php - hexadecimal - rgba to hex

Porcentaje de Hexcolor en PHP

Question

Me gustaría hacer un porcentaje en un color hexadecimal. Como funcionan los grados de color HSV ...
Estoy usando PHP.

IE:
0% : RED (#FF0000)
8% : ORANGE (#FF7F00)
17% : YELLOW (#FFFF00)
25% : LIMEGREEN (#7FFF00)
... : ...
83% : MAGENTA (#FF00FF)
92% : ROSE (#FF007F)
100% : RED (#FF0000)

Answer 1

Este no es mi código y no recuerdo dónde lo encontré. Lo he usado durante un par de años y funciona perfectamente para mí. Podría ser lo que estás buscando (o parte de él puede ser).

<?php
class colour
{
protected $R = 0; //Red
protected $G = 0; //Green
protected $B = 0; //Blue
protected $H = 0; //Hue
protected $S = 0; //Saturation
protected $L = 0; //Luminance
protected $hex = 0;
protected $web;
protected $complement;
public function __construct($r, $g = false, $b = false)
{
//set up array of web colour names
$this->web = array(
''black'' => ''#000000'',
''green'' => ''#008000'',
''silver'' => ''#C0C0C0'',
''lime'' => ''#00FF00'',
''gray'' => ''#808080'',
''olive'' => ''#808000'',
''white'' => ''#FFFFFF'',
''yellow'' => ''#FFFF00'',
''maroon'' => ''#800000'',
''navy'' => ''#000080'',
''red'' => ''#FF0000'',
''blue'' => ''#0000FF'',
''purple'' => ''#800080'',
''teal'' => ''#008080'',
''fuchsia'' => ''#FF00FF''
);
//accept either R,G,B or hex colour
//If hex, convert to RGB
//RGB?
if($r && $g && $b){
//yes then save
$this->R = $r;
$this->G = $g;
$this->B = $b;
} elseif(isset($this->web[strtolower($r)])){
//named colour?
$this->hex = $this->web[strtolower($r)];
$this->convertToRGB($this->hex);
} else {
//no - so convert
if($r[0] != ''#'') $r = ''#'' . $r;
$this->hex = $r;
$this->convertToRGB($r);
}
$this->rgbTohsl();
//$this->complement = $this->getComplement();
}
public function getLighter($factor)
{
//return colour lightened by %$factor in hex
//$factor can be negative to give a darker colour
if($factor > 1 || $factor < -1) $factor = $factor/100;
$r = (string)round($this->R+((255 - $this->R) * $factor));
$g = (string)round($this->G+((255 - $this->G) * $factor));
$b = (string)round($this->B+((255 - $this->B) * $factor));
if($r > 255)$r = 255;
if($r < 0)$r = 0;
if($g > 255)$g = 255;
if($g < 0)$g = 0;
if($b > 255)$b = 255;
if($b < 0)$b = 0;
var_dump($r, $g, $b);
return $this->convertToHex($r, $g, $b);
}
public function opposite()
{
$r = $this->R;
$g = $this->G;
$b = $this->B;
$r = 255 - $r;
$g = 255 - $g;
$b = 255 - $b;
return $this->convertToHex($r, $g, $b);
}
public function getRGB()
{
//returns an array (r, g, b)
$rgb = array( ''r'' => $this->R,
''g'' => $this->G,
''b'' => $this->B);
return $rgb;
}
public function getHex()
{
if($this->hex) return $this->hex;
$hex = ''#'' . dechex($this->R) . dechex($this->G) . dechex($this->B);
return $hex;
}
public static function namedToHex($name)
{
//return hex value of named colour
$web = array(
''black'' => ''#000000'',
''green'' => ''#008000'',
''silver'' => ''#C0C0C0'',
''lime'' => ''#00FF00'',
''gray'' => ''#808080'',
''olive'' => ''#808000'',
''white'' => ''#FFFFFF'',
''yellow'' => ''#FFFF00'',
''maroon'' => ''#800000'',
''navy'' => ''#000080'',
''red'' => ''#FF0000'',
''blue'' => ''#0000FF'',
''purple'' => ''#800080'',
''teal'' => ''#008080'',
''fuchsia'' => ''#FF00FF''
);
if(isset($web[strtolower($name)])){
return $web[strtolower($name)];
}
return false;
}
public static function contrast(colour $fg, colour $bg){
//calculate and return contrast between $fg and $bg
$cont = 1;
$fglum = $fg->luminance();
$bglum = $bg->luminance();
if($fglum > $bglum) $cont = ($fglum + 0.05) / ($bglum + 0.05);
if($bglum > $fglum) $cont = ($bglum + 0.05) / ($fglum + 0.05);
return $cont;
}
public static function colourDiff(colour $colour1, colour $colour2)
{
//returns the colour difference between two colours
$rgb1 = $colour1->getRGB();
$rgb2 = $colour2->getRGB();
$r1 = $rgb1[''r''];
$r2 = $rgb2[''r''];
$g1 = $rgb1[''g''];
$g2 = $rgb2[''g''];
$b1 = $rgb1[''b''];
$b2 = $rgb2[''b''];
$diff = max($r1, $r2) - min($r1, $r2);
$diff += max($g1, $g2) - min($g1, $g2);
$diff += max($b1, $b2) - min($b1, $b2);
return $diff;
}
public function brightness()
{
return (($this->R * 299) + ($this->G * 587) + ($this->B * 114))/1000;
}
public function luminance()
{
//returns luminence of coulour
$r = $this->lumCheck($this->R/255);
$g = $this->lumCheck($this->G/255);
$b = $this->lumCheck($this->B/255);
$lum = (0.2126 * $r) + (0.7152 * $g) + (0.0722 * $b);
return $lum;
}
protected function lumCheck($col)
{
if($col <= 0.03298){
return $col/12.92;
} else {
return pow((($col + 0.055)/1.055), 2.4);
}
}
protected function convertToRGB($color)
{
$color = (string)$color;
if($color[0] == ''#''){
$color = substr($color, 1);
}
if(strlen($color) == 6){
list($r, $g, $b) = array($color[0].$color[1],
$color[2].$color[3],
$color[4].$color[5]);
}
elseif(strlen($color) == 3){
list($r, $g, $b) = array($color[0].$color[0], $color[1].$color[1], $color[2].$color[2]);
}
else{
return false;
}
$r = hexdec($r); $g = hexdec($g); $b = hexdec($b);
$this->R = (int)$r;
$this->G = (int)$g;
$this->B = (int)$b;
}
protected function convertToHex($r, $g, $b)
{
$r = dechex($r);
if(strlen($r) == 1)$r = ''0'' . $r;
$g = dechex($g);
if(strlen($g) == 1)$g = ''0'' . $g;
$b = dechex($b);
if(strlen($b) == 1)$b = ''0'' . $b;
$hex = ''#'' . $r . $g . $b;
return $hex;
}
protected function rgbTohsl()
{
$r = ( $this->R / 255 ); //RGB from 0 to 255
$g = ( $this->G / 255 );
$b = ( $this->B / 255 );
$var_Min = min( $r, $g, $b ); //Min. value of RGB
$var_Max = max( $r, $g, $b ); //Max. value of RGB
$del_Max = $var_Max - $var_Min; //Delta RGB value
$l = ( $var_Max + $var_Min ) / 2;
$this->L = $l;
if ( $del_Max == 0 ){ //This is a gray, no chroma...
$this->H = 0; //HSL results from 0 to 1
$this->S = 0;
} else { //Chromatic data...
if ( $l < 0.5 ) {
$this->S = $del_Max / ( $var_Max + $var_Min );
} else {
$this->S = $del_Max / ( 2 - $var_Max - $var_Min );
$del_R = ( ( ( $var_Max - $r ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;
$del_G = ( ( ( $var_Max - $g ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;
$del_B = ( ( ( $var_Max - $b ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;
if( $r == $var_Max ){
$h = $del_B - $del_G;
} elseif( $g == $var_Max ){
$h = ( 1 / 3 ) + $del_R - $del_B;
} elseif( $b == $var_Max ) {
$h = ( 2 / 3 ) + $del_G - $del_R;
}
if ( $h < 0 ) $h += 1;
if ( $h > 1 ) $h -= 1;
$this->H = $h;
}
}
}
protected function hslTorgb($h, $s, $l)
{
if ( $s == 0 ){ //HSL from 0 to 1
$r = $l * 255; //RGB results from 0 to 255
$g = $l * 255;
$b = $l * 255;
} else {
if ( $l < 0.5 ) {
$var_2 = $l * ( 1 + $s );
} else {
$var_2 = ( $l + $s ) - ( $s * $l );
}
$var_1 = 2 * $l - $var_2;
$r = 255 * $this->hueToRGB( $var_1, $var_2, $h + ( 1 / 3 ) );
$g = 255 * $this->hueToRGB( $var_1, $var_2, $h );
$b = 255 * $this->hueToRGB( $var_1, $var_2, $h - ( 1 / 3 ) );
}
return array(''r''=>$r,''g''=>$g,''b''=>$b);
}
protected function hueToRGB($v1, $v2, $vH)
{
if($vH < 0)$vH += 1;
if($vH > 1)$vH -= 1;
if ( ( 6 * $vH ) < 1 ) return ( $v1 + ( $v2 - $v1 ) * 6 * $vH );
if ( ( 2 * $vH ) < 1 ) return ( $v2 );
if ( ( 3 * $vH ) < 2 ) return ( $v1 + ( $v2 - $v1 ) * ( ( 2 / 3 ) - $vH ) * 6 );
return ( $v1 );
}
public function getComplement()
{
$h = $this->H + 180;
if($h > 360)$h -= 360;
$rgb = $this->hslTorgb($h, $this->S, $this->L);
return $this->convertToHex($rgb[''r''], $rgb[''g''], $rgb[''b'']);
}
}

