Bij elkaar passende kleuren generator

Voorbeeld (een van de vele mogelijkheden):<?php
echo '<pre>';
var_dump(getColors(10, null, 70, 80, 30, 170));
echo '</pre>';
?>De functies:<?php
/**
 * This function calculates the precision of a float or integer. In other words, the number of digits in a number.
 *
 * @param int|float $number
 * @return int
 */
function getPrecision($number) {
	if (!is_numeric($number)) {
		throw new InvalidArgumentException('Argument $number must be a number');
	}
	settype($number, 'string');
	if ($dotPosition = strrpos($number, '.')) {
		$number = substr($number, 0, $dotPosition) . substr($number, $dotPosition + 1);
	}
	$number = ltrim($number, '0');
	if ($exponentPosition = strrpos($number, 'E')) {
		$number = substr($number, 0, $exponentPosition);
	}
	return strlen($number);
}
/**
 * This function creates a range of at each other appropriate colors with as many contrast as possible in RGB format.
 *
 * @uses hsbToRgb()
 * @uses getPrecision()
 * @uses significantRound()
 * @param int $number The number of colors that needs to be created
 * @param int|float|null $hue This parameter can be a int or float between 0 and 360. If you pass null through, the hue is used as a variable factor by calculating the colors.
 * @param int|float|null $saturation This parameter can be a int or float between 0 and 100. If you pass null through, the saturation is used as a variable factor by calculating the colors.
 * @param unknown_type $brightness This parameter can be a int or float between 0 and 100. If you pass null through, the brightness is used as a variable factor by calculating the colors.
 * @param int|float $hueStart This parameter can be a int or float between 0 and 360. It specifies the starting point of the hue. This parameter has only effect when parameter $hue is set to null. It can be bigger then $hueStop.
 * @param int|float $hueStop This parameter can be a int or float between 0 and 360. It specifies the ending point of the hue. This parameter has only effect when parameter $hue is set to null. It can be smaller then $hueStart.
 * @param int|float $saturationStart This parameter can be a int or float between 0 and 100. It specifies the starting point of the saturation. This parameter has only effect when parameter $saturation is set to null. It can be bigger then $saturationStop.
 * @param int|float $saturationStop This parameter can be a int or float between 0 and 100. It specifies the ending point of the saturation. This parameter has only effect when parameter $saturation is set to null. It can be smaller then $saturationStart.
 * @param int|float $brightnessStart This parameter can be a int or float between 0 and 100. It specifies the starting point of the brightness. This parameter has only effect when parameter $brightness is set to null. It can be bigger then $brightnessStop.
 * @param int|float $brightnessStop This parameter can be a int or float between 0 and 100. It specifies the ending point of the brightness. This parameter has only effect when parameter $brightness is set to null. It can be smaller then $brightnessStart.
 * @param boolean $hueReverse When this parameter is set to true, the calculating of the hue value is reversed. This parameter has only effect when parameter $hue is set to null.
 * @param boolean $saturationReverse When this parameter is set to true, the calculating of the saturation value is reversed. This parameter has only effect when parameter $saturation is set to null.
 * @param boolean $brightnessReverse When this parameter is set to true, the calculating of the brightness value is reversed. This parameter has only effect when parameter $brightness is set to null.
 * @return array The return value is a multidimesional array. Each top-level element has a array with elements 'red', 'green' and 'blue', holding integers from 0 to 255.
