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?
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
这个函数在两个方面超越了其他答案:
它试图生成尽可能不同的颜色 20种颜色中哪一种与欧几里得距离最远 其他的都在HSV锥内。
它允许你限制色调, 饱和度,或值范围,但它仍然试图选择颜色作为 在这个范围内尽可能的不同。
它不是超级高效,但对于合理的值(谁甚至可以轻松地区分100种颜色?)够快了。
请参阅 JSFiddle
/**
* Generates a random palette of HSV colors. Attempts to pick colors
* that are as distinct as possible within the desired HSV range.
*
* @param {number} [options.numColors=10] - the number of colors to generate
* @param {number[]} [options.hRange=[0,1]] - the maximum range for generated hue
* @param {number[]} [options.sRange=[0,1]] - the maximum range for generated saturation
* @param {number[]} [options.vRange=[0,1]] - the maximum range for generated value
* @param {number[][]}[options.exclude=[[0,0,0],[0,0,1]]] - colors to exclude
*
* @returns {number[][]} an array of HSV colors (each HSV color
* is a [hue, saturation, value] array)
*/
function randomHSVPalette(options) {
function random(min, max) {
return min + Math.random() * (max - min);
}
function HSVtoXYZ(hsv) {
var h = hsv[0];
var s = hsv[1];
var v = hsv[2];
var angle = h * Math.PI * 2;
return [Math.sin(angle) * s * v,
Math.cos(angle) * s * v,
v];
}
function distSq(a, b) {
var dx = a[0] - b[0];
var dy = a[1] - b[1];
var dz = a[2] - b[2];
return dx * dx + dy * dy + dz * dz;
}
if (!options) {
options = {};
}
var numColors = options.numColors || 10;
var hRange = options.hRange || [0, 1];
var sRange = options.sRange || [0, 1];
var vRange = options.vRange || [0, 1];
var exclude = options.exclude || [[0, 0, 0], [0, 0, 1]];
var points = exclude.map(HSVtoXYZ);
var result = [];
while (result.length < numColors) {
var bestHSV;
var bestXYZ;
var bestDist = 0;
for (var i = 0; i < 20; i++) {
var hsv = [random(hRange[0], hRange[1]), random(sRange[0], sRange[1]), random(vRange[0], vRange[1])];
var xyz = HSVtoXYZ(hsv);
var minDist = 10;
points.forEach(function(point) {
minDist = Math.min(minDist, distSq(xyz, point));
});
if (minDist > bestDist) {
bestHSV = hsv;
bestXYZ = xyz;
bestDist = minDist;
}
}
points.push(bestXYZ);
result.push(bestHSV);
}
return result;
}
function HSVtoRGB(hsv) {
var h = hsv[0];
var s = hsv[1];
var v = hsv[2];
var i = ~~(h * 6);
var f = h * 6 - i;
var p = v * (1 - s);
var q = v * (1 - f * s);
var t = v * (1 - (1 - f) * s);
v = ~~(255 * v);
p = ~~(255 * p);
q = ~~(255 * q);
t = ~~(255 * t);
switch (i % 6) {
case 0: return [v, t, p];
case 1: return [q, v, p];
case 2: return [p, v, t];
case 3: return [p, q, v];
case 4: return [t, p, v];
case 5: return [v, p, q];
}
}
function RGBtoCSS(rgb) {
var r = rgb[0];
var g = rgb[1];
var b = rgb[2];
var rgb = (r << 16) + (g << 8) + b;
return '#' + ('000000' + rgb.toString(16)).slice(-6);
}
其他回答
我喜欢这个:'#' + (Math.random().toString(16) + "000000").substring(2,8)
下面是@Anatoliy提供的解决方案。
我只需要生成浅色(作为背景),所以我使用了三个字母(#AAA)格式:
function get_random_color() {
var letters = 'ABCDE'.split('');
var color = '#';
for (var i=0; i<3; i++ ) {
color += letters[Math.floor(Math.random() * letters.length)];
}
return color;
}
'#'+Math.random().toString(16).slice(-3) // three-numbers format aka #f3c
'#'+Math.random().toString(16).slice(-6) // six-number format aka #abc123
有很多方法可以做到这一点。以下是我做的一些:
简短的一行代码,保证有效的颜色
'#'+(Math.random().toString(16)+'00000').slice(2,8)
生成6个随机十六进制数字(0-F)
function randColor() {
for (var i=0, col=''; i<6; i++) {
col += (Math.random()*16|0).toString(16);
}
return '#'+col;
}
// ES6 one-liner version
[..."000000"].map(()=>Math.random().toString(16)[2]).join("")
生成单独的HEX组件(00-FF)
function randColor2() {
var r = ('0'+(Math.random()*256|0).toString(16)).slice(-2),
g = ('0'+(Math.random()*256|0).toString(16)).slice(-2),
b = ('0'+(Math.random()*256|0).toString(16)).slice(-2);
return '#' +r+g+b;
}
过度设计的十六进制字符串(XORs 3输出一起形成颜色)
function randColor3() {
var str = Math.random().toString(16) + Math.random().toString(16),
sg = str.replace(/0./g,'').match(/.{1,6}/g),
col = parseInt(sg[0], 16) ^
parseInt(sg[1], 16) ^
parseInt(sg[2], 16);
return '#' + ("000000" + col.toString(16)).slice(-6);
}
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。