Particle3D=function(material){
    THREE.Particle.call(this,material);
    this.velocity=new THREE.Vector3(0,-8,0);
    this.velocity.rotateX(randomRange(-45,45));
    this.velocity.rotateY(randomRange(0,360));
    this.gravity=new THREE.Vector3(0,0,0);
    this.drag=1;
};
Particle3D.prototype=new THREE.Particle();
Particle3D.prototype.constructor=Particle3D;
Particle3D.prototype.updatePhysics=function(){
    this.velocity.multiplyScalar(this.drag);
    this.velocity.addSelf(this.gravity);
    this.position.addSelf(this.velocity);
}
var TO_RADIANS=Math.PI/180;
THREE.Vector3.prototype.rotateY=function(angle){
    cosRY=Math.cos(angle*TO_RADIANS);
    sinRY=Math.sin(angle*TO_RADIANS);
    var tempz=this.z;;
    var tempx=this.x;
    this.x=(tempx*cosRY)+(tempz*sinRY);
    this.z=(tempx*-sinRY)+(tempz*cosRY);
}
THREE.Vector3.prototype.rotateX=function(angle){
    cosRY=Math.cos(angle*TO_RADIANS);
    sinRY=Math.sin(angle*TO_RADIANS);
    var tempz=this.z;;
    var tempy=this.y;
    this.y=(tempy*cosRY)+(tempz*sinRY);
    this.z=(tempy*-sinRY)+(tempz*cosRY);
}
THREE.Vector3.prototype.rotateZ=function(angle){
    cosRY=Math.cos(angle*TO_RADIANS);
    sinRY=Math.sin(angle*TO_RADIANS);
    var tempx=this.x;;
    var tempy=this.y;
    this.y=(tempy*cosRY)+(tempx*sinRY);
    this.x=(tempy*-sinRY)+(tempx*cosRY);
}
function randomRange(min,max){
    return((Math.random()*(max-min))+ min);
}
var SCREEN_WIDTH = window.innerWidth;
var SCREEN_HEIGHT = window.innerHeight;

var container;

var particle;

var camera;
var scene;
var renderer;

var mouseX = 0;
var mouseY = 0;

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

var particles = []; 
var particleImage = new Image();//THREE.ImageUtils.loadTexture( "img/ParticleSmoke.png" );
particleImage.src = 'https://cdn.yimian.xyz/xuehua/ParticleSmoke.png'; 



function init() {

    container = document.createElement('div');
    document.body.appendChild(container);

    camera = new THREE.PerspectiveCamera( 75, SCREEN_WIDTH / SCREEN_HEIGHT, 1, 10000 );
    camera.position.z = 1000;

    scene = new THREE.Scene();
    scene.add(camera);
        
    renderer = new THREE.CanvasRenderer();
    renderer.setSize(SCREEN_WIDTH, SCREEN_HEIGHT);
    var material = new THREE.ParticleBasicMaterial( { map: new THREE.Texture(particleImage) } );
        
    for (var i = 0; i < 500; i++) {

        particle = new Particle3D( material);
        particle.position.x = Math.random() * 2000 - 1000;
        particle.position.y = Math.random() * 2000 - 1000;
        particle.position.z = Math.random() * 2000 - 1000;
        particle.scale.x = particle.scale.y =  1;
        scene.add( particle );
        
        particles.push(particle); 
    }

    container.appendChild( renderer.domElement );


    document.addEventListener( 'mousemove', onDocumentMouseMove, false );
    document.addEventListener( 'touchstart', onDocumentTouchStart, false );
    document.addEventListener( 'touchmove', onDocumentTouchMove, false );
    
    setInterval( loop, 1000 / 60 );
    
}

function onDocumentMouseMove( event ) {

    mouseX = event.clientX - windowHalfX;
    mouseY = event.clientY - windowHalfY;
}

function onDocumentTouchStart( event ) {

    if ( event.touches.length == 1 ) {

        event.preventDefault();

        mouseX = event.touches[ 0 ].pageX - windowHalfX;
        mouseY = event.touches[ 0 ].pageY - windowHalfY;
    }
}

function onDocumentTouchMove( event ) {

    if ( event.touches.length == 1 ) {

        event.preventDefault();

        mouseX = event.touches[ 0 ].pageX - windowHalfX;
        mouseY = event.touches[ 0 ].pageY - windowHalfY;
    }
}

//

function loop() {

for(var i = 0; i<particles.length; i++)
    {

        var particle = particles[i]; 
        particle.updatePhysics(); 

        with(particle.position)
        {
            if(y<-1000) y+=2000; 
            if(x>1000) x-=2000; 
            else if(x<-1000) x+=2000; 
            if(z>1000) z-=2000; 
            else if(z<-1000) z+=2000; 
        }               
    }

    camera.position.x += ( mouseX - camera.position.x ) * 0.05;
    camera.position.y += ( - mouseY - camera.position.y ) * 0.05;
    camera.lookAt(scene.position); 

    renderer.render( scene, camera );

    
}