js实现canvas爱心表白动画效果代码
代码语言:html
所属分类:动画
代码描述:js实现canvas爱心表白动画效果代码
下面为部分代码预览,完整代码请点击下载或在bfwstudio webide中打开
<!doctype html> <html> <head> <meta charset="utf-8"> <style> html, body { height: 100%; padding: 0; margin: 0; background: #000; } canvas { width: 100%; height: 100%; } </style> </head> <body> <canvas id="pinkboard"></canvas> <script> /* * Settings */ var settings = { particles: { length: 500, // maximum amount of particles duration: 2, // particle duration in sec velocity: 100, // particle velocity in pixels/sec effect: -0.75, // play with this for a nice effect size: 30, // particle size in pixels }, }; /* * RequestAnimationFrame polyfill by Erik M?ller */ (function(){var b=0;var c=["ms","moz","webkit","o"];for(var a=0;a<c.length&&!window.requestAnimationFrame;++a){window.requestAnimationFrame=window[c[a]+"RequestAnimationFrame"];window.cancelAnimationFrame=window[c[a]+"CancelAnimationFrame"]||window[c[a]+"CancelRequestAnimationFrame"]}if(!window.requestAnimationFrame){window.requestAnimationFrame=function(h,e){var d=new Date().getTime();var f=Math.max(0,16-(d-b));var g=window.setTimeout(function(){h(d+f)},f);b=d+f;return g}}if(!window.cancelAnimationFrame){window.cancelAnimationFrame=function(d){clearTimeout(d)}}}()); /* * Point class */ var Point = (function() { function Point(x, y) { this.x = (typeof x !== 'undefined') ? x : 0; this.y = (typeof y !== 'undefined') ? y : 0; } Point.prototype.clone = function() { return new Point(this.x, this.y); }; Point.prototype.length = function(length) { if (typeof length == 'undefined') return Math.sqrt(this.x * this.x + this.y * this.y); this.normalize(); this.x *= length; this.y *= length; return this; }; Point.prototype.normalize = function() { var length = this.length(); this.x /= length; this.y /= length; return this; }; return Point; })(); /* * Particle class */ var Particle = (function() { function Particle() { this.position = new Point(); this.velocity = new Point(); this.acceleration = new Point(); this.age = 0; } Particle.prototype.initialize = function(x, y, dx, dy) { this.position.x = x; this.position.y = y; this.velocity.x = dx; this.velocity.y = dy; this.acceleration.x = dx * settings.particles.effect; this.acceleration.y = dy * settings.particles.effect; this.age = 0; }; Particle.prototype.update = function(deltaTime) { this.position.x += this.velocity.x * deltaTime; this.position.y += this.velocity.y * deltaTime; this.velocity.x += this.acceleration.x * deltaTime; this.velocity.y += this.acceleration.y * deltaTime; this.age += deltaTime; }; Particle.prototype.draw = function(context, image) { function ease(t) { return (--t) * t * t + 1; } var size = image.width * ease(this.age / settings.particles.duration); context.globalAlpha = 1 - this.age / settings.particles.duration; context.drawImage(image, this.position.x - size / 2, this.position.y - size / 2, size, size); }; return Particle; })(); /* * ParticlePool class */ var ParticlePool = (function() { var particles, firstActive = 0, firstFree = 0, duration = settings.particles.duration; function ParticlePool(length) { // create and populate particle pool particles = new Array(length); for (var i = 0; i < particles.length; i++) particles[i] = new Particle(); } ParticlePool.prototype.add = function(x, y, dx, dy) { particles[firstFree].initialize(x, y, dx, dy); // handle circular queue firstFree++; if (firstFree == particles.length) firstFree = 0; if (firstActive == firstFree ) firstActive++; if (firstActive == particles.length) firstActive = 0; }; .........完整代码请登录后点击上方下载按钮下载查看
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