Answer 2

Este pequeño fragmento parece hacer lo que intentas lograr

http://bytes.com/topic/php/insights/890539-how-produce-first-pair-rgb-hex-color-value-percent-value

function percent2Color($value,$brightness = 255, $max = 100,$min = 0, $thirdColorHex = ''00'')
{
// Calculate first and second color (Inverse relationship)
$first = (1-($value/$max))*$brightness;
$second = ($value/$max)*$brightness;
// Find the influence of the middle color (yellow if 1st and 2nd are red and green)
$diff = abs($first-$second);
$influence = ($brightness-$diff)/2;
$first = intval($first + $influence);
$second = intval($second + $influence);
// Convert to HEX, format and return
$firstHex = str_pad(dechex($first),2,0,STR_PAD_LEFT);
$secondHex = str_pad(dechex($second),2,0,STR_PAD_LEFT);
return $firstHex . $secondHex . $thirdColorHex ;
// alternatives:
// return $thirdColorHex . $firstHex . $secondHex;
// return $firstHex . $thirdColorHex . $secondHex;
}

Answer 3

Intente convertir el porcentaje a HSV (divida el porcentaje entre 100 para obtener el matiz y simplemente establezca la saturación y el valor en una constante arbitraria como 1) y luego use esta pregunta para convertirla a formato RGB: comprensión de la fórmula PHP HSV a RGB