定义
        HSL即色相、饱和度、亮度（英语：Hue, Saturation, Lightness）。
        色相（H）是色彩的基本属性，就是平常所说的颜色名称，如红色、黄色等。可以说和光谱对应。取值为0-360度。
        饱和度（S）是指色彩的纯度，越高色彩越纯，低则逐渐变灰，取0-100%的数值。
        明度（V），亮度（L），取0-100%。
        如图所示，圆柱从低向上，表示亮度，由中轴向外表示饱和度，水平截面的圆周角表示色相。

        如果用圆锥表示则为双圆锥：这种表示放法相比较圆柱更加直观，最低端的只用一个点表示黑色，如果用圆柱，用了一面表示黑色，无太大意义。从圆锥上可以看出，亮度的调节会影响颜色的丰富程度。

常用颜色

void RGB2HSL(in float3 rgb, out float3 hsl) { float precision = 0.00001f; float rgbMax = max(max(rgb.r, rgb.g), rgb.b); float rgbMin = min(min(rgb.r, rgb.g), rgb.b); //hue [flatten] if (abs(rgbMax - rgbMin) < precision) // max == min { hsl.r = 0.0f; } else if (abs(rgbMax - rgb.r) < precision) // max == r { hsl.r = 60.0f * (rgb.g - rgb.b) / (rgbMax - rgbMin); if (rgb.g < rgb.b) hsl.r += 360.0f; } else if (abs(rgbMax - rgb.g) < precision) // max == g { hsl.r = 60.0f * (rgb.b - rgb.r) / (rgbMax - rgbMin) + 120.0f; } else if (abs(rgbMax - rgb.g) < precision) // max == b { hsl.r = 60.0f * (rgb.r - rgb.g) / (rgbMax - rgbMin) + 240.0f; } // light hsl.b = (rgbMax + rgbMin) / 2.0f; // saturation [flatten] if (hsl.b <= precision || abs(rgbMax - rgbMin) < precision) { hsl.g = 0.0f; } else if (hsl.b > 0.0f && hsl.b <= 0.5f) { hsl.g = (rgbMax - rgbMin) / (rgbMax + rgbMin); } else if (hsl.b > 0.5f) { hsl.g = (rgbMax - rgbMin) / (2 - (rgbMax + rgbMin)); } } float ToColor(float p, float q, float t) { [flatten] if (t < 0.0f) t = t + 1.0f; else if (t > 1.0f) t = t - 1.0f; float c = 0.0f; [flatten] if (t < 0.f) { c = p + ((q - p) * 6 * t); } else if (t >= 0.f && t < 0.5f) { c = q; } else if (t >= 0.5f && t < 0.66667f) { c = p + ((q - p) * 6 * (0.66667f - t)); } else { c = p; } return c; } void HSL2RGB(in float3 hsl, out float3 rgb) { float precision = 0.00001f; [flatten] float hue = hsl.r; float sat = hsl.g; float light = hsl.b; if (sat < precision) // sat == 0 { rgb = hsl.bbb; } else { float q = 0.0f, p = 0.0f, hk = 0.0; if (light < 0.5f) { q = light * (1 + sat); } else { q = light + sat - (light * sat); } p = 2.0f * light - q; hk = hue / 360.0f; rgb.r = ToColor(p, q, hk + 0.33333f); rgb.g = ToColor(p, q, hk); rgb.b = ToColor(p, q, hk - 0.33333f); } } 

