I wanted to use Soma's Sliders to generate hsl colours.( 3 sliders ) But Older IE needs rgb.
here's just a bunch of code I used/created to manage it.
maybe helpful.
<?php header("Content-type: text/css");
// rgbToHsl
function rgbToHsl ( array $rgb ) {
list( $r, $g, $b ) = $rgb;
$r/= 255;
$g/= 255;
$b/= 255;
$max = max( $r, $g, $b );
$min = min( $r, $g, $b );
$h;
$s;
$l = ( $max + $min )/ 2;
if ( $max == $min ) {
$h = $s = 0;
} else {
$d = $max - $min;
$s = $l > 0.5 ? $d/ ( 2 - $max - $min ) : $d/ ( $max + $min );
switch( $max ) {
case $r:
$h = ( $g - $b )/ $d + ( $g < $b ? 6 : 0 );
break;
case $g:
$h = ( $b - $r )/ $d + 2;
break;
case $b:
$h = ( $r - $g )/ $d + 4;
break;
}
$h/= 6;
}
return array( $h, $s, $l );
}
// hslToRgb
function hslToRgb ( array $hsl ) {
list( $h, $s, $l ) = $hsl;
$r;
$g;
$b;
if ( $s == 0 ) {
$r = $g = $b = $l;
}
else {
$q = $l < 0.5 ? $l * ( 1 + $s ) : $l + $s - $l * $s;
$p = 2 * $l - $q;
$r = hueToRgb( $p, $q, $h + 1/ 3 );
$g = hueToRgb( $p, $q, $h );
$b = hueToRgb( $p, $q, $h - 1/ 3 );
}
return array( round( $r * 255 ), round( $g * 255 ), round( $b * 255 ) );
}
// Convert percentages to points (0-255)
function normalizeCssRgb ( array $rgb ) {
foreach ( $rgb as &$val ) {
if ( strpos( $val, '%' ) !== false ) {
$val = str_replace( '%', '', $val );
$val = round( $val * 2.55 );
}
}
return $rgb;
}
// cssHslToRgb
function cssHslToRgb ( array $hsl ) {
// Normalize the hue degree value then convert to float
$h = array_shift( $hsl );
$h = $h % 360;
if ( $h < 0 ) {
$h = 360 + $h;
}
$h = $h/ 360;
// Convert s and l to floats
foreach ( $hsl as &$val ) {
$val = str_replace( '%', '', $val );
$val/= 100;
}
list( $s, $l ) = $hsl;
$hsl = array( $h, $s, $l );
$rgb = hslToRgb( $hsl );
return $rgb;
}
// hueToRgb
function hueToRgb ( $p, $q, $t ) {
if ( $t < 0 ) $t += 1;
if ( $t > 1 ) $t -= 1;
if ( $t < 1/6 ) return $p + ( $q - $p ) * 6 * $t;
if ( $t < 1/2 ) return $q;
if ( $t < 2/3 ) return $p + ( $q - $p ) * ( 2/ 3 - $t ) * 6;
return $p;
}
// rgbToHex
function rgbToHex ( array $rgb ) {
$hex_out = '#';
foreach ( $rgb as $val ) {
$hex_out .= str_pad( dechex( $val ), 2, '0', STR_PAD_LEFT );
}
return $hex_out;
}
// hexToRgb
function hexToRgb ( $hex ) {
$hex = substr( $hex, 1 );
// Handle shortened format
if ( strlen( $hex ) === 3 ) {
$long_hex = array();
foreach ( str_split( $hex ) as $val ) {
$long_hex[] = $val . $val;
}
$hex = $long_hex;
}
else {
$hex = str_split( $hex, 2 );
}
return array_map( 'hexdec', $hex );
}
/**
*
* Output to a "r, g, b" string
*
*/
function colorStringRGB($h, $s, $l ) {
$output = '';
$hsl = array($h, $s, $l);
$color = cssHslToRgb($hsl);
foreach( $color as $rgb ) $output .= $rgb . ', ';
$output = rtrim( $output, ', ' );
return $output;
}
// ---------------------------------------------------------------------------------------
$out = '';
$sections = array(
'aa' => 'value-a',
'bb' => 'value-b',
'cc' => 'value-c',
'dd' => 'value-d',
'ee' => 'value-e',
'ff' => 'value-f',
'gg' => 'value-g',
);
/**
*
* Converts HSL to RGB.
*
*
*/
$minH = $page->css_hue->min;
$maxH = $page->css_hue->max;
$count = count($sections);
$steps = round(( $maxH - $minH ) / $count);
$minL = $page->css_lightness->min;
$maxL = $page->css_lightness->max;
// l is defined in the foreach
$h = $page->css_check == 1 ? $minH : $maxH;
$s = $page->css_saturation;
foreach($sections as $key => $value) {
$out .= "\n\nli." . $key . ' {';
$out .= "\n\t" . 'background-color: rgb(' . colorStringRGB($h, ($s+20), $minL) . ');';
$out .= "\n" . '}';
$out .= "\n";
$out .= "\n\ndiv." . $key . ' {';
$out .= "\n\t" . 'background-color: rgb(' . colorStringRGB($h, ($s+20), $minL) . ');';
$out .= "\n" . '}';
$out .= "\n";
$out .= "\n." . $key . ' .column { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(2n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(3n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(5n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(7n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(11n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(13n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(17n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column:nth-child(23n) { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column.r1.c8 { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$out .= "\n." . $key . ' .column.r3.c1 { background-color: rgb(' . colorStringRGB($h, $s, rand($minL,$maxL)) . '); }';
$h = $page->css_check == 1 ? $h + $steps : $h - $steps;
}
echo $out;
?>
