小猫抓毛线球特效详解编程语言

 效果图：

代码如下，复制即可使用：

 !DOCTYPE html 

 html 

 head 

 meta charset="UTF-8" 

 title Cat vs ball of wool /title 

 link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/meyer-reset/2.0/reset.min.css" 

 style 

 @import url(http://fonts.googleapis.com/css?family=Open+Sans:800); 

#world{ 

 position: absolute; 

 width:100%; 

 height: 100%; 

 background-color: #6ecccc; 

 overflow:hidden; 

#credits{ 

 position:absolute; 

 width:100%; 

 margin: auto; 

 bottom:0; 

 margin-bottom:20px; 

 font-family:Open Sans, sans-serif; 

 color:#328685; 

 font-size:0.7em; 

 text-transform: uppercase; 

 text-align : center; 

#credits a { 

 color:#328685; 

#credits a:hover { 

 color:#630d15; 

 /style 


 div id="world"/ 

 script src=http://cdnjs.cloudflare.com/ajax/libs/three.js/r70/three.min.js /script 

 script src=http://cdnjs.cloudflare.com/ajax/libs/gsap/1.16.1/TweenMax.min.js /script 

 script src=https://s3-us-west-2.amazonaws.com/s.cdpn.io/264161/OrbitControls.js /script 

 script src=https://s3-us-west-2.amazonaws.com/s.cdpn.io/264161/Cat.js /script 

 script 

//THREEJS RELATED VARIABLES 

var scene, 

 camera, fieldOfView, aspectRatio, nearPlane, farPlane, 

 gobalLight, shadowLight, backLight, 

 renderer, 

 container, 

 controls; 

//SCREEN MOUSE VARIABLES 

var HEIGHT, WIDTH, windowHalfX, windowHalfY, 

 mousePos = { x: 0, y: 0 }, 

 oldMousePos = {x:0, y:0}, 

 ballWallDepth = 28; 


 renderer = new THREE.WebGLRenderer({ alpha: true, antialias: true }); 

 renderer.setSize(WIDTH, HEIGHT); 

 renderer.shadowMapEnabled = true; 

 container = document.getElementById(world); 

 container.appendChild(renderer.domElement); 

 window.addEventListener(resize, handleWindowResize, false); 

 document.addEventListener(mousemove, handleMouseMove, false); 

 document.addEventListener(touchmove, handleTouchMove, false); 

 controls = new THREE.OrbitControls(camera, renderer.domElement); 

 controls.minPolarAngle = -Math.PI / 2; 

 controls.maxPolarAngle = Math.PI / 2; 

 controls.noZoom = true; 

 controls.noPan = true; 

 //*/ 


 event.preventDefault(); 

 mousePos = {x:event.touches[0].pageX, y:event.touches[0].pageY}; 

function createLights() { 

 globalLight = new THREE.HemisphereLight(0xffffff, 0xffffff, .5) 

 shadowLight = new THREE.DirectionalLight(0xffffff, .9); 

 shadowLight.position.set(200, 200, 200); 

 shadowLight.castShadow = true; 

 shadowLight.shadowDarkness = .2; 

 shadowLight.shadowMapWidth = shadowLight.shadowMapHeight = 2048; 

 backLight = new THREE.DirectionalLight(0xffffff, .4); 

 backLight.position.set(-100, 100, 100); 

 backLight.castShadow = true; 

 backLight.shadowDarkness = .1; 

 backLight.shadowMapWidth = shadowLight.shadowMapHeight = 2048; 

 scene.add(globalLight); 

 scene.add(shadowLight); 

 scene.add(backLight); 

function createFloor(){ 

 floor = new THREE.Mesh(new THREE.PlaneBufferGeometry(1000,1000), new THREE.MeshBasicMaterial({color: 0x6ecccc})); 

 floor.rotation.x = -Math.PI/2; 

 floor.position.y = 0; 

 floor.receiveShadow = true; 

 scene.add(floor); 

function createHero() { 

 hero = new Cat(); 

 scene.add(hero.threeGroup); 

function createBall() { 

 ball = new Ball(); 

 scene.add(ball.threeGroup); 

// BALL RELATED CODE 


 for (var i=0; i woolNodes; i++ ){ 

 var v = new THREE.Vector3(0, -i*woolSegLength, 0); 

 stringGeom.vertices.push(v); 

 var woolV = new WoolVert(); 

 woolV.x = woolV.oldx = v.x; 

 woolV.y = woolV.oldy = v.y; 

 woolV.z = 0; 

 woolV.fx = woolV.fy = 0; 

 woolV.isRootNode = (i==0); 

 woolV.vertex = v; 

 if (i 0) woolV.attach(this.verts[(i - 1)]); 

 this.verts.push(woolV); 

 this.string = new THREE.Line(stringGeom, stringMat); 

 // body 

 var bodyGeom = new THREE.SphereGeometry(this.ballRay, 5,4); 

 this.body = new THREE.Mesh(bodyGeom, redMat); 

 this.body.position.y = -woolSegLength*woolNodes; 

 var wireGeom = new THREE.TorusGeometry( this.ballRay, .5, 3, 10, Math.PI*2 ); 

 this.wire1 = new THREE.Mesh(wireGeom, redMat); 

 this.wire1.position.x = 1; 

 this.wire1.rotation.x = -Math.PI/4; 

 this.wire2 = this.wire1.clone(); 

 this.wire2.position.y = 1; 

 this.wire2.position.x = -1; 

 this.wire1.rotation.x = -Math.PI/4 + .5; 

 this.wire1.rotation.y = -Math.PI/6; 

 this.wire3 = this.wire1.clone(); 

 this.wire3.rotation.x = -Math.PI/2 + .3; 

