Canvas Konva框架实现钟表动画

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8" />
    <title>Document</title>
</head>
<body>
    <div id="box"></div>
</body>
<script src="../bower_components/konva/konva.min.js"></script>
<script type="text/javascript">
    var w = 800;
    var h = 600;
    var r = 200;
    var stage = new Konva.Stage({
        container: "box",
        width: w,
        height: h
    });
    var dialLayer = new Konva.Layer();
    stage.add(dialLayer);
    // 绘制表盘
    var dialCircle = new Konva.Circle({
        x: w/2,
        y: h/2,
        radius: r,
        stroke: "#000",
        strokeWidth: 10,
        fill: "#eee"
    });
    dialLayer.add(dialCircle);
    // 绘制刻度
    var bigDialScale = new DialScale({
        x: w/2,
        y: h/2,
        outerRadius: r,
        innerRadius: r-20,
        stroke: "#000",
        strokeWidth: 10,
        number: 12
    });
    dialLayer.add(bigDialScale);
    // 绘制小刻度
    var smallScale = new DialScale({
        x: w/2,
        y: h/2,
        outerRadius: r,
        innerRadius: r-10,
        stroke: "#000",
        strokeWidth: 2,
        number: 60
    });
    dialLayer.add(smallScale);
    // 绘制
    dialLayer.draw();

    // 创建指针层
    var handLayer = new Konva.Layer();
    stage.add(handLayer);
    var secondHand = new Konva.Line({
        x: w/2,
        y: h/2,
        points: [-20,0,180,0],
        stroke: "red",
        strokeWidth: "2",
        rotation: 0
    });
    handLayer.add(secondHand);
    // 绘制分针
    var minuteHand = new Konva.Line({
        x: w/2,
        y: h/2,
        points: [-20,0,150,0],
        stroke: "#000",
        strokeWidth: "5",
        rotation: 0
    });
    handLayer.add(minuteHand);
    // 时针
    var hourHand = new Konva.Line({
        x: w/2,
        y: h/2,
        points: [-20,0,120,0],
        stroke: "#000",
        strokeWidth: "8",
        rotation: 0
    });
    handLayer.add(hourHand);
    // 绘制圆心的小圆点
    var centerCircle = new Konva.Circle({
        x: w/2,
        y: h/2,
        radius: 10,
        fill: "#000"
    })
    handLayer.add(centerCircle);
    // 绘制指针层
    handLayer.draw();
    // 指针转动
    function run(){
        var date = new Date();
        // 秒针
        var seconds = date.getSeconds();
        secondHand.rotation(seconds/60 * 360 - 90);
        // 分针
        var minutes = date.getMinutes() + seconds/60;
        minuteHand.rotation(minutes/60 * 360 - 90);
        // 时针
        var hours = date.getHours() % 12 + minutes/60;
        hourHand.rotation(hours/12 * 360 - 90);
        handLayer.draw();
        setTimeout(run,1000);
    }
    run();
    // 生成表盘刻度的构造函数
    function DialScale(options){
        options = options || {};
        options.x = options.x || 0;
        options.y = options.y || 0;
        options.outerRadius = options.outerRadius || 0;
        options.innerRadius = options.innerRadius || 0;
        options.number = options.number || 12;
        options.strokeWidth = options.strokeWidth || 10;
        options.stroke = options.stroke || "#000";
        // 创建组
        var group = new Konva.Group({
            x: options.x,
            y: options.y
        });
        var angle = 0;
        var angleDiff = 360/options.number;
        for(var i=0; i<options.number; i++){
            var line = new Konva.Line({
                points: [
                    Math.cos(angle/180*Math.PI)*options.outerRadius,
                    Math.sin(angle/180*Math.PI)*options.outerRadius,
                    Math.cos(angle/180*Math.PI)*options.innerRadius,
                    Math.sin(angle/180*Math.PI)*options.innerRadius
                ],
                stroke: options.stroke,
                strokeWidth: options.strokeWidth
            });
            group.add(line);
            angle+=angleDiff;
        }
        return group;
    }
</script>
</html>
Canvas Konva框架实现钟表动画

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