MMO\core\colors

MMO\core\colors · 5 symbols · generated 30 Sep 2026

function

gradientOf

Interpolates a color along a linear gradient between two colors, based on a normalized position (0 to 1).

function gradientOf(float $value, string $startColor, string $endColor): string

Namespace: MMO\core\colors

Interpolation happens per RGB channel; $value is clamped so callers don't need to pre-clamp it themselves.

$value	float	A value between 0 (start color) and 1 (end color). Values outside [0,1] are clamped.
$startColor	string	Hex color code (e.g., "#DC143C"), or anything accepted by `hexToRgb`
$endColor	string	Hex color code (e.g., "#32CD32"), or anything accepted by `hexToRgb`
returns	string	The interpolated color as hex (e.g., "#ABC123")

gradientOf(0, '#ff0000', '#00ff00'); // "#ff0000" (start color) gradientOf(1, '#ff0000', '#00ff00'); // "#00ff00" (end color) gradientOf(0.5, '#ff0000', '#00ff00'); // "#808000" (halfway point) //typical use: color a progress/heat indicator from red (0%) to green (100%) gradientOf($percentDone / 100, 'red', 'green');

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Uses (2)

function

hexToRgb

colors.php:172

Converts a hex color (6-digit, or the 3-digit CSS shorthand) or a named HTML color to an RGB array.

function hexToRgb(string $hex): array

Namespace: MMO\core\colors

NOTE: the 8-digit `#RRGGBBAA` form is read but its alpha byte is silently ignored (only 'transparent' in HTML_COLORS uses it, and it happens to be all zeroes, so this has never surfaced as an issue in practice).

$hex	string	Hex color with or without '#' (6-digit or 3-digit shorthand), or a name from HTML_COLORS
returns	array	Array with keys 'r', 'g', 'b' containing values 0-255

hexToRgb('#DC143C'); // ['r' => 220, 'g' => 20, 'b' => 60] hexToRgb('DC143C'); // same, the leading '#' is optional hexToRgb('#fff'); // ['r' => 255, 'g' => 255, 'b' => 255] -- 3-digit shorthand is expanded first hexToRgb('crimson'); // ['r' => 220, 'g' => 20, 'b' => 60] -- resolved through HTML_COLORS

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Used by (2)

function

luminance

colors.php:252

Compute the WCAG 2.0 relative luminance of a color (0 = darkest black, 1 = brightest white).

function luminance(string $color): float

Namespace: MMO\core\colors
See: https://www.w3.org/TR/WCAG20/#relativeluminancedef

This is the perceptual-brightness formula behind WCAG contrast-ratio calculations: it first linearizes each sRGB channel (undoing the gamma curve monitors apply) before weighting them by the eye's sensitivity to each channel (green contributes the most, blue the least) -- a plain average of R/G/B would not match how bright a color actually looks.

$color	string	Hex color code, or anything accepted by `hexToRgb`
returns	float	the relative luminance, between 0 and 1

luminance('#ffffff'); // 1.0 (white) luminance('#000000'); // 0.0 (black) luminance('#ffff00'); // ~0.9278 (yellow reads as very bright)

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Uses (1)

hexToRgb

Used by (1)

textColor

function

rgbToHex

colors.php:200

Converts RGB values to a hex color. Out-of-range channels are clamped to 0-255: without this, a negative value fed to dechex() would produce a huge two's-complement hex string (e.g. dechex(-1) is 16 'f's) and silently corrupt the result instead of producing a valid color.

function rgbToHex(int $r, int $g, int $b): string

Namespace: MMO\core\colors

$r	int	Red (clamped to 0-255)
$g	int	Green (clamped to 0-255)
$b	int	Blue (clamped to 0-255)
returns	string	Hex color with '#' (e.g., "#DC143C")

rgbToHex(220, 20, 60); // "#dc143c" rgbToHex(-10, 300, 60); // "#00ff3c" -- out-of-range channels are clamped rather than corrupting the output

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Used by (1)

gradientOf

function

textColor

colors.php:278

Pick whichever of 'black'/'white' text reads better on top of the given background color.

function textColor(string $color): string

Namespace: MMO\core\colors

0.179 is the WCAG relative-luminance crossover point at which black and white text reach equal contrast against the background (derived from the WCAG contrast-ratio formula `(L1+0.05)/(L2+0.05)`); above it, black text has the better contrast, at or below it, white does.

$color	string	the background's hex color, or anything accepted by `hexToRgb`
returns	string	'black' or 'white'

textColor('#ffffff'); // 'black' (black text on a white background) textColor('#000000'); // 'white' (white text on a black background) textColor('#ffcc00'); // 'black' (amber is bright enough for black text)

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Uses (1)

luminance