用场景对three.js进行渲染：场景、相机、渲染器

const scene = new THREE.Scene();
const camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 0.1, 1000 );const renderer = new THREE.WebGLRenderer();
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );

场景

function Scene() {Object3D.call( this );this.type = 'Scene';this.background = null;this.fog = null;this.overrideMaterial = null;this.autoUpdate = true; // checked by the renderer}

透视摄影机

参数解析：

• fov: 视野角度（FOV）。视野角度就是无论在什么时候，你所能在显示器上看到的场景的范围，它的单位是角度(与弧度区分开)。
• aspect: 长宽比（aspect ratio）。 也就是你用一个物体的宽除以它的高的值。比如说，当你在一个宽屏电视上播放老电影时，可以看到图像仿佛是被压扁的。
• near: 近截面（near）
• far: 远截面（far）

function PerspectiveCamera( fov, aspect, near, far ) {Camera.call( this );this.type = 'PerspectiveCamera';this.fov = fov !== undefined ? fov : 50;this.zoom = 1;this.near = near !== undefined ? near : 0.1;this.far = far !== undefined ? far : 2000;this.focus = 10;this.aspect = aspect !== undefined ? aspect : 1;this.view = null;this.filmGauge = 35;	// width of the film (default in millimeters)this.filmOffset = 0;	// horizontal film offset (same unit as gauge)this.updateProjectionMatrix();}

渲染器

function WebGLRenderer( parameters ) {console.log( 'THREE.WebGLRenderer', REVISION );parameters = parameters || {};//...
}

浅试

创建一个渲染场景，没有物体

创建一个物体

const geometry = new THREE.BoxGeometry( 1, 1, 1 );
const material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );
const cube = new THREE.Mesh( geometry, material );
scene.add( cube );camera.position.z = 5;

立方体(BoxGeometry)

参数解析

• width ：X轴上面的宽度，默认值为1。
• height ：Y轴上面的高度，默认值为1。
• depth ：Z轴上面的深度，默认值为1。
• widthSegments ：可选）宽度的分段数，默认值是1。
• heightSegments ：（可选）高度的分段数，默认值是1。
• depthSegments ：可选）深度的分段数，默认值是1

function BoxGeometry( width, height, depth, widthSegments, heightSegments, depthSegments ) {Geometry.call( this );this.type = 'BoxGeometry';this.parameters = {width: width,height: height,depth: depth,widthSegments: widthSegments,heightSegments: heightSegments,depthSegments: depthSegments};this.fromBufferGeometry( new BoxBufferGeometry( width, height, depth, widthSegments, heightSegments, depthSegments ) );this.mergeVertices();}

材质

function MeshBasicMaterial( parameters ) {Material.call( this );this.type = 'MeshBasicMaterial';this.color = new Color( 0xffffff ); // emissivethis.map = null;this.lightMap = null;this.lightMapIntensity = 1.0;this.aoMap = null;this.aoMapIntensity = 1.0;this.specularMap = null;this.alphaMap = null;this.envMap = null;this.combine = MultiplyOperation;this.reflectivity = 1;this.refractionRatio = 0.98;this.wireframe = false;this.wireframeLinewidth = 1;this.wireframeLinecap = 'round';this.wireframeLinejoin = 'round';this.skinning = false;this.morphTargets = false;this.lights = false;this.setValues( parameters );}

网格

function Mesh( geometry, material ) {Object3D.call( this );this.type = 'Mesh';this.geometry = geometry !== undefined ? geometry : new BufferGeometry();this.material = material !== undefined ? material : new MeshBasicMaterial( { color: Math.random() * 0xffffff } );this.drawMode = TrianglesDrawMode;this.updateMorphTargets();}

物品渲染在场景上

// 创建场景
const scene = new THREE.Scene();// 创建相机
const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 1, 1000);// 渲染
const renderer = new THREE.WebGLRenderer();
// 设置渲染场景大小
renderer.setSize(window.innerWidth, window.innerHeight);
// 将渲染加到body
document.body.appendChild(renderer.domElement);// 创建物体
const geometry = new THREE.BoxGeometry(1, 1, 1, 2,2,3);
const material = new THREE.MeshBasicMaterial({color: '#30b2f4'});
const cube = new THREE.Mesh(geometry, material);// 场景中添加物体
scene.add(cube);// 设置相机位置
camera.position.z = 3;
camera.position.x = 2;
camera.position.y = 1;// 渲染
renderer.render(scene, camera);

