js Canvas绘制圆形时钟效果
程序员文章站
2023-12-06 11:42:52
本文实例为大家分享了js canvas圆形时钟的具体实现代码，供大家参考，具体内容如下
...
本文实例为大家分享了js canvas圆形时钟的具体实现代码，供大家参考，具体内容如下
<!doctype html>
<html>
<head>
<meta charset="utf-8" />
<title>canvas clock</title>
<style type="text/css">
div{
text-align: center;
margin-top: 250px;
}
#clock{
border: 1px solid #ccc;
}
</style>
</head>
<body>
<div>
<canvas id="clock" height="200px" width="200px"></canvas>
</div>
<script type="text/javascript" src="js/clock.js"></script>
</body>
</html>
js
var dom=document.getelementbyid('clock');
var cxt=dom.getcontext("2d");
var width=cxt.canvas.width;
var height=cxt.canvas.height;
var r=width/2;
function drawbackground(){
cxt.save();
cxt.translate(r,r);
cxt.beginpath();
cxt.linewidth=10;
cxt.arc(0,0,r-5,0,2*math.pi,false);
cxt.stroke();
cxt.font="18px arial";
cxt.textalign='center'
cxt.textbaseline='middle'
var hournums=[3,4,5,6,7,8,9,10,11,12,1,2];
hournums.foreach(function(number,i){
var rad=2*math.pi/12*i;
var x=math.cos(rad)*(r-30);
var y=math.sin(rad)*(r-30);
cxt.filltext(number,x,y);
});
for(var i=0;i<60;i++){
var rad=2*math.pi/60*i;
var x=math.cos(rad)*(r-18);
var y=math.sin(rad)*(r-18);
cxt.beginpath();
if(i % 5===0){
cxt.fillstyle="#000"
cxt.arc(x,y,2,0,2*math.pi,false);
}
else{
cxt.fillstyle="#ccc"
cxt.arc(x,y,2,0,2*math.pi,false);
}
cxt.fill();
}
}
function drawhour(hour,minute){
cxt.save();
cxt.beginpath();
var rad=2*math.pi/12*hour;
var mrad=2*math.pi/12/60*minute
cxt.rotate(rad+mrad);
cxt.linewidth=6;
cxt.linecap='round'
cxt.moveto(0,10);
cxt.lineto(0,-r/2);
cxt.stroke();
cxt.restore();
}
function drawminute(minute){
cxt.save();
cxt.beginpath();
var rad=2*math.pi/60*minute;
cxt.rotate(rad);
cxt.linewidth=3;
cxt.linecap='round'
cxt.moveto(0,10);
cxt.lineto(0,-r+30);
cxt.stroke();
cxt.restore();
}
function drawsecond(second){
cxt.save();
cxt.beginpath();
cxt.fillstyle='#c14543'
var rad=2*math.pi/60*second;
cxt.rotate(rad);
cxt.moveto(-2,20);
cxt.lineto(2,20);
cxt.lineto(1,-r+18);
cxt.lineto(-1,-r+18);
cxt.fill();
cxt.restore();
}
function drawdot(){
cxt.beginpath();
cxt.fillstyle='#fff'
cxt.arc(0,0,3,0,2*math.pi,false);
cxt.fill();
}
function draw(){
cxt.clearrect(0,0,width,height);
var now=new date();
var hour=now.gethours();
var minute=now.getminutes();
var second=now.getseconds();
drawbackground();
drawhour(hour,minute);
drawminute(minute);
drawsecond(second);
drawdot();
cxt.restore();
}
draw();
setinterval(draw,1000);
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。