 */
function getColors(
	$number,
	$hue,
	$saturation,
	$brightness,
	$hueStart = 0,
	$hueStop = 360,
	$saturationStart = 0,
	$saturationStop = 100,
	$brightnessStart = 0,
	$brightnessStop = 100,
	$hueReverse = false,
	$saturationReverse = false,
	$brightnessReverse = false
) {
	$hueStart = significantRound($hueStart, getPrecision($hueStart));
	if ($hueStart < 0 || $hueStart > 360) {
		throw new LengthException('Argument $hueStart is not a number between 0 and 360.');
	}
	$hueStop = significantRound($hueStop, getPrecision($hueStop));
	if ($hueStop < 0 || $hueStop > 360) {
		throw new LengthException('Argument $hueStop is not a number between 0 and 360.');
	}
	$saturationStart = significantRound($saturationStart, getPrecision($saturationStart));
	if ($saturationStart < 0 || $saturationStart > 100) {
		throw new LengthException('Argument $saturaionStart is not a number between 0 and 100.');
	}
	$saturationStop = significantRound($saturationStop, getPrecision($saturationStop));
	if ($saturationStop < 0 || $saturationStop > 100) {
		throw new LengthException('Argument $saturaionStop is not a number between 0 and 100.');
	}
	$brightnessStart = significantRound($brightnessStart, getPrecision($brightnessStart));
	if ($brightnessStart < 0 || $brightnessStart > 100) {
		throw new LengthException('Argument $brightnessStart is not a number between 0 and 100.');
	}
	$brightnessStop = significantRound($brightnessStop, getPrecision($brightnessStop));
	if ($brightnessStop < 0 || $brightnessStop > 100) {
		throw new LengthException('Argument $brightnessStop is not a number between 0 and 100.');
	}
	if (!is_bool($hueReverse)) {
		throw new InvalidArgumentException('Argument $hueReverse is not a boolean.');
	}
	if (!is_bool($saturationReverse)) {
		throw new InvalidArgumentException('Argument $saturationReverse is not a boolean.');
	}
	if (!is_bool($brightnessReverse)) {
		throw new InvalidArgumentException('Argument $brightnessReverse is not a boolean.');
	}
	$hueRange = max($hueStart, $hueStop) == $hueStop ? $hueStop - $hueStart : 360 - $hueStart + $hueStop;
	$saturationRange = max($saturationStart, $saturationStop) == $saturationStop ? $saturationStop - $saturationStart : 100 - $saturationStart + $saturationStop;
	$brightnessRange = max($brightnessStart, $brightnessStop) == $brightnessStop ? $brightnessStop - $brightnessStart : 100 - $brightnessStart + $brightnessStop;
	$currentHue = $hue;
	$currentSaturation = $saturation;
	$currentBrightness = $brightness;
	$hueBetween = 0;
	$saturationBetween = 0;
	$brightnessBetween = 0;
	if (is_null($hue)) {
		$hueBetween = $hueRange / $number;
		$currentHue = $hueReverse ? $hueStop : $hueStart;
	}
	if (is_null($saturation)) {
		$saturationBetween = $saturationRange / ($number - 1);
		$currentSaturation = $saturationReverse ? $saturationStop : $saturationStart;
	}
	if (is_null($brightness)) {
		$brightnessBetween = $brightnessRange / ($number - 1);
		$currentBrightness = $brightnessReverse ? $brightnessStop : $brightnessStart;
	}
	$colors = array();
	for ($i = 0; $i < $number; $i++) {
		$colors[] = hsbToRgb($currentHue, $currentSaturation, $currentBrightness);
		$currentHue += $hueReverse ? -$hueBetween : $hueBetween;
		$currentSaturation += $saturationReverse ? -$saturationBetween : $saturationBetween;
		$currentBrightness += $brightnessReverse ? -$brightnessBetween : $brightnessBetween;
		$currentHue = significantRound($currentHue, 3) > 360 ? 0 : $currentHue;
		$currentSaturation = significantRound($currentSaturation, 3) > 100 ? 0 : $currentSaturation;
		$currentBrightness = significantRound($currentBrightness, 3) > 100 ? 0 : $currentBrightness;
		$currentHue = significantRound($currentHue, 3) < 0 ? 360 : $currentHue;
		$currentSaturation = significantRound($currentSaturation, 3) < 0 ? 100 : $currentSaturation;
		$currentBrightness = significantRound($currentBrightness, 3) < 0 ? 100 : $currentBrightness;
	}
	return $colors;
}
?>