceleration.addSelf( this.separation( boids ) );
 
				}
 
				this.move = function () {
 
					this.velocity.addSelf( _acceleration );
 
					var l = this.velocity.length();
 
					if ( l > _maxSpeed ) {
 
						this.velocity.divideScalar( l / _maxSpeed );
 
					}
 
					this.position.addSelf( this.velocity );
					_acceleration.set( 0, 0, 0 );
 
				}
 
				this.checkBounds = function () {
 
					if ( this.position.x >   _width ) this.position.x = - _width;
					if ( this.position.x < - _width ) this.position.x =   _width;
					if ( this.position.y >   _height ) this.position.y = - _height;
					if ( this.position.y < - _height ) this.position.y =  _height;
					if ( this.position.z >  _depth ) this.position.z = - _depth;
					if ( this.position.z < - _depth ) this.position.z =  _depth;
 
				}
 
				//
 
				this.avoid = function ( target ) {
 
					var steer = new THREE.Vector3();
 
					steer.copy( this.position );
					steer.subSelf( target );
 
					steer.multiplyScalar( 1 / this.position.distanceToSquared( target ) );
 
					return steer;
 
				}
 
				this.repulse = function ( target ) {
 
					var distance = this.position.distanceTo( target );
 
					if ( distance < 150 ) {
 
						var steer = new THREE.Vector3();
 
						steer.sub( this.position, target );
						steer.multiplyScalar( 0.5 / distance );
 
						_acceleration.addSelf( steer );
 
					}
 
				}
 
				this.reach = function ( target, amount ) {
 
					var steer = new THREE.Vector3();
 
					steer.sub( target, this.position );
					steer.multiplyScalar( amount );
 
					return steer;
 
				}
 
				this.alignment = function ( boids ) {
 
					var boid, velSum = new THREE.Vector3(),
					count = 0;
 
					for ( var i = 0, il = boids.length; i < il; i++ ) {
 
						if ( Math.random() > 0.6 ) continue;
 
						boid = boids[ i ];
 
						distance = boid.position.distanceTo( this.position );
 
						if ( distance > 0 && distance <= _neighborhoodRadius ) {
 
							velSum.addSelf( boid.velocity );
							count++;
 
						}
 
					}
 
					if ( count > 0 ) {
 
						velSum.divideScalar( count );
 
						var l = velSum.length();
 
						if ( l > _maxSteerForce ) {
 
							velSum.divideScalar( l / _maxSteerForce );
 
						}
 
					}
 
					return velSum;
 
				}
 
				this.cohesion = function ( boids ) {
 
					var boid, distance,
					posSum = new THREE.Vector3(),
					steer = new THREE.Vector3(),
					count = 0;
 
					for ( var i = 0, il = boids.length; i < il; i ++ ) {
 
						if ( Math.random() > 0.6 ) continue;
 
						boid = boids[ i ];
						distance = boid.position.distanceTo( this.position );
 
						if ( distance > 0 && distance <= _neighborhoodRadius ) {
 
							posSum.addSelf( boid.position );
							count++;
 
						}
 
					}
 
					if ( count > 0 ) {
 
						posSum.divideScalar( count );
 
					}
 
					steer.sub( posSum, this.position );
 
					var l = steer.length();
 
					if ( l > _maxSteerForce ) {
 
						steer.divideScalar( l / _maxSteerForce );
 
					}
 
					return steer;
 
				}
 
				this.separation = function ( boids ) {
 
					var boid, distance,
					posSum = new THREE.Vector3(),
					repulse = new THREE.Vector3();
 
					for ( var i = 0, il = boids.length; i < il; i ++ ) {
 
						if ( Math.random() > 0.6 ) continue;
 
						boid = boids[ i ];
						distance = boid.position.distanceTo( this.position );
 
						if ( distance > 0 && distance <= _neighborhoodRadius ) {
 
							repulse.sub( this.position, boid.position );
							repulse.normalize();
							repulse.divideScalar( distance );
							posSum.addSelf( repulse );
 
						}
 
					}
 
					return posSum;
 
