html 代码:
<canvas width="400" height="300" id="myLove"></canvas>
CSS 代码:
- <style>
- body {
- margin: 0;
- padding: 0;
- background: white;
- }
- #myCanvas {
- display: block;
- }
- </style>
javascript 代码:
- <script>
- window.requestAnimFrame = (function () {
- return window.requestAnimationFrame ||
- window.webkitRequestAnimationFrame ||
- window.mozRequestAnimationFrame ||
- window.oRequestAnimationFrame ||
- window.msRequestAnimationFrame ||
- function (callback) {
- window.setTimeout(callback, 1000 / 60);
- };
- })();
- var FX = {
- config : {
- background : 'rgba(250,250,250,0.2)',
- color : 'rgb(250,20,75)',
- highlight : 'rgb(250,20,20)'
- },
- dots : []
- };
- FX.canvas = document.getElementById('myLove');
- FX.ctx = FX.canvas.getContext('2d');
- Math.TO_RAD = Math.PI/180;
- Math.getDistance = function( x1, y1, x2, y2 ) {
- var xs = 0,
- ys = 0;
- xs = x1 - x2;
- ys = y1 - y2;
- xs = xs * xs;
- ys = ys * ys;
- return Math.sqrt( xs + ys );
- };
- Math.getDegree = function( x1, y1, x2, y2 ) {
- var dx = x2 - x1,
- dy = y2 - y1;
- return Math.atan2(dy,dx) / Math.TO_RAD;
- };
- var Dot = function( opts ) {
- this.color = opts.color;
- this.x = 0;
- this.y = 0;
- this.dest_x = (opts.dest_x - 75);
- this.dest_y = (opts.dest_y - 75);
- };
- Dot.prototype.update = function() {
- var d = this,
- dist_x = d.dest_x - d.x,
- dist_y = d.dest_y - d.y;
- d.x += dist_x * 0.05;
- d.y += dist_y * 0.05;
- FX.ctx.fillStyle = d.color;
- FX.ctx.fillRect( d.x-2, d.y-2, 4, 4 );
- };
- FX.setFullscreen = function() {
- FX.width = FX.canvas.width = window.innerWidth;
- FX.height = FX.canvas.height = window.innerHeight;
- };
- FX.handleMouseEvent = function(e, power) {
- var radius = 75,
- k = FX.dots.length,
- i=0,
- mx, my,
- dist, degree,
- d;
- if(e.offsetX) {
- mx = e.offsetX;
- my = e.offsetY;
- } else if(e.layerX) {
- mx = e.layerX;
- my = e.layerY;
- }
- mx -= FX.width/2;
- my -= FX.height/2;
- for( ;i<k;i=i+1 ) {
- d = FX.dots[i];
- dist = Math.getDistance( mx, my, d.x, d.y);
- if( dist < radius ) {
- degree = Math.getDegree( d.x, d.y, mx, my );
- d.x += (Math.cos( degree * Math.TO_RAD ) * ((radius-dist) * power));
- d.y += (Math.sin( degree * Math.TO_RAD ) * ((radius-dist) * power));
- d.color = FX.config.highlight;
- } else {
- d.color = FX.config.color;
- }
- }
- };
- FX.createHeart = function() {
- var coords = [[1,4],[1,5],[1,6],[1,7],[1,8],[2,3],[2,4],[2,5],[2,6],[2,7],[2,8],[2,9],[3,2],[3,3],[3,4],[3,5],[3,6],[3,7],[3,8],[3,9],[3,10],[4,2],[4,3],[4,4],[4,5],[4,6],[4,7],[4,8],[4,9],[4,10],[4,11],[5,2],[5,3],[5,4],[5,5],[5,6],[5,7],[5,8],[5,9],[5,10],[5,11],[6,2],[6,3],[6,4],[6,5],[6,6],[6,7],[6,8],[6,9],[6,10],[6,11],[6,12],[7,3],[7,4],[7,5],[7,6],[7,7],[7,8],[7,9],[7,10],[7,11],[7,12],[8,3],[8,4],[8,5],[8,6],[8,7],[8,8],[8,9],[8,10],[8,11],[8,12],[8,13],[9,2],[9,3],[9,4],[9,5],[9,6],[9,7],[9,8],[9,9],[9,10],[9,11],[9,12],[10,2],[10,3],[10,4],[10,5],[10,6],[10,7],[10,8],[10,9],[10,10],[10,11],[11,2],[11,3],[11,4],[11,5],[11,6],[11,7],[11,8],[11,9],[11,10],[11,11],[12,2],[12,3],[12,4],[12,5],[12,6],[12,7],[12,8],[12,9],[12,10],[13,3],[13,4],[13,5],[13,6],[13,7],[13,8],[13,9],[14,4],[14,5],[14,6],[14,7],[14,8]],
- k = coords.length,
- raster = 10,
- i = 0;
- for( ;i<k;i=i+1 ) {
- FX.dots.push( new Dot({
- dest_x : coords[i][0] * raster,
- dest_y : coords[i][1] * raster,
- color: FX.config.color
- }) );
- }
- };
- FX.loop = function() {
- var ctx = FX.ctx,
- k = FX.dots.length,
- i = 0;
- ctx.fillStyle = FX.config.background;
- ctx.fillRect(0,0, FX.width, FX.height );
- ctx.save();
- ctx.translate( FX.width/2, FX.height/2 );
- for( ;i<k;i=i+1 ) {
- FX.dots[i].update();
- }
- ctx.restore();
- requestAnimFrame( FX.loop );
- };
- window.addEventListener('resize', FX.setFullscreen );
- FX.canvas.addEventListener('mousemove', function(e) { FX.handleMouseEvent(e, -0.1); } );
- FX.canvas.addEventListener('mousedown', function(e) { FX.handleMouseEvent(e, 1); } );
- FX.setFullscreen();
- FX.createHeart();
- FX.loop();
- </script>
来源: http://www.jianshu.com/p/179a89141ceb