Question

我一直致力于这个涉及纺车的代码笔项目。我想知道如何检测指针指向哪个段。下面是javascript。我想我必须将360度除以我所拥有的段数。提前谢谢，抱歉我的英语不好。我来自阿根廷。

http://codepen.io/AndreCortellini/pen/vERwmL

//set default degree (360*5)
var degree = 1800;
//number of clicks = 0
var clicks = 0;

$(document).ready(function(){

    /*WHEEL SPIN FUNCTION*/
    $('#spin').click(function(){

        //add 1 every click
        clicks ++;

        /*multiply the degree by number of clicks
      generate random number between 1 - 360, 
    then add to the new degree*/
        var newDegree = degree*clicks;
        var extraDegree = Math.floor(Math.random() * (360 - 1 + 1)) + 1;
        totalDegree = newDegree+extraDegree;

        /*let's make the spin btn to tilt every
        time the edge of the section hits 
        the indicator*/
        $('#wheel .sec').each(function(){
            var t = $(this);
            var noY = 0;

            var c = 0;
            var n = 700;    
            var interval = setInterval(function () {
                c++;                
                if (c === n) { 
                    clearInterval(interval);                
                }   

                var aoY = t.offset().top;
                $("#txt").html(aoY);
                console.log(aoY);

                /*23.7 is the minumum offset number that 
                each section can get, in a 30 angle degree.
                So, if the offset reaches 23.7, then we know
                that it has a 30 degree angle and therefore, 
                exactly aligned with the spin btn*/
                if(aoY < 23.89){
                    console.log('<<<<<<<<');
                    $('#spin').addClass('spin');
                    setTimeout(function () { 
                        $('#spin').removeClass('spin');
                    }, 100);    
                }
            }, 10);

            $('#inner-wheel').css({
                'transform' : 'rotate(' + totalDegree + 'deg)'          
            });

            noY = t.offset().top;

        });
    });



});//DOCUMENT READY

Answer 1

我们需要先找[0..360]度的学位，所以我们计算(totalDegree % 360)。
然后我们看到[31..90]代表橙色，[91..150]代表黄色，[151..210]代表深蓝色等等...... 换句话说，

[31..90]   => 1, orange  
[91..150]  => 2, yellow  
[151..210] => 3, dark blue  
[211..270] => 4, blue  
[271..330] => 5, cyan  
[331..30]  => 0, red

这让我想起了划分和舍入：(deg / 60)并将其四舍五入为整数。例如：

31 / 60 = 0.516 ~ 1  
32 / 60 = 0.533 ~ 1  
...  
45 / 60 = 0.750 ~ 1  
...  
88 / 60 = 1.466 ~ 1  
89 / 60 = 1.483 ~ 1  
90 / 60 = 1.500 ~ 2  
91 / 60 = 1.516 ~ 2  
...

所以，正如你所看到的，函数roundToInteger((deg / 60))完全符合我们的目的！
就JavaScript而言：

var sector = ((totalDegree % 360) / 60).toFixed(0);
$("#txt").html(sector);

请参阅http://codepen.io/mr_nameless/pen/yVmRxW

纺车轮段检测系统

1 个答案: