<!DOCTYPE html>
<html>
<head>
<title>Example 09.03 - Animation tween </title>
<script type="text/javascript" src="../libs/three.js"></script>
<script type="text/javascript" src="../libs/PLYLoader.js"></script>
<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<script type="text/javascript" src="../libs/tween.min.js"></script>
<style>
body {
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin: 0;
overflow: hidden;
}
</style>
</head>
<body>
<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>
<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">
// once everything is loaded, we run our Three.js stuff.
function init() {
var stats = initStats();
// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(new THREE.Color(0x000, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled = true;
// position and point the camera to the center of the scene
camera.position.x = 10;
camera.position.y = 10;
camera.position.z = 10;
camera.lookAt(new THREE.Vector3(0, -2, 0));
// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(20, 20, 20);
scene.add(spotLight);
// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);
// call the render function
var step = 0;
// setup the control gui
var controls = new function() {
// we need the first child, since it's a multimaterial
};
var pointCloud = new THREE.Object3D();
var loadedGeometry;
// create a tween
// http://sole.github.io/tween.js/examples/03_graphs.html
var posSrc = {
pos: 1
};
// 这个库可以用来定义某个属性在两个值之间的过渡，自动计算出起始值和结束值之间的所有中间值。这个过程叫补间。
// 这个补间定义的是如何从1过渡到0
var tween = new TWEEN.Tween(posSrc).to({
pos: 0
}, 5000);
tween.easing(TWEEN.Easing.Sinusoidal.InOut);
//这个补间定义的是如何从0过渡到1
var tweenBack = new TWEEN.Tween(posSrc).to({
pos: 1
}, 5000);
tweenBack.easing(TWEEN.Easing.Sinusoidal.InOut);
// 通过chain函数，我们可以让这两个补间首尾相连。这样在启动动画之后，程序就会在这两个补间之间循环。
tween.chain(tweenBack);
tweenBack.chain(tween);
// 遍历粒子系统的所有顶点，并用补间提供的位置更新顶点的位置。
var onUpdate = function() {
var count = 0;
var pos = this.pos;
loadedGeometry.vertices.forEach(function(e) {
var newY = ((e.y + 3.22544) * pos) - 3.22544;
pointCloud.geometry.vertices[count++].set(e.x, newY, e.z);
});
pointCloud.sortParticles = true;
};
tween.onUpdate(onUpdate);
tweenBack.onUpdate(onUpdate);
var gui = new dat.GUI();
var loader = new THREE.PLYLoader();
loader.load("../assets/models/test.ply", function(geometry) {
loadedGeometry = geometry.clone();
var material = new THREE.PointCloudMaterial({
color: 0xffffff,
size: 0.4,
opacity: 0.6,
transparent: true,
blending: THREE.AdditiveBlending,
map: generateSprite()
});
pointCloud = new THREE.PointCloud(geometry, material);
pointCloud.sortParticles = true;
// 补间动画会在模型加载完毕时启动，所以我们在末尾调用start()函数
tween.start();
scene.add(pointCloud);
});
render();
// from THREE.js examples
function generateSprite() {
var canvas = document.createElement('canvas');
canvas.width = 16;
canvas.height = 16;
var context = canvas.getContext('2d');
var gradient = context.createRadialGradient(canvas.width / 2, canvas.height / 2, 0, canvas.width / 2, canvas.height / 2, canvas.width / 2);
gradient.addColorStop(0, 'rgba(255,255,255,1)');
gradient.addColorStop(0.2, 'rgba(0,255,255,1)');
gradient.addColorStop(0.4, 'rgba(0,0,64,1)');
gradient.addColorStop(1, 'rgba(0,0,0,1)');
context.fillStyle = gradient;
context.fillRect(0, 0, canvas.width, canvas.height);
var texture = new THREE.Texture(canvas);
texture.needsUpdate = true;
return texture;
}
function render() {
stats.update();
// 告知three.js库什么时候应该刷新已知的所有补间，为此可以调用TWEEN.update()
TWEEN.update();
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}
function initStats() {
var stats = new Stats();
stats.setMode(0); // 0: fps, 1: ms
// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left = '0px';
stats.domElement.style.top = '0px';
document.getElementById("Stats-output").appendChild(stats.domElement);
return stats;
}
}
window.onload = init;
</script>
</body>
</html>