浅加一个动画

window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画，并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。该方法需要传入一个回调函数作为参数，该回调函数会在浏览器下一次重绘之前执行

window.requestAnimationFrame(callback);

// 创建场景
const scene = new THREE.Scene();// 创建相机
const camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 1, 1000);// 渲染
const renderer = new THREE.WebGLRenderer();
// 设置渲染场景大小
renderer.setSize(window.innerWidth, window.innerHeight);
// 将渲染加到body
document.body.appendChild(renderer.domElement);// 创建物体
const geometry = new THREE.BoxGeometry(1, 1, 1, 2, 2, 3);
const material = new THREE.MeshBasicMaterial({ color: '#30b2f4' });
const cube = new THREE.Mesh(geometry, material);// 场景中添加物体
scene.add(cube);// 设置相机位置
camera.position.z = 3;
camera.position.x = 2;
camera.position.y = 1;// 添加动画效果
function animation() {window.requestAnimationFrame(animation);// cube.rotation.x += 0.01;// cube.rotation.y += 0.01;camera.position.z += 0.01camera.position.y += 0.01// 渲染renderer.render(scene, camera);
}animation()

添加曲线

参数解析

• points – Vector3点数组
• closed – 该曲线是否闭合，默认值为false。
• curveType – 曲线的类型，默认值为centripetal。
• tension – 曲线的张力，默认为0.5。

function CatmullRomCurve3( points, closed, curveType, tension ) {Curve.call( this );this.type = 'CatmullRomCurve3';this.points = points || [];this.closed = closed || false;this.curveType = curveType || 'centripetal';this.tension = tension || 0.5;}

function Vector3( x, y, z ) {this.x = x || 0;this.y = y || 0;this.z = z || 0;}

function BufferGeometry() {Object.defineProperty( this, 'id', { value: bufferGeometryId += 2 } );this.uuid = _Math.generateUUID();this.name = '';this.type = 'BufferGeometry';this.index = null;this.attributes = {};this.morphAttributes = {};this.groups = [];this.boundingBox = null;this.boundingSphere = null;this.drawRange = { start: 0, count: Infinity };}

function LineBasicMaterial( parameters ) {Material.call( this );this.type = 'LineBasicMaterial';this.color = new Color( 0xffffff );this.linewidth = 1;this.linecap = 'round';this.linejoin = 'round';this.lights = false;this.setValues( parameters );}

function Line( geometry, material, mode ) {if ( mode === 1 ) {console.warn( 'THREE.Line: parameter THREE.LinePieces no longer supported. Created THREE.LineSegments instead.' );return new LineSegments( geometry, material );}Object3D.call( this );this.type = 'Line';this.geometry = geometry !== undefined ? geometry : new BufferGeometry();this.material = material !== undefined ? material : new LineBasicMaterial( { color: Math.random() * 0xffffff } );}

//Create a closed wavey loop
const curve = new THREE.CatmullRomCurve3([new THREE.Vector3(-10, 0, 10),new THREE.Vector3(-5, 5, 5),new THREE.Vector3(0, 0, 0),new THREE.Vector3(5, -5, 5),new THREE.Vector3(10, 0, 10)
]);const points = curve.getPoints(50);
const geometryCurve = new THREE.BufferGeometry().setFromPoints(points);
const materialCurve = new THREE.LineBasicMaterial({ color: 0xff0000 });// Create the final object to add to the scene
const curveObject = new THREE.Line(geometryCurve, materialCurve);// 场景中添加物体
scene.add(curveObject);

添加灯光

function AmbientLight( color, intensity ) {Light.call( this, color, intensity );this.type = 'AmbientLight';this.castShadow = undefined;}

