Question

我必须绘制一些shart（Highcharts，php）。大约有20列。我需要它们是不同的颜色，但颜色应该是某种颜色的阴影（比如绿色）。我根据列上的某些值创建颜色，如：

function stringToColorCode($string) {
    $code = dechex(crc32($string));
    $code = substr($code, 0, 6);
    return '#' . $code;
}

我是如何得到这种颜色的。我该怎么办才能使所有颜色看起来像绿色？感谢。

Answer 1

使用此功能，您可以以十六进制格式创建深色或浅色的颜色：

/**
 * string  $code Color in hex format, e.g. '#ff0000'
 * int     $percentage A number between 0 and 1, e.g. 0.3
 *         1 is the maximum amount for the shade, and thus means black 
 *         or white depending on the parameter $darken.
 *         0 returns the color in $code itself.
 * boolean $darken True if the function should return a dark shade of $code
 *         or false if the function should return a light shade of $code. 
 */
function colorCodeShade($code, $percentage, $darken=true) {

    // split color code in its rgb parts and convert these into decimal numbers
    $r = hexdec(substr($code, 1, 2));
    $g = hexdec(substr($code, 3, 2));
    $b = hexdec(substr($code, 5, 2));

    if($darken) {
        $newR = dechex($r * (1 - $percentage));
        $newG = dechex($g * (1 - $percentage));
        $newB = dechex($b * (1 - $percentage));
    } else {
        $newR = dechex($r + (255 - $r) * $percentage);
        $newG = dechex($g + (255 - $g) * $percentage);
        $newB = dechex($b + (255 - $b) * $percentage);
    }

    if(strlen($newR) == 1) $newR = '0'.$newR;
    if(strlen($newG) == 1) $newG = '0'.$newG;
    if(strlen($newB) == 1) $newB = '0'.$newB;

    return '#'.$newR.$newG.$newB;

}

echo '<span style="color:'.colorCodeShade('#204a96', 0.5, true).'">test</span>';
echo '<span style="color:'.colorCodeShade('#204a96', 0.5, false).'">test</span>';

获得一些颜色的调色板

1 个答案: