Colors

Anywhere a color goes, it can be given as a CSS color string, a color object or an array.

Qr::url($url)->paint('#1e1b4b');
Qr::url($url)->paint('rebeccapurple');
Qr::url($url)->paint('oklch(45% 0.2 293)');
Qr::url($url)->paint(['r' => 30, 'g' => 27, 'b' => 75]);
Qr::url($url)->paint(Oklch::make(0.45, 0.2, 293));

Color spaces

Class	CSS
Hex	#rgb, #rgba, #rrggbb, #rrggbbaa
Rgb, Rgba	rgb(190 18 60), rgb(190 18 60 / 0.5), rgba(190, 18, 60, 0.5)
Hsl, Hsla	hsl(345 83% 41%), hsla(345, 83%, 41%, 0.5)
Hwb	hwb(345 7% 25%)
Lab, Lch	lab(54.29% 80.8 69.89), lch(54.29% 106.84 40.85)	CIE
Oklab, Oklch	oklab(62.8% 0.225 0.126), oklch(62.8% 0.258 29.23)	perceptual: equal steps look equal
Cmyk	cmyk(0% 91% 68% 25%)	naive device CMYK
Named	red, rebeccapurple, transparent, currentColor	the CSS names, and your own

All of them live in ExeQue\Qr\Colors and implement ExeQue\Qr\Contracts\Color:

use ExeQue\Qr\Colors\Color;
use ExeQue\Qr\Colors\Hex;
use ExeQue\Qr\Colors\Oklch;

$color = Color::parse('hsl(345 83% 41%)');   // whichever class the notation is
$color = Color::make($anyForm);              // a string, an array or a color

Oklch::from($color);   // the same color in another space
$color->toRgba();      // sRGB, brought into gamut
$color->toHex();       // #be123c
$color->toCss();       // in its own notation
$color->alpha();
$color->withAlpha(0.5);

Colors outside sRGB, such as vivid oklch() colors, are brought into gamut the way CSS does it, keeping their lightness and hue.

Adjusting colors

$brand = Hex::make('#be123c');

$brand->lighten(20);   // 20 points lighter, in perceived lightness (OKLCH), up to white
$brand->darken(20);    // 20 points darker, down to black
$brand->shift(180);    // the hue turned 180 degrees round the OKLCH color wheel
$brand->invert();      // the opposite color in sRGB

Each returns a color of the same class where that class can hold it. Lightening and darkening work in OKLCH, so twenty points look like the same step for every hue. The mixed-shade filter uses them to give each module its own shade.

Names of your own

Define names once, in config/qr.php:

'colors' => [
    'brand' => '#be123c',
    'ink' => 'oklch(25% 0.05 270)',
    'overlay' => 'rgb(0 0 0 / 50%)',
],

or in a service provider:

Qr::colors()->register('brand', '#be123c');

Qr::colors() also tells what is there: names(), has('brand'), get('brand') and all().

and use them like CSS names, anywhere: ->paint('brand'). A name keeps its color's alpha. In SVG output a name of your own is written as the color itself, since only your application knows it.

currentColor

currentColor takes the color of the text around the code, so CSS colors it. It only means something in inline SVG:

Qr::url($url)->svg(currentColor: true);     // the code's own paint written as currentColor
Qr::url($url)->paint('currentColor')->svg();

<x-qr :content="$url" current-color class="text-indigo-900 dark:text-indigo-100" />

Contrast

use ExeQue\Qr\Colors\Contrast;

Contrast::ratio(Hex::make('#be123c'), Hex::make('#ffffff'));   // 6.3, the WCAG ratio

The scan guards check every drawn color against the background with this, opacity included.