threex
Version:
Game Extensions for three.js http://www.threejsgames.com/extensions/
141 lines (127 loc) • 4.37 kB
HTML
<!DOCTYPE html>
<script src="../../../vendor/three.js/build/three.min.js"></script>
<body style='margin: 0px; background-color: #bbbbbb;overflow: hidden;'>
<script>
var renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );
var updateFcts = [];
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 1000 );
camera.position.z = 3;
renderer.setClearColor('black', 1)
var geometry = new THREE.SphereGeometry( 1 );
var material = new THREE.MeshNormalMaterial();
var mesh = new THREE.Mesh( geometry, material );
mesh.scale.multiplyScalar(0.1)
scene.add( mesh );
updateFcts.push(function(delta, now){
var angle = 0.05 * now * Math.PI * 2;
mesh.position.x = Math.cos(angle*3.0) * 2
mesh.position.y = Math.sin(angle*1.3) * 1
emitter.emitThrottle(mesh.position, 120)
emitter.emitThrottle(mesh.position, 120)
})
var emitter = new blueTrailEmitter(scene)
updateFcts.push(function(delta, now){
emitter.update(delta, now)
})
//////////////////////////////////////////////////////////////////////////////////
// render the scene //
//////////////////////////////////////////////////////////////////////////////////
updateFcts.push(function(){
renderer.render( scene, camera );
})
//////////////////////////////////////////////////////////////////////////////////
// loop runner //
//////////////////////////////////////////////////////////////////////////////////
var lastTimeMsec= null
requestAnimationFrame(function animate(nowMsec){
// keep looping
requestAnimationFrame( animate );
// measure time
lastTimeMsec = lastTimeMsec || (nowMsec-1000/60)
var deltaMsec = Math.min(200, nowMsec - lastTimeMsec)
lastTimeMsec = nowMsec
// call each update function
updateFcts.forEach(function(updateFn){
updateFn(deltaMsec/1000, nowMsec/1000)
})
})
//////////////////////////////////////////////////////////////////////////////////
// comment //
//////////////////////////////////////////////////////////////////////////////////
function blueTrailEmitter(container){
var texture = THREE.ImageUtils.loadTexture('images/blue_particle.jpg')
var maxAge = 1;
var tweenOpacity= createTweenMidi(maxAge, 0.33*maxAge, 0.33*maxAge);
var tweenScale = (function(){
var tweenMidi = createTweenMidi(maxAge, 0.2*maxAge, 0.2*maxAge);
return function(age){
return (1 + 1 * tweenMidi(age)) * 0.2
}
})();
var updateFcts = []
var prevPosition= null;
this.emit = function(position){
// init sprite material
var material = new THREE.SpriteMaterial({
map : texture,
useScreenCoordinates : false,
color : 0xAA4488,
transparent : true,
blending : THREE.AdditiveBlending
})
// init sprite
var sprite = new THREE.Sprite(material)
//sprite.rotation = Math.random() * Math.PI*2
sprite.position.copy( position )
container.add( sprite )
// compute velocity
prevPosition = prevPosition || position.clone();
var velocity = position.clone().sub(prevPosition).normalize();
prevPosition.copy( position )
// start a little bit behind the container
sprite.position.add( velocity.clone().multiplyScalar(-0.1) )
// init pattern
sprite.scale.set(1,1,1).multiplyScalar( tweenScale(0) )
material.opacity= tweenOpacity(0)
var birthDate = Date.now()/1000;
updateFcts.push(function callback(delta, now){
var age = Date.now()/1000 - birthDate;
if( age >= maxAge ){
sprite.parent.remove(sprite)
updateFcts.splice(updateFcts.indexOf(callback),1)
return;
}
sprite.scale.set(1,1,1).multiplyScalar( tweenScale(age) )
material.opacity= tweenOpacity(age)
})
}
var lastEmit = 0;
this.emitThrottle= function(position, rate){
// rate limiter emition
var now = Date.now()/1000
if( rate === 0 || now - lastEmit < 1/rate ) return;
lastEmit = now;
// emit now
this.emit(position)
}
this.update = function(delta, now){
updateFcts.forEach(function(updateFct){
updateFct(delta, now)
})
}
function createTweenMidi(maxAge, attackTime, releaseTime){
return function(age){
if( age < attackTime ){
return age / attackTime
}else if( age < maxAge - releaseTime ){
return 1;
}else{
return (maxAge - age) / releaseTime
}
}
}
}
</script></body>