使用canvas实现数字时钟效果

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<canvas id="canvas"></canvas>


<script>
    (function(){

        var digit=
            [
                [
                    [0,0,1,1,1,0,0],
                    [0,1,1,0,1,1,0],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,0,1,1,0],
                    [0,0,1,1,1,0,0]
                ],//0
                [
                    [0,0,0,1,1,0,0],
                    [0,1,1,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [1,1,1,1,1,1,1]
                ],//1
                [
                    [0,1,1,1,1,1,0],
                    [1,1,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,0,0],
                    [0,0,1,1,0,0,0],
                    [0,1,1,0,0,0,0],
                    [1,1,0,0,0,0,0],
                    [1,1,0,0,0,1,1],
                    [1,1,1,1,1,1,1]
                ],//2
                [
                    [1,1,1,1,1,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,0,0,1,1,0],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,1,1,0]
                ],//3
                [
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,1,0],
                    [0,0,1,1,1,1,0],
                    [0,1,1,0,1,1,0],
                    [1,1,0,0,1,1,0],
                    [1,1,1,1,1,1,1],
                    [0,0,0,0,1,1,0],
                    [0,0,0,0,1,1,0],
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,1,1]
                ],//4
                [
                    [1,1,1,1,1,1,1],
                    [1,1,0,0,0,0,0],
                    [1,1,0,0,0,0,0],
                    [1,1,1,1,1,1,0],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,1,1,0]
                ],//5
                [
                    [0,0,0,0,1,1,0],
                    [0,0,1,1,0,0,0],
                    [0,1,1,0,0,0,0],
                    [1,1,0,0,0,0,0],
                    [1,1,0,1,1,1,0],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,1,1,0]
                ],//6
                [
                    [1,1,1,1,1,1,1],
                    [1,1,0,0,0,1,1],
                    [0,0,0,0,1,1,0],
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,0,0],
                    [0,0,0,1,1,0,0],
                    [0,0,1,1,0,0,0],
                    [0,0,1,1,0,0,0],
                    [0,0,1,1,0,0,0],
                    [0,0,1,1,0,0,0]
                ],//7
                [
                    [0,1,1,1,1,1,0],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,1,1,0],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,1,1,0]
                ],//8
                [
                    [0,1,1,1,1,1,0],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [1,1,0,0,0,1,1],
                    [0,1,1,1,0,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,0,1,1],
                    [0,0,0,0,1,1,0],
                    [0,0,0,1,1,0,0],
                    [0,1,1,0,0,0,0]
                ],//9
                [
                    [0,0,0,0,0,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,0,0,0,0,0],
                    [0,0,0,0,0,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,1,1,1,0,0],
                    [0,0,0,0,0,0,0]
                ]//:
            ];

        var canvas = document.getElementById(canvas);
        //声明canvas的宽高
        var H = 30,W = 300;
        canvas.height = H;
        canvas.width = W;
        if(canvas.getContext){
            var cxt = canvas.getContext(2d);
        }
        cxt.fillStyle = #f00;
        cxt.fillRect(10,10,50,50);
        cxt.strokeStyle = "#0f0"


        //存储时间数据
        var data = [];
        //存储运动的小球
        var balls = [];
        //设置粒子半径
        var R = canvas.height/20-1;
        (function(){
            var temp = /(\d)(\d):(\d)(\d):(\d)(\d)/.exec(new Date());
            //存储时间数字,由十位小时、个位小时、冒号、十位分钟、个位分钟、冒号、十位秒钟、个位秒钟这7个数字组成
            data.push(temp[1],temp[2],10,temp[3],temp[4],10,temp[5],temp[6]);
        })();

        /*生成点阵数字*/
        function renderDigit(index,num){
            for(var i = 0; i < digit[num].length; i++){
                for(var j = 0; j < digit[num][i].length; j++){
                    if(digit[num][i][j] == 1){
                        cxt.beginPath();
                        cxt.arc(14*(R+2)*index + j*2*(R+1)+(R+1),i*2*(R+1)+(R+1),R,0,2*Math.PI);
                        cxt.closePath();
                        cxt.fill();
                    }
                }
            }
        }

        /*更新时钟*/
        function updateDigitTime(){
            var changeNumArray = [];
            var temp = /(\d)(\d):(\d)(\d):(\d)(\d)/.exec(new Date());
            var NewData = [];
            NewData.push(temp[1],temp[2],10,temp[3],temp[4],10,temp[5],temp[6]);
            for(var i = data.length-1; i >=0 ; i--){
                //时间发生变化
                if(NewData[i] !== data[i]){
                    //将变化的数字值和在data数组中的索引存储在changeNumArray数组中
                    changeNumArray.push(i+_+(Number(data[i])+1)%10);
                }
            }
            //增加小球
            for(var i = 0; i< changeNumArray.length; i++){
                addBalls.apply(this,changeNumArray[i].split(_));
            }
            data = NewData.concat();
        }

        /*更新小球状态*/
        function updateBalls(){
            for(var i = 0; i < balls.length; i++){
                balls[i].stepY += balls[i].disY;
                balls[i].x += balls[i].stepX;
                balls[i].y += balls[i].stepY;
                if(balls[i].x > W + R || balls[i].y > H + R){
                    balls.splice(i,1);
                    i--;
                }
            }
        }

        /*增加要运动的小球*/
        function addBalls(index,num){
            var numArray = [1,2,3];
            var colorArray =  ["#3BE","#09C","#A6C","#93C","#9C0","#690","#FB3","#F80","#F44","#C00"];
            for(var i = 0; i < digit[num].length; i++){
                for(var j = 0; j < digit[num][i].length; j++){
                    if(digit[num][i][j] == 1){
                        var ball = {
                            x:14*(R+2)*index + j*2*(R+1)+(R+1),
                            y:i*2*(R+1)+(R+1),
                            stepX:Math.floor(Math.random() * 4 -2),
                            stepY:-2*numArray[Math.floor(Math.random()*numArray.length)],
                            color:colorArray[Math.floor(Math.random()*colorArray.length)],
                            disY:1
                        };
                        balls.push(ball);
                    }
                }
            }
        }

        /*渲染*/
        function render(){
            //重置画布宽度,达到清空画布的效果
            canvas.height = 100;
            //渲染时钟
            for(var i = 0; i < data.length; i++){
                renderDigit(i,data[i]);
            }
            //渲染小球
            for(var i = 0; i < balls.length; i++){
                cxt.beginPath();
                cxt.arc(balls[i].x,balls[i].y,R,0,2*Math.PI);
                cxt.fillStyle = balls[i].color;
                cxt.closePath();
                cxt.fill();
            }
        }

        clearInterval(oTimer);
        var oTimer = setInterval(function(){
            //更新时钟
            updateDigitTime();
            //更新小球状态
            updateBalls();
            //渲染
            render();
        },50);

    })();

</script>

 

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