我正在寻找一种简单的算法来生成大量随机的、美观的颜色。所以没有疯狂的霓虹灯颜色，让人联想到粪便的颜色等等。
我已经找到了这个问题的解决方案，但它们依赖于替代调色板而不是RGB。 我宁愿直接使用RGB，而不是来回映射。这些其他解决方案也最多只能生成32种左右令人愉悦的随机颜色。
任何想法都很好。
当前回答
function fnGetRandomColour(iDarkLuma, iLightLuma)
{
for (var i=0;i<20;i++)
{
var sColour = ('ffffff' + Math.floor(Math.random() * 0xFFFFFF).toString(16)).substr(-6);
var rgb = parseInt(sColour, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff; // extract blue
var iLuma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709
if (iLuma > iDarkLuma && iLuma < iLightLuma) return sColour;
}
return sColour;
}
对于粉彩，传入更高亮度的暗/亮整数-即fnGetRandomColour(120,250)
学分:所有学分归 http://paulirish.com/2009/random-hex-color-code-snippets/ stackoverflow.com/questions/12043187/how-to-check-if-hex-color-is-too-black
其他回答
下面是c#中的一个快速而肮脏的颜色生成器(使用本文中描述的“RYB方法”)。这是JavaScript重写的。
Use:
List<Color> ColorPalette = ColorGenerator.Generate(30).ToList();
前两种颜色往往是白色和暗色的黑色。我经常这样跳过它们(使用Linq):
List<Color> ColorsPalette = ColorGenerator
.Generate(30)
.Skip(2) // skip white and black
.ToList();
实现:
public static class ColorGenerator
{
// RYB color space
private static class RYB
{
private static readonly double[] White = { 1, 1, 1 };
private static readonly double[] Red = { 1, 0, 0 };
private static readonly double[] Yellow = { 1, 1, 0 };
private static readonly double[] Blue = { 0.163, 0.373, 0.6 };
private static readonly double[] Violet = { 0.5, 0, 0.5 };
private static readonly double[] Green = { 0, 0.66, 0.2 };
private static readonly double[] Orange = { 1, 0.5, 0 };
private static readonly double[] Black = { 0.2, 0.094, 0.0 };
public static double[] ToRgb(double r, double y, double b)
{
var rgb = new double[3];
for (int i = 0; i < 3; i++)
{
rgb[i] = White[i] * (1.0 - r) * (1.0 - b) * (1.0 - y) +
Red[i] * r * (1.0 - b) * (1.0 - y) +
Blue[i] * (1.0 - r) * b * (1.0 - y) +
Violet[i] * r * b * (1.0 - y) +
Yellow[i] * (1.0 - r) * (1.0 - b) * y +
Orange[i] * r * (1.0 - b) * y +
Green[i] * (1.0 - r) * b * y +
Black[i] * r * b * y;
}
return rgb;
}
}
private class Points : IEnumerable<double[]>
{
private readonly int pointsCount;
private double[] picked;
private int pickedCount;
private readonly List<double[]> points = new List<double[]>();
public Points(int count)
{
pointsCount = count;
}
private void Generate()
{
points.Clear();
var numBase = (int)Math.Ceiling(Math.Pow(pointsCount, 1.0 / 3.0));
var ceil = (int)Math.Pow(numBase, 3.0);
for (int i = 0; i < ceil; i++)
{
points.Add(new[]
{
Math.Floor(i/(double)(numBase*numBase))/ (numBase - 1.0),
Math.Floor((i/(double)numBase) % numBase)/ (numBase - 1.0),
Math.Floor((double)(i % numBase))/ (numBase - 1.0),
});
}
}
private double Distance(double[] p1)
{
double distance = 0;
for (int i = 0; i < 3; i++)
{
distance += Math.Pow(p1[i] - picked[i], 2.0);
}
return distance;
}
private double[] Pick()
{
if (picked == null)
{
picked = points[0];
points.RemoveAt(0);
pickedCount = 1;
return picked;
}
var d1 = Distance(points[0]);