				}
 
			}
 
 
			var SCREEN_WIDTH = window.innerWidth,
			SCREEN_HEIGHT = window.innerHeight,
			SCREEN_WIDTH_HALF = SCREEN_WIDTH  / 2,
			SCREEN_HEIGHT_HALF = SCREEN_HEIGHT / 2;
 
			var camera, scene, renderer,group,
			birds, bird;
 
			var boid, boids;
 
			var stats;
 
			init();
			animate();
 
			function init() {
 
				camera = new THREE.Camera( 75, SCREEN_WIDTH / SCREEN_HEIGHT, 1, 10000 );
				camera.position.z = 450;
				
 
				scene = new THREE.Scene();
 				group = new THREE.Object3D();
				 scene.addObject(group);
				 
				birds = [];
				boids = [];
 
				for ( var i = 0; i < 75; i ++ ) {
 
					boid = boids[ i ] = new Boid();
					boid.position.x = Math.random() * 400 - 200;
					boid.position.y = Math.random() * -400 - 200;
					boid.position.z = Math.random() * 400 - 200;
					boid.velocity.x = Math.random() * 2 - 1;
					boid.velocity.y = Math.random() * 2 - 1;
					boid.velocity.z = Math.random() * 2 - 1;
					boid.setAvoidWalls( true );
					boid.setWorldSize( 1000, 1000, 1000 );
 
					bird = birds[ i ] = new THREE.Mesh( new Bird(), new THREE.MeshBasicMaterial( { color:0x222222 } ) );
					bird.phase = Math.floor( Math.random() * 62.83 );
					bird.position = boids[ i ].position;
					bird.doubleSided = true;
					// bird.scale.x = bird.scale.y = bird.scale.z = 10;
					scene.addObject( bird );
 
 
				}
 
				renderer = new THREE.CanvasRenderer();
				//renderer = new THREE.WebGLRenderer();
				//renderer.autoClear = true;
				renderer.setSize( SCREEN_WIDTH, SCREEN_HEIGHT );
 
				document.addEventListener( 'mousemove', onDocumentMouseMove, false );
				//document.body.appendChild( renderer.domElement );
				document.getElementById('background').appendChild(renderer.domElement);
				
				material = new THREE.ParticleCircleMaterial({
					color: 0xffffff,
					opacity: 1
				});
			
				for (var i = 0; i < 250; i++) {
			
					particle = new THREE.Particle(material);
					particle.position.x = Math.random() * 2 - 1;
					particle.position.y = Math.random() * 2 - 1;
					particle.position.z = Math.random() * 2 - 1;
			
					particle.position.normalize();
					particle.position.multiplyScalar(Math.random() * 10 + 1050);
			
					//scene.addObject(particle);
			
				}
				
			
				function createCloud(imgS,w,h) {
			
					var canvas = document.createElement('canvas');
					canvas.width = w;
					canvas.height = h;
			
					var context = canvas.getContext('2d');
					var img = new Image();
					img.onload = function () {
						context.drawImage(img, 0, 0, w, h);
					};
					img.src = imgS;
			
					return canvas;
			
				}
				
				
 		
			}
			
 
			function onDocumentMouseMove( event ) {
 
				var vector = new THREE.Vector3( event.clientX - SCREEN_WIDTH_HALF, - event.clientY + SCREEN_HEIGHT_HALF, 0 );
 
				for ( var i = 0, il = boids.length; i < il; i++ ) {
 
					boid = boids[ i ];
 
					vector.z = boid.position.z;
 
					boid.repulse( vector );
 
				}
				mouseX = event.clientX - windowHalfX;
				mouseY = event.clientY - windowHalfY;
 
			}
 
			//
 
			function animate() {
 				 
				requestAnimationFrame( animate );
 
				render();
				
 
			}
 
			function render() {
				
 				//camera.position.x += (mouseX - camera.position.x) * .02;
            	//camera.position.y += (-mouseY + 5 - camera.position.y) * .02;
				//camera.position.z += (mouseX - camera.position.z) * .02;
				for ( var i = 0, il = birds.length; i < il; i++ ) {
 
					boid = boids[ i ];
					boid.run( boids );
 
					bird = birds[ i ];
 
					color = bird.materials[ 0 ].color;
					color.r = color.g = color.b = ( 500 - bird.position.z ) / 1000;
					color.updateHex();
 
					bird.rotation.y = Math.atan2( - boid.velocity.z, boid.velocity.x );
					bird.rotation.z = Math.asin( boid.velocity.y / boid.velocity.length() );
 
					bird.phase = ( bird.phase + ( Math.max( 0, bird.rotation.z ) + 0.1 )  ) % 62.83;
					bird.geometry.vertices[ 5 ].position.y = bird.geometry.vertices[ 4 ].position.y = Math.sin( bird.phase ) * 5;
 
				}
 				
				renderer.render( scene, camera );
 
			}