 this.wire4 = this.wire1.clone(); 

 this.wire4.position.x = -1; 

 this.wire4.rotation.x = -Math.PI/2 + .7; 

 this.wire5 = this.wire1.clone(); 

 this.wire5.position.x = 2; 

 this.wire5.rotation.x = -Math.PI/2 + 1; 

 this.wire6 = this.wire1.clone(); 

 this.wire6.position.x = 2; 

 this.wire6.position.z = 1; 

 this.wire6.rotation.x = 1; 

 this.wire7 = this.wire1.clone(); 

 this.wire7.position.x = 1.5; 

 this.wire7.rotation.x = 1.1; 

 this.wire8 = this.wire1.clone(); 

 this.wire8.position.x = 1; 

 this.wire8.rotation.x = 1.3; 

 this.wire9 = this.wire1.clone(); 

 this.wire9.scale.set(1.2,1.1,1.1); 

 this.wire9.rotation.z = Math.PI/2; 

 this.wire9.rotation.y = Math.PI/2; 

 this.wire9.position.y = 1; 

 this.body.add(this.wire1); 

 this.body.add(this.wire2); 

 this.body.add(this.wire3); 

 this.body.add(this.wire4); 

 this.body.add(this.wire5); 

 this.body.add(this.wire6); 

 this.body.add(this.wire7); 

 this.body.add(this.wire8); 

 this.body.add(this.wire9); 

 this.threeGroup.add(this.string); 

 this.threeGroup.add(this.body); 

 this.threeGroup.traverse( function ( object ) { 

 if ( object instanceof THREE.Mesh ) { 

 object.castShadow = true; 

 object.receiveShadow = true; 

 }}); 

The next part of the code is largely inspired by this codepen : 

thanks to dissimulate for his great work 

Copyright (c) 2013 dissimulate at Codepen 

Permission is hereby granted, free of charge, to any person obtaining a copy 

of this software and associated documentation files (the "Software"), to deal 

in the Software without restriction, including without limitation the rights 

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 

copies of the Software, and to permit persons to whom the Software is 

furnished to do so, subject to the following conditions: 

The above copyright notice and this permission notice shall be included in 

all copies or substantial portions of the Software. 

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 

THE SOFTWARE. 


 nx = this.x + ((this.x - this.oldx)*.9) + this.fx; 

 ny = this.y + ((this.y - this.oldy)*.9) + this.fy; 

 this.oldx = this.x; 

 this.oldy = this.y; 

 this.x = nx; 

 this.y = ny; 

 this.vertex.x = this.x; 

 this.vertex.y = this.y; 

 this.vertex.z = this.z; 

 this.fy = this.fx = 0 

WoolVert.prototype.attach = function(point) { 

 this.constraints.push(new Constraint(this, point)); 

WoolVert.prototype.add_force = function(x, y) { 

 this.fx += x; 

 this.fy += y; 

Constraint = function(p1, p2) { 

 this.p1 = p1; 

 this.p2 = p2; 

 this.length = woolSegLength; 

Ball.prototype.update = function(posX, posY, posZ){ 

 var i = accuracy; 

 while (i--) { 

 var nodesCount = woolNodes; 

 while (nodesCount--) { 

 var v = this.verts[nodesCount]; 

 if (v.isRootNode) { 

 v.x = posX; 

 v.y = posY; 

 v.z = posZ; 

 else { 

 var constraintsCount = v.constraints.length; 

 while (constraintsCount--) { 

 var c = v.constraints[constraintsCount]; 

 var diff_x = c.p1.x - c.p2.x, 

 diff_y = c.p1.y - c.p2.y, 

 dist = Math.sqrt(diff_x * diff_x + diff_y * diff_y), 

 diff = (c.length - dist) / dist; 

 var px = diff_x * diff * .5; 

 var py = diff_y * diff * .5; 

 c.p1.x += px; 

 c.p1.y += py; 

 c.p2.x -= px; 

 c.p2.y -= py; 

 c.p1.z = c.p2.z = posZ; 

 if (nodesCount == woolNodes-1){ 

 this.body.position.x = this.verts[nodesCount].x; 

 this.body.position.y = this.verts[nodesCount].y; 

 this.body.position.z = this.verts[nodesCount].z; 

 this.body.rotation.z += (v.y = this.ballRay)? (v.oldx-v.x)/10 : Math.min(Math.max( diff_x/2, -.1 ), .1); 

 if (v.y this.ballRay) { 

 v.y = this.ballRay; 

 nodesCount = woolNodes; 

 while (nodesCount--) this.verts[nodesCount].update(); 

 this.string.geometry.verticesNeedUpdate = true; 


Ball.prototype.receivePower = function(tp){ 

 this.verts[woolNodes-1].add_force(tp.x, tp.y); 

// Enf of the code inspired by dissmulate 


 ( mousePos.x / window.innerWidth ) * 2 - 1, 

 - ( mousePos.y / window.innerHeight ) * 2 + 1, 

 0.1 ); 

 vector.unproject( camera ); 

 var dir = vector.sub( camera.position ).normalize(); 

 var distance = (ballWallDepth - camera.position.z) / dir.z; 

 var pos = camera.position.clone().add( dir.multiplyScalar( distance ) ); 

 return pos; 

function render(){ 

 if (controls) controls.update(); 

 renderer.render(scene, camera); 

window.addEventListener(load, init, false); 

function init(event){ 

 initScreenAnd3D(); 

 createLights(); 

 createFloor() 

 createHero(); 

 createBall(); 

 loop(); 

 /script 

 /body 

 /html 

 如有错误，欢迎联系我改正，非常感谢！！！

原创文章，作者：ItWorker，如若转载，请注明出处：https://blog.ytso.com/12328.html