php版本

colors - PHP HSV to RGB formula comprehension - Stack Overflow

<?php $hue = 209; $sat = 75; $lum = 60; $hue /= 360; $sat /= 100; $lum /= 100; $result = ColorHSLToRGB($hue, $sat, $lum); var_dump($result); echo '<br>'; printf("rgb = %d,%d,%d<br>", $result['r'], $result['g'], $result['b']); function ColorHSLToRGB($h, $s, $l){ $r = $l; $g = $l; $b = $l; $v = ($l <= 0.5) ? ($l * (1.0 + $s)) : ($l + $s - $l * $s); if ($v > 0){ $m; $sv; $sextant; $fract; $vsf; $mid1; $mid2; $m = $l + $l - $v; $sv = ($v - $m ) / $v; $h *= 6.0; $sextant = floor($h); $fract = $h - $sextant; $vsf = $v * $sv * $fract; $mid1 = $m + $vsf; $mid2 = $v - $vsf; switch ($sextant) { case 0: $r = $v; $g = $mid1; $b = $m; break; case 1: $r = $mid2; $g = $v; $b = $m; break; case 2: $r = $m; $g = $v; $b = $mid1; break; case 3: $r = $m; $g = $mid2; $b = $v; break; case 4: $r = $mid1; $g = $m; $b = $v; break; case 5: $r = $v; $g = $m; $b = $mid2; break; } } return array('r' => $r * 255.0, 'g' => $g * 255.0, 'b' => $b * 255.0); } ?>

js版本

/ * convert a HSL colorscheme to either Hexadecimal (default) or RGB. * * We want a method where we can programmatically generate a series of colors * between two values (eg. red to green) which is easy to do with HSL because * you just change the hue. (0 = red, 120 = green). You can use this function * to convert those hsl color values to either the rgb or hexadecimal color scheme. * e.g. You have * hsl(50, 100%, 50%) * To convert, * $hex = convertHSL(50,100,50); // returns #ffd500 * or * $rgb = convertHSL(50,100,50, false); // returns rgb(255, 213, 0) * * see https://coderwall.com/p/dvsxwg/smoothly-transition-from-green-to-red * @param int $h the hue * @param int $s the saturation * @param int $l the luminance * @param bool $toHex whether you want hexadecimal equivalent or rgb equivalent * @return string usable in HTML or CSS */ function convertHSL($h, $s, $l, $toHex=true){ $h /= 360; $s /=100; $l /=100; $r = $l; $g = $l; $b = $l; $v = ($l <= 0.5) ? ($l * (1.0 + $s)) : ($l + $s - $l * $s); if ($v > 0){ $m; $sv; $sextant; $fract; $vsf; $mid1; $mid2; $m = $l + $l - $v; $sv = ($v - $m ) / $v; $h *= 6.0; $sextant = floor($h); $fract = $h - $sextant; $vsf = $v * $sv * $fract; $mid1 = $m + $vsf; $mid2 = $v - $vsf; switch ($sextant) { case 0: $r = $v; $g = $mid1; $b = $m; break; case 1: $r = $mid2; $g = $v; $b = $m; break; case 2: $r = $m; $g = $v; $b = $mid1; break; case 3: $r = $m; $g = $mid2; $b = $v; break; case 4: $r = $mid1; $g = $m; $b = $v; break; case 5: $r = $v; $g = $m; $b = $mid2; break; } } $r = round($r * 255, 0); $g = round($g * 255, 0); $b = round($b * 255, 0); if ($toHex) { $r = ($r < 15)? '0' . dechex($r) : dechex($r); $g = ($g < 15)? '0' . dechex($g) : dechex($g); $b = ($b < 15)? '0' . dechex($b) : dechex($b); return "#$r$g$b"; } else { return "rgb($r, $g, $b)"; }

参考

RGB 和 HSL 的转换和应用-CSDN博客

RGB 与HSL 色彩空间的转换函数-Excel VBA程序开发-ExcelHome技术论坛 -

HSL（色彩模式）_百度百科

显示屏色域、色深、色差等参数 - 知乎

对于摄像师必备的五彩斑斓的光——斯丹德RGB摄影补光灯（还可蹦迪）_相机配件_什么值得买

在线转换工具

RGB到HSL颜色转换 - RGB到色相、饱和度、亮度转换

HSL到RGB颜色转换