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涉及的知识点博主已经从three源码库里面摘要出来放在对应的注释里面
今天学习Helper里面的FaceNormalsHelper助手！
顺便加入了鼠标控制相机的组件OrbitControls，不懂可以先忽略！
效果图：
<html>
<head>
<title>Helper06-FaceNormalsHelper(法向助手)</title>
<style>
body {
margin: 0;
}
canvas {
width: 100%;
height: 100%
}
</style>
</head>
<body>
<script src="../../../build/three.js"></script>
<script src="../../js/controls/OrbitControls.js"></script>
<script>
var camera, scene, renderer, geometry, material, animate, controls; //常用变量
var cube, light,helper; //自定义对象变量
var target = new THREE.Vector3(0, 0, 0);
init();
animate();
function init() {
scene = new THREE.Scene();
scene.background = new THREE.Color(0xcfcfcf);
camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.set(0, 0, 150);
camera.lookAt(target);
camera.updateProjectionMatrix(); //相机更新
// DirectionalLight( color, intensity )
light = new THREE.DirectionalLight(0xFFFFFF,2);
light.position.set(20,20,50);
renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
//OrbitControls控件操作模块
controls = new THREE.OrbitControls(camera, renderer.domElement);
controls.addEventListener('change', function () {
renderer.render(scene, camera);
});
// BoxGeometry( width, height, depth, widthSegments, heightSegments, depthSegments )
geometry = new THREE.BoxGeometry(40, 40, 40,3,3,3);
material = new THREE.MeshBasicMaterial({
color: 0xcfffff,
wireframe: false
}); //wireframe默认为false
cube = new THREE.Mesh(geometry, material);
// FaceNormalsHelper( object, size, hex, linewidth )
helper = new THREE.FaceNormalsHelper( cube, 20, 0x00ffcc, 1 );
// helper = new THREE.VertexNormalsHelper( cube, 20, 0x00ffcc, 1 );
scene.add(cube,helper);
}
function animate() {
requestAnimationFrame(animate);
controls.update();
cube.rotation.x += 0.01;
if ( helper ) helper.update();//判断是否有法向助手，有则更新
renderer.render(scene, camera);
};
</script>
</body>
</html>