给定这个函数,我想用随机颜色生成器替换颜色。

document.overlay = GPolyline.fromEncoded({
    color: "#0000FF",
    weight: 10,
    points: encoded_points,
    zoomFactor: 32,
    levels: encoded_levels,
    numLevels: 4
});

我该怎么做呢?


当前回答

function randomColor(format = 'hex') {
    const rnd = Math.random().toString(16).slice(-6);
    if (format === 'hex') {
        return '#' + rnd;
    }
    if (format === 'rgb') {
        const [r, g, b] = rnd.match(/.{2}/g).map(c=>parseInt(c, 16));
        return `rgb(${r}, ${g}, ${b})`;
    }
}

其他回答

有多种方法来创建随机十六进制颜色代码在博客文章中随机十六进制颜色代码生成器在JavaScript。当随机值小于0×100000时,你需要用0填充,所以下面是正确的版本:

var randomColor = "#000000".replace(/0/g,function(){return (~~(Math.random()*16)).toString(16);});

这将用一个随机的十六进制数字替换六个0中的每一个,因此它一定会得到一个完整的六位数有效颜色值。

另一个随机颜色生成器:

var randomColor;
randomColor = Math.random() * 0x1000000; // 0 < randomColor < 0x1000000 (randomColor is a float)
randomColor = Math.floor(randomColor); // 0 < randomColor <= 0xFFFFFF (randomColor is an integer)
randomColor = randomColor.toString(16); // hex representation randomColor
randomColor = ("000000" + randomColor).slice(-6); // leading zeros added
randomColor = "#" + randomColor; // # added

我已经生成了100种不同对比度的不同颜色,你可以根据需要增加数值:

Feedle举例:http://jsfiddle.net/zFbfE/29/ -

// CHANGE THE INITIAL SEED HERE
Math.seed = 23;

/**
 * Math.seededRandom()
 *
 */
Math.seededRandom = function(max, min) {
    max = max || 1;
    min = min || 0;

    Math.seed = (Math.seed * 9301 + 49297) % 233280;
    var rnd = Math.seed / 233280.0;

    return min + rnd * (max - min);
}

var c, r = 0,
    l = 100000,
    t,
    random = [],
    seededRandom = [];

for(var i=0; i<100; i++)
{
    random[i] = 0;
    seededRandom[i] = 0;
}

// Do some loops withouth benchmarking
// to have a "fair" comparison
/*for (c = 0; c < l; ++c) {
    r = 5+5;
}*/


// benchmark Math.random()
t = new Date().getTime();
s = '';


// benchmark Math.seededRandom()
t = new Date().getTime();
while(l--){
    r = Math.seededRandom();
    seededRandom[(r*100)|0] += 1;
}

var inc = 0;
for(c=0; c<seededRandom.length; c++) {
    //var inc=15;
    for(var i=0; i<seededRandom.length; i++)
    {
        if(i!==c) {
            if(seededRandom[c] == seededRandom[i]) {
            seededRandom[c] += inc;
            inc = inc + 10;
              //    console.log(seededRandom[c]);
            }
        }
    }
    inc = inc > 255 ? 0 : inc;
}

var a=[], b=[], d=[], inc=0, dec=255;
for(c=0; c<seededRandom.length; c++) {
    a[c] = (seededRandom[c] % 100) + inc;
    b[c] = dec - Math.floor(seededRandom[c]/100);
    if(b[c] < 0)
        b[c] = b[c]* - 1;
    if(a[c] > 255)
        a[c] -= 255;
    d[c] = Math.floor(b[c]/2);
    inc += 5;
    dec -= 5;
}


var app = angular.module("myAppp", []).controller('myCtrl',function($scope, $http) {
$scope.id = [];
for(var i=0; i<seededRandom.length; i++)
    $scope.id.push(i);

// Generate random number
$scope.Icon = [];$scope.Icon2 = [], $scope.Icon3 = [];

var ran = 0, inc = 5, dec = 255;
for(var i=0;i<seededRandom.length;i++)
{
    $scope.Icon.push(a[i]%100);
    $scope.Icon2.push(b[i]%100);
    $scope.Icon3.push(d[i]%100);
    console.log(a[i] + "|" + b[i] + "|" + d[i]);
}

});

它对我有用,我想它对你也会有帮助。

这个例子中最好的一点是,它将生成100个随机颜色,并且每个页面加载的颜色都是相同的。

Array.prototype.reduce使它非常简洁。

["r", "g", "b"].reduce(function(res) {
    return res + ("0" + ~~(Math.random()*256).toString(16)).slice(-2)
}, "#")

它需要一个旧浏览器的垫片。

'#'+Math.random().toString(16).slice(-3) // three-numbers format aka #f3c
'#'+Math.random().toString(16).slice(-6) // six-number format aka #abc123