动画执行一段时间，移除物体

// 创建场景
const scene = new THREE.Scene();// 创建相机
const camera = new THREE.PerspectiveCamera(76, window.innerWidth / window.innerHeight, 1, 1000);// 渲染
const renderer = new THREE.WebGLRenderer();
// 设置渲染场景大小
renderer.setSize(window.innerWidth, window.innerHeight);
// 将渲染加到body
document.body.appendChild(renderer.domElement);// 创建物体
const geometry = new THREE.BoxGeometry(1, 1, 1, 2, 2, 3);
const material = new THREE.MeshBasicMaterial({ color: '#30b2f4' });
const cube = new THREE.Mesh(geometry, material);//Create a closed wavey loop
const curve = new THREE.CatmullRomCurve3([new THREE.Vector3(-10, 0, 10),new THREE.Vector3(-5, 5, 5),new THREE.Vector3(0, 0, 0),new THREE.Vector3(5, -5, 5),new THREE.Vector3(10, 0, 10)
]);const points = curve.getPoints(50);
const geometryCurve = new THREE.BufferGeometry().setFromPoints(points);
const materialCurve = new THREE.LineBasicMaterial({ color: 0xff0000 });// Create the final object to add to the scene
const curveObject = new THREE.Line(geometryCurve, materialCurve);// 添加灯光
const light = new THREE.AmbientLight('#52D59A'); // soft white light// 场景中添加物体
scene.add(light);scene.add(cube);
scene.add(curveObject);// 设置相机位置
camera.position.z = 3;
camera.position.x = 2;
camera.position.y = -2;let count = 0
// 添加动画效果
function animation() {if (count !== 110) {window.requestAnimationFrame(animation);renderer.render(scene, camera);}if (count >= 100) {scene.remove(cube)}// cube.rotation.x += 0.01;// cube.rotation.y += 0.01;camera.position.z += 0.01camera.position.y += 0.01count++;console.log('count', count);// 渲染
}animation()

function Object3D() {Object.defineProperty( this, 'id', { value: object3DId ++ } );this.uuid = _Math.generateUUID();this.name = '';this.type = 'Object3D';this.parent = null;this.children = [];this.up = Object3D.DefaultUp.clone();var position = new Vector3();var rotation = new Euler();var quaternion = new Quaternion();var scale = new Vector3( 1, 1, 1 );function onRotationChange() {quaternion.setFromEuler( rotation, false );}function onQuaternionChange() {rotation.setFromQuaternion( quaternion, undefined, false );}rotation.onChange( onRotationChange );quaternion.onChange( onQuaternionChange );Object.defineProperties( this, {position: {enumerable: true,value: position},rotation: {enumerable: true,value: rotation},quaternion: {enumerable: true,value: quaternion},scale: {enumerable: true,value: scale},modelViewMatrix: {value: new Matrix4()},normalMatrix: {value: new Matrix3()}} );this.matrix = new Matrix4();this.matrixWorld = new Matrix4();this.matrixAutoUpdate = Object3D.DefaultMatrixAutoUpdate;this.matrixWorldNeedsUpdate = false;this.layers = new Layers();this.visible = true;this.castShadow = false;this.receiveShadow = false;this.frustumCulled = true;this.renderOrder = 0;this.userData = {};}

修改渲染的背景颜色

// 渲染
const renderer = new THREE.WebGLRenderer();// 更改渲染背景色，默认为黑色
renderer.setClearColor('rgba(191, 115, 87, 0.95)', 1.0)

渲染3D文本

在官网可随意下载一个字体json文件放置本地使用
地址：https://github.com/mrdoob/three.js/tree/dev/examples/fonts

// 创建场景
const scene = new THREE.Scene();
const loader = new THREE.FontLoader();
loader.load('./gentilis_regular.json', function (font) {const geometryText = new THREE.TextGeometry('Hello three.js!', {font: font,size: 0.3,height: 0.1,// curveSegments: 12,//表示文本的）曲线上点的数量。默认值为12。// bevelEnabled: true,//是否开启斜角// bevelThickness: 10,//文本上斜角的深度，默认值为20。// bevelSize: 8,//斜角与原始文本轮廓之间的延伸距离。默认值为8。// bevelSegments: 5//斜角的分段数。默认值为3。});const m = new THREE.MeshBasicMaterial({color:'#ffffff'});const  mesh = new THREE.Mesh(geometryText,m);scene.add(mesh)
});

GitHub：https://github.com/mrdoob/three.js/blob/master/src/scenes/Scene.js