int i1 = 0, i2 = 0;
foreach (var point in points)
{
var d2 = Distance(point);
if (d1 < d2)
{
i1 = i2;
d1 = d2;
}
i2 += 1;
}
var pick = points[i1];
points.RemoveAt(i1);
for (int i = 0; i < 3; i++)
{
picked[i] = (pickedCount * picked[i] + pick[i]) / (pickedCount + 1.0);
}
pickedCount += 1;
return pick;
}
public IEnumerator<double[]> GetEnumerator()
{
Generate();
for (int i = 0; i < pointsCount; i++)
{
yield return Pick();
}
}
IEnumerator IEnumerable.GetEnumerator()
{
return GetEnumerator();
}
}
public static IEnumerable<Color> Generate(int numOfColors)
{
var points = new Points(numOfColors);
foreach (var point in points)
{
var rgb = RYB.ToRgb(point[0], point[1], point[2]);
yield return Color.FromArgb(
(int)Math.Floor(255 * rgb[0]),
(int)Math.Floor(255 * rgb[1]),
(int)Math.Floor(255 * rgb[2]));
}
}
}
在php中:
function pastelColors() {
$r = dechex(round(((float) rand() / (float) getrandmax()) * 127) + 127);
$g = dechex(round(((float) rand() / (float) getrandmax()) * 127) + 127);
$b = dechex(round(((float) rand() / (float) getrandmax()) * 127) + 127);
return "#" . $r . $g . $b;
}
来源:https://stackoverflow.com/a/12266311/2875783
在javascript中:
function pastelColors(){
var r = (Math.round(Math.random()* 127) + 127).toString(16);
var g = (Math.round(Math.random()* 127) + 127).toString(16);
var b = (Math.round(Math.random()* 127) + 127).toString(16);
return '#' + r + g + b;
}
在这里看到了这个想法:http://blog.functionalfun.net/2008/07/random-pastel-colour-generator.html
JavaScript改编的David Crow的原始答案，包括IE和Nodejs的特定代码。
generateRandomComplementaryColor = function(r, g, b){
//--- JavaScript code
var red = Math.floor((Math.random() * 256));
var green = Math.floor((Math.random() * 256));
var blue = Math.floor((Math.random() * 256));
//---
//--- Extra check for Internet Explorers, its Math.random is not random enough.
if(!/MSIE 9/i.test(navigator.userAgent) && !/MSIE 10/i.test(navigator.userAgent) && !/rv:11.0/i.test(navigator.userAgent)){
red = Math.floor((('0.' + window.crypto.getRandomValues(new Uint32Array(1))[0]) * 256));
green = Math.floor((('0.' + window.crypto.getRandomValues(new Uint32Array(1))[0]) * 256));
blue = Math.floor((('0.' + window.crypto.getRandomValues(new Uint32Array(1))[0]) * 256));
};
//---
//--- nodejs code
/*
crypto = Npm.require('crypto');
red = Math.floor((parseInt(crypto.randomBytes(8).toString('hex'), 16)) * 1.0e-19 * 256);
green = Math.floor((parseInt(crypto.randomBytes(8).toString('hex'), 16)) * 1.0e-19 * 256);
blue = Math.floor((parseInt(crypto.randomBytes(8).toString('hex'), 16)) * 1.0e-19 * 256);
*/
//---
red = (red + r)/2;
green = (green + g)/2;
blue = (blue + b)/2;
return 'rgb(' + Math.floor(red) + ', ' + Math.floor(green) + ', ' + Math.floor(blue) + ')';
}
运行函数使用:
generateRandomComplementaryColor(240, 240, 240);
你可以让它们在一定的亮度范围内。这样可以稍微控制“霓虹灯”颜色的数量。例如，如果“亮度”
brightness = sqrt(R^2+G^2+B^2)
在一定的高度范围内，它就会被洗掉，变成浅色。相反，如果它在某个下限内，它就会更暗。这将消除任何疯狂的、突出的颜色，如果你选择一个非常高或非常低的边界，它们都将非常接近白色或黑色。
