javascript实现很浪漫的气泡冒出特效代码,在博客中添加浪漫元素,这不失为一种好的方式,希望大家灵活运用,分享给大家供大家参考,具体如下
<canvas id="canvas" width="1080" height ="2337"></canvas>
HTML里只需要一个CANVAS元素,Javascript里操作canvas
圆形背景色可以是随机,那就是各种色彩了! 利用计时器控制y--
<canvas id="canvas"></canvas>
<script>
var canvas=document.getElementById("canvas");
var context=canvas.getContext("2d");
canvas.width=window.innerWidth;
canvas.height=window.innerHeight;
function Circle(){
this.x=Math.random()*canvas.width;
this.y=canvas.height;
this.r=Math.random()*10;
//绘制圆形
this.paint=function(){
context.beginPath();
context.arc(this.x,this.y,this.r,0,Math.PI*2);
context.fillStyle="white";
context.globalAlpha = 0.5;
context.fill();
}
//控制圆形移动
this.step=function(){
this.y--;
}
}
var circles=[];
function createCircles(){
var circle=new Circle();
circles[circles.length]=circle;
}
function paintCircles(){
for(var i=0;i<circles.length;i++){
circles[i].paint();
}
}
function stepCircles(){
for(var i=0;i<circles.length;i++){
circles[i].step();
}
}
var myimg=new Image();
myimg.src="图片地址";
var timer="";
setInterval(function(){
context.drawImage(myimg,0,0);
timer++;
if(timer%20==0){
createCircles();
}
paintCircles();
stepCircles();
},10);
</script>