threejs four major components: the scene, geometry, camera, the renderer. The following figure shows the first program, explain See note.
<!DOCTYPE html>
<html>
<head>
<title>第一个threejs</title>
<script src="three.js"></script>
</head>
<body>
</body>
<script>
var scene = new THREE.Scene();
//新建一个场景
var camera = new THREE.PerspectiveCamera(75,window.innerWidth/window.innerHeight,0.1,1000);
//新建一个透视相机
var renderer = new THREE.WebGLRenderer();
//新建一个渲染器
renderer.setSize(window.innerWidth,window.innerHeight);
//给渲染器设置大小，设置整个页面大小
document.body.appendChild(renderer.domElement);
//将渲染器加入页面
var geometry = new THREE.BoxGeometry();
var material = new THREE.MeshBasicMaterial({color:0x00ff00});
//创建一个立方体，以及创建一个材质
var cube = new THREE.Mesh(geometry,material);
//将材质和立方体组合，得到一个cube
scene.add(cube);
//将几何体加入场景
camera.position.z = 10;//近大远小
//设置相机距离原点的距离，相机距离原点越小，那么见到的原点处的几何体越大
//相机距离原点的距离越大，几何体越小
function render(){
requestAnimationFrame(render);
cube.rotation.y += 0.01;
cube.rotation.x += 0.01;
renderer.render(scene,camera);
}
//重复渲染，使几何体旋转
render();
</script>
</html>The figure is the distance from the origin to the camera to see 10 geometry, in theory, should be 1 hour, also more so than the actual distance.
