colors - 确定 HSL 变化以将颜色转换为另一种颜色

Question

我使用 LESS ，我想利用各种集成的 color functions 只允许设置几个基本颜色，然后派生其他改变色相，饱和度，亮度，旋转，ecc。

假设我们的着色器中有以下 2 种颜色(在本例中为浅绿色和深绿色):

@primary-color:    rgb(0,100,60);
@secondary-color:  rgb(185,215,50); 

我想仅显式设置 @primary-color，然后在适当的 HSL 转换后获取 @secondary-color。 (例如 darken(hsl(90, 80%, 50%), 20% ))

有什么方法可以确定 我必须对 @primary-color 应用什么 hsl 设置才能获得 @secondary-color 吗？

换句话说:

给定 2 个 RGB 颜色定义，是否有任何方法可以确定它们之间在色调、饱和度和亮度方面存在哪些差异，以将 @secondary-color 表示为 @primary-color 的变体？

P.S.:如有必要，也可以借助 Photoshop 等外部工具。

Answer 1

这里是计算两种颜色的色调、饱和度和亮度值之间的差异，然后用它来计算基于第一种颜色的第二种颜色的方法。

各个步骤如下:

色差计算: 使用 hue() 、 saturation() 和 lightness() 函数计算两种给定颜色之间的色相、饱和度和亮度差异。此功能可以单独使用，只是为了单独输出差异。

到达基于原色的二次色: 这是一个三步过程，它们如下:

使用 spin() 函数通过传递两种颜色之间的色调差异来调整原色的色调

根据差异使用 saturate() 或 desaturate() 函数调整色相调整后的颜色(来自上一步)的饱和度。

根据差异使用 darken() 或 lighten() 函数调整饱和度调整后的颜色(来自上一步)的亮度。

这个答案是这个 SASS Article 关于如何从另一种颜色计算一种颜色的较少改编。

@primary: rgb(0,100,60); /* primary color */
@secondary: rgb(185,215,50); /* secondary color */

/* mixin to calculate the difference between two given colors */
.color-diff(@color1; @color2){ 
    @hueDiff: hue(@color2) - hue(@color1);
    @saturationDiff: saturation(@color1) - saturation(@color2);
    @lightnessDiff: lightness(@color1)- lightness(@color2);

    color1: @color1; color2:@color2; /* just for testing, can be removed */
}

/* Step 1: mixin to adjust the hue difference between the colors */
.adjust-hue(@color; @diff){ 
    @hueAdjusted: spin(@color, @hueDiff);
}

/* Step 2: mixin to adjust the saturation difference */
.adjust-saturation(@color; @diff) when (@diff > 0){
    @satAdjusted: desaturate(@color, abs(@diff)); /* desaturate if diff is greater than 0 */
}
.adjust-saturation(@color; @diff) when not (@diff > 0){
    @satAdjusted: saturate(@color, abs(@diff)); /* saturate if diff is not greater than 0 */
}

/* Step 3: mixin to adjust the lightness diff between the colors */
.adjust-lightness(@color; @diff) when (@diff > 0){
    @lightnessAdjusted: darken(@color, abs(@diff)); /* darken if diff is greater than 0 */
}
.adjust-lightness(@color; @diff) when not (@diff > 0){
    @lightnessAdjusted: lighten(@color, abs(@diff)); /* else lighten */
}

div{
    .color-diff(@primary; @secondary);
    .adjust-hue(@primary; @hueDiff);
    .adjust-saturation(@hueAdjusted; @saturationDiff);
    .adjust-lightness(@satAdjusted; @lightnessDiff);
    color: @lightnessAdjusted; /* final output value */
}

编译的 CSS:

div {
    color1: #00643c;
    color2: #b9d732;
    color: #b9d732;
}

如果您只想获得两种颜色之间的差异，那么您可以使用如下所示的循环来输出色调、饱和度和亮度值方面的差异。

@color-list-1: rgb(0,100,60), #B0BCA7, #ABCDEF; /* list of primary colors */
@color-list-2: rgb(185,215,50), #BADA55, #FEDCBA; /* list of secondary colors */

#output{
    .loop-colors(@index) when (@index > 0){
        @primary: extract(@color-list-1, @index);
        @secondary: extract(@color-list-2, @index);
        .color-diff(@primary; @secondary);

        /* output the values of the comparison */
        color-comparison-@{index}+: ~"Hue Difference: @{hueDiff}";
        color-comparison-@{index}+: ~"Saturation Difference: @{saturationDiff}";        
        color-comparison-@{index}+: ~"Lightness Difference: @{lightnessDiff}";
        .loop-colors(@index - 1);
    }
    .loop-colors(length(@color-list-1));
}

上面的代码将比较两个列表中的相应值并输出它们的差异，如下所示:

#output {
  color-comparison-3: Hue Difference: -180, Saturation Difference: -29.142857142857153%, Lightness Difference: -5.882352941176478%;
  color-comparison-2: Hue Difference: -19.849624060150404, Saturation Difference: -50.70282063269439%, Lightness Difference: 10.196078431372548%;
  color-comparison-1: Hue Difference: -85.09090909090908, Saturation Difference: 32.65306122448979%, Lightness Difference: -32.352941176470594%;
}